Coronary heart disease

Martial G. Bourrassa , M.D.

Dr. Bourassa's research is directed on the diagnostic and medical, interventional or surgical treatment of the coronary heart disease.

PATHOPHYSIOLOGY, DIAGNOSTIC AND TREATMENT OF THE CORONARY DISEASE

My research interests deal primarily with the pathophysiology, diagnosis and medical, interventional, and surgical treatment of coronary artery disease. For many years, I have been interested in the pathogenesis of coronary atherosclerosis, as well as in the mechanisms of myocardial ischemia and of left ventricular dysfunction. My investigations in the diagnosis, treatment, and long-term prognosis of coronary artery disease originate, to a large extent, from my participation in large multicenter clinical trials, the results of which determine or guide modern medical practice.

With regards to my recent participation, I have been collaborating for more than 5 years to the National Heart, Lung, and Blood Institute Dynamic Registry, a registry of several thousand patients aimed at characterizing the outcome of interventional cardiology in the United States and Canada. Major publications are derived from this data bank and I have participated actively in several of them.

We have recently completed the 10-year follow-up of the patients enrolled in the Bypass Angioplasty Revascularization Investigation (BARI), a large multicenter study also supported by the National Institutes of Health. The 5-year results showed that, compared to bypass surgery, percutaneous coronary intervention did not compromise survival in patients with multi-vessel coronary disease, although re-interventions were more frequent with this approach.

However, diabetics benefited from an improved 5-year survival after bypass surgery as compared to percutaneous coronary intervention. The results at 10 years will allow us to evaluate the effects of these treatments on long-term survival, as well as their impact on health care costs and on quality of life. Currently, we are completing the enrolment phase of another large study, BARI 2D, which compares the effects of a medical regimen with strict control of the glycemia to those of coronary revascularization in diabetic patients. The results of this study will be known in a few years.

I am interested also, in the setting of previous studies in which I have been involved, especially the Coronary Artery Surgery Study (CASS) and the Studies Of Left Ventricular Dysfunction (SOLVD), to study different determinants of very long-term survival and occurrence of coronary events (15-30 years) in large patient cohorts with coronary artery disease with or without left ventricular dysfunction who were treated either medically or surgically. These patients were initially recruited at the Montreal Heart Institute and their follow-up, up to December 2004, was obtained from the Régie de l'assurance maladie du Québec et from the ministère de la Santé et des Services sociaux . The analysis of these data will be a source of several important publications.

Kip KE, Alderman EL, Bourassa MG, Brooks MM, Schwartz L, Holmes DR, Califf RM, Whitlow PL, Chaitman BR, Detre KM. Differential influence of diabetes mellitus on increased jeopardized myocardium after initial angioplasty or bypass surgery. Bypass Angioplasty Revascularization Investigation (BARI). Circulation 2002;105:1914-20.

Bourassa MG, Detre KM, Johnston JM, Vlachos H, Holubkov R. Effects of prior revascularization on outcome following percutaneous coronary intervention: NHLBI Dynamic Registry. Eur Heart J 2002;23:1546-55.

Bourassa MG, Butnaru A, Lespérance J, Tardif JC. Symptomatic myocardial bridges : Overview of ischemic mechanisms and current diagnostic and treatment strategies. J Am Coll Cardiol 2003;41:351-9.

Vermes E, Ducharme A, Bourassa MG, Lessard M, White M, Tardif JC. Enalapril reduces the incidence of diabetes in patients with chronic heart failure: insight from the SOLVD study. Circulation 2003;107:1285-90.

Vermes A, Tardif JC, Bourassa MG, Racine N, Guertin MC, White M, Ducharme A. Enalapril decreases the incidence of atrial fibrillation in patients with left ventricular dysfunction : insight from the SOLVD trials. Circulation 2003;107:2926-31.

Solymoss BC, Bourassa MG, Campeau L, Sniderman A, Marcil M, Lespérance J, Lévesque S, Varga S. Effect of increasing metabolic syndrome score on atherosclerotic risk profile and coronary artery disease angiographic severity. Am J Cardiol 2004;93:159-64.

Diaz A, Bourassa MG, Guertin MC, Tardif JC. Long-term prognostic value of resting heart rate in patients with suspected or proven coronary artery disease. Eur Heart J 2005 (in press).