Abstract 3597: Impact of Increase in Left Ventricular Filling Pressure During Exercise on Clinical Outcome in Patients With Exercise-induced Pulmonary Hypertension and Preserved Left Ventricular Ejection Fraction
Background: Exercise-induced pulmonary hypertension (PH) is common even in subjects with preserved left ventricular (LV) ejection fraction. Although increase in LV filling pressure during exercise would be an important contributor, its association on clinical outcome has not been studied. We hypothesized that exercise-induced PH associated with increase in LV filling pressure during exercise would predict poorer outcome in patients with preserved LV ejection fraction.
Methods: 1,401 consecutive subjects underwent a graded, symptom-limited, supine bicycle exercise echocardiography. The patients with LV ejection fraction<50%, subjects whose tricuspid regurgitation (TR) velocity or E/E′ could not be measured either at rest or during exercise were excluded. Among the remaining 525 subjects, 184(34%) subjects showed exercise-induced PH, defined as pulmonary artery systolic pressure >50 mmHg at 50W of exercise. They were classified according to E/E′ at 50W of exercise; Group I (n=131), E/E′<15, Group II (n=53), E/E′≥15. The end-point was a composite of major cardiovascular events and any cause of deaths.
Results: During a median follow up of 32(range 6–78) months, 16(9.6%) had adverse events. The 5-year event free survival rates were 95% and 75%, respectively. The independent predictor of adverse events was E/E′ at 50W (p<0.001, HR 1.15, 95% CI 1.07–1.24) in patients with exercise-induced PH.
Conclusion: In patients with exercise-induced PH, the presence of increase in LV filling pressure with exercise portends poorer clinical outcome when compared with those with exercise-induced PH but not associated with increase in LV filling pressure during exercise.