Quantitation of collateral and ischemic flows with microspheres and diffusible indicator

Flow to myocardium following coronary occlusion may not originate solely from collateral channels. Some flow might be derived from overlapping coronary arteries which also perfuse tissue within the territory of the obstructed vessel prior to occlusion. Left atrial microsphere injection during perfusion of the left anterior descending (LAD) artery from a special reservoir containing microsphere-free blood and again after LAD occlusion permitted measurement of noncollateral overlap and total ischemic LAD (TIF) flows, respectively, and mathematical derivation of true collateral flow (TCF). Whereas TIF averaged 0.25 +/- 0.03 ml/min per g, TCF was 0.14 +/- 0.03 ml/min per g, only 50.6% of TIF. The remainder of the TIF represented either inadvertant inclusion of normally perfused tissue with the ischemic LAD myocardium or actual overlap of LAD and left circumflex circulations. 86RbCl was injected simultaneously with the microspheres following coronary occlusion. 86Rb and microsphere densities in the whole heart and ischemic area were closely correlated, although microsphere distribution tended to be more heterogeneous. No segment of ischemic myocardium containing 86Rb was free of microspheres. Therefore, the geometry of undeveloped collateral channels is adequate to permit passage of 15-micron particles. Absolute 86Rb flows were consistently less than microsphere flows.

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The Effect Of Streptokinase On Regional Myocardial Perfusion After Coronary Ligation In Dog

10.1055/s-0038-1653169 ◽

1981 ◽

Author(s):

K Genth ◽

M Hofmann ◽

W Schaper

Keyword(s):

Heart Rate ◽

Myocardial Perfusion ◽

Coronary Arteries ◽

Ischemic Myocardium ◽

Collateral Flow ◽

Dilution Technique ◽

Regional Myocardial Perfusion ◽

Coronary Ligation ◽

Tracer Microspheres ◽

Ischemic Muscle

The Influence of streptokinase(SK) on myocardial perfusion in ischemic and non-ischemic muscle was studied in 10 open-chest dogs, on each animal a sequential occlusion of 2 medium-sized coronary arteries was performed (90 min.), followed by reperfusion. Each dog served as its own control. After occlusion and reperfusion of the control artery (CA), the inital dose of SK was given (1,5 mega IU/20 min.). Thereafter test artery (TA) was occluded, followed by a maintenance dose of SK (500.000 IU/h). LVP, AOP, LVdp/dt and heart rate were recorded, MV02 was calculated by the computer (Bretschneider’s equation). Myocardial perfusion was measured after 90 min. of occlusion (tracer microspheres). M VO2 was comparable during both occlusion periods. CO (dye dilution technique) was 1,38±0,2 during CA-occlusion and 1,71±0,3 1/min. during TA-occlusion (p<0,01). In the non ischemic myocardium subepicardial and subendocardial perfusion was of equal value in both perfusion areas. Coronary ligation reduced flow drastically in the CA-region collateral flow (CF) in subendocardium was 11,8 ± 8 and 31,4 ± 12 ml/min.x100 g in the subepicardium. In The TA-region CF in the subendocardjum was 12,6 ± 5 and in the subepicardium 27,8 ± 14 ml/min.x100 g. CF was in the subendocardium significantly lower than in subepicardium in both perfusion areas (p<0,01). The present results show that CF in the ischemic myocardium cannot be modified by fibrinolysis. SK did not redistribute flow from subepicardium to subendocardium.

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Collateral flow velocity alterations in the supply and receiving coronary arteries during angioplasty for total coronary occlusion

Catheterization and Cardiovascular Diagnosis ◽

10.1002/ccd.1810340420 ◽

1995 ◽

Vol 34 (2) ◽

pp. 167-174 ◽

Cited By ~ 7

Author(s):

Morton J. Kern ◽

Jan J. Piek ◽

Frank V. Aguirre ◽

Richard G. Bach ◽

Eugene A. Caracciolo ◽

...

Keyword(s):

Flow Velocity ◽

Coronary Arteries ◽

Coronary Occlusion ◽

Collateral Flow

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Assessment of Coronary Arteries with Total Study Time of Less than 30 Minutes by Using Whole-Heart Coronary MR Angiography

Radiology ◽

10.1148/radiol.2371040830 ◽

2005 ◽

Vol 237 (1) ◽

pp. 316-321 ◽

Cited By ~ 159

Author(s):

Hajime Sakuma ◽

Yasutaka Ichikawa ◽

Naohisa Suzawa ◽

Tadanori Hirano ◽

Katsutoshi Makino ◽

...

