Clinical practice and prospects of septal myectomy in the treatment of hypertrophic cardiomyopathy

A industria brasileira, apos intenso processo de crescimento e consolidacao durante seu periodo de industrializacao substitutiva de importacoes (1956-1979), passou a sofrer, dentro de um contexto de mudanca de paradigma produtivo, um constante processo de defasagem quanto a incorporacao de tecnologias a partir dos anos 80. Esse atraso se manifestou tanto na obsolescencia das maquinas e equipamentos, quanto nos modelos administrativos e nas relacoes capital-trabalho, devido principalmente ao Estado, principal fomentador do desenvolvimento da economia e da industria ter perdido a capacidade de realizar politicas industriais (PI) e tecnologicas (PT) que promovessem uma rearticulacao interna das forcas produtivas. Nesse sentido, na presente pesquisa se concentrou a discussao na apresentacao dos determinantes fundamentais do atraso tecnologico da industria brasileira decisivamente a partir dos anos 80, analisando-se, para isso, as condicionantes politicas, economicas e ideologicas, tendo-se como foco as politicas industriais e tecnologicas promovidas pelo Estado brasileiro que, mesmo fomentando um crescimento industrial acelerado da economia com base no paradigma da producao em massa, basicamente prezou pelo desenvolvimento de uma industria voltada para a capacidade produtiva. Nesse sentido, quando se tornou premente uma transicao para o novo paradigma de producao flexivel, esta embasada na geracao de capacidade tecnologica, emergiram inumeras barreiras a essa mudanca. Mesmo a economia tendo buscado desenvolver um nucleo de pesquisa e desenvolvimento e ciencia e tecnologia proprios, esses nao foram suficientemente dinâmicos o bastante a ponto de colocar o pais em movimentos de catching up tecnologico constante como ocorria nos paises mais desenvolvidos, buscando-se direcionar o desenvolvimento da economia para o novo paradigma produtivo. De outro lado, quanto as PI e PT adotadas no desenvolvimento da Coreia do Sul, o fomento do processo de catching up produtivo e tecnologico possibilitou a esse pais absorver de forma dinâmica a “janela de oportunidade” que se abriu com o surgimento do novo paradigma, possibilitando ao pais, que teve um processo de industrializacao tardia como o Brasil, desenvolvesse uma das principais industrias do mundo no que tange a geracao de produtos intensivos em alta tecnologia, votados ao mercado internacional, levando a economia coreana a se situar proximo ou sobre a fronteira tecnologica em expansao do novo paradigma. Assim, o estudo parte do referencial teorico da abordagem schumpeteriana a fim apontar alguns dos elementos que levaram a estrutura industrial brasileira a se conformar com um dinamismo relativamente lento no seu processo de desenvolvimento tecnologico formando uma estrutura com pouca competitividade nos setores mais dinâmicos da industria, os de alta tecnologia e que representam, atualmente o segmento chave da competicao empresarial internacional. Este cenario contrasta com o caso oposto da Coreia do Sul onde esse setor da economia, atualmente, se mostra bastante dinâmico em termos de geracao e disseminacao das inovacoes tecnologicas.

2011;58;2703-2738; originally published online Nov 8, 2011; J. Am. Coll. Cardiol. W. Yancy Rakowski, Christine E. Seidman, Jeffrey A. Towbin, James E. Udelson, and Clyde Fifer, Mark S. Link, Srihari S. Naidu, Rick A. Nishimura, Steve R. Ommen, Harry Bernard J. Gersh, Barry J. Maron, Robert O. Bonow, Joseph A. Dearani, Michael A. Thoracic Surgeons Society for Cardiovascular Angiography and Interventions, and Society of Nuclear Cardiology, Heart Failure Society of America, Heart Rhythm Society, of Thoracic Surgery, American Society of Echocardiography, American Society Developed in Collaboration With the American Association for Guidelines Cardiology Foundation/American Heart Association Task Force on Practice Cardiomyopathy: Executive Summary: A Report of the American College of 2011 ACCF/AHA Guideline for the Diagnosis and Treatment of Hypertrophic This information is current as of May 14, 2012 http://content.onlinejacc.org/cgi/content/full/58/25/2703 located on the World Wide Web at: The online version of this article, along with updated information and services, is

