This is a brief overview of information related to FDA’s approval to market this product. See the links below to the Summary of Safety and Effectiveness Data (SSED) and product labeling for more complete information on this product, its indications for use, and the basis for FDA’s approval.
Product Name: Concerto CRT-D Model C154DWK, Consulta CRT-D Model D224TRK, Maximo II CRT-D Model D284TRK, Concerto II CRT-D Model D274TRK, Protecta CRT-D Model D334TRG, Protecta CRT-D Model D334TRM, Protecta XT CRT-D Model D314TRG, Protecta XT CRT-D Model D314TRM, Consulta CRT-D Model D204TRM, and Maximo II CRT-D Model D264TRM Cardiac Resynchronization Therapy Defibrillators
PMA Applicant: Medtronic, Inc. Cardiac Rhythm Disease Management (CRDM)
Address: 8200 Coral Sea Street , Mounds View, MN 55112
Approval Date: April 4, 2012
Approval Letter: http://www.accessdata.fda.gov/cdrh_docs/pdf/p010031a.pdf
What is it? Cardiac Resynchronization Therapy Defibrillators (CRT-D) are implantable cardioverter defibrillators (ICDs) that also deliver cardiac resynchronization therapy (CRT). These CRT-Ds use small electrical impulses to coordinate heart rhythm and improve blood pumping ability in certain patients with heart failure.
Medtronic CRDM Cardiac Resynchronization Therapy Defibrillators
How does it work? The CRT-D system consists of an implantable pulse generator, made up of a battery and electronic circuitry, connected to three insulated wires (leads). The pulse generator is usually implanted below the collarbone, just beneath the skin. The leads are placed in three different areas:
- One lead is placed in an upper heart chamber (the right atrium)
- A second lead is placed in a lower right heart chamber (the right ventricle)
- A third lead is placed in a coronary vein on the outer surface of the lower left heart chamber (the left ventricle)
When the device is functioning as an ICD, it senses dangerous abnormal heart rhythms (arrhythmias) and attempts to shock the heart back into a normal rhythm. The CRT portion of the device coordinates the beating of the left and right ventricles so that they work together more effectively to pump blood throughout the body.
When is it used? TheMedtronic CRT-D is used in certain patients who have:
- Heart failure despite taking heart failure medicines, and
- An abnormal heart rhythm problem that may cause the lower chambers of the heart to beat in an uncoordinated manner.
Medtronic CRT-Ds are used in patients with heart failure who receive prescription drug therapy for heart failure and who meet any one of the following classifications:
- Moderate to severe heart failure with ejection fraction (*EF) less than or equal to 35% and a prolonged **QRS duration.
- Left bundle branch block (***LBBB) with a QRS duration greater than or equal to130 milliseconds (ms), EF ejection fraction less than or equal to 30%, and mild heart failure (NYHA Functional Class II).
* Ejection fraction is the fraction of blood pumped out of ventricles with each heart beat.
** QRS is a name for some of the signals seen on a typical electrocardiogram, which is a picture of the electrical activity of the heart.
***Normally, electrical impulses travel down both the left and right branches of the heart’s electrical system at the same speed, and therefore, both ventricles contract at the same time. In LBBB, the impulses traveling down the left side are blocked so that the left ventricle contracts slower than the right.
What will it accomplish? Together, the defibrillation therapy and the cardiac resynchronization therapy will:
- Help coordinate the beating of the heart.
- Deliver a lifesaving shock to attempt to return the heart to normal rhythm.
- Reduce the patient's risk of death or going to the hospital for heart failure.
- Improve the patient’s ability to engage in physical activity.
- Relieve some of the symptoms associated with heart failure in moderate to severe heart failure patients, including shortness of breath and fatigue during exercise, which may result in a better quality of life.
The safety of these commercially available devices was examined in the clinical trials only to see if new issues might be identified with its use in a different population of patients. The patients studied were those having left bundle branch block (LBBB) with a QRS duration greater or equal to 130 ms, ejection fraction (EF) less or equal to 30%, and mild heart failure (NYHA Functional Class II). No such issues were identified and the safety was re-affirmed.
When should it not be used? All models noted above should not be used in patients having:
- A unipolar pacemaker
- Incessant ventricular tachycardia (VT) or ventricular fibrillation (VF) or
- Chronic atrial tachyarrhythmia without VT or VF (except for the Maximo II Models D284TRK and D264TRM)
Additional information: The Summary of Safety and Effectiveness Data and labeling are available online.
Implantable Cardioverter Defibrillators:
- NIH National Heart Lung and Blood Institute
Cardiac Resynchronization Therapy