Drug-refractory Hypertrophic Obstructive Cardiomyopathy Research Articles

Short time effects of two radiofrequency ablation methods on hypertrophic obstructive cardiomyopathy.

Radiofrequency ablation has been applied for the treatment of hypertrophic obstructive cardiomyopathy (HOCM). The two known procedures are percutaneous intramyocardial septal radiofrequency ablation (PIMSRA) and endocardial radiofrequency septal ablation (ERSA). This study presents a retrospective analysis of the PIMSRA and ERSA procedures in patients with drug-refractory HOCM. A total of 28 patients participated in the study, with 12 receiving PIMSRA and 16 receiving ERSA. The objective of our study was to compare the short-term effects of these two radiofrequency ablation procedures. At the 30-day follow-up, the PIMSRA group demonstrated a greater reduction in left ventricular outflow tract peak gradient at rest compared to the ERSA group (22.25 [16.72] mmHg versus 47.75 [21.94] mmHg) (p < .01). The values for the PIMSRA group decreased from 99.33 (32.00) mmHg to 22.25 (16.72) mmHg (p < .01), while the ERSA group decreased from 97.75 (30.24) mmHg to 47.75 (21.94) mmHg (p < .01). Only the PIMSRA group exhibited a decrease in mitral regurgitation (MR). The area of MR decreased from 10.13 (4.12) mm2 to 3.65 (2.80) mm2 in the PIMSRA group (p < .01). Additionally, the PIMSRA group experienced reductions in left atrial diameter (LAD) and left ventricular ejection fraction (LVEF)%. The values for LAD changed from 43.58 (7.53) mm to 37.08 (6.92) mm (p = .03), and the values for LVEF% decreased from 65.75 (6.12) pg/mL to 60.83 (4.06) pg/mL (p = .03). In terms of the two types of radiofrequency ablation methods used in HOCM, it has been observed that PIMSRA demonstrates a more favorable early treatment effect compared to ERSA.

Comparative Evaluation of Alcohol Septal Ablation: Left Anterior Descending Versus Non-left Anterior Descending Artery Approaches

Alcohol septal ablation (ASA) is performed for symptomatic drug-refractory hypertrophic obstructive cardiomyopathy to reduce the left ventricular outflow tract pressure gradient (LVOTPG) by injecting ethanol into a septal branch that perforates the septal bulge. The target septal branches usually arise directly from the left anterior descending (LAD) artery; however, vessels from a non-LAD artery can be selected in some cases. This study aimed to compare effectiveness and safety between ASA performed using a septal branch arising from a non-LAD artery and a branch arising from the LAD artery. This single-center, retrospective, observational cohort study comprised patients with hypertrophic obstructive cardiomyopathy who underwent ASA at the Gifu Heart Centre between 2011 and 2022. The effectiveness and safety of ASA using the 2 artery types were compared. The primary endpoints were LVOTPG and procedure success, determined as LVOTPG <30 mmHg after 1 year. Of 33 patients (mean age: 66.4 ± 13.0 years; 13 males), 18 patients who underwent ASA using only LAD branches and 15 patients who underwent ASA using only non-LAD branches demonstrated no significant difference in the decrease in LVOTPG during the follow-up period (−99.1 ± 47.4 mmHg/year vs. −75.7 ± 39.2 mmHg/year, respectively, P = 0.19). The procedure success at 1 year was not significantly different between the 2 groups (93.3% and 84.6%, respectively, P = 0.58). ASA performed using septal branches from non-LAD arteries could be an alternative treatment approach when appropriate septal branches are missing or desirable effects cannot be obtained from ASA using LAD branches.

Abstract 14235: Alcohol Septal Ablation Using Septal Branches From the Non-Left Anterior Descending Artery Demonstrates Similar Effectiveness Compared to Septal Branches From Left Anterior Descending Artery

