LUNG DYSFUNCTION IN SUBJECTS LONG-TERM AFTER SURGERY FOR CONGENITAL HEART DEFECTS (CHD). EFFECT OF SURGICAL STRATEGY AND A NATURAL COURSE

Frequency and severity of lung dysfunction long-term after surgery for CHD depends on preoperative hemodynamics and peri-operative/post-operative course. We focused on effect of different surgical approach as well as influence of natural postoperative course on pulmonary function (PFT) abnormalities. 
We tested 58 children with transposition of the great arteries (TGA) operated on by switch operation (SWT-TGA), age of surgery 10.0 days (median) and 82 subjects after physiological (atrial) repair of TGA (AR-TGA), age of surgery 1.8 yrs (median). PFT was performed at the age of 9.7 yrs (median) after SWT and 8.5 yrs (median) after AR-TGA, resp. (Group 1). Group 2 consists of 159 pts who were tested serially: 82 pts 8.5 yrs and later again 13.0 (medians) yrs after total correction of TOF as well as 77 pts 8.5 yrs and 16.3 (medians) yrs after AR-TGA. The same protocol (i.e., static lung volumes by body-plethysmography, indices of lung elasticity and airway patency) was used for both groups.
Stiffer lung, i.e., lung recoil at TLC level (Pst100) 128±37 and 137±37% predicted was detected in SWT-TGA and AR-TGA, resp. Neither lung volume restriction nor peripheral airway obstruction was also found in any subgroup (Group 1). In Group 2 a serial evaluation of PFT long-term after repair showed only mild differences in both subgroups over the years: lung size and airway patency persist without deterioration. The lungs became more compliant (Pst100 decreased by 12.0 and 4.3% of initial value, resp., NS) while hyperinflation increased.
Lung dysfunction found long-term after SWT-TGA was less prominent. PFT in two different cyanotic CHD revealed over the years similar abnormalities. We suggest preoperative pulmonary hemodynamics and long-term natural course as probably major factors influencing lung development regardless successful heart surgery.
Support 00064203/6404