RESUMO
BACKGROUND: Measurement of peak velocities is important in the evaluation of heart failure. This study compared the performance of automated 4D flow cardiac MRI (CMR) with traditional transthoracic Doppler echocardiography (TTE) for the measurement of mitral inflow peak diastolic velocities. METHODS: Patients with Doppler echocardiography and 4D flow cardiac magnetic resonance data were included retrospectively. An established automated technique was used to segment the left ventricular transvalvular flow using short-axis cine stack of images. Peak mitral E-wave and peak mitral A-wave velocities were automatically derived using in-plane velocity maps of transvalvular flow. Additionally, we checked the agreement between peak mitral E-wave velocity derived by 4D flow CMR and Doppler echocardiography in patients with sinus rhythm and atrial fibrillation (AF) separately. RESULTS: Forty-eight patients were included (median age 69 years, IQR 63 to 76; 46% female). Data were split into three groups according to heart rhythm. The median peak E-wave mitral inflow velocity by automated 4D flow CMR was comparable with Doppler echocardiography in all patients (0.90 ± 0.43 m/s vs 0.94 ± 0.48 m/s, P = 0.132), sinus rhythm-only group (0.88 ± 0.35 m/s vs 0.86 ± 0.38 m/s, P = 0.54) and in AF-only group (1.33 ± 0.56 m/s vs 1.18 ± 0.47 m/s, P = 0.06). Peak A-wave mitral inflow velocity results had no significant difference between Doppler TTE and automated 4D flow CMR (0.81 ± 0.44 m/s vs 0.81 ± 0.53 m/s, P = 0.09) in all patients and sinus rhythm-only groups. Automated 4D flow CMR showed a significant correlation with TTE for measurement of peak E-wave in all patients group (r = 0.73, P < 0.001) and peak A-wave velocities (r = 0.88, P < 0.001). Moreover, there was a significant correlation between automated 4D flow CMR and TTE for peak-E wave velocity in sinus rhythm-only patients (r = 0.68, P < 0.001) and AF-only patients (r = 0.81, P = 0.014). Excellent intra-and inter-observer variability was demonstrated for both parameters. CONCLUSION: Automated dynamic peak mitral inflow diastolic velocity tracing using 4D flow CMR is comparable to Doppler echocardiography and has excellent repeatability for clinical use. However, 4D flow CMR can potentially underestimate peak velocity in patients with AF.
Assuntos
Fibrilação Atrial , Valva Mitral , Humanos , Feminino , Idoso , Masculino , Estudos Retrospectivos , Valva Mitral/diagnóstico por imagem , Ecocardiografia Doppler/métodos , Imageamento por Ressonância Magnética , Ecocardiografia , Fibrilação Atrial/diagnóstico por imagem , Velocidade do Fluxo SanguíneoRESUMO
OBJECTIVE: To investigate whether left atrial (LA) volume and left ventricular filling pressure (LVFP) assessed by cardiovascular magnetic resonance (CMR) change during adenosine delivered myocardial hyperaemia as part of a first-pass stress perfusion study. METHODS AND RESULTS: We enrolled 33 patients who had stress CMR. These patients had a baseline four-chamber cine and stress four-chamber cine, which was done at peak myocardial hyperaemic state after administering adenosine. The left and right atria were segmented in the end ventricular diastolic and systolic phases. Short-axis cine stack was segmented for ventricular functional assessment. At peak hyperaemic state, left atrial end ventricular systolic volume just before mitral valve opening increased significantly from baseline in all (91 ± 35ml vs. 81 ± 33ml, P = 0.0002), in males only (99 ± 35ml vs. 88 ± 33ml, P = 0.002) and females only (70 ± 26ml vs. 62 ± 22ml, P = 0.02). The right atrial end ventricular systolic volume increased less significantly from baseline (68 ± 21ml vs. 63 ± 20ml, P = 0.0448). CMR-derived LVFP (equivalent to pulmonary capillary wedge pressure) increased significantly at the peak hyperaemic state in all (15.1 ± 2.9mmHg vs. 14.4 ± 2.8mmHg, P = 0.0002), females only (12.9 ± 2.1mmHg vs. 12.3 ± 1.9mmHg, P = 0.029) and males only (15.9 ± 2.8mmHg vs. 15.2 ± 2.7mmHg, P = 0.002) cohorts. CONCLUSION: Left atrial volume assessment by CMR can measure acute and dynamic changes in preloading conditions on the left ventricle. During adenosine administered first-pass perfusion CMR, left atrial volume and LVFP rise significantly.
