Clinical Significance of Incidentally Detected Aneurysms of the Membranous Ventricular Septum in Adults by Multidetector Computed Tomography

Abstract

Although the clinical relevance of aneurysm of the membranous ventricular septum (AMVS) in adults is unclear, the frequency of AMVS detection has been increased because cardiac multidetector computed tomography has been widely adopted for the evaluation of coronary artery disease. Therefore, we aimed to assess the clinical significance of AMVS in a longitudinal study. In 30,120 adults with suspected coronary artery disease who underwent cardiac multidetector computed tomography in 3 hospitals, 52 patients with AMVS were retrospectively selected. We evaluated the clinical symptoms and electrocardiographic abnormalities (cross-sectional study) and the prevalence of embolic stroke (observational study) during a median 40-month (range 6 to 74months) observation period. For the assessment of embolic stroke, we excluded 9 patients with other explainable embolic sources. Conduction abnormalities were noted in 13 of 52 adults (25%) with AMVS on electrocardiography and embolic stroke occurred in 6 of 43 patients (14%). The mean age and the prevalence of hypertension were significantly higher in the embolic stroke group than in the event-free group (p <0.05). Thrombi were detected in the 11.6% of AMVS, which was significantly related with embolic stroke (p <0.05). The size and morphology did not change in 15 patients with serial follow-up images. In conclusion, our study suggests that AMVS in adults should not be ignored because AMVS may be related to conduction abnormality or embolic stroke, and it does not spontaneously resolve or diminish in size.