Objectives β-block can reduce the rate of progression of atherosclerosis caused by increased sympathetic activity. However, the percentage reduction in resting heart rate (RHR) in relation to the progression of coronary atherosclerosis in patients with established coronary artery disease (CAD) remains uncertain.
Methods We performed retrospective chart review of 318 patients with established CAD who underwent 2 coronary angiographies (CAG). Progression of coronary atherosclerosis was defined as in-stent restenosis, or increasing stenosis of 20% or more in luminal diameter than baseline.
Results After a median follow-up of 24 months between coronary angiographies, 147(46.2%) patients developed progressive coronary atherosclerosis. There were no significant differences in baseline RHR (74.71 ± 10.67 vs 76.21 ± 10.74, p = 0.211) among patients with and without progression of coronary atherosclerosis. The use of beta-blockers, statins, aspirin, clopidogrel, angiotensin-converting enzyme inhibitors, and angiotensin receptor blockers were also similar between two groups from baseline to follow-up. However, RHR was significantly higher in patients with progressive disease than those in the non-progressive group (74.75 ± 11.04 vs 71.99 ± 9.39, p = 0.017) in the second CAG, and there was significant difference in the changes between two RHR between two groups (-0.041 ± 12.30 vs 4.14 ± 11.73, p<0.001). After multivariate adjustment accounting for age, gender, smoking, number of diseased vessels, stent implantation, serum LDL-C level, LDL-C reduction and RHR reduction, et al, achieving RHR reduction of 20% or more showed significantly reduced progression of coronary atherosclerosis (Odds ratio [OR] 0.352, 95% confidence interval [CI], 0.139-0.894, p = 0.028).
Conclusions The current study suggests that the benefit of β-block therapy in progression of coronary atherosclerosis is in proportion to the reduction in RHR. More than 20% reduce in RHR may bring more benefit for the prevention of coronary atherosclerosis progress.