Reversal of diffuse patchy pattern in lung perfusion scan in a case of severe pulmonary arterial hypertension

Abstract

A diffuse patchy pattern in the perfusion scan of the lung is a hallmark of severe pulmonary arterial hypertension (PAH). However, the mechanisms of this unique pattern remain uncertain. We here present the case of a 19-year-old woman with severe PAH who demonstrated reversal of the diffuse patchy pattern with improvement of pulmonary blood flow within a month after upfront triple combination therapy. Our case is a first report showing reversibility of diffuse patchy pattern by a short-term treatment in severe PAH. These findings suggest the possibility that the mechanisms underlying the diffuse patchy pattern may involve reversible vasoconstriction in addition to remodeling of small pulmonary arteries.

Keywords: Diffuse patchy pattern; Pulmonary arterial hypertension; Upfront combination therapy.