Arterial Stiffness is Related to Impaired Exercise Capacity in Patients With Coronary Artery Disease and History of Myocardial Infarction.

ABSTRACT

BACKGROUND: Augmented arterial stiffness and reduced cardiorespiratory fitness are associated with increased morbidity and mortality from coronary artery disease (CAD). The relationship between exercise capacity and arterial stiffness is independent of known influencing variables in CAD. This study aimed to analyse the interaction between exercise capacity, arterial stiffness and early vascular ageing in patients with CAD. METHODS: This cross-sectional study included 96 CAD patients with myocardial infarction (55.9±10.9years, 81 men) referred to cardiac rehabilitation. Arterial stiffness was assessed using carotid-femoral pulse wave velocity (cf-PWV). Cardiopulmonary exercise test was performed to measure VO2peak. Comparisons of VO2peak across cf-PWV risk threshold values (high-risk cf-PWV≥10m/s) and tertile groups, and across cf-PWV threshold values and age groups (younger group<60 years) were performed. Correlation tests were used to study the association between pair of variables. RESULTS: Patients with high-risk cf-PWV had lower VO2peak than those with low-risk cf-PWV (p<0.001). VO2peak decreased across tertiles of cf-PWV, showing significantly lower values in the third tertile (p<0.001). There were no differences in the VO2peak between younger patients with high-risk cf-PWV and older patients irrespective of their cf-PWV values. VO2peak showed an upward trend in younger patients with low-risk cf-PWV compared to their age-mates with high-risk cf-PWV (p=0.09). VO2peak was strongly and inversely correlated with cf-PWV (r=-0.502, p<0.001). CONCLUSIONS: Arterial stiffening is associated with lower cardiorespiratory fitness in CAD patients with myocardial infarction. When its values are above risk threshold, exercise capacity is impaired regardless of the relationship between age and arterial stiffness.