Long-Term Outcomes After Septal Reduction Therapies in Obstructive Hypertrophic Cardiomyopathy: Insights From the SHARE Registry.

BACKGROUND: Septal reduction therapy (SRT) provides substantial symptomatic improvement in patients with obstructive hypertrophic cardiomyopathy (HCM). However, long-term disease course after SRT and predictors of adverse outcomes have not been systematically examined. METHODS: Data from 13 high clinical volume HCM centers from the international SHARE (Sarcomeric Human Cardiomyopathy Registry) were analyzed. Patients were followed from the time of SRT until last follow-up or occurrence of heart failure (HF) composite outcome (cardiac transplantation, implantation of a left ventricular assist device, left ventricular ejection fraction <35%, development of New York Heart Association class III or IV symptoms), ventricular arrhythmias composite outcome (sudden cardiac death, resuscitated cardiac arrest, or appropriate implantable cardioverter defibrillator therapy), or HCM-related death. Cox proportional hazards models were used to identify predictors of outcome. RESULTS: Of the 10 225 patients in SHARE, 1832 (18%; 968 [53%] male) underwent SRT, including 455 (25%) with alcohol septal ablation and 1377 (75%) with septal myectomy. The periprocedural 30-day mortality rate was 0.4% (8 of 1832) and 1499 of 1565 (92%) had a maximal left ventricular outflow tract gradient <50 mm Hg at 1 year. After 6.8 years (range, 3.4-9.8 years; 12 565 person-years) from SRT, 77 (4%) experienced HCM-related death (0.6% per year), 236 (13%) a composite HF outcome (1.9% per year), and 87 (5%) a composite ventricular arrhythmia outcome (0.7% per year). Among adults, older age at SRT was associated with a higher incidence of HCM death (hazard ratio, 1.22 [95 CI, 1.1-1.3]; P<0.01) and the HF composite (hazard ratio, 1.14 [95 CI, 1.1-1.2] per 5-year increase; P<0.01) in a multivariable model. Female patients also had a higher risk of the HF composite after SRT (hazard ratio, 1.4 [95 CI, 1.1-1.8]; P<0.01). De novo atrial fibrillation occurred after SRT in 387 patients (21%). Among pediatric patients followed for a median of 13 years after SRT, 26 of 343 (16%) developed the HF composite outcome, despite 96% being free of recurrent left ventricular outflow tract obstruction. CONCLUSIONS: Successful short- and long-term relief of outflow tract obstruction was observed in experienced multidisciplinary HCM centers. A subset of patients progressed to develop HF, but event-free survival at 10 years was 83% and ventricular arrhythmias were rare. Older age, female sex, and SRT during childhood were associated with a greater risk of developing HF.

A preoperative planning procedure of septal myectomy for hypertrophic obstructive cardiomyopathy using image-based computational fluid dynamics simulations and shape optimization.

Although septal myectomy is the preferred treatment for medication-refractory hypertrophic obstructive cardiomyopathy (HOCM), the procedure remains subjective. A preoperative planning procedure is proposed using computational fluid dynamics simulations and shape optimization to assist in the objective assessment of the adequacy of the resection. 3 patients with HOCM were chosen for the application of the proposed procedure. The geometries of the preoperative left ventricular outflow tract (LVOT) of patients in the systolic phase were reconstructed from medical images. Computaional fluid dynamics (CFD) simulations were performed to assess hemodynamics within LVOT. Sensitivity analysis was performed to determine the resection extent on the septal wall, and the depth of the resection was optimized to relieve LVOT obstruction while minimizing damage to the septum. The optimized resection was then transferred from systole to diastole to provide surgeons with instructive guidance for septal myectomy. Comparison between preoperative and postoperative hemodynamics showed an evident improvement with respect to the pressure gradient throughout the LVOT. The resected myocardium in the diastolic phase is more extended and thinner than its state in the systolic phase. The proposed preoperative planning procedure may be a viable addition to the current preoperative assessment of patients with HOCM.

[Prevalence of transthyretin cardiac amyloidosis in patients hospitalized for heart failure with preserved ejection fraction and septal thickness]. / Prevalencia de amiloidosis cardíaca por transtiretina en pacientes internados por insuficiencia cardíaca con fracción de eyección preservada y engrosamiento septal.

