Revisiting the prevalence and diversity of localized thinning of the left ventricular apex

Prevalence of Left Ventricular Myocardial Crypts in Japanese Patients

Objective Myocardial crypts are congenital abnormalities associated with hypertrophic cardiomyopathy (HCM) and other conditions. This study assessed the prevalence of myocardial crypts in Japanese patients. Methods Myocardial crypts were evaluated in a consecutive series of 300 patients (13-92 years old) who underwent computed tomography angiography (CTA) because of clinical suspicion of ischemic heart disease. Results We found a myocardial crypt incidence of 9.7% (29 patients) in our study population, with multiple crypts observed in 2.3% (7 patients). Among these, myocardial crypts were found in 2 out of 8 (25%) patients with hypertrophic cardiomyopathy (HCM), 1 of which was apical-type HCM. In patients with a single crypt (22 patients), the most common location of the crypt was at the left ventricular apex (16/22 patients, 72.7%), followed by the inferior wall (5/22 patients, 22.7%) and the interventricular septum (1/22 patients, 4.6%). Conclusion The incidence of myocardial crypts observed in our study aligns with that reported in previous studies, although the most common location among the Japanese population was the left ventricular apex.

Prevalence and extent of mitral annular disjunction in structurally normal hearts: comprehensive 3D analysis using cardiac computed tomography

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.