Severity Of Left Ventricular Function Research Articles

New-Onset Ventricular Arrhythmias in Patients with Left Ventricular Dysfunction after Coronary Surgery: Incidence, Risk Factors, and Prognosis.

The incidence, risk factors, and long-term prognosis of new-onset ventricular tachycardia (VT) and ventricular fibrillation (VF) after coronary artery bypass graft surgery (CABG) in patients with impaired left ventricular function have not been thoroughly examined.Methods: This study enrolled 612 consecutive patients with impaired left ventricular function (ejection fraction <50%) undergoing CABG at a single institution between March, 1996, and September, 2015. Outcomes were analyzed and compared, including in-hospital mortality and long-term survival. After a propensity-score, matching was performed to adjust for differences between the two cohorts. Factors significantly associated with VT/VF were also investigated using multivariate logistic regression. Of the 600 patients included in the analyses, 92 (15.3%; 95% confidence interval [CI] 12.5-18.3%) had new-onset VT/VF postoperatively. Before propensity matching, patients with postoperative VT/VF were more likely to have renal failure, intra-aortic balloon pump support, lower preoperative ejection fraction (EF), and a larger left ventricle than those without VT/VF. Multivariate regression identified three preoperative risk factors and one protective factor that were independently associated with new-onset VT/VF: previous renal failure (odds ratio [OR] 4.42, P = .02), left ventricular end-diastolic dimension enlargement (OR 1.83, P = .03), ejection fraction (OR 1.88, P = .02 for EF ≥30 and <40% versus ≥40% and <50%; OR 5.46, P = .00 for EF <30% versus ≥40% and <50%), and preoperative β-blockers (OR 0.58, P = .03). The median follow-up time was 46.6 months. In the propensity-matched cohorts, survival for patients who had in-hospital VT/VF was lower than that of the non-VT/VF group (89.9% versus 97.6%; P < .05). This study shows a high incidence of new-onset VT/VF after CABG in patients with impaired left ventricular function. The early and long-term survival rates were significantly lower in the VT/VF group. Preoperative renal failure, left ventricular end-systolic dimension enlargement, and the severity of left ventricular function were independently associated with the development of new-onset VT/VF after CABG surgery. Preoperative use of beta-blocker was proved to be protective in reducing both VT/VF incidence and in-hospital mortality in CABG patients with impaired left ventricular function following CABG. When considering these data, a prescription of beta-blockers is prognostically indicated to CABG patients, especially those with new-onset VT/VF postoperatively.

Health-e-Child Project: Mechanical Dyssynchrony in Children with Dilated Cardiomyopathy

Left ventricular mechanical dyssynchrony has been poorly studied in the pediatric population with dilated cardiomyopathy. We investigated the degree of dyssynchrony in children with dilated cardiomyopathy using tissue Doppler imaging and speckle tracking strain. Twenty-five children with dilated cardiomyopathy were compared with healthy subjects. Left ventricular mechanical dyssynchrony was assessed by speckle tracking strain and tissue Doppler imaging. Both radial and longitudinal dyssynchrony were analyzed. Left ventricular end-diastolic diameter was measured to assess the relation between dyssynchrony and ventricular function and remodeling. Radial and longitudinal dyssynchrony parameters were significantly higher in the dilated cardiomyopathy group and correlated with Z-score left ventricular end-diastolic diameter. A logarithmic correlation between left ventricular ejection fraction and left ventricular end-diastolic diameter parameters was found. In children with dilated cardiomyopathy, tissue Doppler imaging and speckle tracking strain allowed the detection of dyssynchrony, which correlates with the severity of left ventricular function.

