Authors
O’Connor CM, Whellan DJ, Lee KL, et al.
Title
Efficacy and Safety of Exercise Training in Patients With Chronic Heart Failure
References
JAMA. 2009;301(14):1439-1450
Background
Previous small and underpowered studies have suggested that structured exercise in patients with HF may improve survival and decrease hospitalizations. Although these observations remained to be proven, medical guidelines had included recommendations for physical activity to be considered in medically stable patients with systolic dysfunction.
Purpose
To determine if regular structured aerobic exercise, when added to evidence-based pharmacotherapy, reduces death and hospitalizations in stable systolic heart failure patients.
Design
Multicenter, randomized, control trial (event adjudication was blinded) 2331 patients with NYHA class II-IV symptoms, LVEF ≤35% and receiving optimal HF therapy ≥6 weeks (ACE inhibitor or ARB, β-blocker, diuretic, digoxin, aldosterone receptor antagonist if randomized to exercise group, participation in a structured, supervised, group based exercise program for 36 sessions over 3 months and then transitioned to full home based exercise (patients were equipped with cycle or treadmill and heart rate monitors) usual care group received self management educational materials with information for moderate intensity activity for 30 minutes (as tolerated) most days of the week
Exclusion Criteria
major comorbidities or limitations interfering with exercise recent (≤6 weeks) or planned (≤6 months) major cardiovascular events or procedure limited by device with inability to achieve target heart rate regular exercise training
Follow-Up
Median follow-up 30.1 months (minimum 1 year, maximum 4 years)
Treatment Regimen
Aerobic exercise training supervised for 36 sessions then home based exercise, targeting for 60-70% of heart rate reserve for 40 minutes 5 times per week vs. usual care Follow-up visits with the clinic every 3 months for the first two years and yearly thereafter for up to 4 years. Cardiopulmonary exercise testing at 3, 12, 24 months; 6 minute walk test at 3, 12, 24 months, year 3 and final visit.
Results
Primary Endpoints Death from all causes or hospitalization from all causes: 65% (exercise training) vs. 68% (usual care); hazard ratio 0.93 (0.84-1.02), p = 0.13. Adjusting for factors identified as strongly prognostic for an event (LVEF, duration of cardiopulmonary exercise test, Beck Depression II Score and history of atrial fibrillation or flutter), exercise training significantly reduced the primary endpoint by 11%; HR 0.89 (0.81-0.99), p = 0.03 Secondary Endpoints Insignificant reductions in the exercise training group for mortality, CV mortality or CV hospitalization, CV death or heart failure hospitalization Exercise was deemed well tolerated and safe by study authors (refer to Table 2 for details) Adjusting for prognostic factors, exercise training also significantly reduced CV death or HF hospitalizations vs. usual care by 15%; HR 0.85 (0.74-0.99), p = 0.03
Summary
Although safe, aerobic exercise did not significantly reduce rates of all cause death or all cause hospitalization in stable, medically optimized heart failure patients with LVEF 35% and NYHA class II to IV symptoms. However, when adjusted for strong prognostic factors, exercise training did significantly reduce the risk of hospitalization and death, as well as cardiovascular death and heart failure hospitalizations.