CASES FROM ANZ

Members from Australian and New Zealand (and regional affiliates) are invited to submit cases for consideration for publication on the ANZCMR website. This is your chance to showcase your best and most interesting cases to your colleagues thoughout out region! 

"Non-Compaction Cardiomyopathy"

This months case has been submitted from:

Dr Sylvia SM Chen and Dr Ronald J Dick, The Epworth Hospital, Melbourne, Victoria. 

Case History:

A 60 year old man presented with dyspnoea and mild chest tightness on exertion. He has well controlled type 2 diabetes mellitus, and no other cardiac risk factors or significant medical history.

Coronary angiography showed normal coronary arteries, but poor left ventricular (LV) function of 36%, a high EDP of 28mmHg and there also appeared to be some LV trabeculation on ventriculography. An initial diagnosis of non-ischaemic dilated cardiomyopathy was made.

Subsequent echo study showed possible apical LV trabeculation, and the patient was referred for a cardiovascular magnetic resonance (CMR) study for further evaluation.

CMR findings:

CMR showed dilated and significantly trabeculated left and right ventricles (Figure 1) with poor function, LVEF 27% and RVEF 38%. There was progressive increase in LV trabeculation from the lower middle third of the LV to its apex, where trabeculation was particularly heavy in the apical inferior wall. The diastolic ratio of non-compacted to compacted myocardium at this point was >2.3 (Figure 2).  


Figure 1 - Four chamber image showing dilated left and right ventricles with trabeculation in the RV ‘apex’, and progressive trabeculation from mid-apical LV.

 

Figure 2 - Ventricular short axis at the lower mid to apical regions showing heavy trabeculation in both ventricles.

Early post contrast study did not show any thrombus, but in the late phase, there was mid wall fibrosis in the basal-mid septal, anterior and in the lateral walls (Figure 3).

Figure 3 - Delayed enhancement images at the basal, mid and apical short axis levels showing midwall enhancement predominantly - at the base, in the anteroseptal, anterolateral, inferolateral and part of the inferior wall; at mid ventricle, in the anteroseptal and lateral walls; and at the apical lateral wall. 

Conclusion:

A diagnosis of non-compaction cardiomyopathy affecting both ventricles was made. Anti-heart failure therapy with medications was instituted and an ICD was inserted. Subsequent screening of his children also showed LV non-compaction cardiomyopathy in his daughter.

Perspective:

Non-compaction cardiomyopathy is a rare disorder and is primarily a genetic cardiomyopathy characterised by prominent tabeculae and deep intertrabecular recesses. CMR is the ideal imaging modality for this as not only is it able to provide high quality diagnostic images, but it is also able to asses for thrombus, and for myocardial fibrosis.  Myocardial fibrosis can occur in both the compacted myocardium or/and in the trabeculations of the non-compacted myocardium [1]. CMR regions of delayed enhancement have previously been confirmed as fibrosis in both compacted and non-compacted myocardium on histology [2]. The presence and extent of fibrosis independently predict poor LVEF, and importantly, fibrosis may also occur in the asymptomatic patient [3] with non-compaction cardiomyopathy. CMR is therefore imperative for the evaluation of myocardial fibrosis and hence in the longer term follow up of patients who may have been asymptomatic or do not have fibrosis at first diagnosis and CMR study.

References:

1. Jassal DS, Nomura CH, Neilan TG, Holmvang G, Fatima U, Januzzi J, Brady TJ, Cury RC. Delayed enhancement cardiac MR imaging in noncompaction of left ventricular myocardium. J Cardiovasc Mag Res 2006;8:489-491.

2. Chaowu Y, Li L, Shihua Z. Histopathological features of delayed enhancement cardiovascular magnetic resonance in isolated left ventricular noncompaction. J Am Coll Cardiol 2011;58:311-312.

3. Nucifora G, Aquaro GD, Pingitore A, Masci PG, Lombardi M. Myocardial fibrosis in isolated left ventricular non-compaction and its relation to disease severity. Eur J Heart Fail 2011;13:170-176