INTRODUCTION: Transthyretin cardiac amyloidosis (ATTR-CM) usually presents as heart failure with preserved ejection fraction. Its diagnosis has a significant clinical impact, as specific treatment is currently available. The aim of this study is to assess the prevalence of ATTR-CM in patients hospitalized for heart failure with preserved ejection fraction and septal thickness in our region. METHODS: Cross-sectional study. Patients over 18 years old hospitalized for heart failure with preserved ejection fraction (greater than 50%) and septal thickness greater than or equal to 12 mm during the period from 8/2019 to 1/2023 were prospectively included. A pyrophosphate bone scintigraphy (PYP) was planned to assess cardiac involvement. The prevalence of ATTR-CM and its 95% confidence interval were calculated. RESULTS: A PYP was performed in 59/82 patients. The median age was 85 [IQR 78-88] years old, 54% women. On admission, 61% had atrial fibrillation/flutter rhythm and the median NT-Pro-Bnp was 3536 [IQR 1700-7748] pg/nl. The mean ejection fraction was 57% (± 5). The prevalence of ATTR-CM diagnosed by bone scintigraphy with PYP was 19% (95%CI 9.7-30.1). No differences were found compared with those patients who did not perform a PYP. CONCLUSION: In patients admitted for heart failure with preserved ejection fraction and septal thickness, the diagnosis of ATTR-CM was relatively common (1/5). We believe that it should be routinely explored.

Introducción: La amiloidosis cardíaca por transtiretina (TTR) se suele presentar como insuficiencia cardiaca (IC) con fracción de eyección preservada. Diagnosticarla tiene impacto clínico, ya que actualmente se dispone de tratamiento específico. El objetivo de este estudio fue evaluar la prevalencia en nuestro medio de TTR en pacientes hospitalizados por IC con función sistólica preservada e hipertrofia septal. Métodos: Estudio de corte transversal. Se incluyeron de forma prospectiva pacientes mayores a 18 años internados por IC con función sistólica conservada (fracción de eyección mayor a 50%) y espesor septal mayor o igual a 12 mm durante el periodo del 8/2019 a 1/2023. El compromiso cardiaco se evaluó mediante un centellograma óseo con pirofosfato (PYP) Se calculó la prevalencia de amiloidosis por TTR y su IC95%. Resultados: Se efectuó un centellograma en 59/82 pacientes. La edad fue de 85 [RIC 78-88] años, el 54% mujeres. Al ingreso, el 61% presentó ritmo de fibrilación/aleteo auricular y una mediana de NT-Pro-Bnp de 3536 pg/ml [RIC 1700-7748 pg/nl]. La media de fracción de eyección fue de 57 (± 5) %. La prevalencia de amiloidosis cardiaca por TTR diagnosticada por centellograma óseo con PYP fue del 19% (IC95% 9,7-30,1). No se detectaron diferencias con los 23 pacientes que no efectuaron centellograma. Conclusiones: En pacientes internados por IC con fracción de eyección preservada y engrosamiento septal el diagnóstico de amiloidosis cardiaca por TTR fue relativamente frecuente (1/5), por lo que consideramos que debería explorarse en forma rutinaria.

It has been 30 years since the first alcohol septal ablation for hypertrophic obstructive cardiomyopathy was performed.

No abstract available.

Septal Ablation to Treat Subaortic Dynamic Obstruction Following Transcatheter Aortic Valve Implantation.

Dynamic obstruction of the left ventricle is an unusual complication that can occur after aortic valve replacement. It is important to be aware of this pathology as it requires different management than normal complications and can rapidly lead to death. We present a case of successful resolution following transcatheter aortic valve implantation.

Midterm Outcomes of Percutaneous Intramyocardial Septal Radiofrequency Ablation for Hypertrophic Cardiomyopathy: A Single-Center, Observational Study.

