CAN CARDIOPULMONARY EXERCISE TESTING COMBINED WITH STRESS ECHOCARDIOGRAPHY HELP TO IDENTIFY HEART FAILURE WITH PRESERVED EJECTION FRACTION IN OBESE HYPERTENSIVES?

Abstract

Objective: Background:AH and obesity are the most common pathologies that with long-term course lead to HFpEF. Although exercise intolerance and dyspnea are main symptoms of HF, they may also be caused by obesity. Recent data demonstrated that combination of cardiopulmonary exercise testing (CPX) and stress echocardiography may help to identify HFpEF at earlier time point in patients with associated diseases. Objective: to assess ability of CPX combined with diastolic stress testing to identify HFpEF in patients with AH and obesity. Design and method: We investigated 56 patients with AH and obesity aged 35–60, 22 (40%) of them also had signs of HFpEF. All patients underwent CPX in combination with diastolic stress testing. We used stepwise protocol for cycle ergometer with 8 exercise periods at progressively increasing work rate (25 watts every step). Stress echocardiography was performed at 3 levels: the 2-d exercise step (50 watts), anaerobic threshold (AT) and submaximal heart rate (HR). Results: All patients had reduced exercise capacity more severe in group with HFpEF, only 8 (36%) patients with HFpEF versus 19 (56%) without it reached submaximal HR during test. The main cause for end of test in HFpEF patients was dyspnea, in obese hypertensives without HFpEF – exertion. Peak VO2 was decreased in both groups (55–65% of predicted). This parameter was significantly higher (80–85% of predicted) in patients with obesity and normal heart function compared with HFpEF patients when predicted for height. O2 pulse at AT was slightly lower in patients with obesity and HFpEF (65% versus 78% of predicted). Ve/VCO2 slope at AT was slightly increased in both groups with significant growth in HFpEF patients (30,9 versus 33,1). Peak E/e[Combining Acute Accent] average ratio measured at AT was increased (14,7 versus 9,4) due to decrease of peak e[Combining Acute Accent] velocity (6,0 versus 11,1) in HFpEF patients. Conclusions: Both obesity and HFpEF reduce aerobic capacity and cause dyspnea. Combination of CPX and stress echocardiography helps to identify influence of HFpEF on exercise tolerance of patients with AH and obesity. Peak VO2 predicted for height (not weight), Ve/VCO2 slope measured at AT can be useful parameters.