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

No abstract available.

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.

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.

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.

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.

Retrofitting the Heart: Explaining the Enigmatic Septal Thickening in Hypertrophic Cardiomyopathy.

Hypertrophic cardiomyopathy is the most common genetic cardiac disease and is characterized by left ventricular hypertrophy. Although this hypertrophy often associates with sarcomeric gene mutations, nongenetic factors also contribute to the disease, leading to diastolic dysfunction. Notably, this dysfunction manifests before hypertrophy and is linked to hypercontractility, as well as nonuniform contraction and relaxation (myofibril asynchrony) of the myocardium. Although the distribution of hypertrophy in hypertrophic cardiomyopathy can vary both between and within individuals, in most cases, it is primarily confined to the interventricular septum. The reasons for septal thickening remain largely unknown. In this article, we propose that alterations in muscle fiber geometry, present from birth, dictate the septal shape. When combined with hypercontractility and exacerbated by left ventricular outflow tract obstruction, these factors predispose the septum to an isometric type of contraction during systole, consequently constraining its mobility. This contraction, or more accurately, this focal increase in biomechanical stress, prompts the septum to adapt and undergo remodeling. Drawing a parallel, this is reminiscent of how earthquake-resistant buildings are retrofitted with vibration dampers to absorb the majority of the shock motion and load. Similarly, the heart adapts by synthesizing viscoelastic elements such as microtubules, titin, desmin, collagen, and intercalated disc components. This pronounced remodeling in the cytoskeletal structure leads to noticeable septal hypertrophy. This structural adaptation acts as a protective measure against damage by attenuating myofibril shortening while reducing cavity tension according to Laplace Law. By examining these events, we provide a coherent explanation for the septum's predisposition toward hypertrophy.

Understanding transcatheter edge-to-edge repair "knobology": Advanced catheter steering for different scenarios of transseptal puncture.

Following the introduction in the latest European and American guidelines, transcatheter edge-to-edge repair has become a valid alternative to surgery for ineligible patients. Among the available technologies, MitraClip (Abbott) was the first to be introduced for the percutaneous treatment of mitral regurgitation with the edge-to-edge technique. Although its safety and effectiveness has been widely demonstrated, the optimal procedural results are highly dependent from operators' experience. In this manuscript, we provide a full guide of advanced steering maneuvers of MitraClip in different scenarios of transseptal puncture.

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.

A Comparison of the Association of Septal Scar Burden on Responses to LBBAP-CRT and BVP-CRT.

BACKGROUND: Left bundle branch area pacing (LBBAP) is an alternative to biventricular pacing (BVP) for cardiac resynchronization therapy (CRT). However, despite the presence of left bundle branch block, whether cardiac substrate may influence the effect between the 2 strategies is unclear. OBJECTIVES: This study aims to assess the association of septal scar on reverse remodeling and clinical outcomes of LBBAP compared with BVP. METHODS: We analyzed patients with nonischemic cardiomyopathy who had CRT indications undergoing preprocedure cardiac magnetic resonance examination. Changes in left ventricular ejection fraction (LVEF) and echocardiographic response (ER) (≥5% absolute LVEF increase) were assessed at 6 months. The clinical outcome was the composite of all-cause mortality, heart failure hospitalization, or major ventricular arrhythmia. RESULTS: There were 147 patients included (51 LBBAP and 96 BVP). Among patients with low septal scar burden (below median 5.7%, range: 0% to 5.3%), LVEF improvement was higher in the LBBAP than the BVP group (17.5% ± 10.9% vs 12.3% ± 11.8%; P = 0.037), with more than 3-fold increased odds of ER (OR: 4.35; P = 0.033). In high sepal scar subgroups (≥5.7%, range: 5.7%-65.9%), BVP trended towards higher LVEF improvement (9.2% ± 9.4% vs 6.4% ± 12.4%; P = 0.085). Interaction between septal scar burden and pacing strategy was significant for ER (P = 0.002) and LVEF improvement (P = 0.011) after propensity score adjustment. During median follow-up of 33.7 (Q1-Q3: 19.8-42.1) months, the composite clinical outcome occurred in 34.7% (n = 51) of patients. The high-burden subgroups had worse clinical outcomes independent of CRT method. CONCLUSIONS: Remodeling response to LBBAP and BVP among nonischemic cardiomyopathy patients is modified by septal scar burden. High septal scar burden was associated with poor clinical prognosis independent of CRT methods.

Myocardial perfusion improvement and mechanism after percutaneous intramyocardial septal radiofrequency ablation in obstructive hypertrophic cardiomyopathy: a study of myocardial contrast echocardiography.

