China
Africa
Explore chapters and articles related to this topic
The Role of Cardiac Magnetic Resonance in Hypertrophic Cardiomyopathy
Published in Srilakshmi M. Adhyapak, V. Rao Parachuri, Hypertrophic Cardiomyopathy, 2020
Gulhane Avanti, Lakhani Zeeshan, Raj Vimal
The most common phenotype of HCM is asymmetric septal hypertrophy, followed by mid-ventricular, apical, concentric, and mass-like subtypes (Figure 5.1) [9]. Cardiac magnetic resonance can identify segmental or diffuse areas of hypertrophy within LV, especially at the anterolateral free wall, apex, or posterior septum which cannot be reliably identified by 2D echocardiogram [10]. It can avoid overestimation of LV wall thickness when the crista supraventricularis, a right ventricular muscle structure, is situated adjacent to the ventricular septum and inappropriately included in the septal measurements on echocardiography [11]. Cardiac magnetic resonance offers excellent demonstration of LV apical aneurysms [12] and apical thrombi [13] and is more sensitive in the detection of subtle markers of HCM disease, such as hypertrabeculations and myocardial crypts [14]. Further, it is possible to perform genotype–phenotype analysis of HCM on CMR; patients with any genetic mutation are likely to demonstrate reverse curvature HCM in comparison to sigmoidal HCM or apical HCM (Figure 5.2) [15].
Interventions for congenital heart disease
Published in John Edward Boland, David W. M. Muller, Interventional Cardiology and Cardiac Catheterisation, 2019
Defects of the ventricular septum are among the most common congenital cardiac anomalies seen clinically. Sub-pulmonary or ‘supracristal’ defects lie above a muscular ridge in the right ventricular outflow tract called the crista supraventricularis. Defects below the crista may be in the region of the membranous septum (‘membranous’ VSDs) or in the muscular portion of the septum (‘muscular’ VSDs). Membranous VSDs are the most common form; muscular VSDs are commonly multiple. Like atrial septal defects, VSDs are generally well tolerated, although severe pulmonary hypertension and shunt reversal (Eisenmenger’s syndrome) may occur. Many children with congenital VSDs do not require treatment, since spontaneous closure often occurs during the first decade of life. However, defects that are still present at 8–10 years of age are unlikely to close spontaneously and should be closed if a functionally significant left-to-right shunt is detected. Surgical closure is generally well tolerated, but is associated with significant morbidity and mortality, especially if multiple muscular defects are present.20
The Normal Heart
Published in P. Chopra, R. Ray, A. Saxena, Illustrated Textbook of Cardiovascular Pathology, 2013
The left ventricle (Figs 1.2 and 1.4) The left ventricle also has an inlet, apical trabecular and outlet components. Unlike the right ventricle, the inlet and outlet portions are not demarcated by the muscular cuff of the crista supraventricularis. The inlet extends from the atrioventricular junction to the a tachment of the papillary muscles. The most characteristic feature to decide the morphological leftness is the fine trabecular nature of the apical component. The septal surface of the left ventricle is smooth as it does not have a septomarginal trabeculation or a moderator band. Another characteristic feature of the left ventricle is that the mitral va ve never possesses chordal attachments to the septum. The membranous part of the interventricular septum is best identified from this chamber, which lies between the right coronary and non-coronary cusps. The outlet component of the left ventricle is
Right ventricular involvement in hypertrophic cardiomyopathy: evidence and implications from current literature
Published in Scandinavian Cardiovascular Journal, 2021
Simon Girmai Berger, Ivar Sjaastad, Mathis Korseberg Stokke
In most cases, RVWT in HCM patients correlates with LVWT [28,36]. As a rule, LVH is more pronounced than RVH [36], although case-reports with a total of five patients described dominant or even isolated RVH [51–54]. The underlying diagnosis and the relationship to HCM in these cases is unclear. In approximately 42% of HCM patients, RV outflow tract (RVOT) obstruction is observed concomitantly with LVOT obstruction [33]. RVOT obstruction in HCM is caused by ventricular cavity reduction due to hypertrophy of the interventricular septum, RV free wall or/and crista supraventricularis [55,56]. According to case reports, RVOT obstruction can occur alone or combined with LV intracavitary obstruction [51,57]. While LVOT is predominantly characterized by a dynamic obstruction caused by the systolic anterior motion (SAM) of the mitral valve, RVOT obstruction is predominantly static [55,58]. As for the LV, the morphological presentation of HCM in the RV is variable and heterogeneous [59]: RVH in HCM can be localized to the free wall, inferior septum wall or apex of the ventricle [36]. However, a substantial number of patients have a diffuse pattern, where the hypertrophy is present in all three segments [36]. Histopathological examinations of the myocardium in HCM describe asymmetrical and focal abnormalities both in the LV and RV [60]. Cardiomyocyte alignment is distorted, and cardiomyocytes are enlarged, disoriented and abnormally shaped (See inset in Figure 2) [60].
Evaluation of the right ventricle by echocardiography: particularities and major challenges
Published in Expert Review of Cardiovascular Therapy, 2018
Mechanical and timing heterogeneity even in normal RVs make the assessment of RV function very challenging. Normally, conus contraction contributes less than 15% of RV SV [1]. RV performance is substantially influenced by the LV via ventricular interdependence enabled by common muscle fiber and the constrain of the ventricles by the pericardial sac. The crista supraventricularis functions as a contractile strut, transmitting septal contraction to the free wall. Via the crista, LV contraction narrows the TA and pulls the RV free wall toward the septum, promoting RV contraction and TV competence [1]. Due to this ventricular interdependence, LV contraction normally allows the LV to contribute for ~30% of pressure generation in the RV and thus, even akinetic RVs can generate some intracavitary systolic pressure [1,20]. RV myocytes are predominantly oriented in the longitudinal direction (subendicardial layer), whereas in the thinner subepicardium, the myocytes are circumferentially oriented [5,6]. Consequently, the normal RV contraction pattern is mainly longitudinal [6,21]. Thus, whereas the LV shortens symmetrically in the transverse and longitudinal planes, normal RV contraction results principally in longitudinal shortening and resembles a piston rather than a bellows [1]. RV longitudinal shortening closely correlates with right ventricular ejection fraction (RVEF), whereas transverse shortening does not [1]. Nevertheless, chronic pressure and volume overload can result in relative hypertrophy of circumferential fibers with increase of the relative contribution of circumferential contraction and free wall translation to RV systolic function [1,22]. Acting more as a volume pump, the compliant thin-walled RV tolerates less pressure than volume over-load and has definitely higher sensitivity to afterload changes than the LV. Due to the distinctly load dependency of RV contractile function, both reduction in systolic function and ventricular enlargement occur much earlier in the pressure overloaded RV than in the pressure overloaded LV [23,24].