Hypertrophic cardiomyopathy is a relatively recent concept. It occurs not infrequently; ≈1 in 500 individuals within the general population is a carrier of the disease.1 The main genes responsible for hypertrophic cardiomyopathy have been characterized and can be determined with relative ease.2 Some patients develop subaortic obstruction. The original term, idiopathic hypertrophic subaortic stenosis, dates to 1964;3 since then, it has become obvious that the obstructive component has its own prognostic meaning. The obstruction occurs in ≈25% of all humans with hypertrophic cardiomyopathy,4 and the entity is now called hypertrophic obstructive cardiomyopathy. Article p 131 Surgery for elimination of the obstructive element via resection of the subaortic septal bulge (myectomy) has been, since its introduction by Cleland at the Brompton in London exactly half a century ago, the only rational option for patients with clinically relevant left ventricular outflow tract obstruction that is refractory to optimal medical therapy. At experienced centers, the operation can be performed with low mortality and excellent clinical improvement.5 The concept of using transluminal techniques to reduce septal hypertrophy in patients with hypertrophic obstructive cardiomyopathy was not based on the hope of achieving better results than with surgery, but primarily to reduce morbidity. In the early 1980s, while performing coronary angiography on patients with hypertrophic obstructive cardiomyopathy, I noticed that in some patients, the first septal perforator branches appeared to irrigate primarily the area of the septal bulge responsible for outflow tract obstruction. During systole, these branches seemed to be compressed by the surrounding hyperabundant myocardium. Interfering with the proper irrigation of this …

Septal myectomy in context: Clinical acumen and procedural expertise

Hypertrophic Cardiomyopathy in Elderly Individuals: Is It a Rose by Another Name?

Septal Reduction Therapy for Obstructive Hypertrophic Cardiomyopathy: Volume Still Matters for Septal Myectomy

Hypertrophic cardiomyopathy (HCM) is an inherited disease of the heart muscle characterized by otherwise unexplained thickening of the left ventricle. Left ventricular outflow tract (LVOT) obstruction is present in approximately two-thirds of patients and substantially increases the risk of disease complications. Invasive treatment with septal myectomy or alcohol septal ablation can improve symptoms and functional status, but currently available drugs for reducing obstruction have pleiotropic effects and variable therapeutic responses. New medical treatments with more targeted pharmacology are needed, but the lack of preclinical animal models for HCM with LVOT obstruction has limited their development. HCM is a common cause of heart failure in cats, and a subset exhibit systolic anterior motion of the mitral valve leading to LVOT obstruction. MYK-461 is a recently-described, mechanistically novel small molecule that acts at the sarcomere to specifically inhibit contractility that has been proposed as a treatment for HCM. Here, we use MYK-461 to test whether direct reduction in contractility is sufficient to relieve LVOT obstruction in feline HCM. We evaluated mixed-breed cats in a research colony derived from a Maine Coon/mixed-breed founder with naturally-occurring HCM. By echocardiography, we identified five cats that developed systolic anterior motion of the mitral valve and LVOT obstruction both at rest and under anesthesia when provoked with an adrenergic agonist. An IV MYK-461 infusion and echocardiography protocol was developed to serially assess contractility and LVOT gradient at multiple MYK-461 concentrations. Treatment with MYK-461 reduced contractility, eliminated systolic anterior motion of the mitral valve and relieved LVOT pressure gradients in an exposure-dependent manner. Our findings provide proof of principle that acute reduction in contractility with MYK-461 is sufficient to relieve LVOT obstruction. Further, these studies suggest that feline HCM will be a valuable translational model for the study of disease pathology, particularly LVOT obstruction.

