QDS-COVID: A visual analytics system for interactive exploration of millions of COVID-19 healthcare records in Brazil.

COVID-19 is responsible for the deaths of millions of people around the world. The scientific community has devoted its knowledge to finding ways that reduce the impact and understand the pandemic. In this work, the focus is on analyzing electronic health records for one of the largest public healthcare systems globally, the Brazilian public healthcare system called Sistema Único de Saúde (SUS). SUS collected more than 42 million flu records in a year of the pandemic and made this data publicly available. It is crucial, in this context, to apply analysis techniques that can lead to the optimization of the health care resources in SUS. We propose QDS-COVID, a visual analytics prototype for creating insights over SUS records. The prototype relies on a state-of-the-art datacube structure that supports slicing and dicing exploration of charts and Choropleth maps for all states and municipalities in Brazil. A set of analysis questions drives the development of the prototype and the construction of case studies that demonstrate the potential of the approach. The results include comparisons against other studies and feedback from a medical expert.

Effects of Cranioplasty After Decompressive Craniectomy on Neurological Function and Cerebral Hemodynamics in Traumatic Versus Nontraumatic Brain Injury.

After decompressive craniectomy (DC), cranioplasty (CP) can help to normalize vascular and cerebrospinal fluid circulation besides improving the patient's neurological status. The aim of this study was to investigate the effects of CP on cerebral hemodynamics and on cognitive and functional outcomes in patients with and without a traumatic brain injury (TBI). Over a period of 3 years, 51 patients were included in the study: 37 TBI patients and 14 non-TBI patients. The TBI group was younger (28.86 ± 9.71 versus 45.64 ± 9.55 years, P = 0.0001), with a greater proportion of men than the non-TBI group (31 versus 6, P = 0.011). Both groups had improved cognitive outcomes (as assessed by the Mini-Mental State Examination) and functional outcomes (as assessed by the Barthel Index and Modified Rankin Scale) 90 days after CP. In the TBI group, the mean velocity of blood flow in the middle cerebral artery ipsilateral to the cranial defect increased between the time point before CP and 90 days after CP (34.24 ± 11.02 versus 42.14 ± 10.19 cm/s, P = 0.0001). In conclusion, CP improved the neurological status in TBI and non-TBI patients, but an increment in cerebral blood flow velocity after CP occurred only in TBI patients.

Analysis of FOXP3 gene and protein expressions in renal allograft biopsies and their association with graft outcomes.

BACKGROUND: The transcription factor FOXP3 is increased in acute renal rejection, but its influence on graft outcomes is unclear. This study correlated FOXP3 with dendritic cells and graft outcomes. METHODS: We assessed 96 kidney transplants undergoing allograft biopsy for cause. FOXP3 mRNA was analyzed by real-time polymerase chain reaction (PCR) and FOXP3 protein and DCsCD83(+) by immunohistochemistry. Graft function and survival were assessed at 5 years post-transplantation, as well as by independent predictors of graft loss. RESULTS: Intragraft FOXP3 gene and protein expression were significantly correlated (r = 0.541, p < 0.001). Both FOXP3 mRNA and protein were increased in patients with acute rejection (AR). High expression of FOXP3 mRNA or protein in biopsies did not correlate with clinical variables, but there was a trend to higher positive variation in the glomerular filtration rate (GFR) from biopsy to last follow-up. Patients with FOXP3-mRNA(high) had more DCsCD83(+) in biopsy, but these cells did not associate with AR. Five-year graft survival was not influenced by either FOXP3 mRNA or protein expressions. CONCLUSIONS: FOXP3 mRNA and protein had a good correlation in archival renal graft tissue. Increased FOXP3 expression was found in AR and FOXP3 associated with high numbers of DCs. However, both FOXP3 mRNA and protein was not associated with better allograft outcomes.

Association between time of day for rapid response team activation and mortality.