Introduction: Alcohol septal ablation (ASA) is performed on symptomatic, drug-refractory hypertrophic obstructive cardiomyopathy to reduce pressure gradient in the left ventricular outflow tract (LVOT), usually using the major septal branch from the left anterior descending (LAD) artery. In some cases, a septal branch from other than LAD may be selected as an alternative target that perfuses the basal septum. The aim of this study is to evaluate the effectiveness and safety of ASA using non-LAD branches compared to ASA using major branches directly from the LAD. Methods: We conducted a single-center, retrospective, observational cohort study comprising patients who underwent ASA between 2011 and 2023. The primary outcome was the success rate, defined as a pressure gradient in the LVOT of less than 30 mmHg one year after ASA. The secondary outcomes were all-cause death, cardiac rehospitalization, and newly-developed conduction system disorders. Results: The study enrolled 36 patients (age: 66.6± 12.7 years; 13 men), and pressure gradients in LVOT before ASA were not significantly different in the two groups (76±50 mmHg in the non-LAD group (n =17) vs. 76±39 mmHg in the LAD group (n = 19), p= 0.90). The non-LAD and LAD groups had similar success rates of 88.2 % and 86.7 %, respectively, at one year (p &gt; 0.99). The decrease in the pressure gradient in LVOT was similarly observed in both groups (61±44 mmHg in the non-LAD group vs. 61±35 mmHg in the LAD group, p=0.87). No patient died in either group within one year following ASA. The study found a non-significant incidence of newly-developed conduction system disorder (11.8 % in the non-LAD group vs. 5.3 % in the LAD group, P= 0.92). Conclusions: ASA using the non-LAD artery demonstrated similar effectiveness in decreasing the pressure gradient in the LVOT and similar safety compared to using the septal branch from the LAD at one year. Therefore, the non-LAD artery may become an alternative option for the target vessel in ASA.

Long-term outcomes of surgery for obstructive hypertrophic cardiomyopathy in a pediatric cohort

BackgroundSeptal reduction therapy via septal myectomy or a modified Konno procedure is the mainstay of therapy for drug-refractory obstructive hypertrophic cardiomyopathy (HCM), although outcomes data on septal myectomy in pediatric patients are limited. We evaluated long-term outcomes following surgery for obstructive HCM in a pediatric cohort. MethodsWe retrospectively reviewed patients age ≤18 years with obstructive HCM who underwent a left and/or right ventricular septal myectomy at our institution between 1992 and 2022. Primary endpoints were transplantation-free survival, freedom from HCM-related death, and cumulative probability of HCM-related reintervention. We further evaluated outcomes in patients with and without Noonan syndrome or other RASopathies. ResultsThirty-seven patients (median age, 7.4 years; interquartile range [IQR], 3.4-12.9 years) underwent transaortic septal myectomy. A combined modified Konno procedure was performed in 5 patients (13.9%). Sixteen patients (43.2%) had a RASopathy. A concomitant right ventricular outflow tract resection was performed in 9 patients (24.3%). There was 1 (2.7%) in-hospital death and 4 late deaths at a median follow-up of 10.5 years (IQR, 0.1-29.3). Twenty-year transplant-free survival and freedom from HCM-related death were 80.6% (95% confidence interval [CI], 64.2%-100%) and 87.1% (95% CI, 71.8%-100%), respectively. The 20-year cumulative probability of HCM-related reintervention was 34.2% (95% CI, 12.8%-57.1%). Seven patients required a septal reintervention. There was no difference in any primary endpoints between patients with and without a RASopathy. ConclusionsSurgery for obstructive HCM, including septal myectomy with and without a modified Konno procedure, may be performed with low morbidity and good long-term outcomes in pediatric patients. Recurrent outflow tract obstruction is not uncommon.

Hemodynamic Predictors of Outcome Following Alcohol Septal Ablation for Hypertrophic Obstructive Cardiomyopathy.

Alcohol septal ablation (ASA) is a minimally invasive treatment for drug-refractory obstructive hypertrophic cardiomyopathy. Detailed assessment of pressure changes and predictors of mortality and procedure success are not well defined. This is a single-center study evaluating pressure changes and predictors of mortality and procedure success in transseptal ASA. Survival analysis and predictors of mortality were assessed using the Kaplan-Meier analysis and Cox regression, respectively. A total of 156 patients were included (mean age, 67.3 years; 46.8% women). Left atrial (LA) pressure and left ventricular outflow tract (LVOT) gradient decreased, whereas aortic pulse pressure (PP) increased post-ASA. Patients with lower baseline mean LA pressure (<median, 19 mm Hg), LVOT gradient reduction >82% (gradient change median), and PP increase >19% (PP change median) had superior survival. On Cox univariable regression, baseline mean LA pressure >median (19 mm Hg; hazard ratio [HR], 2.09 [95% CI, 1.05-4.18]; P=0.036), residual LVOT gradient (HR, 1.02 [95% CI, 1.01-1.03]; P=0.003), and LVOT gradient percent reduction <median (82%; HR, 2.92 [95% CI, 1.46-5.83]; P=0.002) were predictors of mortality. When adjusting for age and sex, baseline LA v wave >median (28 mm Hg; HR, 2.36 [95% CI, 1.17-4.76]; P=0.016), baseline mean LA pressure >median (19 mm Hg; HR, 2.70 [95% CI, 1.33-5.50]; P=0.006), percentage reduction in gradient <median (82%; HR, 2.74 [CI, 1.37-5.50]; P=0.005), and percentage increase in PP <median (19.3%; HR, 2.09 [CI, 1.05-4.16]; P=0.035) predicted survival free of all-cause mortality. ASA is associated with an acute decrease in the LVOT gradient and LA pressures and increase in aortic PP. Mean LA pressure, percentage decrease in LVOT gradient, and increase in PP are strong predictors of survival free of all-cause mortality following ASA and are important variables for procedural guidance.

