Predictive value of quantitative ventilation perfusion lung scintigraphy in lung transplantation.

Objectives: Lung transplantation is the definitive option for end-stage pulmonary disease. Although bilateral lung transplants are preferred, increasing demand and shortage of availability has led to use of unilateral transplants. Pre-operative quantitative ventilation/perfusion scintigraphy is an established parameter for lung function. Often the worse lung is transplanted first to minimize risk to the patient. This retrospective study compared outcomes of unilateral vs bilateral transplants in our patient population. It also evaluated outcomes of worse-first vs. better-first bilateral lung transplants.

Methods: One hundred sixty-five patients (59 F, 105 M), age range 31.7-78.0 years and mean age 64.3 years underwent lung transplantation. Patients presented with restrictive (102), obstructive (36), or combined (26) lung disease. All patients underwent ventilation/perfusion lung scans following IV administration of 4 mCi Tc99m-MAA and inhalation of 10 mCi Xe-133 and pulmonary function tests (PFTs) prior to surgery. These were compared to PFTs 2-weeks and 3-months post-transplant. Ten patients deceased due to medical or surgical complications.

Results: There were 101 bilateral and 63 unilateral transplants. Only 11 patients were discharged on home oxygen. Both groups made significant improvement in PFTs at 2 weeks and 3 months (p<0.0001). When comparing pre- and post-op FEV1 %predicted between the bilateral and unilateral group, the bilateral group made greater improvement at 2 weeks (p<0.0001) and 3 months (p<0.001). However there was no difference in FVC % predicted between the groups at 2-weeks (p=ns) and 3-months (p=ns). Within the bilateral group we found no difference between transplanting the worst-lung first and the better-lung first with PFTs at 2-weeks (p=ns) or 3-months (p=ns).

Conclusion: Both bilateral and unilateral lung transplant patients experienced significantly improved lung function. Importantly, the bilateral group made greater improvement than the unilateral group. Within the bilateral group there was no difference in lung function improvement from transplantation of the worse lung first vs. the better lung first as defined by ventilation/perfusion scintigraphy. Research Support: N/A