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.

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.

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.

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.

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.

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.

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.

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.

Acometimento do Ventrículo Direito na Cardiomiopatia por Depósito de Glicogênio (PRKAG2): Análise Ecocardiográfica Convencional e Avançada / Right Ventricle Involvement by Glycogen Storage Cardiomyopathy (PRKAG2): Standard and Advanced Echocardiography Analyses

Resumo Fundamento A síndrome do PRKAG2 é uma doença hereditária autossômica dominante rara, de início precoce. Objetivamos descrever os achados ecocardiográficos do ventrículo direito (VD) usando modalidades bi e tridimensionais (2D e 3D), incluindo índices de deformação miocárdica nesta cardiomiopatia. Também objetivamos demonstrar se esta técnica poderia identificar alterações na função do VD que pudessem distinguir quaisquer achados particulares. Métodos Trinta pacientes com síndrome do PRKAG2 (R302Q e H401Q) geneticamente comprovada, 16 (53,3%) do sexo masculino, com idade média de 39,1 ± 15,4 anos, foram submetidos a exame ecocardiográfico completo. A visão de 4 câmaras com foco no VD foi adquirida para medições 2D e 3D. Os testes t de Student ou Wilcoxon-Mann-Whitney foram usados para comparar as variáveis numéricas entre 2 grupos, e p < 0,05 foi considerado significativo. Resultados Doze pacientes (40%) tiveram marca-passo implantado por 12,4 ± 9,9 anos. A espessura diastólica média da parede livre do VD foi de 7,9 ± 2,9 mm. O strain longitudinal de 4 câmaras do VD (SL4VD), incluindo a parede livre e o septo interventricular, foi de -17,3% ± 6,7%, e o strain longitudinal da parede livre do VD (SLPLVD) foi de −19,1% ± 8,5%. A razão apical do SLPLVD mediu 0,63 ± 0,15. A fração de ejeção (FE) 3D média do VD foi de 42,6% ± 10,9% e abaixo dos limites normais em 56,7% dos pacientes. Correlação positiva ocorreu entre FE 3D do VD, SL4VD e SLPLVD, principalmente para pacientes sem marca-passo (p = 0,006). Conclusão O envolvimento do VD em PRKAG2 é frequente e ocorre em diferentes graus. A ecocardiografia é uma ferramenta valiosa na detecção de anormalidades miocárdicas do VD nesta condição. O uso de SL4VD 2D, SLPLVD e FE 3D oferecem indicadores confiáveis de disfunção sistólica do VD nesta cardiomiopatia rara e desafiadora.

Abstract Background PRKAG2 syndrome is a rare, early-onset autosomal dominant inherited disease. We aimed to describe the right ventricle (RV) echocardiographic findings using two and three-dimensional (2D and 3D) modalities including myocardial deformation indices in this cardiomyopathy. We also aimed to demonstrate whether this technique could identify changes in RV function that could distinguish any particular findings. Methods Thirty patients with genetically proven PRKAG2 (R302Q and H401Q), 16 (53.3%) males, mean age 39.1 ± 15.4 years, underwent complete echocardiography examination. RV-focused, 4-chamber view was acquired for 2D and 3D measurements. Student's t or Wilcoxon-Mann-Whitney tests were used to compare numerical variables between 2 groups, and p < 0.05 was considered significant. Results Twelve patients (40%) had a pacemaker implanted for 12.4 ± 9.9 years. RV free wall mean diastolic thickness was 7.9 ± 2.9 mm. RV 4-chamber longitudinal strain (RV4LS), including the free wall and interventricular septum, was -17.3% ± 6.7%, and RV free wall longitudinal strain (RVFWLS) was −19.1% ± 8.5%. The RVFWLS apical ratio measured 0.63 ± 0.15. Mean RV 3D ejection fraction (EF) was 42.6% ± 10.9% and below normal limits in 56.7% of patients. Positive correlation occurred between RV 3DEF, RV4LS, and RVFWLS, especially for patients without a pacemaker (p = 0.006). Conclusion RV involvement in PRKAG2 syndrome is frequent, occurring in different degrees. Echocardiography is a valuable tool in detecting RV myocardial abnormalities in this condition. The use of 2D RV4LS, RVFWLS, and 3DEF offers reliable indicators of RV systolic dysfunction in this rare, challenging cardiomyopathy.

