InSync III Marquis Model 7279 Cardioverter Defibrillator Cardiac Resynchronization System
InSync III Marquis Model 7279 Cardioverter Defibrillator Cardiac Resynchronization System
People who have a dangerously fast heart beat, or whose heart is at risk of stopping beating, may be in need of an electronic device called an implantable cardioverter defibrillator (ICD). An ICD is implanted surgically just under the skin in the upper chest area and it sends a strong electrical impulse, or shock, to the heart to return it to a normal rhythm. If the heart is beating too slowly or at an abnormal rhythm, an ICD can also pace the heart to return the heart to its normal rhythm.
The InSync III Marquis device can change the timing of when the left and right ventricles of the heart are paced to beat. This is called "V to V timing". V to V timing may further improve the pumping function of the heart. The purpose of this study is to determine whether or not this V to V timing feature of the InSync III Marquis system is safe and effective.
Inclusion Criteria:
Subject has, or is at risk of having, a heart beat that is too fast and his/her doctor has determined the need for an implantable cardioverter defibrillator.
Subject is on optimal medical treatment for heart failure.
Subject has reduced left ventricular ejection fraction (LVEF≤35%). (LVEF is a measurement of how well the left ventricle pumps blood out to the rest of the body. The higher the LVEF the more blood the ventricle is pumping.)
Subject who has heart failure which severely limits daily activities (NYHA Class III) or subject who has severe heart failure and should always be resting (NYHA Class IV)
Subject who has a QRS≥130ms (The QRS interval is a measurement of how the electrical signal involved in a heart beat travels/conducts through the ventricles. A wide QRS (more than 120 ms) suggests that there is a conduction problem (or block) in the ventricles.)
Subjects with a left ventricular end diastolic dimension (LVEDD≥55mm). (The LVEDD is a measurement taken during an echocardiogram that is one indication of the health of the left ventricle.)
Exclusion Criteria:
Subject has unstable chest pain, heart surgery within past 3 months
Subject has liver function tests greater than 3 times normal limits
Subject has chronic (permanent) atrial arrhythmias (fast heart beats in the upper chamber(s) of the heart)