Global medical technology company Medtronic has demonstrated in a clinical trial that pacing the heart’s lower chambers simultaneously using a cardiac resynchronisation therapy (CRT) device will improve symptoms and quality of life in a subset of heart failure patients.

The new trial data, presented at Heart Rhythm 2013, shows a significant drop in heart failure-related symptoms for patients with atrioventricular (AV) block and left ventricular (LV) systolic dysfunction.

As part of the BLOCK HF trial, Medtronic treated patients with biventricular (BiV) pacing instead of conventional right-ventricular (RV) pacing, and observed performance at six, 12, 18 and 24 months.

University at Buffalo School of Medicine and Biomedical Sciences Department of Medicine chair and lead investigator Dr Anne Curtis said the new data reinforces the use of BiV pacing for treating patients currently indicated for permanent RV pacing with a pacemaker.

"The BLOCK HF findings have previously demonstrated that BiV pacing delays disease progression, prevents heart failure-related events and preserves cardiac function in this patient population," Curtis said.

Published in The New England Journal of Medicine, the primary trial data also showed a significant improvement in quality of life among BiV-paced patients at six and 12 months.

14% more patients improved in the BiV arm than the RV arm at six months, and more BiV patients improved under the New York Heart Association (NYHA) heart failure classification at 12 months.

BiV patients also scored an average of five points higher in quality-of-life (QoL) findings, measured by the Minnesota Living with Heart Failure questionnaire.

Medtronic Cardiac Rhythm Disease Management general manager and Heart Failure vice president Dr David Steinhaus said; "RV pacing has been considered the gold standard for decades in treating patients with AV block; however, findings from the BLOCK HF trial continue to exhibit better overall outcomes with BiV pacing via CRT devices for these patients".

Image: Therapy trial findings revealed two equally important clinical benefits: symptoms and quality-of-life improvement. Photo: Courtesy of Gregory Marcus.