ORLANDO (CNNMoney.com) -- The cause of implantable heart defibrillators took a hit Tuesday when researchers reported the results of two studies that failed to reach their objectives. The results, which were reported at the annual conference of the American Heart Association, missed their endpoints - the scientific goal for success. Both studies focused on a type of implant called cardiac resynchronization therapy. The implants, which work like pacemakers, can shock the heart back into action when it stops beating and coordinate the rhythm of the ventricles of the heart.
