ESC Professional Members, Association Members (Ivory & above) benefit from year-round access to all the resources from their respective Association, and to all content from previous years. Fellows of the ESC (FESC), and professionals in training or under 40 years old, who subscribed to a Young Combined Membership package benefit from access to all ESC 365 content from all events, all editions, all year long. Find out more about ESC Memberships here.
Peak oxygen uptake during exercise testing and long-term cardiovascular events in patients with coronary artery disease undergoing cardiac rehabilitation: a population-based study
Authors : J R Medina-Inojosa (Rochester,US), TA Allison (Rochester,US), V Somers (Rochester,US), RJ Thomas (Rochester,US), MA Gomez Ibarra (Rochester,US), S Leth (Rochester,US), L Barr (Rochester,US), N Jean (Rochester,US), F Lopez-Jimenez (Rochester,US)
J.R. Medina-Inojosa1
,
T.A. Allison1
,
V. Somers1
,
R.J. Thomas1
,
M.A. Gomez Ibarra1
,
S. Leth1
,
L. Barr1
,
N. Jean1
,
F. Lopez-Jimenez1
,
1Mayo Clinic - Rochester - United States of America
,
Topic(s): Cardiovascular rehabilitation: interventions and outcomes
Background: Measurement of percentage of predicted peak oxygen consumption (%VO2) during cardiopulmonary exercise testing has been shown to predict mortality in patients with coronary artery disease (CAD).Its association with major adverse cardiovascular events (MACE) has not been determined.
Purpose: To test the hypothesis that decreased exercise capacity (represented by %VO2) is associated with long-term MACE in patients with CAD in the community.
Methods: We performed a community-based retrospective longitudinal study on stable CAD patients entering Phase II cardiac rehabilitation between the years 2002 through 2012 and who completed a symptom-limited graded VO2 treadmill exercise test. VO2 was computed using a Medical Graphics CPX/D metabolic cart after collecting expired gases. %VO2 was estimated using the Astrand equation for men and the Jones equation for women. The composite outcome of MACE included acute coronary syndromes (myocardial infarction or unstable angina), coronary artery bypass graft, percutaneous coronary revascularization, ventricular arrhythmias requiring hospitalization, stroke or death from any cause, and was ascertained using a record linkage system.Cox proportional hazard models were adjusted for age, gender, and factors known to affect both exercise capacity and MACE (See table).
Results: Our cohort included 887 patients, 77% males, mean age 63±12 years. After a mean follow-up of 5 years, 172 patients had a MACE (#): MI (50), unstable angina (33), CABG (14), PCI (93), ventricular arrhythmia (5), stroke (17) and death (25). Normal or increased exercise capacity was related to lower rate of MACE (HR 0.43, 95% CI 0.21–0.79, p=0.04) comparing those with %VO2 ≥100% to those with %VO2 <100%.The lower the %VO2 the higher the rate of MACE (See table). Per each 1 mL/kg/min decrease in % VO2 the risk for MACE increased 1% (HR 1.01, p=0.02).
Conclusion: Patients with normal or increased exercise capacity had reduced rates of MACE events. The lower the %VO2 the higher the rate of MACE, suggesting that exercise capacity at time of cardiac rehabilitation predicts cardiovascular outcomes.
Model 1
Model 2
HR
95% CI
P value
HR
95% CI
P value
1-%VO2: ≥100%
reference
reference
2-%VO2: 80–100%
2.14
(1.13–4.49)
0.018
2.04
(1.07–4.30)
0.027
3-%VO2: 60–80%
2.48
(1.32–5.18)
0.003
2.54
(1.33–5.36)
0.003
4-%VO2: ≤60%%
2.52
(1.26–5.50)
0.253
2.74
(1.33–6.09)
0.005
Model 1 = adjusted for age and gender, Model 2 = adjusted for age, gender, body mass index, history of heart failure, peripheral vascular disease, myocardial infarction and smoking. %VO2 = Percent-predicted peak oxygen uptake, expressed in (mL/kg/min), HR = Hazard ratio, CI = confidence interval. P value for %VO2 categories in univariate analysis = 0.04, P for model 1 = 0.03, P for model 2 = 0.02. No significant interaction between history of myocardial infarction, smoking and %VO2 was observed.
ESC Professional Members, Association Members (Ivory & above) benefit from year-round access to all the resources from their respective Association, and to all content from previous years. Fellows of the ESC (FESC), and professionals in training or under 40 years old, who subscribed to a Young Combined Membership package benefit from access to all ESC 365 content from all events, all editions, all year long. Find out more about ESC Memberships here.
