RIGHT CORONARY-ARTERY STENOSIS IS ASSOCIATED WITH IMPAIRED CARDIAC ENDOCRINE FUNCTION DURING EXERCISE

Aims Resting plasma levels of atrial natriuretic peptide and B-type na triuretic peptide rise with left ventricular dysfunction, but little i s known about effects of cardiac ischaemia on atrial natriuretic pepti de and B-type natriuretic peptide levels during exercise. We investiga ted exercise levels of atrial natriuretic peptide and B-type natriuret ic peptide in patients with suspected angina to determine whether thes e measurements could improve non-invasive assessment of coronary disea se severity. Methods and results One hundred patients performed an exe rcise test (Bruce protocol) within 2 weeks of coronary angiography. Pl asma levels of atrial natriuretic peptide and B-type natriuretic pepti de were measured at rest and at peak exercise. Multivariate regression analysis was used to assess effects of age, sex, coronary anatomy, ex ercise time and ventricular function on atrial natriuretic peptide and B-type natriuretic peptide levels. Increasing age and female sex were significantly associated with higher resting atrial natriuretic pepti de levels; age alone was associated with higher exercise atrial natriu retic peptide levels. As expected, left ventricular end-diastolic pres sure and disease of left anterior descending and circumflex coronary a rteries were associated with increased resting B-type natriuretic pept ide levels. However, the usual rise in B-type natriuretic peptide leve ls during exercise was independently reduced by disease of the right c oronary artery. Conclusion This paradoxical effect of right coronary a rtery disease limits the value of natriuretic peptide measurements as predictors of coronary disease severity. Impaired release of B-type na triuretic peptide may reduce exercise tolerance in patients with right coronary artery disease.