The authors report no conflicts of interest for the published content.
Cardiac resynchronization therapy is known to improve clinical outcomes in patients with heart failure and left ventricular dyssynchrony. However, the optimal positioning of the right ventricular lead is unknown, and there is conflicting data on the acute hemodynamic effects and long-term outcomes. Here, we present a case of a patient who underwent implantation of a dual-chamber pacemaker for complete heart block, but who after three months, still had symptoms consistent with New York Heart Association (NYHA) Class IV heart failure. After optimal medical therapy failed and a left ventricular lead was placed, he still remained symptomatic, so the right ventricular lead was repositioned from the right ventricular outflow tract to the right ventricular apex. Afterwards, the patient’s symptoms improved from NYHA Class IV to NYHA Class II, and his left ventricular ejection fraction improved from 20% to 45%.
Cardiac resynchronization therapy (CRT) improves clinical outcomes in patients with heart failure and left ventricular dyssynchrony.
We present an 80-year-old African-American male with type II diabetes mellitus, hypertension, and impaired renal function who presented with symptomatic complete heart block. An echocardiogram showed normal-sized atria and ventricles, and normal left ventricular function with an ejection fraction (EF) of 60%.
The patient underwent successful implantation of a dual-chamber pacemaker for symptomatic complete atrioven-tricular block. The right ventricular pacing lead was placed at the RVOT
At this point, the possibility of heart failure induced by right ventricular pacing was considered, and a left ventricular lead was placed in the posteriorlateral branch of the coronary sinus three months after initial implantation of the pacemaker. Despite an upgrade to a biventricular pacemaker for resynchronization therapy, however, the patient remained symptomatic, and his left ventricular function failed to improve. It was decided then to reposition the right ventricular lead from the RVOT to the right ventricular apex. This was successfully performed seven months after the initial implantation of the pacemaker, with the hypothesis that this would alter the activation vector to promote myocardial remodeling
Even though CRT has been well studied, there is a lack of data regarding optimal right ventricular lead placement. One study has shown that RVOT pacing improves cardiac output compared with apical lead placement.
Chest radiograph of a dual-chamber pacemaker implanted with right ventricular lead in the right ventricular outflow tract.
Chest radiograph of the repositioning of the right ventricular pacing lead into the right ventricular apex.