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Growth factors in the collateral circulation of chronic total coronary occlusions: relation to duration of occlusion and collateral function.

BACKGROUND: Despite extensive animal experimental evidence, there are few data on the relation of growth factors and collateral function in humans. METHODS AND RESULTS: In 104 patients with a chronic total coronary occlusion (CTO; >2 weeks' duration), collateral function was assessed invasively during recanalization by intracoronary Doppler and pressure recordings. A collateral resistance index, R(Coll), was calculated. Blood samples were drawn from the distal coronary bed supplied by the collaterals and from the aortic root to measure basic fibroblast growth factor (bFGF), monocytic chemotactic protein-1 (MCP-1), transforming growth factor-beta (TGF-beta), placenta growth factor (PlGF), and tumor necrosis factor-alpha (TNF-alpha). The bFGF concentration in the collateralized artery was higher than in the aortic root (34+/-20 versus 18+/-14 pg/mL; P<0.001). bFGF was highest in recent occlusions (2 to 12 weeks) with the highest R(Coll). Higher collateral concentrations were also observed for MCP-1, TGF-beta, and PlGF, but without a close relation to the duration of occlusion. TNF-alpha was not increased in collaterals compared with the systemic circulation. MCP-1, PlGF, and TGF-beta were significantly increased in small collaterals with the highest shear stress. Diabetic patients had lower bFGF and higher MCP-1 levels than nondiabetics. CONCLUSIONS: In CTOs, the continuous release of bFGF into collaterals showed a close relation to the duration of occlusion and collateral function, which underscores its therapeutic potential. Other factors influencing growth factor release appeared to be shear stress for MCP-1, TGF-beta, and PlGF and the presence of diabetes.

Aged↗

The development and enhancement of the collateral circulation in an animal model of lower limb ischaemia.

In an animal model of hind limb ischemia we documented the levels of endogenous basic fibroblast growth factor (bFGF) in control and ischaemic hind limbs, and evaluated the response to the administration of exogenous recombinant bFGF and heparin. Variations in this model were tested for their ability to alter the development of the collateral circulation. Recovery after acute arterial occlusion was significantly delayed by immediate bilateral mirror-image arterial ligations, when compared with either unilateral arterial ligation or delayed contralateral ligations performed after 2 months. If the major veins were also occluded all limbs developed gangrene, tissue loss and a marked delay in the recovery of blood flow, while none of the animals with unilateral arterial ligations developed gangrene. This indicates that the recovery in blood flow during the acute phase in this model is dependent on collateral vessels from the contralateral iliac artery and that major venous occlusion impedes the development of collateral vessels. Lumbar sympathectomy did not alter the recovery of blood flow after arterial occlusion, suggesting that collateral blood flow is not significantly influenced by autonomic neural supply. Following arterial occlusion there was a ten-fold increase in the levels of endogenous bFGF in all ischaemic muscle groups. Intramuscular implantation of bFGF in heparin-sepharose pellets at the time of arterial ligation markedly enhanced the blood flow for 3 weeks compared with untreated ischaemic limbs. A further increment in blood flow occurred if an additional dose of bFGF was administered 4 weeks after ligation.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Endotoxin-induced liver necrosis and intravascular coagulation in rats enhanced by portacaval collateral circulation.

The effects of intravenously administered endotoxin on the hepatic and systemic circulation as well as on the coagulation system were evaluated in normal rats (n = 26), in rats with experimental portal hypertension (n = 15), and in rats with portacaval anastomosis (n = 22). Endotoxin (1-5 mg/kg) in the normal rat leads to a prompt increase of transaminase activity and to a hyperdynamic circulation with a consequent increase in the total hepatic blood flow. In a later phase (6 h postoperatively) the hepatic artery dilated with a consequent hepatic arterial hyperperfusion. The coagulation system was affected with signs of consumption coagulopathy. In the rats with portal hypertension and portacaval collaterals as well as in those with portacaval anastomosis, the endotoxin injection resulted in acute liver necrosis within 12 to 15 hours. The hepatic artery became overdilated with a cardiac output fraction of 25% (normal 5-5%). Blood extravasates and thrombi, rich in fibrin, were detected in the liver. It is suggested that this exaggeration of the endotoxin effect was due to an impaired clearance function of the reticuloendothelial system, probably as consequence of portacaval collateral circulation. It is concluded that endotoxins (1) damage the liver even in a normal organism; (2) are potent to induce acute liver necrosis, if the reticuloendothelial system is altered; (3) have to be taken into consideration as contribution to the pathogenesis of acute as well as chronic liver diseases.

