Transcoronary ablation of septal hypertrophy for hypertrophic obstructive cardiomyopathy: feasibility, clinical benefit, and short term results in elderly patients

Alcohol septal ablation in patients aged 75 years or older with hypertrophic obstructive cardiomyopathy

OBJECTIVE

Outcome data for patients ≥75 years with hypertrophic obstructive cardiomyopathy (HOCM) undergoing alcohol septal ablation (ASA) are lacking. Therefore, a retrospective single-centre analysis was conducted.

METHODS

The data of all consecutive ASAs, that were performed at our institution between 1 September 1997 and 31 July 2021 in patients with HOCM with left ventricular outflow tract gradients (LVOTG) ≥50 mm Hg, were collected from patient reports. ASA was performed per institutional standards with 95% ethanol infused into a feasible septal branch. Differences regarding echocardiographic, procedural and clinical parameters at baseline and after 6 months between patients ≥75 years and <75 years were assessed.

RESULTS

We found 208 ASAs in patients ≥75 years (85.1% female; age 78.0 years (IQR 76.0-80.0)) and 1430 ASAs in patients <75 years (42.0% female; age 56.0 years (IQR 46.0-65.0)). Patients ≥75 years had lower distances in 6 min walk test (baseline: 317.0 m (IQR 242.0-389.0) vs 438.0 m (IQR 353.3-504.0); p<0.0001). Exercise-induced LVOTG calculated at follow-up was lower in patients ≥75 years (29.5 mm Hg (IQR 18.0-54.0) vs 39.5 mm Hg (IQR 23.0-73.8); p=0.0007). There were more high-degree AV blocks after ASA in patients ≥75 years (25.5% vs 13.6%; p<0.0001). The in-hospital mortality did not differ between the groups (age ≥75 years: 1.0%; age <75 years: 0.6%; p=0.6580).

CONCLUSION

ASA had similar efficacy and intrahospital mortality in patients ≥75 years compared with younger patients. Higher rates of AV block with need for permanent pacemaker implantation were observed in patients ≥75 years of age.

Hypertrophic Cardiomyopathy Diagnosed on Point-of-Care Echocardiogram in an Elderly Patient With Syncope

A bedside echocardiogram in the emergency department can provide a wealth of information about a patient’s hemodynamic status, anatomical structures, and response to medical interventions. This readily available tool can drastically guide management within minutes as soon as the undifferentiated critically ill patient enters the hospital. In this clinical scenario, we report a case of hypertrophic obstructive cardiomyopathy (HOCM) that was diagnosed for the first time in an elderly male, who was brought to the emergency department after a syncopal episode, utilizing bedside ultrasound and it highlights the significance of considering a broad differential.

Outcomes of Septal Myectomy beyond 65 Years, with and without Concomitant Procedures

Introduction and objectives: Septal myectomy remains the first septal reduction therapy for hypertrophic obstructive cardiomyopathy in young patients and those requiring concomitant procedures. Its role in advanced ages is questioned due to perceived increased risk. We assess the outcomes of surgical relief of obstruction in patients beyond 65 years old. Methods: A single-center retrospective review of patients ≥ 65 years old undergoing septal myectomy through median sternotomy between April 2015 and February 2020. Results: We identified 52 patients. Mean age was 71.8 ± 4.9 years; 36 (69.2%) were females. All were symptomatic. Mean highest LVOT gradient was 90 ± 39 mmHg. All patients had systolic anterior motion (SAM) of the mitral valve and 36 (69.2%) ≥ moderate mitral regurgitation. Additional LVOT interventions beyond myectomy were performed in 34 (65.4%). At least one other cardiac concomitant procedure was performed 44 (84.6%). No perioperative mortality in elective surgery occurred. One patient (1.9%) developed atrio-ventricular block. Postoperative mean gradient was 4.3 ± 1.9 mmHg, with 46 (88.4%) achieving complete resolution of obstruction. Mitral regurgitation was reduced to grade ≤ I in 46 (88.5%). Mean follow-up time was 2.3 ± 1.2 years and 82% of patients were in NYHA I. Survival at 2 years was 98%. Conclusion: Septal myectomy in the elderly is a safe and effective operation despite the need for concomitant procedures. LVOT interventions beyond septal myectomy to relieve obstruction are common in this advanced cohort of hypertrophic cardiomyopathy patients. This operation carried at experienced centers seems an unmatched therapeutic option.

