TY - JOUR
T1 - Differences in hemodynamic effects of nitroprusside and prazosin in severe chronic congestive heart failure. Evidence for a direct negative chronotropic effect of prazosin
AU - Packer, Milton
AU - Meller, Jose
AU - Gorlin, Richard
AU - Herman, Michael V.
N1 - Funding Information:
From the Division of Cardiology, Department of Medicine, The Mount Sinai School of Medicine of the city University of New York. 1 Gustave Levy Place. New York. New York. This study was sup ported in part by grants from theHeart Research Foundation, Inc. and the Kriendler-Berns Foun- datii, New York, New York. ManuWript received December 17, 1978; revised manuscript received March 20, 1979. accepted April 2, 1979.
PY - 1979/8
Y1 - 1979/8
N2 - To compare the hemodynamic effects of prazosin and nitroprusside in patients with severe congestive heart failure, nine patients with heart failure refractory to conventional therapy received oral prazosin and intravenous nitroprusside administered so as to produce a similar decrease in left ventricular filling pressure in each patient. By this comparison, both drugs produced similar decreases in mean right atrial pressure, mean pulmonary arterial pressure and systemic and pulmonary vascular resistance. However, with nitroprusside, cardiac index increased more (+ 0.97 versus +0.73 liters/min per m2, P < 0.01) and mean arterial pressure decreased less (-13.7 versus - 18,3 mm Hg, P < 0.05) than with prazosin. Both drugs produced similar changes in stroke volume index (+11.7 cc/beat per m2 with nitroprusside and +12.5 with prazosin) and stroke work index (+8.1 g-m/m2 with nitroprusside and +6.6 with prazosin). Therefore, the differences In the hemodynamic responses observed with the two agents were due to the significantly greater decrease in heart rate with prazosin (-8 beats/min) than with nitroprusside (-2 beats/min, P < 0.05). These clinical data support experimental evidence suggesting that there is a significant negative Chronotropic action of prazosin independent of its peripheral vascular effects.
AB - To compare the hemodynamic effects of prazosin and nitroprusside in patients with severe congestive heart failure, nine patients with heart failure refractory to conventional therapy received oral prazosin and intravenous nitroprusside administered so as to produce a similar decrease in left ventricular filling pressure in each patient. By this comparison, both drugs produced similar decreases in mean right atrial pressure, mean pulmonary arterial pressure and systemic and pulmonary vascular resistance. However, with nitroprusside, cardiac index increased more (+ 0.97 versus +0.73 liters/min per m2, P < 0.01) and mean arterial pressure decreased less (-13.7 versus - 18,3 mm Hg, P < 0.05) than with prazosin. Both drugs produced similar changes in stroke volume index (+11.7 cc/beat per m2 with nitroprusside and +12.5 with prazosin) and stroke work index (+8.1 g-m/m2 with nitroprusside and +6.6 with prazosin). Therefore, the differences In the hemodynamic responses observed with the two agents were due to the significantly greater decrease in heart rate with prazosin (-8 beats/min) than with nitroprusside (-2 beats/min, P < 0.05). These clinical data support experimental evidence suggesting that there is a significant negative Chronotropic action of prazosin independent of its peripheral vascular effects.
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U2 - 10.1016/0002-9149(79)90322-9
DO - 10.1016/0002-9149(79)90322-9
M3 - Article
C2 - 463769
AN - SCOPUS:0018608293
SN - 0002-9149
VL - 44
SP - 310
EP - 317
JO - The American journal of cardiology
JF - The American journal of cardiology
IS - 2
ER -