Differential effects of heart rate reduction by atenolol or ivabradine on peripheral endothelial function in type 2 diabetic patients.
Heart
; 98(24): 1812-6, 2012 Dec.
Article
en En
| MEDLINE
| ID: mdl-23086971
ABSTRACT
OBJECTIVE:
To assess whether reduction of heart rate (HR) has beneficial effects on endothelial function in patients with type 2 diabetes mellitus (T2DM).DESIGN:
Randomised, double-blind, placebo-controlled study.SETTING:
University hospital. PATIENTS 66 T2DM patients without overt cardiovascular disease.INTERVENTIONS:
Patients were randomised to receive for 4 weeks, in addition to their standard therapy, one of the following treatments atenolol (25 mg twice daily), ivabradine (5 mg twice daily) or placebo (1 tablet twice daily). MAIN OUTCOMEMEASURES:
Systemic endothelial function, assessed by flow-mediated dilation (FMD); endothelium-independent vasodilation, assessed by nitrate-mediated dilation (NMD); cardiac autonomic function, assessed by HR variability (HRV).RESULTS:
61 patients completed the study (19, 22 and 20 patients in atenolol, ivabradine and placebo groups, respectively). Compared with baseline, HR was similarly reduced by atenolol (87±13 vs 69±9 bpm) and ivabradine (86±12 to 71±9 bpm), but not by placebo (82±10 vs 81±9 bpm) (p<0.001). FMD improved at follow-up in the atenolol group (4.8±1.7 vs 6.4±1.9%), but not in the ivabradine group (5.2±2.5 vs 4.9±2.2%) and in the placebo group (4.8±1.5 vs 4.7±1.7%) (p<0.01). NMD did not change significantly in any group. HRV parameters did not change in the placebo group; they, instead, consistently increased in the atenolol, whereas a mild increase in SDNNi was only observed in the ivabradine group. A significant correlation was found in the atenolol group between HR and FMD changes (r=-0.48; p=0.04).CONCLUSIONS:
Despite a comparable reduction in HR, atenolol, but not ivabradine, improved FMD in T2DM patients suggesting that changes in HR are by themselves unlikely to significantly improve endothelial function.
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Atenolol
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Benzazepinas
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Endotelio Vascular
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Enfermedades Cardiovasculares
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Diabetes Mellitus Tipo 2
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Frecuencia Cardíaca
Tipo de estudio:
Clinical_trials
/
Etiology_studies
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Observational_studies
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Prognostic_studies
Límite:
Female
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Humans
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Male
/
Middle aged
Idioma:
En
Revista:
Heart
Asunto de la revista:
CARDIOLOGIA
Año:
2012
Tipo del documento:
Article
País de afiliación:
Italia