Pulmonary Arterial Hypertension is a rare disease of the pulmonary circulation that produces narrowing of small pulmonary arteries, increasing of pulmonary vascular resistance and right ventricular failure. We studied the associated metabolic reprogramming in lung and heart tissues, which is essential for disease progression, in a mouse model of hypoxia induced PAH. Lung and heart metabolism were monitored by HR-MAS NMR spectroscopy and PET imaging. We identified an alteration in energetic and proliferative metabolism of the lungs. We also found a shift in energy metabolism in cardiac tissue.