Daniel Curnier

QT dynamicity: a prognostic factor for sudden cardiac death in chronic heart failure.

The aim of this study was to determine whether impaired adaptation of the QT interval to changes in heart rate predicts sudden death in patients with chronic heart failure (CHF).

CAN ANAEROBIC PERFORMANCE BE IMPROVED BY REMOTE ISCHEMIC PRECONDITIONING

Abstract Lalonde, F, and Curnier, DY. Can anaerobic performance be improved by remote ischemic preconditioning? J Strength Cond Res 29(1): 80–85, 2015—Remote ischemic preconditioning (RIPC) provides a substantial benefit for heart protection during surgery. Recent literature on RIPC reveals the potential to benefit the enhancement of sports performance as well. The aim of this study was to investigate the effect of RIPC on anaerobic performance. Seventeen healthy participants who practice regular physical activity participated in the project (9 women and 8 men, mean age 28 ± 8 years). The participants were randomly assigned to an RIPC intervention (four 5-minute cycles of ischemia reperfusion, followed by 5 minutes using a pressure cuff) or a SHAM intervention in a crossover design. After the intervention, the participants were tested for alactic anaerobic performance (6 seconds of effort) followed by a Wingate test (lactic system) on an electromagnetic cycle ergometer. The following parameters were evaluated: average power, peak power, the scale of perceived exertion, fatigue index (in watt per second), peak power (in Watt), time to reach peak power (in seconds), minimum power (in Watt), the average power-to-weight ratio (in watt per kilogram), and the maximum power-to-weight ratio (in watt per kilogram). The peak power for the Wingate test is 794 W for RIPC and 777 W for the control group (p = 0.208). The average power is 529 W (RIPC) vs. 520 W for controls (p = 0.079). Perceived effort for RIPC is 9/10 on the Borg scale vs. 10/10 for the control group (p = 0.123). Remote ischemic preconditioning does not offer any significant benefits for anaerobic performance.

Effects of Short-term Exercise and Exercise Training on Cognitive Function Among Patients With Cardiac Disease

PURPOSE A number of studies have investigated the effect of physical activity on cognitive performance in healthy subjects although no consensus in results has been established. In patients with cardiac disease that has been associated with cognitive impairment, research regarding improvement in cognition function assumes a clinical interest. We assessed the effect of both acute exercise and aerobic training on cognitive function in patients with coronary artery disease and heart failure who participated in cardiac rehabilitation (CR). METHODS Twenty-four men (mean age = 51.6 ± 6.5 years) completed 2 experimental sessions, before (S1) and after exercise training (S2). During each session, participants underwent cognitive evaluations at rest and during exercise on a cycloergometer at 30% of maximal power. Two types of evaluations were used, an exclusively cognitive test (COG, such as arithmetic test, memory test) and a tracking task (TRAC) including motor precision. RESULTS At S1, no significant difference appeared between rest and acute exercise for COG score (31.5 ± 9.5 vs 32.2 ± 10.5; ns). In contrast, acute exercise significantly improved TRAC performance (149 ± 54 vs 140 ± 44; P < .05). At S2, COG score improved with exercise (35.5 ± 10.6 vs 40 ± 10.8; P ≤ .001) but TRAC score remained unchanged (138 ± 50 vs 134 ± 42; ns). Concerning the impact of exercise (Δ%), a significant difference was observed for COG (0.03 [−0.03 to 0.11] vs 0.14 [−0.01 to 0.24]; P < .05), before and after training, respectively, but not for TRAC. CONCLUSIONS Limited data are available concerning the effect of acute exercise and exercise training on cognitive function in patients with cardiac disease. This study provides evidence for the importance of CR in improving cognitive function.

Exercise-induced ischemic preconditioning and the potential application to cardiac rehabilitation: a systematic review.

Exercise-induced ischemic preconditioning (IPC) can be assessed by the results of the second of sequential exercise tests. Exercise-induced IPC is quantified by using the time to 1-mm ST-segment depression, the rate-pressure product at 1-mm ST-segment depression, the maximal ST-segment depression, and the rate-pressure product at the peak of exercise. Few studies reported whether exercise-induced IPC could be used in cardiovascular rehabilitation. A systematic review of the literature limited to human studies was performed using electronic databases, and the main key words were ischemic preconditioning, warm-up phenomenon, and exercise. After careful review, 38 articles were included in the systematic review. This review summarizes the molecular pathways of IPC and describes the first window of protection induced by sequential exercise tests, as well as the effect of medication on exercise-induced IPC. A section on the exercise protocol, mode of exercise, and intensity provides understanding as to what is needed for clinicians to induce IPC with sequential stress tests. The final section of the review is a discussion of the potential use of exercise-induced IPC in a cardiovascular rehabilitation setting. Even if exercise-induced IPC is a well-documented phenomenon, additional studies are needed in order to more fully understand its use in rehabilitation.

Preventive fraction of physical fitness on risk factors in cardiac patients: Retrospective epidemiological study

AIM To quantify the preventive fraction of physical fitness on the risk factors in patients with cardiovascular diseases (CVDs). METHODS A total of 249 subjects (205 men and 44 women) suffering from CVD were categorized into four groups, according to their percentage of physical fitness. We calculated the odds ratio to obtain the preventive fraction in order to evaluate the impact of the physical fitness level on the risk factors (i.e., abdominal obesity, depression, diabetes, dyslipidemia, hypertension, obesity, overweight and smoking). RESULTS It is observed that a normal physical fitness level is sufficient to induce a preventive action on abdominal obesity (38%), diabetes (12%), hypertension (33%), obesity (12%) and overweight (11%). Also, the preventive fraction increases with the level of physical fitness, in particular for hypertension (36%) and overweight (16%). A high physical fitness level does not necessarily induce a preventive action in most risk factors, excluding depression. CONCLUSION This is the first study which demonstrates that reaching a normal physical fitness level is enough to induce a protection for some risk factors, despite having a CVD.