Alanine Transaminase↗

Collateral circulation in patients with unstable angina.

Coronary collaterals were evaluated in 218 consecutive catheterized patients with unstable angina (defined as ischemic cardiac pain at rest associated with transient electrocardiographic changes). Collaterals were present in 106 patients (49 percent). The presence of collaterals correlated with the extent and severity of the coronary artery disease but not with age, sex, or risk factors. Among patients with comparable severity of narrowings, the presence of collaterals did not appear to protect against abnormal wall motion or pathologic Q waves on the ECG. In patients with single vessel disease, collaterals also did not appear to protect against transient ST segment evaluation during ischemia.

Age Factors↗

[Pulmonary collateral circulation in lung cancer: a case of error in the measurement of cardiac output with dyes].

In a series of 40 cases of lung cancer, we recorded arterial dilution curves before and after unilateral occlusion of the pulmonary artery (on the pathologic side) following injection of dye into the pulmonary arterial trunk ("arterial curves") and in the capillary wedge position ("capillary curves"). In one case, a large pulmonary collateral circulation (PCC) is obvious, i.e., the dilution curve shows the characteristic shape of an early recirculation before and a normal shape after occlusion. In three cases, the PCC is likely to exist for: 1) decreasing of the capillary curves is abnormally slow during control; 2) transit time of capillary curves is obviously longer during control; 3) the surface under the arterial curve is 9 to 20 % larger during control than during occlusion. This surface undoubtly corresponds to the first dye circulation during pulmonary artery occlusion while, during control, it is increased by the PCC inspite of the exponential shape of the decreasing slope. Therefore the dye dilution method cannot be used to calculate precisely the PCC flow. Practically, in lung cancer measurements of the cardiac flow by dye dilution curves is erroneous about once out of 10 times. This conclusion can be extended to other lung diseases where a PCC may develop.

Adult↗

Effects of local MCP-1 protein therapy on the development of the collateral circulation and atherosclerosis in Watanabe hyperlipidemic rabbits.

OBJECTIVE: The objective of our study was to quantify the arteriogenic potency of Monocyte Chemoattractant Protein-1 (MCP-1) under hyperlipidemic conditions. Additionally, we aimed to determine the effects of locally applied MCP-1 on systemic serum lipid levels as well as on atherosclerosis. METHODS: A total of sixty-four Watanabe rabbits was treated with either low dose MCP-1 (1 microg/kg/week), high dose MCP-1 (3.3 microg/kg/week) or PBS as a control substance. Substances were applied directly into the collateral circulation via an osmotic minipump with the catheter placed in the proximal stump of the ligated femoral artery. Either 1 week or 6 months after initiation of the treatment X-ray angiography was performed as well as measurements of collateral conductance using fluorescent microspheres. The extent of atherosclerosis was quantified in whole aortas using Sudan IV staining. RESULTS: One week after ligation of the femoral artery a significant increase in collateral conductance was observed in animals treated with high dose MCP-1 (control: 2.2+/-0.8 ml/min/100 mmHg vs. MCP-1 high dose: 8.9+/-2.0 ml/min/100 mmHg, P<0.05). Six months after femoral artery ligation no differences were found between the treated and the control group (PBS; 44.9+/-11.6 ml/min/100 mmHg, MCP-1; 47.8+/-11.5 ml/min/100 mmHg, P=NS). No influence was found on serum lipids or on the development of atherosclerosis in the present model. CONCLUSION: MCP-1 accelerates arteriogenesis upon femoral artery ligation under hyperlipidemic conditions. Six months after treatment these pro-arteriogenic effects of MCP-1 can no longer be observed. The present data do not show an effect of local MCP-1 treatment on serum lipids or on atherosclerosis. It should be noted however that a high standard deviation was observed for the data on atherosclerotic surface area, necessitating additional experiments in a different model of atherosclerosis.

