Comparison of different quantification methods of late gadolinium enhancement in patients with hypertrophic cardiomyopathy

Aim: There is no consensus regarding the technique of quantification of late gadolinium enhancement (LGE). The aim of the study was to compare different methods of LGE quantification in patients with hypertrophic cardiomyopathy (HCM). Methods: Cardiac magnetic resonance was performed in 33 patients with HCM. First, LGE was quantified by visual assessment by the team of experienced readers and compared with different thresholding techniques: from 1SD to 6SD above mean signal intensity (SI) of remote myocardium, above 50% of maximal SI of the enhanced area (full-width at half maximum, FWHM) and above peak SI of remote myocardium. Results: LGE was present in 25 (78%) of patients. The median mass of LGE varied greatly depending on the quantification method used and was highest with the utilization of 1SD threshold [75.5 g, interquartile range (IQR): 63.3-112.3 g] and lowest for FWHM method (8.4 g, IQR: 4.3-13.3 g). There was no difference in mass of LGE as assessed with 6SD threshold and FWHM when compared to visual assessment (p = 0.19 and p = 0.1, respectively); all other thresholding techniques provided significant differences in the median LGE size when compared to visual analysis. Results for all thresholds, except FWHM were significantly correlated with visual assessment with the strongest correlation for 6SD (rho = 0.956, p < 0.0001). Conclusions: LGE quantification with the use of a threshold of 6SD above the mean SI of the remote myocardium provided the best agreement with visual assessment in patients with HCM.