Effects of Upgrading From Right Ventricular Pacing to Cardiac Resynchronization Therapy and Comparison With Dual-Chamber Defibrillator

100 patients receiving de-novo CRT, 38 patients upgrading from RV pacing to CRT, and 169 patients receiving a DDDR-ICD implantation were included the study. Inclusion criteria were left ventricular ejection fraction lower than 35% and either QRS longer than 130ms for CRT groups or QRS≤120ms for the DDDR-ICD group. Primary endpoints were all-cause mortality and hospitalization for heart failure during a follow-up period extending up to 5 years.

Inclusion criteria

De novo CRT group:

• Sinus rhythm,
• age higher than 18,
• EF lower than 35%,
• New York Heart Association (NYHA) class II-IV,
• QRS >130 ms,
• patients with atrial fibrillation (AF) who converted to sinus rhythm and who remained symptomatic despite 3-6 months of guideline-directed medical therapy.

CRT upgrade group:

• Sinus rhythm,
• age higher than 18,
• EF lower than 35%,
• NYHA class II-IV,
• QRS duration >130 ms with RV pacing,

-> 20% RV pacing rate,

• patients with AF who converted to sinus rhythm, at least 6 months since pacemaker implantation, and symptomatic despite 3-6 months of guideline directed medical therapy.

DDDR ICD group:

• Sinus rhythm,
• age higher than 18,
• EF lower than 35%,
• QRS ≤120 ms,
• NYHA class II-IV,
• patients with AF converted to sinus rhythm,
• receiving guideline-directed medical therapy.

Exclusion criteria

• patients with atrial fibrillation
• LV EF higher than 50 %
• NYHA Class 1
• Patients with active infection or cancer