Haemodynamic response to exercise in patients with chest pain and normal coronary angiograms

A series of 42 patients with chest pain but normal coronary angiograms and normal haemodynamics at rest were prospectively classified as typical angina (group 1, N = 9) or atypical angina (group 2, N = 16) or non-anginal chest pain (group 3, N = 17). All patients underwent radionuclide ventriculography and measurement of pulmonary artery pressure at rest and during maximum exercise. Comparison of data during exercise revealed significantly higher (P less than 0.025) left ventricular filing pressures as reflected by the diastolic pulmonary artery pressure in group 1 (29 +/- 5 mmHg) than in both group 2 (22 +/- 6 mmHg) and group 3 (22 +/- 5 mmHg). The rest-to-exercise change in left ventricular ejection fraction was variable and not significant in group 1 (62 +/- 6% vs 63 +/- 14%). By contrast, both group 2 and group 3 had significant increases (63 +/- 6% vs 69 +/- 10%, P less than 0.02 and 63 +/- 5% vs 68 +/- 5%, P less than 0.01). The classification as 'typical angina' was predictive of an abnormal (greater than 25 mmHg) filling-pressure response to stress. The positive and negative predictive values were 78% and 70%, respectively. The clinical classification was not a predictor of an abnormal (delta less than 5%) ejection-fraction response. No correlation between radionuclide and filling-pressure data could be established. The data suggest that the majority of patients assigned to group 1 manifested an impaired left ventricular function with exercise. This was primarily related to abnormalities in diastolic filling while the systolic performance was not consistently depressed.