NEW YORK – Dialysis patients who underwent sessions up to six times a week instead of the conventional three showed improvement in their heart condition and told researchers they felt better, a study found.

More frequent dialysis resulted in less damage to patients’ left ventricular heart muscles, which tend to thicken and enlarge when there’s too much fluid in the body, said Glenn Chertow, chief of nephrology at Stanford University School of Medicine in Stanford, Calif. That should “translate into better heart function,” he said.

About 400,000 Americans undergo dialysis, with the annual cost of treating end-stage kidney disease sufferers reaching $75,000 to $100,000 per patient, Chertow said. The study was reported Saturday at the American Society of Nephrology meeting in Denver.

More sessions may be costlier and inconvenient for patients.

It also may prove to be a challenge for companies that provide dialysis services, said Alan Kliger, a clinical professor of medicine at Yale University and senior author of the study.