Search Results (3)

Left ventricular (LV) longitudinal function is mechanically coupled to the elasticity of the ascending aorta (AA). The pathophysiologic link between a stiff AA and reduced longitudinal strain and the subsequent deterioration in longitudinal LV systolic function is likely relevant in heart failure with preserved ejection fraction (HFpEF). The proposed therapeutic effect of freeing the LV apex and allowing for LV inverse longitudinal shortening was studied in silico utilizing the Living Left Heart Human Model (Dassault Systémes Simulia Corporation). LV function was evaluated in a model with (A) an elastic AA, (B) a stiff AA, and (C) a stiff AA with a free LV apex. The cardiac model simulation demonstrated that freeing the apex caused inverse LV longitudinal shortening that could abolish the deleterious mechanical effect of a stiff AA on LV function. A stiff AA and impairment of the LV longitudinal strain are common in patients with HFpEF. The hypothesis-generating model strongly suggests that freeing the apex and inverse longitudinal shortening may improve LV function in HFpEF patients with a stiff AA. Full article

During systole, longitudinal shortening of the left ventricle (LV) displaces the aortic root toward the apex of the heart and stretches the ascending aorta (AA). An in silico study (Living Left Heart Human Model, Dassault Systèmes Simulia Corporation) demonstrated that stiffening of the AA affects myocardial stress and LV strain patterns. With AA stiffening, myofiber stress increased overall in the LV, with particularly high-stress areas at the septum. The most pronounced reduction in strain was noted along the septal longitudinal region. The pressure–volume loops showed that AA stiffening caused a deterioration in LV function, with increased end-systolic volume, reduced systolic LV pressure, decreased stroke volume and effective stroke work, but elevated end-diastolic pressure. An increase in myofiber contractility indicated that stroke volume and effective stroke work could be recovered, with an increase in LV end-systolic pressure and a decrease in end-diastolic pressure. Longitudinal and radial strains remained reduced, but circumferential strains increased over baseline, compensating for lost longitudinal LV function. Myofiber stress increased overall, with the most dramatic increase in the septal region and the LV apex. We demonstrate a direct mechanical pathophysiologic link between stiff AA and reduced longitudinal left ventricular strain which are common in patients with HFpEF. Full article

Introduction. The tricuspid valve is an atrioventricular valve located on the right side of the heart, which consists of the fibrous tricuspid annulus (TA), three valvular leaflets and a supporting apparatus, the papillary muscles and the tendinous chords. The TA is an oval-shaped three-dimensional (3D) fibrous structure with a complex spatial movement during the cardiac cycle. Three-dimensional echocardiography (3DE) could help during “en-face” assessment of TA dimensions and related functional properties featuring its “sphincter-like” function. TA plane systolic excursion (TAPSE) is a displacement of the lateral edge of the TA toward the apex in systole measured in apical long-axis using M-mode echocardiography (MME). The aim of this study was to determine potential relationships between TA size and its “sphincter-like” and “longitudinal” functions in healthy adults with no functional tricuspid regurgitation. Methods. The present study consisted of 119 healthy patients (age: 34.6 ± 11.5 years, 70 men) who underwent routine echocardiography with M-mode-derived TAPSE measurement and 3DE. Two subgroups of healthy subjects were compared with each other. A total of 29 subjects with TAPSE between 17 and 21 mm were compared with 90 cases with TAPSE ≥ 22 mm. Results. Subjects with TAPSE of 17–21 mm had tendentiously dilated TA dimensions compared with subjects with TAPSE ≥ 22 mm. Significant differences could be detected in the end-systolic TA area (5.85 ± 1.90 cm² vs. 3.70 ± 1.22 cm², p < 0.05), leading to impaired TAFAC (24.8 ± 9.0% vs. 35.1 ± 9.1%, p < 0.05) in subjects with lower TAPSE (17–21 mm) compared with subjects with TAPSE ≥ 22 mm. TAPSE did not show correlations with any TA size or “sphincter-like” functional parameters as determined using 3DE. Conclusions. Three-dimensional echocardiography is capable of measuring TA dimensions and functional “sphincter-like” properties, which are associated with MME-derived TAPSE, suggesting a sensitive and harmonic TA function in healthy adults without functional tricuspid regurgitation. Full article