Can pulmonary arterial hypertension develop quickly? found out i have mild pah?

Pulmonary hypertensi: Pulmonary artery hypertension is usually secondary to chronic pulmonary disease or left sided heart disease and develops gradually. Primary or idiopathic pulmonary hypertension has no obvious causes, is difficult to diagnose early due to lack of symptoms early on and may thus appear to have a rather sudden onset. A pulmonologist or cardiologist can advise you further.