Septal radioablation therapy for patients with hypertrophic obstructive cardiomyopathy: first-in-human study.

There is still no non-invasive septal reduction therapy for patients with hypertrophic obstructive cardiomyopathy (HOCM). This study aimed to investigate the feasibility, safety, and efficacy of stereotactic body radiotherapy (SBRT) in patients with drug-refractory symptomatic HOCM. The radiation target of ventricular septum was determined by multiple anatomical imaging. Stereotactic body radiotherapy was performed with standard techniques. Patients were treated with a single fraction of 25 Gy, followed up at 1, 3, 6, and 12 months by clinical visit. Five patients were enrolled and completed the 12 months follow-up. The mean radioablation time was 21.6 min, and the mean target volume was 10.5 cm3. All five patients survived and showed improvements in symptoms after SBRT. At 12 months post-SBRT, the echocardiography-derived left ventricular outflow tract gradient decreased from 88 mmHg (range, 63-105) to 52 mmHg (range, 36-66) at rest and from 101 mmHg (range, 72-121) to 74 mmHg (range, 65-100) after Valsalva. The end-diastolic thickness of the targeted septum reduced from 23.7 mm (range, 20.3-29) to 22.4 mm (range, 19.7-26.5); 6 min walking distance increased from 190.4 m (range, 50-370) to 412.0 m (range, 320-480). All patients presented with new fibrosis in the irradiated septum area. No radiation-related complications were observed during SBRT and up to 12 months post procedure. The current study suggests that SBRT might be a feasible radioablation therapeutic option for patients with drug-refractory symptomatic HOCM. ClinicalTrials.gov Identifier: NCT04686487.

Preoperative myocardial fibrosis is associated with worse survival after alcohol septal ablation in patients with hypertrophic obstructive cardiomyopathy: A delayed enhanced cardiac magnetic resonance study

BackgroundPrior studies have shown that myocardial fibrosis can be detected by late gadolinium enhancement (LGE) of cardiac magnetic resonance (CMR) and might be associated with higher mortality risk in hypertrophic cardiomyopathy (HCM). The objective of this study was to examine the prognostic utility of CMR in patients with hypertrophic obstructive cardiomyopathy (HOCM) undergoing alcohol septal ablation (ASA).Materials and methodsWe conducted a retrospective study which consisted of 183 consecutive patients with symptomatic drug-refractory HOCM who underwent CMR for assessment of myocardial fibrosis before ASA. The cardiovascular disease related survival was evaluated according to LGE-CMR status.ResultsThe cohort comprised 74 (40.4%) women with a mean age of 51 ± 8 years. Preoperative myocardial fibrosis was detected in 148 (80.9%) patients. After a median of 6 years (range 2–11 years) follow-up, adverse clinical events occurred in 14 (7.7%) patients. Multivariate-adjusted Cox regression analyses revealed that age [hazard ratio (HR) 1.142 (1.059–1.230), p = 0.001] and LGE [HR 1.170 (1.074–1.275), p < 0.001] were independent predictors of cardiovascular mortality during follow-up.ConclusionPreoperative myocardial fibrosis measured by LGE-CMR was an independent predictor of increased adverse clinical outcomes in patients with HOCM undergoing ASA and could be used for the pre-operative evaluation of risk stratification and long-term prognosis after ASA in these patients.

Real-world clinical outcomes of percutaneous transluminal septal myocardial ablation for patients with drug-refractory hypertrophic obstructive cardiomyopathy: results from a retrospective multicenter registry of non-high-volume centers.

