Abstract 1637: Difference of Pulmonary Arterial Microvasculature in Patients with Pulmonary Hypertension Using Scanning Electron Microscope
Background and Objectives: Pulmonary vascular diseases (pulmonary arterial hypertension: PAH, pulmonary veno-occlusive disease: PVOD and pulmonary capillary hemangiomatosis: PCH) are well-known diseases that cause pulmonary hypertension (PH). However, the differences of structural characteristics of pulmonary microvasculature in these diseases have not been elucidated enough. We examined the morphological differences among these diseases by methacrylate resin (Mercox) perfusion using scanning electron microscope.
Methods and Results: Ten lung samples were 8 patients with PH and 2 control subjects without PH. These were obtained at lung transplantations or autopsies. Microvascular corrosion replicas were made by Mercox perfusion from the pulmonary artery. Pathological diagnosis revealed 5 PAH, 2 PVOD and 1 PCH in patients with PH. In PAH samples, small arteries or arterioles showed twisted and tortuous courses, but such vessels were not observed in samples from control, PVOD and PCH. Binary branching was observed in control, but not in PVOD and PCH. In PVOD and PCH, several branching was commonly observed. Moreover, the loss of capillary network and the disruption of arterioles were more severe in samples from PVOD and PCH patients than in samples from PAH patients.
Conclusion: Pulmonary microvascular morphology is seriously different among the type of underlying diseases in PH patients.