# Left Ventricular Non-Compaction Cardiomyopathy-Still More Questions than Answers
## 4 Diagnostic Methods
### Magnet Resonance Imaging
The measurements were performed in end-distable. The ability of cardiac CMR to assess the right ventricle compared to echocardiography makes it a robust method for evaluating RV in suspicious NC cases. Unfortunately, there are fewer works available that deal with RV and NC. Because of the particular anatomy of the right ventricle, it is not easy to distinguish between pathologic and anatomically normal trabeculations. This right ventricle property leads to underestimating reported RV involvement in NC. [50] Otherwise, radiologic determination of a noncompaction-to-compaction ratio in the right ventricle is difficult (Figure 2E). Dilatation of the RV could be a supportive fact [51]. LGE has not yet been recognized as a final criterion for NC, but it provides dozens of crucial supporting information [52]. Because arrhythmia is the leading cause of death in LVNC patients, recognizing underlying fibrosis is very important [53]. A correlation between the amount of LGE and LVNC severity course was found. The patients with higher LGE were found to have more advanced diseases [54]. \begin{table}
\begin{tabular}{c c c c c} \hline
**Author** & **Method** & **Diagnostic Criteria** & **Cardiac Phase** & **Cut-Off** \\ \hline \multirow{8}{*}{[PERSON] [47]} & \multirow{8}{*}{ECHO} & Ratio of compacted and & & \\  & & non-compacted & & \\  & & endocardi. Presence of & & \\  & & at least 3 trabeculations & & \\  & & protruding in the left & & \\  & & ventricle apically from & & \\  & & papillary muscle, presence & & \\  & & of the blood flow between & & \\  & & trabeculations. & & \\ \hline \multirow{8}{*}{[PERSON] [33]} & \multirow{8}{*}{ECHO} & Ratio of compacted and & & \\  & & non-compacted & & \\  & & endocardi. Absence of & & \\  & & coexisting cardiac & & \\  & & abnormalities, the presence & & \\  & & of deep trabeculations, & & \\  & & which are filled with blood & & \\ \hline \multirow{2}{*}{[PERSON] [48]} & \multirow{2}{*}{MDCT} & Ratio of compacted and & & \\  & & non-compacted & All 17 segments, & \\  & & endocardi in at least 2 & end diastole & \\  & & or more segments & & \\ \hline \end{tabular}
\end{table} 
Table 2: _Cont._Our protocol for analysis of a patient with excessive trabeculation in CMR is as follows:  
Retrospectively gated LV 2-, 3-, and 4-chamber long-axis (LAX) single-slice and short-axis oblique (SAO) base-to-apex stack cine bSSFP sequences with 6-8 mm slice thickness, 2 mm slice gap, pixel size \(\leq\) 1.8 \(\times\) 1.8 mm\({}^{2}\), and a temporal resolution \(<\) 50 ms.  
A typical examination procedure for non-compaction patients includes 2-chamber (1 slice), 3-chamber (3 slices), and 4-chamber (3 slices) long-axis views as well as a short-axis stack covering the entire left/right ventricle (12-16 slices, no gap) using cine steady-state free precession acquisitions (TR/TE/flip angle = 2.7 ms/1.35 ms/42\({}^{\circ}\)) to assess cardiac function and morphology. Spatial resolution should be approximately 1.5 \(\times\) 1.5 \(\times\) 8 mm\({}^{3}\) and at least 30 cardiac phases per cardiac cycle to achieve an acquisition time of 30-35 ms per cardiac phase (assuming a heart rate of approximately 60 beats per minute). Parallel imaging techniques should restrict breath-hold periods to less than 12 s (Figures 2 and 3). How do we measure? 1. We find the maximum manifestation of trabeculae in the short and long axes in end-diastole. If the non-compaction to compaction ratio \(>\) 2.3, consider the diagnosis of LVNC. 2. We calculate trabeculated mass including the blood pool at end-diastolic. A percentage of \(>\)20% of trabeculated mass confirms the diagnosis (Figure 5). Figure 5: CMR examination, short-axis cine bSSFP image of the mid-cavity LV. Prominent hypertra-speculation in a 20-year-old male with a history of ADPKD and LVNC phenotype. Measurement of the whole myocardial mass: (**A**) Determination of epicardial contours and endocardial contours at the NC myocardium border for measurement of whole myocardial mass.