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Results for “Collateral Circulation”

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PubMed1990

[Transient abnormal Q waves under acute myocardial infarction in patients with pneumoconiosis].

Abnormal Q waves have been generally considered to be one of the most reliable indicators of permanent myocardial cell death, namely myocardial infarction. Pathological and experimental studies also support this concept. However, some cases of abnormal Q waves disappearing after myocardial infarction have been reported. Recently, we observed acute myocardial infarction with pneumoconiosis. In this case, a patient with abnormal Q waves appeared within 24 hours after the onset of acute myocardial infarction. But, thirteen days later, these abnormal Q waves disappeared on the surface twelve-lead ECG. The precise mechanism for regression or disappearance of abnormal Q waves is not yet well known. Several studies pointed out a relation of this phenomenon to myocardial collateral circulation under ischemia. And, Nonkin et al reported that, patients with chronic lung disease such like pneumoconiosis, had high incidence of collateral circulation to the myocardium. This was due to chronic hypoxic conditions. In our case, cineangiographic study could not be performed, but disappearance of abnormal Q wave (so called Transient abnormal Q waves), following acute myocardial infarction may be related to the presence of chronic lung disease.

Aged↗

PubMed2002

The preservation and reconstruction of cerebral veins and sinuses.

Although cerebral veins and venous sinuses are very important to the neurosurgeon, they have received adequate attention only recently. The consequences of cerebral venous occlusion are well known. When the venous outflow is compromised due to a lack of adequate collateral circulation, venous infarction follows, with swelling, haemorrhage and neuronal death. The clinical consequences will depend upon the region of involvement of the brain and the site of the infarcted tissue. The symptoms may include seizures, hemiplegia, aphasia, coma and death. Similarly, the consequences of cerebral venous sinus occlusion depend upon the availability of collateral circulation. When such collaterals are not available, papilledema and visual loss and a pseudotumour cerebri syndrome are observed in milder cases, whereas, severe diffuse brain swelling, coma and death may be observed in severe cases. Acute venous or venous sinus occlusion is potentially very dangerous, whereas slow and chronic venous or venous sinus occlusion is better tolerated. Even in such patients, some neurological manifestations may follow, when the collaterals are poor.

Adult↗

PubMed1985

[Anatomy and surveillance of key sites and collateral pathways in arteriopathies of the lower extermities].

Key sites to be followed up are defined as a function of initial explorations of lesions in operated or unoperated arterial disease of the lower limb. Details of these key sites were obtained from pathologic examination of collateral vessel networks. Precise studies were conducted of the collateral circulation after infrarenal aortic obliterations, and femoral and tibial artery occlusions. Prediction of the ischemic risk and therefore of prognosis, and choice of therapy, can be obtained only by a detailed study of the reentry value through the bias of this collateral circulation.

Arterial Occlusive Diseases↗

PubMed2000

Bidirectional function of coronary collateral channels in humans.

To investigate the bidirectional functional adequacy of collateral perfusion, we performed percutaneous transluminal coronary angioplasty (PTCA) on highly stenosed or occluded coronary arteries visualized by the collateral circulation,which were fed by the contralateral coronary artery with severe stenosis. After successful PTCA in all three patients, the contralateral artery was reversely filled by good collateral circulation originating from the dilated coronary artery. These findings indicated that dilation of the receiving coronary artery reversed the pressure gradient across the collateral network, establishing collateral flow in the opposite direction. It was concluded that human collateral channels serve as a bidirectionally functional conduit.

Aged↗

PubMedDate not supplied

[Paget-Schroetter disease: clinical and therapeutic considerations].

