An extract from the leaves of the crataegus, or hawthorn tree, appeared to be safe and extended the lives of some patients with congestive heart failure who were already receiving other medicinal treatment by an average of four months, a study found.
Results of the 2,681-patient, two-year clinical trial that tested the extract known as WS 1442 against a placebo, were presented Tuesday at the American College of Cardiology scientific meeting here.
Patients taking the extract showed a significant survival benefit at six months and at 18 months during the study, but by the end of the two years there was no meaningful difference in death rates between the two groups, so the study failed to meet its primary goal, researchers said.
The extract from the crataegus tree, which has its origins in Europe and Ireland and grows throughout North America, is a natural antioxidant that has been used in parts of Europe to treat heart failure, a condition in which the heart is no longer able to pump enough blood to the body's other organs.
Dr. Christian Holubarsh, the study's lead investigator, said hawthorn has been used for centuries in traditional European medicine. He said this study confirmed the safety of the extract, if not its ability to extend lives, despite the mortality difference seen at 18 months -- a secondary end point of the trial.
"This study cannot prove that crataegus postpones death in these patients but the data are promising and you can give it to people safely," said Holubarsh, from the Median Kliniken Hospitals in Bad Krozingen, Germany.
Patients in the trial had severely impaired left ventricular function, indicating advanced congestive heart failure.
The primary goal of the study was time to first cardiac event, defined as sudden cardiac death, death due to progressive heart failure, fatal and nonfatal heart attacks or hospitalization due to heart failure.
Researchers found that patients who received the extract had a 20 percent reduction in cardiac-related deaths, which translated into four months of added survival time, during the first 18 months of the study.
"It postpones death of cardiac cause after 18 months and sudden cardiac death in an important subgroup of patients," Holubarsh said.
There is an effect on coronary outcomes, Holubarsh said. But because the trial missed on its primary goal, he said further studies of the herbal medicine are necessary.