Cardiac Resynchronization Therapy for Patients With Left Ventricular Systolic Dysfunction

Abstract

EART FAILURE IS THE FASTest growing cardiovascular diagnosis in the United States, with a community prevalence of 2.5% in adults, and the direct and indirect costs of heart failure exceed $33 billion per year. 1 Despite many advances in diagnosis and pharmacotherapy for heart failure during the past 2 decades, morbidity and mortality remain high and quality of life is poor for many patients. Thus, there is increasing enthusiasm for the therapeutic potential of atrial-synchronized biventricular pacemakers (cardiac resynchronization therapy [CRT]) in patients with heart failure and left ventricular (LV) systolic dysfunction. CRT is designed to eliminate the delay in activation of the LV free wall found in many patients with LV systolic dysfunction and thereby improves me-See also Patient Page.

Assessing the Prevalence of Mechanical Dyssynchrony with Activity in Patients with Low Ejection Fraction and Narrow QRS at Rest

“…The proposed mechanism includes both improved pump efficiency and reversal of deleterious myocardial remodeling. Results from mechanistic studies, observational evaluations, randomized controlled trials and their meta-analyses have consistently demonstrated significant improvement in quality of life, functional status, exercise capacity, hospitalization, and mortality in patients with New York Heart Association (NYHA) class III and IV HF and electrical dyssynchrony who are randomized CRT [7]. More recently the MADIT-CRT trial demonstrated improvement in all cause mortality and progression of heart failure in patients with NYHA class I and II, prompting expansion of CRT indications to include all patients with heart failure with impaired systolic function and left bundle branch block morphology on EKG [8].…”

Terapia de resincronización en pacientes con insuficiencia cardiaca: experiencia acumulada de 10 años

“…Las características generales de nuestros pacientes son comparables a las series internacionales 12 , aunque existen algunas diferencias importantes. Así por ejemplo, los estudios con distribución aleatoria han excluido sistemática-mente a pacientes en FA, que en nuestra serie correspondían a 1 de cada 5 sujetos.…”

Indication of Implantable Devices for the Prevention of Sudden Cardiac Death

“…20) The clinical applications of the pacing method known as CRT alone (CRT-P) began by using an epicardial lead in 1994. 21) Recent meta-analysis 11,22,23) demonstrated that CRT-P improved LVEF, QOL, and functional status, and reduced hospitalization for heart failure and mortality from all causes. However, it has not been determined whether CRT-P has a potential to suppress lethal arrhythmia or sudden cardiac death 22) (Figure 2).…”

“…The implantation of ICD, CRT-D and CRT-P are useful for improving the prognosis and/or sudden cardiac death event rate in patients with heart failure and/or fatal ventricular arrhythmias (ventricular tachycardia: VT/ventricular fibrillation: VF). [4][5][6][7][8][9][10][11] This review paper was written mainly to identify the indications for ICD/CRT-P or CRT-D on the basis of the 2006 JCS guidelines. 3) Further, the usefulness of pharmacological tests for the choice of effective drugs to treat lethal arrhythmia and electrophysiological tests for prognosis, especially in patients with dilated cardiomyopathy, have been questioned recently.…”