THE PULSE GENERATOR AND LEADS ARE INDICATED AS FOLLOWS: 1) THE INSYNC MODEL 8040 PULSE GENERATOR IS INDICATED FOR THE REDUCTION OF THE SYMPTOMS OF MODERATE TO SECERE HEART FAILURE (NYHA FUNCTIONAL CLASS III OR IV) IN THOSE PATIENTS WHO REMAIN SYMPTOMATIC DESPITE STABLE, OPTIMAL, MEDICAL THERAPY, AND HAVE A LEFT VENTRICULAR EJECTION FRACTION <= 35% AND A QRS DURATION = 130 MS. 2) THE ATTAIN LV MODEL 2187 LEAD HAS APPLICATION AS PART OF A MEDTRONIC BIVENTRICULAR PACING SYSTEM. 3) THE ATTAIN CS MODEL 2188 LEAD HAS APPLICATION WHERE PERMANENT ATRIAL, OR FUAL-CHAMBER PACING SYSTEMS ARE INDICATED, OR AS PART OF A MEDTRONIC BIVENTRICULAR PACING SYSTEM.