Dyssynchrony and the risk of ventricular arrhythmias

OBJECTIVES: The aim of our study was to evaluate the relationship between left ventricular (LV) dyssynchrony and the risk of ventricular tachycardia (VT) or ventricular fibrillation (VF) in patients enrolled in the MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy) trial. BACKGROUND: Intraventricular mechanical dyssynchrony might be an important factor in ventricular arrhythmogenesis by enhancing electrical heterogeneity in heart failure patients. The effects of dyssynchrony have not yet been evaluated in a large cohort of implantable cardioverter-defibrillator (ICD) and cardiac resynchronization therapy with defibrillator (CRT-D) patients. METHODS: LV dyssynchrony was measured at baseline and at 12-months by speckle-tracking echocardiography, defined as the standard deviation of time to peak systolic strain in 12 LV myocardial segments. The endpoint was the first VT/VF/death or VT/VF. LV dyssynchrony was evaluated in 764 left bundle branch block (LBBB) patients and in 312 non-LBBB patients. RESULTS: Baseline LV dyssynchrony was not predictive of VT/VF/death or VT/VF in LBBB or non-LBBB patients in either treatment arm. In CRT-D patients with LBBB, improvement in LV dyssynchrony over a year was associated with significantly lower incidence of VT/VF/death (p < 0.001) and VT/VF (p < 0.001) compared to ICD patients and to CRT-D patients with unchanged or worsening dyssynchrony. Among LBBB patients, 15% decrease in LV dyssynchrony was associated with lower risk of VT/VF/death (hazard ratio: 0.49, 95% confidence interval: 0.24 to 0.99, p = 0.049) and VT/VF (hazard ratio: 0.30, 95% confidence interval: 0.12 to 0.77, p = 0.009) as compared to ICD patients. Patients without LBBB receiving CRT-D did not show reduction in VT/VF/death or in VT/VF in relation to improving dyssynchrony when evaluating cumulative event rates or risk of events. CONCLUSIONS: Baseline LV dyssynchrony did not predict VT/VF/death or VT/VF in mild heart failure patients with or without LBBB. CRT-induced improvement of LV dyssynchrony was associated with significant reduction of ventricular arrhythmias in patients with LBBB. (Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy [MADIT-CRT]; NCT00180271)

Photoplethysmographic Measurement of Arterial Stiffness in Polish Patients with Long-COVID-19 Syndrome&mdash;The Results of a Cross-Sectional Study

The coronavirus disease 2019 (COVID-19) is associated with an increase in the incidence of cardiovascular diseases (CVD) that persists even several months after the onset of infection. COVID-19 may also have an impact on arterial stiffness, which is a risk factor for CVD. We aimed to analyze if and to what extent arterial stiffness measured by photoplethysmography differed among COVID-19 convalescents depending on the acute phase severity and time elapsed since disease onset. A total of 225 patients (mean age 58.98 &plusmn; 8.57 years, 54.7% women) were analyzed after COVID-19 hospitalization at the Cardiac Rehabilitation Department of the Ustron Health Resort (Poland). In the entire study population, no differences were found in the mean values of stiffness index (SI) and reflection index (RI) depending on the severity of the acute COVID-19 and the time since the onset of the disease. There were no differences in the heart rate (HR) according to the severity of acute COVID-19; the mean HR was higher in patients who had COVID-19 less than 12 weeks before the study than in convalescents more than 24 weeks after the acute disease (p = 0.002). The mean values of SI and RI were higher in men than in women (p &lt; 0.001), while the heart rate (HR) was similar in both sexes (p = 0.286). However, multiple linear regression analyses after adjusting for factors influencing arterial stiffness, i.e., sex, age, body mass index, smoking status, hypertension, diabetes, the severity of the acute COVID-19, and the time from the disease onset, confirmed that age, sex, time from disease onset, and diabetes are the most important determinants that could influence arterial stiffness