Abstract The primary chronic symptom in patients with clinically stable heart failure (HF) is reduced exercise tolerance, measured as decreased peak aerobic power (peak oxygen consumption V o2 ), and ...is associated with reduced quality of life and survival. Exercise-based cardiac rehabilitation (EBCR) is a safe and effective intervention to improve peak V o2 , muscle strength, physical functional performance, and quality of life and is associated with a reduction in overall and HF-specific hospitalization in clinically stable patients with HF. Despite these salient benefits, fewer than one-tenth of eligible patients with HF are referred for EBCR after hospitalization. In this review, selection for and timing of EBCR for patients with HF, as well as exercise prescription guidelines with special emphasis on the optimal exercise training intensity to improve peak Vo2 , are discussed.
Abstract Prompt administration of high quality cardiopulmonary resuscitation (CPR) is key determinant of survival from cardiac arrest. Strategies to improve CPR quality at point of care could improve ...resuscitation outcomes. We tested whether a low cost and scalable mobile phone or smart watch based solution could provide accurate measures of compression depth and rate during simulated CPR. Fifty healthcare providers (57% ICU nurses) performed simulated CPR on a calibrated training manikin (Resusci-Anne, Laerdl) while wearing both devices. Subjects received real-time audiovisual feedback from each device sequentially. Primary outcome was accuracy of compression depth and rate compared to the calibrated training manikin Secondary outcome was improvement in CPR quality as defined by meeting both guideline recommend compression depth (5 – 6 cm) and rate (100 -120/minute). Compared to the training manikin, typical error for compression depth was < 5 mm (smart-phone 4.6 mm; 95% CI 4.1 – 5.3 mm; smart-watch 4.3 mm; 3.8 – 5.0 mm). Compression rates were similarly accurate (smart-phone Pearson R=0.93; smart-watch R=0.97). There was no difference in improved CPR quality defined as number of sessions meeting both guideline recommended compression depth (50-60 mm) and rate (100-120 compressions/minute) with mobile device feedback (60% vs 50%; p=0.3). Sessions that did not meet guideline recommendations failed primarily because of inadequate compression depth (46 ± 2 mm). In conclusion, a mobile device application guided CPR can accurately track compression depth and rate during simulation in a practice environment in accordance with resuscitation guidelines.
Athletes represent the extremes of human performance. Many of their remarkable abilities stem from a cardiovascular system that has adapted to meet the metabolic needs of exercising muscle. A large ...and compliant heart is a hallmark feature of athletes who engage in highly aerobic events. Despite high fitness levels, athletes may present with symptoms that limit performance. Understanding and dissecting these limitations requires a strong background in sports science and the factors that determine sports capabilities. This article reviews the basic principles of exercise physiology, cardiovascular adaptations unique to the "athlete's heart," and the utility of exercise testing in athletes.
