Pentoxifylline reduces inflammation and prevents myocardial perfusion derangements in experimental chronic Chagas' cardiomyopathy.

BACKGROUND: Myocardial perfusion defect (MPD) is common in chronic Chagas cardiomyopathy (CCC) and is associated with inflammation and development of left ventricular systolic dysfunction. We tested the hypothesis that pentoxifylline (PTX) could reduce inflammation and prevent the development of MPD in a model of CCC in hamsters. METHODS AND RESULTS: We investigated with echocardiogram and rest myocardial perfusion scintigraphy at baseline (6-months after T. cruzi infection/saline) and post-treatment (after additional 2-months of PTX/saline administration), female Syrian hamsters assigned to 3 groups: T. cruzi-infected animals treated with PTX (CH + PTX) or saline (CH + SLN); and uninfected control animals (CO). At the baseline, all groups showed similar left ventricular ejection fraction (LVEF) and MPD areas. At post-treatment evaluation, there was a significant increase of MPD in CH + SLN group (0.8 ± 1.6 to 9.4 ± 9.7%), but not in CH + PTX (1.9 ± 3.0% to 2.7 ± 2.7%) that exhibited MPD area similar to CO (0.0 ± 0.0% to 0.0 ± 0.0%). The LVEF decreased in both infected groups. Histological analysis showed a reduced inflammatory infiltrate in CH + PTX group (395.7 ± 88.3 cell/mm2), as compared to CH + SLN (515.1 ± 133.0 cell/mm2), but larger than CO (193.0 ± 25.7 cell/mm2). The fibrosis and TNF-α expression was higher in both infected groups. CONCLUSIONS: The prolonged use of PTX is associated with positive effects, including prevention of MPD development and reduction of inflammation in the chronic hamster model of CCC.

Association of left ventricular abnormalities with incident cerebrovascular events and sources of thromboembolism in patients with chronic Chagas cardiomyopathy.

BACKGROUND: Although Chagas cardiomyopathy is related to thromboembolic stroke, data on risk factors for cerebrovascular events in Chagas disease is limited. Thus, we assessed the relationship between left ventricular (LV) impairment and cerebrovascular events and sources of thromboembolism in patients with Chagas cardiomyopathy. METHODS: This retrospective cohort included patients with chronic Chagas cardiomyopathy who underwent cardiovascular magnetic resonance (CMR). CMR was performed with a 1.5 T scanner to provide LV volumes, mass, ejection fraction (LVEF), and myocardial fibrosis. The primary outcome was a composite of incident ischemic cerebrovascular events (stroke or transient ischemic attack-TIA) and potential thromboembolic sources (atrial fibrillation (AF), atrial flutter, or intracavitary thrombus) during the follow-up. RESULTS: A total of 113 patients were included. Median age was 56 years (IQR: 45-67), and 58 (51%) were women. The median LVEF was 53% (IQR: 41-62). LV aneurysms and LV fibrosis were present in 38 (34%) and 76 (67%) individuals, respectively. The median follow-up time was 6.9 years, with 29 events: 11 cerebrovascular events, 16 had AF or atrial flutter, and two had LV apical thrombosis. In the multivariable model, only lower LVEF remained significantly associated with the outcomes (HR: 0.96, 95% CI: 0.93-0.99). Patients with reduced LVEF lower than 40% had a much higher risk of cerebrovascular events and thromboembolic sources (HR: 3.16 95% CI: 1.38-7.25) than those with normal LVEF. The combined incidence rate of the combined events in chronic Chagas cardiomyopathy patients with reduced LVEF was 13.9 new cases per 100 persons-year. CONCLUSIONS: LV systolic dysfunction is an independent predictor of adverse cerebrovascular events and potential sources of thromboembolism in patients with chronic Chagas cardiomyopathy.

Heart rate variability as a biomarker in patients with Chronic Chagas Cardiomyopathy with or without concomitant digestive involvement and its relationship with the Rassi score.

BACKGROUND: Dysautonomia plays an ancillary role in the pathogenesis of Chronic Chagas Cardiomyopathy (CCC), but is the key factor causing digestive organic involvement. We investigated the ability of heart rate variability (HRV) for death risk stratification in CCC and compared alterations of HRV in patients with isolated CCC and in those with the mixed form (CCC + digestive involvement). Thirty-one patients with CCC were classified into three risk groups (low, intermediate and high) according to their Rassi score. A single-lead ECG was recorded for a period of 10-20 min, RR series were generated and 31 HRV indices were calculated. The HRV was compared among the three risk groups and regarding the associated digestive involvement. Four machine learning models were created to predict the risk class of patients. RESULTS: Phase entropy is decreased and the percentage of inflection points is increased in patients from the high-, compared to the low-risk group. Fourteen patients had the mixed form, showing decreased triangular interpolation of the RR histogram and absolute power at the low-frequency band. The best predictive risk model was obtained by the support vector machine algorithm (overall F1-score of 0.61). CONCLUSIONS: The mixed form of Chagas' disease showed a decrease in the slow HRV components. The worst prognosis in CCC is associated with increased heart rate fragmentation. The combination of HRV indices enhanced the accuracy of risk stratification. In patients with the mixed form of Chagas disease, a higher degree of sympathetic autonomic denervation may be associated with parasympathetic impairment.

Prolonged dipyridamole administration reduces myocardial perfusion defects in experimental chronic Chagas cardiomyopathy.

BACKGROUND: Myocardial perfusion defects (MPD) due to coronary microvascular dysfunction is frequent in chronic Chagas cardiomyopathy (CCC) and may be involved with development of myocardial damage. We investigated whether MPD precedes left ventricular systolic dysfunction and tested the hypothesis that prolonged use of dipyridamole (DIPY) could reduce MPD in an experimental model of CCC in hamsters. METHODS AND RESULTS: We investigated female hamsters 6-months after T. cruzi infection (baseline condition) and control animals, divided into T. cruzi-infected animals treated with DIPY (CH + DIPY) or placebo (CH + PLB); and uninfected animals treated with DIPY (CO + DIPY) or placebo (CO + PLB). The animals were submitted to echocardiogram and rest SPECT-Sestamibi-Tc99m myocardial perfusion scintigraphy. Next, the animals were treated with DIPY (4 mg/kg bid, intraperitoneal) or saline for 30 days, and reevaluated with the same imaging methods. At baseline, the CH + PLB and CH + DIPY groups showed larger areas of perfusion defect (13.2 ± 13.2% and 17.3 ± 13.2%, respectively) compared with CO + PLB and CO + DIPY (3.8 ± 2.2% e 3.5 ± 2.7%, respectively), P < .05. After treatment, we observed: reduction of perfusion defects only in the CH + DIPY group (17.3 ± 13.2% to 6.8 ± 7.6%, P = .001) and reduction of LVEF in CH + DIPY and CH + PLB groups (from 65.3 ± 9.0% to 53.6 ± 6.9% and from 69.3 ± 5.0% to 54.4 ± 8.6%, respectively, P < .001). Quantitative histology revealed greater extents of inflammation and interstitial fibrosis in both Chagas groups, compared with control group (P < .001), but no difference between Chagas groups (P > .05). CONCLUSIONS: The prolonged use of DIPY in this experimental model of CCC has reduced the rest myocardial perfusion defects, supporting the notion that those areas correspond to viable hypoperfused myocardium.