About 80-90% of patients with Noonan syndrome have changes in the cardiovascular system, 30% of which include cardiomyopathy, hypertrophic phenotype in particular. The treatment of cardiomyopathy patients with Noonan syndrome is carried out according to the clinical recommendations for the treatment of chronic heart failure (CHF) and cardiomyopathy. Surgical treatment of progressive nature of heart failure with left ventricular outflow tract obstruction and mitral regurgitation can be one of the possible methods. The review presents our experience with septal myectomy (SM) in children suffered from hypertrophic obstructive cardiomyopathy with Noonan syndrome. Objective. To assess the efficiency of septal myectomy in children suffered from hypertrophic obstructive cardiomyopathy with Noonan syndrome. Materials and methods. Clinical examination (family history, patient examination), lab tests (NT-proBNP level), echocardiography, electrocardiography, Holter monitoring, Chest X-rays and molecular genetic methods using mass parallel sequencing (NGS) and direct automatic Sanger sequencing. The indications for the SM were determined according to the clinical guidelines for the diagnostic and treatment of hypertrophic cardiomyopathy. Results. 7 patients out of 48 with Noonan syndrome underwent SM and 1 with Noonan syndrome with multiple lentigo (LEOPARD). Two of them required the removal of obstruction of the outflow tracts of both ventricles, followed by plastic removal of the right ventricle and pulmonary artery valve. Related surgical interventions included aortic (n = 1) and mitral valves (n = 2), permanent pacemaker (n = 1) in the early postoperative period. After a year, all children recorded a decline of NT-proBNP from the average of 16,198 to 3,865 pg/ml, a significant improvement in health, disappearance of shortness of breath, increased physical activity tolerance, improved physical (weight, growth) and speech development. When assessing the dynamics of the Echo parameters 1 year after the SM, normalization of the size of both atria in 4 cases, reduction of severity of isolated dilation of the left atrium in 2 cases was noted. No cases of repeated obstruction have been reported. Conclusion. Hypertrophic cardiomyopathy (HCM) can be in structure of hereditary syndromes such as Noonan syndrome. Septal myectomy (SM) can now be used in the case of progressive nature of heart failure with left ventricular outflow tract obstruction in children with Noonan syndrome.

Previous data on septal myectomy (SM) and alcohol septal ablation (ASA) in obstructive hypertrophic cardiomyopathy have been limited to small, nonrandomized, single-center studies. Use of septal reduction therapy and the effect of institutional experience on procedural outcomes nationally are unknown. To examine in-hospital outcomes after SM and ASA stratified by hospital volume within a large, national inpatient database. This study analyzed all patients who were hospitalized for SM or ASA in a nationwide inpatient database from January 1, 2003, through December 31, 2011. Rates of adverse in-hospital events (death, stroke, bleeding, acute renal failure, and need for permanent pacemaker) were examined. Multivariate logistic regression analysis was performed to compare overall outcomes after each procedure based on tertiles of hospital volume of SM and ASA. Of 71 888 761 discharge records reviewed, a total of 11 248 patients underwent septal reduction procedures, of whom 6386 (56.8%) underwent SM and 4862 (43.2%) underwent ASA. A total of 59.9% of institutions performed 10 SM procedures or fewer, whereas 66.9% of institutions performed 10 ASA procedures or fewer during the study period. Incidence of in-hospital death (15.6%, 9.6%, and 3.8%; P < .001), need for permanent pacemaker (10.0%, 13.8%, and 8.9%; P < .001), and bleeding complications (3.3%, 3.8%, and 1.7%; P < .001) after SM was lower in higher-volume centers when stratified by first, second, and third tertiles of hospital volume, respectively. Similarly, there was a lower incidence of death (2.3%, 0.8%, and 0.6%; P = .02) and acute renal failure (6.2%, 7.6%, and 2.4%; P < .001) after ASA in higher-volume centers. The lowest tertile of SM volume among hospitals was an independent predictor of in-hospital all-cause mortality (adjusted odds ratio, 3.11; 95% CI, 1.98-4.89) and bleeding (adjusted odds ratio, 3.77; 95% CI, 2.12-6.70), whereas being in the lowest tertile of ASA by volume was not independently associated with an increased risk of adverse postprocedural events. In US hospitals from 2003 through 2011, most centers that provide septal reduction therapy performed few SM and ASA procedures, which is below the threshold recommended by the 2011 American College of Cardiology Foundation/American Heart Association Task Force Guideline for the Diagnosis and Treatment of Hypertrophic Cardiomyopathy. Low SM volume was associated with worse outcomes, including higher mortality, longer length of stay, and higher costs. More efforts are needed to encourage referral of patients to centers of excellence for septal reduction therapy.

New ESC guidelines on hypertrophic cardiomyopathy: new insights in invasive treatment?

