Clinical evaluation of combination therapy for biventricular pacing after cardiac surgery in patients with intractable heart failure.

We examined the effectiveness of combination therapy for biventricular pacing after cardiac surgery. We performed biventricular pacing in seven patients until April 2003. The diagnosis of the patients was ischemic cardiomyopathy (ICM) in four patients and dilated cardiomyopathy (DCM) in three patients. The implantation method of biventricular pacing was performed with a myocardial electrode through a median sternotomy. DDD-R and SSI-R were used to perform biventricular pacing. A Y-adapter was connected to a generator so that the 2 leads could be implanted in both the right ventricles (RV) and left ventricles (LV). The clinical symptoms were New York Heart Association (NYHA) classification of 3.7+/-0.3 preoperatively and 1.8+/-0.6 postoperatively, showing a significant improvement (p<0.001). The cardiac index (CI) was 1.9+/-0.2 L/min/m2 preoperatively and 3.0+/-0.6 L/min/m2 postoperatively (p<0.05). The pulmonary capillary wedge pressure (PCWP) was 19.5+/-2.6 mmHg preoperatively and 13.6+/-2.0 mmHg postoperatively, showing a significant improvement (p<0.05). The intracardiac potential and threshold values were: left atrium 1.9+/-1.0 mV, threshold value (PW: 0.45 msec) 2.1+/-0.6 V, LV 4.9+/-4.23 mV, threshold value (PW: 0.45 msec) 2.2+/-1.51 V, and RV 3.6+/-0.9 V, threshold value (PW: 0.45 msec) 2.0+/-0.7 V. The LV and RV threshold values were high. The QRS interval improved from 158.4+/-18.0 msec preoperatively to 110+/-13.4 msec postoperatively, showing a significant reduction. This combination therapy when compared to the use of the biventricular pacing method used at the current time, does have the risks of cardiac surgery, but the clinical symptoms and hemodynamic performance improvement are great.