Study on thoracic skeletal muscle characteristics of Danon disease and hypertrophic cardiomyopathy based on cardiovascular magnetic resonance imaging / 中国医师杂志

Objective:To apply cardiovascular magnetic resonance (CMR) to quantitatively evaluate the morphology and tissue characteristics of thoracic skeletal muscle (TSM) in patients with Danon disease and hypertrophic cardiomyopathy (HCM), in order to provide auxiliary differential diagnostic information.Methods:A retrospective study was conducted on 15 Danon disease patients (Danon disease group) who completed CMR examination, and 15 HCM patients (HCM group) and 15 healthy volunteers (control group) who were matched by gender and age were compared. TSM (pectoralis major, pectoralis minor, erector spinae, and subscapularis) area index (TSMAi), T1 relaxation time of four groups, and extracellular volume (ECV) of skeletal muscles of two groups (pectoralis major and subscapularis) were measured for all subjects. Single factor analysis of variance and KruskalWallis test were used to compare three sets of values.Results:The total TSMAi of the Danon disease group was lower than that of the HCM group and the control group [(15.37±3.28)cm 2/m 2 vs (23.02±3.88)cm 2/m 2 vs (22.33±4.67)cm 2/m 2, P<0.001], and the TSMAi of each TSM was also lower than that of the HCM group and the control group (all P<0.05). There was no statistically significant difference in TSMAi between the HCM group and the control group (all P>0.05). The native T1 values of the pectoralis major muscle in the Danon disease group and HCM group were higher than those in the control group (all P<0.05). The ECV of the pectoralis major muscle and subscapularis muscle in the Danon disease group were higher than those in the HCM group and control group, and the enhanced T1 values were lower than those in the HCM group and control group (all P<0.05); There was no statistically significant difference in ECV and the enhanced T1 values between the HCM group and the control group ( P>0.05). Conclusions:The application of CMR can effectively evaluate the changes in TSM morphology and tissue characteristics in Danon disease patients. Compared with HCM patients, Danon disease patients showed significant atrophy of TSM with increased extracellular volume. CMR provides a quantitative reference for TSM in the differential diagnosis of the two.

Exploring the hemodynamic changes of the ascending aorta before and after interventricular septal myocardial resection in obstructive hypertrophic cardiomyopathy by CMR 4D Flow technology / 中国医师杂志

Objective:To investigate the hemodynamic changes in the ascending aorta (AAo) before and after interventricular septal myocardial resection in obstructive hypertrophic cardiomyopathy (HOCM) using cardiac magnetic resonance four-dimensional blood flow (CMR 4D Flow) technology.Methods:HOCM patients who underwent interventricular septal myocardial resection at Guangdong Provincial People′s Hospital from May 2021 to September 2022 were prospectively included. Age and gender matched healthy volunteers (control group) were included during the same period. Both the control group and HOCM patients underwent CMR examination (including cine sequence and 4D Flow sequence) before and 6 months after surgery. CMR 4D flow technology was used to evaluate changes in AAo preoperative and postoperative blood flow patterns (eddy currents, spiral flow), maximum energy loss (EL max), and average energy loss (EL avg). HOCM patients underwent laboratory tests, including N-terminal pro-brain natriuretic peptide (N-pro BNP) and high-sensitivity troponin T (hsTnT). At the same time, the correlation between postoperative energy loss in HOCM patients and the degree of improvement in laboratory biomarkers was explored. Results:A total of 15 HOCM patients and 15 healthy volunteers were included. (1) In terms of blood flow patterns, the preoperative spiral flow degree of HOCM patients was significantly higher than that of the control group ( P=0.001), but the postoperative difference was not statistically significant ( P=0.059). The degree of eddy currents in HOCM patients before and after surgery was higher than that in the control group (all P<0.05). (2) In terms of energy loss, the preoperative EL max [21.17(14.30-28.10)mW vs 10.17(7.66-13.07)mW, P<0.001] and EL avg [4.87(3.46-5.77)mW vs 2.27(2.19-2.27)mW, P=0.023] of HOCM patients were higher than those of the control group, but there was no statistically significant difference between the postoperative and control groups (all P>0.05). Compared with preoperative, the postoperative EL max [12.33(8.70-17.41)mW] and EL avg [3.10(2.25-4.40)mW] of AAo in HOCM patients were significantly reduced (mean P=0.001). (3) Correlation analysis showed that there was a positive correlation ( r=0.587, P=0.021) between the EL max of AAo and the degree of improvement in hsTNT after interventricular septum myocardial resection, but no significant correlation ( r=0.229, P=0.413) with the degree of improvement in NT-pro BNP. Conclusions:The degree of postoperative AAo blood flow disorder in HOCM patients is reduced, and EL max and EL avg are significantly reduced. The EL max of postoperative AAo is positively correlated with the degree of improvement in hsTNT, suggesting that EL max may be applicable for prognostic evaluation of patients.

