Multimodality Imaging, Diagnostic Challenges and Proposed Diagnostic Algorithm for Noncompaction Cardiomyopathy

Noncompaction cardiomyopathy (NCCM) is a clinical-patho-anatomic entity, disputably believed to result from abnormal arrest in embryonic endomyocardial morphogenesis. Introduction of echocardiography has led to recognition of NCCM for the first time in 1984. During almost 35 years of technical improvements in imaging alongside a more dedicated research of NCCM, more knowledge has developed alongside uncertainties concerning every aspect of the disease. In this chapter, we present the role of multimodality imaging in NCCM alongside diagnostic uncertainties and practical aspects on how to overcome these challenges. Limitations of the current diagnostic criteria will be reviewed. The inter-technique differences will be contrasted. Finally, future aspirations will be outlined in providing a more thoughtful appraisal towards NCCM diagnosis. There is paucity of data regarding NCCM due to the etiology, natural history, pathophysiology, heterogeneity of disease spectrum and phenotype-genotype overlap with other cardiac anomalies. There are three research aspects in the fields of NCCM: patho-anatomic studies, imaging studies, and genetic screening. Besides conventional echocardiography, imaging should include both structural (cardiac magnetic resonance imaging (MRI), cardiovascular computed tomography, contrast echocardiography and 3D echocardiography) and functional diagnosis such as deformation imaging. Moreover, it holds the promise of the detection of earliest stages of the disease. Currently, several efforts are underway including large registries as well as the use of novel imaging modalities in better understanding and diagnosis of NCCM. Genotype-phenotype studies for better risk stratification of sudden cardiac death are underway. Importantly, a clear patho-anatomic cut-off definition of NCCM should be the initial step towards a uniform imaging diagnosis.