Appropriate use of echocardiography and relation to clinical decision making in both inpatients and outpatients in a developing country.

BACKGROUND: Use of echocardiography (echo) has exponentially increased in recent decades. Concerned about this scientific society developed appropriate use criteria (AUC). Clinical management still suffers geographical variations, and no objective data are available about echo AUC in developing countries. We aimed to evaluate (1) the appropriateness of referrals and (2) their relation to changes in clinical decision management. METHODS: Prospective analysis of referrals from January to December 2014. Appropriateness and endpoints analyzed in different time points from medical archives. ENDPOINTS: (1) change in the diagnosis, (2) indication for another method to complete the diagnosis, (3) change in clinical treatment, (4) indication for a treatment intervention, or (5) no change in management. Descriptive statistical analysis, Fisher's or chi-square tests, and Cox regression used as appropriate (significance if P < .05). RESULTS: One thousand one hundred referrals were analyzed (55.5 ± 16.1 years, 44.6% male). 80.5% of referrals were appropriate (A), 11.2% "Rarely Appropriate" (RA), and 8.3% "May Be Appropriate" (MBA). Proportion of (A) did not differ between modalities (TTE-80.5% vs TEE-87.7% vs STR-81.2%, P = .67). (A) referrals were more related to clinical decision than (RA)+(MBA) (38.9% [A] vs 15% [RA]+[MBA], P < .001). The most frequent clinical indications of (RA) and (MBA) TTE were reevaluation of ventricular function without clinical change (AUC 10 and 11) and search of infectious endocarditis when low clinical probability (53). CONCLUSIONS: In a developing country, appropriateness of echo was similar to the United States and Europe. However, a significant proportion of referrals were still (RA) or (MBA), with no effect in clinical management. Controlling referrals 10, 11, and 53 can optimize echo use in developing countries.

Echocardiographic Alterations of Cardiac Geometry and Function in Patients with Familial Partial Lipodystrophy. / Alterações Ecocardiográficas da Geometria e da Função Cardíaca em Pacientes com Lipodistrofia Familiar Parcial.

BACKGROUND: Cardiomyopathy associated with partial lipodystrophy (PL) has not been well described yet. OBJECTIVE: To characterize cardiac morphology and function in PL. METHODS: Patients with familial PL and controls were prospectively assessed by transthoracic echocardiography and with speckle-tracking echocardiography (global longitudinal strain, GLS). The relationship between echocardiographic variables and PL diagnosis was tested with regression models, considering the effect of systolic blood pressure (SBP). Significance level of 5% was adopted. RESULTS: Twenty-nine patients with PL were compared to 17 controls. They did not differ in age (p=0.94), gender or body mass index (p= 0.05). Patients with PL had statistically higher SBP (p=0.02) than controls. Also, PL patients had higher left atrial dimension (37.3 ± 4.4 vs. 32.1 ± 4.3 mm, p= 0.001) and left atrial (30.2 ± 7.2 vs. 24.9 ± 9.0 mL/m2,p=0.02), left ventricular (LV) mass (79.3 ± 17.4 vs. 67.1 ± 19.4, p=0.02), and reduced diastolic LV parameters (E' lateral, p= 0.001) (E' septal, p= 0.001), (E/E' ratio, p= 0.02). LV ejection fraction (64.7 ± 4.6 vs. 62.2 ± 4.4 %, p= 0.08) and GLS were not statistically different between groups (-17.1 ± 2.7 vs. -18.0 ± 2.0 %, p= 0.25). There was a positive relationship of left atrium (ß 5.6, p<0.001), posterior wall thickness, (ß 1.3, p=0.011), E' lateral (ß -3.5, p=0.002) and E' septal (ß -3.2, p<0.001) with PL diagnosis, even after adjusted for SBP. CONCLUSION: LP patients have LV hypertrophy, left atrial enlargement, and LV diastolic dysfunction although preserved LVEF and GLS. Echocardiographic parameters are related to PL diagnosis independent of SBP.

FUNDAMENTO: A cardiomiopatia associada à lipodistrofia parcial (LP) ainda não foi bem descrita. OBJETIVO: Caracterizar a morfologia e a função cardíaca na LP. MÉTODOS: Pacientes com LP e controles foram avaliados prospectivamente por ecocardiografia transtorácica e ecocardiografia por speckle-tracking (Strain Longitudinal Global, SLG). A relação entre as variáveis ecocardiográficas e o diagnóstico de LP foi testada com modelos de regressão, considerando o efeito da pressão arterial sistólica (PAS). Adotou-se um nível de significância de 5%. RESULTADOS: Vinte e nove pacientes com LP foram comparados com 17 controles. Eles não se diferiram quanto à idade (p=0,94), sexo ou índice de massa corporal (p= 0,05). Os pacientes com LP apresentaram PAS estatisticamente mais alta (p=0,02) em comparação aos controles. Ainda, os pacientes com LP apresentaram maior dimensão do átrio (37,3 ± 4,4 vs. 32,1 ± 4,3 mm, p= 0,001) e maior volume atrial (30,2 ± 7,2 vs. 24,9 ± 9,0 mL/m2, p=0,02), massa do Ventrículo Esquerdo (VE) (79,3 ± 17,4 vs. 67,1 ± 19,4; p=0,02), e parâmetros sistólicos reduzidos do VE (E' lateral, p= 0,001) (E' septal, p= 0,001), (razão E/E', p= 0,02). A fração de ejeção do VE (64,7 ± 4,6 vs. 62,2 ± 4,4 %, p = 0,08) e o SLG não foram estatisticamente diferentes entre os grupos (-17,1±2,7 vs-18.0 ± 2,0%, p= 0,25). Observou-se uma reação positiva do átrio esquerdo (ß 5,6; p<0,001), espessura da parede posterior (ß 1,3; p=0,011), E' lateral (ß -3,5; p=0,002) e E' septal (ß -3,2; p<0,001) com o diagnóstico de LP, mesmo após o ajuste para a PAS. CONCLUSÃO: Os pacientes com LP apresentam hipertrofia do VE, aumento do átrio esquerdo, e disfunção diastólica do VE apesar de fração de ejeção do VE e SLG preservados. Os parâmetros ecocardiográficos estão relacionados com o diagnóstico de LP, independentemente da PAS.

