Hypertrophic cardiomyopathy (HCM) is the most common genetic heart disease, with a prevalence of 1 case in 500 individuals. The disease is very heterogeneous regarding its phenotype, being the main cause of sudden death in athletes who they die in competitions.^, Fortunately, most patients are asymptomatic or have few symptoms and will have a life expectancy very close to the individuals without the disease. However, some patients will develop symptoms such as angina, dyspnea, palpitations, syncope and even sudden death, usually caused by ventricular arrhythmia. Approximately 2/3 of patients with HCM have a significant left ventricular outflow tract (LVOT) gradient at rest or during drug or physical exertion provocation tests. The presence of a significant gradient, mainly at rest, characterizes obstructive hypertrophic cardiomyopathy (OHCM) and the presence of the gradient is related to greater symptom intensity and a higher risk of death.^–

The standard treatment of symptomatic patients comprise the use of drugs such as beta-blockers and/or calcium channel blockers, which decrease the gradient and improve angina, diastolic function and increase tolerance to physical exertion.^– Between 5 and 10% of patients with OHCM are refractory to pharmacological treatment and should be considered for invasive treatment: surgical myomectomy (SM) or septal ablation (SA) (alcoholization) with the aim of reducing septal muscle mass and relieve LVOT obstruction.^, Since its introduction in 1995 by Sigwart et al., SA has become an alternative to surgical treatment (which was considered the gold standard treatment for patients with OHCM and refractory to clinical treatment). After the introduction of SA, because it was found to be attractive to the patient and to the physician, a rapid and progressive increase in the number of performed procedures was observed, especially in the European countries, which quickly surpassed the number of surgeries performed annually worldwide and with results in the short and medium term that were similar to the results obtained with surgical procedures in centers of excellence, according to data from patient cohorts, registries and meta-analyses,^, since there are no randomized trials comparing the two forms of intervention. But despite the significant increase in the number of SA performed and after two decades of experience, some controversy remains about the choice of invasive procedure (SA or SM?).^,–

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