BACKGROUND: Percutaneous intramyocardial septal radiofrequency ablation (PIMSRA) has been reported to be safe and effective at midterm follow-up to treat drug-refractory hypertrophic obstructive cardiomyopathy in a single center. However, data from other centers are lacking. This retrospective cohort study aimed to investigate the efficacy and safety of PIMSRA from another independent center. METHODS AND RESULTS: PIMSRA was performed in 76 patients with hypertrophic obstructive cardiomyopathy in our center from April 2020 to June 2023. The primary outcome was the reduction of left ventricular outflow tract gradient after 6 months or more post-PIMSRA. Secondary outcomes were periprocedural major adverse clinical events. Sixty-one patients returned to the hospital for follow-up 6 to 30 (median, 14) months after the procedure. At the last follow-up of the 61 patients, the maximum septal thickness decreased from a median of 23.6 (interquartile range, 20.5-26.4) to 19.1 (interquartile range, 16.0-22.1) mm (P<0.001) and the left ventricular outflow tract peak gradient at rest decreased from a median of 70.0 (interquartile range, 29.1-107.5) to 20.0 (interquartile range, 10.8-48.8) mm Hg (P<0.001). The percentage of patients with symptoms of New York Heart Association functional class III/IV decreased from 51% to 0%. Of all 76 patients, there was no in-hospital or 30-day death, no right or left branch block, and no permanent pacemaker implantation. Six (8%) patients had pericardial effusion, with 1 experiencing cardiac tamponade and ventricular fibrillation, and 1 (1%) patient developed septal branch aneurysm that was treated with coil occlusion. CONCLUSIONS: PIMSRA allows for the reduction in the left ventricular outflow tract gradient and enhances symptomatic improvement, with a limited incidence of adverse events and complications among patients with hypertrophic obstructive cardiomyopathy.

Analysis of risk factors for complications in echocardiography-guided percutaneous intramyocardial septal radiofrequency ablation.

BACKGROUND: The feasibility of percutaneous intramyocardial septal radiofrequency ablation (PIMSRA) for the treatment of hypertrophic obstructive cardiomyopathy (HOCM) has been previously reported. However, limited investigation has been conducted regarding the complications associated with this procedure. OBJECTIVE: This study aims to analyze the risk factors affecting the occurrence of complications during PIMSRA, such as pericardial effusion, ventricular premature beats, and interventricular septal perforation. In this study, the optimal cut-off values for these risk factors are also explored, and corresponding strategies for prevention are proposed. METHODS: A total of 101 patients diagnosed with HOCM who underwent the PIMSRA procedure from 2021 to 2022 were included in this retrospective analysis. Patients were classified into subgroups with or without complications based on procedural records. Univariate and multivariate regression analyses were conducted to identify independent risk factors for complications during the PIMSRA procedure. RESULTS: There were 48 patients with complications and 53 patients without complications. The heart rate at the start of the procedure and the maximum left ventricular outflow tract gradient (LVOTG) were independent risk factors related to PIMSRA complications. The optimal cut-off values for predicting complication occurrence were a heart rate > 49 bpm at the start of the procedure (OR: 3.79, 95% CI: 1.64-8.78, p = 0.002) and a maximum LVOTG > 92 mmHg (OR: 2.57, 95% CI: 1.15-5.75, p = 0.022), respectively. CONCLUSIONS: The occurrence of PIMSRA complications is primarily associated with the heart rate at the start of the procedure and the maximum LVOTG. It is recommended to establish a comprehensive control plan to minimize the risk of complications during PIMSRA procedures.

Evaluating the Prevalence of Cardiac Surgery-associated Acute Kidney Injury After Septal Myectomy Combined With Concomitant Procedures in Obstructive Hypertrophic Cardiomyopathy.

OBJECTIVES: Hypertrophic obstructive cardiomyopathy (HOCM) may be treated by septal myectomy. Cardiac surgery-associated acute kidney injury (CSA-AKI) is a common complication, but little is known about its incidence after septal myectomy. The objectives of this work were to evaluate the prevalence of CSA-AKI after septal myectomy and identify potential perioperative and phenotype-related factors contributing to CSA-AKI. DESIGN: This was a retrospective database analysis with new data analysis. SETTING: The study occurred in a single university academic expertise center for septal myectomy HOCM patients. PARTICIPANTS: Data from 238 HOCM patients with septal myectomy operated on between 2005 and 2022 were collected. INTERVENTIONS: CSA-AKI was stratified according to the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines using measurement of creatinine and urine production. Important HOCM phenotype-related and perioperative factors were analyzed for their possible associations with CSA-AKI. MEASUREMENTS AND MAIN RESULTS: CSA-AKI occurred in 45% of patients; of these, 55% were classified as KDIGO stage I and the remaining 45% as stage II, with no chronic kidney damage observed. Moreover, there were no phenotypical or perioperative characteristics that were more prevalent in the CSA-AKI cohort. However, the use of beta-blockers and coronary artery disease were more prevalent in the CSA-AKI cohort. CONCLUSIONS: CSA-AKI is a common complication after septal myectomy but was transient, and kidney function recovered in all patients.

