Contrast echocardiography remains positive after treatment of pulmonary arteriovenous malformations.

Study Objectives: Pulmonary arteriovenous malformations (PAVMs) in patients with hereditary hemorrhagic telangiectasia (HHT) can cause hemorrhage, stroke, and cerebral abscess. Therapy consists of transcatheter embolotherapy (TCET) to occlude the PAVMs. Contrast transthoracic echocardiography (TTE) can be used to screen for PAVMs, but little is known about the performance of contrast TTE after TCET has been performed. Our objective was to determine the effect of the successful performance of TCET on the performance of contrast TTE, specifically, in what proportion of patients the findings of contrast TTE normalized or remained positive after the performance of TCET.
Design: Retrospective chart review.
Setting: HHT clinic at university teaching hospital.
Patients: Patients who have undergone TCET for the treatment of PAVMs.
Interventions: Patients were screened for PAVMs with a chest radiograph (CXR), oxygen shunt test (OST), and contrast TTE. Pulmonary angiography was recommended for patients with any positive findings on a screening test. PAVMs > or = 3 mm were occluded by TCET. Contrast TTE, OST, and CXR were performed approximately 1 month later. The results of contrast TTE before and after patients underwent TCET were compared.
Measurements and Results: Thirty-nine patients underwent contrast TTE prior to undergoing TCET, and 29 patients underwent contrast TTE both prior to and after undergoing TCET. In all patients, TTE findings were positive prior to TCET. All PAVMs with feeding vessels > or = 3 mm were successfully occluded based on completion angiography. After TCET, 48% of patients had no detectable residual PAVMs, and the remainder had small (ie, < 3 mm) residual PAVMs. Of the 29 patients, 90% had positive contrast TTE findings after undergoing TCET. In the subset of patients who had no residual PAVMs on the completion angiography, 80% had positive contrast TTE findings after undergoing TCET.
Conclusions: In most patients, contrast TTE findings remain positive after they undergo TCET, even in patients without residual PAVMs seen on angiography. This may reflect residual PAVMs that are too small to visualize using angiography. These findings have important implications for the follow-up and management of HHT patients.