Of 200 patients who had permanent cardiac pacemakers implanted between 1961 and 1971, 70 had epicardial catheters with 11% mortality and 30% major complications, related to wire breakage or skin erosion. The remainder (130) had endocardial catheters with 2% mortality, and 31.5% major complications related to erosion of skin and perforations of the heart. The "trapped endocardial electrode," unique to the system was encountered 11 times. It is concluded that endocardial catheters are preferable to epicardial.
Imparato AM, Kim GE. Electrode Complications in Patients With Permanent Cardiac PacemakersTen Years' Experience. Arch Surg. 1972;105(5):705-710. doi:10.1001/archsurg.1972.04180110030009