Percutaneous transluminal septal myocardial ablation (PTSMA) is a well-established interventional therapy for drug-refractory hypertrophic obstructive cardiomyopathy (HOCM) as an alternative to surgical myectomy. Although guidelines recommend that PTSMA should be performed in institutions with extensive experience, it is not centralized to such high-volume centers in real-world clinical practice. Thus, this study aimed to assess the feasibility of PTSMA in non-high-volume centers. We retrospectively examined patients with HOCM who underwent PTSMA between August 2012 and May 2020 at four institutions that experienced fewer than 20 cases of PTSMA procedures. The primary clinical endpoint was a composite of safety (all-cause death, electrical defibrillation for ventricular tachycardia or fibrillation, cardiac tamponade, permanent pacemaker implantation, and repeated interventions) and efficacyendpoints (repeated interventions [PTSMA or surgical myectomy]). Fifty-eight consecutive patients were enrolled. During the 30-day follow-up, no major clinical adverse events were noted except three patients (5.2%) requiring permanent pacemaker implantation for complete atrioventricular block. The percentage of patients with New York Heart Association functional class 1 or 2 significantly increased from 8.6 to 100% (p < 0.001). In the Cox proportional hazard model, left ventricular outflow tract pressure gradient at rest ≥ 30mmHg (hazard ratio [HR] 6.56; 95% confidence interval [CI] 1.44-29.90; p = 0.015) and mitral regurgitation grade ≥ 3 (HR 10.75; 95% CI 1.81-63.79; p = 0.009) at the 30-day follow-up were associated with a composite of major clinical adverse events. The current study demonstrated that 58 patients who underwent PTSMA in non-high-volume centers had favorable 30-day clinical outcomes, with a primary composite endpoint rate of 5.2%. A prospective study with a larger sample size and longer follow-up is warranted to verify the safety and efficacy of PTSMA in non-high-volume centers.

Percutaneous Intramyocardial Septal Radiofrequency Ablation in Patients With Drug-Refractory Hypertrophic Obstructive Cardiomyopathy

Patients with hypertrophic obstructive cardiomyopathy (HOCM) and drug-refractory symptoms and outflow gradients have limited nonsurgical treatment options. The feasibility of percutaneous intramyocardial septal radiofrequency ablation (PIMSRA) has been reported previously; however, procedural and medium-term outcomes are unknown. To describe the safety and medium-term outcomes of PIMSRA in a large patient cohort with drug-refractory HOCM. This was a single-arm, open-label study of PIMSRA in patients with drug-refractory HOCM. Patients presenting to the Xijing Hospital in Xi'an, China, between October 2016 to June 2020 with hypertrophic cardiomyopathy. Of 1314 patients presenting with HOCM, 244 fulfilled inclusion criteria of severe resting/provoked outflow gradients of 50 mm Hg or higher, and symptoms of New York Heart Association functional class of II or higher refractory to maximum tolerated medications. After discussion among the heart team, 40 patients underwent surgical or alcohol septal reduction therapy and 4 required treatment of significant coronary artery disease. PIMSRA performed in patients. The primary outcome was 30-day major adverse clinical events: death, emergency surgery, severe effusion requiring intervention, procedure-related stroke, bleeding, and stroke. Secondary outcomes included 30-day technical success and 90-day improvement in outflow obstruction. The mean (SD) age of 200 patients was 46.9 (14.0) years, and 125 (62.5%) were men. Resting or provoked left ventricular outflow tract gradients were 50 mm Hg or higher. The median (IQR) follow-up for all patients was 19 (6-50) months. Thirty-day major adverse clinical events rate was 10.5% (n = 21): there were 2 in-hospital/30-day deaths (1.0%), 7 patients (3.5%) with pericardial effusion requiring mini-thoracotomy, 12 patients (6%) with pericardial effusion requiring pericardiocentesis, and no bleeding or strokes. Other periprocedural complications included permanent right bundle branch block in 5 patients (2.5%), resuscitated ventricular fibrillation in 2 (1.0%), and septal branch aneurysm in 2 (1.0%). There were no permanent pacemaker implantations. At follow-up, maximum septal thickness was reduced from a mean (SD) of 24.0 (5.1) mm to 17.3 (4.4) mm (P < .001), and left ventricular outflow tract gradient was decreased from a mean (SD) of 79.0 (53.0) mm Hg to 14.0 (24.0) mm Hg (P < .001). Overall, 190 patients (96%) with HOCM were in New York Heart Association functional class I or II at last follow-up. This study found that PIMSRA in patients with drug-refractory HOCM may be an effective procedure for relief of left ventricular outflow tract obstruction and symptoms with acceptable complication rates. These results are encouraging and support the design of a randomized clinical trial against well-established septal reduction therapies.

