Brief Answer:
As mentioned

Detailed Answer:
Hi, thanks for using Healthcaremagic.

I went through your query and understood your concerns.

Immunohistochemistry analysis has shown that viral antigens are distributed primarily within the endothelium of vessels in the pulmonary microvasculature.
Functional impairment of vascular endothelium is central to the pathogenesis of HPS. antigens in heart do cause myocardial depression. Antigens in endothelium attract many inflammatory cells. Resulting in increased permeability of vessels with extravasation on fluid in pulmonary system,

Hope I answered your query. Feel free to ask further related query.

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