Flutter Atrial na Síndrome do PRKAG2: Características Clínicas e Eletrofisiológicas / Atrial Flutter in PRKAG2 Syndrome: Clinical and Electrophysiological Characteristics

Resumo Fundamento A síndrome do PRKAG2 é uma rara doença genética autossômico dominante, fenocópia da miocardiopatia hipertrófica, caracterizada pelo acúmulo intracelular de glicogênio. Manifestações clínicas incluem pré-excitação ventricular, hipertrofia ventricular, distúrbio de condução cardíaca e arritmias atriais. Objetivo Comparar características clínicas e eletrofisiológicas observadas em pacientes com flutter atrial, com e sem síndrome do PRKAG2. Métodos Estudo observacional, comparativo de pacientes com flutter atrial: grupo A, cinco pacientes de família com síndrome do PRKAG2; e grupo B, 25 pacientes sem fenótipo da síndrome. O nível de significância foi de 5%. Resultados Todos os pacientes do grupo A apresentaram pré-excitação ventricular e bloqueio de ramo direito; quatro tinham marca-passo (80%). Pacientes do grupo A tinham menor idade (39±5,4 vs. 58,6±17,6 anos, p=0,021), e maior espessura de septo interventricular (mediana=18 vs. 10 mm; p<0,001) e parede posterior (mediana=14 vs. 10 mm; p=0,001). Quatro do grupo A foram submetidos a estudo eletrofisiológico, sendo observada via acessória fascículo-ventricular; em três foi realizada ablação do flutter atrial. Todos os do grupo B foram submetidos à ablação do flutter atrial, sem evidência de via acessória. Observado maior prevalência no grupo B de hipertensão arterial, diabetes mellitus, doença coronariana e apneia do sono, sem diferença estatisticamente significante. Conclusão Portadores da síndrome do PRKAG2 apresentaram flutter atrial em idade mais precoce, e menos comorbidades, quando comparados a pacientes com flutter atrial sem fenótipo da mutação. Importante suspeitar de miocardiopatia geneticamente determinada, como síndrome do PRKAG2, em jovens com flutter atrial, especialmente na presença de pré-excitação ventricular e hipertrofia ventricular familiar.

Abstract Background PRKAG2 syndrome is a rare autosomal dominant disease, a phenocopy of hypertrophic cardiomyopathy characterized by intracellular glycogen accumulation. Clinical manifestations include ventricular preexcitation, cardiac conduction disorder, ventricular hypertrophy, and atrial arrhythmias. Objective To compare the clinical and electrophysiological characteristics observed in patients with atrial flutter, with and without PRKAG2 syndrome. Methods An observational study comparing patients with atrial flutter: group A consisted of five patients with PRKAG2 syndrome from a family, and group B consisted of 25 patients without phenotype of PRKAG2 syndrome. The level of significance was 5%. Results All patients in group A had ventricular preexcitation and right branch block, and four had pacemakers (80%). Patients in group A were younger (39±5.4 vs 58.6±17.6 years, p=0.021), had greater interventricular septum (median=18 vs 10 mm; p<0.001) and posterior wall thickness (median=14 vs 10 mm; p=0.001). In group A, four patients were submitted to an electrophysiological study, showing a fasciculoventricular pathway, and atrial flutter ablation was performed in tree. All patients in group B were submitted to ablation of atrial flutter, with no evidence of accessory pathway. Group B had a higher prevalence of hypertension, diabetes mellitus, coronary artery disease and sleep apnea, with no statistically significant difference. Conclusion Patients with PRKAG2 syndrome presented atrial flutter at an earlier age and had fewer comorbidities when compared to patients with atrial flutter without mutation phenotype. The occurrence of atrial flutter in young individuals, especially in the presence of ventricular preexcitation and familial ventricular hypertrophy, should raise the suspicion of PRKAG2 syndrome.

