At the beginning, the patient receives medication for relaxation and pain relief. Two sheaths are inserted into the patient's artery and vein from the groin, then a temporary pacemaker is passed through the venous system to the heart's right ventricle.
With a coronary angiogram, the cardiologist localizes the origins of the septal artery, then inserts a balloon-tipped catheter in this region. As the balloon is inflated, it temporarily blocks the septal artery.
After confirming by echocardiography that the balloon position is correct, the cardiologist injects 2-5 cc of alcohol which then causes the muscle cells in this area to shrink and die. The scar tissue that forms in this region is thinner than the hypertrophied heart muscle and is thus less likely to obstruct blood flow.
This balloon is deflated and removed within five minutes, and angiography is performed to confirm the occlusion in the targeted septal artery.
The cardiologist checks that the pressure gradient within the left ventricle is reduced following the alcohol injection by inserting a catheter and measuring pressures. The temporary pacemaker is then anchored in place with sutures. The patient is monitored in the coronary care unit and if there are no issues with the conduction system of the heart, the temporary pacemaker is removed after 24-48 hours.
This procedure generally requires a three-day hospital stay, if there are no complications. The entire procedure is performed under local anesthesia. Between 5 and 10% of patients undergoing septal ablation develop a conduction abnormality and require a permanent pacemaker.
Septal ablation is often the best option for elderly patients and those with advanced medical conditions who are unable to tolerate open-surgery.