Cardiac rehabilitation in patients with peripheral arterial disease after revascularization.

OBJECTIVES: To evaluate safety, feasibility, and benefit of cardiac rehabilitation (CR) in patients with peripheral arterial disease (PAD) who undergo revascularization. METHODS: We conducted a prospective, non-randomized, pilot study to assess the feasibility, safety, and benefit of CR in PAD patients after revascularization compared to standard of care (controls). CR feasibility was assessed by the ability to complete 36 sessions. Safety was defined as the absence of adverse cardiovascular events during CR. Quality of life (QoL) assessment was performed using SF-36 form (Medical Outcomes Study 36-Item Short-Form Health Survey) and PAD-specific quality of life questionnaire (VascuQOL6). Other endpoints included incidence of claudication during 6-minute walk test (6MWT), mean distance, and number of laps walked. All outcome data were collected before and after CR completion. Standard statistical tests were used for comparisons. RESULTS: This study enrolled 20 subjects (CR group = 10). Mean age was 60.70 (±7.13) and 63.1 (±9.17) years in CR and controls, respectively (p-value > 0.05). Fifty percent and 60% were female in CR and control group, respectively. All subjects completed 36 CR sessions without adverse events. The increase in mean distance walked during 6MWT was higher in the CR group compared to control group (63.7 m vs. 10.5 m, p = 0.043). Change in mean number of laps walked was higher in the CR group (3.5 vs. -1.1; p < 0.01). Scores on 6 of 8 scales of SF-36 and VascuQOL6 were higher in the CR group, though not statistically significant. CONCLUSION: CR is safe, feasible, and improves walking ability in ambulatory patients with PAD after arterial revascularization.

Validity of a Submaximal 6-min Recumbent Stepper Test for Cardiac Rehabilitation.

PURPOSE: Submaximal exercise tests, such as the 6-min walk test (6MWT), are used to assess and determine changes in cardiorespiratory fitness in cardiopulmonary rehabilitation (CR) programs. However, other modalities such as recumbent steppers are frequently utilized in rehabilitation settings and suit individuals of all ability levels; yet, no self-paced submaximal test has been developed for this exercise modality. The aim of this study was to produce a self-paced, submaximal 6-min recumbent stepper test (6MRST) that is comparable with the 6MWT and can be used as pre- and post-CR assessments. METHODS: Seventy subjects participating in CR performed a 6WMT and a 6MRST at the beginning and end of their CR program. Distance exercised, blood pressure, heart rate, and perceived exertion were measured to determine whether the 6MRST was comparable with the 6MWT. RESULTS: Significant correlations were found between the distance exercised in the 6MWT and the 6MRST during both pre- and post-CR testing (r = 0.540 and r = 0.700, respectively; P < .001). The distance for the 6MRST increased from 1599 to 2101 ft after CR. Heart rate and rating of perceived exertion showed strong correlations between the 6MWT and the 6MRST at both testing time points. CONCLUSIONS: The 6MRST was found to produce similar results to that of the 6MWT in a CR setting. The 6MRST could therefore serve as an alternative to the 6MWT in those patients who cannot adequately perform a 6MWT, in a facility where space may be too limited, and a walking track is not available or simply due to patient or staff preference.

Differences in outcomes between patients treated with single- versus dual-chamber implantable cardioverter defibrillators: a substudy of the Multicenter Automatic Defibrillator Implantation Trial II.

OBJECTIVES: We sought to evaluate the influence of single- versus dual-chamber implantable cardioverter defibrillators (ICDs) on the occurrence of heart failure and mortality as well as appropriate and inappropriate ICD therapy in the Multicenter Automatic Defibrillator Implantation Trial II (MADIT-II). BACKGROUND: In MADIT-II, ICD therapy in patients with a prior myocardial infarction and ejection fraction < or =0.30 was associated with a 31% reduction in risk of mortality when compared to conventionally treated patients. An unexpected finding was an increased occurrence of hospitalization for heart failure in the ICD group. METHODS: Data from 717 patients randomized to ICD therapy with single- or dual-chamber pacing devices in MADIT-II were retrospectively analyzed. Endpoints selected for analysis included death from any cause, new or worsening heart failure requiring hospitalization, death or heart failure, appropriate therapy for ventricular tachycardia (VT) or ventricular fibrillation (VF), and inappropriate ICD therapy for atrial fibrillation or supraventricular tachycardia. RESULTS: A total of 404 single-chamber ICDs (S-ICDs) and 313 dual-chamber ICDs (D-ICDs) were implanted. Patients receiving D-ICDs were at a higher risk at baseline than those receiving S-ICDs, with older age, higher NYHA class, more frequent prior CABG, wider QRS complex, more LBBB, higher BUN level, a history of more atrial arrhythmias requiring treatment, and a longer time interval from their index myocardial infarction to enrollment. While there was a trend toward an increase in adverse outcomes in the D-ICD group, no statistically significant differences in heart failure or mortality were observed between S-ICD versus D-ICD groups. CONCLUSIONS: Patients with D-ICDs had a nonsignificant trend toward higher mortality and heart failure rates than patients with S-ICDs.