Assuntos
Fibrilação Atrial , Hiperemia , Masculino , Feminino , Humanos , Átrios do Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética , Perfusão , Volume Sistólico , Imagem Cinética por Ressonância Magnética/métodos , Função Ventricular EsquerdaRESUMO
Background and Objectives: The heart is the organ with the highest metabolic demand in the body, and it relies on high ATP turnover and efficient energy substrate utilisation in order to function normally. The derangement of myocardial energetics may lead to abnormalities in cardiac metabolism, which herald the symptoms of heart failure (HF). In addition, phosphorus magnetic resonance spectroscopy (31P MRS) is the only available non-invasive method that allows clinicians and researchers to evaluate the myocardial metabolic state in vivo. This review summarises the importance of myocardial energetics and provides a systematic review of all the available research studies utilising 31P MRS to evaluate patients with a range of cardiac pathologies. Materials and Methods: We have performed a systematic review of all available studies that used 31P MRS for the investigation of myocardial energetics in cardiovascular disease. Results: A systematic search of the Medline database, the Cochrane library, and Web of Science yielded 1092 results, out of which 62 studies were included in the systematic review. The 31P MRS has been used in numerous studies and has demonstrated that impaired myocardial energetics is often the beginning of pathological processes in several cardiac pathologies. Conclusions: The 31P MRS has become a valuable tool in the understanding of myocardial metabolic changes and their impact on the diagnosis, risk stratification, and prognosis of patients with cardiovascular diseases.
Assuntos
Doenças Cardiovasculares , Insuficiência Cardíaca , Humanos , Fósforo , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Miocárdio/metabolismo , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/metabolismo , Metabolismo EnergéticoRESUMO
Despite the strict indications for cardiac resynchronization therapy (CRT) implantation, a significant proportion of patients will fail to adequately respond to the treatment. This systematic review aims to present the existing evidence about the role of cardiac magnetic resonance (CMR) in identifying patients who are likely to respond better to the CRT. A systematic search in the MedLine database and Cochrane Library from their inception to August 2021 was performed, without any limitations, by two independent investigators. We considered eligible observational studies or randomized clinical trials (RCTs) that enrolled patients > 18 years old with heart failure (HF) of ischaemic or non-ischaemic aetiology and provided data about the association of baseline CMR variables with clinical or echocardiographic response to CRT for at least 3 months. This systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA Statement). Following our search strategy, 47 studies were finally included in our review. CMR appears to have an additive role in identifying the subgroup of patients who will respond better to CRT. Specifically, the presence and the extent of myocardial scar were associated with increased non-response rates, while those with no scar respond better. Furthermore, existing data show that scar location can be associated with CRT response rates. CMR-derived markers of mechanical desynchrony can also be used as predictors of CRT response. CMR data can be used to optimize the position of the left ventricular lead during the CRT implantation procedure. Specifically, positioning the left ventricular lead in a branch of the coronary sinus that feeds an area with transmural scar was associated with poorer response to CRT. CMR can be used as a non-invasive optimization tool to identify patients who are more likely to achieve better clinical and echocardiographic response following CRT implantation.
Assuntos
Terapia de Ressincronização Cardíaca , Insuficiência Cardíaca , Adolescente , Terapia de Ressincronização Cardíaca/métodos , Cicatriz/patologia , Cicatriz/terapia , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/terapia , Humanos , Imagem Cinética por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Resultado do TratamentoRESUMO
Increasingly, dynamic magnetic resonance imaging (MRI) has potential as a noninvasive and accessible tool for diagnosing and monitoring gastrointestinal motility in healthy and diseased bowel. However, current MRI methods of measuring bowel motility have limitations: requiring bowel preparation or long acquisition times; providing mainly surrogate measures of motion; and estimating bowel-wall movement in just two dimensions. In this proof-of-concept study we apply a method that provides a quantitative measure of motion within the bowel, in both two and three dimensions, using existing, vendor-implemented MRI pulse sequences with minimal bowel preparation. This method uses a minimised cost function to fit linear vectors in the spatial and temporal domains. It is sensitised to the spatial scale of the bowel and aims to address issues relating to the low signal-to-noise in high-temporal resolution dynamic MRI scans, previously compensated for by performing thick-slice (10-mm) two-dimensional (2D) coronal scans. We applied both 2D and three-dimensional (3D) scanning protocols in two healthy volunteers. For 2D scanning, analysis yielded bi-modal velocity peaks, with a mean antegrade motion of 5.5 mm/s and an additional peak at ~9 mm/s corresponding to longitudinal peristalsis, as supported by intraoperative data from the literature. Furthermore, 3D scans indicated a mean forward motion of 4.7 mm/s, and degrees of antegrade and retrograde motion were also established. These measures show promise for the noninvasive assessment of bowel motility, and have the potential to be tuned to particular regions of interest and behaviours within the bowel.
