Pulmonary arteriovenous malformations

Helical CT scan (HCT), a noninvasive method, can detect pulmonary arteriovenous malformations (PAVMs). Its sensitivity is superior to that of global digitalized angiography, but patients receive a significant dose of radiation during diagnostic HCT. We compared HCT to contrast-enhanced pulmonary magnetic resonance angiography (CEMRA), a new noninvasive radiation-free method, in the diagnosis of PAVMs.

Five consecutive patients with PAVMs underwent HCT, CEMRA, and pulmonary artery digital subtraction angiography (PADSA). CEMRA was performed during the pulmonary arterial phase of an IV bolus of gadolinium. PADSA was performed during the embolization procedure. All images were examined for PAVMs. The site and size of aneurysms were specified, as well as the diameter of the vascular pedicles.

Thirty PAVMs were detected by CEMRA and 38 by HCT. All 20 PAVMs at least 5 mm in diameter and 10 of the 18 PAVMs < 5 mm in diameter identified on HCT were also identified by CEMRA. Whatever the site, all PAVMs with a feeding artery diameter of at least 3 mm (ie, PAVMs with clinical consequences) were detected by CEMRA. No false-positive results were obtained with CEMRA. CEMRA therefore had a sensitivity of 78% and a specificity of 100%.

CEMRA, a nonionizing and noninvasive procedure, has high sensitivity and specificity for the diagnosis of clinically relevant PAVMs.