A case of subclavian-axillary vein thrombosis prompted us to review the recent literature on the subject. Paget-Shroetter disease is an uncommon disease, which is still associated with high early and late morbidity rates and the prevention of which requires early diagnosis and treatment. The importance of trauma (in the form of physical strain) in determining the symptoms of the disease is universally accepted. We observed subclavian-axillary vein thrombosis in a young 22-year-old athlete who complained of unexpected onset of pain in the left armpit, spreading to the arm and to the shoulder on the same side, functional impotence of the upper arm and swelling of the hand and forearm, and engorgement of the vessels in the arm, shoulder and clavipectoral region, which in the course of time developed the characteristics of a collateral circulation. The patient underwent phlebography which documented lack of opacification of the axillo-subclavian axis and showed the presence of a collateral circulation with dilation of the vein of the shoulder and arm. We first attempted to dissolve the thrombus by locoregional infusion of urochinase and later started anticoagulative therapy with an intravenous infusion of heparin (10,000 IU/h after a bolus of 500 units). Because of the poor result of thrombolysis and anticoagulative therapy and the progressive worsening of the disease, the patient underwent surgery to restore the continuity of the venous axis. The surgical procedure was performed through a skin incision along the upper edge of the collar-bone. This was dissected and the two stumps were well separated to allow a clear view of the subclavian vein. Phlebotomy, thrombectomy and reconstruction of the venous axis with an expanded polytetrafluoroethylene patch were performed. The postoperative course was uneventful and the patient underwent phlebography again on postoperative day 8, which demonstrated complete patency of the subclavian vein, and was discharged on postoperative day 20 on oral anticoagulative therapy.

Administration, Oral↗

PubMed1999

Subclavian steal syndrome and flow-related aneurysm. Another reason to treat.

A 48-year-old woman presented with a symptomatic right subclavian steal syndrome due to proximal subclavian artery stenosis. Anatomically the innominate artery was absent. Collateral circulation followed the vertebro-vertebral pathway with reversal of blood flow in the ipsilateral vertebral artery. There was also multiple dilated intervertebral collaterals and an associated saccular aneurysm on one of them. Surgical carotid-subclavian transposition permitted relief of clinical symptoms, disappearance of collateral circulation and subtotal regression of the aneurysm. This spontaneous evolution confirmed the role of high-flow in the pathogenesis of some aneurysms and the habitually good prognosis of flow-related aneurysms with correction of the cause. Arteriography still appears essential in diagnosis, pretherapeutic assessment and sometimes post-treatment evaluation in subclavian steal syndrome.

Aneurysm↗

PubMed1992

Significance of preinfarction angina for preservation of left ventricular function in acute myocardial infarction.

The effect of preinfarction angina on the preservation of left ventricular function was evaluated with the use of cineventriculography in 37 patients who had either total or subtotal occlusion of the proximal left anterior descending coronary artery during the convalescent period of myocardial infarction. In 15 patients who had preinfarction angina more than 1 week before the onset of acute myocardial infarction (group A), the global left ventricular ejection fraction was 54 +/- 3% (SEM) and regional wall motion in the infarct area was 10 +/- 3%. In 10 patients who had preinfarction angina occurred within 1 week before the onset of acute myocardial infarction (group B), the left ventricular ejection fraction and regional wall motion in the infarct area were 42 +/- 3% and 1 +/- 2%, respectively. In 12 patients without preinfarction angina (group C), the left ventricular ejection fraction and regional wall motion in the infarct area were 38 +/- 3% and -1 +/- 2%, respectively. In groups B and C, both the left ventricular ejection fraction and regional wall motion in the infarct area were lower than those in group A (p less than 0.05). The collateral circulation at the onset of acute myocardial infarction was better in group A compared with groups B and C (p less than 0.05). Thus the collateral circulation, promoted by repetitive anginal episodes indicative of myocardial ischemia, causes the preservation of myocardial function.

Angina Pectoris↗

PubMed1997

Delayed stimulation of the latissimus dorsi may result in disuse atrophy.