Hemodynamic change in patients with hypertrophic obstructive cardiomyopathy before and after alcohol septal ablation using 4D flow magnetic resonance imaging: a retrospective observational study

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Ministry of Education, Science, Sports and Culture of Japan, Grants-in-Aid for Scientific Research Background The hemodynamics in the left ventricle (LV) and the ascending aorta (AAO) before and after alcohol septal ablation (ASA) in patients with hypertrophic obstructive cardiomyopathy (HOCM) is elucidated. Purpose Our objective was to evaluate the pattern changes in AAO and intra-LV flow assessed by four-dimensional (4D) flow magnetic resonance imaging (MRI) before and after ASA and to clarify the association between 4D flow MRI-derived hemodynamic characteristics and the peak pressure gradient (PPG) in patients with drug-refractory HOCM. Methods In this retrospective observational study, 11 patients with HOCM underwent 4D flow MRI before and a week after ASA. The 4D flow MRI included blood flow visualization and quantification using streamline images. The combined score of vortex and helix in AAO was analyzed. The duration and phase count of the AAO vortex or helix flow [Figure 1a with vortex (yellow allow) before ASA and 1b without vortex after ASA] and the size of the intra-LV anterior vortex (Figure 1c with smaller vortex before ASA and 1d with larger vortex after ASA, both in white circle) were quantified. The correlation between the changes in hemodynamics and the resting PPG at LV outflow tract was also analyzed. We used the paired t-test for the comparison between before and after ASA and the Pearson"s correlation coefficient for the analysis. Results The combined score for the incidence of vortex and/or helix flow in AAO after ASA was significantly lower than that before ASA (1.45 ± 0.52 vs. 1.09 ± 0.30, p = 0.046). The duration (744 ± 291 ms vs. 467 ± 258 ms, p &amp;lt; 0.001) and phase count (14.8 ± 4.4 phases vs. 10.5 ± 5.8 phases, p &amp;lt; 0.001) of the vortex or helix flow in AAO were significantly decreased after ASA. The LV anterior vortex area after ASA was significantly larger than that before ASA (1628 ± 420 mm2 vs. 2974 ± 539 mm2, p = 0.009). The delta phase count of the AAO vortex or helix before and a week after ASA was significantly correlated with delta PPG before and a week after ASA (Figure 2a; R = 0.79, p = 0.004) and with delta PPG before and 6 months after ASA (Figure 2b; R = 0.83, p = 0.002). Conclusions Lower vortex or helix flow in AAO and larger diastolic vortex flow in LV were observed after ASA, which suggests the possibility to detect the changes of aberrant hemodynamics in HOCM. Abstract Figure. Streamline images before and after ASA

Combined ablation for paroxysmal atrial fibrillation and drug-refractory hypertrophic obstructive cardiomyopathy: a case report.

BackgroundHypertrophic obstructive cardiomyopathy (HOCM) is sometimes concomitant with atrial fibrillation (AF) and exacerbates heart failure symptoms. Although optimal medication for the reduction of left ventricular outflow tract (LVOT) obstruction and the maintenance of sinus rhythm should be considered, it is difficult to control the symptoms permanently.Case summaryA 45-year-old man, diagnosed with HOCM, presented with progressive dyspnoea on exertion, which significantly deteriorated during episodes of paroxysmal AF, despite optimal medical therapy. On echocardiography, we found LVOT obstruction with a peak pressure gradient of 98 mmHg, concomitant with redundant mitral valve leaflets, which caused significant systolic anterior motion (SAM). Since he declined open surgery, we selected a combination of catheter interventions, AF ablation, and alcohol septal ablation (ASA). After the AF ablation, the occurrence of AF significantly decreased, and there was no recurrence after the ASA. By 6 months, the plasma N-terminal pro-B-type natriuretic peptide level had decreased from 1022 to 124 pg/mL, the peak pressure gradient of LVOT decreased from 98 to 12 mmHg, and the left atrium volume decreased from 203 to 178.4 mL. The improvement in the SAM was visualized on echocardiography and was haemodynamically corroborated by the four-dimensional (4D)-flow cardiac magnetic resonance (CMR).DiscussionThe treatment of drug-refractory HOCM concomitant with paroxysmal AF needs both septal reduction and the maintenance of sinus rhythm, which can be accomplished through transcatheter interventions. Moreover, the detailed intra-ventricular haemodynamic assessment in HOCM patients can be explored using the 4D-flow CMR.

