Significance of left ventricular apical–basal muscle bundle identified by cardiovascular magnetic resonance imaging in patients with hypertrophic cardiomyopathy

Abstract

Apical-basal muscle bundles are a unique myocardial structure commonly present in HCM patients as well as in G+/P- family members and may represent an additional morphologic marker for HCM diagnosis in genotype-positive status.

Hypertrophic cardiomyopathy: a heart in need of an energy bar?

“…A variety of functional defects, including altered Ca 2+ sensitivity and/or affinity, myofibrillar ATPase activity, Ca 2+ handling, cross-bridge dynamics, impaired energetics, oxidative stress and electrophysiologic abnormalities have been identified in experimental models (Straceski et al, 1994; Spindler et al, 1998; Blanchard et al, 1999; Gao et al, 1999; Georgakopoulos et al, 1999; Tardiff et al, 1999; Solaro et al, 2002; Javadpour et al, 2003; Adhikari et al, 2004; Szczesna-Cordary et al, 2004; Ertz-Berger et al, 2005; Hernandez et al, 2005; Robinson et al, 2007; Greenberg et al, 2009, 2010; Guinto et al, 2009; Mettikolla et al, 2011; Puglisi et al, 2014) and patients (Haq et al, 2001; Crilley et al, 2003; Nakamura et al, 2005; Dimitrow et al, 2009; Unno et al, 2009; Ho et al, 2010; Bravo et al, 2012; Coppini et al, 2013; Lin et al, 2013; Gruner et al, 2014). Since HCM-causing mutations increase the energetic cost of tension development, it has been hypothesized that excessive sarcomeric energy use leads to the HCM phenotype (Blair et al, 2001; Crilley et al, 2003; Abozguia et al, 2010).…”

A new phenotypic marker of hypertrophic cardiomyopathy

“…An accessory left-ventricular muscle bundle was defi ned as a single band of muscle extending through the leftventricular cavity from the apex to the basal septum or the anterior wall of the left ventricle. 6 Such apical-basal muscle bundles were present in 145 (63%) of 230 HCM patients, with similar proportions in patients younger than 20 years and in those older than 60 years. Bundles were also seen in 18 (60%) of 30 genotype-positive, phenotype-negative family members, and in 12 (10%) of 126 controls.…”

“…Gruner and colleagues' study 6 adds another useful morphological marker to aid in the clinical diagnosis of a common inherited cardiac disease. Although MRI provides a comprehensive assessment of intracardiac anatomy in HCM patients, no single anatomical observation can be deemed completely specifi c for the disease.…”

Aspectos poco conocidos de la miocardiopatía hipertrófica

“…La inserció n anó mala de las cuerdas tendinosas y los MP en las valvas plantea la cuestió n de si la obstrucció n resultante debe abordarse tambié n con una intervenció n en el aparato subvalvular, aparte de la operació n de miectomía. De igual modo, parece razonable eliminar quirú rgicamente los factores que favorecen el desplazamiento anterior del MP anterolateral, es decir, la extirpació n de las conexiones y los haces musculares 10,12 , o la liberació n parcial del punto de inserció n del MP en la pared del VI 10,12 .…”