Distribution of coronary blood flow across the canine left ventricular free wall during reactive hyperemia

We measured myocardial blood flow (QLVFW) and O2 consumption of the left ventricular free wall (VO2, LVFW) in 13 chronically instrumented, 7-wk-old lambs with an aortopulmonary left-to-right shunt (S) and in 10 control lambs without a shunt (C). The measured VO2, LVFW was compared with the calculated values obtained by two predictive indexes, the rate-pressure product (RPP) and the pressure-work index (PWI). Measured VO2, LVFW in S lambs was significantly higher than in C lambs [983 +/- 104 (SE) vs. 475 +/- 57 mumol X min-1 X 100 g LV-1, P less than 0.001]. This was achieved by the significantly higher QLVFW (294 +/- 33 vs. 145 +/- 15 ml X min-1 X 100 g LV-1, P less than 0.002), since the arteriovenous O2 difference across the left ventricular free wall was similar in both groups of lambs. Total coronary blood flow per unit body mass in S lambs was higher than in C lambs (14.1 +/- 1.5 vs. 5.6 +/- 0.6 ml X min-1 X kg-1, P less than 0.001), not only because of the increased VO2, LVFW per unit muscle mass, but also because of the increased total heart weight (102.4 +/- 6.4 vs. 81.2 +/- 4.9 g, P less than 0.02). Correct estimation of VO2, LVFW by means of the RPP and the PWI was only possible in C lambs. In S lambs the estimated values were significantly lower than the measured ones.(ABSTRACT TRUNCATED AT 250 WORDS)

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Regional blood flow and metabolite levels in the left ventricular free wall and septum during aortic insufficiency: Implications for the development of asymmetric septal hypertrophy

Journal of the American College of Cardiology ◽

10.1016/s0735-1097(86)80399-0 ◽

1986 ◽

Vol 8 (5) ◽

pp. 1182-1188 ◽

Cited By ~ 3

Author(s):

Robert B. Dunn

Keyword(s):

Blood Flow ◽

Regional Blood Flow ◽

Aortic Insufficiency ◽

Left Ventricular ◽

Ventricular Free Wall ◽

Free Wall ◽

Left Ventricular Free Wall ◽

Asymmetric Septal Hypertrophy ◽

Septal Hypertrophy

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Lower limits of blood flow autoregulation in different myocardial layers of the left ventricular free wall of dogs

Acta Physiologica Scandinavica ◽

10.1111/j.1748-1716.1981.tb06828.x ◽

1981 ◽

Vol 112 (3) ◽

pp. 349-350 ◽

Cited By ~ 10

Author(s):

STIG HAUNSØ

Keyword(s):

Blood Flow ◽

Left Ventricular ◽

Ventricular Free Wall ◽

Free Wall ◽

Left Ventricular Free Wall ◽

Myocardial Layers ◽

Lower Limits

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Regional oxygen consumption and supply in the dog heart: effect of atrial pacing

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1979.236.2.h231 ◽

1979 ◽

Vol 236 (2) ◽

pp. H231-H237 ◽

Cited By ~ 4

Author(s):

H. R. Weiss

Keyword(s):

Blood Flow ◽

Coronary Blood Flow ◽

Left Ventricular ◽

Atrial Pacing ◽

O2 Consumption ◽

Free Wall ◽

Left Ventricular Free Wall ◽

O2 Extraction ◽

Relationship Of ◽

The Relationship

The effects of atrial pacing on the relationship of O2 supply to demand were studied on a regional basis in the dog heart. Experiments were conducted on fourteen hearts, seven in control pentobarbital-anesthetized, open-chest dogs and seven in dogs paced at 225 beats/min. Regional O2 extraction was determined by a microspectrophotometric method, and coronary blood flow was measured with radioactive microspheres. There was an 89% increase in coronary blood flow, a small but significant decrease in O2 extraction, and an increase in O2 consumption with atrial pacing. With pacing the increase in blood flow and the decrease in O2 extraction were uniform throughout the heart. In control hearts, right ventricular blood flow and O2 consumption were lower than the mean in the septal or left ventricular free wall. In the left ventricular free wall in control, the subepicardial region had a lower O2 consumption and O2 extraction than the subendocardial region. These differences were also preserved during pacing. Due to the large increase in coronary blood flow, the relationship of oxygen supply to demand was improved by atrial pacing.

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Intracellular EDEMA does not adversely affect the ability to cryopreserve intact hearts

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100147235 ◽

1993 ◽

Vol 51 ◽

pp. 278-279

Author(s):

CL Hastings ◽

RD Carlton ◽

FG Lightfoot ◽

AF Tryka

Keyword(s):

Cell Injury ◽

Median Sternotomy ◽

Left Ventricular ◽

Ventricular Free Wall ◽

Hypoxic Cell ◽

Free Wall ◽

Sprague Dawley ◽

Left Ventricular Free Wall ◽

Sprague Dawley Rats

The earliest ultrastructural manifestation of hypoxic cell injury is the presence of intracellular edema. Does this intracellular edema affect the ability to cryopreserve intact myocardium? To answer this guestion, a model for anoxia induced intracellular edema (IE) was designed based on clinical intraoperative myocardial preservation protocol. The aortas of 250 gm male Sprague-Dawley rats were cannulated and a retrograde flush of Plegisol at 8°C was infused over 90 sec. The hearts were excised and placed in a 28°C bath of Lactated Ringers for 1 h. The left ventricular free wall was then sliced and the myocardium was slam frozen. Control rats (C) were anesthetized, the hearts approached by median sternotomy, and the left ventricular free wall frozen in situ immediately after slicing. The slam frozen samples were obtained utilizing the DDK PS1000, which was precooled to -185°C in liguid nitrogen. The tissue was in contact with the metal mirror for a dwell time of 20 sec, and stored in liguid nitrogen until freeze dry processing (Lightfoot, 1990).

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Echocardiographic Findings in Friedreich's Ataxia

Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques ◽

10.1017/s0317167100025543 ◽

1976 ◽

Vol 3 (4) ◽

pp. 329-332 ◽

Cited By ~ 25

Author(s):

H.F. Gattiker ◽

A. Davignon ◽

A. Bozio ◽

J. Batlle-Diaz ◽

G. Geoffroy ◽

...

Keyword(s):

Friedreich’S Ataxia ◽

Left Ventricular ◽

Friedreich's Ataxia ◽

Ventricular Free Wall ◽

Slight Reduction ◽

Free Wall ◽

Left Ventricular Free Wall ◽

Echocardiographic Examination ◽

Septal Hypertrophy ◽

Echocardiographic Findings

SUMMARY:Echocardiographic examination of 21 patients with Friedreich's ataxia (age 7 to 28 years) showed cardiac abnormalities in 90% of the cases. They were characterized by varying degrees of septal hypertrophy in 81%, left ventricular free wall hypertrophy in 61%, and a slight reduction of left ventricular internal dimension in 57% of the cases. Asymmetric septal hypertrophy (ASH) with a septal/left ventricular free wall ratio of over 1.3 was found in 29% of the cases, and systolic anterior motion (SAM) of the mitral valve in three patients. Two other patients showed evidence of a different type of cardiomyopathy with marked symmetric left ventricular hypertrophy and marked left ventricular enlargement.

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