招請講演　Part 2：妊娠・出産の医学心理社会的問題<br>Pregnancy and delivery in women with congenital heart disease

Cardiologist, Thoraxcenter, Erasmus MC, Rotterdam, the Netherlands
Jolien W. Roos-Hesselink

Heart disease is present in 0.5-1% of all pregnant women and accounts for 10-15% of all maternal mortality.^{1, 2)} There are no signs of decline of this incidence over the past decades. The majority of women with heart disease want to become pregnant and heart disease is no bar to sexual activity. However, the physiological adaptation to pregnancy is the most rapid and profound change that a woman’ s body will undergo in her lifetime (Fig. 1 and 2). When pregnancy occurs in women with pre-existing heart disease these changes might be potentially life threatening.
The risk of developing cardiac complications in pregnancy is strongly influenced by the type of heart defect, postoperative sequellae, and residual lesions. In the landmark study of Siu et al., predictors of adverse maternal outcome in 599 women with mainly congenital heart disease were determined and a risk score was developed (Table 1). ^{3, 4)} However, the danger of some high-risk conditions (such as mechanical valve prosthesis, cyanotic lesions, pulmonary hypertension) might be underestimated by this scoring system. The ACC/AHA and ESC guidelines for cardiovascular disease during pregnancy define high-risk lesions, in addition to left-sided heart obstructions and severely impaired left ventricular function, as pulmonary hypertension, cyanotic heart disease and mechanical prosthetic valves.⁵⁾ Important cardiac complications are seen in 11% of patients with congenital heart disease, most often clinically significant heart failure and arrhythmias. Obstetric complications do not appear to be more prevalent, but in complex congenital heart disease, premature delivery rates are high, and more children are born small for gestational age. The offspring mortality is high throughout the spectrum and is related to the relatively high rate of premature delivery and recurrence of congenital heart disease. Whether pregnancy itself has an irreversible effect on ventricular function in patients with heart disease is unclear. In a small prospective study regarding long-term effects of pregnancy on cardiac function, Guedes et al. found an irreversible right ventricular dysfunction after pregnancy in patients with atrial repair for transposition of the great arteries.⁶⁾
Cardiac workload peaks during delivery. Epidural anesthesia has been suggested to reduce cardiovascular stress. No convincing data favouring either vaginal delivery or caesarean section have been reported. However, Caesarean section leads to more blood loss at delivery and potentially greater fluxes in blood pressure.
References
1) Steer PJ, et al: Heart disease and pregnancy. London: RCOG; 2006
2) Robson SC, et al: Am J Physiol. 1989; 256: H1060-1065
3) Siu SC, et al: Circulation 1997; 96: 2789-2794
4) Siu SC, et al: Circulation 2001; 104: 515-521
5) Bonow RO, et al: Circulation 2006; 114: e84-231
6) Guedes A, et al: J Am Coll Cardiol 2004; 44: 433-437
7) Drenthen W, et al: J Am Coll Cardiol 2007 (in press)