Outcomes after septal myectomy in a cohort of patients with hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) with left ventricular outflow tract obstruction that doesn't improve with pharmacological management often requires septal myectomy. However, there are few centers with experience in the practice of this procedure in our country. We describe the clinical and echocardiographic characteristics and postoperative outcomes of patients with HCM indicated for septal myectomy at a reference center in Colombia. MATERIALS AND METHODS: Retrospective cohort study. Patients undergoing septal myectomy between 2010 and 2023 were included. Data were collected before and two years after surgery. RESULTS: 18 patients were included. The mean age was 50 years. The predominant functional class was NYHA II/III (94 %). Asymmetric septal variant (83.3 %) was the most frequent as well as obstructive phenotype (88.8 %). After myectomy, 70.5 % improved to NYHA I and 62.4 % had no significant gradient (<30 mmHg), and the most of patient improved SAM. One patient died post-procedure, anymore complications were presented. DISCUSSION/CONCLUSIONS: Septal myectomy is a safe procedure, with clinical and echocardiographic improvement, with low complication rates.

Feasibility and safety of percutaneous intramyocardial septal cryoablation: A canine model with 6-month follow-up.

Echocardiography-guided percutaneous intramyocardial septal radiofrequency ablation (PIMSRA, Liwen procedure) is a novel treatment option for hypertrophic obstructive cardiomyopathy (HOCM). The safety and feasibility of using this procedure for cryoablation are unknown. We aimed to investigate the feasibility and safety of echocardiography-guided percutaneous intramyocardial septal cryoablation (PIMSCA) for septal thickness reduction in a canine model. Eight canines underwent PIMSCA, and had electrocardiography, echocardiography(ECG), myocardial contrast echocardiography (MCE), serological and pathological examinations during the preoperative, immediate postoperative, and 6-month follow-up. All eight canines underwent successful cryoablation and continued to be in sinus rhythm during ablation and without malignant arrhythmias. MCE showed that the ablation area had decreased myocardial perfusion after the procedure. Troponin I levels were significantly elevated [0.010 (0.005, 0.297) ng/mL vs. 3.122 (1.152, 7.990) ng/mL, p < 0.05)]. At 6-month follow-up after the procedure, all animals were alive, with thinning of the interventricular septum (7.26 ± 0.52 mm vs. 3.86 ± 0.29 mm, p < 0.05). Echocardiography showed no significant decrease in the left ventricular ejection fractions (LVEF) (54.32 ± 2.93 % vs. 54.70 ± 2.47 %, p > 0.05) or changes by pulse-wave Doppler E/A (1.17 ± 0.43 vs. 1.07 ± 0.43, p > 0.05), E/e' (8.09 ± 1.49 vs. 10.05 ± 2.68, p > 0.05). Pathological findings proved the effectiveness of cryoablation in myocardial tissues. We observed pericardial effusions and premature ventricular complexes (PVCs) associated with the procedure. Our findings provided preliminary evidence of the safety and feasibility of PIMSCA in reducing interventricular septum, which provides a potentially new treatment option for HOCM.

Alcohol septal ablation for hypertrophic obstructive cardiomyopathy: do mitral valve leaflet length, septal thickness, or sex affect the outcome?

This retrospective cohort study aimed to assess whether basal septal wall thickness (BSWT), anterior (AML) and posterior (PML) mitral leaflet length, or sex were associated with remaining left ventricular outflow tract obstruction (LVOTO) in patients with hypertrophic obstructive cardiomyopathy (HOCM) undergoing alcohol septal ablation (ASA). One hundred fifty-four patients who underwent ASA at the Karolinska University Hospital in Stockholm, Sweden, between 2009 and 2021, were included retrospectively. Anatomical and hemodynamic parameters were collected from invasive catheterization before and during ASA, and from echocardiography (ECHO) examinations before, during, and at 1-year follow-up after ASA. Linear and logistic regression models were used to assess the association between sex, BSWT, AML, PML, and outcome, which was defined as the remaining LVOTO (≥ 30 mmHg) after ASA. The median follow-up was 364 days (interquartile range 334-385 days). BSWT ≥ 23 mm (n = 13, 12%) was associated with remaining LVOTO at follow-up (p = 0.004). Elongated mitral valve leaflet length (either AML or PML) was present in 125 (90%) patients. Elongated AML (> 24 mm) was present in 67 (44%) patients, although AML length was not associated with remaining LVOTO at follow-up. Elongated PML (> 14 mm) was present in 114 (74%) patients and was not associated with remaining LVOTO at follow-up. No significant sex differences were observed regarding the remaining LVOTO. ECHO measurement of BSWT can be effectively used to select patients for successful ASA and identify those patients with a risk of incomplete resolution of LVOTO after ASA.