Cardiac Magnetic Resonance as an Etiological Diagnosis Tool in Recovered Sudden Cardiac Death or Unstable Ventricular Arrhythmia Patients. / Ressonância Magnética Cardíaca como Ferramenta Diagnóstica Etiológica em Pacientes Recuperados de Morte Súbita Cardíaca ou Arritmias Ventriculares Instáveis.

BACKGROUND: Cardiac magnetic resonance (CMR) has an increasing diagnostic relevance in survivors of sudden cardiac death (SCD) or unstable ventricular arrhythmia (UVA) in developed countries. OBJECTIVE: To evaluate retrospectively the additional role of CMR in a developing country where few resources are available, and should be used more effectively. METHODS: The study included SCD or UVA survivors admitted between 2009 and 2019 at a tertiary academic institution referred to CMR. Demographic, clinical, and laboratory data were collected from the medical records. CMR images and reports were reviewed and their impact on the final etiological diagnosis was determined. A descriptive analysis was performed and p<0.05 established as significant. RESULTS: Sixty-four patients, 54.9±15.4 years old, and 42 (71.9%) males. Most events (81.3%) were out of the hospital and ventricular tachycardia was the most common rhythm. Cardiovascular medications were previously used by 55 patients, and beta-blockers were the most used medications (37.5%). Electrocardiogram had electrical inactive areas in 21.9% and all of them had fibrosis at CMR. Mean left ventricular ejection fraction (LVEF) was 44±14%, with 60.9% ≤50% and only 29.7% ≤35%. Late gadolinium enhancement was identified in 71.9%, with a transmural pattern in 43.8%. Chagas cardiomyopathy was the most common etiology (28.1%), followed by ischemic cardiomyopathy (17.2%). Among 26 without a previously identified etiology, CMR could define it (15 patients - 57%). CONCLUSION: In accordance with previous studies in developed countries, CMR was capable of increasing etiological diagnosis and identifying the arrhythmogenic substrate, allowing better care in half of the underdiagnosed patients.

FUNDAMENTO: A ressonância magnética cardíaca (RMC) tem relevância diagnóstica crescente em sobreviventes de morte súbita cardíaca (MSC) ou arritmia ventricular instável (AVI) em países desenvolvidos. OBJETIVO: Procuramos avaliar retrospectivamente o papel adicional da RMC em um país em desenvolvimento com poucos recursos disponíveis e que pode direcionar um uso mais eficaz desses recursos. MÉTODOS: Foram incluídos sobreviventes de MSC ou AVI admitidos entre 2009 e 2019 em uma instituição acadêmica terciária após a realização de RMC. Dados demográficos, clínicos e laboratoriais foram coletados dos prontuários. Imagens e laudos de RMC foram analisados e o impacto disso no diagnóstico etiológico final foi afirmado. Realizou-se análise descritiva e definiu-se p<0,05 como significativo. RESULTADOS: Sessenta e quatro pacientes, 54,9±15,4 anos, sendo 42 (71,9%) do sexo masculino. A maioria dos eventos (81,3%) foi extra-hospitalar e a taquicardia ventricular foi o ritmo mais comum. Medicamentos cardiovasculares foram utilizados anteriormente por 55 pacientes, sendo os betabloqueadores os medicamentos mais utilizados (37,5%). O eletrocardiograma apresentava áreas elétricas inativas em 21,9% e todos apresentavam fibrose na RMC. A média da fração de ejeção do ventrículo esquerdo (FEVE) foi de 44±14%, com 60,9% ≤50% e apenas 29,7% ≤35%. Identificou-se realce tardio com gadolínio em 71,9%, com padrão transmural em 43,8%. A miocardiopatia chagásica foi a etiologia mais comum (28,1%), seguida da miocardiopatia isquêmica (17,2%). Entre 26 sem etiologia previamente identificada, foi possível definir com RMC (15 pacientes - 57%). CONCLUSÃO: De acordo com estudos anteriores em países desenvolvidos, a RMC foi capaz de aumentar o diagnóstico etiológico e identificar o substrato arritmogênico, permitindo melhor atendimento em metade dos pacientes subdiagnosticados.

Use of Cardiopulmonary Exercise Testing to Assess Pulmonary Hypertension in Patients With Rheumatic Mitral Valve Disease: A Comparative Study With Echocardiography.

Rheumatic mitral stenosis (RMS) is still a significant public health problem in low- and middle-income countries. Pulmonary hypertension (PH) is a common consequence of RMS and may be used as a surrogate of disease severity. Cardiopulmonary exercise testing (CPET) provides a comprehensive assessment of the cardiorespiratory systems and can identify indirect signs of PH. To evaluate the relationship between CPET parameters and PH quantified by echocardiography in patients with RMS. This cross-sectional study retrospectively included thirty patients with RMS referred for CPET from 2012 to 2020. Two groups of patients were defined according to echocardiographic-derived pulmonary systolic arterial pressure (PASP): significant PH group (PSAP ≥ 50 mmHg); and non-significant PH group (PSAP < 50 mmHg). A decrease in peak oxygen consumption (VO2) and oxygen pulse predicted (O2PP) was observed in the PH group compared to the non-significant PH group (11.1±2.8 mL/kg/min vs 14.1±2.9 mL/kg/min; P = 0.02; 54±9% vs 67.8±15%; P = 0.02). The PH group exhibited a greater VE/VCO2 nadir rather than non-significant PH group (38±5 vs 32±3; P < 0.001). Receiver operating characteristic (ROC) analysis with O2PP <54% showed sensitivity and specificity of 67% and 90%, respectively. VE/VCO2 nadir ≥ 40 and VO2 peak < 10.8 mL/kg/min showed 44% and 56% of sensitivity and 100% and 90% of specificity respectively. CPET can improve the assessment of disease severity in patients with RMS with high specificity. The presence of higher O2PP, higher VO2 peak, and lower VE/VCO2 nadir highly suggests the absence of significant PH.

Correlation of TcII discrete typing units with severe chronic Chagas cardiomyopathy in patients from various Brazilian geographic regions.

