Current perspectives on imaging modalities in the diagnosis and management of pulmonary hypertension

Pulmonary hypertension (PH) is a heterogeneous syndrome in which elevated pulmonary arterial pressure arises from diverse parenchymal, thromboembolic, and vasculopathic processes. Right heart catheterization remains the hemodynamic reference standard; however, clinicians increasingly turn to noninvasive imaging to triage candidates for invasive confirmation, to determine the disease phenotype, and to monitor the response to interventions such as pulmonary endarterectomy or balloon pulmonary angioplasty. In routine practice, chest computed tomography (CT), together with echocardiography and ventilation-perfusion (V/Q) scintigraphy, underpins the detection of chronic thromboembolic PH and provides pragmatic structural biomarkers, including the main pulmonary artery size relative to that of the ascending aorta, right ventricular remodeling, and lung parenchymal disease. Dual-energy CT expands anatomic assessment with iodine perfusion maps, whereas magnetic resonance imaging (MRI)-based techniques are used to quantify right ventricular function, flow, and lung perfusion without ionizing radiation. Phase-resolved functional lung MRI and 4D-flow MRI show promise for low- or non-contrast assessment of perfusion defects and conduit hemodynamics. Dynamic chest radiography, a flat-panel x-ray technique, has diagnostic performance comparable to that of V/Q scanning for chronic thromboembolic disease at a fraction of the radiation dose. Molecular imaging with positron emission tomography captures metabolic stress in the right ventricle and inflammatory or proliferative activity within the pulmonary vasculature; early data suggest its prognostic utility, although standardization is pending. We propose a pragmatic framework that preserves catheterization for diagnostic confirmation and hemodynamic problem-solving, while leveraging minimally invasive techniques for longitudinal follow-up and early trajectory detection in pulmonary vascular and parenchymal phenotypes.