Multimodal echocardiography in the diagnosis of masses localized to the proximal portions of pulmonary arteries.

Proximal pulmonary artery masses are exceedingly rare, and their diagnosis and therapy are important and challenging for clinicians. This study reviews our experience exploring the value of a combination of transthoracic echocardiography and contrast echocardiography for the differential diagnosis of proximal pulmonary artery masses. Between January 2018 and June 2021, 44 patients diagnosed with a mass attached to the major pulmonary artery and straddling the bilateral pulmonary arteries or pulmonary valve on transthoracic echocardiography were referred to this study. Contrast echocardiography was performed in 17 patients. Masses were diagnosed based on their site of attachment, shape, size, mobility, hemodynamic consequences on transthoracic echocardiography, and tissue perfusion on contrast echocardiographic perfusion imaging. Pathological data were collected from medical records and analyzed. The most frequent location of proximal pulmonary artery masses was the major pulmonary artery trunk. Twelve patients underwent complete mass resection, whereas nine patients underwent percutaneous pulmonary artery biopsy puncture and had a pathological diagnosis. Another 24 patients were confirmed with the validation methods. Contrast echocardiography has good sensitivity and specificity for differentiating thrombi from pulmonary artery sarcomas (PAS). The mass types were distributed as follows: thrombi (19, 43%), PAS (15, 34%), metastatic tumors (6, 14%), vegetations (3, 7%), and primary benign lesions (1, 2%). The majority of proximal pulmonary artery masses were thrombi or PAS. A combination of transthoracic echocardiography and contrast echocardiography offers advantages in the early identification of proximal pulmonary masses and provides clinically important information about the characteristics of masses, especially for differentiating thrombi from PAS.