Purpose: It has been demonstrated that aerobic exercise induces beneficial changes in coronary atherosclerosis via reduced necrotic core and plaque burden. Clinical factors that may be associated with favorable exercise-induced intracoronary effects are unknown.
Methods: This study used post hoc analysis of associations between baseline clinical variables and reductions in coronary necrotic core and plaque burden after aerobic exercise intervention. Coronary plaque characteristics were measured with grayscale and radiofrequency intravascular ultrasound in 36 patients (median age, 58.5 yr; seven women) with stable CAD (SCAD) or non-ST elevation acute coronary syndrome (NSTE-ACS). Screening of clinical variables was performed with random forest analysis followed by multivariate linear regression.
Results: The only significant clinical variable for necrotic core reduction was clinical presentation of disease (SCAD vs NSTE-ACS, P = 0.011). The changes in necrotic core after exercise were -4.94 mm3 (-10.33; -1.33) in patients with SCAD and 1.03 mm3 (-4.29; 3.71) in patients with NSTE-ACS (P = 0.01). Necrotic core was reduced in 17 patients (94%) with SCAD and eight patients (44%) with NSTE-ACS (P = 0.01). R2 for the model including baseline clinical presentation and baseline necrotic core volume was 0.90. There were no significant explanatory variables for plaque burden reduction.
Conclusions: Exercise-induced plaque stabilization via reduced coronary necrotic core may be strongly dependent on clinical presentation of CAD. We hypothesized that an increased proinflammatory load renders patients with NSTE-ACS more resistant to exercise-induced plaque stabilization than patients with SCAD. Furthermore, aerobic exercise may have a particular potential for inducing beneficial effects on coronary atherosclerosis in patients with SCAD compared with patients in the early phase after an acute coronary syndrome.