noncompaction of ventricular myocardium ( nvm ) is considered as an unusual cause of cardiomyopathy . dense trabecular meshwork and deep intertrabecular recesses are seen on the ventricle wall.1 ) etiology of nvm is thought to be due to arrest of myocardial morphogenesis.2 ) the prevalence of left ventricular noncompaction is about 0.01% in adults and 0.14% in pediatric patients.3)4 ) the most common site of involvement is the left ventricle ( lv ) , with right ventricular involvement being reported in a few cases.5)6 ) in this report , we present a case with noncompaction of the right ventricle ( rv ) . magnetic resonance imaging ( mri ) and cardiac computed tomography angiography ( ccta ) demonstrated morphological and functional abnormalities of the rv . a 72-year - old male presented mild chest discomfort and palpitation sense with effort . in his medical history , he had hypertension , hyperlipidemia , and diabetes mellitus . he had no relevant history of familial heart disease or history of smoking . on admission , his blood pressure was 157/85 mm hg with pulse rate at 84 beats / min . transthoracic echocardiogram reveal - ed a hypertrabeculated and spongiform appearance of the right ventricular apical segment . a color doppler echocardiographic examination revealed the presence of blood flow in the deep intertrabecular recesses . on four chamber view , end - diastolic basal diameter of the rv was measured at 4 cm ( normal < 4.2 cm ) . rv systolic function was observed as normal with tricuspid annular plane systolic excursion of 2 cm and myocardial performance index of 0.35 . ccta revealed two stents located at the proximal segment of the left anterior descending artery and one stent located at mid - segment of the circumflex artery . additionally , a prominent trabecular meshwork and deep intertrabecular recesses were observed at the apex of the rv . noncompacted thickness ( nc ) of the rv in diastole was 22.2 mm at the apical level with compacted thickness ( c ) of 2.6 mm ( nc / c ratio 8.5 ) ( fig . 1a ) . wall hypokinesis was observed at the mid and distal anterior wall segments of the lv . noncompacted wall segments of the rv were well depicted on four - chamber static image of the cine - mri ( fig . it is being reported with increasing frequency as a cause of ventricular failure in adults and children . it has been described in association with congenital heart defects , most often with outflow obstructive lesions or coronary anomalies . however , no factor could explain the arrest of the development of the myocardial structure ( isolated form).7 ) isolated ventricular non - compaction ( ivnc ) is considered as unclassified cardiomyopathy.1 ) the pathogenesis of ivnc is thought to be an arrest in endomyocardial morphogenesis . approximately between fetal week 5 to week 8 , intertrabecular spaces are compressed , resulting in compaction from the base towards the apex and from epicardium to endocardium . it has been reported that myocardial noncompaction could present as acquired disease.8 ) since the coronary arterial circulation is normal in ivnc , extramural myocardial blood supply is not likely the cause.9 ) the cause and pathogenesis of acquired disease still remains unknown , but a few hypothesis have been proposed to explain the etiopathogenesis 10 ) : 1 ) noncompaction results from an insufficient attempt of hypertrophy of the ventricular myocardium ; 2 ) noncompaction results from an attempt to enlarge the endocardial surface to move large volumes with less contractility in volume overload ; 3 ) noncompaction results from multiple dissections of the myocardium caused by decreased adhesion of cardiac cells.10 ) we considered the case as an isolated form . however , participation of both ventricles and rarely isolated involvement of the rv can be seen . noncompaction was reported to affect exclusively lv in a series of 34 adults.3 ) rv noncompaction has been depicted only in a few cases of newborns with congenital heart defects and in adult patients.11)12 ) mri has been proposed to be an important diagnostic tool in nvm . the ratio of noncompacted to compacted myocardium ( nc / c ratio ) has been reported as a diagnostic criterion . a diastolic nc / c ratio > 2.3 was reported to have high diagnostic accuracy for distinguishing pathological left ventricular noncompaction from other degrees of trabeculation observed in healthy , dilated , and hypertrophied hearts.13 ) however , no specific criterion has been proposed for the diagnosis of noncompaction of rv . this is likely due to its small number of cases and less performed ccta and mri for diagnosis in the past . in our case , arrhythmias , heart failure , and thromboembolic events may be seen as morbidity during long - term follow - up . heart failure is caused by systolic and diastolic dysfunction.3 ) in summary , ccta and mri are ex - cellent diagnostic tools for nvm , especially in noncompaction of rv .
noncompaction ventricular myocardium is an unusual cause of cardiomyopathy . 
 it is association with congenital heart defects , most often with outflow obstructive lesions or coronary anomalies . 
 however , no factor could explain the arrest of development of myocardial structure ( isolated form ) . 
 the pathogenesis of isolated noncompaction is thought to be an arrest in endomyocardial morphogenesis . 
 it has been reported that myocardial noncompaction could present as acquired disease . 
 the most common site of involvement is the left ventricle , with right ventricular involvement being reported in a few cases . in this report , we present a case with noncompaction of the right ventricle ( rv ) . cardiac computed tomography angiography and magnetic resonance imaging demonstrated morphological abnormalities of the rv .