Looking back on 15 years of ultrasound-guided alcohol septal ablation for hypertrophic obstructive cardiomyopathy

Background: Septal reduction remains an important target of current therapeutic modalities in hypertrophic obstructive cardiomyopathy (HOCM). Surgical septal myectomy has long been considered the gold standard in pharmacotherapy-refractory severely symptomatic patients with marked left ventricular outflow tract (LVOT) obstruction. In recent years, percutaneous alcohol septal ablation (ASA) has matured into the preferred strategy for patients with favourable anatomy and no other coexisting surgically amenable disease.Methods: We discuss 26 HOCM patients with persistent dyspnoea, angina or syncope despite optimal medical treatment. Baseline septal wall thickness was 20 ± 3 mm, with peak resting/provoked LVOT gradients of 53 ± 35/112 ± 40 mmHg. Guided by echocardiography, alcohol injection could be restricted to the first septal coronary artery in 85% of patients, provoking basal septal infarction with average troponin rise of 3.0 ng/ml.Results: Eighty-six per cent of patients experienced sustained clinical improvement, associated with a reduction of septal wall thickness to 15 ± 3 mm and resting LVOT gradient to 21 ± 15 mmHg. One of the two non-responders underwent additional septal myectomy 11 years after ASA. Notable adverse events during the follow-up of 7.2 ± 4.7 years included: persistent conduction disturbances (65%) necessitating early postprocedural permanent pacemaker implantation (15%); atrial fibrillation (32%); ventricular tachycardia (4%) and aortic stenosis (14%). Six patients died, of which only 1 cardiac death.Conclusions: Our case series underscores the efficacy of ASA at relieving LVOT obstruction and improving symptoms in properly selected HOCM patients, with acceptably low procedural and long term mortality and morbidity.

Short- and long-term outcome after alcohol septal ablation in obstructive hypertrophic cardiomyopathy: Experience of a reference center

INTRODUCTION

In obstructive hypertrophic cardiomyopathy (HCM), alcohol septal ablation (ASA) can lead to gradient reduction and symptom improvement. We aimed to assess the efficacy and safety of ASA in a long-term outcome study.

METHODS

We analyzed patients who underwent ASA over a seven-year period in a tertiary center. The primary echocardiographic endpoint was >50% reduction in left ventricular outflow tract (LVOT) gradient within a year of the procedure. The primary clinical endpoints were improvement in functional capacity and a combined endpoint of cardiac death and rehospitalization for cardiac cause. The follow-up period was 4.17±2.13 years.

RESULTS

A total of 80 patients, mean age 63.9±12.3 years, 30.0% male, were analyzed. Baseline LVOT gradient was 96.3±34.6 mmHg and interventricular septal thickness was 21.6±3.1 mm. Minor complications were observed in 6.3% and major complications in 2.5%, and 8.8% received a permanent pacemaker. The primary echocardiographic endpoint was achieved by 85.7%. At three-month follow-up, LVOT gradient was 25.8±26.0 mmHg in the successful procedure group, compared to 69.2±35.6 mmHg in the other patients (p=0.001). At six months, LVOT gradient was 27.1±27.4 vs. 58.2±16.6 mmHg (p=0.024). Among 74 patients in NYHA class III/IV before the procedure, 57 (77%) improved to NHYA class I/II. The combined primary clinical endpoint (cardiac death and rehospitalization for cardiac cause) was observed in 27.5% (n=22). In the unsuccessful group, the combined endpoint was observed in 54.5%, compared to only 22.7% in the successful group. Only two patients died of cardiac causes.

CONCLUSION

ASA is a safe procedure with a high success rate. Patients who achieved significant reductions in LVOT gradient suffered less cardiac death and rehospitalization for cardiac cause.