Valores de referencia de T1 mapping en individuos sanos en Resonancia Magnética Cardíaca 3.0 Tesla. Relación con edad y sexo. Comparación con diferentes poblaciones / Reference values for T1 mapping in healthy adults at 3.0T. Relation to age and sex. Comparison with different populations

RESUMEN Introducción: El T1 mapping es una técnica que permite mejorar la caracterización tisular por resonancia magnética cardíaca (RMC), y posee creciente evidencia a su favor como herramienta de diagnóstico precoz y estratificación. Presentamos los resultados de la cuantificación del T1 nativo miocárdico en individuos sanos, estudiados en un campo de 3.0 T, a fin de proveer valores de referencia para el medio local. Material y métodos: Se incluyeron 124 individuos consecutivos derivados a nuestro centro para realización de RMC, cuyos estudios resultaron normales. Se midió el T1 mapping en un eje corto medioventricular. Se analizaron los resultados según edad y sexo. Se incluyeron también 27 pacientes con diagnóstico de miocardiopatía hipertrófica, 11 con diagnóstico de miocardiopatía dilatada y 8 con amiloidosis cardíaca. Resultados: Se analizaron 124 estudios. La media global de T1 mapping fue de 1220,7 ± 21,2 mseg. Redondeando a valores enteros, se consideró 1178-1263 mseg como "rango de normalidad" (p5-p95). Se observó un tiempo T1 ligeramente superior en mujeres. No hubo diferencias con respecto a la edad. Se observó una excelente reproducibilidad, evaluada por el coeficiente de correlación intraclase (0,97) y el método de Bland-Altman. Los valores de T1 mapping fueron significativamente superiores en los grupos de individuos portadores de miocardiopatía. Conclusiones: Reportamos valores normales de T1 mapping nativo en una población adulta local. Los mismos son levemente mayores en mujeres, diferencia que no impresiona relevante desde el punto de vista clínico. Al comparar con individuos portadores de miocardiopatía hipertrófica, dilatada o con amiloidosis cardíaca, se obtuvo una muy buena discriminación. La variabilidad interobservador fue muy baja.

ABSTRACT Background: T1mapping is a technique that improves tissue characterization by cardiovascular magnetic resonance (CMR), and there is growing evidence favoring its use as a tool for early diagnosis and stratification. We present the results of native myocardial T1 quantification in a 3.0 T field in healthy individuals, in order to provide local reference values. Methods: A total of 124 consecutive adults with normal studies, referred to our center for CMR, were included in the study. T1 relaxation time was measured in a midventricular short axis slice, analyzing age and sex dependance. For comparison, 27 patients with hypertrophic cardiomyopathy, 11 with dilated cardiomyopathy and 8 with cardiac amyloidosis were also included. Results: Mean global T1mapping of the 124 studies analyzed was 1220.7 ±21.2 msec, and rounding to unity, 1178-1263 msec (p5-p95) was considered as "normal range". A slightly longer T1 time was observed in women and no differences were found with respect to age. Excellent reproducibility was obtained, evaluated by intraclass correlation coefficient (0.97) and BlandAltman plot. T1 mapping values were significantly higher in both groups of individuals with cardiomyopathy. Conclusions: We report normal values of native T1 mapping in a local healthy adult population. Times were slightly higher in women, a difference that was not considered clinically relevant. When comparing with individuals with hypertrophic or dilated cardiomyopathy, a very good discrimination was obtained between the 3 populations. The interobserver variability was very low.