BACKGROUND: Chagas disease (ChD) is caused by Trypanosoma cruzi. The genetic structure of the species is divided into seven distinct genetic groups, TcI to TcVI, and Tcbat, which have shown differences in terms of geographic distribution, biological properties, and susceptibility to drugs. However, the association between genetic variability and clinical forms of ChD has not yet been fully elucidated. The predominance of TcII and TcVI discrete typing units (DTUs) (genetic groups) is known to occur in several Brazilian regions and is associated with both the domestic and the wild cycles of ChD. Thus, this study aimed to verify the genotypes of the parasites present in 330 patients with chronic Chagas cardiomyopathy (CCC) from different Brazilian states attended at the Clinical Hospital of the Ribeirão Preto Medical School and to assess the existence of a correlation between the clinical forms with the main cardiovascular risk factors and the genetics of the parasite. METHODOLOGY PRINCIPAL FINDINGS: All patients with CCC were clinically evaluated through anamnesis, physical examination, biochemical tests, 12-lead electrocardiogram, echocardiogram and chest X-ray. Peripheral blood (5 mL) was collected in guanidine/ethylenediaminetetraacetic acid from each patient for DNA extraction and real-time polymerase chain reaction (PCR) for Chagas disease and genotyping of the parasite in the 7 DTUs. Parasite genotyping was performed using conventional multilocus PCR. Samples of only 175 patients were positive after amplification of the specific genes contained in the T. cruzi genotyping criteria. TcII (64/175), TcVI (9/175), and TcI (3/175) DTUs were predominant, followed by TcII/TcV/TcVI (74/175), and TcII/TcVI (23/175). The TcIII and TcIV DTU´s was detected in only one sample of CCC patients. CONCLUSIONS/SIGNIFICANCE: Our data corroborate previous findings, indicating the predominance of the TcII genotype in patients with CCC of Brazilian origin. Moreover, this study pioneered disclosing a direct correlation between the TcII DTU and severe CCC.

Prospective analysis of myocardial strain through the evolution of Chagas disease in the hamster animal model.

Speckle tracking echocardiography (STE) enables early diagnosis of myocardial damage by evaluating myocardial strain. We aimed to study sequential changes in structural and ventricular functional parameters during Chagas disease (CD) natural history in an animal model. 37 Syrian hamsters were inoculated intraperitoneally with Trypanosoma cruzi (Chagas) and 20 with saline (Control). Echocardiography was performed before the infection (baseline), at 1 month (acute phase), 4, 6, and 8 months (chronic phase) using Vevo 2100 (Fujifilm Inc.) ultrasound system. Left ventricular end-diastolic diameter, Left ventricular end-systolic diameter (LVESD), Left ventricular ejection fraction (LVEF), Global longitudinal (GLS), circumferential (GCS) and radial (GRS) strain were evaluated. Tricuspid annular plane systolic excursion (TAPSE) was used to assess right ventricular function. At 8 months, animals were euthanized and LV myocardial samples were analyzed for quantitation of inflammation and fibrosis. LVEF decreased over time in Chagas group and a difference from Control was detected at 6 months (p-value of groups#time interaction = 0.005). There was a pronounced decrease in GLS, GCS and TAPSE in Chagas group (p-value of groups#time interaction = 0.003 for GLS, < 0.001 for GCS and < 0.009 for TAPSE vs Control) since the first month. LVESD, LVEF and GLS were significantly correlated to the number of inflammatory cells (r = 0.41, p = 0.046; r = - 0.42, p = 0.042; r = 0.41, p = 0.047) but not to fibrosis. In the Syrian hamster model of CD STE parameters (GLS and GCS) showed an early decrease. Changes in LVEF, LVESD, and GLS were correlated to myocardial inflammation but not to fibrosis.

Statins Prescriptions and Lipid Levels in a Tertiary Public Hospital. / Perfil de Prescrição de Estatinas e de Níveis Lipêmicos em Ambulatórios de Hospital Terciário Público.

BACKGROUND: The development of a new class of medications that are highly capable of reducing LDL-cholesterol renewed the interest in the characterization of familial hypercholesterolemia patients. Nevertheless, little is known about the lipid profile of patients in tertiary healthcare centers in Brazil in order to better estimate the real occurrence of familial hypercholesterolemia, with initial suspect of LDL-cholesterol levels above 190 mg/d/L. OBJECTIVES: This study evaluated the lipid profile (total cholesterol and LDL-cholesterol) in ambulatory patients from a general tertiary public hospital. METHODS: Retrospective study comparing prescriptions of statins and lipid profile results. The significance level was established in 5%. RESULTS: In one year, 9,594 individuals received statin prescriptions, of whom 51.5% were females and the mean age was 63.7±12.9 years-old (18 to 100 years-old). Thirty-two medical specialties prescribed statins. Cardiology was responsible for 43% of the total. Nearly 15% of those patients with a prescription did not have a recent total cholesterol result and 1,746 (18%) did not have a recent LDL-cholesterol measurement. The occurrence of the latter between 130 and 190 mg/dL was present in 1,643 (17.1%) individuals, and 228 (2.4%) patients had an LDL-cholesterol ≥190mg/dL among those using statins at distinct doses. Only two statins were used: simvastatin and atorvastatin. The first was prescribed in 77.6% of the prescriptions. CONCLUSION: In this cross-sectional cohort at a tertiary general hospital, statins have been widely prescribed but with little success in achieving recognized levels of control. There is probably a significant number of FH individuals in this cohort that need to be properly diagnosed in order to receive adequate treatment due to its prognostic implications.

FUNDAMENTO: O surgimento de nova classe de medicamentos com elevada capacidade de reduzir o LDL-colesterol (LDL-c) renovou o interesse na caracterização da hipercolesterolemia familiar (HF). Pouco se conhece do perfil lipídico de pacientes em atendimento terciário em nosso meio para caracterizar a real ocorrência de HF, que começa a ser suspeitada com níveis de LDL-c acima de 190mg/dL. OBJETIVOS: O estudo avaliou o perfil lipídico (colesterol total [CT] e LDL-c) de pacientes de hospital público terciário. MÉTODOS: Estudo retrospectivo de avaliação de prescrições de estatinas e resultados dos lipídios. O nível de significância foi estabelecido em 5%. RESULTADOS: Em 1 ano, 9.594 indivíduos receberam prescrição ambulatorial de estatinas, 51,5% do gênero feminino, idade média de 63,7±12,9 anos (18 a 100 anos). Trinta e duas especialidades prescreveram estatinas, sendo a cardiologia responsável por 43%. Cerca de 15% das prescrições não tinham dosagem recente de CT, e 1.746 (18,0%) não apresentavam resultado recente de LDL-c. A ocorrência de LDL-c > 130mg/dL e < 190mg/dL ocorreu em 1.643 (17,1%) casos, e 228 (2,4%) apresentaram LDL-c ≥ 190mg/dL dentre os que utilizavam estatinas nas diversas doses. Apenas duas estatinas foram utilizadas: sinvastatina e atorvastatina, e a primeira foi prescrita em 77,6% das receitas. CONCLUSÃO: Nesta coorte transversal de hospital terciário, foi possível verificar que a prescrição de estatinas é disseminada, mas que a obtenção de metas adequadas de CT e LDL-c não é atingida em grande percentual, e que há, possivelmente, significativo contingente de portadores de HF que necessitariam ser investigados por suas implicações prognósticas.

