MUNICH — For women who were born with a congenital heart defect that was subsequently repaired, a healthy, event-free pregnancy is a roll of the dice.
“The risk to the mother and child is considerable in some cases, but not in all women” who become pregnant after having an atrial switch operation for transposition of the great arteries (TGA) as a child, Dr. Vessie Trigas said at the annual meeting of the European Society of Cardiology.
The risk is “unpredictable,” and therefore, these women need careful follow-up throughout pregnancy, ideally at a center that specializes in managing adults with congenital heart diseases, said Dr. Trigas, a congenital heart disease researcher at the German Heart Center in Munich.
Women who have undergone a TGA procedure “need to be informed that they can worsen” when pregnant, she added.
TGA is one of the most common congenital heart defects, accounting for about 5%–8% of congenital heart cases. If untreated, most children with TGA die before they are 2 years old, but with an atrial switch operation, most patients survive into at least their 30s.
To examine the effect and outcome of pregnancy in women with repaired TGA, Dr. Trigas and her associates reviewed the records of 60 pregnancies in 34 women who were followed at any one of three centers in Munich, Berlin, and Zurich. A total of 20 women had a history of isolated TGA as infants, and 14 had complex TGA that included other complications. Their average age at TGA repair was 19 months, with the latest done at 14 years. Their average age at first pregnancy was 25 years, ranging from 16 to 34 years. Their average age at the last pregnancy was 27 years; the oldest woman was 35 years old. The average duration of follow-up was almost 5 years.
Prior to pregnancy, 28 women were in functional class I, 5 were in class II, and 1 woman did not have her functional class documented in her records. Pregnancy led to class deterioration in seven women, but none of the women died during pregnancy.
Serious cardiac events during pregnancy included two cases of decompensation, and two other decompensation episodes that required resuscitation during delivery. Right ventricular dysfunction progressed in five patients. Tricuspid valve regurgitation progressed in three patients. Subpulmonary valve obstruction progressed in one woman and a new obstruction appeared in another. Systemic venous obstruction progressed in one woman, and three women developed new baffle leaks.
Obstetric complications occurred during 26 pregnancies, and included premature contractions in 9, vaginal bleeding in 5, dyspnea in 5, and premature rupture of membranes in 4.
Forty-four of the pregnancies resulted in term deliveries, and there were 16 abortions; 11 were miscarriages and 5 were induced. Births occurred at 29–42 weeks of gestation, with a median of 39 weeks. Sixteen deliveries were normal vaginal deliveries, 4 involved the use of forceps or suction assistance, and 24 were by cesarean section. Eleven deliveries were premature, at less than 37 weeks' gestation. The average birth weight was 2,910 g, with a range of 910–4,160 g. Three infants were born at less than 1,500 g. None of the infants had a congenital heart defect at birth.
Delivery emergencies included a need for resuscitation because of cardiac arrest in two women, and one case of cardiac and renal failure at 8 weeks post partum.
These women need careful follow-up throughout pregnancy, ideally at a specialized center. DR. TRIGAS