Exercise hemodynamic findings in patients with exertional dyspnea

To determine whether upright bicycle exercise could provide useful informat ion about disabling exertional dyspnea in the absence of severe abnormaliti es (as shown by traditional testing methods), we evaluated 13 such patients . There were 3 men and 10 women with a mean age of 49 +/- 15 (SD) years. We used pulmonary artery catheterization at rest and during upright bicycle e xercise to evaluate these patients. All patients had normal left ventricula r function except for 1, who had an ejection fraction of 45%. The mean dura tion to peak exercise was 9 +/- 6 minutes. Normal systolic pulmonary artery pressure was defined as 25 +/- 5 mmHg. Fou r patients had normal systolic pulmonary pressure, and 9 exhibited pulmonar y hypertension with exercise; In those 9 the mean mixed pulmonary venous ox ygen saturation at rest was 61% +/- 9% and fell to 32% +/- 9% at peak exerc ise. Six of the 9 patients also had some degree of resting pulmonary hypert ension that worsened with exercise: their mean pulmonary artery systolic pr essure at rest was 47 +/- 14 mmHg and rose to 75 +/- 25 mmHg at peak exerti on (P = 0.01). The other 3 patients showed no pulmonary hypertension at res t; their mean pulmonary artery systolic pressure was 27 +/- 6 mmHg. However , this level rose to 53 +/- 4 mmHg at peak exertion (P = 0.04). In this pilot study of patients with dyspnea, 9 of 13 (69%) displayed marke d pulmonary hypertension with exercise. The resting hemodynamic levels were normal in 3 (33%) of those with exercise pulmonary hypertension. We conclu de that hemodynamic data from bicycle exercise tests can provide additional information regarding the mechanisms of exertional dyspnea.