Background: The aim of this study was to evaluate whether the benefit of cardiac resynchronization therapy with an implantable defibrillator (CRT-D) may differ among classes of indications to device therapy.
Methods: All-cause mortality, first hospitalization for non-fatal heart failure, stable improvement of NYHA functional class (responders), and implant-related complications were evaluated retrospectively in 103 patients selected among those (n = 133) who received consecutively CRT-D between 2006 and 2009. Patients were divided into three groups: group IA (n = 65) included patients receiving CRT-D for a class IA indication; group IIa (n = 26) included patients with atrial fibrillation and QRS ≥ 130 ms receiving CRT-D for a class IA indication; nonconventional group (NC) (n = 12) included patients with an indication to defibrillator implantation extended to CRT-D because of NYHA class III-IV and echocardiographic evidence of electromechanical dyssynchrony. Echocardiographic examination was performed in all patients to identify wall target for left-side lead placement.
Results: Group IIa patients were slightly older than group IA patients (p<0.05); gender distribution, left ventricular ejection fraction at implantation, ischemic etiology, and heart failure treatment were comparable among groups (all p>0.5), except for a higher digitalis use in group IIa patients (p<0.05). In a mean observation period of 3 years (up to December 2010), the rates of fatal events (IA: 22%, IIa: 23%, NC: 20%), rehospitalization for worsening heart failure (IA: 30%, IIa: 33%, NC: 22%), clinical responders (IA: 78%, IIa: 78%, NC: 78%), implant-related complications requiring reintervention (IA: 15%, IIa: 19%, NC: 25%), including pocket or catheter infections (IA: 5%, IIa: 11%, NC: 8%) were comparable among groups (all p>0.5).
Conclusions: In the "real world", the benefit of CRT-D in advanced heart failure patients might be comparable among class IA, IIa or NC indication.