Why does apical hypertrophic cardiomyopathy have a favorable outcome than non-apical types?:Cardiac magnetic resonance and
echocardiographic findings from 350patients with hypertrophic cardiomyopathy
Eun Kyoung Kim 1*,Sang-Chol Lee 1,Hye Bin Gwag 1,Sung-A Chang 1,Sung-Ji Park 1,Sung-Mok Kim 2,Yeon Hyeon Choe 2,Seung Woo Park 1
From 17th Annual SCMR Scientific Sessions New Orleans,LA,USA.16-19January 2014
Background
Apical HCM tends to have a favorable outcome com-pared to other types.The presence and extent of late gadolinium enhancement (LGE),reflecting myocardial fibrosis,is closely correlated with increased cardiac mor-tality and strongly associated with surrogates of arrhyth-mia and subsequent sudden cardiac death.This study sough to investigate the difference in cardiac magnetic resonance (CMR)and echocardiographic and clinical manifestations between apical hypertrophic cardiomyo-pathy (HCM)and non-apical HCM.
Methods
A total of 350consecutive patients diagnosed with HCM (mean age 54±12,278males)underwent CMR and echocardiography.Clinical characteristics including risk factors for sudden cardiac death were collected.Eighty-five patients were classified as apical type.On CMR,left ventricle (LV)volumetric parameters were measured,and the amount of LGE was calculated with gray-scale thresholds of 6SD above the mean signal intensity for normal remote myocardium and also expressed as a ratio against total LV volume.Echocardiographic evaluations included left atrial volume index (LAVI),mitral inflow pattern,tissue Doppler of mitral annulus and LV dimension.
Results
Patients with apical HCM were less likely to present with history of syncope (2.4%vs.10.2%,p =0.02)and have family history of sudden cardiac death than those with non-apical HCM (5.9%vs.15.8%,p =0.02).Functional class was also more favorable in apical HCM (frequency of NYHA class I;89.4%vs.66.8%,p <0.001).CMR volu-metric parameters were not different between the two groups except LV mass index (71.7±17.3vs.92.0±34.1,p <0.001).LGE was less frequently detected (87.1%vs.93.9%,p =0.04),and the amount of LGE was significantly smaller in apical HCM (7.0±6.0%vs.14.6±10.5%,p <0.001).The E/e level and LAVI were also lower in apical HCM patients (E/e;10.1±3.3vs.13.6±5.7,p <0.001and LAVI;40.4±20.8vs.45.9±16.9,p <0.001).
Conclusions
Apical hypertrophy shows relatively small burden of myo-cardial fibrosis and less severe diastolic dysfunction,and subsequently more favorable clinical manifestations in comparison with other HCMs.This may be one explana-tion of why most patients with apical HCM show a benign course of disease compared to non-apical HCM.Funding None.
Cardiology,Cardiovascular Imaging Center,Samsung Medical Center,Seoul,Korea,Republic of
Full list of author information is available at the end of the article
Kim et al .Journal of Cardiovascular Magnetic Resonance 2014,16(Suppl 1):P233
https://www.wendangku.net/doc/6710560271.html,/content/16/S1/P233
?2014Kim et al.;licensee BioMed Central Ltd.This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://www.wendangku.net/doc/6710560271.html,/licenses/by/2.0),which permits unrestricted use,distribution,and reproduction in any medium,provided the original work is properly cited.The Creative Commons Public Domain Dedication waiver (https://www.wendangku.net/doc/6710560271.html,/publicdomain/zero/1.0/)applies to the data made available in this article,unless otherwise stated.
Authors ’details 1
Cardiology,Cardiovascular Imaging Center,Samsung Medical Center,Seoul,Korea,Republic of.2Radiology and Center for Imaging Science,
Cardiovascular Imaging Center,Samsung Medical Center,Sungkyunkwan University School of Medicine,Seoul,Korea,Republic of.Published:16January 2014
Kim et al .Journal of Cardiovascular Magnetic Resonance 2014,16(Suppl 1):P233
https://www.wendangku.net/doc/6710560271.html,/content/16/S1/P233
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