Comparison of right ventricular outflow tract and apical lead permanent pacing on cardiac output

In 1992, De Cock et al(1) presented a series of 15 patients showing a 17% improvement-in cardiac index with right ventricular (RV) outflow tract temporary pacing compared with the RV apex. Since that time, other investigators have shown an improvement in cardiac output (CO) with septal pacing and we presented a series of 15 and, subsequently, 58 patients having increased CO with permanent RV outflow tract implants. We present our experience with 89 patients, evaluating CO and cardiac index pacing from the apex versus RV outflow tract at the time of implant.