Ann Thorac Surg 2003;76:827
© 2003 The Society of Thoracic Surgeons
Invited commentary
Larry W. Stephenson, MDa
a Division of Cardiothoracic Surgery, Wayne State University School of Medicine, Harper Professional Building, Suite 2102, 3990 John R Street, Detroit, MI 48201, USA
e-mail: lstephen{at}dmc.org
Since Alain Carpentier and Juan Carlos Chachques introduced clinical cardiomyoplasty in 1985, an estimated 1000 of these procedures have been done worldwide. In the phase II clinical trials conducted in the United States under the auspices of the FDA, about 80%–85% of hospital survivors showed improvement in their signs and symptoms for heart failure from several months up to a year, and sometimes much longer.
The phase III randomized clinical trial, again under the auspices of the FDA, commenced in June 1995 and ended in 1998. Slightly more than 100 patients entered this study which was designed to determine the safety of cardiomyoplasty as a treatment for heart failure due to cardiomyopathy. There was a similar improvement in the signs and symptoms of heart failure as in the phase II trial and also when compared with control patients. There was no improvement, however, in survival of the cardiomyoplasty patients when compared to the medically treated randomized controls followed for about two years. This fact and difficulty in recruiting patients into the study resulted in Medtronic, who was sponsoring the study, terminating the phase III trial. This study was thought to need outcomes from about 400 patients for valid statistical comparisons. With Medtronic's withdrawal from the study and their decision to no longer manufacture cardiomyostimulators, cardiomyoplasty from a clinical standpoint was essentially abandoned in the United States.
Some groups in other countries continue to perform this procedure, using other available cardiomyostimulators. As new clinical data and laboratory research becomes available, it is possible that there could be a resurgence of cardiomyoplasty.
The study by Benicio and colleagues in this issue of The Annals is important for a number of reasons. First, their group from São Paulo University has been among the leaders and is one of the most reputable groups in this field for many years. Second, they present their long-term results with cardiomyoplasty over a 10 year period, and compare their results by patients who were initially NYHA Functional Class III versus Functional Class IV. Last, when cardiomyoplasty was first performed, there was controversy as to whether the latissimus dorsi muscle should be stimulated with every heartbeat or every other heartbeat. Their data clearly show that over time the 1:2 mode of stimulation is better.
