Left ventricular solid body rotation in non-compaction cardiomyopathy: A potential new objective and quantitative functional diagnostic criterion?

Background: Left ventricular (LV) twist originates from the interaction between myocardial fibre helices that are formed during the formation of compact myocardium in the final stages of the development of myocardial architecture. Since non-compaction cardiomyopathy (NCCM) is probably caused by intrauterine arrest of this final stage, it may be anticipated that LV twist characteristics are altered in NCCM patients, beyond that seen in patients with impaired LV function and normal compaction. Aims: The purpose of this study was to assess LV twist characteristics in NCCM patients compared to patients with non-ischaemic dilated cardiomyopathy (DCM) and normal subjects. Methods and results: The study population consisted of 10 patients with NCCM, 10 patients with DCM, and 10 healthy controls. LV twist was determined by speckle tracking echocardiography. In all controls and DCM patients, rotation was clockwise at the basal level and counterclockwise at the apical level. In contrast, in all NCCM patients the LV base and apex rotated in the same direction. Conclusions: These findings suggest that 'LV solid body rotation', with near absent LV twist, may be a new sensitive and specific, objective and quantitative, functional diagnostic criterion for NCCM.