MedicalResearch.com Interview with:
Dr. Gregory M. Marcus MD
Gregory M Marcus, MD, MAS, FACC, FAHA, FHRS
Director of Clinical Research
Division of Cardiology
Endowed Professor of Atrial Fibrillation Research
University of California, San Francisco
MedicalResearch.com: What is the background for this study? What are the main findings?
Conduction system disease, or blockages in the electrically system (as opposed to blockages in the blood vessels, of which most are well-aware), is a common condition responsible for both heart failure in many patients as well as the need for pacemaker implantation. Although treatments for the disease are available, there are no known means to prevent it. This is important as the primary treatment, a pacemaker, can itself cause problems (including procedural complications, a long-term risk of infection with repeated battery changes, and even a greater risk of heart failure). In addition, predictors of what types of individuals are at risk for developing conduction disease has largely remained unknown.
Based on the fact that the majority of conduction disease is due to fibrosis, or scarring, of the conduction system, we sought to test the hypothesis that a common drug for high blood pressure with anti-fibrotic properties, Lisinopril, might reduce the risk of new conduction system disease. We took advantage of the fact that more than 20,000 patients with hypertension were randomized to three common high blood pressure drugs that work via different mechanisms in the ALLHAT trial: Lisinopril, amlodipine, and chlorthalidone. We found that participants randomly assigned to Lisinopril were statistically significantly less likely to develop conduction disease. In addition, our analyses revealed several risk factors for the development of conduction disease: older age, male sex, diabetes, smoking, a thicker heart, and white race (compared to black race).