Hemodynamic estimation of chronic cor pulmonale by Doppler echocardiography. Clinical value and comparison with other noninvasive imaging techniques.

Pulmonary arterial pressure (PAP) represents an important prognostic factor in patients affected by chronic obstructive pulmonary disease (COPD). A noninvasive diagnostic approach is offered by several imaging techniques, such as chest X-ray, nuclear medicine, real-time sonography, color Doppler US, CT and MRI. However, at present a quantitative assessment of PAP is not achieved with reasonable precision with any of these techniques. Tricuspid regurgitation can be estimated by continuous wave Doppler but it may be difficult in patients with COPD. On the contrary, the severity of pulmonary hypertension can be accurately assessed with pulsed Doppler echocardiography from the subxiphoid region, using a general purpose US device. Nineteen adult patients with COPD were studied by duplex-Doppler from an oblique subxiphoid approach and right heart catheterization. The study was diagnostic in all cases with quality Doppler recordings. A significant relationship was found between AcT and pulmonary mean or systolic pressure at rest. An accurate prediction of PAP in COPD is possible by means of pulsed-Doppler also in low-grade hypertension. This technique is considered a simple and reliable adjunct to the noninvasive evaluation of COPD and represents a satisfactory alternative to the classical parasternal approach preferred by cardiologists but often not suitable for emphysematous patients. Radiologists who routinely use a general purpose US device are encouraged to try this new technique in the study of heart disease.