RESUMO
Electrocardiographic (ECG) abnormalities are frequently identified in Chronic Chagas cardiomyopathy (CCC) patients and advanced abnormalities are related to a worse prognosis. Cardiac Magnetic Resonance (CMR) can precisely assess ventricular systolic dysfunction and quantify myocardial fibrosis (MF), both identified as prognostic factors. We sought to investigate if ECG abnormalities in CCC patients were associated with more severe myocardial involvement as evaluated by CMR. METHODS: CCC patients with 12lead ECG and CMR closely obtained were included. ECG analysis evaluated rhythm, presence, and type of intraventricular conduction disturbances (IVCD) and, ventricular premature beats (VPB). CMR short-axis cine and late gadolinium enhancement images were evaluated to obtain left and right ventricular ejection fractions and MF mass, respectively. Statistical significance was set in 5%. RESULTS: 194 CCC patients (98 women, 56 ± 14 years) were evaluated, and no IVCD was detected in 71. The most common IVCD was the association of right bundle branch block and left anterior fascicular block (RBBB+LAFB) in 58 patients, followed by isolated RBBB in 34, isolated LAFB in 17, and left bundle branch block (LBBB) in 14 patients. Of patients with no IVCD, 63% had MF and the burden of fibrosis (no IVCD - 7.4 ± 8.6%; RBBB - 6.6 ± 6.5%; p = 1.00), as well as left ventricular ejection fraction (LVEF) (no IVCD - 52 ± 14%; RBBB - 55 ± 10%; p = 1.00) were similar to patients with isolated RBBB. Left conduction system impairment was associated with lower LVEF (LAFB - 39 ± 15%; RBBB+LAFB- 41 ± 15%; and LBBB - 35 ± 15%; p < 0.001) and more MF (RBBB+LAFB - 12.2 ± 10.4%; LBBB - 10.6 ± 7.5%; and LAFB - 12.0 ± 7.0%; p < 0.001). The univariable model showed that the presence of MF was related to RBBB+LAFB (OR 5.0; p = 0.001) and VPB (OR 6.3; p = 0.014). After adjustment for age, gender, and different risk factors in a multivariable model, the same findings were still significantly related to CMR myocardial fibrosis (RBBB+LAFB OR 5.0; p = 0.002 / VPB OR 6.9; p = 0.015). CONCLUSIONS: ECG without IVCD does not exclude serious cardiac abnormalities in CCC, and isolated RBBB seems to have a benign course. The presence of VPB and left branch conduction impairment, especially LAFB associated with RBBB, indicate a more severe cardiac involvement.
Assuntos
Cardiomiopatias , Cardiomiopatia Chagásica , Doença de Chagas , Disfunção Ventricular Esquerda , Arritmias Cardíacas/complicações , Bloqueio de Ramo , Cardiomiopatias/complicações , Cardiomiopatia Chagásica/complicações , Cardiomiopatia Chagásica/diagnóstico por imagem , Doença de Chagas/complicações , Cicatriz/complicações , Meios de Contraste , Eletrocardiografia , Feminino , Gadolínio , Humanos , Imageamento por Ressonância Magnética , Volume Sistólico , Disfunção Ventricular Esquerda/complicações , Disfunção Ventricular Esquerda/etiologia , Função Ventricular EsquerdaRESUMO
OBJECTIVES: This study aimed to determine feasibility, reference intervals, and reproducibility of left ventricular ejection fraction (LVEF) and speckle-tracking echocardiography (STE) in adult Syrian hamsters. BACKGROUND: Syrian hamster is an experimental model for several heart diseases. Echocardiography allows the evaluation of structure and function with bidimensional conventional techniques and STE. However, there is no data regarding reference values for bidimensional LVEF and myocardial strain in hamsters. METHODS: A total of 135 female Syrian hamsters were anesthetized and studied with a small animal dedicated echocardiography system. Echocardiography measurements were obtained from M-mode and B-mode images. Feasibility and 95% reference intervals were obtained for LVEF using three different approaches: LVEF_Teichholz (from M-mode linear measurements), LVEF_BMode (from area-length method), and LVEF_ STE (from strain), and for global longitudinal (GLS), circumferential (GCS), and radial (GRS) endocardial strain. Reproducibility was assessed as intra-class correlation coefficients. RESULTS: Feasibility of LVEF and endocardial strain was high (95% in FEVE_Teichholz, 93% in the LVEF_BMode, 84% in the LVEF_STE, 84% from PSLAX, and 80% from PSSAX). Values of LVEF_Teichholz were significantly higher than values of LVEF_BMode, and LVEF_STE-derived methods (59.0 ± 5.8, 53.8 ± 4.7, 46.3 ± 5.7, p < 0.0001). The 95% reference intervals for GLS, GCS, and GRS were respectively -13.6(-7.5;-20.4)%, -20.5 ± 3.1%, and + 34,7 ± 7.0%. Intra-class correlation coefficients were 0.49 - 0.91 for LVEF measurements, 0.73 - 0.92 for STE, with better results for LVEF_Teichholz and GLS. CONCLUSIONS: Evaluation of LVEF by several methods and STE parameters is feasible in hamsters. Reference intervals for LVEF and STE obtained for this experimental animal model can be applied at future research.