Efficacy and safety of alcohol septal ablation in patients over 65 years old with obstructive hypertrophic cardiomyopathy

Background

The performance of alcohol septal ablation (ASA) in elderly symptomatic patients with drug-refractory obstructive hypertrophic cardiomyopathy is still to be confirmed. The objective of this study was to compare the efficacy and safety of ASA in patients under and over 65 years old.

Methods and results

Fifty-one consecutive patients with obstructive hypertrophic cardio-myopathy who underwent ASA were retrospectively included and reviewed for in-hospital major acute cardiac events and follow-up. Twenty-eight patients were over 65 years old. Left ventricular outflow tract obstruction at rest, use of diuretic and average dose of diuretic were higher in patients over 65 years old. There was no difference in hospital stay between patients under and over 65 years old. Among patients over 65 years old, 2 (7%) died before being discharged. Major acute cardiac events were more frequent in patients over 65 years old in comparison with younger patients (43% versus 9%, respectively, P=0.007). The average follow-up duration was 16±15 months. There was no difference between patients under and over 65 years old regarding the efficacy of the procedure with a decrease of the New York Heart Association class of 1.3±0.6 and 1.4±0.7 (P=0.510) and the maximum left ventricular outflow tract gradient of 86±57 and 81±36 mmHg (P=0.733), respectively.

Conclusion

Elderly patients have the same benefits as younger patients after ASA but have more complications including mortality events.

Alcohol septal ablation for obstructive hypertrophic cardiomyopathy: outcomes in young, middle-aged, and elderly patients

OBJECTIVES

We compared the efficacy and safety of alcohol septal ablation (ASA) for obstructive hypertrophic cardiomyopathy (HCM) in young, middle-aged, and elderly patients.

BACKGROUND

Intersociety guidelines suggest based on limited evidence that young patients with medically refractory symptoms of obstructive HCM should undergo surgical myectomy while elderly patients may be more appropriate for ASA.

METHODS

Data for 360 patients undergoing 389 ASAs were prospectively collected and retrospectively analyzed according to age.

RESULTS

Young (<45 years), middle-aged (45-64 years), and elderly (≥65 years) patients comprised 28, 40, and 32% of the study population, respectively. Young patients had thicker left ventricular septal walls at baseline, and elderly patients had more comorbidity and dyspnea. Resting, mean left ventricular outflow tract gradients (LVOTGs) were similar across the age groups at baseline (62, 66, and 68 mm Hg, respectively; P = NS for all comparisons). LVOTGs and dyspnea were significantly and similarly improved in all age groups immediately after ASA and through 12 months of follow-up (P < 0.001 for before and after comparisons; P = NS for intergroup comparisons). Complication rates were similar for young and middle-aged patients but higher for elderly patients (9.1 and 6.3% vs. 20.8%, respectively; P ≤ 0.016 for elderly vs. others). Mortality rates for young and middle-aged patients were lower than for elderly patients, but the differences were not statistically significant.

CONCLUSIONS

Patients undergoing ASA had significant and similar improvements in LVOTGs and symptoms regardless of age. Procedural complications were increased in elderly patients, who had numerically but not statistically significantly higher mortality rates.

Long-term outcome of percutaneous transluminal septal myocardial ablation in hypertrophic obstructive cardiomyopathy: a Scandinavian multicenter study

BACKGROUND

Single-center reports on percutaneous transluminal septal myocardial ablation (PTSMA) in patients with hypertrophic obstructive cardiomyopathy have shown considerable differences in outcome.

