[Heart function in infants and small children, whose mothers required tocolysis with hexoprenaline sulfate...

Cardiac function was investigated in 23 retrospectively selected children (mean age 15 months, range 2/12-3 4/12), whose mothers had undergone a successful course of tocolysis around the 31st week of pregnancy. Hexoprenaline sulfate (Gynipral) had been given at a mean cumulative dose of 51,103 micrograms over an average period of 13.8 days. The infants were born at term; cases with marked birth asphyxia, low birth weight or other perinatal problems possibly influencing cardiac performance were not included. The examination included a chest X-ray, ECG (all standard leads) and ultrasonography. There was no evidence of myocardial dysfunction which might have been the late result of untoward effects of the beta 2-mimetics given during the last trimester of pregnancy. All probands were normally developed: on cardiological examination an incidental systolic murmur was found in 2 infants and border-line cardiomegaly in another proband. ECG revealed a wandering pace-maker and occasional ventricular extrasystoles in one 3 month-old boy, which is not necessarily abnormal at this age. Two-dimensional echocardiography showed normal cardiac anatomy in all 23 probands. One-dimensional M-mode showed normal left ventricular function parameters. The slightly elevated myocardial contractility demonstrated by means of the M-mode was attributed to increased sympathetic tone in the non-sedated children.