1、A Case of Hypertrophic Cardiomyopathy RegressionFrom Circ Cardiovasc Imaging.2015;8:Kebed,MD,Mayo Clinic CaseAn 18-year-old man was referred for evaluation after amarkedly abnormal ECG was discovered at a professional hockey scouting event.He was otherwise healthy and asymptomaticHe had no family hi
2、story of cardiomyopathies or sudden unexplained death.ECGUCGA contrast enhanced transthoracic echocardiogram showed apical HCM with a maximal LV wall thickness of 24 mm and spade-like appearance LV chamber size and systolic function were normal without dynamic obstruction.Diastolic function assessme
3、nt showed indeterminate diastolic function gradeMRIthe apex and anterior septum measured 25 and 13 mm,First pass perfusion was normal,but postcontrast images demonstrated patchy areas of late gadolinium enhancement suggestive of fibrosisMRIHolterExercise ECG and 24-hour Holter monitor showed no vent
4、ricular arrhythmiasgenetic testingOn genetic testing,a de novo HCM associated mutation in MYH7-encoded myosin heavy chain gene at position 530(p.Ile530Val)was identified.The patients parents and 2 siblings,all phenotype negative for HCM,tested negative for the mutation.The patient was counseled on t
5、he natural history of HCM and the risk of sudden death with competitive athletics.None of the standard sudden death risk markers were present at the initial evaluation,and therefore there was no indication for an implantable cardioverter defibrillator.The patient discontinued his rigorous athletic t
6、raining,but continued to lead a relatively active lifestyleHe was seen for follow-up 14 months after the initial diagnosis.Repeat cardiac MRI showed complete resolution of the LV hypertrophy with maximal wall thickness of 10 mmat the apex However,the patchy areas of late gadolinium enhancement were
7、unchanged On repeat noncontrast echocardiogram,maximum thickness was 12 mm at the apex.The ST depression and deeply inverted T waves were less prominent on his repeat ECGECGMRIBecause of the regression of hypertrophy after detraining and negative genetic testing in family members,genetic testing was
8、 repeated to exclude the possibility of a false-positive result,but he was again found to be genotype positiveHe continued to be asymptomatic until 16 months afterthe diagnosis when he developed presyncope and tachy-palpitations.An event recorder demonstrated episodes of supraventricular tachycardia
9、 and nonsustained ventricular tachycardia.Given his symptoms,documented nonsustained ventricular tachycardia,and late gadolinium enhancement on cardiac MRI,an implantable cardioverter defibrillator was implantedSince the implantable cardioverter defibrillator placement,now 5 years ago,the patient ha
10、s done well with no appropriate implantable cardioverter defibrillator discharges.On his most recent echocardiogram(6 years and 2 months since diagnosis),maximum thickness remained 12 mm at the apex.These images demonstrate a novel case of LV hypertrophy regression after detraining in a patient with
11、 clinical HCM and an HCM-associated mutation.There are limited data supporting regression of LV hypertrophy with pharmacotherapy and surgical relief of outflow tract obstruction,but to our knowledge none on regression after detraining.At initial diagnosis,the extreme ECG changes,marked asymmetrical
12、hypertrophy,late gadolinium enhancement,and genetic mutation were all consistent with an underlying pathological process rather than physiological adaptation.However,it is possible the patient has both athletic adaptation to intense training which has currently regressed and HCM.Alternatively,this c
13、ase may challenge the existing dogmathat regression is only seen in physiological remodeling such as athletes heart and that HCM phenotypic conversion is not altered by exogenous loads on the heart.Overall,it is of clinical importance to distinguish HCM and athletes heart because of the differing re
14、commendations and prognosis.The potential lifestyle restrictions for HCM have not only physicalramifications but also psychological and financial,as in this patient who was a professional athlete prospectBackgroundHypertrophic cardiomyopathy(HCM)is a genetic cardiovascular disease characterized by a
15、 hypertrophied,nondilated left ventricle(LV)in the absence of other causes.HCM is relatively common and is one of the most common causes of sudden death in athletes.Distinguishing HCM from athletes heart is of critical importance.BackgroundHCM is genotypically and phenotypically heterogenous.The differential diagnosis for HCM includes physiological remodeling seen in athletes heart.Distinguishing HCM from athletes heart is of critical importance.THANKS FOR LISTENING