T1 mapping technique for evaluating myocardial gadolinium deposition in patients with apical hypertrophic cardiomyopathy / 中国医学影像技术

Objective To observe the feasibility of T1 mapping technique for evaluating myocardial gadolinium deposition in patients with apical hypertrophic cardiomyopathy(AHCM).Methods Data of 60 AHCM patients were retrospectively analyzed.The patients were divided into enhanced group and control group according to underwent gadolinium-based contrast agent(GBCA)enhanced examination or not(each n=30).Myocardial T1 value at the basal,middle and apical myocardium of the left ventricle as well as spleen T1 at the same layers were measured.T1 relative-value(T1R)was calculated and then compared between groups and among different parts of left ventricle in enhanced group.T1R in enhanced group were further analyzed based on gender,age,body mass index,cardiac function,hypertension,hyperlipidemia,diabetes,apical thickness,ejection fraction,delayed enhancement and interval time from the first enhanced examination to the last review and total dose of GBCA.Results No significant difference of T1Rbasal,T1Rmiddle nor T1Rapical was found between groups(t=0.329,1.484,0.720,all P＞0.05),nor of T1R in different parts of left ventricle within enhanced group(F=0.765,P＞0.05).In enhanced group,significant differences of myocardial T1R was found between different genders as well as patients with or without hypertension(both P＜0.05).Conclusion T1 mapping technology could be used for evaluating myocardial gadolinium deposition in patients with AHCM.

Trabecular Characteristics of Hypertrophic Cardiomyopathy Based on Cardiac Magnetic Resonance Fractal Analysis:A Preliminary Study / 中国医学影像学杂志

Purpose To evaluate the feasibility of cardiac magnetic resonance fractal analysis in evaluating left ventricular trabecular complexity in hypertrophic cardiomyopathy(HCM),and to study the degree of left ventricular trabecular complexity in HCM and the relationship between excessive trabecular complexity and cardiac function.Materials and Methods From August 2020 to December 2022,a total of 80 patients with HCM from the Second Affiliated Hospital of Nanchang University were retrospectively analyzed.Additionally,80 healthy volunteers were recruited as the control group.Left ventricular functional parameters and fractal dimension(FD)of left ventricular trabecular myocardium were measured.The differences of mean global FD,max basal FD and max apical FD were compared between the HCM group and the control group,the correlation between FDs and cardiac function parameters was evaluated.The diagnostic efficiency of mean global FD,max apical FD and max basal FD was analyzed via receiver operating characteristic curve.Results The mean global FD of HCM group was significantly higher than that of normal group,and the difference was statistically significant(1.303±0.047 vs.1.229±0.026;t=-12.387,P<0.001).Mean global FD showed the best performance in differentiating HCM from normal control group.The optimal cut-off value for the diagnosis of HCM was 1.251,with the area under curve of 0.933(95%CI 0.896-0.969).Mean global FD was positively correlated with maximum wall thickness and left ventricular mass index(r=0.686,0.687,P<0.001),and max apical FD was positively correlated with left ventricular ejection fraction(r=0.520,P<0.001).Conclusion The FD obtained by cardiac magnetic resonance fractal analysis technique is reproducible and has definite value in the diagnosis of HCM,with association with the structure and function of left heart.

Comparison of Early and Mid-Term Outcomes After Classic and Modified Morrow Septal Myectomy in Patients with Hypertrophic Obstructive Cardiomyopathy

ABSTRACT Introduction: The aim of our study is to compare the early and mid-term outcomes of patients with hypertrophic obstructive cardiomyopathy who underwent classic and modified Morrow septal myectomy. Methods: Between 2014 and 2019, 48 patients (24 males; mean age 49.27±16.41 years) who underwent septal myectomy were evaluated. The patients were divided into two groups - those who underwent classic septal myectomy (n=28) and those who underwent modified septal myectomy (n=20). Results: Mitral valve intervention was higher in the classic Morrow group than in the modified Morrow group, but there was no significant difference (P=0.42). Mortality was found to be lower in the modified Morrow group than in the classic Morrow group (P=0.01). In both groups, the mean immediate postoperative gradient was significantly higher than the mean of the 3rd and 12th postoperative months. The preoperative and postoperative gradient difference of the modified Morrow group was significantly higher than of the classic Morrow group (P<0.001). Conclusion: Classic Morrow and modified Morrow procedures are effective methods for reducing left ventricular outflow tract obstruction. The modified Morrow procedure was found to be superior to the classic Morrow procedure in terms of reducing the incidence of mitral valve intervention with the reduction of the left ventricular outflow tract gradient.

Cuando la genética estaba oculta: miocardiopatía hipertrófica por variante MYBPC3 c. 1102A>T (p.Lys368*) refractaria a manejo médico: reporte de un caso / When genetics were hidden: hypertrophic cardiomyopathy due to MYBPC3 c. 1102A>T (p.Lys368*) variant refractory to medical management: case report / Quando a genética estava oculta: cardiomiopatia hipertrófica por variante MYBPC3 c. 1102A>T (p.Lys368*) refractária à manejo médico: reporte de um caso

La miocardiopatía hipertrófica es cada vez más diagnosticada. Es una condición genética que genera hipertrofia miocárdica, fibrosis, isquemia y apoptosis con obstrucción del tracto de salida del ventrículo izquierdo. Puede generar síncope, falla cardíaca y muerte súbita. El tratamiento es farmacológico y se requiere cirugía si hay refractariedad. Se presenta un caso de miocardiopatía hipertrófica asociada a variante genética patogénica en un paciente no respondedor a manejo médico óptimo. La importancia de este artículo radica en lo determinante que es la genética para el abordaje diagnóstico y el establecimiento del origen y pronóstico de esta enfermedad.