Assuntos
Motilidade Gastrointestinal , Imageamento por Ressonância Magnética , Algoritmos , Humanos , Imageamento por Ressonância Magnética/métodos , Movimento (Física) , MovimentoRESUMO
PURPOSE OF REVIEW: This review summarises the literature data and provides an overview of the role and impact of the use of renin-angiotensin-aldosterone system (RAAS) inhibitors in patients with coronavirus disease 2019 (COVID-19) infection. RECENT FINDINGS: The angiotensin-converting enzyme 2 (ACE2) has a key role in the regulation of the RAAS pathway, downregulating angiotensin II and attenuating inflammation, vasoconstriction and oxidative stress. Additionally, it plays an instrumental part in COVID-19 infection as it facilitates the cell entry of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and enables its replication. The use and role of RAAS inhibitors therefore during the COVID-19 pandemic have been intensively investigated. Although it was initially assumed that RAAS inhibitors may relate to worse clinical outcomes and severe disease, data from large studies and meta-analyses demonstrated that they do not have an adverse impact on clinical outcomes or prognosis. On the contrary, some experimental and retrospective observational cohort studies showed a potential protective mechanism, although this effect remains to be seen in large clinical trials.
Assuntos
Tratamento Farmacológico da COVID-19 , Hipertensão , Aldosterona/metabolismo , Angiotensina II/metabolismo , Antagonistas de Receptores de Angiotensina/farmacologia , Antagonistas de Receptores de Angiotensina/uso terapêutico , Enzima de Conversão de Angiotensina 2 , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Humanos , Hipertensão/tratamento farmacológico , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Pandemias , Peptidil Dipeptidase A/metabolismo , Renina/metabolismo , Sistema Renina-Angiotensina/fisiologia , Estudos Retrospectivos , SARS-CoV-2RESUMO
AIMS: The aim of this study is to evaluate temporal trends, treatment, and clinical outcomes of patients who present with an acute myocardial infarction (AMI) and have a current or historical diagnosis of cancer, according to cancer type and presence of metastases. METHODS AND RESULTS: Data from 6 563 255 patients presenting with an AMI between 2004 and 2014 from the US National Inpatient Sample (NIS) database were analysed. A total of 5 966 955 had no cancer, 186 604 had current cancer, and 409 697 had a historical diagnosis of cancer. Prostate, breast, colon, and lung cancer were the four most common types of cancer. Patients with cancer were older with more comorbidities. Differences in invasive treatment were noted, 43.9% received percutaneous coronary intervention (PCI) in patients without cancer, whilst only 21.0% of patients with lung cancer received PCI. Lung cancer was associated with the highest in-hospital mortality [odds ratio (OR) 2.71, 95% confidence interval (CI) 2.62-2.80], major adverse cardiovascular and cerebrovascular complications (OR 2.38, 95% CI 2.31-2.45), and stroke (OR 1.91, 95% CI 1.80-2.02), while colon cancer was associated with highest risk of bleeding (OR 2.82, 95% CI 2.68-2.98). Irrespective of the type of cancer, presence of metastasis was associated with worse in-hospital outcomes, and historical cancer did not adversely impact on survival (OR 0.90, 95% CI 0.89-0.91). CONCLUSION: A concomitant cancer diagnosis is associated with a conservative medical management strategy for AMI, and worse clinical outcomes, compared to patients without cancer. Survival and clinical outcomes in the context of AMI vary significantly according to the type of cancer and metastasis status. The management of this high-risk group is challenging and requires a multidisciplinary and patient-centred approach to improve their outcomes.
