Repetitive out of hospital cardiac arrests following pregnancy: a case report of an unfortunate presentation of mitral annular disjunction

Abstract

Background Mitral annular disjunction (MAD) is an under-recognized cause of arrhythmic sudden cardiac death, especially in young women. The relation between MAD and the occurrence of arrhythmia during pregnancy has not yet been explored. We would like to stress the importance of careful echocardiographic examination and the vulnerable peripartum period. Case summary A 29-year-old woman survived an out of hospital cardiac arrest 4 months after delivery of her first child. The diagnosis was not clear and an implantable cardioverter-defibrillator (ICD) as secondary prevention was implanted. Her second pregnancy and delivery were uneventful. The 12-lead electrocardiogram demonstrated sinus rhythm with right bundle branch block, ventricular extra systoles (premature ventricular contractions), and a right superior axis, i.e. origin in the inferolateral basal left ventricle. Transthoracic 2D echocardiography showed myxomatous mitral valve disease with moderate mitral valve insufficiency with normal left and right heart dimensions and function. However, 4 weeks after delivery she experienced a sudden syncope at home. Implantable cardioverter-defibrillator reading revealed primary ventricular fibrillation, induced by a ventricular premature beat (VPB), terminated with a successful ICD shock. A frame-by-frame echocardiographic analysis of the mitral valve using biplane echocardiographic analysis allowed diagnosis of MAD with detachment of the root of the annulus from the posterolateral ventricular myocardium during systole. Conclusion Mitral annular disjunction is an under-recognized cause of arrhythmic sudden cardiac death. Biplane echocardiographic analysis of the mitral annulus can identify MAD and as such may help for risk stratification and sudden cardiac death prevention. Careful follow-up is necessary especially during pregnancy and the postpartum period.

Mitral annular disjunction identified peripartum: A case highlighting key features of a recently classified syndrome

“…In line with the current literature, this case features a young female with numerous factors that are characteristic of MAD 3–5 . Together with a MAD distance of 8.5 mm by TTE, the associated factors include palpitations, 2 syncope, 3 low ejection fraction (51 ± 5%), 2 chest pain and ventricular arrythmia 6 .…”

“…Disjunction diameter is best measured from a zoomed para‐sternal long‐axis (PLAX) view 2,3,5 (see Figure 3). However, it can also be measured at apical 3 chamber view and apical 4 chamber view 2 .…”

“…Pickelhaube's sign is a high velocity tissue Doppler spike of >16 cm/s above the baseline in mid‐systole at the lateral mitral annulus 5,6 . (an example is shown in Figure 4).…”

“…In line with the current literature, this case features a young female with numerous factors that are characteristic of MAD. [3][4][5] Together with a MAD distance of 8.5 mm by TTE, the associated factors include palpitations, 2 syncope, 3 low ejection fraction (51 ± 5%), 2 chest pain and ventricular arrythmia. 6 The precise location at which MAD occurs is yet to be agreed upon: one report indicates that MAD can be a three-dimensional circumferential continuum, 2 another reports that it only exists only at the insertion of the posterior leaflet, 7 while others suggest that it is either posteromedial (PM) or anterolateral (AL) with a higher prevalence and severity with PM MAD.…”

“…Pickelhaube's sign is a high velocity tissue Doppler spike of >16 cm/s above the baseline in mid-systole at the lateral mitral annulus. 5,6 (an example is shown in Figure 4). Pickelhaube's sign quantifies the obscure hypermobility of the mitral annulus that is a typical F I G U R E 3 MAD in parasternal long axis view (PLAX) at end ventricular systole.…”