346 IMPACT OF EXERCISE-INDUCED PULMONARY HYPERTENSION ON THE RIGHT VENTRICLE AND WORSENING OF CARDIOVASCULAR RISK IN HIV PATIENTS

Abstract

Abstract Background and Aim Exercise-induced pulmonary hypertension (ExPH), due to impaired pulmonary vascular and right ventricular contractile reserve on effort,predicts clinical outcomes, such as all-cause mortality or cardiovascular (CV) hospitalizations in patients with dyspnea on effort. We investigated its prognostic significance in HIV patients at risk for Pulmonary Arterial Hypertension (PAH). Methods In 52 consecutive HIV patients with either low (n=47) or intermediate probability (n=5) of PH at rest, we evaluated at time 0 and after 2 years the prognostic determinants of CV risk: onset or progression of heart failure/syncope; worsening of functional class; functional performance at the 6-Minute Walking Test and at cardiopulmonary exercise test (CPET); right atrial area; and pericardial effusion. We assigned a severity score 1-3 to each prognostic determinant, derived an overall CV risk score, and its 0-2 years change. Patients were classified as either at low, intermediate or high probability of ExPH at Stress Echocardiography (ESE), while ExPH at CPET was defined as absence of PH at rest, reduced peak VO2, VE/VCO2 >30 at anaerobic threshold, reduced O2 pulse, and ΔVO2/ΔW <9 mL/min/W. We then correlated ExPH at time 0 with clinical worsening (risk score increase >20% after 2 years). Results Right ventricle (RV) systolic function was significantly reduced in patients with ExPH compared to those without ExPH at CPET, as well as in patients with intermediate/high compared to those with low probability of ExPH at ESE, who exhibited worse values of TAPSE and FAC (p<0.001 and p=0.01, respectively). A significant higher proportion of patients with ExPH (CPET) or with intermediate/high probability of ExPH (ESE) had higher sPAP (p<0.001), mPAP (p=0.004), higher TRV (p=0.006) as well as higher right atrial area (p<0.001) and indexed right atrial volume (p=0.004). Total pulmonary vascular resistance (expressed by the ratio between TRV and velocity-time integral at the level of right ventricular outflow tract) was higher in patients with ExPH as well as in patients with intermediate/high probability of ExPH (p<0.001). Patients with intermediate/high probability of ExPH at ESE showed a trend towards clinical worsening compared to those with low probability of ExPH, albeit not statistically significant (p=0.137). In patients with low probability of ExPH, none had >20% increased CV risk score after 2 years. We found an association between higher NT-proBNP and the presence or intermediate/high probability of ExPH after 2 years (p=0.048 at CPET, p=0.033 at ESE). Conclusions At short follow-up, ExPH is associated with a worsening trend in the CV risk score which, if confirmed after longer follow-up, could contribute to better risk stratification in HIV patients.