Animals↗

An experimental hemodynamic study of the pelvic collateral circulation.

Iliac arteries were occluded in adult mongrel dogs to investigate pelvic hemodynamics. When the unilateral common iliac artery was occluded, the blood flow making a "stopover" within the pelvis was found to be significantly less than that of anatomical hemodynamics even under a resting condition. The blood flow decreased more significantly under exercise loading than under a resting condition, which demonstrates the presence of the "steal" phenomenon. This only occurs in the collateral circulation in the pelvis formed by two arterial systems which are related in a series. In deciding the appropriacy of reconstruction for the internal iliac artery in patients with aorto-iliac occlusive disease, this "steal" phenomenon should be kept in mind. In most cases, ischemic symptoms in pelvic organs may be due to a simple decrease of the blood flow supplied to the pelvis, or due to the "steal" phenomenon. If the pelvic region is in the state of ischemia owing to the "steal" phenomenon, reconstruction of the blood vessels flowing into the pelvis is not required.

Animals↗

[The collateral circulations of the spermatic veins (author's transl)].

The frequency and appearance of anastomoses between the spermatic veins and the inferior vena cava and portal vein, are analyzed in a series of 171 patients examined by retrograde spermatic phlebography. Spermatocaval anastomoses are divided into those that occur above the scrotum: direct (spermatocaval and iliospermatic) and indirect (perivertebral and ureteric); and those seen at the level of the scrotum (with the scrotal veins, veins of the vas deferens, and those from the contralateral scrotal area). Spermatoportal anastomoses are frequent but difficult to confirm because of the existence of proximal valves. Three cases are also reported which give examples where the spermatic vein played an important part in the collateral circulation (inferior vena cava thrombosis, left renal vein thrombosis, portal hypertension).

Collateral Circulation↗

Embolization via collateral circulation during carotid stenting with the distal balloon protection system.

PURPOSE: To describe a potential route for embolization to the middle cerebral artery (MCA) during carotid stenting with the distal balloon protection system. CASE REPORT: An 82-year-old man with symptomatic severe carotid artery stenosis underwent elective carotid stenting with distal-balloon protection. Despite complete occlusion of the distal internal carotid artery, frequent emboli were detected in the ipsilateral MCA by transcranial Doppler (TCD) during the procedure. Intracranial angiography, performed during the distal-balloon protection, revealed filling of the MCA through collaterals from the ipsilateral external carotid artery. The procedure was successfully completed without complications. The patient remains asymptomatic at 6 months. CONCLUSIONS: During carotid stenting with distal-balloon protection, asymptomatic embolization into the ipsilateral MCA may occur through collateral circulation. The clinical significance of these emboli is uncertain.

Aged↗

[Collateral circulation after the division of the common hepatic artery--experimental study in dogs].

The influence of division of the common hepatic artery (CHA) was studied using dogs, by measuring the blood flow of the proper hepatic artery (PHA) by an electromagnetic flowmeter, and tissue blood flow of the liver and the gallbladder by the H2 gas clearance method. The results expressed as relative values (value before the division of CHA = 1.0) were as follows. 1) PHA blood flow decreased to 0.40 +/- 0.18 (n = 14) after the division of CHA. 2) After the division of CHA, tissue blood flow of the liver decreased to 0.61 +/- 0.16 (n = 27), and tissue blood flow of the gallbladder, to 0.51 +/- 0.16 (n = 40). After additional occlusion of the gastroduodenal artery, these values were 0.51 +/- 0.16 and 0.23 +/- 0.13, respectively. 3) On the seventh day after CHA division, tissue blood flow of the gallbladder recovered to 0.84 +/- 0.50. 4) Necrosis of the gallbladder, which was mostly partial was found in 20% of the experimental dogs at autopsy. These results showed that there is effective arterial collateral circulation after division of the CHA, which makes Appleby's operation practicable. However, considering the degree of ischemia observed in the gallbladder, preservation of collaterals during Appleby's operation will be essential for the prevention of necrosis of the gallbladder.