PURPOSE: To evaluate the frequency of rapid response team (RRT) calls by time of day and their association with in-hospital mortality. MATERIALS AND METHODS: This was a retrospective cohort study of all RRT calls at a tertiary teaching hospital in Porto Alegre, Brazil. Patients were categorized according to the time of initial RRT activation. Activations were classified as daytime (7:00-18:59) or nighttime (19:00-6:59). The primary outcome was in-hospital mortality rate. The secondary outcome was ICU admission within 48 h of RRT assessment. RESULTS: During the study period, 4522 patients were included in the final analysis. Cardiovascular and respiratory changes were more common causes of nighttime activation, whereas neurological and laboratory changes were more common during the daytime. The in-hospital mortality rate was 23.9% (1081/4522). Nighttime RRT calls were not associated with worse outcomes than daytime calls. However, a decrease in the number of calls was observed during nursing handover periods (7:00, 13:00 and 19:00). Two time periods were associated with increased adjusted odds for mortality: 12:00-13:00 (adjusted OR 2.277; 95% CI 1.392-3.725) and 19:00-20:00 (adjusted OR 1.873; CI 1.873; 95% 1.099-3.190). CONCLUSION: We found that nighttime RRT calls were not associated with worse outcomes than daytime RRT calls. However, a decrease in the number of calls and higher mortality was observed during nursing handover periods.

Endothelin-1 and endothelin a receptor immunoreactivity is increased in patients with diabetic nephropathy.

BACKGROUND: Endothelin-1 (ET-1) is associated with progression of renal disease, acting as a vasoconstrictor and growth factor for mesangial cells. ET-1 and endothelin A receptor (ET-RA) might have a role in the development of diabetic nephropathy (DN). The aims of this study were to determine ET-1 and ET-RA expressions in patients with DN and to correlate these expressions with renal function and proteinuria. MATERIALS AND METHODS: This is a cross-sectional study comprising 13 patients with type 2 diabetes mellitus and DN, 10 patients with proteinuric IgA nephropathy, and 13 samples of normal kidney from tumor nephrectomies. Demographic and selected data were collected from medical charts. The distribution and intensity of ET-1 and ET-RA immunostaining in renal biopsies were determined by immunohistochemistry and these correlated with the estimated glomerular filtration rate (eGFR) and proteinuria. RESULTS: Patients with DN and IgA nephropathy on biopsy had markedly increased staining for ET-1 in endothelial cells of glomerular and peritubular capillaries when compared with controls (p < 0.001). ET-RA staining was also more intense and more diffuse in DN and IgA nephropathy than in controls (p = 0.019) and was restricted to tubular epithelial cells. A positive correlation was observed between ET-1 expression and proteinuria (r = 0.634, p = 0.027), but both ET-1 and ET-RA expressions did not correlate with eGFR. CONCLUSION: In this preliminary report, the higher expressions of ET-1 and ET-RA found in both DN and IgA nephropathy suggest a potential role for the endothelin system in DN as well as in other nondiabetic glomerular diseases.

Diagnostic accuracy of multiorgan point-of-care ultrasound compared with pulmonary computed tomographic angiogram in critically ill patients with suspected pulmonary embolism.

BACKGROUND: Critically ill patients have a higher incidence of pulmonary embolism (PE) than non-critically ill patients, yet no diagnostic algorithm has been validated in this population, leading to the overuse of pulmonary artery computed tomographic angiogram (CTA). This study aimed to comparatively evaluate the diagnostic accuracy of point-of-care ultrasound (POCUS) combined with laboratory data versus CTA in predicting PE in critically ill patients. METHODS: A prospective diagnostic accuracy study. Critically ill patients with suspected acute PE undergoing CTA were prospectively enrolled. Demographic and clinical data were collected from electronic medical records. Blood samples were collected, and the Wells and revised Geneva scores were calculated. Standardized multiorgan POCUS and CTA were performed. The discriminatory power of multiorgan POCUS combined with biochemical markers was tested using ROC curves, and multivariate analysis was performed. RESULTS: A total of 88 patients were included, and 37 (42%) had PE. Multivariate analysis showed a relative risk (RR) of PE of 2.79 (95% CI, 1.61-4.84) for the presence of right ventricular (RV) dysfunction, of 2.54 (95% CI, 0.89-7.20) for D-dimer levels >1000 ng/mL, and of 1.69 (95% CI, 1.12-2.63) for the absence of an alternative diagnosis to PE on lung POCUS or chest radiograph. The combination with the highest diagnostic accuracy for PE included the following variables: 1- POCUS transthoracic echocardiography with evidence of RV dysfunction; 2- lung POCUS or chest radiograph without an alternative diagnosis to PE; and 3- plasma D-dimer levels >1000 ng/mL. Combining these three findings resulted in an area under the curve of 0.85 (95% CI, 0.77-0.94), with 50% sensitivity and 96% specificity. CONCLUSIONS: Multiorgan POCUS combined with laboratory data has acceptable diagnostic accuracy for PE compared with CTA. The combined use of these methods might reduce CTA overuse in critically ill patients.