Assuntos
Infarto do Miocárdio , Neoplasias , Intervenção Coronária Percutânea , Acidente Vascular Cerebral , Mortalidade Hospitalar , Humanos , Masculino , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/terapia , Neoplasias/epidemiologia , Neoplasias/terapia , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/terapia , Resultado do Tratamento , Estados Unidos/epidemiologiaRESUMO
PURPOSE OF REVIEW: The role of renin-angiotensin-aldosterone system (RAAS) inhibitors, notably angiotensin-converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARBs), in the COVID-19 pandemic has not been fully evaluated. With an increasing number of COVID-19 cases worldwide, it is imperative to better understand the impact of RAAS inhibitors in hypertensive COVID patients. PubMed, Embase and the pre-print database Medrxiv were searched, and studies with data on patients on ACEi/ARB with COVID-19 were included. Random effects models were used to estimate the pooled mean difference with 95% confidence interval using Open Meta[Analyst] software. RECENT FINDINGS: A total of 28,872 patients were included in this meta-analysis. The use of any RAAS inhibition for any conditions showed a trend to lower risk of death/critical events (OR 0.671, CI 0.435 to 1.034, p = 0.071). Within the hypertensive cohort, however, there was a significant lower association with deaths (OR 0.664, CI 0.458 to 0.964, p = 0.031) or the combination of death/critical outcomes (OR 0.670, CI 0.495 to 0.908, p = 0.010). There was no significant association of critical/death outcomes within ACEi vs non-ACEi (OR 1.008, CI 0.822 to 1.235, p = 0.941) and ARB vs non-ARB (OR 0.946, CI 0.735 to 1.218, p = 0.668). This is the largest meta-analysis including critical events and mortality data on patients prescribed ACEi/ARB and found evidence of beneficial effects of chronic ACEi/ARB use especially in hypertensive cohort with COVID-19. As such, we would strongly encourage patients to continue with RAAS inhibitor pharmacotherapy during the COVID-19 pandemic.
Assuntos
Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Betacoronavirus , Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , Sistema Renina-Angiotensina/efeitos dos fármacos , COVID-19 , Humanos , Hipertensão/tratamento farmacológico , Pandemias , SARS-CoV-2RESUMO
OBJECTIVES: We sought to answer whether 1-month duration of dual antiplatelet therapy (DAPT) is safe after elective drug-coated balloon only (DCB) angioplasty. BACKGROUND: The duration of DAPT after elective DCB was called into question after the ESC Focused DAPT Update of 2017. Until then, a 1-month duration of DAPT was considered safe by national consensus groups (German, Italian, and Chinese) supported by data from prospective worldwide registries. The ESC Guidelines recommended a 6-month duration of DAPT based on evidence from in-stent restenosis randomized controlled trials only. METHODS: Retrospective, real-world population, single-center analysis conducted from January 1, 2012 to March 31, 2017 in a high-volume, tertiary PCI center. Consecutive patients receiving 1-month duration of DAPT after elective DCB angioplasty were included. We identified a primary composite outcome of cardiac death, myocardial infarction and target lesion revascularization at 6-months. RESULTS: A total of 303 patients (78.5% male) with mean age of 67 ± 12.5 were included. This incorporated 86.1% de novo lesions and 56.5% nonsmall (≥3 mm diameter) coronary arteries treated. There were no reported outcomes of lesion thrombosis, target vessel MI, target lesion revascularization or cardiac death at 6-months. There were two (0.6%) nontarget vessel MIs and one (0.3%) noncardiac death. CONCLUSION: One-month duration of DAPT appears safe after elective DCB-only angioplasty, highlighting this strategy for patients at high-risk of bleeding. These results also show favorable clinical outcomes for de novo coronary artery disease and nonsmall coronary arteries treated with DCB-only angioplasty. A 1-month duration of DAPT appears a safe and attractive option.
