Aerobic interval training in patients with heart failure and an implantable cardioverter defibrillator: a controlled study evaluating feasibility and effect.

BACKGROUND: Aerobic interval training (AIT) has been shown to be superior to moderate continuous exercise training in improving exercise capacity and endothelial function in patients with both coronary artery disease and heart failure (HF). The objective of this study was to evaluate this training modality in patients with HF and an implantable cardioverter defibrillator (ICD) with regard to feasibility, safety, and effect. METHODS: We prospectively included 38 patients with an ICD: 26 patients participated in an AIT programme for 3 months, while 12 patients served as controls. At baseline and 12-week follow up, patients were assessed with a maximal ergospirometry stress test, echocardiography, endothelial function testing, and ICD interrogation. RESULTS: No exercise-related adverse events occurred during or soon after the training sessions. ICD interrogation revealed no sustained arrhythmias, antitachycardia pacing, or ICD discharge related to exercise sessions. The AIT programme led to a significant increase in peak oxygen uptake, cycle ergometer workload, and endothelial function compared to the control group. The training programme was safe and not associated with any adverse events or ICD-related complications. CONCLUSIONS: An AIT programme is feasible and seems safe in a well-treated, stable ICD population. Further, AIT for 3 months results in significantly increased aerobic capacity and endothelial function in this population.

Increased confidence to engage in physical exertion: older ICD recipients' experiences of participating in an exercise training programme.

BACKGROUND: Research suggests that exercise training (ET) programmes may improve both physical and psychosocial functioning in implantable cardioverter defibrillator (ICD) recipients. Most of this research has been conducted by means of quantitative methods. However, knowledge of older ICD recipients' experiences of participating in such programmes is sparse. There is thus a need for more detailed qualitative data from the perspective of older patients. AIM: To describe older ICD recipients' experiences of participating in an ET programme. METHODS: A qualitative design with semistructured interviews involving 12 older ICD recipients who had participated in a 3-month ET programme. Mini-disc recordings of the interviews were transcribed verbatim and analysed using content analysis. RESULTS: The analysis revealed two major themes: (1) 'increased confidence to engage in physical exertion'; and (2) 'increased satisfaction with life'. The first theme is illustrated by three subthemes: 'perceived support from physiotherapists', 'perceiving the heart rate monitor as a motivation to exercise', and 'perceiving peers as motivators for enjoyment and making the effort to exercise'. The second theme was illustrated by the following subthemes: 'perceived psychosocial benefits', 'perceived physical benefits', and 'exercise as a new health habit'. CONCLUSION: The findings indicate that exercising in a cardiac rehabilitation centre together with peers and supervised by skilled healthcare professionals may increase motivation to exert oneself, leading to emotional and physical benefits as well as a more social and active lifestyle for older ICD recipients.

Inflammatory response to percutaneous coronary intervention in stable coronary artery disease.

Percutaneous coronary intervention (PCI) can be regarded as a model for mechanical induced plaque rupture. The objective of this study was to evaluate the inflammatory response to PCI in stable coronary artery disease (CAD) by analysing plasma levels of a wide range of inflammatory mediators. Consecutively, we included 36 patients with stable angina pectoris after successful revascularization by PCI with implantation of a bare metal stent (BMS) or a drug eluting stent (DES). Patients were followed for 7 days with serial measurements of inflammatory mediators in plasma. C-reactive protein (CRP) and Pentraxin 3 showed a statistical significant early increase after PCI peaking at 3 days and 3 h, respectively. Vascular cell adhesion molecule-1 (VCAM-1) increased significantly with a peak at 3 days, while E-selectin showed a statistical significant gradual decrease. Markers of platelet mediated inflammation showed increasing (CD40 ligand) and decreasing (P-selectin) levels after PCI. While monocyte chemoattractant protein, CCL21 and CXCL16 increased rapidly in response to PCI, Interleukin-8, CCL19 and RANTES decreased. Patients with DES had significantly lower levels of VCAM-1 and RANTES compared to those with BMS. A femoral access site was associated with higher CRP levels than a radial access site. The use of glycoprotein-IIb/IIIa-inhibitors was associated with significantly higher CD40L and RANTES levels. Our findings underscore the complex nature of the inflammatory responses during PCI in stable CAD, and suggest that simultaneous measurements of several markers may be needed to characterize these PCI-related responses. The responses were only in a minor degree influenced by stent type, access site and the use of glycoprotein-IIb/IIIa-inhibitors.

