TY - JOUR
T1 - Effect of chronic tocolytic therapy on maternal ventricular function in pregnant rabbits
AU - Russo, L. R.
AU - Besinger, R. E.
AU - Tomich, P. G.
AU - Thomas, Jr
PY - 1996
Y1 - 1996
N2 - OBJECTIVE: Our purpose was to determine whether peripartum cardiomyopathy may be associated with chronic β-mimetic tocolytic therapy. STUDY DESIGN: On gestational day 20 (term 31 days), two 200 μl Alzet miniosmotic pumps were implanted in the subcutaneous tissue of pregnant New Zealand White rabbits. Each pump was filled with terbutaline (20 μg/μl, n = 7) or saline solution (0.9%, n = 7) and infused continuously for 7 days. The rabbits were killed on the twenty-eighth gestational day. Maternal hearts were placed on a Langendorff (nonejecting) perfusion apparatus for assessment of cardiac function. At a constant perfusion pressure and heart rate left ventricular diastolic pressure was varied while left ventricular developed pressure and left ventricular ± rate of pressure rise, index values of left ventricular contractility and relaxation, were continuously recorded. Comparisons between groups at each preload were made by analysis of variance. RESULTS: Hearts taken from terbutaline-treated rabbits exhibited periodic arrhythmias and mechanical alternans in five of seven hearts versus one of seven in the saline solution group. At a preload of 0 mm Hg both left ventricular developed pressure (88.0 vs 48.4 mm Hg, p < 0.001) and left ventricular rate of pressure rise (1406 vs 653 mm Hg/sec, p < 0.001) were less in terbutaline-treated rabbits. At a preload of 10 mm Hg left ventricular developed pressure (104.4 vs 86.7 mm Hg, p < 0.01) and rate of pressure rise (1424 vs 694 mm Hg/sec, p < 0.001) were also significantly less in terbutaline-treated rabbits. Left ventricular relaxation was also impaired at all preloads. CONCLUSIONS: In this model chronic administration of terbutaline during late pregnancy significantly depresses global maternal cardiac function.
AB - OBJECTIVE: Our purpose was to determine whether peripartum cardiomyopathy may be associated with chronic β-mimetic tocolytic therapy. STUDY DESIGN: On gestational day 20 (term 31 days), two 200 μl Alzet miniosmotic pumps were implanted in the subcutaneous tissue of pregnant New Zealand White rabbits. Each pump was filled with terbutaline (20 μg/μl, n = 7) or saline solution (0.9%, n = 7) and infused continuously for 7 days. The rabbits were killed on the twenty-eighth gestational day. Maternal hearts were placed on a Langendorff (nonejecting) perfusion apparatus for assessment of cardiac function. At a constant perfusion pressure and heart rate left ventricular diastolic pressure was varied while left ventricular developed pressure and left ventricular ± rate of pressure rise, index values of left ventricular contractility and relaxation, were continuously recorded. Comparisons between groups at each preload were made by analysis of variance. RESULTS: Hearts taken from terbutaline-treated rabbits exhibited periodic arrhythmias and mechanical alternans in five of seven hearts versus one of seven in the saline solution group. At a preload of 0 mm Hg both left ventricular developed pressure (88.0 vs 48.4 mm Hg, p < 0.001) and left ventricular rate of pressure rise (1406 vs 653 mm Hg/sec, p < 0.001) were less in terbutaline-treated rabbits. At a preload of 10 mm Hg left ventricular developed pressure (104.4 vs 86.7 mm Hg, p < 0.01) and rate of pressure rise (1424 vs 694 mm Hg/sec, p < 0.001) were also significantly less in terbutaline-treated rabbits. Left ventricular relaxation was also impaired at all preloads. CONCLUSIONS: In this model chronic administration of terbutaline during late pregnancy significantly depresses global maternal cardiac function.
KW - Chronic terbutaline tocolysis
KW - rabbits
KW - ventricular function
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U2 - 10.1016/S0002-9378(96)80011-1
DO - 10.1016/S0002-9378(96)80011-1
M3 - Article
C2 - 8885734
AN - SCOPUS:0029909413
SN - 0002-9378
VL - 175
SP - 847
EP - 852
JO - American Journal of Obstetrics and Gynecology
JF - American Journal of Obstetrics and Gynecology
IS - 4 I
ER -