Assuntos
Angioplastia Coronária com Balão/instrumentação , Materiais Revestidos Biocompatíveis , Doença da Artéria Coronariana/terapia , Inibidores da Agregação Plaquetária/administração & dosagem , Idoso , Angioplastia Coronária com Balão/efeitos adversos , Angioplastia Coronária com Balão/mortalidade , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Trombose Coronária/etiologia , Trombose Coronária/prevenção & controle , Esquema de Medicação , Terapia Antiplaquetária Dupla , Inglaterra , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/prevenção & controle , Inibidores da Agregação Plaquetária/efeitos adversos , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do TratamentoRESUMO
OBJECTIVE: To report our initial experience with drug coated balloon (DCB) only angioplasty and propose a protocol to achieve this safely. BACKGROUND: There are no articles published in the literature currently regarding the safety of same day discharge in patients treated with DCB-only angioplasty. METHODS: Retrospective review of all our patients treated with DCB-only angioplasty from September 2017 to April 2018 with identification of potential complications relating to same day discharge. RESULTS: A total of 100 consecutive patients who underwent elective DCB-only angioplasty for de novo coronary artery disease and were discharged on the same day as the procedure were included. In 99% no cardiac symptoms relating to the procedure requiring urgent hospitalization or urgent investigations were identified. One patient was readmitted the next day requiring stenting of the previously treated lesion. Our 30-day mortality was zero. Some 97 hospital bed days were saved with 100 patients treated. CONCLUSION: Elective day-case DCB-only angioplasty according to our local protocol is safe and cost-effective and should be considered for the majority of the patients.
Assuntos
Angioplastia Coronária com Balão/instrumentação , Cateteres Cardíacos , Materiais Revestidos Biocompatíveis , Doença da Artéria Coronariana/terapia , Tempo de Internação , Alta do Paciente , Idoso , Angioplastia Coronária com Balão/efeitos adversos , Protocolos Clínicos , Doença da Artéria Coronariana/diagnóstico por imagem , Inglaterra , Desenho de Equipamento , Feminino , Hospitais com Alto Volume de Atendimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do TratamentoRESUMO
PURPOSE: Interpreting a twelvelead electrocardiogram (ECG) is a basic, albeit essential skill for most healthcare professionals to attain. Despite its importance, evidence suggests that the competency of healthcare professionals to interpret ECGs can be improved. We evaluated the effectiveness of a national interactive workshop designed to improve ECG interpretation in the UK medical student cohort. METHODS: UK medical students who attended a national workshop were asked to complete a pre- and post- workshop test which comprised of 20 ECGs which showed a variety of pathologies relating to conduction disturbances, tachycardia and acute coronary syndromes. The workshop was interactive and consisted of 6 h of ECG tutorials, divided into hourly sessions which covered all key topics such as 'basic electrophysiology' and 'electro-conduction problems'. Pre- and post-workshop test scores were compared by difference in means using the paired two-tailed t-test. RESULTS: A total of 145 participants completed the pre-test and of those 44 completed both the pre and post-test. The mean pre-test and post-test scores were 9.7/20 questions (48.9%) and 11.2/20 questions (56.2%) respectively, with a mean improvement of 1.5/20 (7.3%) from pre- to post-test (+7.3%, 95% CI: +1.8 to +12.8%, p = 0.01). CONCLUSION: A national ECG workshop which emphasizes activity-based learning may be effective in improving the competency of medical students to interpret ECGs. Further exploration with multi-center controlled studies involving a diverse cohort of students and analyses to determine their cost-effectiveness is warranted.
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Estudantes de Medicina , Competência Clínica , Eletrocardiografia , Humanos , Ensino , Reino UnidoRESUMO
PURPOSE OF REVIEW: Chronic total occlusion (CTO) of the coronary arteries is a significant clinical problem and has traditionally been treated by medical therapy or coronary artery bypass grafting. Recent studies have examined percutaneous coronary intervention (PCI) as an alternative option. RECENT FINDINGS: This systematic review and meta-analysis compared medical therapy to PCI for treating CTOs. PubMed and Embase were searched from their inception to March 2019 for studies that compared medical therapy and PCI for clinical outcomes in patients with CTOs. Quality of the included studies was assessed by Newcastle-Ottawa scale. The results were pooled by DerSimonian and Laird random- or fixed-effect models as appropriate. Heterogeneity between studies and publication bias was evaluated by I2 index and Egger's regression, respectively. Of the 703 entries screened, 17 studies were included in the final analysis. This comprised 11,493 participants. Compared to PCI, medical therapy including randomized and observational studies was significantly associated with higher risk of all-cause mortality (risk ratio (RR) 1.99, 95% CI 1.38-2.86), cardiac mortality (RR 2.36 (1.97-2.84)), and major adverse cardiac event (RR 1.25 (1.03-1.51)). However, no difference in the rate of myocardial infarction and repeat revascularization procedures was observed between the two groups. Univariate meta-regression demonstrated multiple covariates as independent moderating factors for myocardial infarction and repeat revascularization but not cardiac death and all-cause mortality. However, when only randomized studies were included, there was no difference in overall mortality or cardiac death. In CTO, when considering randomized and observational studies, medical therapy might be associated with a higher risk of mortality and myocardial infarction compared to PCI treatment.
