European Clinical Trial Shows Potential For New Beating-Heart Bypass Surgery

(WASHINGTON, DC) - A clinical study appearing in the just released issue of the Annals of Thoracic Surgery suggests that an experimental medical device allows a cardiothoracic surgeon to perform heart bypass surgery on a beating-heart with outcomes comparable to traditional heart bypass surgery. The study also implies that patients undergoing the experimental procedure experienced fewer side effects than patients receiving traditional heart bypass surgery.

Dr. Urban Lönn and colleagues with the Linköping Heart Center, University Hospital in Linköping, Sweden examined the effectiveness of performing open chest bypass surgery on a beating heart with support from an axial flow heart assist pump known as a Hemopump (Medtronic, Minneapolis, MN). By relying on the heart pump during surgery, patients were able to breathe and circulate their body's blood supply without the support of a heart and lung machine during their bypass operation.

The authors write, "Hemopump supported coronary artery bypass grafting was shown to be a safe and feasible method when compared with traditional (heart bypass) surgery (with the potential benefits of reduced operative bleeding and myocardial damage). The procedure takes no longer to perform, time of cardiac support during the operation does not differ, and no device related complications were seen… It should be pointed out that the results from this study only apply narrowly to the short-term postoperative period, and the real test of the method can only be done in large long-term studies."

In this study, the authors relied upon an "open-chest" for the insertion of the pump into the patient's left ventricle. Upon insertion, the pump was utilized to circulate blood through the heart. This procedure allowed the cardiothoracic surgeons to complete the heart bypass on the patient's beating-heart.

The procedure used by the authors differs from other "minimally invasive beating-heart bypass surgeries" that do not use a chest opening procedure and rely upon either a beating-heart or a non-beating-heart to complete the surgery. The experimental procedure also differs from traditional open heart bypass surgery that requires mechanical support from a heart-lung machine for a patient's respiratory and circulatory function to enable a surgeon to operate on non-beating- heart.

The randomized study compared the results of 32 patients. 16 patients were assigned to the Hemopump group while the remaining 16 patients received traditional heart bypass surgery. Four patients from each group developed complications after surgery.

Complications in the pump group included a temporary rise in one patient's creatinine levels, a superficial sternal wound infection was experienced by another, one patient developed heart failure in their right ventricle and was converted to traditional bypass as a result, and the other developed a subendocardial infarction during the operation.

In the traditional bypass surgery group complications included postoperative bleeding for one patient, reversible neurologic symptoms in the left arm for another, and respiratory complications for two patients.

The Hemopump is not currently FDA approved for use in the United States.

The Society of Thoracic Surgeons is the membership society for thoracic surgeons in the United States. With over 4,100 members, the society represents the surgical practice areas of cardiac surgery (heart), general thoracic surgery (pulmonary, lung, esophagus, and mediastinum), pediatric thoracic surgery, and transplant surgery. The society is committed to saving, extending, and improving the quality of life for all Americans.