Effectiveness of alcohol septal ablation for hypertrophic obstructive cardiomyopathy in patients with late gadolinium enhancement on cardiac magnetic resonance

BackgroundAccording to European guidelines, alcohol septal ablation (ASA) for hypertrophic obstructive cardiomyopathy (HOCM) may be less effective in patients with extensive septal scarring on cardiac magnetic resonance (CMR). This study aimed to analyze the impact of late gadolinium enhancement (LGE) on CMR on the effectiveness of ASA. MethodWe conducted an observational retrospective study involving adult patients with symptomatic drug-refractory HOCM who underwent CMR before ASA at two European centres from May 2010 through June 2019. Patients were compared in binary format based on LGE presence. Moreover, a subanalysis focused on patients with septal fibrosis was performed. The effectiveness of ASA was evaluated by echocardiographic, ECG and clinical findings. ResultsOf the 113 study patients, 54 (48%) had LGE on CMR. The LGE quantification performed in 29 patients revealed septal fibrosis in 17. The mean follow-up was 4.4 ± 2.6 years. Baseline parameters were similar between groups except for basal septal thickness that was greater in LGE+ group (21.1 ± 3.9 mm for LGE+ vs. 19.2 ± 3.2 mm for LGE-: p = .005). ASA improved symptoms in all groups and reduced left ventricular outflow tract obstruction (LVOTO) (delta gradient reduction: LGE+: 62 ± 37.3%; septal LGE+: 75.6 ± 20.8%; LGE-: 72.5 ± 21.0%). However, 13% of the LGE+ and 2% of the LGE- group had residual LVOTO above 30 mmHg (p = .027). ConclusionASA was effective in all patients with HOCM, whether they had LGE on CMR or not and whether they had septal fibrosis or not.

Alcohol septal ablation: A useful tool in our arsenal against hypertrophic obstructive cardiomyopathy.

Affecting 1 in 500 individuals; hypertrophic cardiomyopathyis an autosomal dominant cardiovasculardisorder which is prevalent throughout the world. Surgical myectomy (SM) and alcohol septal ablation (ASA) are two methods currently used for the management of drug refractory hypertrophic obstructive cardiomyopathy (HOCM). ASA may prove to be a useful, less invasive treatment in patients with HOCM METHODS: Electronic literature search was conducted to identify articles that discussed methods to treat drug refractory HOCM. No limits were placed on timing of the publication or the type of article. Keywords and MeSH terms were used and the results were summarized in the relevant section. Current evidence suggests that alcohol septal ablation is a safe and effective procedure in treating patients with HOCM with similar short- and long-term outcomes when compared with SM. ASA has been shown to be a safe and reliable procedure; imaging techniques and dedicated multi-disciplinary teams can be used to select patients with HOCM. Though SM is recommended as gold standard treatment for drug refractory HOCM, ASA may play an increasing role in the near future due an ageing population; both ASA and SM can have a beneficial role in treating those who are affected by HOCM when the appropriate group of patients are selected for each intervention.

THE PLACE OF CARDIAC COMPUTED TOMOGRAPHY IN PREOPERATIVE PLANNING OF EXTENDED SEPTAL MYECTOMY IN PATIENTS WITH OBSTRUCTIVE FORM OF HYPERTROPHIC CARDIOMYOMATHY.

Hypertrophic cardiomyopathy (HCM) is the most common genetic cardiomyopathy. Extended septalmyectomy (ESM) is one of the priority methods of treatment of drug-refractory obstructive HCM. In recent years,hospital mortality during surgical correction of obstructive HCM in expert centers does not exceed 1-2 %. However,typical threatening complications of septal myectomy, such as iatrogenic ventricular septal defect (VSD) and rupture of the anterior or posterior walls of the left ventricle (LV), remain a topical issue in surgery of HCM. to show the role of preoperative CT-planning to predict and reduce possible technical problems associated with ESM, including iatrogenic VSD. This study includes 217 symptomatic patients with obstructive HCM, who from April 2016to October 2019 as one of the steps of preoperative planning underwent cardiac CT prior to ESM. Cardiac CT was performed to delineate the left ventricular myocardium, assess the distribution of hypertrophy and the presence ofcrypts. Special attention was also paid to the anatomy of the mitral valve (MV) and subvalvular apparatus. Coronaryartery patency was assessed by CAD-RADS, a standardized method for reporting the results of coronary CT angiography to determine tactics for further management of the patient. In the study group, the average age of patients was (49 ± 15) years, 48 % - men. All patientshad a symptomatic, drug-refractory obstructive form of HCM. The mean maximum wall thickness of the interventricular septum (IVS) was (20 ± 5) mm (range 16-33). The average LV mass was (118 ± 23) g/m2. 195 patients (89.9 %)had systolic anterior motion ( SAM) of the MV. MV and subvalvular apparatus anomalies were detected in 62 patients(28.6 %). A zone of scarring and regression of IVS after alcohol septal ablation (ASA) was detected in 7 patients(0.3 %) with residual LV outflow gradient. Coronary arteries atherosclerosis was detected in 32 patients (14.7 %). Preoperative CT-planning of septal myectomy allows to obtain information on morphology of the LV,IVS, MV and subvalvular apparatus, and gives the surgeon the advantage to form a more accurate plan for the location and volume of septal resection, and avoid complications when correcting obstructive HCM. No iatrogenic VSDwas detected in any of the patient in the study group.

