Fatal lung scan in a case of pulmonary hypertension due to obliterative pulmonary vascular disease.

A young woman with pulmonary hypertension due to sclerodermatous pulmonary vascular disease died immediately following the injection of macroaggregated albumin labeled with 99-TC for a perfusion lung scan. Review of the literature suggests that patients with chronic pulmonary hypertension due to an obliterative pulmonary vascular disease are at risk of developing a serious reaction to perfusion lung scanning. Important factors which predispose to an adverse reaction to lung scanning are the size and dose of macroaggregated albumin particles in relation to the total cross-sectional area of the pulmonary vascular bed and a critical arteriolar lumen size.