Early prediction of ICU readmissions using classification algorithms.

CONTEXT: Determining which patients are ready for discharge from an Intensive Care Unit (ICU) presents a huge challenge, as ICU readmissions are associated with several negative outcomes such as increased mortality, length of stay, and cost compared to those patients who are not readmitted during their hospital stay. For these reasons, enhancing risk stratification in order to identify patients at high risk of clinical deterioration might benefit and improve the outcomes of critically ill hospitalized patients. Existing work on predicting ICU readmissions relies on information available at the time of discharge, however, in order to be more useful and to prevent complications, predictions need to be made earlier. GOALS: In this work, we investigate the hypothesis that the basal characteristics and information collected at the time of the patient's admission can enable accurate predictions of ICU readmission. MATERIALS AND METHODS: We analyzed an anonymized dataset of 11,805 adult patients from three ICUs in a Brazilian university hospital. After excluding 1879 patients who died during their first ICU admission, our final dataset contained 9,926 patients. Of these, 658 patients (6.6%) had been readmitted to the ICU. The original dataset had 185 attributes, including demographics, length of stay prior to ICU admission, comorbidities, severity indexes, interventions, organ support care during ICU stay and laboratory results. The problem of predicting ICU readmissions was modeled as a binary classification task. We tested eight classification algorithms (including Bayesian algorithms, decision trees, rule-based, and ensemble methods) over different sets of attributes and evaluated their results based on six metrics. RESULTS: Predictions made solely based on the attributes collected at the admission are highly accurate. Their quality in terms of prediction is no different from predictions made using the complete set of attributes for our dataset and for a subset of attributes selected by a feature selection method. Furthermore, our AUROC score of 0.91 (95% CI [0.89,0.92]) is higher than existing results published in the literature for other datasets. DISCUSSION AND CONCLUSION: The results confirm our hypothesis. Our findings suggest that early markers can be used to anticipate patients at high risk of clinical deterioration after ICU discharge.

Antimicrobial stewardship: The influence of behavioral nudging on renal-function-based appropriateness of dosing.

Failure to adjust doses may contribute to adverse events. We evaluated the effectiveness of providing the estimated glomerular filtration rate on appropriateness of dosing for antimicrobials. The approach increased appropriateness of dosing from 33.9% to 41.4% (P < .001). Nudging prescription behavior can boost strategies for adequate antimicrobial prescription.

Diagnostic Accuracy of CD64 for Sepsis in Emergency Department.

INTRODUCTION: Sepsis is a systemic inflammatory response to suspected or confirmed infection. Clinical evaluations are essential for its early detection and treatment. Blood cultures may take as long as 2 days to yield a result and are not always reliable. However, recent studies have suggested that neutrophil CD64 expression may be a sensitive and specific alternative for the diagnosis of systemic infection. OBJECTIVE: The objective of the study was to analyze the difference in CD64 values between subjects with systemic inflammatory response syndrome (SIRS), suspected or confirmed sepsis, who meet diagnostic criteria for SIRS upon arriving at an emergency department. MATERIALS AND METHODS: This was a prospective observational cohort study, an accuracy study of CD64 prospectively evaluated. The sample consisted of 109 patients aged 18 years with criteria for SIRS on arrival to emergency department. CD64 expression was measured within 6 h of hospital admission and once again after 48 h. RESULTS: ROC curve analysis suggested that a cutoff of 1.45 for CD64 expression could diagnose sepsis with a sensitivity of 0.85, a specificity of 0.75, an accuracy of 82.08%, a positive predictive value of 0.96, a negative predictive value of 0.38 and a positive likelihood ratio of 3.33. The area under the curve was 0.83. CONCLUSION: CD64 seems to be a useful, sensitive, and specific biomarker in discriminating between SIRS and sepsis.