Mecânica Atrial na Cardiomiopatia Hipertrófica: Discriminando Hipertrofia de Fibrose Ventricular / Atrial Mechanics in Hypertrophic Cardiomyopathy: Discriminating between Ventricular Hypertrophy and Fibrosis

Resumo Fundamento A cardiomiopatia hipertrófica (CMH) e a hipertrofia ventricular esquerda (HVE) secundária à hipertensão arterial sistêmica (HAS) podem estar associadas a anormalidades funcionais do átrio esquerdo (AE). Objetivos Caracterizar a mecânica do AE na CMH e na HAS e avaliar qualquer correlação com a extensão da fibrose ventricular esquerda medida por ressonância magnética cardíaca (RMC) em pacientes com CMH. Métodos A função longitudinal do AE derivada do ecocardiograma bidimensional com speckle tracking foi adquirida a partir de cortes apicais de 60 pacientes com CMH e 34 indivíduos controles, pareados por idade. Pacientes com CMH também foram submetidos à RMC, com medida da extensão do realce tardio por gadolínio. A associação com parâmetros de strain do AE foi analisada. Valores p < 0,05 foram definidos como estatisticamente significativos. Resultados A média da fração de ejeção do ventrículo esquerdo não foi diferente entre os grupos. A razão E/e' estava comprometida no grupo CMH e preservada no grupo controle. A mecânica do AE estava significativamente reduzida na CMH em comparação aos pacientes com HAS. O strain rate do AE nas fases de reservatório (SRrAE) e na fase contrátil (SRctAE) foram os melhores parâmetros de discriminação de CMH com uma área sob a curva (AUC) de 0,8, seguido do strain do AE na fase de reservatório (SrAE) (AUC 0,76). O SRrAE e o SRctAE apresentaram elevada especificidade (89% e 91%, respectivamente), e o SrAE apresentou sensibilidade de 80%. Um decréscimo de 2,79% no strain rate do AE na fase de condução (SRcdAE) foi preditor de um aumento de 1 cm na extensão do RT pelo gadolínio (r2=0,42, β 2,79, p=0,027). Conclusões O SRrAE e o SRctAE foram os melhores fatores de discriminação de HVE secundária à CMH. O SRcdAE foi preditor do grau de fibrose ventricular esquerda avaliada por RMC. Esses achados sugerem que a mecânica do AE pode ser um potencial preditor de gravidade de doença na CMH.

Abstract Background Hypertrophic cardiomyopathy (HCM) and left ventricular hypertrophy (LVH) secondary to systemic hypertension (HTN) may be associated with left atrial (LA) functional abnormalities. Objectives We aimed to characterize LA mechanics in HCM and HTN and determine any correlation with the extent of left ventricular (LV) fibrosis measured by cardiac magnetic resonance (CMR) in HCM patients. Methods Two-dimensional speckle tracking-derived longitudinal LA function was acquired from apical views in 60 HCM patients, 60 HTN patients, and 34 age-matched controls. HCM patients also underwent CMR, with measurement of late gadolinium enhancement (LGE) extension. Association with LA strain parameters was analyzed. Statistical significance was set at p<0.05. Results Mean LV ejection fraction was not different between the groups. The E/e' ratio was impaired in the HCM group and preserved in the control group. LA mechanics was significantly reduced in HCM, compared to the HTN group. LA strain rate in reservoir (LASRr) and in contractile (LASRct) phases were the best discriminators of HCM, with an area under the curve (AUC) of 0.8, followed by LA strain in reservoir phase (LASr) (AUC 0.76). LASRr and LASR-ct had high specificity (89% and 91%, respectively) and LASr had sensitivity of 80%. A decrease in 2.79% of LA strain rate in conduit phase (LASRcd) predicted an increase of 1cm in LGE extension (r2=0.42, β 2.79, p=0.027). Conclusions LASRr and LASRct were the best discriminators for LVH secondary to HCM. LASRcd predicted the degree of LV fibrosis assessed by CMR. These findings suggest that LA mechanics is a potential predictor of disease severity in HCM.

