Preliminary Analysis Of Influencing Factors Of Myocardial Thickness In Patients With Apical Hypertrophic Cardiomyopathy

Backgrounds and Objectives The myocardial thickness is closely related to the prognosis in patients with hypertrophic cardiomyopathy.AHCM is an unique subtype of hypertrophic cardiomyopathy.Investigating changes of myocardial thickness over time is important for evaluating progression and prognosis of the disease.In this study,we retrospectively analyzed the change rate of apical thickness in patients with AHCM during a follow-up by echocardiography,to explore the development of myocardial thickness and its related influencing factors in patients with AHCM for providing more information about diagnosis and treatment.Methods A total of 32 patients diagnosed as AHCM(21 males and 11 females,median age64 years)were consecutively enrolled in this study by 24-118 months’ follow-up,where18 patients(56.25%)were diagnosed as AHCM at first visit(group A,Apmax ≥ 15 mm,ABR > 1.5),and 14 patients(43.75%)had apical thickness of 15 mm at follow-up(group B).The clinical information,follow-up duration,echocardiography findings(cardiac size,function,apical thickness)and electrocardiogram data were collected.The difference between the last and the first apical thickness(mm)and its change rate(V-Apmax)during the follow-up were calculated.Results 1.A total of 32 patients showed precordial deep T-wave(≥0.05 mv)inversion on ECG,17(53.1%)of whom had giant negative T-wave(≥1.0 mv).There were no significant differences between patients with and without GNT(p=0.214).2.Compared to echocardiography findings at the first visit,patients at the last visit had significantly greater Apmax and LAD(Apmax:20.53±4.09 mm vs.17.19±4.98 mm,p=0.000).3.The total increase of apical thickness and its thickening velocity(V-Apmax)in group B were higher than those in group A.(V-Apmax:group B:0.83±1.81 mm/ year vs group A: 0.40±0.33 mm/year,p=0.012).4.V-Apmax was negatively correlated with age and apical thickness at initial diagnosis.Conclusion The progression of apical wall thickness in AHCM patients is likely to be related to the age of onset and the stage of disease,where apical wall thickening faster in young patients or in the early stage of the disease,and may slowdown in the elder or when the wall thickness increases to a certain extent.The above conclusions need to be confirmed by follow-up in a larger patient cohort.