Morphology and Classification of Right Ventricular Bands in the Domestic Dog (Canis familiaris )

Abstract

Ventricular bands, also designated as 'false tendons', are described as single or multiple strands that cross the ventricles and have no connection to valvular cusps. Previous work indicates these strands are present in the ventricles of humans and some animal hearts and not always associated with cardiac pathologies. Despite these previous studies, the published literature is limited in documenting the morphology of these strands and incidence in animals. In this study, examination of 89 hearts showed six types of ventricular bands in the right ventricle of the domestic dog. These bands were classified according to their prevalence and points of attachment. Type I extended from the interventricular septum to the ventricular free wall, type II connected a musculus papillaris parvus to the ventricular free wall and type III connected trabeculae carneae on the interventricular septum. Type IV connected the trabeculae carneae on the ventricular free wall, type V interconnected papillary muscles and type VI connected the interventricular septum to a papillary muscle. While the study of these ventricular bands provided additional information on the cardiac anatomy of the domestic dog, it also showed their clinical importance. Several studies have proposed that their position in the ventricle may interfere with cardiac catheterization and pacemaker lead placement or be misinterpreted during echocardiography.

Anatomical variations and pathological changes in the hearts of free-ranging Eurasian lynx (Lynx lynx) in Finland

“…Ventricular bands are thin, fibrous or fibromuscular bands that traverse the cavity of the left side and ventricles in humans and many other mammals (Kervancioğlu et al 2003;Deniz et al 2004;Philip et al 2011;Cope 2017). Kimura et al (2016) Fig .…”

“…Most of the publications on ventricular bands focus on the left ventricle, possible because there the bands are larger and more visible (Kosiński et al 2012). However, these bands are commonly found in right ventricle of the domestic dogs, where they typically extend from the interventricular septum to the ventricular free wall (Cope 2017). These fibrous bands are a frequent finding in left ventricle of cats, where they extend between the papillary muscles and the ventricular septum (Gerlis et al 1984;Kimura et al 2016).…”

Cardiac ventricular false tendons: A meta‐analysis

“…Katholi et al (1979) obtained free‐running false tendons from the right ventricular free wall and septum of 20 canine hearts. Cope (2017) found right ventricular bands in 85 of 89 canine hearts. The tendons were classified into varieties of 6 types.…”

Distribution and morphology of ventricular bands in the hearts of ringed seals

“…The bands in the left ventricle have been studied more extensively, apparently because they are more common, larger and more visible than the ones found in the right ventricle (Kosiński et al., 2012). In domestic dogs, several band types and multiple ventricular band combinations have been described (Cope, 2017). Because of the gross similarity of ventricular bands and trabeculae septomarginalis in animals (Cope, 2019), histological studies are needed to differentiate these anatomical structures.…”