Keyword(s):

Coronary Arteries ◽

Mr Angiography ◽

Study Time ◽

Whole Heart ◽

Coronary Mr Angiography

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Catecholamines and β-Adrenergic Receptors in the Non-ischemic Myocardium After Coronary Occlusion

Catecholamines and the Heart ◽

10.1007/978-3-642-68321-3_8 ◽

1981 ◽

pp. 72-91 ◽

Cited By ~ 1

Author(s):

G. Baumann ◽

G. Riess ◽

S. B. Felix ◽

W. D. Erhardt ◽

U. Loher ◽

...

Keyword(s):

Adrenergic Receptors ◽

Coronary Occlusion ◽

Ischemic Myocardium ◽

Β Adrenergic Receptors

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Assessment of Left Atrial Work During Acute Coronary Occlusion

Ultrasound in Medicine & Biology ◽

10.1016/j.ultrasmedbio.2018.11.008 ◽

2019 ◽

Vol 45 (3) ◽

pp. 749-757

Author(s):

Katsuji Inoue ◽

Toshihiko Asanuma ◽

Kasumi Masuda ◽

Daisuke Sakurai ◽

Takafumi Okura ◽

...

Keyword(s):

Left Atrial ◽

Coronary Occlusion ◽

Acute Coronary Occlusion

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Influence of neutrophil depletion on myocardial function and flow after reversible ischemia

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1989.256.2.h341 ◽

1989 ◽

Vol 256 (2) ◽

pp. H341-H351 ◽

Cited By ~ 4

Author(s):

P. G. O'Neill ◽

M. L. Charlat ◽

L. H. Michael ◽

R. Roberts ◽

R. Bolli

Keyword(s):

Polymorphonuclear Leukocytes ◽

Coronary Occlusion ◽

Critical Factor ◽

Wall Thickening ◽

Collateral Flow ◽

Vascular Abnormalities ◽

Reversible Ischemia ◽

Neutrophil Depletion ◽

Mediate Cell

We explored the role of polymorphonuclear leukocytes (PMN) in the genesis of contractile dysfunction (myocardial "stunning") and of vascular abnormalities after reversible ischemia. Open-chest dogs underwent a 15-min coronary occlusion and 4 h of reperfusion (REP); treated animals (n = 16) received intravenous goat antiserum against canine PMN, whereas controls received nonimmune goat serum (n = 10) or saline (n = 15). In treated dogs, the average blood PMN levels were 10% of those in saline controls. During ischemia, collateral flow tended to be higher, and paradoxical systolic wall thinning tended to be less in neutropenic dogs, but despite this, recovery of wall thickening after REP was not enhanced in these animals. Similarly, arrhythmias during ischemia or REP did not differ among the three groups. Four hours after REP, both resting and minimal coronary resistance (the latter assessed by adenosine infusion) were higher in the stunned compared with the nonischemic myocardium; these vascular derangements, however, were similar in all three groups. Thus profound neutropenia failed to attenuate mechanical dysfunction, to reduce arrhythmias, and to prevent vascular abnormalities after a 15-min coronary occlusion. Although previous studies have suggested that neutrophils mediate cell death during prolonged ischemia, the present findings suggest that PMN do not contribute importantly to the damage associated with brief, reversible ischemia. The duration of flow reduction may be a critical factor determining whether PMN exacerbate ischemic injury.

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Effects of time on volume and distribution of coronary collateral flow

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1976.230.2.279 ◽

1976 ◽

Vol 230 (2) ◽

pp. 279-285 ◽

Cited By ~ 40

Author(s):

ML Marcus ◽

RE Kerber ◽

J Ehrhardt ◽

FM Abboud

Keyword(s):

Blood Flow ◽

Vascular Resistance ◽

Coronary Occlusion ◽

Marked Decrease ◽

Relative Proportion ◽

Collateral Flow ◽

Coronary Vascular Resistance ◽

Collateral Blood Flow ◽

Coronary Collateral Flow ◽

Hemodynamic Measurements

Changes in the volume and distribution of collateral blood flow were studied during the 1st h after coronary occlusion in nine open-chest dogs. Labeled microspheres (7-10 mum) were injected into the left atrium prior to and 20 s, 5 min, and 60 min after acute occlusion of the midcircumflex coronary artery so that myocardial perfusion to small segments of the entire left ventricle could be measured. The segmental perfusions were classified as normally perfused, severely hypoperfused, moderately hypoperfused, and borderline hypoperfused. Standard hemodynamic measurements were obtained and relative coronary vascular resistance to the normally perfused and hypoperfused zones was calculated. The principal conclusions of the study are as follows: 1) during the 1st h after coronary occlusion the collateral flow to the hypoperfused myocardium increases substantially; 2) the increase in collateral flow is distributed fairly evenly to various hypoperfused zones and is associated with a marked decrease in coronary vascular resistance; and 3) as a result of this influx in collateral flow the size of the hypoperfused area decreases and the relative proportion of severely hypoperfused segments within the hypoperfused area decreases.

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