Cardiac resynchronization therapy


Cardiac resynchronization therapy is a treatment given to heart failure patients. During the procedure, a specialized biventricular pacemaker or ICD (implantable cardioverter defibrillator) is implanted. The ICD is a small battery-run device that is placed under your skin, through a vein and into your heart chamber, to re-coordinate the movements of the left and right ventricles of the heart, monitoring and treating abnormal heart rhythms and improving its pumping ability.

Your doctor may recommend that you have an ICD placed if you:

  • Had heart attacks in the past that left you with a weakened heart muscle
  • Survived a cardiac arrest in the past
  • Had ventricular tachycardia or ventricular fibrillation in the past
  • Have a low ejection fraction of less than 35 percent, which means that your heart muscle is not as strong as a normal heart muscle


Depending on the specific condition, arrhythmias may be caused by:

  • Abnormal contractions of the atria (the heart’s upper chambers) or ventricles (lower chambers)
  • Rapid circuits in the atria
  • Electrical impulses originating in the wrong area of the heart
  • Abnormality in the heart’s conduction (electrical) system
  • Malfunction of the sinoatrial node (the heart's natural pacemaker)
  • An extra electrical pathway is present
  • Scarred tissue from previous heart attacks


LARIAT (left atrial appendage occlusion) surgery is an innovative catheter-based percutaneous procedure that uses sutures to tie off the left atrial appendage (LAA). This process helps to prevent blood clots that can lead to stroke in patients with atrial fibrillation, or "AFib" (an abnormal heart rhythm). This procedure is the only minimally invasive treatment option for patients who have AFib but cannot take blood thinners due to an underlying medical condition. 

Cardiac ablation
Cardiac ablation is a procedure done to treat heart arrhythmia, such as rapid or irregular heartbeat. In cardiac ablation, catheters are passed through blood vessels to the heart. The abnormal electrical conducting area is located, and a form of energy is delivered. There are several forms of ablation: the energy may be radiofrequency (heat), laser, or cryo (very cold). Cardio ablation scars the abnormal area, thus stopping the abnormal path of conduction. The procedure usually takes two to three hours, but can last longer. A doctor trained in the electrical system of the heart, a cardiac electrophysiologist, does the procedure.

Cardiac defibrillator implantation
An ICD is implanted under the skin, most often in the shoulder area just under the collarbone. It senses the speed of the heartbeat and delivers a small electrical shock to slow the heart when it exceeds the programmed rate. Newer ICDs also can function as pacemakers by delivering an electrical signal to regulate a heart rate that is too slow.

Permanent pacemaker implantation 
Irregular heart rhythms can be managed by a pacemaker. Temporary pacemakers are external, while permanent pacemakers can be inserted and programmed in one of our electrophysiology labs. A permanent pacemaker is a small device implanted under the skin (most often in the shoulder area just under the collarbone), that sends electrical signals to start or regulate the heartbeat if the heart's natural pacemaker is not functioning properly.

Additional electrophysiology procedures for arrhythmias
Electrophysiology procedures extend beyond ablations and pacemaker implantations to include many diagnostic tests and therapies to assist in the treatment of arrhythmias:  

Cardioversion therapy sends a precisely timed electrical shock through the chest to the heart to correct an abnormal heart rhythm. The patient is connected to an electrocardiogram (ECG) monitor and a defibrillator. This synchronized electrical shock is delivered through special paddles applied to the skin of the chest and back.


If you receive a shock from your ICD:

  • Stay calm and sit or lie down. Think about how you feel. If you are not alone, tell the person(s) with you how you feel.
  • When a person with an ICD gets a shock, it feels like a thump in the chest. If someone is touching you when you get the shock, they will not be in danger. They may see your chest and muscles tighten and your body may jump.
  • If you receive one shock, and then feel okay after the shock, you must call our electrophysiology (EP) office.
  • If you receive two or more shocks, or if you continue to feel bad or you are not awake, you or someone helping you should call 911 and go to the nearest emergency room.
  • Have a plan about what to do if you receive a shock. Keep your identification card and a list of your medicines with you at all times. Talk to your family and friends about what should be done if your ICD sends a shock.


You should discuss your routine medicines with your doctor to see if any changes should be made before your ICD insertion. Your doctor will discuss the risks, benefits, and choices with you. You then will be asked to sign an informed consent giving permission to have the procedure. Do not eat or drink anything after midnight the night before your surgery. Ask your doctor what medicines you should stop or continue to take, and whether you may take them with a sip of water.

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