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Background—The objective of the study was to investigate the effect of cardiac resynchronization therapy (CRT) on cardiac autonomic function.
Methods and Results—This prospective study included 45 consecutive patients with heart failure who received CRT devices with defibrillator and 20 age-matched healthy controls. At baseline, 3 months and 6 months after CRT, we assessed New York Heart Association (NYHA) class, 6-minute walk distance, plasma sympathetic biomarker nerve growth factor, echocardiography, heart rate variability and cardiac presynaptic sympathetic function determined by iodine 123 metaiodobenzylguanidine scintigraphy. After CRT, NYHA class improved by 1 class (p<0.001), p="0.004)" p="0.004)," p="0.03)," p="0.01)." p="0.003)," p="0.003)">
Conclusions—CRT improved sympathetic function. Cardiac sympathetic reserve may be a marker for the reversibility of failing myocardial function.
Background—Doppler echocardiography is currently applied for the assessment of left ventricular (LV) and right ventricular (RV) hemodynamics in patients with cardiovascular disease. However, there are conflicting reports about its accuracy in patients with unstable decompensated heart failure. The objective of this study was to evaluate the accuracy of the technique in patients with unstable heart failure.
Methods and Results—Consecutive patients with decompensated heart failure had simultaneous assessment of LV and RV hemodynamics invasively and by Doppler echocardiography. In 79 patients, the non-invasive measurements of stroke volume (r=0.83, p<0.001), r="0.83," r="0.51," p="0.009)," r="0.85,">15 mmHg (AUC from 0.86 to 0.92). The recent ASE/EAE guidelines were highly accurate (sensitivity : 98%, specificity : 91%) in identifying patients with increased wedge pressure. In 12 repeat studies, Doppler echocardiography readily detected the changes in mean wedge pressure (r=0.75, p=0.005) as well as changes in pulmonary artery systolic pressure and mean right atrial pressure.
Conclusions—Doppler echocardiography provides reliable assessment of LV hemodynamics in patients with decompensated heart failure.