| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
From the Division of Cardiothoracic Surgery, Medical University of South
Carolina, Charleston, and Pfizer Central Research, Sandwich, UK (M.G.D.).
Correspondence to Francis G. Spinale, MD, PhD, Cardiothoracic Surgery, Room 418 CSB, Medical University of South Carolina, 171 Ashley Ave, Charleston, SC 29425.
BackgroundThis study examined
the effects of chronic amlodipine treatment on left
ventricular (LV) pump function, systemic
hemodynamics, neurohormonal status, and regional blood
flow distribution in an animal model of congestive heart failure (CHF)
both at rest and with treadmill exercise. In an additional series of in
vitro studies, LV myocyte contractile function was examined.
Methods and ResultsSixteen pigs were studied under normal
control conditions and after the development of chronic pacinginduced
CHF (240 bpm, 3 weeks, n=8) or chronic pacing and amlodipine (1.5
mg · kg-1 · d-1, n=8). Under
ambient resting conditions, LV stroke volume (mL) was reduced with CHF
compared with the normal control state (16±2 versus 31±2,
P<0.05) and increased with concomitant amlodipine
treatment (29±2, P<0.05). At rest, systemic and
pulmonary vascular resistance (dyne ·
s-1 · cm-5) increased with CHF
compared with the normal control state (3102±251 versus 2156±66 and
1066±140 versus 253±24, respectively, both P<0.05)
and were reduced with amlodipine treatment (2108±199 and 480±74,
respectively, P<0.05). With CHF, LV stroke volume
remained reduced and was associated with a 40% reduction in myocardial
blood flow during treadmill exercise, whereas chronic amlodipine
treatment normalized LV stroke volume and improved myocardial blood
flow. Resting and exercise-induced plasma norepinephrine
levels were increased by >5-fold in the CHF group and were reduced by
50% from CHF values with chronic amlodipine treatment. Resting plasma
endothelin (fmol/mL) increased with CHF compared with the normal state
(10.4±0.9 versus 3.1±0.3, P<0.05) and was reduced
with amlodipine treatment (6.6±1.1, P<0.5). With CHF,
LV myocyte velocity of shortening (µm/s) was reduced compared with
normal controls (39±1 versus 64±1, P<0.05) and was
increased with chronic amlodipine treatment (52±1,
P<0.05).
ConclusionsChronic amlodipine treatment in this model of
developing CHF produced favorable hemodynamic,
neurohormonal, and contractile effects in the setting of developing
CHF.
© 1998 American Heart Association, Inc.
Basic Science Reports
Chronic Amlodipine Treatment During the Development of Heart Failure
Key Words: calcium channel blockers heart failure blood flow hormones
This article has been cited by other articles:
![]() |
S. Baudet Hypertrophy and dilation: a TOTally new story? Cardiovasc Res, April 1, 2000; 46(1): 17 - 19. [Full Text] [PDF] |
||||
|
Circulation Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 1998 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |