Unexplained pulmonary hypertension in pediatric patient is a diagnostic challenge. The natural history as well as management depends upon etiology of pulmonary hypertension. Despite newer insights in pathophysiology and management strategies, the outcome of pulmonary veno-occlusive disease remains dismal. The author's report a case of 12-year-old girl who presented with severe pulmonary hypertension. Stepwise evaluation and CT angiographic assessment in the index case led to definitive diagnosis of pulmonary veno-occlusive disease. This case highlights the role of cardiac imaging in localising site of pulmonary hypertension. It is important for health care professionals involved in care of patients with pulmonary hypertension to make correct diagnosis of pulmonary veno-occlusive disease for better prognostication as well as to avoid therapeutic mishaps.