Hypertrophic cardiomyopathy is increasingly diagnosed. It is a genetic condition that leads to myocardial hypertrophy, fibrosis, ischemia, and apoptosis with obstruction of the left ventricular outflow tract. It can result in syncope, heart failure, and sudden death. Treatment is pharmacological, and surgery is required in cases of refractoriness. A case of hypertrophic cardiomyopathy associated with a pathogenic genetic variant is presented in a patient unresponsive to optimal medical management. The importance of this article lies in how crucial genetics is for the proper diagnostic approach and the establishment of the origin and prognosis of this disease.

A miocardiopatia hipertrófica está sendo diagnosticada cada vez mais. É uma condição genética que leva à hipertrofia miocárdica, fibrose, isquemia e apoptose com obstrução do trato de saída do ventrículo esquerdo. Pode resultar em síncope, insuficiência cardíaca e morte súbita. O tratamento é farmacológico e a cirurgia é necessária em casos de refratariedade. Apresenta-se um caso de miocardiopatia hipertrófica associada a uma variante genética patogênica em um paciente não responsivo ao manejo médico ótimo. A importância deste artigo reside na determinante genética para a abordagem diagnóstica adequada e para o estabelecimento da origem e prognóstico desta doença.

Estudio preliminar de correlación fenotipo-genotipo en miocardiopatías de pacientes derivados a un centro de alta complejidad del conurbano bonaerense / A Preliminary Study of the Phenotype-Genotype Correlation in Cardiomyopathies in Patients Referred to a Tertiary Healthcare Center in the Suburbs of Buenos Aires

RESUMEN Introducción : Las miocardiopatías se definen como un trastorno del miocardio en el que el músculo cardíaco es estructural y funcionalmente anormal, en ausencia de enfermedad arterial coronaria, hipertensión arterial (HTA), enfermedad valvular y enfermedad cardíaca congénita. Estas enfermedades son relativamente frecuentes, y suponen una importante causa de morbimortalidad a nivel global. Aunque el estudio genético se recomienda para el cribado familiar, la falta de datos robustos sobre asociaciones genotipo-fenotipo específicas ha reducido su impacto en el manejo clínico. Objetivos : El objetivo de este estudio es analizar la frecuencia de mutaciones en una población de pacientes con miocardiopatía derivados a un centro de alta complejidad y el análisis de la correlación genotipo-fenotipo en las mutaciones identificadas. Material y métodos: Se estudiaron en forma prospectiva 102 pacientes con sospecha de miocardiopatía hipertrófica (MCH) familiar, de los cuales 70 constituían casos índices, de una cohorte ambispectiva de pacientes con miocardiopatías controladas en un hos pital público de alta complejidad de tercer nivel de atención de la provincia de Buenos Aires, desde enero 2012 al 30 agosto 2022. Resultados : De 102 pacientes 83 fueron considerados afectados. De eelos, 31 eran MCH y 52 fenocopias, sin diferencia en el pronóstico. Se realizó estudio genético en 77 pacientes, de los cuales 57 presentaron mutaciones reconocibles, en el 80% de los casos coincidentes con un Score de Mayo ≥3. Se detectaron 28 variantes de significado incierto. Conclusiones : Se comprobó que realizar estudio molecular guiado por el Score de Mayo permitió obtener un alto grado de probabilidad de detectar mutaciones. Se evidenció la importancia del estudio molecular debido a la existencia de solapamiento fenotípico y genotípico de las miocardiopatías. El conocimiento de la variante genética causal actualmente no afecta el manejo clínico de la mayoría de los pacientes con MCH, pero es de ayuda ante un pequeño grupo de genes que tienen opciones de tratamiento.

ABSTRACT Background : Cardiomyopathies are defined as a disorder of the myocardium in which the heart muscle is structurally and functionally abnormal, in the absence of coronary artery disease, hypertension (HT), valvular heart disease and congenital heart disease. These diseases are relatively common and a major cause of morbidity and mortality worldwide. Although genetic testing is recommended for family screening, lack of solid data on specific genotype-phenotype associations has reduced its impact on clinical management. Objectives : This study aims to analyze the frequency of mutations in a population of patients with cardiomyopathy referred to a tertiary healthcare center and to analyze the genotype-phenotype correlation of the identified mutations. Methods : We prospectively included 102 patients with suspected familial hypertrophic cardiomyopathy (HCM), 70 of which were index cases, from an ambispective cohort of patients with cardiomyopathies treated in a tertiary healthcare public hos pital in the province of Buenos Aires, from January 2012 to August 30, 2022. Results : Of 102 patients, 83 were considered affected. Of these, 31 were HCM and 52 were phenocopies, with no difference in prognosis. A genetic study was carried out in 77 patients, of whom 57 presented recognizable mutations, in 80% of the cases coinciding with a Mayo Score ≥3. Twenty-eight variants of uncertain significance were detected. Conclusions : It was confirmed that molecular testing guided by the Mayo Score provided high probability of detecting mutations. Molecular testing proved to be important due to the phenotypic and genotypic overlap in cardiomyopathies. Understanding the causative genetic variant, nowadays, does not affect the clinical management of most HCM patients, but is helpful in a small group of genes with treatment options.