BACKGROUND: The latissimus dorsi is usually left unstimulated for 2 weeks after cardiomyoplasty to allow the muscle to recover from the loss of the collateral circulation. To determine whether the 2-week delay may cause muscle atrophy, we randomized 15 mongrel dogs to a control group or a disuse atrophy group. METHODS: The collateral circulation to the latissimus dorsi was ligated in all animals before cardiomyoplasty to reduce the risk of ischemic injury to the muscle during mobilization. Two weeks after collateral ligation, the atrophy group had the tendinous attachment of the latissimus dorsi severed and then 2 weeks later underwent cardiomyoplasty. The control group had a 2-week delay after collateral ligation followed by cardiomyoplasty. Biopsies were performed before collateral ligation and before cardiomyoplasty. After heart failure was induced, hemodynamic function was assessed during synchronized contraction of the latissimus dorsi by measuring the maximum systolic elastance, stroke volume, preload recruitable stroke work index, and diastolic compliance. RESULTS: Comparison of muscle morphology between the two groups demonstrated the presence of muscle atrophy in those animals that had been randomized to the atrophy protocol. During synchronized contraction of the latissimus dorsi, there was no significant increase in maximum systolic elastance in either group. However, both stroke volume and pulmonary recruitable stroke work index were significantly higher in the control animals during assisted beats. The left ventricle was less compliant in the atrophy group, suggesting that muscle atrophy had adversely affected diastolic function. CONCLUSIONS: Delayed electrical stimulation of the latissimus dorsi may result in atrophy and loss of function.

Animals↗

PubMed1990

Studies of collateral perfusion to canine middle cerebral artery territory.

Previous studies of intracranial collateral circulation have not distinguished between true "collateral" blood flow (flow to a region that occurs only when a primary artery is occluded) and "overlap" flow (flow to a region that is present under both normal and demand conditions). These experiments had three purposes: 1) to identify tissues that were truly collateral dependent, 2) to determine potential for true collateral flow in the absence of overlap flow, and 3) to determine whether an anatomical basis for overlap flow could be demonstrated. Branches (700-900 microns) of the dog middle cerebral artery (MCA) were perfused with autologous blood. The perfused region, which was the area at risk, was identified by intravenous injection of neutral red dye. Microspheres were used to measure regional cerebral blood flow (rCBF). Overlap flow was determined by perfusion of the artery with microsphere-free blood. True collateral flow (total rCBF minus overlap flow) was determined by analysis of rCBF to the risk area after cessation of vessel perfusion. Most of the risk area had substantial levels of overlap flow (about one-third of base line). In the center of the area at risk, the true collateral-dependent area was identified [mean overlap flow 4 +/- 1 (mean +/- SE) ml.min-1.100 g-1], which had high levels of perfusion from collateral vessels (102 +/- 14) within 30 s of vascular occlusion. Microfil injection into two adjacent MCA branches showed discrete borders between vascular territories, with no overlapping vessels.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1997

Growth factors as a potential new treatment for ischemic heart disease.

Growth factors such as fibroblast growth factor (FGF) and vascular endothelial growth factor (VEGF) exert important effects on endothelial cells in vitro and in vivo. This article reviews the effect of these two growth factors on endothelial dysfunction in various animal models of vascular disease: (1) collateral circulation supplying an ischemic territory, (2) balloon injury, and (3) diet-induced experimental atherosclerosis. Endothelial dysfunction may limit the beneficial effects of collateral vessels on tissue perfusion. Administration of VEGF or basic FGF (bFGF) augments collateral development in different models of hindlimb ischemia by enhancing neovascularity and by facilitating the recovery of endothelial function in the collateral circulation. Similarly, studies performed after balloon angioplasty have demonstrated abnormal responses of previously dilated sites to endothelium-dependent agonists. Administration of VEGF or bFGF increases endothelial regrowth and normalizes endothelium-dependent responses after experimental angioplasty. Finally, endothelium-dependent relaxation is impaired in diet-induced experimental atherosclerosis. It was recently demonstrated that hypercholesterolemic rabbits treated with bFGF had significantly better endothelium-dependent responses than those not treated with bFGF. These results show that in vivo administration of the endothelial cell growth factors VEGF and bFGF leads to significant improvement in endothelium-dependent responses and supports the concept of using these growth factors as a new therapeutic strategy for patients with vascular diseases.

