Cardiopulmonary transit time measured on dynamic rubidium cardiac PET/CT is a predictor for pulmonary hypertension

Abstract Background Cardiopulmonary transit time (CPTT), the time for blood to circulate from the right to the left ventricle can be assessed on dynamic Rubidium-82 ([ 82 Rb]) cardiac PET/CT. Given its association with cardiac and pulmonary function, CPTT holds potential as a screening marker for pulmonary hypertension. This study investigated the relationship between CPTT and echocardiographic markers of cardiac function, as well as its association with pulmonary hypertension. In this retrospective single-center study, 111 patients (72 male, 39 female) referred for [ 82 Rb]RbCl-PET/CT and echocardiography within 31 days were included. CPTT, normalized to heart rate (NCPTT), was calculated from peak right and left ventricular [ 82 Rb] activity and examined in relation to patient characteristics and echocardiographic parameters, which were further used to categorize left and right ventricular systolic dysfunction, left ventricular diastolic dysfunction, and signs of elevated pulmonary arterial pressure. Results Prolonged NCPTT was significantly associated with lower left ventricular ejection fraction and increased body weight (p