Adenosine stress myocardial contrast echocardiography evaluates myocardial perfusion abnormalities in patients with hypertrophic cardiomyopathy / 中华超声影像学杂志

Objective:To detect the abnormal changes of myocardial blood perfusion in patients with hypertrophic cardiomyopathy(HCM) by myocardial contrast echocardiography (MCE) combined with adenosine stress test.Methods:Fifteen adult patients with HCM who were treated in Fuwai Central China Cardiovascular Hospital from May 2021 to March 2022 were prospectively selected as the HCM group, and eighteen healthy volunteers matched by gender, age and body surface area during the same period were chosen as the control group. All subjects underwent routine echocardiography, rest and adenosine stress MCE. The MCE images were analyzed by QLab software to obtain the myocardial perfusion parameters: peak signal intensity (A value), rising slope of the curve (β value) and A×β value, and the differences of above parameters between the two groups were compared.According to whether the end-diastolic wall thickness ≥12 mm, the myocardial segments in the HCM group were divided into hypertrophic segments and non-hypertrophic segments. The differences in myocardial perfusion parameters were compared among control group segments, hypertrophic segments and non-hypertrophic segments of the HCM group. The correlations of stress myocardial blood flow with maximal left ventricular wall thickness (MLVWT), left ventricular mass index (LVMI) and left atrial volume index (LAVI) in the HCM group were analyzed.Results:Compared with the control group, the A value, β value and A×β value of whole myocardium, hypertrophic segments and non-hypertrophic segments in the HCM group were significantly decreased in the rest and adenosine stress state, and the differences were statistically significant (all P<0.05). In the stress state, the A value, β value and A×β value of the hypertrophic segments were significantly lower than those in the non-hypertrophic segments in the HCM group, and the detection rate of abnormal perfusion segments in the HCM group was significantly higher than that in the rest state(all P<0.05). Compared with the control group, the myocardial blood flow reserve of whole myocardium, hypertrophic segments and non-hypertrophic segments in the HCM group were significantly decreased, and the differences were statistically significant(all P<0.05). The stress myocardial blood flow in the HCM group was negatively correlated with MLVWT, LVMI and LAVI ( r=-0.815, -0.805, -0.742; all P<0.05). Conclusions:Myocardial blood perfusion abnormalities can occur in both hypertrophic and non-hypertrophic myocardial segments in patients with HCM, and adenosine stress MCE can significantly improve the sensitivity of detecting myocardial perfusion abnormalities. The stress myocardial blood flow in patients with HCM is negatively correlated with MLVWT, LVMI and LAVI.

A follow-up study of percutaneous intramyocardial septal radiofrequency ablation in the treatment of obstructive hypertrophic cardiomyopathy with mild septal hypertrophy / 中华超声影像学杂志

Objective:To evaluate the clinical efficacy of percutaneous intramyocardial septal radiofrequency ablation (PIMSRA) in the treatment of obstructive hypertrophic cardiomyopathy (HOCM) with mild septal hypertrophy.Methods:Forty-five HOCM patients with mild septal hypertrophy (the maximal left ventricular wall thickness is 15-19 mm) who were treated with PIMSRA between November 2016 to February 2021 in the Hypertrophic Cardiomyopathy Center of Xijing Hospital of Air Force Military Medical University were enrolled, and their clinical datas were collected and analyzed. The clinical symptoms and NYHA functional class before operation, 6 months and 1 year after operation were collected. Interventricular septum thickness, left ventricular outflow tract pressure gradient, left ventricular outflow tract diameter, mitral regurgitation, left ventricular systolic and diastolic function were evaluated by transthoracic echocardiography before operation, 6 months and 1 year after operation, intraoperative complications were monitored and recorded. Postoperative arrhythmias were monitored by routine 12 lead ECG and 24-hour ambulatory ECG.Results:All patients successfully completed PIMSRA procedure.No clinical adverse events such as death, bleeding and stroke occurred during and around the operation.No left bundle branch block, complete atrioventricular block and malignant arrhythmia occurred after the operation. All patients did not need permanent pacemaker implantation.NYHA functional class and clinical symptoms of patients were significantly improved after 6 months compared with values before operation (all P<0.001, respectively), it remained stable for 1 year after operation; Anterior interventricular septum, posterior interventricular septum, maximal left ventricular wall thickness all significantly decreased (all P<0.001, respectively), left ventricular outflow tract diameter widened ( P<0.001), continuous improvement 1 year after operation; left ventricular outflow tract gradient and provoked left ventricular outflow tract gradient all significantly decreased, mitral regurgitation decreased and SAM classification reduced after 6 months compared with values before operation (all P<0.001, respectively); left ventricular end-diastolic diameter widened and left atrial diameter decreased (all P<0.001, respectively), it remained stable for 1 year after operation. Left atrial volume index decreased ( P<0.001), with continuous improvement 1 year after operation; The ratio of early diastolic mitral valve velocity to early diastolic mitral annulus velocity (E/e′) decreased ( P=0.001), it remained stable for 1 year after operation. There were no significant differences in left ventricular end diastolic volume, left ventricular end systolic volume and left ventricular ejection fraction among the three groups (all P>0.05). Conclusions:PIMSRA is effective in the treatment of obstructive hypertrophic cardiomyopathy with mild ventricular septal hypertrophy.

