Right ventricular fat imaging with cardiac MRİ in asymptomatic healthy volunteers: Relationship with age, gender and bmi

Purpose: To demonstrate the relationship between right ventricular myocardial fat and gender, BMI and age in healthy and asymtomatic individuals. Materials and Methods: 107 healthy and asymptomatic subjects evaluated for right ventricular intramyocardiyal fat infiltration. ECG triggered cardiac MRI performed with Siemens Avanto 1,5 T in all subjects. Intramyocardial T1W hyperintense fat foci confirmed with fat saturated T1W images. Each subject evaluated for myocardial fat, number of involved segments, most frequent involved segments, associated wall motion abnormalities. Right ventricular and RVOT end diastolic diameters and right ventricle ejection fraction measured to assesment of right ventricular dysfunction. Relationship between all obtained data and gender, age and BMI was investigated. Results: Intramyocardial fat was detected in 65 of 107 subjects. 49 of subjects with fat were female. Fat was detected %45,7 of male and %68,1 of female subjects. There is statiscally significant positive relationship between rihgt ventricular myocardial fat deposition and female gender. BMI <30 was in 34, >30 was in 73 subjects. %38.2 of BMI<30 group and %71.2 of BMI>30 group has fat in myocardium. There is statiscally significant positive relationship between right ventricular myocardial fat deposition and obesity. Fat was observed most frequently in midventricular lateral, apicoanterior, midventricular anterior segments, and less frequently seen in RVOT. There is statiscally significant positive correlation between number of infiltrated segments and BMI. There was no difference in EF, RV ED and RVOT ED diameters between subjects with and without fat. Also RV ED and RVOT ED diameters were normal in both groups. Conclusion: Compared to CT assesment for myocardial fat content, MRI is more consistent with histopathologic results of autopsy series. Thus, MRI is more sensitive to fat content than CT. BMI and female gender have significant positive relationship with right ventricular myocardial fat. However, right ventricular functional measurements were normal. Therefore, in subjects with right ventricular myocardial fat, diagnosis of ARVD or other pathologic fat infiltration causes should be avoided unless accompanied by wall motion abnormalities or functional impairment.