Hypertrophic cardiomyopathy: state‐of‐the‐art review, with focus on the management of outflow obstruction

Abstract

Significant advances in our understanding and management of hypertrophic cardiomyopathy have been made in the last decade, as the complex genetics and phenotype-genotype correlations that characterize the disease are gradually unravelled. The well-described clinical heterogeneity of hypertrophic cardiomyopathy is now understood to be based on profound genetic variability, with at least 10 genes and over 150 mutations implicated. Several new therapeutic tools have entered clinical practice. The implantable cardioverter-defibrillator is now strongly indicated in those at high risk of sudden arrhythmic death. Our ability to abort sudden death in this subgroup has placed added emphasis on risk stratification in newly diagnosed patients. New procedures have also been developed for the relief of outflow obstruction in patients with refractory symptoms and a significant subaortic outflow gradient. Although not as efficacious as the 'gold-standard' surgical myectomy-myotomy, dual-chamber pacemaker implantation can be of modest benefit in select patients. Percutaneous transluminal septal myocardial ablation is an emerging catheter-based procedure for the relief of left ventricular outflow obstruction. Long-term follow-up data are still awaited. However, intermediate-term results suggest equivalent efficacy to surgical myectomy-myotomy.

Quantitative and Qualitative Changes in the Resting Electrocardiograph After Percutaneous Transluminal Septal Myocardial Ablation for the Treatment of Symptomatic Obstructive Hypertrophic Cardiomyopathy

“…14 Although PTSMA reduces symptoms 13,14,16,18 and improves echocardiographic parameters, 1,14,19 there is a theoretical potential for arrhythmogenesis due to the alcohol induced myocardial scar in the ventricular septum. [8][9][10] However, there is no evidence in the literature that alcohol ablation gives rise to an arrhythmogenic substrate from electrophysiological studies performed after PTSMA. 2 In our study three patients (7%) developed periprocedural VF from which they were successfully cardioverted.…”

Classifying HCM Subtypes via Left Ventricular Two-dimensional Curvature and Dynamic Time Wrapping

“…Being a primary disease of the cardiac sarcomere [1,2], Hypertrophic cardiomyopathy (HCM) affects approximately one individual out of 500. The annual mortality rate is approximately 1-2% [3].…”

DDD Pacing Therapy Could Serve as a Dual Purpose Treatment in Hypertrophic Obstructive Cardiomyopathy-A Case Report Which Suggests the Importance of Lead Position and the Mechanism-

“…Although therapies such as percutaneous myocardial ablation and surgical manipulation effectively reduce the LVOT gradient, they carry a risk of mortality and morbidity. [1][2][3] On the other hand, pacing therapy has is less invasive than the therapies mentioned above because it causes no rapid or irreversible anatomical changes. However, results of recent randomized studies have not been uniform and are considered controversial.…”