Verapamil acutely reduces ventricular-vascular stiffening and improves aerobic exercise performance in elderly individuals.
J Am Coll Cardiol
; 33(6): 1602-9, 1999 May.
Article
de En
| MEDLINE
| ID: mdl-10334431
ABSTRACT
OBJECTIVES:
We tested the hypothesis that acute intravenous verapamil acutely enhances aerobic exercise performance in healthy older individuals in association with a combined reduction of ventricular systolic and arterial vascular stiffnesses.BACKGROUND:
Age-related vascular stiffening coupled with systolic ventricular stiffening may limit cardiovascular reserve and, thus, exercise performance in aged individuals.METHODS:
Nineteen healthy volunteers with mean age 70 +/- 10 years underwent maximal-effort upright ergometry tests on two separate days after receiving either 0.15 mg/kg i.v. verapamil or 0.5 N saline in a double-blind, randomized, crossover study.RESULTS:
Baseline vascular stiffness, indexed by arterial pulse-wave velocity (Doppler) and augmentation index (carotid tonometry) declined with verapamil (-5.9 +/- 2.1% and -31.7 +/- 12.8%, respectively, both p < 0.05). Preload-adjusted maximal ventricular power, a surrogate for ventricular end-systolic stiffness, also declined by -9.5 +/- 3.6%. Peripheral resistance and peak filling rate were unchanged. With verapamil, exercise duration prior to the anaerobic threshold (AT) increased by nearly 50% (260 +/- 129 to 387 +/- 176 s) with a corresponding 13.4 +/- 4.7% rise in oxygen consumption (VO2) at that time (both p < 0.01). Total exercise duration prolonged by +6 +/- 2.7% (p < 0.05) with no change in maximal VO2. Baseline cardiodepression from verapamil reversed by peak exercise with net increases in stroke volume and cardiac output (p < 0.05).CONCLUSIONS:
Acute intravenous verapamil reduces ventriculovascular stiffening and improves aerobic exercise performance in healthy aged individuals. This highlights a role for heart-arterial coupling in modulating exertional capacity in the elderly, suggesting a potentially therapeutic target for aged individuals with exertional limitations.
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Collection:
01-internacional
Base de données:
MEDLINE
Sujet principal:
Résistance vasculaire
/
Inhibiteurs des canaux calciques
/
Vérapamil
/
Épreuve d'effort
/
Contraction myocardique
Type d'étude:
Clinical_trials
Limites:
Aged
/
Aged80
/
Female
/
Humans
/
Male
/
Middle aged
Langue:
En
Journal:
J Am Coll Cardiol
Année:
1999
Type de document:
Article
Pays d'affiliation:
États-Unis d'Amérique