Predictors of long-term outcome after septal myectomy in symptomatic hypertrophic obstructive cardiomyopathy patients with previous alcohol septal ablation and residual obstruction.

Recently alcohol septal ablation (ASA) has emerged as an alternative treatment for drug-refractory hypertrophic obstructive cardiomyopathy (HOCM) and a subgroup of HOCM patients with previous ASA may need myectomy. However, subsequent outcome and mechanism of residual obstruction has not been determined. This study aims to determine outcome after myectomy and mechanism of residual obstruction in HOCM patients with previous ASA. From February 2009 to June 2017, 38 HOCM patients with previous ASA underwent surgical septal myectomy at our institution. Seventy-six patients who underwent surgical septal myectomy initially were included as the comparison group through one-to-two propensity score matching method. Fourteen available cardiac magnetic resonance images revealed inferior location and small area of infarcted myocardium induced by ASA in 12 patients and outside targeted location in two patients. During follow-up (median, 2.4; maximum, 7.8 years), event-free survival at 7 years was 83.2% in the previous ASA group and 94.6% in the comparison group, respectively (P = 0.0378). Multivariable analysis indicated previous ASA (hazard ratio, 4.28; 95% confidence intervals [CI], 1.20-15.26; P = 0.025) and postoperative left ventricular end-diastolic diameter (hazard ratio, 1.14; 95% CI, 1.05-1.23; P = 0.002) were independent predictors of adverse events. This study demonstrated that uncontrollable extent and location of infarcted myocardium induced by ASA may attribute to residual obstruction after previous ASA, and the long-term event-free survival after myectomy was inferior. It may provide special precaution to patient selection and the increased number of ASA practiced worldwide.

Contemporary Septal Reduction Therapy in Drug-Refractory Hypertrophic Obstructive Cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) is a complex and relatively common genetic cardiac disease that has been the subject of intense investigation for over 50 years. Most patients with HCM are asymptomatic, but some develop symptoms, often many years after the appearance of electrocardiographic or echocardiographic evidence of left ventricular hypertrophy. Symptoms due to the left ventricular outflow tract obstruction frequently worsen over time, requiring septal reduction therapy (SRT) despite optimal medical therapy. Percutaneous transluminal septal myocardial ablation (PTSMA) and surgical myectomy are collectively known as SRT. In this review, we will focus on the emerging concept and practical implication of SRT and the available evidence on either PTSMA or surgical myectomy in the literature.

Clinical long-term outcome of septal myectomy for obstructive hypertrophic cardiomyopathy in infants.

Surgical septal myectomy is performed to relieve left ventricular outflow tract narrowing in severe drug-refractory obstructive hypertrophic cardiomyopathy. The objective of this study was to assess the perioperative and long-term clinical outcome of this procedure performed during infancy. Clinical, transthoracic echocardiographic, electrocardiographic, 24-h Holter, cardiopulmonary exercise test and genetic data were extracted by medical record review. A subset of patients underwent additional prospective detailed clinical evaluation including cardiac magnetic resonance imaging with contrast. Surgery was performed in 23 paediatric patients between 1978 and 2015 at the German Heart Centre Munich. Twelve patients had undergone surgery during infancy (≤ 1 year) (Group A), 11 between 1 and 18 years of age (Group B). The underlying genetic diagnosis was Noonan syndrome spectrum and non-syndromic hypertrophic cardiomyopathy. As compared to Group B, patients in Group A showed more concomitant cardiac procedures and received more homologous transfusions. One perioperative death occurred in Group A, and none in Group B. Two patients in Group A but no patient in Group B required redo septal myectomy. The long-term clinical outcome was similar between the 2 groups. One patient in Group B required cardioverter-defibrillator/pacemaker implantation for higher degree atrioventricular block and none in Group A. There was no evidence of differences in myocardial fibrosis between groups on long-term follow-up magnetic resonance imaging. Surgical septal myectomy can be performed safely during infancy with favourable perioperative and long-term clinical outcome but with a trend towards a higher reoperation rate later in life.

