Simvastatin improves the attenuated heart rate recovery of type 2 diabetics.

Heart rate recovery at 1min (HRR1) is a strong predictor of all-cause mortality. The effects of statins on the autonomic nervous system may account for their beneficial effects in survival. Our aim was to determine if statin therapy improves heart rate recovery in hypercholesterolemic patients with type 2 diabetes mellitus. Thirty type 2 diabetic patients without known coronary artery disease and low density lipoprotein cholesterol>100mg/dl and 30 age and sex matched non-diabetic controls were included in a prospective study. Patients with diabetes were treated with simvastatin 40mg/day for 1 year. No lipid-lowering therapy was administered to the control group. Exercise testing with 2min cool-down period was performed at baseline, 6, 12 weeks and at 1 year. The diabetics had significantly lower HRR1 compared with non-diabetics at baseline (19.2+/-5.4bpm versus 24.2+/-4bpm, p<0.0001). Simvastatin therapy significantly improved HRR1 after 12 weeks compared to baseline (19.2+/-5.4bpm versus 24+/-5bpm, p<0.0001) and this improvement remained significant at 1 year (26+/-4.4bpm, p<0.0001 compared to baseline). HRR1 did not change in the control group (p=0.39 by ANOVA). This study demonstrates that treatment with simvastatin might improve the attenuated heart rate recovery of diabetic subjects. In patients with diabetes, the mortality benefit provided by statins might involve their effects on the autonomic nervous system.

Decreased heart rate recovery in patients with heart failure: effect of fluvastatin therapy.

Heart rate recovery is the difference in heart rate at peak exercise and at a specific time interval following the onset of recovery. Attenuated heart rate recovery is an independent predictor of mortality in patients with a history of coronary artery disease. The aim of the present study was to evaluate the effect of a statin on heart rate recovery, particularly in patients with ischemic heart failure and hyperlipidemia. Twenty-nine consecutive hyperlipidemic, stable coronary artery disease patients with heart failure and 19 healthy subjects were enrolled. Heart rate recovery values at the 1st and 3rd minutes and lipid profiles of the patients were evaluated at baseline and following 3 months of treatment with fluvastatin. Compared with healthy subjects, the heart rate recovery values were significantly lower in the heart failure patients in both the 1st and 3rd minutes, respectively (31 +/- 6 versus 19 +/- 7, P < 0.0001; 66 +/- 7 versus 47 +/- 8, P < 0.0001). Heart rate recovery in the 1st and 3rd minutes increased from 19 +/- 7 to 24 +/- 9 and 47 +/- 8 to 57 +/- 11, respectively, following treatment (P < 0.001, P < 0.001). There were no significant correlations among the changes in lipid parameters or HRR in the first and third minutes in the recovery period. The results revealed an improvement in heart rate recovery in heart failure patients by fluvastatin treatment. If this association can be confirmed by other studies, it would be interesting to perform further studies into the mechanism underlying this finding.