METHODS AND RESULTS

We report the long-term outcome of 313 PTSMA procedures performed in 279 patients with hypertrophic obstructive cardiomyopathy aged 59±14 years from 1999 to 2010 in 4 Scandinavian centers. Sixty-nine percent of patients had ≥1 comorbidity at baseline. The median (interquartile range) of left ventricular outflow tract gradient at rest was reduced from 58 mm Hg (34 to 89 mm Hg) at baseline to 12 mm Hg (8 to 24 mm Hg) at 1-year (P<0.001) and during Valsalva maneuver from 93 mm Hg (70 to 140 mm Hg) to 21 mm Hg (11 to 42 mm Hg) (P<0.001). The proportion of patients with syncope was reduced from 18% to 2% (P<0.001), and the proportion in New York Heart Association class III/IV was reduced from 94% to 21% (P<0.001). All treatment effects remained stable during the follow-up. New York Heart Association class III/IV at the most recent follow-up (2.9±2.6 years) was associated with diabetes mellitus (P=0.03), chronic obstructive pulmonary disease (P=0.02), and valve disease unrelated to hypertrophic cardiomyopathy (P<0.01). In-hospital mortality was 0.3%. The 1-, 5- and 10-year survival rates were 97%, 87%, and 67%, respectively (P=0.06 versus an age- and sex-matched background population) in all patients and 99%, 94%, and 88%, respectively (P=0.12) in patients aged <60 years (48±9 years, n=141). Age (hazard ratio, 1.07; 95% CI, 1.03 to 1.1) was the only predictor of survival.

CONCLUSIONS

In this multicenter study, the in-hospital mortality after PTSMA was low despite considerable comorbidities. The hemodynamic and symptomatic effects were sustained long term. The long-term symptomatic outcome was associated with baseline comorbidities. The 10-year survival rate was comparable to that in an age- and sex-matched background population, and age was the only predictor of survival.

The diagnosis and treatment of hypertrophic cardiomyopathy

BACKGROUND

Hypertrophic cardiomyopathy (HCM) is the most common hereditary disease of the heart.

METHODS

In this article, we summarize the current state of the diagnosis and treatment of HCM on the basis of a selective review of recent publications with relevance to clinical practice.

RESULTS

Several hundred mutations in more than 27 genes, most of which encode sarcomeric structures, are associated with the HCM phenotype. Thus, HCM can be thought of as a sarcomeric disease, with myocardial fiber disarray as its histological hallmark. There are two types of HCM, a more common, obstructive type (HOCM, 70%) and a less common, non-obstructive type (HNCM; in all cases of HCM, testing should be performed to detect outflow obstruction at rest and/or on provocation, and to thereby determine whether HOCM or HNCM is present. The symptoms of HCM include dyspnea, angina pectoris, palpitations, dizziness, and occasionally syncope. Because sudden cardiac death is the most serious complication of HCM, particularly in young and asymptomatic patients, it follows that correct diagnosis, followed by risk stratification of patients with regard to the need for prophylactic implantation of an implantable cardiac defibrillator (ICD), can be of life-saving importance. The pharmacotherapy of symptomatic HNCM consists of the treatment of heart failure with a normal ejection fraction (HFNEF). In HOCM, the patient's symptoms and the obstructive gradient are the guide to treatment with beta-blockers or verapamil. For patients with drug-resistant disease, surgical myectomy and percutaneous septal ablation are now standard treatments.

CONCLUSION

A near-normal life expectancy and a highly satisfactory quality of life are now realistic treatment goals for patients with HCM.

Controversies in cardiovascular medicine. Hypertrophic obstructive cardiomyopathy: alcohol septal ablation

Alcohol septal ablation (ASA) was introduced in 1994 as an alternative to septal myectomy for patients with hypertrophic obstructive cardiomyopathy and symptoms refractory to medical therapy. This procedure alleviates symptoms by producing a targeted, limited infarction of the upper interventricular septum, resulting in an increase in left ventricular outflow tract (LVOT) diameter, a decrease in LVOT gradient, and regression of the component of LV hypertrophy that is due to pressure overload. Clinical success, with improvement in symptoms and reduction in gradient, is achieved in the great majority of patients with either resting or provocable LVOT obstruction. The principal morbidity of the procedure is complete heart block, resulting in some patients in the requirement for a permanent pacemaker. The introduction of myocardial contrast echocardiography as a component of the ASA procedure has contributed to the induction of smaller myocardial infarctions with lower dosages of alcohol and, in turn, fewer complications. Non-randomized comparisons of septal ablation and septal myectomy have shown similar mortality rates and post-procedure New York Heart Association class for the two procedures.

