Eur Respir J 53 (1): 1801913, 2019. doi: 10.1183/13993003.01913 - 2018 Pathophysiology of Pulmonary Hypertension Pathophysiologic mechanisms that cause pulmonary hypertension include Increased pulmonary vascular resistance Increased pulmonary venous pressure Increased pulmonary venous flow due to congenital heart diseases Increased pulmonary vascular resistance is caused by obliteration of the pulmonary vascular bed and / or by pathologic vasoconstriction.