Correlation of the myocardial performance index with plasma B-type natriuretic peptide levels in patients with mitral regurgitation

The Myocardial performance index (MPI) is an echocardiographic index of combined systolic and diastolic function, calculated as isovolumetric relaxation time plus isovolumetric contraction time divided by ejection time. The aim of this study was to define the correlation of the MPI with plasma B-type natriuretic peptide (BNP) levels and echocardiographic parameters in patients with chronic mitral regurgitation (MR). About 33 patients with at least moderate MR of organic etiology were enrolled to the study. All patients undergone complete 2D and Doppler echocardiography. Plasma BNP levels were studied. BNP levels in NYHA classes I-III were 9.3 +/- 2.2 pg/ml, 61.3 +/- 12.2 pg/ml, and 199.6 +/- 55.2 pg/ml, respectively (I vs. II P < 0.001, I vs. III P < 0.001 and II vs. III P = 0.004). Myocardial performance index were 0.42 +/- 0.02, 0.49 +/- 0.02, and 0.52 +/- 0.03 in MR patients with NYHA I-III, respectively. MPI was significantly higher in patients with NYHA class III compared to NYHA I (P = 0.001) and NYHA II (P = 0.005). There were no correlations between MPI and left atrial diameter, MR jet area, MR index and systolic pulmonary artery pressure whereas left ventricle (LV) end-systolic volume (r = 0.38), LV end-diastolic volume (LVDV) (r = 0.40), LV ejection fraction (r = -0.59), NYHA class (r = 0.51) and plasma BNP levels (r = 0.67) were strongly correlated. Only independent variable affecting MPI was plasma BNP level (odds ratio [CI]: 2.18[0.002-0.098], P = 0.041). MPI is a powerful index in assessing the severity of left ventricular function and symptom severity in patients with MR. Plasma BNP is an independent predictor of MPI where both parameters assess combined systolic and diastolic LV function, effectively.

Serial changes and prognostic implications of a Doppler-derived index of combined left ventricular systolic and diastolic myocardial performance in acute myocardial infarction

The purpose of this study was to investigate the serial changes and prognostic value of a nongeometric Doppler-derived index of myocardial function that combines systolic and diastolic time intervals of the left ventricle in acute myocardial infarction (AMI). The Doppler index was measured in 60 consecutive patients with AMI and in 30 patients admitted to hospital with suspected but disproved AMI who served as controls. The patients were studied at days 1, 5, 90, and 360 after arrival in the coronary care unit. The index was defined as the sum of isovolumetric contraction time, and isovolumetric relaxation time divided by ejection time was measured from mitral inflow and left ventricular outflow Doppler velocity profiles. The index was significantly higher in patients with AMI than in control subjects at days 1 and 360 (day 1, 0.58 ± 0.09 vs 0.41 ± 0.08, p <0.0001; day 360, 0.50 ± 0.09 vs 0.39 ± 0.07, p <0.01, respectively). The index decreased significantly in patients with AMI during follow-up (p <0.01). The index was significantly higher in patients who developed congestive heart failure or died compared with survivors who were free of congestive heart failure (day 1, 0.63 ± 0.10 vs 0.53 ± 0.10, p <0.01; day 360, 0.56 ± 0.08 vs 0.48 ± 0.10, p <0.01, respectively). During 20.2 ± 8.5 months’ follow-up, 10 patients died of cardiac causes and 13 developed congestive heart failure. Univariate analyses demonstrated that the Doppler index ≥0.60 (chi-square 8.3, p <0.0001), deceleration time ≤140 ms (chi-square 8.5, p <0.0001), ejection fraction ≤0.40% (chi-square 3.3, p <0.005), anterior wall AMI (chi-square 3.2, p <0.01), and age (chi-square 1.06/year increase, p <0.01) were significant predictors of outcome. Multivariate stepwise analysis showed that the index ≤0.60 (chi-square 3.4, p <0.05), deceleration time ≤140 ms (chi-square 4.2, p <0.02), and age (chi-square 1.06/year increase, p <0.02) were independent predictors of outcome. The Doppler index reflects severity of left ventricular function and has incremental prognostic value in patients with AMI.