The data on myocardial perfusion of the percutaneous intramyocardial septal radiofrequency ablation (PIMSRA) for obstructive hypertrophic cardiomyopathy (HOCM) are still lacking, although PIMSRA have been proved to be of great safety and efficacy. The aim of this study was to quantitatively analyze the changes in myocardial perfusion after PIMSRA using myocardial contrast echocardiography (MCE). 27 HOCM patients treated with PIMSRA were retrospectively analyzed, and their echocardiographic parameters and perfusion parameters of MCE were collected before and 12 months after PIMSRA. A reperfusion curve was used to quantify microvascular blood volume (A), microvascular flux rate (ß), and microvascular blood flow (MBF) of each segment. Then the value difference (Δ) of parameters between post- and pre-operation were calculated. Finally, the correlation between the changes in MBF and in each echocardiographic parameter was analyzed. (1) Compared with baseline, the global A, ß and MBF were significantly increased in HOCM patients after PIMSRA (all P < 0.001). The ß, MBF were increased in the interventricular septum (P < 0.001, respectively), and the A, ß, MBF were increased in the left ventricular wall (all P < 0.001). (2) Correlation analysis showed that the ΔMBF of interventricular septum was mainly negatively correlated with the maximum interventricular septum thickness (ΔIVSTmax, r=-0.670, P < 0.001), mean interventricular septum thickness (ΔIVSTmean, r=-0.690, P < 0.001), and left ventricular mass index (ΔLVMI, r=-0.774, P < 0.001), while the ΔMBF of left ventricular wall was positively correlated with left ventricular end-diastolic volume index (ΔLVEDVI, r = 0.621, P = 0.001) and stroke volume index (ΔSVI, r = 0.810, P < 0.001). Myocardial perfusion was improved at both interventricular septum and ventricular wall in HOCM patients after PIMSRA. MCE can provide a new dimension for the efficacy evaluation to PIMSRA procedure.

Transseptal coronary artery-a pictorial review.

A transseptal coronary artery course, also known as a transconal course, is an anomalous course of the left main coronary artery (LMCA) or the left anterior descending artery (LAD) through the conal septal myocardium. The conal septal myocardium is the posterior wall of the right ventricular outflow tract (RVOT), acting as a dividing myocardial wall between the subaortic and subpulmonary outflow tracts. The initial segment of a transseptal coronary artery has an extraconal course between the aorta and the RVOT cranial to the true intramyocardial segment. The transseptal coronary artery then emerges out of the conal septal myocardium at the epicardial surface on the lateral aspect of the RVOT. Many consider the transseptal coronary artery to be a benign entity. However, there are few case reports of severe cardiac symptoms such as myocardial ischemia, arrhythmia, and even sudden cardiac deaths due to potential coronary artery compression in the systolic phase.​ In this article, we seek to describe the imaging findings of transseptal coronary artery course on coronary computed tomography angiography (CTA), discuss their clinical analysis, and briefly discuss the management of these lesions.

Clinical characteristics and outcomes of alcohol septal ablation in the era of transcatheter valve interventions.

BACKGROUND: The clinical efficacy and safety of alcohol septal ablation (ASA) for obstructive hypertrophic cardiomyopathy (HCM) have been well-established; however, less is known about outcomes in patients undergoing preemptive ASA before transcatheter mitral valve replacement (TMVR). AIMS: The goal of this study is to characterize the procedural characteristics and examine the clinical outcomes of ASA in both HCM and pre-TMVR. METHODS: This retrospective study compared procedural characteristics and outcomes in patient who underwent ASA for HCM and TMVR. RESULTS: In total, 137 patients were included, 86 in the HCM group and 51 in the TMVR group. The intraventricular septal thickness (mean 1.8 vs. 1.2 cm; p < 0.0001) and the pre-ASA LVOT gradient (73.6 vs. 33.8 mmHg; p ≤ 0.001) were higher in the HCM group vs the TMVR group. The mean volume of ethanol injected was higher (mean 2.4 vs. 1.7 cc; p < 0.0001). The average neo-left ventricular outflow tract area increased significantly after ASA in the patients undergoing TMVR (99.2 ± 83.37 mm2 vs. 196.5 ± 114.55 mm2; p = <0.0001). The HCM group had a greater reduction in the LVOT gradient after ASA vs the TMVR group (49.3 vs. 18 mmHg; p = 0.0040). The primary composite endpoint was higher in the TMVR group versus the HCM group (50.9% vs. 25.6%; p = 0.0404) and had a higher incidence of new permanent pacemaker (PPM) (25.5% vs. 18.6%; p = 0.3402). The TMVR group had a higher rate of all-cause mortality (9.8% vs. 1.2%; p = 0.0268). CONCLUSIONS: Preemptive ASA before TMVR was performed in patients with higher degree of clinical comorbidities, and correspondingly is associated with worse short-term clinical outcomes in comparison to ASA for HCM patients. ASA before TMVR enabled percutaneous mitral interventions in a small but significant minority of patients that would have otherwise been excluded. The degree of LVOT and neoLVOT area increase is significant and predictable.