Mortality, left ventricular ejection fraction, and prevalence of new left ventricular wall motion abnormality at long-term follow-up in patients with implantable cardioverter defibrillators treated with biventricular pacing versus right ventricular pacing.

We investigated left ventricular ejection fraction and new left ventricular wall motion abnormality before pacemaker implantation and at follow-up and mortality at long-term follow-up in 81 patients with implantable cardioverter defibrillators treated with biventricular pacing and in 80 patients with implantable cardioverter defibrillators treated with DDDR-70 right ventricular pacing. At 23-month follow-up, the left ventricular ejection fraction decreased from 36% to 30% in patients treated with right ventricular pacing and increased at 38-month follow-up from 35% to 40% in patients treated with biventricular pacing (P < 0.001). New left ventricular wall motion abnormality developed at 23-month follow-up in 23 of 80 patients (29%) treated with right ventricular pacing and at 38-month follow-up in 7 of 81 patients (9%) treated with biventricular pacing (P < 0.005). Twenty-two of 80 patients (28%) treated with right ventricular pacing died at 45-month follow-up and 8 of 81 patients (10%) treated with biventricular pacing died at 53-month follow-up (P < 0.01).