Assuntos
Oclusão Coronária/terapia , Vasos Coronários/cirurgia , Fibrinolíticos/uso terapêutico , Intervenção Coronária Percutânea/métodos , Terapia Trombolítica/métodos , Doença Crônica , Angiografia Coronária , Oclusão Coronária/diagnóstico , Vasos Coronários/diagnóstico por imagem , HumanosRESUMO
BACKGROUND: Current guidelines only recommend the use of an implantable cardioverter defibrillator in patients with dilated cardiomyopathy for the primary prevention of sudden cardiac death (SCD) in those with a left ventricular ejection fraction (LVEF) <35%. However, registries of out-of-hospital cardiac arrests demonstrate that 70% to 80% of such patients have an LVEF >35%. Patients with an LVEF >35% also have low competing risks of death from nonsudden causes. Therefore, those at high risk of SCD may gain longevity from successful implantable cardioverter defibrillator therapy. We investigated whether late gadolinium enhancement (LGE) cardiovascular magnetic resonance identified patients with dilated cardiomyopathy without severe LV systolic dysfunction at high risk of SCD. METHODS: We prospectively investigated the association between midwall LGE and the prespecified primary composite outcome of SCD or aborted SCD among consecutive referrals with dilated cardiomyopathy and an LVEF ≥40% to our center between January 2000 and December 2011 who did not have a preexisting indication for implantable cardioverter defibrillator implantation. RESULTS: Of 399 patients (145 women, median age 50 years, median LVEF 50%, 25.3% with LGE) followed for a median of 4.6 years, 18 of 101 (17.8%) patients with LGE reached the prespecified end point, compared with 7 of 298 (2.3%) without (hazard ratio [HR], 9.2; 95% confidence interval [CI], 3.9-21.8; P<0.0001). Nine patients (8.9%) with LGE compared with 6 (2.0%) without (HR, 4.9; 95% CI, 1.8-13.5; P=0.002) died suddenly, whereas 10 patients (9.9%) with LGE compared with 1 patient (0.3%) without (HR, 34.8; 95% CI, 4.6-266.6; P<0.001) had aborted SCD. After adjustment, LGE predicted the composite end point (HR, 9.3; 95% CI, 3.9-22.3; P<0.0001), SCD (HR, 4.8; 95% CI, 1.7-13.8; P=0.003), and aborted SCD (HR, 35.9; 95% CI, 4.8-271.4; P<0.001). Estimated HRs for the primary end point for patients with an LGE extent of 0% to 2.5%, 2.5% to 5%, and >5% compared with those without LGE were 10.6 (95% CI, 3.9-29.4), 4.9 (95% CI, 1.3-18.9), and 11.8 (95% CI, 4.3-32.3), respectively. CONCLUSIONS: Midwall LGE identifies a group of patients with dilated cardiomyopathy and an LVEF ≥40% at increased risk of SCD and low risk of nonsudden death who may benefit from implantable cardioverter defibrillator implantation. CLINICAL TRIAL REGISTRATION: URL: http://clinicaltrials.gov. Unique identifier: NCT00930735.
Assuntos
Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/mortalidade , Morte Súbita Cardíaca/patologia , Gadolínio , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/mortalidade , Adulto , Idoso , Cardiomiopatia Dilatada/epidemiologia , Endotélio Vascular/diagnóstico por imagem , Feminino , Seguimentos , Gadolínio/administração & dosagem , Humanos , Imagem Cinética por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Volume Sistólico/fisiologia , Disfunção Ventricular Esquerda/epidemiologiaRESUMO
Mapping of the longitudinal relaxation time (T 1) and extracellular volume (ECV) offers a means of identifying pathological changes in myocardial tissue, including diffuse changes that may be invisible to existing T 1-weighted methods. This technique has recently shown strong clinical utility for pathologies such as Anderson-Fabry disease and amyloidosis and has generated clinical interest as a possible means of detecting small changes in diffuse fibrosis; however, scatter in T 1 and ECV estimates offers challenges for detecting these changes, and bias limits comparisons between sites and vendors. There are several technical and physiological pitfalls that influence the accuracy (bias) and precision (repeatability) of T 1 and ECV mapping methods. The goal of this review is to describe the most significant of these, and detail current solutions, in order to aid scientists and clinicians to maximise the utility of T 1 mapping in their clinical or research setting. A detailed summary of technical and physiological factors, issues relating to contrast agents, and specific disease-related issues is provided, along with some considerations on the future directions of the field.
