The Role of Echocardiography in the Evaluation of Pulmonary Arterial Hypertension

The evaluation of pulmonary arterial hypertension (PAH) requires a multimodality approach that combines invasive and noninvasive imaging studies to ensure accurate diagnosis and classification. Given the complexity of the hemodynamic relationships between the left heart, pulmonary circulation, and right heart, the diagnosis of PAH is often a challenging task. Right heart catheterization is the gold standard for diagnosis, providing the hemodynamic information that defines the disease. Nonetheless, echocardiography continues to be a valuable tool in the approach to the patient with suspected PAH. Echocardiographic assessment generates a wealth of information about the response of the right heart to elevated pulmonary pressures and provides essential diagnostic and prognostic data to the clinician. Numerous measurements can be used to identify alterations in right heart morphology, pressure, and function; although each variable in isolation may have little utility, meaningful information is revealed when multiple parameters are considered together. In this article, we will review the echocardiographic measurements employed in assessment of the right heart and seek to clarify the role of echocardiography in the diagnostic workup of PAH.