Hiroyuki Toh1, Shumpei Mori2, Yu Izawa1, Hiroshi Fujita1, Keisuke Miwa1, Masataka Suzuki1, Yu Takahashi1, Takayoshi Toba1, Yoshiaki Watanabe3, Atsushi K Kono3, Justin T Tretter4, Ken-Ichi Hirata1. 1. Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan. 2. UCLA Cardiac Arrhythmia Center, UCLA Health System, David Geffen School of Medicine at UCLA, Suite #46-119C, 650 Charles E. Young Dr. South, Los Angeles, CA 90095, USA. 3. Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Japan. 4. Department of Pediatrics, Heart Institute, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA.
Abstract
AIMS: Mitral annular disjunction is fibrous separation between the attachment of the posterior mitral leaflet and the basal left ventricular myocardium initially described in dissected hearts. Currently, it is commonly evaluated by echocardiography, and potential relationships with mitral valve prolapse and ventricular arrhythmia have been suggested. However, controversy remains as its prevalence and extent have not been fully elucidated in normal living subjects. METHODS AND RESULTS: Systolic datasets of cardiac computed tomography obtained from 98 patients (mean age, 69.1 ± 12.6 years; 81% men) with structurally normal hearts were assessed retrospectively. Circumferential extent of both mitral leaflets and disjunction was determined by rotating orthogonal multiplanar reconstruction images around the central axis of the mitral valvar orifice. Distribution angle within the circumference of the mitral valvar attachment and maximal height of disjunction were quantified. In total, 96.0% of patients demonstrated disjunction. Average distribution angles of the anterior and posterior mitral leaflets were 91.3 ± 9.4° and 269.8 ± 9.7°, respectively. Average distribution angle of the disjunction was 105.1 ± 49.2°, corresponding to 39.0 ± 18.2% of the entire posterior mitral valvar attachment. Median value of the maximal height of disjunction was 3.0 (1.5-7.0) mm. Distribution prevalence map of the disjunction revealed characteristic double peaks, with frequent sites of the disjunction located at the anterior to antero-lateral and inferior to infero-septal regions. CONCLUSION: Mitral annular disjunction is a rather common finding in the normal adult heart with bimodal distribution predominantly observed involving the P1 and P3 scallops of the posterior mitral leaflet. Published on behalf of the European Society of Cardiology. All rights reserved.
AIMS: Mitral annular disjunction is fibrous separation between the attachment of the posterior mitral leaflet and the basal left ventricular myocardium initially described in dissected hearts. Currently, it is commonly evaluated by echocardiography, and potential relationships with mitral valve prolapse and ventricular arrhythmia have been suggested. However, controversy remains as its prevalence and extent have not been fully elucidated in normal living subjects. METHODS AND RESULTS: Systolic datasets of cardiac computed tomography obtained from 98 patients (mean age, 69.1 ± 12.6 years; 81% men) with structurally normal hearts were assessed retrospectively. Circumferential extent of both mitral leaflets and disjunction was determined by rotating orthogonal multiplanar reconstruction images around the central axis of the mitral valvar orifice. Distribution angle within the circumference of the mitral valvar attachment and maximal height of disjunction were quantified. In total, 96.0% of patients demonstrated disjunction. Average distribution angles of the anterior and posterior mitral leaflets were 91.3 ± 9.4° and 269.8 ± 9.7°, respectively. Average distribution angle of the disjunction was 105.1 ± 49.2°, corresponding to 39.0 ± 18.2% of the entire posterior mitral valvar attachment. Median value of the maximal height of disjunction was 3.0 (1.5-7.0) mm. Distribution prevalence map of the disjunction revealed characteristic double peaks, with frequent sites of the disjunction located at the anterior to antero-lateral and inferior to infero-septal regions. CONCLUSION: Mitral annular disjunction is a rather common finding in the normal adult heart with bimodal distribution predominantly observed involving the P1 and P3 scallops of the posterior mitral leaflet. Published on behalf of the European Society of Cardiology. All rights reserved.
Authors: Sadie Bennett; Jacopo Tafuro; Marcus Brumpton; Caragh Bardolia; Grant Heatlie; Simon Duckett; Paul Ridley; Prakash Nanjaiah; Chun Shing Kwok Journal: Echo Res Pract Date: 2022-07-13
Authors: Sanne A Groeneveld; Feddo P Kirkels; Maarten J Cramer; Reinder Evertz; Kristina H Haugaa; Pieter G Postema; Niek H J Prakken; Arco J Teske; Arthur A M Wilde; Birgitta K Velthuis; Robin Nijveldt; Rutger J Hassink Journal: J Am Heart Assoc Date: 2022-08-05 Impact factor: 6.106