Assuntos
Técnicas de Imagem Cardíaca/métodos , Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Suspensão da Respiração , Técnicas de Imagem Cardíaca/estatística & dados numéricos , Meios de Contraste , Circulação Coronária , Espaço Extracelular/diagnóstico por imagem , Feminino , Fibrose , Gadolínio , Cardiopatias/diagnóstico por imagem , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Masculino , Movimento (Física) , Miocárdio/patologia , Razão Sinal-RuídoRESUMO
OBJECTIVES: Our objectives involved identifying whether repeated averaging in basal and mid left ventricular myocardial levels improves precision and correlation with collagen volume fraction for 11 heartbeat MOLLI T 1 mapping versus assessment at a single ventricular level. MATERIALS AND METHODS: For assessment of T 1 mapping precision, a cohort of 15 healthy volunteers underwent two CMR scans on separate days using an 11 heartbeat MOLLI with a 5(3)3 beat scheme to measure native T 1 and a 4(1)3(1)2 beat post-contrast scheme to measure post-contrast T 1, allowing calculation of partition coefficient and ECV. To assess correlation of T 1 mapping with collagen volume fraction, a separate cohort of ten aortic stenosis patients scheduled to undergo surgery underwent one CMR scan with this 11 heartbeat MOLLI scheme, followed by intraoperative tru-cut myocardial biopsy. Six models of myocardial diffuse fibrosis assessment were established with incremental inclusion of imaging by averaging of the basal and mid-myocardial left ventricular levels, and each model was assessed for precision and correlation with collagen volume fraction. RESULTS: A model using 11 heart beat MOLLI imaging of two basal and two mid ventricular level averaged T 1 maps provided improved precision (Intraclass correlation 0.93 vs 0.84) and correlation with histology (R 2 = 0.83 vs 0.36) for diffuse fibrosis compared to a single mid-ventricular level alone. ECV was more precise and correlated better than native T 1 mapping. CONCLUSION: T 1 mapping sequences with repeated averaging could be considered for applications of 11 heartbeat MOLLI, especially when small changes in native T 1/ECV might affect clinical management.
Assuntos
Técnicas de Imagem Cardíaca/métodos , Colágeno/metabolismo , Imageamento por Ressonância Magnética/métodos , Miocárdio/metabolismo , Miocárdio/patologia , Adulto , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/metabolismo , Estenose da Valva Aórtica/patologia , Biópsia , Técnicas de Imagem Cardíaca/estatística & dados numéricos , Estudos de Coortes , Meios de Contraste , Feminino , Fibrose , Gadolínio , Voluntários Saudáveis , Frequência Cardíaca , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Masculino , Modelos Cardiovasculares , Modelos Estatísticos , Reprodutibilidade dos TestesRESUMO
BACKGROUND AND OBJECTIVES: Congenital long QT syndrome (LQTS) predisposes affected individuals to ventricular tachycardia/fibrillation (VF/VF), potentially resulting in sudden cardiac death. The Tpeak-Tend interval and the Tpeak-Tend/QT ratio, electrocardiographic markers of dispersion of ventricular repolarization, were proposed for risk stratification but their predictive values in LQTS have been controversial. A systematic review and meta-analysis was conducted to examine the value of Tpeak-Tend intervals and Tpeak-Tend/QT ratios in predicting arrhythmic and mortality outcomes in congenital LQTS. METHOD: PubMed and Embase databases were searched until 9th May 2017, identifying 199 studies. RESULTS: Five studies on long QT syndrome were included in the final meta-analysis. Tpeak-Tend intervals were longer (mean difference [MD]: 13ms, standard error [SE]: 4ms, P=0.002; I2=34%) in congenital LQTS patients with adverse events [syncope, ventricular arrhythmias or sudden cardiac death] compared to LQTS patients without such events. By contrast, Tpeak-Tend/QT ratios were not significantly different between the two groups (MD: 0.02, SE: 0.02, P=0.26; I2=0%). CONCLUSION: This meta-analysis showed that Tpeak-Tend interval is significant higher in individuals who are at elevated risk of adverse events in congenital LQTS, offering incremental value for risk stratification.