Prospective study of ventricular function and myocardial deformation related to survival in acute Chagas disease: an experimental animal model.

Chagas disease (CD) has been changing from an endemic Latino-American disease to a condition found outside endemic regions, due to migratory movements. Although often subclinical, its acute phase can be lethal. This study aimed to assess survival during the acute phase of CD and its relationship with ventricular function in an experimental model. To this end, 30 Syrian hamsters were inoculated with Trypanosoma cruzi (IG) and other 15 animals received saline solution (CG). Groups were monitored daily and submitted to echocardiography in two moments: before the challenge and 15 days post-infection. Left ventricular ejection fraction (LVEF) and global longitudinal myocardial strain (GLS) of the LV were measured. The IG was divided into groups of animals with and without clinical signs of disease. ANOVA for mixed models was used to compare ventricular function parameters. Survival analysis was studied using Kaplan-Meier curves and the log-rank test. The follow-up lasted 60 days. LVEF in IG was reduced through time (53.80 to 43.55%) compared to CG (57.86 to 59.73%) (p=0.002). There was also a reduction of GLS (-18.97% to -12.44%) in the IG compared to CG (p=0.012). Twelve animals from IG died compared to one animal from CG. Eleven out of the 12 animals from the IG group died before presenting with clinical signs of infection. Survival was reduced in the IG compared to CG over time (p=0.02). The reduced survival during the acute phase of this experimental model of Chagas disease was related to the significant reduction of LV function. The mortality rate in the IG was higher in the group presenting with clinical signs of infection.

Aspirin plus verapamil relieves angina and perfusion abnormalities in patients with coronary microvascular dysfunction and Chagas disease: a pilot non-randomized study.

INTRODUCTION: Most patients with chronic cardiomyopathy of Chagas disease (CCCD) harbor a secondary cause of coronary microvascular dysfunction (CMD), for which there is no evidence-based therapy. We evaluated the impact of verapamil plus aspirin on symptoms and perfusion abnormalities in patients with CCCD and CMD. METHODS: Consecutive patients with angina pectoris, who had neither coronary artery obstructions nor moderate-severe left ventricular dysfunction (left ventricular ejection fraction > 40%) despite showing wall motion abnormalities on ventriculography, were referred for invasive angiography and tested for Chagas disease. Thirty-two patients with confirmed CCCD and ischemia on stress-rest SPECT myocardial perfusion scintigraphy (MPS) were included. Clinical evaluation, quality of life (EQ-5D/ Seattle Angina Questionnaire), and MPS were assessed before and after 3 months of treatment with oral verapamil plus aspirin (n=26) or placebo (n=6). RESULTS: The mean patient age was 64 years, and 18 (56%) were female. The ischemic index summed difference score (SDS) in MPS was significantly reduced by 55.6% after aspirin+verapamil treatment. A decrease in SDS was observed in 20 (77%) participants, and in 10 participants, no more ischemia could be detected. Enhancements in quality of life were also detected. No change in symptoms or MPS was observed in the placebo group. CONCLUSIONS: This low-cost 3-month treatment for patients diagnosed with CCCD and CMD was safe and resulted in a 55.6% reduction in ischemic burden, symptomatic improvement, and better quality of life.

Correlation between Cardiomegaly on Chest X-Ray and Left Ventricular Diameter on Echocardiography in Patients with Chagas Disease. / Correlação entre Cardiomegalia pela Radiografia de Tórax e Diâmetro do Ventrículo Esquerdo pela Ecocardiografia em Pacientes com Doença de Chagas.

BACKGROUND: Cardiomegaly on chest X-ray is an independent predictor of death in individuals with chronic Chagas cardiomyopathy (CCC). However, the correlation between increased cardiothoracic ratio (CTR) on chest X-ray and left ventricular end-diastolic diameter (LVEDD) on echocardiography is not well established in this population. OBJECTIVES: To assess the relationship between chest X-ray and LVEDD on echocardiography in patients with Chagas disease and its applicability to the Rassi score. METHODS: Retrospective study on 63 Chagas disease outpatients who underwent chest X-ray and echocardiography. Cardiomegaly on chest X-ray was defined as a CTR>0.5. LVEDD was analyzed as a continuous variable. ROC curve was used to evaluate the ability of LVEDD in detecting cardiomegaly by chest X-ray, with a cut-off point defined by the highest sum of sensitivity and specificity. RESULTS: Median age 61 years [interquartile range 48-68], 56% were women. CCC was detected in 58 patients, five patients had the indeterminate form of Chagas disease. Cardiomegaly was detected in 28 patients. The area under the ROC curve for LVEDD was 0.806 (95%CI: 0.692-0.919). The optimal cut-off for LVEDD was 60 mm (sensitivity = 64%, specificity = 89%). The use of LVEDD on echocardiography as a surrogate for CTR on chest X-ray changed the Rassi score values of 14 patients, with a reduction in the presumed risk in 10 of them. CONCLUSION: LVEDD on echocardiography is an appropriate, highly specific parameter to distinguish between the presence and absence of cardiomegaly on chest X-ray in Chagas disease. (Arq Bras Cardiol. 2021; 116(1):68-74).

FUNDAMENTO: Cardiomegalia pela radiografia de tórax (RXT) é preditor independente de morte em indivíduos com cardiomiopatia crônica da doença de Chagas (CCDC). Contudo, a correlação entre o aumento do índice cardiotorácico (ICT) na RXT e do diâmetro telediastólico do ventrículo esquerdo (DDVE) pela ecocardiografia (ECO) nessa população não está bem definida. OBJETIVOS: Analisar a relação entre cardiomegalia pela RXT e DDVE pela ECO em pacientes com doença de Chagas (DC) e sua aplicabilidade ao escore de Rassi. MÉTODOS: Estudo retrospectivo incluiu 63 pacientes ambulatoriais com DC avaliados por RXT e ECO. Cardiomegalia na RXT foi definida como ICT > 0,5. DDVE foi avaliado como variável contínua. Curva ROC foi utilizada para avaliar o potencial do DDVE para identificação de cardiomegalia pela RXT, com ponto de corte definido pela maior somatória de sensibilidade e especificidade. RESULTADOS: Idade mediana = 61 anos [intervalo interquartil: 48-68], 56% mulheres. CCDC foi identificada em 58 pacientes; 5 tinham a forma indeterminada da DC. Cardiomegalia foi detectada em 28 indivíduos. A área sob a curva ROC do DDVE para identificação de cardiomegalia foi de 0,806 (IC 95%: 0,692-0,919). O ponto de corte ótimo para DDVE foi de 60 mm (sensibilidade = 64%, especificidade = 89%). O uso do DDVE pela ECO em substituição ao ICT pela RXT alterou o escore de Rassi em 14 pacientes, e em 10 deles houve redução do risco presumido. CONCLUSÃO: DDVE pela ECO é parâmetro adequado e com alta especificidade para distinguir entre presença e ausência de cardiomegalia na RXT na DC. (Arq Bras Cardiol. 2021; 116(1):68-74).