Differential protein expression in heart in UT-B null mice with cardiac conduction defects

Cardiac conduction defects were found in transgenic mice deficient in urea transporter UT-B. To investigate the molecular mechanisms of the conduction defects caused by UT-B deletion, we studied the protein expression profiles of heart tissue (comprising most conduction system) in wild-type versus UT-B null mice at different ages. By two-dimensional electrophoresis-based comparative analysis, we found that more than dozen proteins were modulated (>two-fold) in the myocardium of UT-B null mice. Out of these modulated proteins, troponin T (TNNT2) presented significant changes in UT-B null mice at early stage prior to the development of P-R interval elongation, while the change of atrial natriuretic peptide (ANP) occurred only at late stage in UT-B null mice that had the AV block. These data indicate that UT-B deletion caused the dynamic expression regulation of TNNT2 and ANP, and these proteins may provide new clues to investigate the molecular events involved in cardiac conduction.

Alcohol septal ablation for hypertrophic obstructive cardiomyopathy: a systematic review of published studies

OBJECTIVE

Alcohol septal ablation (ASA) for hypertrophic obstructive cardiomyopathy (HOCM) has emerged as a lesser invasive alternative to surgical myectomy over the past decade. The purpose of this study is to analyze all the published literature on outcomes and complications after ASA.

METHODS

MEDLINE and PubMed were searched for all available published literature on ASA (June 1996-June 2005) using the terms hypertrophic obstructive cardiomyopathy (HOCM), alcohol septal ablation for hypertrophic obstructive cardiomyopathy, alcohol septal ablation for HOCM, alcohol septal ablation (ASA), transcoronary alcohol septal ablation for hypertrophic obstructive cardiomyopathy (TASH), transcoronary alcohol septal ablation for HOCM, nonsurgical septal reduction therapy (NSRT), and percutaneous transcoronary septal myocardial ablation (PTSMA).

RESULTS

A total of 42 published studies (2,959 patients) were analyzed. Mean age was 53.5 (35.4-72) years with a mean male to female ratio of 1.17. Mean follow-up was 12.7 +/- 0.3 months (1.5-43.2). Absolute ethanol (3 mL) was injected in 1.2 septal perforator arteries. On average, serum CK peaked at 964 units. At 12 months, there was a sustained decrease in resting and provoked LVOT gradient (65.3-15.8 and 125.4-31.5 mmHg, respectively) accompanied by reduction in basal septal diameter (20.9-13.9 mm), improvement in NYHA Class (2.9-1.2), and increase in exercise capacity (325.3-437.5 seconds). Early mortality (within 30 days) was 1.5% (0.0-5.0%) and late mortality (beyond 30 days) was 0.5% (0.0-9.3%). Other complications include ventricular fibrillation (2.2%), LAD dissection (1.8%), complete heart block requiring permanent pacemaker (10.5%), and pericardial effusion (0.6%). A repeat ASA was performed on 6.6% of patients and 1.9% of patients underwent surgical myomectomy with resolution of symptoms.

CONCLUSIONS

Literature to date suggests that ASA results in acute and intermediate-term favorable clinical and echocardiographic outcomes. A randomized controlled trial is needed to compare ASA and myomectomy in order to determine which technique provides maximal benefit.

Time course of pressure gradient response after first alcohol septal ablation for obstructive hypertrophic cardiomyopathy