Septal venous channel perforation during left bundle branch area pacing: a prospective study.

AIMS: To characterize the diagnosis, frequency, and procedural implications of septal venous channel perforation during left bundle branch area pacing (LBBAP). METHODS AND RESULTS: All consecutive patients undergoing LBBAP over an 8-month period were prospectively studied. During lead placement, obligatory septal contrast injection was performed twice, at initiation (implant entry zone) and at completion (fixation zone). An intuitive fluoroscopic schema using orthogonal views (left anterior oblique/right anterior oblique) and familiar landmarks is described. Using this, we resolved zonal distribution (I-VI) of lead position on the ventricular septum and its angulation (post-fixation angle θ). Subjects with and without septal venous channel perforation were compared. Sixty-one patients {male 57.3%, median age [interquartile range (IQR)] 69.5 [62.5-74.5] years} were enrolled. Septal venous channel perforation was observed in eight (13.1%) patients [male 28.5%, median age (IQR) 64 (50-75) years]. They had higher frequency of (i) right-sided implant (25% vs. 1.9%, P = 0.04), (ii) fixation in zone III at the mid-superior septum (75% vs. 28.3%, P = 0.04), (iii) steeper angle of fixation-median θ (IQR) [19 (10-30)° vs. 5 (4-19)°, P = 0.01], and (iv) longer median penetrated-lead length (IQR) [13 (10-14.8) vs. 10 (8.5-12.5) mm, P = 0.03]. Coronary sinus drainage of contrast was noted in five (62.5%) patients. Abnormal impedance drops during implantation (12.5% vs. 5.7%, P = NS) were not significantly different. CONCLUSION: When evaluated systematically, septal venous channel perforation may be encountered commonly after LBBAP. The fiducial reference framework described using fluoroscopic imaging identified salient associated findings. This may be addressed with lead repositioning to a more inferior location and is not associated with adverse consequence acutely or in early follow-up.

Sex-Related Differences in Patients With Hypertrophic Cardiomyopathy Undergoing Alcohol Septal Ablation.

BACKGROUND: Previous studies have shown that women with hypertrophic obstructive cardiomyopathy (HCM) have worse long-term outcomes irrespective of intervention. However, the outcomes of patients undergoing alcohol septal ablation (ASA) based on sex have not been described. Hence, this study aimed to evaluate pressure changes and long-term mortality in patients with HCM undergoing ASA based on sex. METHODS AND RESULTS: This is a single-center retrospective study evaluating hemodynamic changes and long-term mortality in patients with HCM treated with ASA according to sex. A total of 259 patients were included (aged 68.4±11.9 years, 62.2% women). Women had higher age and baseline pressures at the time of ASA, with a greater percent reduction in mean left atrial pressure (men versus women: 2.2% versus 15.9%, respectively; P=0.02). Women had better survival (median survival rate of men versus women: 8.6 versus 12.5 years, respectively; P=0.011). On Cox multivariable regression, predictors of mortality were age (per group change <60 years, 61-70 years, 71-80 years, and >80 years; hazard ratio [HR], 1.45 [95% CI, 1.10-1.91], P=0.008), female sex (HR, 0.59 [95% CI, 0.35-0.99], P=0.048), chronic kidney disease (HR, 1.88 [95% CI, 1.06-3.33], P=0.031), and left ventricular outflow tract gradient reduction ≤86% (HR, 1.91 [95% CI, 1.14-3.19], P=0.014). CONCLUSIONS: Women with HCM undergoing ASA are older and have higher left-sided baseline pressures compared with men yet have better survival. Further studies exploring the mechanisms of differential outcomes according to sex in patients with HCM undergoing ASA are needed.