Close Physical Contact of the Heart with Diaphragm Causes Pseudo‐Asynergy of Left Ventricular Inferior Wall in Normal Subjects

Abstract

Paradoxical outward movement of left ventricular (LV) inferior wall in systole is occasionally recognized in normal subjects and clinically important in terms of the differential diagnosis between physiological pseudo-asynergy and pathological asynergy. In this study, the potential mechanisms by which pseudo-asynergy of LV inferior wall (PLI) is observed in normal subjects were investigated. PLI was defined as the outward movement of LV inferior wall observed during more than 50% of systole. The incidence of PLI was evaluated in 7843 consecutive subjects in routine echocardiography. The effects of body position and artificial gravity on the manifestation of PLI were also examined. PLI was observed in 0.11% (9/7842) of subjects on left lateral position. Measurement of the angle formed by LV long-axis and the long-axis of the body on frontal plane revealed that hearts in subjects with PLI were in relatively horizontal position. PLI was observed on sitting position in 43% (40/92) of subjects without PLI on left lateral position. The subjects with sitting position-induced PLI exhibited significantly higher obesity index. PLI was also induced by artificial gravity in 67% (14/21) of healthy volunteers on supine position, and the degree of PLI correlated with the intensity of gravity. Although the incidence of PLI in routine echocardiography is relatively low, PLI can be induced in normal subjects by any condition that causes close contact of LV inferior wall to diaphragm. Thus, PLI should be taken into consideration in the differential diagnosis of abnormal LV inferior wall motion, especially when performing exercise echocardiography.

A Case of LV “Pseudo” Pseudodyskinesis

“…2 During ventricular diastole, when intraventricular pressure is at its lowest, an adjacent structure under pressure might therefore cause compression of the inferior wall with subsequent superior and anterior movement. 6 To our knowledge, however, our report is the first to demonstrate pseudodyskinesis due to the presence of a thoracic aortic aneurysm. In effect, the generation of systolic pressure "pushes back" against the structure impinging on the LV and allows for the resumption of normal shape.…”

“…[3][4][5] Sakurai et al also showed that pseudodyskineis could be induced in normal subjects by any condition that caused close contact of the LV inferior wall to the diaphragm. 6 To our knowledge, however, our report is the first to demonstrate pseudodyskinesis due to the presence of a thoracic aortic aneurysm.…”

Differentiation of pseudodyskinesis of inferior left ventricular wall from inferior myocardial infarction by assessment of regional myocardial strain using two-dimensional speckle tracking echocardiography

“…In earlier research it was reported that the incidence of PD in the left lateral position was 0.11% [1]. Fig.…”

“…In routine transthoracic echocardiography (TTE), pseudodyskinesis (PD) of the inferior left ventricular (LV) wall is often observed in subjects without myocardial ischemia or myocardial infarction (MI), and is usually attributable to diastolic dysfunction with normal wall thickening resulting from close contact with the diaphragm [1]. In earlier research it was reported that the incidence of PD in the left lateral position was 0.11% [1].…”

“…This paradoxical wall motion can also be observed in the apical two chamber view. Contact of the liver with the inferior LV wall may also play a role by displacing local structures and accentuating the interaction between the heart and the diaphragm [1][2][3].…”