Alcohol septal ablation (ASA) causes remodeling of the upper septum and left ventricular outflow tract (LVOT) and reduction in the LVOT gradient. The time course of gradient reduction early after ASA has not been established. This study characterized the time course of gradient response early after ASA. Patients underwent clinical assessment and transthoracic echocardiography at baseline and immediately, 3 days, 3 months, and 1 year after ASA. Forty-seven patients underwent ASA. The baseline LVOT gradient was 98 +/- 48 mm Hg. Three-month echocardiographic success, defined as > or = 50% gradient reduction from baseline, was achieved in 41 procedures (87%); thus, there were 6 failures. On the basis of percentage reduction in LVOT gradient at 3 days, 2 distinct subgroups of the success group were identified. These were monophasic success (> or = 50% gradient reduction at 3 days and 3 months, n = 25) and triphasic success (< 50% gradient reduction at 3 days but > or = 50% gradient reduction at 3 months, n = 16). LVOT gradient in the triphasic success group was similar to that in the failure group at 3 days (81 +/- 28 vs 99 +/- 31 mm Hg, p = NS) but similar to that of the monophasic success group at 3 months (24 +/- 20 vs 12 +/- 16 mm Hg, p = NS) and at 1 year (27 +/- 24 vs 13 +/- 20 mm Hg, p = NS). In conclusion, many patients who undergo ultimately successful ASA demonstrate triphasic LVOT gradient response patterns, with a large gradient 3 days after the procedure.

Focalized Contractile Impairment at Hypertrophied Myocardium Proven in Consideration of Wall Stress in Patients With Hypertrophic Cardiomyopathy

In hypertrophic cardiomyopathy (HCM) a hyperkinetic state is sometimes observed in spite of impaired systolic function in the hypertrophied myocardium. The aim of the present study was to determine the mechanism of this paradox. Seventeen patients with HCM and 10 normal subjects underwent cine magnetic resonance (MR) imaging to measure percent systolic wall thickening and percent fractional shortening. The ratio of systolic radial wall stress of the LV at the hypertrophied myocardium over that at the nonhypertrophied myocardium was evaluated to describe the focal advantageous condition for wall thickening. The ratio was 0.66 +/- 0.36 at the start of contraction and 0.78 +/- 0.31 at early-systole, indicating consistently smaller radial wall stress at the hypertrophied myocardium. Although the condition for contraction was favorable (a ratio less than 1.00), percent systolic wall thickening at the hypertrophied myocardium (23.0 +/- 11.8%) was smaller than that at the nonhypertrophied myocardium (70.5 +/- 32.3%). Smaller end-diastolic dimension (HCM group; 45.2 +/- 4.2 mm, reference group; 48.9 +/- 4.1 mm, P = 0.04) with a statistically identical value of systolic decrease in intraventricular dimension (HCM group; 19.7 +/- 3.9 mm, reference group; 18.9 +/- 3.2 mm, P = 0.60) yielded high percent fractional shortening in patients with HCM (43.5 +/- 7.6%). Although contractile impairment was proven at the hypertrophied region with low radial wall stress in the HCM group, the smaller end-diastolic dimension in this group resulted in high percent fractional shortening.

Age-Related Hemodynamic and Morphologic Differences in Patients Undergoing Alcohol Septal Ablation for Hypertrophic Obstructive Cardiomyopathy

BACKGROUND

Alcohol septal ablation (ASA) decreases the left ventricular (LV) outflow gradient and relieves symptoms in patients with highly symptomatic hypertrophic obstructive cardiomyopathy (HOCM). The aim of this study was to evaluate the early course of hemodynamic, morphologic and clinical changes in younger and elderly patients.

METHODS AND RESULTS

Forty-four consecutive patients (age, 24-81 years) underwent the ASA procedure for HOCM. Clinical and echocardiographic data were obtained at baseline and periodically up to 12 months after ASA. There was a significant correlation between septum thickness and age at baseline and in the early post procedural period (p = 0.004 at baseline, p = 0.0033 days postoperative, p = 0.0193 weeks pos operative). The dependence of septal thickness on the duration of follow-up (p < 0.001) was significantly influenced by age (p = 0.026), which retained statistical significance after multivariate adjustment (p = 0.031). A decrease in the gradient of the LV outflow was identified in all age-related groups of patients (p < 0.001). After multivariate adjustment, there was a significant influence of age (p = 0.003) and creatine kinase-MB peak (p = 0.016) on the course of outflow gradient reduction.

CONCLUSIONS

ASA is an effective treatment option for patients with HOCM, irrespective of their age. Younger patients are characterized by a thicker basal septum at baseline and a slower hemodynamic improvement within the early post procedural period.