Key result
End-systolic wall stress significantly misrepresented fiber stress in patients with abnormal LV thickness-to-dimension ratios (r = 0.78, P < 0.001), underestimating it when h/D was increased.
Why the study?
Does wall stress accurately represent fiber stress (afterload) in children and young adults with abnormal left ventricular geometry?
Observational (n=207)
Does wall stress accurately represent fiber stress (afterload) in children and young adults with abnormal left ventricular geometry?
Wall stress misrepresents true afterload (fiber stress) in patients with abnormal ventricular geometry, underestimating it when wall thickness is increased and overestimating it when decreased.
Clinicians should prefer fiber stress over wall stress for afterload assessment in abnormal LV geometry; challenges conventional indices and extends myocardial mechanics research.
Wall stress, although commonly used as an index of afterload, fails to take into account forces generated within the wall of the left ventricle (LV) that oppose systolic fiber shortening. Wall stress may, therefore, misrepresent fiber stress, the force resisting fiber shortening, particularly in the presence of an abnormal LV thickness-to-dimension ratio (h/D). M-mode LV echocardiograms were obtained from 207 patients with a wide range of values for LV mass and/or h/D. Diagnoses were valvar aortic stenosis, coarctation repair, anthracycline treated, and severe aortic and/or mitral regurgitation. End-systolic wall stress (WS(es)) and fiber stress (FS(es)) were expressed as age-corrected Z scores relative to a normal population. The difference between WS(es) and FS(es) was extreme when h/D was elevated or reduced [WS(es) Z score - FS(es) Z score = 0.14 x (h/D)(-1.47) - 2.13; r = 0.78, P < 0.001], with WS(es) underestimating FS(es) when h/D was increased and overestimating FS(es) when h/D was decreased. Analyses of myocardial mechanics based on wall stress have limited validity in patients with abnormal ventricular geometry.
No takes yet. Share an insight, caveat, or question.
Gentles et al. (2002) conducted an observational in Abnormal left ventricular geometry (n=207). Abnormal LV thickness-to-dimension ratio (h/D) vs. Normal LV geometry was evaluated on Difference between end-systolic wall stress (WS(es)) and fiber stress (FS(es)) Z scores (r = 0.78, p=< 0.001). End-systolic wall stress significantly misrepresented fiber stress in patients with abnormal LV thickness-to-dimension ratios (r = 0.78, P < 0.001), underestimating it when h/D was increased.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: