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BACKGROUND: To evaluate the impact of changes in the filtered QRS duration (fQRS) on signal‐averaged electrocardiograms (SAECGs) from pre‐ to postimplantation on the clinical outcomes in nonischemic heart failure (HF) patients under cardiac resynchronization therapy (CRT). METHODS: We studied 103 patients with nonischemic HF and sinus rhythm who underwent CRT implantation. SAECGs were obtained within 1 week before and 1 week after implantation and narrowing fQRS was defined as a decrease in fQRS from pre‐ to postimplantation. Echocardiography was performed before and 6 months after CRT implantation. The primary outcome was death from any cause. The secondary outcomes were hospitalization due to worsened HF and occurrence of ventricular tachyarrhythmias. RESULTS: Of the 103 CRT patients, 53 (51%) showed narrowing fQRS. Left ventricular end‐diastolic volume and end‐systolic volume were significantly reduced (both p

AimsThe effects of inotropic agents on left ventricular (LV) synchrony in heart failure patients are still unknown. The purpose of this study was to investigate the effects of dobutamine on LV mechanical dyssynchrony and LV systolic performance in patients with dilated cardiomyopathy (DCM) and a narrow QRS using real-time three-dimensional echocardiography (RT3DE).Methods and resultsThirty-three patients with idiopathic DCM and a narrow QRS underwent low-dose dobutamine stress echocardiography (LDSE) with RT3DE. A time-global LV volume curve and time-regional LV volume curves were derived from RT3DE. Regional LV stroke volumes were summed in each stage, and the dobutamine-induced increase in the sum of regional LV stroke volumes was considered as the sum of regional contractile reserve. Systolic dyssynchrony index (SDI) was calculated as follows: (standard deviation of time to minimal volume for regional LV segments)×100/RR duration. Among the 33 patients, low-dose dobutamine increased global LV stroke volume (SV) in 28 (85%), but decreased global LVSV in the remainder (15%). The sum of regional contractile reserve was modestly correlated with the dobutamine-induced increase in global LVSV (R=0.57, p

Background Paroxysmal nocturnal dyspnea (PND) is a common symptom for patients with acute decompensated heart failure (ADHF). Some symptoms of PND are similar to those of sleep apnea (SA) which might be associated with overnight worsening hemodynamics in failing hearts. However, the association between PND, SA, and overnight change in hemodynamics in patients with heart failure remains uncertain. Methods We studied 28 consecutive patients with reduced ejection fraction who were hospitalized with ADHF. Plasma atrial natriuretic peptide (ANP) levels were measured before and after overnight sleep study. PND was defined as having an episode of PND prior to hospitalization for ADHF. Results Ten (36%) patients had a history of PND. Respiratory disturbance index (the frequency and severity of sleep apnea) was an independent factor associated with a history of PND (odds ratio 1.24, 95% confidence interval 1.05–1.47, p = 0.011). In those without PND, plasma ANP levels decreased from before sleep to after waking, whereas in those with PND it increased (p = 0.011). In addition, overnight change in plasma ANP levels was independently associated with respiratory disturbance index (p = 0.035). Conclusion These results thus suggest that in patients with ADHF, SA might be a predisposing cause of PND in association with overnight worsening hemodynamics.