Implications for Clinical Practice from a Multicenter Survey of Heart Failure Management Centers.

OBJECTIVES: This observational, cross-sectional study based aimed to test whether heart failure (HF)-disease management program (DMP) components are influencing care and clinical decision-making in Brazil. METHODS: The survey respondents were cardiologists recommended by experts in the field and invited to participate in the survey via printed form or email. The survey consisted of 29 questions addressing site demographics, public versus private infrastructure, HF baseline data of patients, clinical management of HF, performance indicators, and perceptions about HF treatment. RESULTS: Data were obtained from 98 centers (58% public and 42% private practice) distributed across Brazil. Public HF-DMPs compared to private HF-DMP were associated with a higher percentage of HF-DMP-dedicated services (79% vs 24%; OR: 12, 95% CI: 94-34), multidisciplinary HF (MHF)-DMP [84% vs 65%; OR: 3; 95% CI: 1-8), HF educational programs (49% vs 18%; OR: 4; 95% CI: 1-2), written instructions before hospital discharge (83% vs 76%; OR: 1; 95% CI: 0-5), rehabilitation (69% vs 39%; OR: 3; 95% CI: 1-9), monitoring (44% vs 29%; OR: 2; 95% CI: 1-5), guideline-directed medical therapy-HF use (94% vs 85%; OR: 3; 95% CI: 0-15), and less B-type natriuretic peptide (BNP) dosage (73% vs 88%; OR: 3; 95% CI: 1-9), and key performance indicators (37% vs 60%; OR: 3; 95% CI: 1-7). In comparison to non- MHF-DMP, MHF-DMP was associated with more educational initiatives (42% vs 6%; OR: 12; 95% CI: 1-97), written instructions (83% vs 68%; OR: 2: 95% CI: 1-7), rehabilitation (69% vs 17%; OR: 11; 95% CI: 3-44), monitoring (47% vs 6%; OR: 14; 95% CI: 2-115), GDMT-HF (92% vs 83%; OR: 3; 95% CI: 0-15). In addition, there were less use of BNP as a biomarker (70% vs 84%; OR: 2; 95% CI: 1-8) and key performance indicators (35% vs 51%; OR: 2; 95% CI: 91,6) in the non-MHF group. Physicians considered changing or introducing new medications mostly when patients were hospitalized or when observing worsening disease and/or symptoms. Adherence to drug treatment and non-drug treatment factors were the greatest medical problems associated with HF treatment. CONCLUSION: HF-DMPs are highly heterogeneous. New strategies for HF care should consider the present study highlights and clinical decision-making processes to improve HF patient care.

Early impairment of myocardial deformation assessed by regional speckle-tracking echocardiography in the indeterminate form of Chagas disease without fibrosis detected by cardiac magnetic resonance.

Chagas disease (CD) will account for 200,000 cardiovascular deaths worldwide over the next 5 years. Early detection of chronic Chagas cardiomyopathy (CCC) is a challenge. We aimed to test if speckle-tracking echocardiography (STE) can detect incipient myocardial damage in CD. METHODS: Among 325 individuals with positive serological tests, 25 (age 55±12yrs) were selected to compose the group with indeterminate form of Chagas disease (IFCD), based on stringent criteria of being asymptomatic and with normal EKG/X-ray studies. This group was compared with a group of 20 patients with CCC (55±11yrs) and a group of 20 non-infected matched control (NC) subjects (48±10yrs). CD patients and NC were submitted to STE and CD patients were submitted to cardiac magnetic resonance (CMR) with late gadolinium administration to detect cardiac fibrosis by the late enhancement technique. Global longitudinal strain (GLS), circumferential (GCS) and radial strain (GRS) were defined as the average of segments measured from three apical view (GLS) and short axis views (GRS and GCS). Regional left ventricular (LV) longitudinal strain (Reg LS) was measured from each of the 17 segments. Twist was measured as systolic peak difference between basal and apical rotation and indexed to LV length to express torsion. RESULTS: STE global indices (GLS, GCS, twist and torsion) were reduced in CCC vs NC (GLS: -14±6.3% vs -19.3±1.6%, p = 0.001; GCS: -13.6±5.2% vs -17.3 ±2.8%; p = 0.008; twist: 8±7° vs 14±7°, p = 0.01 and torsion: 0.96±1°/cm vs 1.9±1°/cm, p = 0.005), but showed no differences in IFCD vs NC. RegLS was reduced in IFCD vs NC in four LV segments: basal-inferior (-16.3±3.3% vs -18.6±2.2%, p = 0.013), basal inferoseptal (-13.1±3.4 vs -15.2±2.7, p = 0.019), mid-inferoseptal (-17.7±3.2 vs -19.4±2, p = 0.032) and mid-inferolateral (-15.2±3.5 vs -17.8±2.8, p = 0.014). These abnormalities in RegLS occurred in the absence of myocardial fibrosis detectable with CMR in nearly 92% of subjects with IFCD, while myocardial fibrosis was present in 65% with CCC. CONCLUSION: RegLS detects early regional impairment of myocardial strain that is independent from fibrosis in IFCD subjects.

Chagas Cardiomyopathy as the Etiology of Suspected Coronary Microvascular Disease. A Comparison Study with Suspected Coronary Microvascular Disease of Other Etiologies. / Estudo Comparativo da Doença Coronariana Microvascular Causada por Doença de Chagas e por Outras Etiologias.