Effect of echocardiography-guided percutaneous intramyocardial septal radiofrequency ablation on the Lown classification in patients with hypertrophic obstructive cardiomyopathy / 中华超声影像学杂志

Objective:To investigate the effect of percutaneous intramyocardial septal radiofrequency ablation (PIMSRA) guided by echocardiography on the Lown classification of ventricular arrhythmias in patients with hypertrophic obstructive cardiomyopathy (HOCM).Methods:A total of 85 patients with HOCM who received PIMSRA treatment at Xijing Hospital of Air Force Military Medical University from May 2017 to October 2019 were retrospectively selected. All patients underwent 24-hour Holter examinations before and 1 year after PIMSRA to obtain parameters related to Lown classification. The changes in Lown grades after PIMSRA were analyzed. The patients were divided into improved group and unimproved group according to whether there was significant improvement in Lowen′s grades, and the difference of the parameters related were compared. The influencing factors of the changes in Lown classification were analyzed.Results:Compared with before PIMSRA, there was a significant improvement in the Lown classification after PIMSRA ( P=0.001). The patients with Lown grade Ⅰ increased significantly ( P=0.001), and the patients with grade Ⅲ decreased significantly ( P=0.005). There were no significant changes in patients with Lown grades 0, Ⅱ, and Ⅳ (all P>0.05). The proportion of patients with family history of hypertrophic cardiomyopathy (HCM), the baseline Lown classes, the reduction rate of the maximum left ventricular wall thickness and the reduction rate of the provocative left ventricular outflow tract gradient (LVOTG) were higher in the improved group than the unimproved group (all P<0.05). Multivariate Logistic regression results showed that HCM family history ( OR=3.95, 95% CI=1.34-11.64, P=0.013), baseline Lown classes ( OR=2.01, 95% CI=1.25-3.22, P=0.004) and the reduction rate of the provocative LVOTG gradient ( OR=1.02, 95% CI=1.00-1.04, P=0.041) were independent factors of postoperative Lown classification improvement. Conclusions:The Lown classes of HOCM patients after PIMSRA is significantly improved.HCM family history, the baseline Lown classes, and the reduction rate of postoperative provocative LVOTG are independent influencing factors for the improvement of Lown grade.

Study of left ventricular myocardial mechanics in patients with different risk stratifications of hypertrophic cardiomyopathy by four-dimensional automatic left ventricular quantitation technology / 中华超声影像学杂志

Objective:To explore the application value of four-dimensional automatic left ventricular quantitation(4D Auto LVQ) technology, in evaluating the myocardial mechanics in patients with different risk stratifications of hypertrophic cardiomyopathy(HCM).Methods:A total of 88 HCM patients and 20 healthy volunteers were selected from February 2020 to February 2022 in the First Affiliated Hospital of Zhengzhou University. According to the HCM Risk-SCD score, HCM patients were divided into 3 groups: low-risk group( n=49), intermediate-risk group( n=21), and high-risk group( n=18). Conventional ultrasound parameters were collected, and 4D Auto LVQ technology was used to obtain the mechanical parameters of left ventricular myocardium, including global longitudinal strain(GLS) , global circumferential strain(GCS), global area strain(GAS), global radial strain(GRS), twist and torsion. The differences in these parameters among the four groups were compared. The predictive values of conventional ultrasound parameters and myocardial mechanical parameters in patients with intermediate- and high-risk HCM patients were analyzed by ROC curve. Results:①Left ventricular end-diastolic diameter, left ventricular end-diastolic volume, left ventricular end-systolic volume, and peak systolic velocity of mitral annulus in the low-, intermediate-, and high-risk groups were lower than those in the control group while left ventricular maximal wall thickness(LVMWT) and early diastolic peak velocity of mitral value orifice/early diastolic peak velocity of mitral annulus(E/e′) were higher, left atrial diameter(LAD) and left ventricular outflow tract gradients(LVOTG) in the intermediate- and high-risk groups were higher than the low-risk group(all P<0.05). ②Compared with the control group, the GLS of HCM patients was lower, and the GLS of the intermediate- and high-risk groups was lower than the low-risk group. GCS and GRS in the intermediate- and high-risk groups were lower than those in the low-risk group. GAS in the high-risk group was lower than the low-risk and the control group, but higher than the intermediate-risk group(all P<0.05). Compared with the control group, the twist and torsion in the intermediate- and high-risk groups were higher, but lower than the low-risk group, and the differences were statistically significant(all P<0.05). ③The ROC results showed that the area under the curve(AUC) of the model containing conventional ultrasound parameters(LVWMT, LAD, and LVOTG) for predicting intermediate- and high-risk HCM patients was 0.811, with a sensitivity of 0.769 and a specificity of 0.755. The AUC of the conventional ultrasound parameters combined with myocardial mechanical parameters was 0.904, as the sensitivity was 0.667 and the specificity was 0.980. Conclusions:4D Auto LVQ can evaluate the mechanical characteristics of LV myocardium in HCM patients with different risk stratifications. Myocardial mechanical parameters combined with conventional ultrasound parameters can improve the diagnostic performance of patients with intermediate- and high-risk HCM.

