The Effects of Pacing Site on Left Ventricular Epicardial Surface Velocity Patterns During Systole

The route efferent vagal fibers travel to reach the left ventricle is not clear and was the subject of this investigation. We measured left ventricular and septal effective refractory period (ERP) changes during vagal stimulation and a constant infusion of norepinephrine, before and after phenol was applied at selected sites of the heart to interrupt efferent vagal fibers that may be traveling in that area. Phenol applied to the atrioventricular (AV) groove between the origin of the right coronary artery anteriorly to the posterior descending branch of the circumflex coronary artery completely eliminated vagal-induced prolongation of ERP in the anterior and posterior left ventricular free wall and reduced, but did not eliminate, ERP prolongation in the septum. A large (3-cm radius) epicardial circle of phenol prevented vagal-induced ERP prolongation within the circle in all dogs, while a small (1-cm radius) epicardial circle of phenol failed to prevent vagal-induced ERP changes within the circle in any dog. An intermediate (2-cm radius) circle eliminated vagal effects on ERP in 13 of 18 dogs. Arcs of phenol, to duplicate the upper portion of the circle, applied sequentially from apex to base eliminated efferent vagal effects only when painted near or at the AV groove. We conclude that the majority of efferent vagal fibers enroute to innervate the anterior and posterior left ventricular epicardium cross the AV groove within 0.25-0.5 mm (depth of phenol destruction) of the epicardial surface.(ABSTRACT TRUNCATED AT 250 WORDS)

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Improved Quantification of Left Ventricular Volumes and Mass Based on Endocardial and Epicardial Surface Detection from Cardiac MR Images Using Level Set Models

Journal of Cardiovascular Magnetic Resonance ◽

10.1081/jcmr-200060624 ◽

2005 ◽

Vol 7 (3) ◽

pp. 595-602 ◽

Cited By ~ 17

Author(s):

Cristiana Corsi ◽

Claudio Lamberti ◽

Oronzo Catalano ◽

Peter MacEneaney ◽

Dianna Bardo ◽

...

Keyword(s):

Level Set ◽

Left Ventricular ◽

Left Ventricular Volumes ◽

Mr Images ◽

Ventricular Volumes ◽

Cardiac Mr ◽

Surface Detection ◽

Epicardial Surface

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Changes in left ventricular geometry during spontaneous breathing

Journal of Applied Physiology ◽

10.1152/jappl.1987.63.2.803 ◽

1987 ◽

Vol 63 (2) ◽

pp. 803-811 ◽

Cited By ~ 11

Author(s):

S. S. Cassidy ◽

W. B. Wead ◽

G. B. Seibert ◽

M. Ramanathan

Keyword(s):

Lateral Wall ◽

Left Ventricular ◽

Left Ventricular Geometry ◽

Dimensional Changes ◽

Ventricular Geometry ◽

Epicardial Surface ◽

Right Ventricular Filling ◽

Base Dimension ◽

Lateral Portion ◽

Ventricular Filling

The purpose of these experiments was to determine the effects of a spontaneously generated inspiration on the size and shape of the left ventricle (LV) in anesthetized supine dogs. We implanted markers in the LV to establish three perpendicular axes and recorded the motion of these markers using biplane cinefluoroscopy at 60 Hz. The primary changes in LV size that accompanied inspiration occurred at end diastole (ED). The largest change in LVED dimension was a 2.46-mm narrowing of the septal-lateral wall dimension, but the apex-base dimension decreased also, by 0.74 mm. The anteroposterior dimension actually widened by 1.07 mm. The septal-lateral narrowing was caused by both a 1.0-mm narrowing of the distance between the septal marker and the apex-base axis, as well as by a 1.4-mm narrowing between the apex-base axis and the lateral wall marker. Narrowing of the septal portion seemed expected because of presumed enhanced right ventricular filling during inspiration. Narrowing of the lateral portion of the LV, while the anteroposterior dimension widened, was surprising because a change in LVEDV shape is implied. Assuming ventricular homogeneity, this change in LVED shape implies that the forces applied to the epicardial surface were not uniform. There must have been a retraction on the anterior and posterior surface that was not experienced by the lateral LV wall. The net effect of these dimensional changes of the LV at end diastole (estimated from the product of the three ED axes) was a 3.5-cm3 reduction in LVED volume.(ABSTRACT TRUNCATED AT 250 WORDS)