Assuntos
Ecocardiografia Tridimensional , Ecocardiografia , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Animais , Cricetinae , Ecocardiografia/métodos , Ecocardiografia Tridimensional/métodos , Estudos de Viabilidade , Ventrículos do Coração/fisiopatologia , Interpretação de Imagem Assistida por Computador/métodos , Valores de Referência , Disfunção Ventricular Esquerda/fisiopatologiaRESUMO
BACKGROUND: Lower pulmonary artery acceleration time (PAcT) is correlated with higher pulmonary artery pressure. The aim of this study was to test the hypothesis that PAcT measured in young adulthood would be associated with future cardiovascular outcomes. METHODS: In the Coronary Artery Risk Development in Young Adults year 5 examination (1990-1991), PAcT was measured as the time interval from onset to peak flow velocity at the pulmonary valve annulus on Doppler echocardiography. The primary outcome was a composite of fatal or nonfatal cardiovascular disease events: myocardial infarction, non-myocardial infarction acute coronary syndrome, coronary revascularization, congestive heart failure, stroke, transient ischemic attack, carotid artery disease, and peripheral arterial disease. RESULTS: PAcT was obtained in 4,171 participants (mean age, 30 ± 4 years, 55% women, 51% white). PAcT groups obtained using linear spline methodology were as follows: group I, PAcT ≥ 196 msec (n = 122); group II, PAcT < 196 and ≥115 msec (n = 3,195); and group III, PAcT < 115 msec (n = 854). During follow-up (median, 24.9 years), the primary outcome occurred in 216 participants (5.2%); 66 of 854 (7.7%) of those with PAcT < 115 msec, 149 of 3,195 (4.7%) of those with intermediate PAcT level, and one of 122 (0.8%) of those with PAcT ≥ 196 msec. In a fully adjusted model, the lowest and intermediate PAcT groups had hazard ratios of 8.3 (95% CI, 1.1-62.1; P = .04) and 6.8 (95% CI, 0.9-50.5; P = .06), respectively, in comparison with the highest PAcT group. CONCLUSIONS: PAcT is useful for better identifying young adults at higher risk for cardiovascular events, who may benefit from a strict control of modifiable cardiovascular risk factors.
Assuntos
Doenças Cardiovasculares/fisiopatologia , Vasos Coronários/fisiopatologia , Ecocardiografia Doppler/métodos , Artéria Pulmonar/fisiopatologia , Adolescente , Adulto , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/fisiopatologia , Vasos Coronários/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Incidência , Masculino , Valor Preditivo dos Testes , Estudos Prospectivos , Artéria Pulmonar/diagnóstico por imagem , Medição de Risco/métodos , Fatores de Risco , Estados Unidos/epidemiologia , Adulto JovemRESUMO
BACKGROUND: Patients with chronic Chagas cardiomyopathy (CCC) have pronounced myocardial fibrosis, which may predispose to sudden cardiac death, despite well-preserved global left ventricular (LV) systolic function. Cardiac magnetic resonance can assess myocardial fibrosis by late gadolinium enhancement (LGE) sequences. OBJECTIVES: This prospective study evaluated if the presence of scar by LGE predicted hard adverse outcomes in a cohort of patients with CCC. METHODS: A prospective cohort of 140 patients with CCC (52.1% female; median age 57 years [interquartile range: 45 to 67 years]) were included. Cardiac magnetic resonance cine and LGE imaging were performed at enrollment with a 1.5-T scanner. The primary endpoint was the combination of cardiovascular death and sustained ventricular tachycardia. The secondary endpoint was the combination of cardiovascular death, sustained ventricular tachycardia, or cardiovascular hospitalization during follow-up. RESULTS: After a median of 34 months (interquartile range: 24 to 49 months) of follow-up, 11 cardiovascular deaths, 3 episodes of sustained ventricular tachycardia, and 20 cardiovascular hospitalizations were recorded. LGE scar was present in 71.4% of the patients, with the lateral, inferolateral, and inferior walls most commonly affected. Patients with positive LGE had lower LV ejection fraction and higher LV end-diastolic volume and LV mass than patients without LGE. No difference in other cardiovascular risk factors was noted. Patients with scar had higher event rates compared with those without scar for the primary (p = 0.043) and the secondary (p = 0.016) endpoint. In multivariable analysis, age and LGE area were related to primary outcome; age and lower LV ejection fraction were related to the secondary outcome. The pattern of LGE myocardial fibrosis was transmural, focal, or diffuse scar in approximately one-third of patients with positive LGE, and no pattern was specifically related to outcomes. CONCLUSIONS: In patients with CCC, presence of scar by LGE is common and is strongly associated with major adverse outcomes.