Chronic phase improvements in electrocardiographic and echocardiographic manifestations of left ventricular hypertrophy after alcohol septal ablation for drug-refractory hypertrophic obstructive cardiomyopathy.

After alcohol septal ablation (ASA), regression of left ventricular hypertrophy (LVH) has been observed in several studies using echocardiography or cardiac magnetic resonance, and favorable changes of myocardial excitation have been expected. However, no studies have focused on the alteration of electrocardiography (ECG) findings after ASA. Therefore, we evaluated serial changes in ECG parameters during the chronic phase after ASA for drug-refractory hypertrophic obstructive cardiomyopathy (HOCM). From 1998 to 2014, we performed 187 ASA procedures in 157 drug-refractory HOCM patients. After excluding patients who underwent dual-chamber pacing therapy and who underwent staged or repeat ASA within 2years after the index ASA, 25 patients without bundle branch block and additional pacemaker implantation were enrolled in the main study group. ECGs, echocardiograms, and clinical follow-up data were evaluated at baseline and, 1, 6, 12, and 24months after ASA. Patients with bundle branch block or additional pacemaker implantation were assigned in a referential group (n=79), in which the echocardiographic changes between baseline and at 1year were evaluated. Sokolow-Lyon index (SLi), Cornell index, and total 12-lead QRS amplitude significantly decreased during 2-year follow-up after ASA. SLi and Cornell index significantly decreased from 6 to 12months (p<0.05 vs. p<0.01). Changes in SLi were significantly associated with changes in the interventricular septal thickness (r=0.54, p<0.005), left ventricular mass index (r=0.40, p=0.050), and peak creatine phosphokinase level (r=-0.41, p=0.042), but not in the Cornell index and 12-lead QRS amplitude. In the comparison between baseline and at 1year, significant improvements in the interventricular septal thickness, posterior wall thickness, left atrial size, E/A ratio, and E/e' were observed in the echocardiographic study. Changes of SLi reflected regression of LVH after ASA with the best correlation. During the chronic phase after ASA, LVH regression was confirmed by echocardiographic and ECG parameters.

Ameliorating the severity of sleep-disordered breathing concomitant with heart failure status after percutaneous transluminal septal myocardial ablation for drug-refractory hypertrophic obstructive cardiomyopathy.

The coexistence of sleep-disordered breathing (SDB) and hypertrophic obstructive cardiomyopathy (HOCM) has widely been recognized; however, the impact of percutaneous transluminal septal myocardial ablation (PTSMA) for HOCM on SDB remains unknown. Herein, we examine cardiorespiratory polygraph parameters in patients with drug-refractory HOCM before and after PTSMA. Forty consecutive drug-refractory HOCM patients, admitted to Keio University Hospital, and who underwent cardiorespiratory polygraphy were retrospectively analyzed. Cardiorespiratory polygraphy was performed before and after PTSMA if patients underwent PTSMA. Patients with an apnea-hypopnea index (AHI) ≥5/h were considered to have SDB. The total number of central sleep apneas, obstructive sleep apneas, and hypopnea events was evaluated. Thirty-two out of 40 patients (80%) with drug-refractory HOCM had SDB. All patients experienced relief of heart failure-associated symptoms after PTSMA. The severity of SDB was found to be correlated with left atrial diameter. The AHI decreased after PTSMA [before 15.4 (range 10.9-23.5)/h vs. after 13.1 (8.3-17.8)/h, P=0.02]. Especially, the hypopnea index decreased after PTSMA. The average and lowest arterial oxygen saturation also increased after PTSMA (94.2±1.9-95.7±1.6%, P=0.009; 81.3±5.7-85.8±4.8%, P=0.012, respectively). In patients with drug-refractory HOCM, PTSMA decreased the AHI and improved arterial oxygen saturation measures. Thus, invasive treatment of the left ventricular obstruction ameliorates the severity of SDB, in addition to improving heart failure status.

TCTAP C-180 Utility of the Reverse Wire Technique in Alcohol Septal Ablation for Drug-refractory Hypertrophic Obstructive Cardiomyopathy

TCTAP C-180 Utility of the Reverse Wire Technique in Alcohol Septal Ablation for Drug-refractory Hypertrophic Obstructive Cardiomyopathy