Effects of cardiac rehabilitation on in vivo nailfold microcirculation in patients with cardiovascular disease.

This study aimed to explore the impact of cardiac rehabilitation (CR) on in vivo and ex vivo microcirculation, exercise capacity, and oxidative stress in patients with cardiovascular disease (CVD). The study included patients with acute coronary syndrome (ACS; n = 45; age, 69.0 ± 14.1 years) and heart failure (HF; n = 66; age, 77.3 ± 10.7 years) who underwent supervised CR during hospitalization. The control group comprised patients without CVD (NCVD; n = 20; age, 75.9 ± 11.2 years). In vivo microcirculatory observations using nailfold video capillary endoscopy at rest and during hyperemia, exercise capacity, and oxidative stress were assessed at baseline and 12 weeks after discharge. Baseline capillary densities were significantly lower in the ACS (5.0 ± 1.7 capillaries/mm 2 ) and HF (4.9 ± 1.7 capillaries/mm 2 ) groups than in the NCVD group (6.5 ± 1.1 capillaries/mm 2 , p < 0.01). Similarly, capillary density during reactive hyperemia was significantly lower in the ACS (5.8 ± 1.7 capillaries/mm 2 ) and HF (5.4 ± 1.8 capillaries/mm 2 ) groups than in the NCVD group (7.3 ± 1.4 capillaries/mm 2 , p < 0.01). Patients with ACS and HF had increased capillary densities at 12 weeks compared with at baseline (p < 0.05). This improvement was particularly pronounced among post-discharge outpatient CR participants (n = 20). Grip strength, exercise capacity, and oxidative stress improved at 12 weeks. Baseline capillary density changes were positively correlated with grip strength changes (r = 0.45, p < 0.001). CR significantly improved nailfold capillary density in patients with ACS and HF 12 weeks after discharge.