PT  - JOURNAL ARTICLE
AU  - Olav R. de Peuter
AU  - Hein J. Verberne
AU  - Wouter E. Kok
AU  - Bas van den Bogaard
AU  - Marianna C. Schaap
AU  - Rienk Nieuwland
AU  - Joost C.M. Meijers
AU  - G. Aernout Somsen
AU  - Ad Bakx
AU  - Pieter W. Kamphuisen
TI  - Differential Effects of Nonselective Versus Selective β-Blockers on Cardiac Sympathetic Activity and Hemostasis in Patients with Heart Failure
AID  - 10.2967/jnumed.113.120477
DP  - 2013 Oct 01
TA  - Journal of Nuclear Medicine
PG  - 1733--1739
VI  - 54
IP  - 10
4099  - http://jnm.snmjournals.org/content/54/10/1733.short
4100  - http://jnm.snmjournals.org/content/54/10/1733.full
SO  - J Nucl Med2013 Oct 01; 54
AB  - Carvedilol, a nonselective β-blocker, may be more effective than the selective β-blocker metoprolol in reducing the risk of thromboembolic events in heart failure. The aim of this study was, first, to assess whether there is a differential response in cardiac sympathetic activity by 123I-meta-iodobenzylguanidine (123I-MIBG) imaging when either β-blocker is used. Second, we assessed whether that response correlates with levels of various serum factors that serve as markers for coagulability. Methods: In this prospective, randomized, open-label crossover study with masked outcome assessments, stable heart failure patients (left ventricular ejection fraction < 40%) homozygous for the Arg16/Gln27 (n = 13) or Gly16/Glu27 haplotype (n = 8) of the β2-receptor were randomized to equipotent dosages of carvedilol or metoprolol for two 6-wk periods. Primary outcome was sympathetic activity as measured by 123I-MIBG myocardial washout. Secondary outcomes included markers of hemostasis. Results: 123I-MIBG cardiac washout was lower during carvedilol than metoprolol treatment (12.9% ± 3.9% vs. 22.1% ± 2.8%, respectively, P = 0.003), irrespective of β2-adrenergic receptor haplotype. In addition, treatment with carvedilol resulted in a lower von Willebrand factor than did metoprolol (149% ± 13% vs. 157% ± 13%, respectively, P = 0.01), irrespective of β2-adrenergic receptor haplotype. Conclusion: Compared with metoprolol, carvedilol resulted in greater reduction of sympathetic activity after 6 wk of treatment and lower von Willebrand factor concentrations in both Arg16/Gln27 and Gly16/Glu27 individuals. Therefore, carvedilol may reduce the risk of thromboembolic events in patients with heart failure, irrespective of β2-receptor haplotype status.