Exercise-Induced Abnormal Increase of Systolic Pulmonary Artery Pressure in Adult Patients With Sickle Cell Anemia: An Exercise Stress Echocardiography Study

Background: Pulmonary hypertension (PH) at rest is a risk factor for death in patients with sickle cell anemia (SCA). Exercise echocardiography (EE) can detect latent PH. We sought to investigate the occurrence of exercise-induced abnormal response of systolic pulmonary artery pressure (SPAP) in adult patients with SCA and normal SPAP at rest, and to identify the independent predictors of this abnormal response. Methods and Results: Forty-four adult patients with SCA and normal SPAP at rest (tricuspid regurgitant jet flow velocity [TRV] < 2.5 m/sec) were studied and divided into 2 groups: exhibiting normal SPAP after treadmill EE (TRV <= 2.7 m/sec) (G1), and exhibiting abnormal exercise-induced increase of SPAP (TRV > 2.7 m/sec) (G2). TRV cutoff points at rest and during EE were based on data from healthy-matched control subjects. Abnormal response of SPAP with exercise occurred in 57% of the sample (G2), with mean TRV level of 3.39 +/- 0.41 m/sec (range 2.8-4.5 m/sec), significantly higher than those of G1 (2.29 +/- 0.25 m/sec, range 2.0-2.7 m/sec; P < 0.001). Multivariate analysis identified TRV value in resting conditions >= 2.25 m/sec (P < 0.05), left atrial volume index >= 41 mL/m(2) (P < 0.05), and a E/e'-waves ratio >= 6.3 (P < 0.05) as independent predictors of exercise-induced increase of SPAP. Conclusion: We concluded that adult patients with SCA and normal SPAP at rest may exhibit abnormal exercise-induced increase in SPAP, which was independently related to resting TRV levels, and indices of diastolic impairment and left ventricular filling pressure.