Tocolytic Agents and Heart Disease

Babies delivered prior to term gestation are typically at higher risk for mortality and poor health. Doctors sometime recommend using preterm labor therapy to lengthen gestation. However, preterm labor therapy with tocolytic agents can have adverse effects on heart function.

Description

• Tocolytic agents inhibit preterm labor They are mainly used to delay delivery for 48 hours to maximize the effect of glucocorticoids and reduce the incidence of respiratory distress in premature babies, says Medscape.

Types

• Drugs used as tocolytic agents usually have other uses and different mechanisms of action. Examples of these include terbutaline, salbutamol, ritodrine, magnesium sulfate and Indomethacin Nifedipine:

Maternal Effects

• Possible cardiovascular side effects of tocolytics on the mother include edema, low blood pressure (hypotension), palpitations, heart rate disturbances (arrhythmias), flushing, shortness of breath, chest pain, respiratory depression, bleeding disorders, congestive heart failure and elevated blood pressure in hypertensive patients.

Fetal/Neonatal Effects

• According to Medscape, possible cardiovascular side effects on the fetus or newborn include elevated heartbeat (tachycardia), increased risk of hemorrhage between the ventricles (heart chambers), lethargy, respiratory depression, pulmonary hypertension, postpartum patent ductus arteriosus (a heart defect) and low blood pressure.

Warning

• The use of tocolytics is particularly risky for pregnant patients with cardiac disease, especially those with a history of congestive heart failure, cardiac surgery, pulmonary disease and renal failure, says Healthline.

Considerations

• Clinical studies are not conclusive about the effectiveness of tocolytics at preventing premature birth or reducing neonatal mortality. Though slightly less effective, bed rest and hydration have fewer adverse effects.