Assuntos
Eletrocardiografia , Síndrome do QT Longo/congênito , Síndrome do QT Longo/fisiopatologia , Medição de Risco , Humanos , Fatores de RiscoAssuntos
Cardiomiopatias/diagnóstico por imagem , Insuficiência da Valva Mitral/diagnóstico por imagem , Sarcoidose/complicações , Idoso de 80 Anos ou mais , Cardiomiopatias/complicações , Coração/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Sarcoidose/diagnóstico por imagemRESUMO
BACKGROUND: Magnetic resonance imaging (MRI) phantoms are routinely used for quality assurance in MRI centres; however their long term stability for verification of myocardial T1/ extracellular volume fraction (ECV) mapping has never been investigated. METHODS: Nickel-chloride agarose gel phantoms were formulated in a reproducible laboratory procedure to mimic blood and myocardial T1 and T2 values, native and late after Gadolinium administration as used in T1/ECV mapping. The phantoms were imaged weekly with an 11 heart beat MOLLI sequence for T1 and long TR spin-echo sequences for T2, in a carefully controlled reproducible manner for 12 months. RESULTS: There were only small relative changes seen in all the native and post gadolinium T1 values (up to 9.0 % maximal relative change in T1 values) or phantom ECV (up to 8.3 % maximal relative change of ECV, up to 2.2 % maximal absolute change in ECV) during this period. All native and post gadolinium T2 values remained stable over time with <2 % change. Temperature sensitivity testing showed MOLLI T1 values in the long T1 phantoms increasing by 23.9 ms per degree increase and short T1 phantoms increasing by 0.3 ms per degree increase. There was a small absolute increase in ECV of 0.069 % (~0.22 % relative increase in ECV) per degree increase. Variation in heart rate testing showed a 0.13 % absolute increase in ECV (~0.45 % relative increase in ECV) per 10 heart rate increase. CONCLUSIONS: These are the first phantoms reported in the literature modeling T1 and T2 values for blood and myocardium specifically for the T1mapping/ECV mapping application, with stability tested rigorously over a 12 month period. This work has significant implications for the utility of such phantoms in improving the accuracy of serial scans for myocardial tissue characterisation by T1 mapping methods and in multicentre work.
RESUMO
Aims: Stroke is the most debilitating outcome of atrial fibrillation (AF). The use of implantable loop recorders increases the detection of AF episodes among patients with embolic stroke of undetermined source. The significance of device-detected AF, or subclinical AF, is unknown. This study aimed to compare the incidence of AF detected by implantable loop recorder in patients with and without embolic stroke of undetermined source. Methods and results: We retrospectively studied all patients without known AF who were referred to our institution for implantable loop recorder implantation following embolic stroke of undetermined source, syncope, or palpitations from March 2009 to November 2019. The primary endpoint was any detection of AF or atrial flutter by implantable loop recorder. Seven hundred and fifty patients were included and followed up for a mean duration of 731 days (SD 443). An implantable loop recorder was implanted following embolic stroke of undetermined source in 323 and for assessment of syncope, palpitations, or another reason in 427 patients. The incidence of AF was significantly (P < 0.001) higher among patients with embolic stroke of undetermined source compared with the non-embolic stroke of undetermined source group; 48.6% vs. 13.8% (for any duration of AF) and 32.2% vs. 12.4% (for AF lasting ≥30â s) both P < 0.001. Kaplan-Meier analysis showed significantly higher incidence of AF for incremental durations of AF up to >5.5â h, but not >24â h. This was driven by longest AF durations of <6â min and between 5.5â h and 24â h, suggesting a bimodal distribution. In a multivariable Cox regression analysis, embolic stroke of undetermined source independently conferred an almost 5-fold increase in the hazard for any duration of AF. Conclusion: The incidence of AF is significantly higher amongst embolic stroke of undetermined source vs. non-embolic stroke of undetermined source patients monitored constantly by an implantable loop recorder. A high number of embolic stroke of undetermined source survivors have short-duration AF episodes. Further work is needed to determine the optimal treatment strategy of these AF episodes in embolic stroke of undetermined source.