1 3 Heart Vessels DOI 10.1007/s00380-015-0670-4 ORIGINAL ARTICLE Prognostic significance of late gadolinium enhancement quantification in cardiac magnetic resonance imaging of hypertrophic cardiomyopathy with systolic dysfunction Akira Funada 1 · Hideaki Kanzaki 1 · Teruo Noguchi 1 · Yoshiaki Morita 2 · Yasuo Sugano 1 · Takahiro Ohara 1 · Takuya Hasegawa 1 · Hiromi Hashimura 2,3 · Hatsue Ishibashi-Ueda 3 · Masafumi Kitakaze 1,4 · Satoshi Yasuda 1 · Hisao Ogawa 1 · Toshihisa Anzai 1 Received: 18 December 2014 / Accepted: 20 March 2015 © Springer Japan 2015 95 % confidence interval = 1.23–2.15, p < 0.001). LVEF was inversely related to the extent of LGE (r = -0.44; p = 0.002) and was also an independent predictor of adverse cardiac events. Risk decreased with LVEF (haz- ard ratio = 0.68/10 % increase in LVEF, 95 % confidence interval = 0.51–0.91, p = 0.010). The Akaike information criterion evaluating the fit of a model demonstrated that the extent of LGE was a better independent predictor of MACE than LVEF (Akaike information criterion = 172.20 and 178.09, respectively).The extent of LGE was a good inde- pendent predictor of adverse cardiac events and reflected mortality and morbidity more precisely than LVEF in HCM with systolic dysfunction. Keywords Hypertrophic cardiomyopathy · Cardiac magnetic resonance · Late gadolinium enhancement · Prognosis Introduction Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiovascular disease. HCM is widely regarded as being associated predominantly with hyperdynamic left ventricular (LV) systolic function and has a generally benign clinical course, specifically a 1 % annual mortal- ity rate, little or no disability, and normal life expectancy in almost all patients [1–5]. LV myocardial fibrosis, a hall- mark of HCM, has been implicated in promoting heart failure (HF) as well as risk of sudden arrhythmic death [6, 7]. Risk stratification in HCM is still largely limited by relatively low positive predictive values of classical clini- cal risk factors, due in part to low mortality rates, because the clinical markers of myocardial fibrosis have not been defined [8–11]. Recently, late gadolinium enhancement Abstract Hypertrophic cardiomyopathy (HCM) with systolic dysfunction carries a poor prognosis. Although late gadolinium enhancement (LGE) on cardiac magnetic res- onance is associated with adverse cardiac events in HCM and is inversely related to left ventricular ejection fraction (LVEF), it is unknown whether LGE or LVEF more accu- rately predicts adverse cardiac events in HCM with sys- tolic dysfunction. We retrospectively assessed the extent of LGE with a threshold of 6 standard deviations in 46 con- secutive HCM patients with systolic dysfunction defined as LVEF <50 % (average 35 ± 12 %) who underwent cardiac magnetic resonance (35 males, mean age 59 ± 14 years). They were followed up over 1755 ± 594 days. The com- posite adverse cardiac events end point included car- diovascular death, lethal arrhythmia, cardioembolic stroke, and unplanned heart failure hospitalization. LGE was detected in all patients, and the mean extent was 30 ± 15 %. Twenty-nine patients developed adverse car- diac events. Multivariate Cox proportional hazard analysis revealed the extent of LGE as a good independent pre- dictor of adverse cardiac events. Risk increased with the extent of LGE (hazard ratio = 1.62/10 % increase in LGE, * Akira Funada a-funada@e-mail.jp 1 Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center, 5-7-1 Fujishiro-dai, Suita, Osaka 565-8565, Japan 2 Department of Radiology, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan 3 Department of Pathology, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan 4 Department of Clinical Research and Development, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan