Teaching Case

A one-year-old female patient (body surface area 0.36 m2), was presented with rapid breathing and rapid heart rate. Echo was performed. It showed dilated heart, poor function, normal origin of the coronary arteries and abnormal contour of the left ventricle. Subsequently cardiac magnetic resonance imaging (CMRI) was recommended.

CMRI was performed as previously described [1]. Ventricular volumes were considered dilated compared to the published normal cardiac end diastolic volumes [1]. CMRI showed severe global left ventricular (LV) hypokinesia, severe systolic LV impairment (ejection fraction (EF)=10%) with markedly dilated normalized LV and right ventricular (RV) end diastolic volumes (LVEDVI=500ml/m2, RVEDVI=83 ml/m2) (Fig. 1, 2). The RV had mildly impaired function (RVEF=45%). An associated large posterior basal LVA; detected by echo as an abnormal contour, appeared in CMRI as an abnormal aneurysmal contour bulge (Fig. 2) of systolic dyskinesia. During the cine images, a whorl turbulent flow appeared in the LV cavity (Fig. 1). The patient’s heart rate during CMRI was about 140 beats/min. Delayed enhanced CMRI (DE-CMRI) showed no evidence of sub-endocardial enhancement. A calculated moderate mitral regurgitation (LV stroke volume – stroke volume measured in the aorta) and mild pericardial effusion were also found (Fig. 2).

Background: Left ventricular aneurysm (LVA) in patients with IDCM is a rarely reported entity [2-4]. In about 50 % of cases with DCM, the exact cause of ventricular dilatation is unknown; and is referred to as IDCM [5, 6]. Criteria to diagnose IDCM include ejection fraction < 0.45, and a left ventricular end diastolic dilatation of > predicted value corrected for age and BSA. Simultaneously, other causes of DCM have to be excluded; such as metabolic, toxic, endocrine, viral, congenital heart diseases (CHD) or systemic illnesses [5, 6].

Clinical Perspective: Different hypotheses have described the pathogenesis of LVA in IDCM, however, they are still poorly understood [2].

Imaging Perspective: The global hypokinesia, poor systolic functions and ballooning of the LV are diagnostic to DCM. Other causes of DCM were excluded through the patient's history, full clinical examination, imaging, and/or laboratory findings [5, 6]. The CMRI did not show any DE-MRI of any specific infiltrative process.
The key findings for LVA in IDCM include the location of the LVA (posterobasal) [2], severe dilatation of the LVEDVI compared to patients with DCM without LVA, markedly affected systolic functions [3] compared to patients with DCM without LVA, in absence of coronary abnormalities, indirectly identified in our case through absence of DE-MRI [3]. A 4D-flow may have been clearer in showing turbulent flow in the LV cavity during diastole. We do not have 4-D flow in our institute, which may be considered a limitation in our study.
Outcome: Due to the rarity of the case and the patient’s poor condition, an intense discussion between paediatric cardiologists and cardiothoracic surgeons took place in order to decide whether to send the patient to aneurysm resection or medical treatment. Based on CMRI findings of the aneurysm’s typical location being similar to that previously published in a few case reports, the final decision was sending the patient to medical treatment. Supportive treatment measurements were planned to control disease worsening as well as prevent complications such as heart failure and thromboembolism.
Take Home Message: Although the explanation is not well understood, one of the rare causes of LVA is IDCM. The whorl turbulent flow in the current case’s LV may support the previously published hypothesis of wall stress on the posterobasal wall [2]. The current case report supports other similar rare reports of LVA location in IDCM at the LV posterobasal wall, severe impaired LV systolic function [2] and markedly dilated LV [3].