A pacemaker does not cause the heart muscle to contract more forcefully; therefore, it does not help heart failure, except in some cases where a very slow heart rate was contributing to the heart failure. In a special group of patients with heart failure and intraventricular conduc¬tion delay pacing the heart may decrease the recurrence of heart failure (see the chapters Heart Failure and Bundle Branch Block).
A pacemaker does not increase the blood supply through the coronary arteries; therefore, it does not help chest pain or angina or prevent a heart attack. It does not replace the usual cardiac medications prescribed for various heart conditions. Prescribed medications must be contin¬ued for heart failure, angina, or other conditions that may exist. A pacemaker is a great device but it does only what it is designed to do. It stimulates the electrical system of the heart so that the heart beats at the correct time and at an appropriate rate. A pacemaker can prolong life provided the problem is a slow a heart rate or no heartbeat because of heart block.