Transplant surgery to correct the most common type of genetic heart disease yields similar short-term and potentially greater long-term survival rates as transplant surgery for other heart diseases, according to research reported in Circulation: Heart Failure, an American Heart Association journal.
Researchers found similar survival rates one year after heart transplant surgery between hypertrophic cardiomyopathy (HCM) patients (85 percent) and those with other kinds of heart disease (82 percent). Five years post-surgery, survival rates began to diverge with 75 percent of HCM and 70 percent of other patients surviving. At the 10-year mark, survival rates in both groups dropped, although they remained significantly higher in the HCM patients (61 percent) than in those with other heart diseases (49 percent).
"Patients with this disease who are undergoing transplant can expect reasonable long-term survival rates," said Martin S. Maron, M.D., lead author and assistant professor of medicine, director of the Hypertrophic Cardiomyopathy Center, and co-director of Advanced Cardiac Imaging at Tufts Medical Center in Boston, Mass. "That's a crucial clinical message for this small but important subgroup of patients."
Inflammation of the heart muscle (cardiomyopathy) is a serious, potentially fatal disease that can prevent the heart from pumping blood effectively. In HCM - the second most common form of heart muscle disease - the pumping chamber of the heart, known as the left ventricle, thickens (hypertrophies), making it stiff and less able to relax and for blood to fill the heart chambers.
Investigators used the United Network of Organ Sharing Registry, a nationwide database of all U.S. transplant patients, to analyze 26,706 adult patients' clinical and survival characteristics. HCM patients comprise about 1 percent of all U.S. heart transplant cases. Yet, the survival rate is comparable to surgeries for other reasons.
Study participants were mostly white (81 percent) and male (79 percent), average age 52. HCM patients, however, tended to be younger, average age 43, and more than half were women. Nearly one-third (31 percent) of participants reported smoking, although this rate was much lower among those with HCM (17 percent). All had received a heart transplant between January 1990 and December 2004.
In the United States, HCM affects about half a million people. Its symptoms vary widely; in some cases they may be mild enough to go unnoticed, while in others they may be severe enough to cause heart failure.
Co-authors are Benjamin M. Kalsmith, M.D.; James E. Udelson, M.D.; Wenjun Li, Ph.D. and David DeNofrio, M.D. Author disclosures are on the manuscript.
Statements and conclusions of study authors published in American Heart Association scientific journals are solely those of the study authors and do not necessarily reflect the association's policy or position. The association makes no representation or guarantee as to their accuracy or reliability. The association receives funding primarily from individuals; foundations and corporations (including pharmaceutical, device manufacturers and other companies) also make donations and fund specific association programs and events. The association has strict policies to prevent these relationships from influencing the science content. Revenues from pharmaceutical and device corporations are available at www.americanheart.org/corporatefunding.
NR10 - 1113 (Circ/Maron)
Hypertrophic cardiomyopathy (HCM) Facts and Statistics:
HCM is the second most common form of heart muscle disease, is usually genetically transmitted, and comprises about 35 to 40% of cardiomyopathies in children.
HCM affects up to 500,000 people in the United States, with children under age 12 accounting for less than 10% of all cases.
Downloadable stock footage and animation available at www.americanheart.mediaroom.com. Click on "Multimedia Resources."