Study of the effect of mid-ventricular obstruction on left ventricular systolic function in patients with hypertrophic cardiomyopathy by four-dimensional automatic left ventricular quantitation technology / 中华超声影像学杂志

Objective:To investigate the effect of mid-ventricular obstruction (MVO) on left ventricular systolic function in patients with hypertrophic cardiomyopathy(HCM) by four-dimensional automatic left ventricular quantitation technology(4D Auto LVQ).Methods:Fifty-seven hypertrophic obstructive cardiomyopathy patients were selected from December 2020 to October 2022 in the First Affiliated Hospital of Zhengzhou University. According to the presence of MVO, HCM patients were divided into two groups: HCM 1 group, HCM without MVO ( n=34); HCM 2 group, HCM with MVO ( n=23). In addition, 25 healthy subjects in the same period were selected as the control group. Conventional ultrasound parameters were collected, and 4D Auto LVQ technology was used to obtain the mechanical parameters of left ventricular myocardium, including left ventricular longitudinal strain (GLS), circumferential strain (GCS), area strain (GAS), radial strain (GRS), segmental longitudinal strain (SLS) and area strain (SAS). The differences of these parameters among the three groups were compared. Results:①Compared with the control group, the thickness of the maximum basal segment of interventricular septum, the thickness of the middle segment of the maximum interventricular septum, the thickness of the apical segment of the interventricular septum, the thickness of the left ventricular posterior wall and left atrium diameter were significantly increased. Six-minute walk distance and the left ventricular end-diastolic diameter was decreased in the two groups of HCM(all P<0.05). Left ventricular outflow tract gradients in HCM 1 group was higher than HCM 2 group( P<0.05), but there was no significant difference in left ventricular ejection fraction among the three groups( P>0.05). There was significant difference in the incidence of left ventricular apical aneurysm among the three groups( P<0.05). ②Compared with the control group, the GLS in both HCM groups was lower, and it was lower in the HCM 2 group than in the HCM 1 group(all P<0.05) the GRS and GAS in both HCM groups were lower than in the control group ( P<0.05), and there was no significant difference between the two groups of HCM, and there was no significant difference in GCS among the three groups(all P>0.05). ③Compared with the control group, the SLS of basal segment, middle segment, apical cap, posterior septum, inferior wall and lateral wall in HCM group were significantly lower than those in control group. The SLS of apical segment of posterior septum, anterior septum, anterior wall, posterior wall, inferior wall and apical segment of posterior septum, lateral wall and inferior wall in HCM 2 group were significantly lower than HCM 1 group(all P<0.05), but there was no significant difference in SLS of posterior septum, anterior septum, anterior wall, lateral wall and inferior wall between the two groups(all P>0.05). ④Compared with the control group, the SAS of posterior septal basal segment, middle segment, anterior septal middle segment, anterior wall basal segment, middle segment, apical segment, lateral wall basal segment, middle segment, apical segment, posterior wall basal segment, middle segment, inferior wall basal segment, middle segment and apical cap in HCM groups were significantly lower than the control group(all P<0.05), but there was no significant difference in SAS between the two groups of HCM( P>0.05). Conclusions:4D Auto LVQ can quantitatively evaluate the damage of MVO on the left ventricular systolic function in patients with HCM, especially for the evaluation of local myocardial function damage in the medial segment and apical segment.

Early identification of familial hypertrophic cardiomyopathy mutation gene carriers by constructing Nomogram prediction model based on parametric characteristics of two-dimensional transthoracic echocardiography and three-dimensional speckle tracking imaging / 中华超声影像学杂志

Objective:To explore the characteristics of echocardiographic parameters among the many parameters of two-dimensional transthoracic echocardiography(2D-TTE) and three-dimensional speckle tracking imaging (3D-STI) that can be used for early identification of familial hypertrophic cardiomyopathy(FHCM) mutation gene carriers, and construct a Nomogram prediction model, in order to provide a diagnostic method for early identification of G+ P- patients for clinical practice.Methods:A total of 15 FHCM families admitted to the General Hospital of Ningxia Medical University from November 2017 to August 2022 were enrolled.Whole exome sequencing and Sanger sequencing technology were used for gene detection, among which 54 were G+ P- and 75 were G-P-. Stratified random sampling was used to divide the subjects into training set ( n=90) and test set ( n=39) according to the ratio of 7∶3. Philips iE33 ultrasonic diagnostic instrument and TomTec offline software were used to obtain relevant ultrasonic parameters. Lasso regression and Logistic regression were used to screen echocardiographic parameters and obtain independent risk factors for early prediction of G+ P-, based on which a Nomogram prediction model was established. Results:①Lasso-Logistic regression showed that global longitudinal strain(GLS) ( OR=1.739, 95% CI=1.305-2.316) and left ventricular outflow trac velocity time integral(LVOT-VTI) ( OR=1.358, 95% CI=1.072-1.722) could be used as independent risk factors for early prediction of G+ P-. ②The Nomogram prediction model was established based on the above indicators. After 1000 internal verifications of Bootstrap self-sampling, the C-indices of the training set and the test set were 0.885 (95% CI=0.816-0.954), 0.878 (95% CI=0.764-0.992), which had good internal consistency. ③The results of the calibration curve showed that the risk of G+ P- predicted by the Nomogram model was basically consistent with the actual risk (training set P=0.990, test set P=0.961); the clinical decision curve shows that under different threshold probabilities, using this prediction model to provide patients with clinical decision-making could bring benefits to patients. Conclusions:Echocardiographic parameters GLS and LVOT-VTI can be used as independent risk factors to predict FHCM mutation gene carriers. The Nomogram prediction model has good discrimination, goodness of fit and clinical benefit in identifying whether the family members of FHCM patients carry the mutation gene, and it can provide a new idea and evaluation method for the early identification of FHCM mutation gene carriers by echocardiography.

