Imaging the right heart pulmonary circulation unit: Insights from advanced ultrasound techniques.

The right heart pulmonary circulation unit (RH-PCU) is a key determinant of prognosis in several cardiorespiratory diseases. Although right heart catheterization is considered the gold standard for pulmonary hemodynamic assessment, a comprehensive cardiovascular ultrasound approach is an essential step in the diagnostic-prognostic clinical pathway of patients with suspect or overt pulmonary hypertension. The exponential development of advanced ultrasound techniques (strain, 3-dimensional echocardiography and lung ultrasound) has led to new insights into the evaluation of RH-PCU structure and function, overcoming some limitations of standard Doppler echocardiography. In the near future, exercise Doppler echocardiography may become a useful technique for detecting a latent stage of pulmonary hypertension and for evaluating right ventricular contractile reserve.