Increased aortic pulse and fractional pulse pressures in patients with cardiac syndrome X

Abstract

Background: Angina with normal coronary arteries, cardiac syndrome X, is a diagnosis of exclusion. The exact mechanism of this clinical syndrome remains unclear. Although the prognosis is as good as equal to that of the normal population, symptoms related to the syndrome largely impair quality of life. Aortic pulse and fractional pulse pressures are strong and independent indicators of the risk of coronary heart disease. An increase in these hemodynamic parameters is significantly associated with the presence of coronary artery disease in men and women.

Methods and results: We evaluated aortic pulse and fractional pulse pressures of patients with cardiac syndrome X and control subjects, and investigated the relation between the two groups. One hundred and twenty-six patients with cardiac syndrome X with a mean age of 53.1 +/- 9.5 years and 76 patients without the syndrome with a mean age of 53.1+/-11.2 years were studied consecutively from May 2004 to May 2005. Aortic systolic, diastolic, mean and pulse pressures were measured and the fractional pulse pressure was calculated (aortic pulse pressure/mean pressure). Aortic pulse and fractional pulse pressures were significantly higher in the cardiac syndrome X group than in the control group (51 +/- 13 mmHg and 43+/-9 mmHg, p < 0.001; 0.54 +/- 0.11 and 0.47 +/- 0.08, p < 0.001, respectively). All patients were classified into tertiles of aortic pulse pressure level to evaluate whether aortic pulse pressure was associated with the presence of cardiac syndrome X in the study. The multiple-adjusted odds ratio of the risk of cardiac syndrome X was 6.72 (95% CI 2.76-16.37) for tertile 2 and 29.94 (95% CI 5.59-160.44) for tertile 3 of aortic pulse pressure level compared with tertile 1. In addition, all patients were divided into two groups as lower and higher levels of aortic fractional pulse pressure. The multiple-adjusted OR of the risk of cardiac syndrome X was 4.09 (95% CI 2.05-8.15) for the higher group compared with the lower group of aortic fractional pulse pressure level.

Conclusion: Ascending aorta pulse and fractional pulse pressures are significantly associated with the presence of cardiac syndrome X and these associations are independent of age and other cardiovascular risk factors.