The value of radiomics features derived from cardiac MR cine images in predicting late gadolinium enhancement in patients with hypertrophic cardiomyopathy / 中华放射学杂志

Objective:To investigate the value of radiomics features derived from cardiac MR (CMR) cine images for predicting late gadolinium enhancement (LGE) in patients with hypertrophic cardiomyopathy (HCM).Methods:Firstly, a total of 300 HCM patients with definite diagnosis who underwent CMR examination in Beijing Anzhen Hospital from May 2017 to August 2021 were retrospectively included, and were divided into a training set and a test set with a proportion of 7∶3 using random stratified sampling method. Then, a total of 89 HCM patients with definite diagnosis who underwent CMR examination in Beijing Anzhen Hospital from January 2022 to May 2023 were included for external validation. The CVI42 software was used to obtain the cardiac function parameters. Intraclass correlation coefficient (ICC), Pearson correlation coefficient and least absolute shrinkage and selection operator (LASSO) were used to select radiomics features. Finally, LASSO regression and three machine learning algorithms (including support vector machine, linear discriminant analysis and naive Bayes) were used to build prediction models. The area under the receiver operating characteristic curve (AUC) was used to evaluate the prediction value of the model.Results:Totally 1 409 features were extracted from each patient, and 19 features were retained to build radiomics signature after dimension reduction. Although no significant differences among the four methods, the prediction performance and stability of LASSO regression were relatively good. The AUC was 0.795 (95%CI 0.735-0.855) in the training set, 0.765 (95%CI 0.668-0.862) in the test set and 0.721(95%CI 0.598-0.845) in the external validation set.Conclusions:The features extracted from CMR cine images can be used to predict LGE in HCM patients. LASSO regression is recommended for model construction.

Comparison of sternotomy and thoracoscopic extended myectomy in the treatment of elderly patients with hypertrophic obstructive cardiomyopathy / 中华老年医学杂志

Objective:To evaluate the clinical effectiveness of thoracoscopic extended septal myectomy in elderly patients diagnosed with hypertrophic obstructive cardiomyopathy(HOCA).Methods:From April 2019 to August 2021, 36 elderly patients with HOCM who underwent septal myectomy were retrospectively analyzed, including 20 patients under thoracoscopy and 16 patients under median sternotomy.The surgical outcomes, echocardiography and follow-up results were compared between the two groups.Results:The number of intracardiac incisions in the Thoracoscopy group was significantly lower than that in the median thoracotomy group( P=0.001).Additionally, the ventilation time of ≤24 hours was higher in the thoracoscopy group compared to the median thoracotomy group(75.0% vs 31.2%, P=0.017).It is noteworthy that there were no deaths in the thoracoscopic group.However, one patient experienced left ventricular rupture during mitral valve replacement and had to be converted to median sternotomy.This patient also developed low cardiac output syndrome after the operation but was discharged smoothly.In the median sternotomy group, one patient died in the hospital, two patients developed low cardiac output syndrome, and one patient underwent re-sternotomy due to bleeding.Importantly, neither group experienced ventricular septal perforation or complete atrioventricular block.The number of intracardiac incisions in the thoracoscopy postoperative interventricular septal thickness was significantly reduced in both groups.In the thoracoscopic group, the interventricular septal thickness was(19.2±3.5)mm and(11.3±2.2)mm, with a t-value of 8.531 and a p-value of <0.001.In the median sternotomy group, the interventricular septal thickness was(19.9±3.9)mm and(13.1±2.6)mm, with a t-value of 5.664 and a p-value of <0.001.This reduction effectively relieved left ventricular outflow tract obstruction.In the thoracoscopic group, the left ventricular outflow tract obstruction decreased from(96.2±32.9)mmHg to(8.2±3.4)mmHg, with a t-value of 11.894 and a p-value of <0.001.In the median sternotomy group, the left ventricular outflow tract obstruction decreased from(83.2±40.9)mmHg to(13.3±19.3)mmHg, with a t-value of 5.997 and a p-value of <0.001.The patients in the thoracoscopic group were followed up for an average of(13.5±8.8)months, and no complications occurred.The patients in the median sternotomy group were followed up for an average of(15.8±9.4)months.One patient in this group underwent alcohol septal ablation for residual obstruction and developed complete atrioventricular block. Conclusions:Thoracoscopic extended myectomy in elderly patients with(HOCM)can achieve comparable therapeutic effectiveness and safety compared to the median sternotomy approach.This minimally invasive procedure is associated with shorter ventilation time and can also minimize the need for additional intracardiac incisions, especially when simultaneous mitral valve treatment is necessary.

Clinical application progress of radiofrequency ablation in the treatment of hypertrophic obstructive cardiomyopathy / 中国医师杂志

Hypertrophic obstructive cardiomyopathy (HOCM) is the most common type of hypertrophic cardiomyopathy, which is prone to left ventricular outflow obstruction and causes various adverse effects. It is also the main cause of sudden death in adolescents and athletes. Timely intervention is crucial for the prognosis of patients. Radiofrequency ablation has been widely used in the treatment of various arrhythmias, but it is still a new treatment method in HOCM. This article mainly reviews the clinical application progress of radiofrequency ablation in the treatment of HOCM patients.