Evaluation of correlation between left ventricular changes and left atrial function in hypertrophic cardiomyopathy based on quantitative cardiac MR / 中华放射学杂志

Objective:To explore whether left ventricular interstitial fibrosis is associated with left atrial enlargement and left atrial dysfunction in patients of hypertrophic cardiomyopathy(HCM) with preserved ejection fraction.Methods:From October 2018 to September 2021, 59 HCM including 30 with enlarged maximal left artrial volume index (LAVI max), 29 with normal LAVI max and 28 age-and gender-matched controls were retrospectively enrolled. Imaging protocol included cine sequence, late gadolinium enhancement and T 1 mapping.The relationships between left ventricular mass index (LVMI), quantitative myocardial fibrosis and left atrial-related indexes were analyzed. One-way analysis of variance with Bonferroni post hoc correction or Kruskal-Wallis was performed for continuous variables. Categorical variables were assessed using the Chi-square test or Fisher′s exact test. Pearson or Spearman analysis was used for linear or monotonic nonlinear correlations. Results:The left ventricular end-diastolic volume index, left ventricular end-systolic volume index, left ventricular cardiac output and LVMI of HCM with enlarged LAVI max group were higher than HCM with normal LAVI max group and control group( P<0.05).Correlation analysis showed that LVMI correlated positively with LAVI max( r=0.780, P<0.001) and minimal left artrial volume index (LAVI min) ( r=0.816, P<0.001), extracellular volume correlated positively with LAVI max( r=0.462, P<0.001) and LAVI min( r=0.483, P<0.001),%LGE was correlated positively with LAVI max( r=0.311, P<0.05) and LAVI min( r=0.327, P<0.05),left ventricular index interstitial volume was correlated negatively with left atrial ejection fraction of reservoir ( r=-0.669, P<0.001),left atrial ejection fraction of conduit ( r=-0.472, P<0.001),left atrial ejection fraction of pump ( r=-0.518, P<0.001)and left atrial expansion index( r=-0.626, P<0.001). Conclusion:There is association between LVMI and fibrosis and left atrial enlargement and phases dysfunction in HCM with preserved ejection fraction.

Cardiomiopatia Hipertrófica: uma revisão pelo olhar da ressonância magnética / Hypertrophic Cardiomyopathy: a review using magnetic resonance imaging

A cardiomiopatia hipertrófica é a cardiopatia genética mais frequente na população geral e é caracterizada por uma hipertrofia ventricular esquerda assimétrica. Entretanto, as alterações fenotípicas desta cardiomiopatia vão muito além da hipertrofia ventricular, e incluem alterações do aparato valvar mitral, dos músculos papilares e do ventrículo direito. Devido à dificuldade no diagnóstico diferencial entre as múltiplas causas de hipertrofia, a ressonância magnética cardíaca vem cumprindo um papel fundamental na avaliação diagnóstica e prognóstica desta cardiomiopatia. A cineressonância magnética na definição da localização e extensão da hipertrofia, o realce tardio, na detecção das áreas de fibrose miocárdica e técnicas mais recentes como o Mapa de T1 que avalia a fibrose intersticial e o volume extracelular; e finalmente o Tissue Tracking na análise da deformação miocárdica.(AU)

Hypertrophic cardiomyopathy, the most common genetic cardiopathy in the general population, is characterized by asymmetric left ventricular hypertrophy. However, the phenotypic changes in this cardiomyopathy extend beyond ventricular hypertrophy and include changes in the mitral valve apparatus, papillary muscles, and right ventricle. Due to the difficult differential diagnosis among multiple causes of hypertrophy, cardiac magnetic resonance has played a fundamental role in its diagnostic and prognostic evaluation; magnetic cine-resonance in defining the location and extent of hypertrophy; late enhancement, in the detection of areas of myocardial fibrosis; more recent techniques such as T1 mapping that assesses interstitial fibrosis and extracellular volume; and finally tissue tracking in the analysis of myocardial deformation. (AU)