Apical perfusion fraction as a predictor of short-term functional outcome following bilateral lung volume reduction surgery

Study objectives: To examine whether relative hypoperfusion to the apical o ne third of the lungs as determined by lung scintigraphy predicts a favorab le functional outcome following bilateral lung volume reduction surgery (LV RS). Methods: We performed a retrospective analysis of 128 patents who underwent bilateral LVRS. An apical perfusion fraction (AP%), defined as the percent age of total lung perfusion to the apical one third of both lungs, was deri ved for each patient by quantitative scintigraphy technique. Pulmonary func tion testing and 6-min walk test (6MWT) data were obtained preoperatively a nd 3 to 6 months postoperatively. Results: The mean (+/-SD) improvement in FEV1 was 309 +/- 240 mL, 209 +/- 2 93 mL, and 116 +/- 224 mL for patients with an AP% of less than or equal to 10%, 11 to 20%, and > 20%, respectively (p = 0.01, analysis of variance [A NOVA]). The likelihood of experiencing an increase in FEV1 greater than or equal to 200 mL was 68% for those with an AP% less than or equal to 10% but only 31% for those with an AP% > 20%. Preoperative and postoperative 6MWT data were available for 109 of 128 patients. Improvement was 250 +/- 252 fe et, 205 +/- 299 feet, and 77 +/- 200 feet for patients with AP% less than o r equal to 10%, 11 to 20%, and > 20%, respectively (p = 0.04, ANOVA). While 50% of those with an AP% less than or equal to 10% improved their 6MWT by greater than or equal to 180 feet, only 21% of those with an AP% > 20% did so. Conclusion: This retrospective analysis suggests that quantification of api cal perfusion by nuclear scintigraphy assists in predicting the likelihood of short-term functional improvement after LVRS.