Application progress of non-vitamin K antagonist oral anticoagulants in hypertrophic cardiomyopathy with atrial fibrillation / 中国医师杂志

Atrial fibrillation (AF) is the most common supraventricular arrhythmia in patients with hypertrophic cardiomyopathy. Patients with hypertrophic cardiomyopathy and atrial fibrillation have a significantly increased risk of thromboembolism. Currently, guidelines recommend lifelong anticoagulant therapy for all such patients. The data on the use of non-vitamin K antagonist oral anticoagulants in patients with hypertrophic cardiomyopathy and atrial fibrillation are limited, and their efficacy and safety are not well established. This article provides a review of the current evidence on this issue.

Avaliação Prognóstica da Microalternância da onda T na Cardiomiopatia Hipertrófica em um Seguimento Clínico de 9 anos / Prognostic Evaluation of Microvolt T-Wave Alternans in Hypertrophic Cardiomyopathy: 9-year Clinical Follow-up

Resumo Fundamento: A morte súbita cardíaca (MSC), decorrente de arritmias ventriculares, é a principal complicação da cardiomiopatia hipertrófica (CMH). A microalternância da onda T (MAOT) está associada à ocorrência de arritmias ventriculares em diversas cardiopatias, mas seu papel na CMH permanece incerto. Objetivo: Avaliar associação da MAOT com a ocorrência de MSC ou arritmias ventriculares malignas em pacientes com CMH. Método: Pacientes com diagnóstico de CMH e classe funcional I-II (NYHA) foram selecionados de forma consecutiva. No início do seguimento os participantes realizaram a avaliação da MAOT pela metodologia da média móvel modificada no teste de esforço. Os resultados foram classificados em alterado ou normal. O desfecho foi composto por MSC, fibrilação ventricular, taquicardia ventricular sustentada (TVS) e terapia apropriada do cardioversor desfibrilador implantável (CDI). O nível de significância estatística foi de 5%. Resultados: Um total de 132 pacientes (idade média de 39,5±12,6 anos) foram incluídos, com tempo de seguimento médio de 9,5 anos. A MAOT foi alterada em 74 (56%) participantes e normal em 58 (44%). Durante o seguimento, nove (6,8%) desfechos ocorreram, com prevalência de 1,0%/ano, sendo seis casos de MSC, dois choques apropriados do CDI e um episódio de TVS. MAOT alterada foi associada à taquicardia ventricular não sustentada no Holter (p=0,016), espessura septal≥30 mm (p<0,001) e resposta inadequada da pressão arterial ao esforço (p=0,046). Cinco pacientes (7%) e quatro pacientes (7%) com MAOT alterada e normal, respectivamente, apresentaram desfecho primário [OR=0,85(IC95%: 0,21-3,35, p=0,83)]. Curvas de eventos de Kaplan-Meir não apresentaram diferenças entre MAOT normal e alterada. Conclusão: A MAOT alterada não foi associada à ocorrência de MSC ou arritmias ventriculares potencialmente fatais em pacientes com CMH, e a baixa taxa desses eventos em um seguimento em longo prazo sugere o bom prognóstico dessa cardiopatia.

Abstract Background: Sudden cardiac death (SCD) resulting from ventricular arrhythmia is the main complication of hypertrophic cardiomyopathy (HCM). Microvolt T-wave alternans (MTWA) is associated with the occurrence of ventricular arrhythmias in several heart diseases, but its role in HCM remains uncertain. Objective: To evaluate the association of MTWA with the occurrence of SCD or potentially fatal ventricular arrhythmias in HCM patients in a long-term follow-up. Methods: Patients diagnosed with HCM and NYHA functional class I-II were consecutively selected. At the beginning of the follow-up, the participants performed the MTWA evaluation using the modified moving average during the stress test. The results were classified as altered or normal. The composite endpoint of SCD, ventricular fibrillation, sustained ventricular tachycardia (SVT) or appropriate implantable cardiac defibrillation (ICD) therapy was assessed. The level of significance was set at 5%. Results: A total of 132 patients (mean age of 39.5 ± 12.6 years) were recruited and followed for a mean of 9.5 years. The MTWA test was altered in 74 (56%) participants and normal in 58 (44%). Nine events (6.8%) occurred during the follow-up, with a prevalence of 1.0%/year - six SCDs, two appropriate ICD shocks and one episode of (SVT). Altered MTWA was associated with non-sustained ventricular tachycardia on Holter (p = 0.016), septal thickness ≥30 mm (p < 0.001) and inadequate blood pressure response to effort (p = 0.046). Five patients with altered MTWA (7%) and four patients with normal MTWA (7%) had the primary outcome [OR = 0.85 (95% CI: 0.21 - 3.35, p=0.83)]. Kaplan-Meir event curves showed no differences between normal and altered MTWA. Conclusion: Altered MTWA was not associated with the occurrence of SCD or potentially fatal ventricular arrhythmias in HCM patients, and the low rate of these events during long-term follow-up suggests the good prognosis of this heart disease.