BACKGROUND Electric left ventricular lead position, assessed by the electric delay from the beginning of the QRS complex to the local LV electrogram (QLV), was found in previous studies to be a strong predictor of short-term response to cardiac resynchronization therapy. We hypothesized that suboptimum electric position of the left ventricular lead is associated with an excess of heart failure ...

We describe the case of a 37-year-old woman who presented with complete right bundle branch block and right axis deviation. She was admitted to our hospital due to severe heart failure and was dependent on inotropic agents. Cardiac resynchronization therapy was initiated but did not improve her condition. After the optimization of the pacing timing, we performed earlier right ventricular pacing...

A 69-year-old woman with idiopathic dilated cardiomyopathy and chronic heart failure experienced repeated hospital admissions for acute pulmonary edema with no recognizable precipitating factor. Worsening mitral regurgitation was triggered by exercise echocardiography and significant intraventricular dyssynchrony was elicited by low-dose dobutamine stress echocardiography. After cardiac resynch...

In this issue of iJACC (JACC: Cardiovascular Imaging), Botvinick et al. (1) perform a complex study involving the performance of equilibrium radionuclide myocardiography with phase analysis during ventricular tachycardia. The authors identify specific characteristics that define tolerability of the arrhythmia in individual patients. Most of these discriminating factors in the 2 patient groups i...

SEE PAGE 969 C ardiac resynchronization therapy (CRT) is a highly effective treatment for some patients with heart failure. Current guidelines recommend the implantation of CRT devices in patients with left ventricular (LV) dysfunction and electrical dyssynchrony, evidenced by a left bundle branch block (1). Unfortunately, not all patients suitable for CRT derive symptomatic benefit—an unsatisf...

ardiac Resynchronization Therapy art 2—Issues During and After Device mplantation and Unresolved Questions eroen J. Bax, MD,* Theodore Abraham, MD, FACC,† S. Serge Barold, MD, FACC,‡ le A. Breithardt, MD,§ Jeffrey W. H. Fung, MD, Stephane Garrigue, MD, PHD,¶ ohn Gorcsan III, MD, FACC,# David L. Hayes, MD, FACC,** David A. Kass, MD,† uhani Knuuti, MD, PHD,†† Christophe Leclercq, MD, PHD,‡‡ Cecil...

Cardiac Resynchronization therapy has become an important management tool in adults with heart failure and dilated cardiomyopathy. The role of CRT in children with CHF is still unclear. Evidence is slowly emerging in the pediatric cardiology literature that CRT may have an important and useful role in certain select populations with CHF. These include patients with complete heart block who deve...

C ase presentation: A 55-year-old female patient underwent implan-tation of a cardiac resynchronization therapy (CRT) defibrillator 6 years ago owing to nonischemic dilated cardio-myopathy. Her left-ventricular (LV) ejection fraction (EF) was 28% before implantation, her LV end-diastolic volume index (EDVI) was 144 mL/m 2 , and her LV end-systolic volume index (ESVI) was 104 mL/m 2. Her intrins...

UNLABELLED There have been numerous studies focusing on the assessment of left ventricular mechanical dyssynchrony. These studies are diverse in their purposes, which include more effectively predicting the response to cardiac resynchronization therapy, improving the guidance of the left ventricular lead position, and better prediction of outcome in patients with heart failure. This article rev...