Sustained restoration of autonomic balance with long- but not short-acting metoprolol in patients with heart failure.

作者信息

Aquilante Christina L, Terra Steven G, Schofield Richard S, Pauly Daniel F, Hatton Patricia S, Binkley Philip F, Johnson Julie A

机构信息

Department of Pharmacy Practice, University of Florida College of Pharmacy, Gainesville, 32610, USA.

出版信息

J Card Fail. 2006 Apr;12(3):171-6. doi: 10.1016/j.cardfail.2005.12.002.

DOI:10.1016/j.cardfail.2005.12.002

PMID:16624680

Abstract

BACKGROUND

The purpose of this study was to compare the effects of immediate-release (IR) metoprolol and extended-release (XL) metoprolol on measures of heart rate variability in chronic systolic heart failure patients.

METHODS AND RESULTS

Thirteen metoprolol-treated heart failure patients were randomized to a 2-way crossover study of equal daily doses of metoprolol IR and metoprolol XL, each administered for 3 weeks. After each 3-week interval, patients underwent 24-hour Holter and ambulatory blood pressure monitoring. Over the entire 24-hour period, the ratio of high to total variability (normalized measure of parasympathetic activity) was significantly greater (P < .05), the ratio of low to total variability (normalized measure of sympathetic activity) was significantly lower (P < .05), and the ratio of high to low variability (index of parasympathetic to sympathetic balance) was greater (P < .08) for metoprolol XL compared with metoprolol IR. Over the entire 24-hour period, both systolic and diastolic blood pressure were significantly lower for metoprolol XL compared with metoprolol IR (P < .0001, and .0005, respectively).

CONCLUSION

These data suggest that with twice daily dosing, metoprolol IR is inferior to metoprolol XL in its effects on heart rate variability, autonomic balance, and blood pressure in patients with heart failure.

摘要