Am. J. Respir. Crit. Care Med., Vol 151, No. 2, 02 1995, 534-540.
Persistent hyperinflation after heart-lung transplantation for cystic fibrosis
I Guignon, M Cassart, PA Gevenois, C Knoop, M Antoine, JC Yernault and M Estenne
Department of Chest Medicine, Erasme University Hospital, Brussels, Belgium.
We have measured static lung volumes after heart-lung transplantation (HLT)
in seven patients with cystic fibrosis (CF) (Group 1), three patients with
chronic hyperinflation due to diseases other than CF (Group 2), and six
patients with primary pulmonary hypertension (PPH) (Group 3). Total lung
capacity was within normal limits at 1 yr after surgery in all patients.
Similarly, FRC was within the normal range in Groups 2 and 3. On the other
hand, patients with CF showed a persistent increase in FRC; at 1 yr after
HLT, FRC averaged 4.13 +/- 0.52 L compared with a predicted value of 3.20
+/- 0.23 L (p < 0.01). The postoperative static pressure-volume curve of
the lung in the patients with CF was superimposed on the predicted one,
suggesting that the increased FRC originated in the chest wall. Additional
studies with computerized tomographic scans demonstrated that the rib cage
anteroposterior diameter at FRC averaged 12.1 +/- 1.6 cm in patients with
CF, 9.5 +/- 1.2 cm in patients with PPH, and 9.4 +/- 0.7 cm in a group of
healthy subjects matched with the patients with CF (p < 0.01). We
conclude that after HLT, patients with CF show persistent hyperinflation
due to rib cage expansion along the anteroposterior dimension. This shape
change may represent a structural adaptation that occurs in response to
chronic pulmonary hyperinflation acquired during rib cage growth.
