Alcohol septal ablation is a procedure used to treat obstructive hypertrophic cardiomyopathy (HCM). It is a minimally invasive procedure performed when severe symptoms cannot be controlled with drugs. In obstructive HCM, the wall (septum) between the heart’s ventricles thickens until it interferes with blood flow to the body. Alcohol septal ablation creates a tiny, managed heart attack in the abnormally thickened heart tissue. The damaged tissue dies and is replaced by thinner scar tissue, restoring blood flow out of the heart.
Alcohol septal ablations are conducted in the Cardiac Catheterization Laboratory of the Heart Institute.
- The doctor explains the procedure, outlining for the patient and family members its potential benefits, risks, and complications, and asks the patient to provide informed consent. The test cannot be conducted without this consent.
- The patient is given a local anesthetic (painkiller) at the site of catheter insertion, an anticoagulation drug, a sedative if needed or requested, and an injection of dye to allow the doctors to guide the catheter through the body using real-time X-rays and echocardiography.
- A thin catheter (tube) with a balloon at the end is inserted into a blood vessel in the groin and guided, using imaging, to the heart.
- When the catheter reaches the blocked artery, the balloon is inflated to stop blood flow.
- A small amount of pure alcohol is pushed through the catheter into the artery to destroy the excess tissue blocking blood flow. Some mild chest pain or discomfort may be experienced during this part of the procedure.
- After a few minutes, the balloon and catheter are removed.
- The patient will remain in the hospital for several days for monitoring, and activity is restricted for several months to allow for full recovery.
- The patient will need to return for follow-up visits to evaluate healing and heart function.
When used in carefully screened patients, alcohol septal ablation is more than 90 percent effective in relieving symptoms of obstructive HCM. If alcohol septal ablation does not work for a patient, a surgical procedure may be necessary.
The most common (though rare) side effect of alcohol septal ablation is injury to the electrical pathway of the heart (called a complete heart block). This results in a very slow heart beat, requiring implantation of a permanent pacemaker. Other unusual side effects include heart attack, heart infection, and damage to the heart from the catheter, which requires emergency surgery.