Incidence of uterine post abortion infection at Hospital de Clínicas de Porto Alegre. Is prophylactic antibiotic necessary?

OBJECTIVE: To identify the incidence of pelvic infection after miscarriage undergoing uterine evacuation in a tertiary hospital in southern Brazil and to compare with the international literature. METHODS: we reviewed electronic medical records of the Hospital de Clinicas de Porto Alegre of all patients who underwent uterine evacuation for miscarriage between August 2008 and January 2012 were reviewed. We included all patients submitted to uterine curettage due to abortion and who had outpatient visits for review after the procedure. We calculated emographic and laboratory data of the study population, number needed for treatment (NNT) and number needed to harm (NNH). RESULTS: of the 857 revised electronic medical records, 377 patients were subjected to uterine evacuation for miscarriage; 55 cases were lost to follow-up, leaving 322 cases that were classified as not infected abortion on admission. The majority of the population was white (79%); HIV prevalence and positive VDRL was 0.3% and 2%, respectively. By following these 322 cases for a minimum of seven days, it was found that the incidence of post-procedure infection was 1.8% (95% CI 0.8 to 4). The NNT and NNH calculated for 42 months were 63 and 39, respectively. CONCLUSION: The incidence of post-abortion infection between August 2008 to January 2012 was 1.8% (0.8 to 4).

Expression patterns of B cells in acute kidney transplant rejection.

OBJECTIVES: To evaluate B-cell expression patterns and association with function and survival in dysfunctional kidney allografts. MATERIALS AND METHODS: There were 110 kidney transplant recipients included who had for-cause biopsies. Demographic and transplant data were collected. Immunostaining for B cells, plasma cells, and C4d was performed by the immunoperoxidase technique in paraffin-embedded samples. Circulating antihuman leukocyte antigen donor-specific antibodies were detected in a single-antigen assay at biopsy. The main outcomes were kidney graft survival and function. The patients were evaluated in 3 groups according to the Banff classification: no rejection (40 patients), T-cell-mediated rejection (50 patients), and antibody-mediated rejection (20 patients). RESULTS: The CD138-positive plasma cell-rich infiltrates predominated in antibody-mediated rejection and were associated with stronger reactivity against panel antibodies (r = 0.41; P ≤ .001) and positive donor-specific antibodies (r = 0.32; P ≤ .006). The CD20-positive lymphocytes were associated with T-cell-mediated rejection, increased human leukocyte antigen mismatch, and frequency of retransplant. The CD138-positive cell infiltrates also were significantly greater in patients who had late than early rejection. There was no correlation between cellular CD20 and CD138 expression, and neither CD20 nor CD138 predicted worse graft function or survival. Other markers of antibody-mediated rejection such as C4d and donor-specific antibodies were associated with worse graft function and survival at 4 years after transplant. In multivariate analysis, C4d was the only risk factor associated with graft loss. CONCLUSIONS: After kidney transplant, CD20-positive B-cell infiltrates were associated with T-cell-mediated rejection, and CD138-positive plasma cells were associated with antibody-mediated rejection. Graft loss was associated with the presence of C4d.

Ventricular arrhythmias and left ventricular hypertrophy in hypertrophic cardiomyopathy.

BACKGROUND: In hypertrophic cardiomyopathy (HCM), the degree of left ventricular hypertrophy (LVH) could influence the development of ventricular arrhythmias. OBJECTIVE: In HCM, analyze the association between the occurrence of ventricular arrhythmias determined by Holter electrocardiogram (ECG-Holter) and the degree of LVH determined by maximum wall thickness (MWT) in echocardiography and body mass index (BMI). METHODS: Fifty-four consecutive patients with HCM underwent 24-hour ECG-Holter and echocardiography for assessment of level of LVH through MWT and BMI. Two levels were established for the occurrence of Ventricular Arrhythmias: I - alone or paired extrasystoles and II - Non- Sustained Ventricular Tachycardia (NSVT). RESULTS: In 13 patients (24%) with NSVT (level II), there was a higher frequency of MWT of the left ventricle (LV) > 21 mm (n = 10, 77%, 25 ± 4 mm) and LLLV = 144 g/m² (n = 10, 77%, 200 ± 30 g/m²), in comparison with those presenting with extrasystole arrhythmias (level I) (n = 41, 76%), in which these measures were identified in, respectively, 37 % (n= 15, 23 ± 1 mm), p = 0.023, and 39% (n = 16, 192 ± 53 g / m²) of the cases (p = 0.026). The cut-off values mentioned were determined by the ROC curve with a confidence interval of 95%. NSVT was more common in patients with MWTLV > 21 mm and LLLV > 144 g/m² (8 of 13, 62%) than in those with (4 of 13, 31%) or without (1 of 13; 8%) echocardiographic variables above cut-off values (p = 0.04). CONCLUSION: In HCM, occurrence of ventricular arrhythmias by Holter was associated with the degree of LVH assessed by echocardiography through MWT and BMI.

