Imaging of the heart in pulmonary hypertension

Abstract

Pulmonary hypertension (PH) is a disease of the pulmonary arteries resulting in a progressive increase in pulmonary vascular resistance, ultimately leading to right ventricular failure and death. It is a rare disease with a poor prognosis. The functional capacity of the right ventricle (RV) is a major prognostic determinant in PH. Our understanding of RV performance in PH has been hindered by the lack of techniques that give a reliable picture of right ventricular morphology and function. There have been recent major advances in our understanding of the mechanism of disease development, in the diagnostic process and in the treatment of PH. There are now three classes of medications that are effective in the treatment of PH: prostanoids, endothelin receptor antagonists and phosphodiesterase-5 inhibitors. Therapeutic advances in the management of PH have reinforced the requirement for non-invasive, accurate and reproducible methods of assessment to act as 'end-points' to measure the effects of treatment. It is our opinion that the most useful 'end-point' would be one that evaluates right heart morphology and function. We introduce and discuss the techniques currently used to image the heart in patients with PH. Imaging modalities discussed include echocardiography, radionuclide ventriculography, cardiac computed tomography and cardiac magnetic resonance (CMR) imaging focusing on the rapidly evolving technique of CMR imaging.