A randomised trial comparing the effect of exercise training and weight loss on microvascular function in coronary artery disease

• Published in: International journal of cardiology 2015-04, Vol.185, p.229-235
• Main Authors: Olsen, Rasmus Huan, Pedersen, Lene Rørholm, Jürs, Anders, Snoer, Martin, Haugaard, Steen B, Prescott, Eva
• Format: Article
• Language: English
• Subjects: Aged; Body Mass Index; Caloric restriction; Cardiovascular; Coronary artery disease; Coronary Artery Disease - complications; Coronary Artery Disease - physiopathology; Coronary Artery Disease - rehabilitation; Coronary Circulation - physiology; Coronary flow reserve; Coronary microvascular function; Echocardiography, Doppler - methods; Exercise - physiology; Exercise Therapy - methods; Exercise training; Female; Follow-Up Studies; Humans; Male; Microcirculation - physiology; Middle Aged; Obesity - complications; Obesity - rehabilitation; Prognosis; Regional Blood Flow - physiology; Time Factors; Weight Loss
• ISSN: 0167-5273; 1874-1754
• DOI: 10.1016/j.ijcard.2015.03.118

Abstract Background Coronary microvascular function is associated with outcome and is reduced in coronary artery disease (CAD) and obesity. We compared the effect of aerobic interval training (AIT) and weight loss on coronary flow reserve (CFR) and peripheral vascular function in revascularised obese CAD patients. Methods and results Seventy non-diabetic patients (BMI 28–40 kg×m − 2 , age 45–75 years) were randomised to 12 weeks' AIT (three weekly sessions lasting 38 min with ≈ 16 min at 85–90% of VO2 peak) or low energy diet (LED, 800–1000 kcal/day). Per protocol adherence was defined by training-attendance ≥ 60% and weight loss ≥ 5%, respectively. CFR was assessed by Doppler echocardiography of the LAD. Peripheral vascular function was assessed by arterial tonometry as reactive hyperaemia index (RHI) and augmentation index. Most participants had impaired CFR with a mean CFR of 2.38 (SD 0.59). Twenty-six AIT and 24 LED participants completed the study per protocol with valid CFR measurements. AIT resulted in a 10.4% improvement in VO2 peak and LED in a 10.6% weight loss (between group differences both P < 0.001). CFR increased by 0.26 (95%CI 0.04;0.48) after AIT and by 0.39 (95%CI 0.13;0.65) after LED without significant between-group difference (− 0.13 (95%CI − 0.45;0.20)). RHI and augmentation index remained unchanged after both interventions ( P > 0.50). Intention-to-treat analyses showed similar results. Conclusions 12 weeks' AIT and LED increased CFR by comparable magnitude; thus both interventions might impact prognosis of CAD through improvement of coronary microvascular function. Clinical Trial Registration URL: http://www.clinicaltrials.gov . Unique identifier: NCT01724567.