Electrical activation was assessed as the time from QRS onset to LVLP electrogram (QLV). Patients were then followed LY3039478 in vivo for clinical events. Results In 75 patients, multivariable logistic modeling accurately identified the 40 patients (53%) with CRT response (area under the curve: 0.95 [p smaller than 0.0001]) based on CURE (odds ratio [OR]: 2.59/0.1 decrease), delayed circumferential contraction onset at LVLP (OR: 6.55), absent LVLP scar (OR: 14.9), and QLV (OR: 1.31/10 ms increase). The 33% of patients with CURE smaller than 0.70, absence of LVLP scar, and delayed LVLP contraction
onset had a 100% response rate, whereas those with CURE bigger than = 0.70 had a 0% CRT response rate and a 12-fold increased risk of death; the remaining patients had a mixed response profile. Conclusions Mechanical, electrical, and scar properties at the LVLP together with CMR mechanical dyssynchrony are strongly associated with echocardiographic CRT response and clinical events after CRT. Modeling these findings find more holds promise for improving CRT outcomes. (C) 2014 by the American College of Cardiology Foundation”
“Aims Dysregulation of autonomic nervous system activity can trigger ventricular arrhythmias and sudden death in patients with heart failure. N-type Ca2+ channels (NCCs) play an important role in sympathetic nervous
system activation by regulating the calcium entry that triggers release of neurotransmitters from peripheral sympathetic
nerve terminals. We have investigated the ability of NCC blockade to prevent lethal arrhythmias associated with heart failure. Methods and results We compared the effects of cilnidipine, a dual N- and L-type Ca2+ channel blocker, SB203580 datasheet with those of nitrendipine, a selective L-type Ca2+ channel blocker, in transgenic mice expressing a cardiac-specific, dominant-negative form of neuron-restrictive silencer factor (dnNRSF-Tg). In this mouse model of dilated cardiomyopathy leading to sudden arrhythmic death, cardiac structure and function did not significantly differ among the control, cilnidipine, and nitrendipine groups. However, cilnidipine dramatically reduced arrhythmias in dnNRSF-Tg mice, significantly improving their survival rate and correcting the imbalance between cardiac sympathetic and parasympathetic nervous system activity. A beta-blocker, bisoprolol, showed similar effects in these mice. Genetic titration of NCCs, achieved by crossing dnNRSF-Tg mice with mice lacking CACNA1B, which encodes the alpha 1 subunit of NCCs, improved the survival rate. With restoration of cardiac autonomic balance, dnNRSF-Tg; CACNA1B(+/-) mice showed fewer malignant arrhythmias than dnNRSF-Tg; CACNA1B(+/+) mice. Conclusions Both pharmacological blockade of NCCs and their genetic titration improved cardiac autonomic balance and prevented lethal arrhythmias in a mouse model of dilated cardiomyopathy and sudden arrhythmic death.