Effect of metoprolol CR/XL on pulmonary artery pressure in chronic heart failure patients assessed by an implanted ultrasonic device with special emphasis on diurnal variation and exercise capacity

Objective: We evaluated the impact of Metoprolol CR/XL on the diurnal and exercise induced variation on Pulmonary Artery Pressure (PAP) in patients with Chronic Heart Failure (CHF) by implanted ultrasonic device. Background: Metoprolol produces haemodynamic and clinical benefits in patients with chronic heart failure and improves survival rate. There is limited information about their effect on PAP, its diurnal and exercise induced variation in heart failure. This study evaluates the diurnal variation and effects of exercise capacity on PAP and impact of Metoprolol CR/XL (MXL) on these variations on PAP in CHF patients. Methods: In this first-in-man study, ten NYHA class III/IV patients were implanted with an ultrasonic pressuremonitoring device, followed a month later by loading with MXL 25 mg/day and uptitrated every two weeks to 200 mg/day. PAP was measured at each follow up. Diurnal variation was evaluated at baseline (no MXL), 100, and 200 mg/day MXL. Treadmill Test (TMT) was performed before and at each uptitration. Echocardiography was performed at one year. Results: Uptitrating MXL caused a slight initial rise in PAP, followed by a subsequent decrease on reaching 200 mg/day dose. One patient showed repeated symptomatic rise in PAP indicating MXL intolerance and was discontinued from the uptitration. The nocturnal rise in PAP at baseline was reduced on reaching 200 mg/day MXL dose. Uptitrating MXL to 200mg/day improved exercise time and metabolic equivalent tasks ( METS) with no significant change in post TMT PAP. Ejection fraction also improved at one-year follow-up. Conclusions: PAP increases post exercise and diurnally in CHF patients. Slow and careful uptitration of MXL with simultaneous non-invasive monitoring of PAP may benefit in nocturnal rise and exercise capacity in CHF patients.