BACKGROUND: Chagas disease (CD) as neglected secondary form of suspected coronary microvascular dysfunction (CMD). OBJECTIVES: Comparison of patients with CMD related to CD (CMD-CE) versus patients with CMD caused by other etiologies (CMD-OE). METHODS: Of 1292 stable patients referred for invasive coronary angiography to elucidate the hemodynamic pattern and the cause of angina as a cardinal symptom in their medical history, 247 presented normal epicardial coronary arteries and 101 were included after strict exclusion criteria. Of those, 15 had suspected CMD-CE, and their clinical, hemodynamic, angiographic and scintigraphic characteristics were compared to those of the other 86 patients with suspected CDM-OE. Level of significance for all comparisons was p < 0.05. RESULTS: Patients with suspected CMD-CE showed most anthropometric, clinical, angiographic hemodynamic and myocardial perfusion abnormalities that were statistically similar to those detected in the remaining 86 patients with suspected CMD-OE. LV diastolic dysfunction, expressed by elevated LV end-diastolic pressure was equally found in both groups. However, as compared to the group of CMD-OE the group with CMD-CE exhibited lower left ventricular ejection fraction (54.8 ± 15.9 vs 61.1 ± 11.9, p= 0.049) and a more severely impaired index of regional wall motion abnormalities (1.77 ± 0.35 vs 1.18 ± 0.26, p= 0.02) respectively for the CMD-OE and CMD-CE groups. CONCLUSION: Chronic Chagas cardiomyopathy was a secondary cause of suspected coronary microvascular disease in 15% of 101 stable patients whose cardinal symptom was anginal pain warranting coronary angiography. Although sharing several clinical, hemodynamic, and myocardial perfusion characteristics with patients whose suspected CMD was due to other etiologies, impairment of LV segmental and global systolic function was significantly more severe in the patients with suspected CMD related to Chagas cardiomyopathy. (Arq Bras Cardiol. 2020; 115(6):1094-1101).

FUNDAMENTO: A doença de Chagas (DC) constitui uma causa potencial negligenciada de doença microvascular coronariana (DMC). OBJETIVOS: Comparar pacientes com DMC relacionada à DC (DMC-DC) com pacientes com DMC ligada a outras etiologias (DMC-OE). MÉTODOS: De 1292 pacientes estáveis, encaminhados para angiografia coronária invasiva para elucidar o padrão hemodinâmico e a causa de angina, 247 apresentaram coronárias subepicárdicas normais, e 101 foram incluídos após aplicação dos critérios de exclusão. Desses, 15 compuseram o grupo de DMC-DC e suas características clínicas, hemodinâmicas, angiográficas, e cintilográficas foram comparadas às do grupo de 86 pacientes com DMC-OE. O nível de significância estatística para todas as comparações adotado foi de 0,05. RESULTADOS: Pacientes com suspeita de DMC-DC apresentaram características antropométricas, clínicas e angiográficas, além de alterações hemodinâmicas e de perfusão miocárdica estatisticamente comparáveis às detectadas nos 86 pacientes com DMC-OE. Disfunção ventricular diastólica, expressa por elevada pressão telediastólica do ventrículo esquerdo, foi igualmente encontrada nos dois grupos. Entretanto, em comparação a esse grupo com DMC-OE, o grupo com DMC-DC exibiu fração de ejeção ventricular esquerda mais baixa (61,1 ± 11,9 vs 54,8 ± 15,9; p= 0,049) e mais elevado escore de mobilidade da parede ventricular (1,77 ± 0,35 vs 1,18 ± 0,26; p= 0,02). CONCLUSÃO: A cardiomiopatia crônica da doença de Chagas esteve associada à etiologia de possível doença microvascular coronariana em 15% de amostra de 101 pacientes estáveis, cujo sintoma principal era angina requerendo elucidação por angiografia invasiva. Embora os grupos DMC-DC e DMC-OE apresentassem características clínicas, hemodinâmicas, e de perfusão miocárdica em comum, a disfunção global e segmentar do ventrículo esquerdo foi mais grave nos pacientes com DMC associada à DC em comparação à DMC por outras etiologias. (Arq Bras Cardiol. 2020; 115(6):1094-1101).

Alterações Ecocardiográficas da Geometria e da Função Cardíaca em Pacientes com Lipodistrofia Familiar Parcial / Echocardiographic Alterations of Cardiac Geometry and Function in Patients with Familial Partial Lipodystrophy

Resumo Fundamento: A cardiomiopatia associada à lipodistrofia parcial (LP) ainda não foi bem descrita. Objetivo: Caracterizar a morfologia e a função cardíaca na LP. Métodos: Pacientes com LP e controles foram avaliados prospectivamente por ecocardiografia transtorácica e ecocardiografia por speckle-tracking (Strain Longitudinal Global, SLG). A relação entre as variáveis ecocardiográficas e o diagnóstico de LP foi testada com modelos de regressão, considerando o efeito da pressão arterial sistólica (PAS). Adotou-se um nível de significância de 5%. Resultados: Vinte e nove pacientes com LP foram comparados com 17 controles. Eles não se diferiram quanto à idade (p=0,94), sexo ou índice de massa corporal (p= 0,05). Os pacientes com LP apresentaram PAS estatisticamente mais alta (p=0,02) em comparação aos controles. Ainda, os pacientes com LP apresentaram maior dimensão do átrio (37,3 ± 4,4 vs. 32,1 ± 4,3 mm, p= 0,001) e maior volume atrial (30,2 ± 7,2 vs. 24,9 ± 9,0 mL/m2, p=0,02), massa do Ventrículo Esquerdo (VE) (79,3 ± 17,4 vs. 67,1 ± 19,4; p=0,02), e parâmetros sistólicos reduzidos do VE (E' lateral, p= 0,001) (E' septal, p= 0,001), (razão E/E', p= 0,02). A fração de ejeção do VE (64,7 ± 4,6 vs. 62,2 ± 4,4 %, p = 0,08) e o SLG não foram estatisticamente diferentes entre os grupos (-17,1±2,7 vs-18.0 ± 2,0%, p= 0,25). Observou-se uma reação positiva do átrio esquerdo (β 5,6; p<0,001), espessura da parede posterior (β 1,3; p=0,011), E' lateral (β -3,5; p=0,002) e E' septal (β -3,2; p<0,001) com o diagnóstico de LP, mesmo após o ajuste para a PAS. Conclusão: Os pacientes com LP apresentam hipertrofia do VE, aumento do átrio esquerdo, e disfunção diastólica do VE apesar de fração de ejeção do VE e SLG preservados. Os parâmetros ecocardiográficos estão relacionados com o diagnóstico de LP, independentemente da PAS.

Abstract Background: Cardiomyopathy associated with partial lipodystrophy (PL) has not been well described yet. Objective: To characterize cardiac morphology and function in PL. Methods: Patients with familial PL and controls were prospectively assessed by transthoracic echocardiography and with speckle-tracking echocardiography (global longitudinal strain, GLS). The relationship between echocardiographic variables and PL diagnosis was tested with regression models, considering the effect of systolic blood pressure (SBP). Significance level of 5% was adopted. Results: Twenty-nine patients with PL were compared to 17 controls. They did not differ in age (p=0.94), gender or body mass index (p= 0.05). Patients with PL had statistically higher SBP (p=0.02) than controls. Also, PL patients had higher left atrial dimension (37.3 ± 4.4 vs. 32.1 ± 4.3 mm, p= 0.001) and left atrial (30.2 ± 7.2 vs. 24.9 ± 9.0 mL/m2,p=0.02), left ventricular (LV) mass (79.3 ± 17.4 vs. 67.1 ± 19.4, p=0.02), and reduced diastolic LV parameters (E' lateral, p= 0.001) (E' septal, p= 0.001), (E/E' ratio, p= 0.02). LV ejection fraction (64.7 ± 4.6 vs. 62.2 ± 4.4 %, p= 0.08) and GLS were not statistically different between groups (-17.1 ± 2.7 vs. -18.0 ± 2.0 %, p= 0.25). There was a positive relationship of left atrium (β 5.6, p<0.001), posterior wall thickness, (β 1.3, p=0.011), E' lateral (β -3.5, p=0.002) and E' septal (β -3.2, p<0.001) with PL diagnosis, even after adjusted for SBP. Conclusion: LP patients have LV hypertrophy, left atrial enlargement, and LV diastolic dysfunction although preserved LVEF and GLS. Echocardiographic parameters are related to PL diagnosis independent of SBP.

