In patients with pulmonary arterial hypertension eNOS levels are reduced. Retinopathy is often secondary to diseases such as diabetes or hypertension. Hypertension and edema due to congestive heart failure. Right heart failure is the principal consequence of severe pulmonary arterial hypertension. Moreover, these biochemical parameters strongly correlated to the severity of pulmonary arterial hypertension. Screening for cardiovascular risk factors, such as smoking, dyslipidemia, hypertension, and alcoholism is helpful. PAH is diagnosed after exclusion of other possible causes of pulmonary hypertension. Pleural effusion may also be noticed, which is due to pulmonary venous hypertension. They may also be used to treat pulmonary arterial hypertension (PAH). Tocilizumab is being studied for pulmonary arterial hypertension (PAH). Other symptoms include hypertension, and hypoglycemia. Evidence for pregnancy-induced hypertension and preeclampsia was considered inconclusive. Pulsatile tinnitus may also be an indication of idiopathic intracranial hypertension. Imatinib was initially thought to have a potential role in the treatment of pulmonary hypertension. PRA is measured specially in case of certain diseases that present with hypertension or hypotension.