Haemodynamic responses to exercise stress test in postmenopausal women with coronary artery disease

Coronary artery disease is the leading cause of death and disability in women. The incidence of coronary artery disease increases sharply after menopause. Coronary artery disease results from imbalance between myocardial oxygen supply and oxygen demand of the heart. Myocardial oxygen consumption is a helpful indicator of the response of the coronary circulation to the myocardial oxygen demand. Myocardial oxygen consumption is calculated by indirect methods like Stroke's work, Fick's principle, tension time index and rate pressure product. Rate pressure product is a major determinant of cardiac oxygen consumption. It is the product of heart rate with systolic blood pressure. It indicates that adequate stress was achieved and is an important indicator of ventricular function. It increases progressively with exercise. Peak rate pressure product is the rate pressure product at peak of exercise. Peak rate pressure product gives an accurate reflection of the myocardial oxygen demand and myocardial workload. The higher the peak rate pressure product, more will be the myocardial oxygen consumption. The ability to reach higher peak rate pressure product is associated with more adequate coronary perfusion. Thus the low value of peak rate pressure product suggests significant compromise of coronary perfusion and decreased left ventricular function. In the present study effect of exercise on haemodynamic parameters of postmenopausal women without coronary artery disease and postmenopausal women with coronary artery disease were compared. The percentage increase in systolic blood pressure was significantly more in postmenopausal women without coronary artery disease. The peak rate pressure product was significantly more in postmenopausal women without coronary artery disease (28.04 +/- 0.8293 mm of Hg beats / minute x 10(3)) as compared to postmenopausal women with coronary artery disease (25.14+/- 0.8993 mm of Hg beats/ minute x 10(3)) indicating more compromised coronary perfusion in postmenopausal woman with coronary artery disease.