Influence of Aerobic Training on The Mechanics of Ventricular Contraction After Acute Myocardial Infarction: A Pilot Study.

The study of myocardial contractility, based on the new anatomical concepts that govern cardiac mechanics, represents a promising strategy of analysis of myocardial adaptations related to physical training in the context of post-infarction. We investigated the influence of aerobic training on physical capacity and on the evaluation parameters of left ventricular contraction mechanics in patients with myocardial infarction. Thirty-one patients (55.1 ± 8.9 years) who had myocardial infarction in the anterior wall were prospectively investigated in three groups: interval training group (ITG) (n = 10), moderate training group (MTG) n = 10) and control group (CG) (n = 10). Before and after 12 weeks of clinical follow-up, patients underwent cardiopulmonary exercise testing and cardiac magnetic resonance imaging. The trained groups performed supervised aerobic training on treadmill, in two different intensities. A statistically significant increase in peak oxygen uptake (VO2) was observed in the ITG (19.2 ± 5.1 at 21.9 ± 5.6 ml/kg/min, p < 0.01) and in the MTG 18.8 ± 3.7 to 21.6 ± 4.5 ml/kg/min, p < 0.01). The GC did not present a statistically significant change in peak VO2. A statistically significant increase in radial strain (STRAD) was observed in the CG: basal STRAD (57.4 ± 16.6 to 84.1 ± 30.9%, p < 0.05), medial STRAD (57.8 ± 27, 9 to 74.3 ± 36.1%, p < 0.05) and apical STRAD (38.2 ± 26.0 to 52.4 ± 29.8%, p < 0.01). The trained groups did not present a statistically significant change of the radial strain. The present study points to a potential clinical application of the parameters of ventricular contraction mechanics analysis, especially radial strain, to discriminate post-infarction myocardial adaptations between patients submitted or not to aerobic training programs.

Ressonância Magnética Cardíaca como Ferramenta Diagnóstica Etiológica em Pacientes Recuperados de Morte Súbita Cardíaca ou Arritmias Ventriculares Instáveis / Cardiac Magnetic Resonance as an Etiological Diagnosis Tool in Recovered Sudden Cardiac Death or Unstable Ventricular Arrhythmia Patients

Resumo Fundamento A ressonância magnética cardíaca (RMC) tem relevância diagnóstica crescente em sobreviventes de morte súbita cardíaca (MSC) ou arritmia ventricular instável (AVI) em países desenvolvidos. Objetivo Procuramos avaliar retrospectivamente o papel adicional da RMC em um país em desenvolvimento com poucos recursos disponíveis e que pode direcionar um uso mais eficaz desses recursos. Métodos Foram incluídos sobreviventes de MSC ou AVI admitidos entre 2009 e 2019 em uma instituição acadêmica terciária após a realização de RMC. Dados demográficos, clínicos e laboratoriais foram coletados dos prontuários. Imagens e laudos de RMC foram analisados e o impacto disso no diagnóstico etiológico final foi afirmado. Realizou-se análise descritiva e definiu-se p<0,05 como significativo. Resultados Sessenta e quatro pacientes, 54,9±15,4 anos, sendo 42 (71,9%) do sexo masculino. A maioria dos eventos (81,3%) foi extra-hospitalar e a taquicardia ventricular foi o ritmo mais comum. Medicamentos cardiovasculares foram utilizados anteriormente por 55 pacientes, sendo os betabloqueadores os medicamentos mais utilizados (37,5%). O eletrocardiograma apresentava áreas elétricas inativas em 21,9% e todos apresentavam fibrose na RMC. A média da fração de ejeção do ventrículo esquerdo (FEVE) foi de 44±14%, com 60,9% ≤50% e apenas 29,7% ≤35%. Identificou-se realce tardio com gadolínio em 71,9%, com padrão transmural em 43,8%. A miocardiopatia chagásica foi a etiologia mais comum (28,1%), seguida da miocardiopatia isquêmica (17,2%). Entre 26 sem etiologia previamente identificada, foi possível definir com RMC (15 pacientes - 57%). Conclusão De acordo com estudos anteriores em países desenvolvidos, a RMC foi capaz de aumentar o diagnóstico etiológico e identificar o substrato arritmogênico, permitindo melhor atendimento em metade dos pacientes subdiagnosticados.

Abstract Background Cardiac magnetic resonance (CMR) has an increasing diagnostic relevance in survivors of sudden cardiac death (SCD) or unstable ventricular arrhythmia (UVA) in developed countries. Objective To evaluate retrospectively the additional role of CMR in a developing country where few resources are available, and should be used more effectively. Methods The study included SCD or UVA survivors admitted between 2009 and 2019 at a tertiary academic institution referred to CMR. Demographic, clinical, and laboratory data were collected from the medical records. CMR images and reports were reviewed and their impact on the final etiological diagnosis was determined. A descriptive analysis was performed and p<0.05 established as significant. Results Sixty-four patients, 54.9±15.4 years old, and 42 (71.9%) males. Most events (81.3%) were out of the hospital and ventricular tachycardia was the most common rhythm. Cardiovascular medications were previously used by 55 patients, and beta-blockers were the most used medications (37.5%). Electrocardiogram had electrical inactive areas in 21.9% and all of them had fibrosis at CMR. Mean left ventricular ejection fraction (LVEF) was 44±14%, with 60.9% ≤50% and only 29.7% ≤35%. Late gadolinium enhancement was identified in 71.9%, with a transmural pattern in 43.8%. Chagas cardiomyopathy was the most common etiology (28.1%), followed by ischemic cardiomyopathy (17.2%). Among 26 without a previously identified etiology, CMR could define it (15 patients - 57%). Conclusion In accordance with previous studies in developed countries, CMR was capable of increasing etiological diagnosis and identifying the arrhythmogenic substrate, allowing better care in half of the underdiagnosed patients.