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A computer model of the left ventricular epicardial surface for quantification of jeopardized myocardium

Computer Programs in Biomedicine ◽

10.1016/0010-468x(82)90015-0 ◽

1982 ◽

Vol 14 (2) ◽

pp. 127-132

Author(s):

S. Matts ◽

E. Sjolander ◽

Geun C. Jang

Keyword(s):

Computer Model ◽

Left Ventricular ◽

Epicardial Surface

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Scale ratio ICP for 3D registration of coronary venous anatomy with left ventricular epicardial surface to guide CRT lead placement (Erratum)

Medical Imaging 2019: Image-Guided Procedures, Robotic Interventions, and Modeling ◽

10.1117/12.2540856 ◽

2019 ◽

Keyword(s):

Left Ventricular ◽

3D Registration ◽

Venous Anatomy ◽

Epicardial Surface ◽

Lead Placement ◽

Scale Ratio

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Improved quantification of left ventricular mass based on endocardial and epicardial surface detection with real time three dimensional echocardiography

Heart ◽

10.1136/hrt.2005.060889 ◽

2006 ◽

Vol 92 (2) ◽

pp. 213-219 ◽

Cited By ~ 59

Author(s):

E G Caiani

Keyword(s):

Real Time ◽

Left Ventricular Mass ◽

Three Dimensional ◽

Left Ventricular ◽

Surface Detection ◽

Epicardial Surface ◽

Ventricular Mass ◽

Dimensional Echocardiography ◽

Three Dimensional Echocardiography

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Epicardial surface velocity mapping

Journal of Electrocardiology ◽

10.1016/0022-0736(92)90074-a ◽

1992 ◽

Vol 25 ◽

pp. 111 ◽

Cited By ~ 1

Author(s):

Michael D. Herr ◽

Joseph J. McInerney ◽

Jerry C. Luck ◽

Jeffrey D. Orledge ◽

Gary L. Copenhaver

Keyword(s):

Surface Velocity ◽

Velocity Mapping ◽

Epicardial Surface

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A method to assess endocardial regional longitudinal curvature of the left ventricle

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1995.268.6.h2553 ◽

1995 ◽

Vol 268 (6) ◽

pp. H2553-H2560 ◽

Cited By ~ 1

Author(s):

A. DeAnda ◽

M. R. Moon ◽

S. D. Nikolic ◽

L. J. Castro ◽

J. I. Fann ◽

...

Keyword(s):

Steady State ◽

A Priori ◽

Three Dimensional ◽

Left Ventricular ◽

Lv Function ◽

Regional Heterogeneity ◽

Dynamic Changes ◽

Epicardial Surface ◽

Endocardial Surface ◽

Lv Volume

Knowledge of the instantaneous geometry of the left ventricular (LV) chamber is necessary to calculate LV function and wall stresses. We describe a method utilizing myocardial markers that does not rely on any a priori assumptions of global LV geometry. Five dogs underwent placement of 25 endocardial and 3 epicardial miniature LV markers. Six weeks later, the animals were studied during conscious closed-chest conditions. The three-dimensional coordinates of the LV markers were used to compute longitudinal fitted curves for LV walls and septum during steady-state conditions; endocardial radii of curvature (rcurv) were then computed for each region at the midequatorial (rcurv-eq) and apical levels. There was a uniform decrease in rcurv in each LV wall during systole (compared with diastole, P < 0.01); at end systole, rcurv was regionally heterogeneous between opposing walls, e.g., anterior and posterior rcurv-eq values were 17.2 +/- 2.0 and 17.7 +/- 1.8 (SD) cm, respectively (P < 0.05). At end diastole, only septal-lateral rcurv-eq was different (16.9 +/- 2.1 vs. 18.7 +/- 1.3 cm: P < 0.05). Normalization of rcurv (to instantaneous LV volume) removed the systolic-diastolic differences, but a similar pattern of regional heterogeneity persisted. The data presented pertain to the LV endocardial surface, but the method described can be applied to the epicardial surface as well; this new method offers promise in assessing dynamic changes in longitudinal LV endocardial curvature.

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