An unexpected and unusual cause of pulmonary hypertension in a patient with hypersensitivity pneumonitis: a partial anomalous pulmonary venous connection causing pulmonary artery hypertension.

Partial anomalous pulmonary venous connection (PAPVC) occurs when any pulmonary vein, but not all, drains directly into the right atrium or its venous tributaries. PAPVC can very rarely present as an individual cause of pulmonary artery hypertension. Here we are presenting the case of a 41-year-old farmer with a history of exertional dyspnea for the past 3 years, which increased over 6 months.