Therapy urged for heart failure subtype

WASHINGTON, Nov. 18 (UPI) -- A type of heart failure patient for whom traditional treatments don't work is a critical area for study, researchers said.

"The group of patients we have identified have all the symptoms of diastolic heart failure but their hearts fill adequately," David Kass, study co-author and the Abraham and Virginia Weiss Professor of Cardiology at Johns Hopkins Medical Center, told United Press International.

In most diastolic heart failure patients, the heart has become so stiff that it can't expand to hold an adequate amount of blood, so the body, including the heart muscle itself, gets an insufficient supply, he said.

"What we discovered is that, unlike healthy people, their heart rates don't go up in response to exercise and the walls of their arteries don't relax to accept increased blood flow. Even though their hearts are strong enough to pump well and elastic enough to expand when necessary, their low heart rates and tight arteries keep enough blood from getting to the rest of the body."

Kass said that beta blockers, the standard treatment for diastolic heart failure, slow the heart down so it has more time to fill and its stiff walls can expand gradually, but this therapy is contraindicated for the patients he is studying.

"The group in question is definitely not served by beta blockers," said Barry Borlaug, a postdoctoral fellow in Hopkins' Division of Cardiology and co-author of the study. "They need medications that will help their hearts speed up in response to exercise and other drugs to get their arteries to relax. There aren't many medications out there that will do this so, we need to address the problem right away and work collaboratively to solve it."

William C. Little, chief of cardiology at Wake Forest University School of Medicine in Winston-Salem, North Carolina, told UPI that he and his colleague, Dalane Kitzman, had also studied the problem and agreed that the use of beta blockers was not optimal treatment for these patients.

"Diastolic heart failure is an important and understudied condition," Little said. "The Hopkins work provides new insight and is a valuable advance, but I think the fact that the control group in their study had some of the same problems as the experimental group instead of being healthy means that more work must be done before their observations can supersede previous results."

Kass and Borlaug said they were eager to expand their work and a randomized multicenter trial of several medications was being actively discussed. But the researchers said they need a grant from the National Institutes of Health to proceed since the medications involved were generic and drug companies probably would not participate.

"Patients with this condition have problems doing something as simple as getting dressed in the morning or washing dishes. We are anxious to move our research forward and learn how to help them," Borlaug concluded.

Kass noted that most heart failure patients, or about 60 percent, have the disease type known systolic heart failure where the patient's heart isn't strong enough to push blood to the rest of th body.