Cardiovascular effects of a phosphodiesterase III inhibitor, amrinone, in infants: non-invasive echocardiographic evaluation.
OBJECTIVE
The inotropic effect of amrinone is still controversial in management of congestive heart failure in pediatric patients, especially in infants. In order to determine the cardiovascular effect of amrinone in pediatric patients, we performed echocardiographic evaluation in 11 infants (mean age of 2 months) after intracardiac surgery.


METHODS
Amrinone was loaded with a dose of 1.0 mg/kg, followed by continuous infusion with 10 microg/kg per min. We performed echocardiographic measurements before and immediately after loading of amrinone, and evaluated its cardiovascular effect.


RESULTS
After loading of amrinone, the heart rate increased by 5% in average, but there was no change in blood pressure. Left ventricular (LV) fractional shortening and mean velocity of circumferential fiber shortening corrected for heart rate increased significantly (0.25 +/- 0.09 to 0.28 +/- 0.08 and 0.94 +/- 0.35 to 1.10 +/- 0.34, respectively). Left ventricular end-systolic wall stress decreased from 36.6 +/- 18.5 to 29.1 +/- 14.4 g/cm2, indicating the reduction of LV afterload. Stress-velocity index, a sensitive index of left ventricular contractility, was elevated significantly (Z-score: -1.45 +/- 4.21 to 0.04 +/- 4.11).


CONCLUSIONS
Amrinone has not only vasodilative effects, but definite positive inotropic effects in infants with heart failure.
Teshima
Hidetaka
H
Department of Pediatric Cardiology,The Heart Institute of Japan, Tokyo Women's Medical University, Tokyo, Japan. teshima@nmc.hosp.go.jp
Tobita
Kimimasa
K
Yamamura
Hideshi
H
Takeda
Atsuhito
A
Motomura
Hideki
H
Nakazawa
Makoto
M
D015105:3',5'-Cyclic-AMP Phosphodiesterases / Q000037:antagonists & inhibitors; D000676:Amrinone / Q000494:pharmacology*; D006348:Cardiac Surgical Procedures; D002316:Cardiotonic Agents / Q000494:pharmacology*; D054684:Cyclic Nucleotide Phosphodiesterases, Type 3; D004452:Echocardiography; D005260:Female; D006321:Heart / Q000187:drug effects*; D006330:Heart Defects, Congenital / Q000503:physiopathology / Q000601:surgery*; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology*; D014665:Vasodilator Agents / Q000494:pharmacology*
D002316:Cardiotonic Agents; D010726:Phosphodiesterase Inhibitors; D014665:Vasodilator Agents; D015105:3',5'-Cyclic-AMP Phosphodiesterases; D054684:Cyclic Nucleotide Phosphodiesterases, Type 3; D000676:Amrinone