The diagnosis of left ventricular outflow tract obstruction in hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy is a prevalent genetic disease characterized by left ventricular hypertrophy, presenting dynamic obstruction of outflow tract with subaortic gradient happening at rest in 30% of the cases. It is attributed to the intricate interaction between the anterior mitral leaflet, the interventricular septum and altered flow vectors generated in left ventricle along with changes in outflow tract geometry. Mitral regurgitation in varying degrees is found with or without association with structural deformities of the valve apparatus. The exercise echocardiogram evidences latent obstruction easily induced by exercise in 60 to 75% of non-obstructive forms. The determination of the gradient under this condition must be considered in routine investigation of patients with mild or no obstruction at rest. The evaluation of hypertrophic cardiomyopathy incorporates methods based on the ultrasound image, which, along with MRI, allow recognizing ventricular obstruction generating mechanisms, thus facilitating the diagnosis and management of obstructive and latent obstructive forms.

Resultados da terapia dupla (interferon e ribavirina) para Hepatite C em um centro de referência no sul do Brasil: um estudo da vida real / Outcomes of double therapy (interferon and ribavirin) for Hepatits C in an excellence center in southern Brazil: a real-life study

Introdução: A Hepatite C tem uma prevalência estimada de cerca de 170 milhões de pessoas mundialmente e cursa com grande morbimortalidade. O tratamento deste deste vírus tem se alterado significativamente nos últimos anos, porém, no Brasil, ainda imperam os tratamentos baseados em interferon convencional ou em interferon -peguilado associado à ribavirina. Métodos: Estudo de coorte, retrospectivo, conduzido no Hospital de Clínicas de Porto Alegre. Foram incluídos 237 pacientes com Hepatite C tratados com interferon e ribavirina ou com interferon -peguilado e ribavirina. Resultados: A taxa global de resposta virológica sustentada obtida foi de 33,33%, sendo 37,93% nos pacientes com regime baseado em interferon convencional e 32,69% nos pacientes com interferon -peguilado. A análise demonstrou uma maior taxa de resposta virológica sustentada entre os pacientes que apresentaram, à análise genética, expressão CC do polimorfismo do IL 28B.

Introduction: Hepatitis C affects approximately 170 million people worldwide and it results in great morbidity and mortality. The virus treatment has changed significantly. However, in Brazil, treatments based on conventional interferon or pegylated-interferon associated with ribavirin are still the most usual ones. Methods: Retrospective cohort study conducted at Hospital de Clínicas de Porto Alegre. That included 237 patients treated for hepatitis C with interferon and ribavirin or pegylated--interferon and ribavirin. Results: The overall rate of sustained virologic response was 33.33%, with a rate of 37.93% in patients treated with conventional interferon and 32.69% in with pegylatedinterrferon. The analysis showed a higher rate of sustained virologic response among patients who, in genetic analysis, CC expression of IL28B polymorphism.

Incidence of uterine post abortion infection at Hospital de Clínicas de Porto Alegre. Is prophylactic antibiotic necessary? / Incidência de infecção pós-abortamento no Hospital de Clínicas de Porto Alegre. O antibiótico profilático é necessário?

