While adenoviral delivery of a gene encoding mature VEGF-D has been shown to improve myocardial perfusion in pigs and has now advanced through phase I/IIa studies in patients with refractory angina (67, 68), elevated circulating levels of VEGF-D have been reported in patients with HF, atrial fibrillation, ischemic stroke, PAH, chronic thromboembolic pulmonary hypertension (CTEPH) and LAM (69–73). The gene discussed is VEGFD; the disease is pulmonary arterial hypertension.