A Ferro1, M Salvatore, A Cuocolo. 1. Department of Biomorphological and Functional Sciences, Nuclear Medicine Center of the National Council of Research (CNR), University Federico II, Napoli, Italy.
Abstract
BACKGROUND: This study investigates the acute effects of nifedipine administration on left ventricular (LV) function in patients with different degrees of heart failure at a fixed heart rate under resting conditions and during moderate physical activity. METHODS AND RESULTS: Eleven patients with non-rate-responsive DDD pacemakers were studied. According to baseline LV ejection fraction, patients were divided into 2 groups: 6 patients with an ejection fraction of less than 50% (group 1) and 5 patients with an ejection fraction of 50% or more (group 2). LV function was monitored by a radionuclide system (Vest) at rest and during moderate physical activity (10-minute walk test) before and after sublingual nifedipine administration (10 mg). In all patients, both the systolic blood pressure and diastolic blood pressure were significantly reduced (P <.05) 6 minutes after nifedipine administration. In group 1, end-diastolic volume and ejection fraction decreased after 3 minutes and remained significantly lower (P <.05) than resting values until 10 minutes after drug administration, whereas end-systolic volume was unchanged. In group 2, nifedipine induced a minor decrease in end-diastolic volume and a slight but not significant decrease in ejection fraction and end-systolic volume. During the walk test, nifedipine induced similar changes in all parameters of cardiac performance in both groups. CONCLUSIONS: In patients with impaired LV function, acute nifedipine administration has a negative effect on cardiac performance, which occurs before blood pressure reduction. On the other hand, during moderate physical activity, nifedipine does not affect the improvement in LV function.
BACKGROUND: This study investigates the acute effects of nifedipine administration on left ventricular (LV) function in patients with different degrees of heart failure at a fixed heart rate under resting conditions and during moderate physical activity. METHODS AND RESULTS: Eleven patients with non-rate-responsive DDD pacemakers were studied. According to baseline LV ejection fraction, patients were divided into 2 groups: 6 patients with an ejection fraction of less than 50% (group 1) and 5 patients with an ejection fraction of 50% or more (group 2). LV function was monitored by a radionuclide system (Vest) at rest and during moderate physical activity (10-minute walk test) before and after sublingual nifedipine administration (10 mg). In all patients, both the systolic blood pressure and diastolic blood pressure were significantly reduced (P <.05) 6 minutes after nifedipine administration. In group 1, end-diastolic volume and ejection fraction decreased after 3 minutes and remained significantly lower (P <.05) than resting values until 10 minutes after drug administration, whereas end-systolic volume was unchanged. In group 2, nifedipine induced a minor decrease in end-diastolic volume and a slight but not significant decrease in ejection fraction and end-systolic volume. During the walk test, nifedipine induced similar changes in all parameters of cardiac performance in both groups. CONCLUSIONS: In patients with impaired LV function, acute nifedipine administration has a negative effect on cardiac performance, which occurs before blood pressure reduction. On the other hand, during moderate physical activity, nifedipine does not affect the improvement in LV function.
Authors: M D Feldman; J D Alderman; J M Aroesty; H D Royal; J J Ferguson; R M Owen; W Grossman; R G McKay Journal: J Clin Invest Date: 1988-11 Impact factor: 14.808
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Authors: S Matsumoto; T Ito; T Sada; M Takahashi; K M Su; A Ueda; F Okabe; M Sato; I Sekine; Y Ito Journal: Am J Cardiol Date: 1980-09 Impact factor: 2.778