OBJECTIVE: To identify the incidence of pelvic infection after miscarriage undergoing uterine evacuation in a tertiary hospital in southern Brazil and to compare with the international literature. METHODS: we reviewed electronic medical records of the Hospital de Clinicas de Porto Alegre of all patients who underwent uterine evacuation for miscarriage between August 2008 and January 2012 were reviewed. We included all patients submitted to uterine curettage due to abortion and who had outpatient visits for review after the procedure. We calculated emographic and laboratory data of the study population, number needed for treatment (NNT) and number needed to harm (NNH). RESULTS: of the 857 revised electronic medical records, 377 patients were subjected to uterine evacuation for miscarriage; 55 cases were lost to follow-up, leaving 322 cases that were classified as not infected abortion on admission. The majority of the population was white (79%); HIV prevalence and positive VDRL was 0.3% and 2%, respectively. By following these 322 cases for a minimum of seven days, it was found that the incidence of post-procedure infection was 1.8% (95% CI 0.8 to 4). The NNT and NNH calculated for 42 months were 63 and 39, respectively. CONCLUSION: The incidence of post-abortion infection between August 2008 to January 2012 was 1.8% (0.8 to 4). .

OBJETIVO: Identificar a incidência de infecção pélvica após aborto espontâneo submetido a esvaziamento uterino num hospital terciário do sul do Brasil e comparar com a literatura internacional. MÉTODOS: Os prontuários eletrônicos do Hospital de Clínicas de Porto Alegre de todas as pacientes que foram submetidas ao esvaziamento uterino por abortamento entre agosto de 2008 e Janeiro de 2012 foram revisados. Foram incluídas no estudo todas as pacientes submetidas à curetagem uterina por abortamento e que tiveram consultas ambulatoriais de revisão após o procedimento. Os dados demográficos e laboratoriais da população estudada, number needed for treatment (NNT) e o number needed to harm (NNH) foram calculados. RESULTADOS: Dos 857 prontuários eletrônicos revistos, 377 pacientes foram submetidas ao esvaziamento uterino por abortamento; 55 casos foram perdidos no seguimento, restando 322 casos que foram classificados como aborto não infectado na admissão. A maioria da população era da raça branca (79%); a prevalência de HIV e VDRL positivos foi de 0,3 e 2%, respectivamente. No seguimento desses 322 casos, num período mínimo de 7 dias, verificou-se que a incidência de infecção pós-procedimento foi de 1,8% (IC95%0,8 a 4). O NNT e o NNH calculado para 42 meses foi de 63 e 39, respectivamente. CONCLUSÃO: A incidência de infecção pós-aborto entre agosto de 2008 a janeiro de 2012 foi de 1,8% (0,8 a 4). .

Arritmias ventriculares e hipertrofia ventricular esquerda na cardiomiopatia hipertrófica / Ventricular arrhythmias and left ventricular hypertrophy in hypertrophic cardiomyopathy

FUNDAMENTO: Na Cardiomiopatia Hipertrófica (CMH), o grau de Hipertrofia Ventricular Esquerda (HVE) poderia influenciar o desenvolvimento de arritmias ventriculares. OBJETIVO: Analisar, na CMH, a associação entre a ocorrência de arritmias ventriculares no eletrocardiograma-Holter (ECG-Holter) e o grau de HVE determinado ao ecocardiograma pela espessura parietal máxima (EPM) e Índice de Massa (IM). MÉTODOS: Cinquenta e quatro pacientes consecutivos com CMH realizaram ECG-Holter de 24 horas e ecocardiograma para avaliação do grau de HVE através da EPM e IM. Foram estabelecidos dois níveis para a ocorrência de arritmias ventriculares: I - extrassístoles isoladas ou pareadas e II - Taquicardia Ventricular Não Sustentada (TVNS). RESULTADOS: Nos 13 pacientes (24%) com TVNS (nível II), houve maior frequência de EPM do ventrículo esquerdo (VE) > 21 mm (n = 10, 77%; 25 ± 4 mm) e IMVE > 144 g/m² (n = 10, 77%; 200 ± 30 g/m²), em relação àqueles que apresentavam apenas arritmia extrassistólica (nível I) (n = 41, 76%), em que essas medidas foram identificadas em, respectivamente, 37% (n = 15, 23 ± 1 mm), p = 0,023, e 39% (n = 16, 192 ± 53 g/m²) dos casos, p = 0,026. Os citados valores de corte foram determinados por curva ROC com intervalo de confiança de 95%. O registro de TVNS foi mais comum em pacientes com EPMVE > 21 mm e IMVE > 144 g/m² (8 de 13; 62%), do que naqueles com uma (4 de 13; 31%) ou nenhuma (1 de 13; 8%) variável ecocardiográfica acima dos valores de corte, p = 0,04. CONCLUSÃO: A ocorrência de arritmias ventriculares no Holter associou-se, na CMH, ao grau de HVE, avaliado pelo ecocardiograma através da respectiva EPM e IM.

