Aerobic Interval vs. Continuous Training in Patients with Coronary Artery Disease or Heart Failure: An Updated Systematic Review and Meta-Analysis with a Focus on Secondary Outcomes.

BACKGROUND: In a previous meta-analysis including nine trials comparing aerobic interval training with aerobic continuous training in patients with coronary artery disease, we found a significant difference in peak oxygen uptake favoring aerobic interval training. OBJECTIVE: The objective of this study was to (1) update the original meta-analysis focussing on peak oxygen uptake and (2) evaluate the effect on secondary outcomes. METHODS: We conducted a systematic review with a meta-analysis by searching PubMed and SPORTDiscus databases up to March 2017. We included randomized trials comparing aerobic interval training and aerobic continuous training in patients with coronary artery disease or chronic heart failure. The primary outcome was change in peak oxygen uptake. Secondary outcomes included cardiorespiratory parameters, cardiovascular risk factors, cardiac and vascular function, and quality of life. RESULTS: Twenty-four papers were identified (n = 1080; mean age 60.7 ± 10.7 years). Aerobic interval training resulted in a higher increase in peak oxygen uptake compared with aerobic continuous training in all patients (1.40 mL/kg/min; p < 0.001), and in the subgroups of patients with coronary artery disease (1.25 mL/kg/min; p = 0.001) and patients with chronic heart failure with reduced ejection fraction (1.46 mL/kg/min; p = 0.03). Moreover, a larger increase of the first ventilatory threshold and peak heart rate was observed after aerobic interval training in all patients. Other cardiorespiratory parameters, cardiovascular risk factors, and quality of life were equally affected. CONCLUSION: This meta-analysis adds further evidence to the clinically significant larger increase in peak oxygen uptake following aerobic interval training vs. aerobic continuous training in patients with coronary artery disease and chronic heart failure. More well-designed randomized controlled trials are needed to establish the safety of aerobic interval training and the sustainability of the training response over longer periods.

Predictive value of Type D personality for impaired endothelial function in patients with coronary artery disease.

BACKGROUND: Type D personality (high negative affectivity and social inhibition) is associated with cardiovascular events and coronary plaque severity. Whether Type D is also related to functional vasomotion abnormalities is unknown. We examined concurrent and predictive associations of Type D with endothelial dysfunction in patients with coronary artery disease (CAD). METHODS: At baseline, 180 CAD patients (90% men; M = 58.0 years) completed Type D (DS14) and depression scales, and entered a 12-week exercise program. Flow-mediated dilation (FMD) of the brachial artery and circulating CD34+/KDR+/CD45+dim endothelial progenitor cells (EPCs) were assessed at baseline, 3 months, and 12 months. Logistic regression and linear mixed models were used to analyze endothelial function. RESULTS: Type D personality was associated with decreased FMD across baseline, 3 months, and 12 months (mixed model analysis, p = 0.04), after adjustment for clinical characteristics, exercise training and depression. There was no significant association between Type D and decreased EPCs (p = 0.07). Age and smoking were other significant correlates of FMD and EPCs. Using a FMD <5.5% cut-off, Type D patients more often had endothelial dysfunction at baseline (24/37 = 65%) than non-Type Ds (63/143 = 44%); OR = 3.03, 95% CI 1.04-8.80. This significant Type D effect was confirmed in prospective analyses of endothelial dysfunction at 12 months (OR = 3.43, 95% CI 1.01-11.64), and in subgroup analyses of male patients. CONCLUSIONS: Type D personality was associated with impaired endothelial function in men with CAD. This association was robust across time, independent from depressive symptoms, and supports the notion that Type D has an adverse effect on cardiovascular health in patients with CAD.

Test-Retest Reliability of Maximal and Submaximal Gas Exchange Variables in Patients With Coronary Artery Disease.

PURPOSE: Gas exchange variables derived from cardiopulmonary exercise tests (CPETs) need to be reliable for evaluating interventions and clinical decision making. Whereas peak oxygen uptake ((Equation is included in full-text article.)O2) has shown to be a highly reliable parameter in patients with coronary artery disease (CAD), little is known about the reproducibility of these parameters in patients with CAD. Therefore, the purpose of this study was to confirm the reliability of peak (Equation is included in full-text article.)O2 and to investigate the reliability of submaximal CPET variables in patients with CAD. METHODS: Eighty-five patients with CAD (57.6 ± 8.5 years; 79 males) performed 2 CPETs within 10 days before starting a rehabilitation program. Reliability of peak and submaximal exercise variables was assessed by using intraclass correlation coefficients (ICC), coefficients of variation, Pearson correlation coefficients, paired t tests, and Bland-Altman plots. RESULTS: Maximal and submaximal exercise parameters showed adequate reliability. Overall, there was a good correlation across both testing occasions (r = 0.63-0.95; P < .05 for all). Peak (Equation is included in full-text article.)O2 (ICC, 0.95; 95% CI, 0.92-0.97) demonstrated excellent reliability. Of the submaximal exercise variables, oxygen uptake efficiency slope (OUES) was as reliable as peak (Equation is included in full-text article.)O2 (ICC, 0.97; 95% CI, 0.95-0.98). The ventilation/carbon dioxide production ((Equation is included in full-text article.)E/(Equation is included in full-text article.)CO2) slope showed very good test-retest reliability (ICC, 0.87; 95% CI, 0.80-0.91) and the (Equation is included in full-text article.)O2/work rate slope showed good reliability (ICC, 0.76; 95% CI, 0.64-0.85). CONCLUSIONS: Both peak (Equation is included in full-text article.)O2 and OUES show excellent test-retest reliability. Accordingly, in the case of no or unreliable peak (Equation is included in full-text article.)O2 data, we suggest using OUES to evaluate cardiorespiratory fitness in patients with CAD.