PROTECT-PACE STUDY - The Protection of Left Ventricular Function During Right Ventricular Pacing

This study will be done in patients who require the implantation of a cardiac pacemaker (an electronic device that controls the heartbeat) for complete heart block (a heart rhythm abnormality resulting in a slow heart beat). Pacemakers regulate the heart beat by delivering pulses of electricity through special wires (pacing leads) which are placed inside the heart. This study will compare two groups of pacemaker patients. Each group will have their pacing leads placed in a particular location in the heart. The purpose of the study is to show whether the position used in one group is better for maintaining effective heart function compared to the position used in the other group. The leads in one group will be placed in a position called the Right Ventricular Apex. This is the traditional and most frequently used position for pacemaker leads. The leads in the other group will be placed in a position called the Right Ventricular High Septum. This is a less commonly used position, but may result in health benefits for the patients compared with the Right Ventricular Apex.