BACKGROUND: In hypertrophic cardiomyopathy (HCM), the degree of left ventricular hypertrophy (LVH) could influence the development of ventricular arrhythmias. OBJECTIVE: In HCM, analyze the association between the occurrence of ventricular arrhythmias determined by Holter electrocardiogram (ECG-Holter) and the degree of LVH determined by maximum wall thickness (MWT) in echocardiography and body mass index (BMI). METHODS: Fifty-four consecutive patients with HCM underwent 24-hour ECG-Holter and echocardiography for assessment of level of LVH through MWT and BMI. Two levels were established for the occurrence of Ventricular Arrhythmias: I - alone or paired extrasystoles and II - Non- Sustained Ventricular Tachycardia (NSVT). RESULTS: In 13 patients (24%) with NSVT (level II), there was a higher frequency of MWT of the left ventricle (LV) > 21 mm (n = 10, 77%, 25 ± 4 mm) and LLLV = 144 g/m² (n = 10, 77%, 200 ± 30 g/m²), in comparison with those presenting with extrasystole arrhythmias (level I) (n = 41, 76%), in which these measures were identified in, respectively, 37 % (n= 15, 23 ± 1 mm), p = 0.023, and 39% (n = 16, 192 ± 53 g / m²) of the cases (p = 0.026). The cut-off values mentioned were determined by the ROC curve with a confidence interval of 95%. NSVT was more common in patients with MWTLV > 21 mm and LLLV > 144 g/m² (8 of 13, 62%) than in those with (4 of 13, 31%) or without (1 of 13; 8%) echocardiographic variables above cut-off values (p = 0.04). CONCLUSION: In HCM, occurrence of ventricular arrhythmias by Holter was associated with the degree of LVH assessed by echocardiography through MWT and BMI.

O diagnóstico da obstrução da via de saída do ventrículo esquerdo na cardiomiopatia hipertrófica / The diagnosis of left ventricular outflow tract obstruction in hypertrophic cardiomyopathy

A cardiomiopatia hipertrófica é uma doença genética prevalente caracterizada por hipertrofia ventricular esquerda, em que obstrução dinâmica da via de saída com geração de gradiente subaórtico incide em repouso em 30% dos casos. A obstrução é atribuida complexa interação entre o folheto anterior mitral, o septo interventricular e vetores anômalos de fluxo gerados no ventrículo esquerdo aliada a modificações na geometria da via de saída. Regurgitação mitral em grau variável é detectada associada ou não a deformidades estruturais do aparelho valvar. O ecocardiograma de esforço demonstra obstrução latente facilmente induzida por exercício em 60 a 75% das formas não obstrutivas. A determinação do gradiente nessas condições impõe-se na investigação de rotina dos pacientes com obstrução leve ou ausente em repouso. A avaliação da cardiomiopatia hipertrófica incorpora métodos de imagem baseados no ultrassom, os quais, adicionados ressonância magnética, possibilitam o reconhecimento de mecanismos geradores de obstrução ventricular, de modo a favorecer o diagnóstico e o manejo das formas obstrutivas e obstrutivas latentes.

Hypertrophic cardiomyopathy is a prevalent genetic disease characterized by left ventricular hypertrophy, presenting dynamic obstruction of outflow tract with subaortic gradient happening at rest in 30% of the cases. It is attributed to the intricate interaction between the anterior mitral leaflet, the interventricular septum and altered flow vectors generated in left ventricle along with changes in outflow tract geometry. Mitral regurgitation in varying degrees is found with or without association with structural deformities of the valve apparatus. The exercise echocardiogram evidences latent obstruction easily induced by exercise in 60 to 75% of non-obstructive forms. The determination of the gradient under this condition must be considered in routine investigation of patients with mild or no obstruction at rest. The evaluation of hypertrophic cardiomyopathy incorporates methods based on the ultrasound image, which, along with MRI, allow recognizing ventricular obstruction generating mechanisms, thus facilitating the diagnosis and management of obstructive and latent obstructive forms.