PURPOSE:The prevalence of exercise-induced pulmonary hypertension (PH) and its associated characteristics and significance are not known.
METHODS:A total of 1,053 patients (pts) with normal (<35 mm Hg) Doppler-derived right ventricular systolic pressures (RVSP) underwent clinically indicated treadmill exercise echocardiography. Exclusions were age <18 years, more than mild valvular disease, history of coronary artery disease, left ventricular (LV) ejection fraction <50%, and atrial fibrillation/flutter. Exercise-induced pulmonary hypertension (Ex-PH) was defined as an RVSP>50 mmHg in immediate recovery.
RESULTS:There was Ex-PH in 93 pts (8.8%). Pts with ex-PH were older (68±11 vs. 60±12, p<0.0001). had higher resting systemic blood pressure (BP) (systolic BP 134±21 vs 125±18, p<0.0001), increased vascular stiffness (pulse pressure 59±16 vs. 50± 15 mmHg), were more likely to be have smoked (56% vs 40%, p=0.0007), and more often had markers of LV diastolic dysfunction (E/e’ >8: 41% vs 24%, p<0.005 and left atrial enlargement: 59% vs 46%, p<0.01). Exercise capacity was, on average, lower in pts with Ex-PH (7.4±3 mins vs 8.6±3 mins, p<0.0001), figure. The occurrence of Ex-PH was associated with elevated LV filling pressures with exercise (stress E/e’ >13 in 23% vs 14%, p<0.05) and evidence of ischemia on the stress echo (25% vs 15%, p<0.01). The development of Ex-PH was associated with the extent and severity of exercise-related LV dysfunction; 4.4% of patients with Ex-PH had a wall motion score index >2 vs. 0.6% of those with normal pressures (p<0.0005), and 16% of patients with Ex-PH had an abnormal response of the LV end-systolic size to stress (no change or an increase) compared to 7% (p<0.0002).
CONCLUSION:Ex-PH occurred in 8.8% of pts undergoing exercise echocardiography. Ex-PH is associated with an impaired exercise capacity and can be partly explained by exercise-related LV systolic and/or diastolic dysfunction.
CLINICAL IMPLICATIONS:Assessment for exercise related changes in RVSP can be incorporated into a treadmill stress echocardiogram with Ex-PH potentially responsible for symptoms of exertional dyspnea.
DISCLOSURE:Garvan Kane, No Financial Disclosure Information; No Product/Research Disclosure Information