Invasive therapies for symptomatic obstructive hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) – is the most common genetically determined heart disease, characterized by symmetrical or asymmetrical myocardial thickening (≥15 mm), leading to progressive heart failure and a high risk of sudden cardiac death (SCD). Diagnosis, natural course and treatment of HCM have become sources of uncertainty, misunderstanding and debate due to the increasing complexity of diagnosis in clinical practice, international differences in strategic approaches, advances in the treatment of genetic diseases and cardiac imaging. The aim. To amplify the current concept of HCM pathogenesis and mechanisms of the left ventricular outflow tract (LVOT) obstruction as well as to highlight our own results of HCM surgical correction. Materials and methods. A total of 330 HCM patients underwent surgical correction (septal myectomy) in the National M. Amosov Institute of Cardiovascular Surgery affiliated to National Academy of Medical Sciences of Ukraine. The mean age of the patients was 49.7 ± 15.0 years, median – 53; 168 (50.9 %) were male. Results. Surgical correction of HCM significantly improves the quality of life (80 % of patients were in NYHA II functional class after correction), reduces the symptoms of heart failure (93 % of patients had minimal mitral regurgitation after septal myectomy), decreases LVOT systolic pressure gradient (SPG) (the mean SPG was 18.9 ± 8.5 mmHg versus preoperative 93.6 ± 23.2 mmHg) and lowers the high-risk for SCD in the patients (the mean percentage of high-risk group was 3.78 % after correction). Routine CT planning and intraoperative transesophageal echocardiography helps to avoid severe iatrogenic complications and resect the interventricular septum as accurately as possible, completely eliminating LVOT obstruction. Conclusions. Secondary abnormal chordal attachment cutting, papillary muscle realignment and anterior mitral leaflet plication along with septal myectomy allows to fully correct all phenotype of HCM, is the safe and effective procedure as well as the definitive method of this pathology treatment minimizing the risk of disease recurrence.

Purpose of ReviewPatients with hypertrophic cardiomyopathy (HCM) who have left ventricular outflow tract obstruction (LVOTO) often experience severe symptoms and functional limitation. Relief of LVOTO can be achieved by two invasive interventions, i.e., surgery myectomy and alcohol septal ablation (ASA), leading in experienced hands to a dramatic improvement in clinical status. Despite extensive research, however, the choice of the best option in individual patients remains challenging and poses numerous clinical dilemmas.Recent FindingsInvasive strategies have been recently incorporated in recommendations for the diagnosis and treatment of HCM on both sides of the Atlantic. These guidelines are based on a bulk of well-designed but retrospective studies as well as on expert opinions. Evidence now exists that adequate evaluation and management of HCM requires a multidisciplinary team capable of choosing the best available options.SummaryManagement of LVOTO still varies largely based on local expertise and patient preference. Following the trend that has emerged for other cardiac diseases amenable to invasive interventions, the concept of a “HCM heart team” is coming of age.

Comparison of Surgical Septal Myectomy and Alcohol Septal Ablation With Cardiac Magnetic Resonance Imaging in Patients With Hypertrophic Obstructive Cardiomyopathy

AMA Alkhouli M. EditorialWill the Mitral Clip become the invasive treatment of choice for hypertrophic obstructive cardiomyopathy?. Advances in Interventional Cardiology/Postępy w Kardiologii Interwencyjnej. 2014;10(3):153-154. doi:10.5114/pwki.2014.45140. APA Alkhouli, M. (2014). EditorialWill the Mitral Clip become the invasive treatment of choice for hypertrophic obstructive cardiomyopathy?. Advances in Interventional Cardiology/Postępy w Kardiologii Interwencyjnej, 10(3), 153-154. https://doi.org/10.5114/pwki.2014.45140 Chicago Alkhouli, Mohamad. 2014. "EditorialWill the Mitral Clip become the invasive treatment of choice for hypertrophic obstructive cardiomyopathy?". Advances in Interventional Cardiology/Postępy w Kardiologii Interwencyjnej 10 (3): 153-154. doi:10.5114/pwki.2014.45140. Harvard Alkhouli, M. (2014). EditorialWill the Mitral Clip become the invasive treatment of choice for hypertrophic obstructive cardiomyopathy?. Advances in Interventional Cardiology/Postępy w Kardiologii Interwencyjnej, 10(3), pp.153-154. https://doi.org/10.5114/pwki.2014.45140 MLA Alkhouli, Mohamad. "EditorialWill the Mitral Clip become the invasive treatment of choice for hypertrophic obstructive cardiomyopathy?." Advances in Interventional Cardiology/Postępy w Kardiologii Interwencyjnej, vol. 10, no. 3, 2014, pp. 153-154. doi:10.5114/pwki.2014.45140. Vancouver Alkhouli M. EditorialWill the Mitral Clip become the invasive treatment of choice for hypertrophic obstructive cardiomyopathy?. Advances in Interventional Cardiology/Postępy w Kardiologii Interwencyjnej. 2014;10(3):153-154. doi:10.5114/pwki.2014.45140.