Early Detection of Pulmonary Arterial Hypertension Using Cardiac Magnetic Resonance Imaging

Inclusion Criteria: Consecutive patients aged ≥ 18 years with PAH as dictated by a comprehensive examination and echocardiography will be included for enrollment. Exclusion Criteria: * Age \< 18 years * Pregnancy * Mechanical ventilation * Acute or chronic renal failure (creatinine clearance \< 30 ml/min or requiring renal replacement therapy) * Inability to perform MRI (i.e. claustrophobia, severe obesity (\> 150 kg), device incompatible with MRI) * Significant arrhythmia that precludes adequate ECG-gating for the MRI (i.e. atrial fibrillation with highly variable cycle lengths) * Prior heart or lung transplantation * Left ventricular systolic (ejection fraction \< 50%) or diastolic failure (based on Framingham criteria for heart failure with preserved ejection fraction) * Significant left-sided valvular disease (≥ moderate aortic stenosis, mitral stenosis, aortic regurgitation, mitral regurgitation) or prior valve surgery