Animals↗

Paraumbilical venous collateral circulations: color Doppler ultrasound features.

Using Color Doppler ultrasonography to trace the dilated paraumbilical vein to its connection with systemic veins in 27 patients, we have found four major pathways: In type 1 (63%), the vein connected with the external iliac vein via the inferior epigastric vein. In type 2 (3.7%), the vein connected with the saphenous vein via the superficial epigastric vein. In type 3 (22.2%), the vein connected with the internal thoracic vein via the superior epigastric vein. Type 4 (11.1%) is a combination of types 1 and 2. A frank caput medusa was not seen, but occult caput medusa were seen in two patients. Turbulent flow was seen at the junction between inferior epigastric and external iliac veins, paraumbilical and superficial epigastric veins, and superficial epigastric and saphenous veins in some patients. Color Doppler ultrasonography is a convenient, noninvasive method for determining the course and associated hemodynamic changes in the paraumbilical collateral circulation.

Adult↗

[Non-invasive evaluation of the greater and collateral circulation in arterial occlusive diseases of the lower extremities].

A method of dosed compressive loads with a simultaneous registration of linear blood flow rate in the femoral artery was used in 32 healthy people and 30 patients with different localization of atherosclerotic process in major vessels with the help of an ultrasound apparatus of Bi-Doppler class and specific blood filling of lower extremities by the method of tetrapolar rheography. It was shown that most sensitive and objective index for the assessment of major and collateral blood circulation is a decrease or absence of the retrograde blood flow.

Aorta, Abdominal↗

Parietal centripetal and centrifugal thickening neovascularization in the descending anterior coronary artery. Possible relations with the problem of collateral circulation.

Left coronary arteries of 30 human hearts, obtained at autopsy, were injected with contrast medium. A control group was formed from anterior descending coronary arteries free of atherosclerosis and a study group from anterior descending coronary arteries with areas of atherosclerotic injury. The following differences in the two groups were noted. The control group did not show successfully injected vessels in intima and media, while cases with atherosclerotic injury have them; the number of injected vessels in presence of atherosclerotic injury was three times greater than in healthy coronary arteries; there was a decreasing gradient from outside to in, in the number of injected vessels in both groups; and finally in atherosclerotic vessels we noted a lack of balance between parietal thickening and the residual lumen (conspicuous thickening was accompanied by a small reduction in the lumen). We interpret centrifugal thickening as a possible compensatory mechanism in the major branches for an inadequate canalization of vessel, and suggest possible formation, of coronary collateral circulation from vasa vasorum by a process of neovascularization.

Adult↗

Arterial vascularization of the human moderator band: an analysis of this structure's role as a collateral circulation route.

In the human heart, the moderator band, or trabecula septomarginalis, is a muscle column that courses inferiorly from the right portion of the interventricular septum to the base of the anterior papillary muscle of the right ventricle This muscular structure is crossed by one or more arteries, which come from the anterior interventricular artery and perfuses the anterior papillary muscle of the right ventricle. In order to clarify the arterial supply of this muscle column, we studied 28 adult hearts, free of any signs of coronary disorder. The path of the moderator band artery was followed by means of microdissection, and we studied the source, course, and interconnections made with other arteries. We observed that the source of the moderator band artery lies in the first three anterior septal arteries, most often in the second one. In relation to the short axis of the heart, the artery of the moderator band can either follow a horizontal path to the septal papillary muscle of the right ventricle or an oblique route to the moderator band, depending on the position of its source. In all the hearts studied, the moderator band artery made anastomotic connections at the base of the anterior papillary muscle of the right ventricle with various branches of the right coronary artery, which means that it can play a key role in collateral circulation following obstruction of the epicardium coronary arteries.

Adult↗