US Echocardiography Transesophageal With IV Contrast TEE with IV agitated saline contrast material is not routinely used to diagnose PAVM. Contrast-enhanced TEE maybe helpful to locate a PAVM based on the excellent visualization of the 4 pulmonary venous ostia as veins drain into the left atrium. Based on the visualization of contrast material emanating from a particular pulmonary vein, the location of the PAVM in that venous territory can be confirmed [38,40]. In the presence of multiple PAVMs, the usefulness of this imaging modality in identifying the location of the PAVMs may be limited. US Echocardiography Transthoracic Resting There is no role for TTE in the resting phase for evaluation of PAVM. It does allow evaluation of intracardiac shunts and assessment of cardiac function [38]. US Echocardiography Transthoracic With IV Contrast TTCE is an essential diagnostic test for patients suspected of having a PAVM. TTCE with agitated saline has a 98% to 99% sensitivity and a 67% to 91% specificity for detecting PAVMs [41]. The microbubbles are visualized after 3 to 8 cardiac cycles in the left atrium after initial opacification of the right chambers in patients with an intrapulmonary shunt [1]. TTCE does not provide any information regarding the size and location of the PAVM. Based on the appearance of the bubbles in the left atrium a semiquantitative grading system has been developed Pulmonary Arteriovenous Malformation (PAVM) [42,43]. The grades are defined as 0 with no opacification, grade 1 with <30 bubbles, grade 2 with moderate filling, and grade 3 with complete opacification of the left atrium. The grading system correlates well with the diagnosis of PAVM, with higher grades associated with larger shunts and cerebral complications [41,44,45]. Usefulness of the grading system to predict treatment of PAVM demonstrates that grades 2 and 3 have a positive predictive value of 0.21 (95% CI, 0.05-0.36) and 0.87 (95% CI, 0.79-0.99), respectively [44].
Pulmonary Arteriovenous Malformation PAVM . US Echocardiography Transesophageal With IV Contrast TEE with IV agitated saline contrast material is not routinely used to diagnose PAVM. Contrast-enhanced TEE maybe helpful to locate a PAVM based on the excellent visualization of the 4 pulmonary venous ostia as veins drain into the left atrium. Based on the visualization of contrast material emanating from a particular pulmonary vein, the location of the PAVM in that venous territory can be confirmed [38,40]. In the presence of multiple PAVMs, the usefulness of this imaging modality in identifying the location of the PAVMs may be limited. US Echocardiography Transthoracic Resting There is no role for TTE in the resting phase for evaluation of PAVM. It does allow evaluation of intracardiac shunts and assessment of cardiac function [38]. US Echocardiography Transthoracic With IV Contrast TTCE is an essential diagnostic test for patients suspected of having a PAVM. TTCE with agitated saline has a 98% to 99% sensitivity and a 67% to 91% specificity for detecting PAVMs [41]. The microbubbles are visualized after 3 to 8 cardiac cycles in the left atrium after initial opacification of the right chambers in patients with an intrapulmonary shunt [1]. TTCE does not provide any information regarding the size and location of the PAVM. Based on the appearance of the bubbles in the left atrium a semiquantitative grading system has been developed Pulmonary Arteriovenous Malformation (PAVM) [42,43]. The grades are defined as 0 with no opacification, grade 1 with <30 bubbles, grade 2 with moderate filling, and grade 3 with complete opacification of the left atrium. The grading system correlates well with the diagnosis of PAVM, with higher grades associated with larger shunts and cerebral complications [41,44,45]. Usefulness of the grading system to predict treatment of PAVM demonstrates that grades 2 and 3 have a positive predictive value of 0.21 (95% CI, 0.05-0.36) and 0.87 (95% CI, 0.79-0.99), respectively [44].