Procainamide-induced pulmonary fibrosis after orthotopic heart transplantation: a case report and literature review

A 33-year-old African-American woman was bridged to heart transplantation with a left ventricular assist device. She had a 14-month history of heart failure secondary to viral cardiomyopathy. The patient's refractory ventricular tachycardia was treated with intravenous procainamide owing to the patient's history of amiodarone-induced thyroiditis. After orthotopic cardiac transplant, she experienced prolonged respiratory failure. Serial computed tomography evaluation of the lung revealed diffuse bilateral ground-glass opacities and septal thickening. Bronchoscopies with tissue biopsies were performed with no conclusive results. Specimen samples displayed septal fibrosis with loose fibromyxoid tissue and some hobnail nodularities with no indication of granulomas, neutrophilic infiltration, malignancy, or fungal, viral, or bacterial growth. Histopathological evaluation of the lung wedge biopsy supported a diagnosis of pulmonary fibrosis and noted interstitial fibrosis with areas of focal alveolar hemorrhage and increased macrophage infiltration. Antinuclear body was found to be negative. After in-depth evaluation of the patient's medication history, procainamide was identified as the cause of the toxicity. As procainamide-induced lung fibrosis is relatively uncommon, we present this case to highlight procainamide's potential harm and the need for careful monitoring in postsurgical patients.