Variations in population-based levels of C-reactive protein, cardiovascular morbidity and all-cause mortality: an analysis of the relationship between C-reactive protein, Troponin-T, cardiovascular morbidity and death rates in an unselected population in Southwest Norway.

BACKGROUND: Large population-based studies link inflammation to the prospective development of cardiovascular events. We investigated the time-dependent associations between variations in infectious disease as reflected by alterations of C-reactive protein (CRP)-levels in the general population and the number of cardiovascular events and death rates. METHODS: Retrospectively, we studied CRP- and Troponin T (TNT) values drawn for any clinical reason, the number of cardiovascular events and the death rates in the population of Southern Rogaland, Norway over a 2 year period. RESULTS: The mean and the sum of CRP values per week were significantly correlated with the number of patients with a TNT> or =0.03 microg/l in the same week (R=0.42, R=0.43, respectively, p<0.001 for both analysis). Further, we found a significant correlation between the mean and the sum of CRP values per week and the number of patients admitted with a cardiovascular event 2 weeks later (R=0.20, R=0.26; p=0.047, p=0.009, respectively). The sum of CRP values per week was significantly correlated to the death rates in the following week (R=0.30, p=0.002). CONCLUSIONS: These findings further support the hypothesis that inflammation assessed by CRP levels is linked to the prospective development of cardiovascular events and all cause mortality.

High-intensity interval exercise training improves heart rate variability in patients following percutaneous coronary intervention for angina pectoris.

BACKGROUND: Low time domain measures of heart rate variability (HRV) have been shown to predict outcome after myocardial infarction (MI). The predictive value of HRV, when measured in patients with coronary artery disease (CAD) without MI is less clear. Further, little is known about the mechanisms of how autonomic imbalance affects outcome. METHODS AND DESIGN: Forty patients following percutaneous coronary intervention (PCI) with stent implantation for angina pectoris were prospectively randomized to a six month supervised high-intensity interval training program (n=20) or to a control group (n=20). All patients underwent a 24-hour Holter monitoring to assess measures of HRV at baseline and at six months. RESULTS: At baseline there were no significant differences between groups. In the training group all time domain indices and the frequency domain indices, total power and ultralow frequency of HRV, increased significantly during the training period. Mean heart rate decreased significantly. In the control group only the root mean square of differences between successive NN intervals (ln RMSSD) increased significantly. Changes in standard deviations of the average NN intervals (SDANN) and ln RMSSD were significantly correlated to changes in peak VO(2) (R=0.47 and 0.39; p<0.01 and p=0.03 respectively). HRV measures were not significantly correlated to endothelial function. CONCLUSIONS: High-intensity exercise training over 6 months significantly improved time and frequency domain measures of HRV in patients following PCI with stent implantation. The effect on HRV was correlated to changes in peak VO(2), but not to changes in endothelial function.

High-intensity interval training may reduce in-stent restenosis following percutaneous coronary intervention with stent implantation A randomized controlled trial evaluating the relationship to endothelial function and inflammation.

BACKGROUND: High-intensity interval training has been shown to be superior to moderate continuous exercise training in improving exercise capacity and endothelial function in patients with coronary artery disease. The objective of this study was to evaluate this training model on in-stent restenosis following percutaneous coronary intervention for stable or unstable angina. METHODS AND RESULTS: We prospectively randomized 40 patients after percutaneous coronary intervention with implantation of a bare metal stent (n = 30) or drug eluting stent (n = 32) to a 6-month supervised high-intensity interval exercise training program (n = 20) or to a control group (n = 20). At six months, restenosis, measured as in-segment late luminal loss of the stented coronary area, was smaller in the training group 0.10 (0.52) mm compared to the control group 0.39 (0.38) mm (P = .01). Reduction of late luminal loss in the training group was consistent with both stent types. Peak oxygen uptake increased in the training and control group by 16.8% and 7.8%, respectively (P < .01). Flow-mediated dilation improved 5.2% (7.6) in the training group and decreased -0.1% (8.1) in the control group (P = .01). Levels of high-sensitivity C-reactive protein decreased by -0.4 (1.1) mg/L in the training group and increased by 0.1 (1.2) mg/L in the control group (P = .03 for trend). CONCLUSIONS: Regular high-intensity interval exercise training was associated with a significant reduction in late luminal loss in the stented coronary segment. This effect was associated with increased aerobic capacity, improved endothelium function, and attenuated inflammation.