Assuntos
Cardiomiopatia Chagásica/diagnóstico por imagem , Cardiomiopatia Chagásica/mortalidade , Cicatriz/diagnóstico por imagem , Cicatriz/mortalidade , Ventrículos do Coração/diagnóstico por imagem , Adulto , Idoso , Doença Crônica , Estudos de Coortes , Eletrocardiografia/tendências , Feminino , Seguimentos , Humanos , Imagem Cinética por Ressonância Magnética/tendências , Masculino , Pessoa de Meia-Idade , Mortalidade/tendências , Prognóstico , Estudos ProspectivosRESUMO
Right ventricle (RV) is considered a neglected chamber in cardiology and knowledge about its role in cardiac function was mostly focused on ventricular interdependence. However, progress on the understanding of myocardium diseases primarily involving the RV led to a better comprehension of its role in health and disease. In Chagas disease (CD), there is direct evidence from both basic and clinical research of profound structural RV abnormalities. However, clinical detection of these abnormalities is hindered by technical limitations of imaging diagnostic tools. Echocardiography has been a widespread and low-cost option for the study of patients with CD but, when applied to the RV assessment, faces difficulties such as the absence of a geometrical shape to represent this cavity. More recently, the technique has evolved to a focused guided RV imaging and myocardial deformation analysis. Also, cardiac magnetic resonance (CMR) has been introduced as a gold standard method to evaluate RV cavity volumes. CMR advantages include precise quantitative analyses of both LV and RV volumes and its ability to perform myocardium tissue characterization to identify areas of scar and edema. Evolution of these cardiac diagnostic techniques opened a new path to explore the pathophysiology of RV dysfunction in CD.
Assuntos
Cardiomiopatia Chagásica/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Ecocardiografia , Humanos , Imagem Cinética por Ressonância MagnéticaRESUMO
BACKGROUND: Strain and strain rate are sensitive markers of left ventricular (LV) myocardial function. The aim of this study was to assess reference ranges and regional patterns of LV strain and strain rate using two-dimensional speckle-tracking echocardiography in a large population of black and white subjects. METHODS: This study involved a retrospective review of prospectively collected images in 557 participants in the Coronary Artery Risk Development in Young Adults study who remained healthy at the year 25 examination. LV deformation parameters were measured in apical four-chamber, apical two-chamber, and parasternal short-axis views in 509, 391, and 521 subjects, respectively. RESULTS: Patients' mean age was 49.6 ± 3.6 years, 61.6% were women, and 69.5% were white. White women showed the highest LV systolic and diastolic deformation values, reflected by a more negative reference range for apical four-chamber longitudinal strain (-16.4%; 95% prediction interval [PI], -20.8% to -12.0%) and a higher positive reference range for early diastolic strain rate (0.93 1/sec; 95% PI, 0.41 to 1.46 1/sec), respectively. The lowest LV systolic and diastolic deformation values were found in black men, with apical four-chamber longitudinal strain (14.7%; 95% PI, -19.1% to -10.3%) and early diastolic strain rate (0.79 1/sec; 95% PI, 0.42 to 1.16 1/sec). Absolute strain increased from the epicardium toward the endocardium. A base-to-apex gradient of longitudinal strain toward the apex was exhibited in inferior and inferoseptal regions and, in contrast, in the opposite direction in anterior and anterolateral walls. Sex had the strongest influence on LV deformation variability. CONCLUSIONS: Strain and strain rate reference values were sex and race related. White women showed the highest reference ranges for LV deformation, while the lowest values were found in black men. Significant layer- and level-specific patterns in regional LV deformation were identified.