Animals↗

PubMed2003

Paget-Schroetter syndrome therapy: failure of intravenous stents.

BACKGROUND: The purpose of this study is to show that intravenous stents (IS) are contraindicated in patients with thrombosis of the axillary-subclavian vein (Paget-Schroetter syndrome). METHODS: Twenty-two patients had IS placed after balloon dilatation of the venous compression in the thoracic outlet. Each of the patients receiving IS had the diagnosis made less than 6 weeks after vein occlusion, previous thrombolytic therapy, and poststent anticoagulants. (All were performed in outside hospitals. In no case was surgical decompression of the "externally constricted venous tunnel" performed.) The 22 patients receiving IS were compared with a similar group of 384 patients seen less than 6 weeks after thrombosis who were treated with "optimal therapy," ie, thrombolysis and prompt transaxillary resection of the first rib with venous tunnel decompression. RESULTS: All 22 patients with IS reoccluded their axillary-subclavian vein from 1 day to 6 weeks after insertion. All were retreated with thrombolytic therapy and first rib resection. Ten remained patent and 7 remained occluded but developed adequate collateral circulation. All 17 were asymptomatic. Five remained occluded with minimal collateral circulation. Attempts were made to reopen them a third time. All 5 are receiving long-term anticoagulants. In contrast the 384 patients managed with optimal therapy were significantly improved without retreatment or anticoagulants. CONCLUSIONS: From our study, there is no indication for use of IS in patients with Paget-Schroetter syndrome; in fact, from our experience it is contraindicated when compared with the optimal therapy group. Other authors corroborate this conclusion in recent review articles.

Adolescent↗

PubMed1990

[Ischemic cerebrovascular complication in tuberculous meningitis; a case of Fröhlich syndrome and hemiparesis].

A 34-year-old man came to our hospital with an episode of focal convulsion of the left arm. He had suffered from tuberculous meningitis in childhood and developed left hemiparesis and Fröhlich syndrome as sequelae. CT scan showed a calcified mass in the suprasellar cistern and a low density area suggestive of cerebral infarction in the right anterior cerebral artery distribution. The left carotid angiograms showed severe stenosis of the left internal carotid artery in the supra-clinoid segment and occlusion of the proximal middle and anterior cerebral arteries with development of moyamoya vessels as collateral circulation. The right carotid angiograms showed similar findings with less collateral circulation. At surgery, the anterior part of the Willis ring was found embedded in the suprasellar calcified granuloma. Recognition of cerebrovascular complication in tuberculous meningitis is important and an early modification of the therapy may improve the outcome.

Adult↗

PubMed2000

Age-dependent impairment of coronary collateral development in humans.

The purpose of this study was to evaluate whether age influences collateral development in patients with coronary artery disease. The extent of collateral development to the area perfused by the infarct-related artery was graded, depending on the degree of opacification of the occluded infarct-related artery. We evaluated the extent of collateral development using coronary cineangiography in 102 patients with an acutely occluded infarct-related coronary artery within 12 h after the onset of the first acute myocardial infarction, and who had a history of long-standing effort angina. Well-developed collateral circulation was observed in 54 (53%) of the patients. The patients were divided into two groups based on their age. The prevalence of well-developed collateral circulation in the younger group (< or = 64 years, n = 48) was 69% (33 of 48), being significantly (P = 0.003) higher than 39% (21 of 54) in the older group (> or = 65 years, n = 54). We conclude that in the presence of stimuli for collateral development i.e., long-standing effort angina accompanied by severe coronary stenosis, the age of patients is a key determinant of collateral development.

Adult↗

PubMed2001

The clinical significance of reverse redistribution in Tl201 cardiac SPET.

UNLABELLED: In an attempt to evaluate the clinical significance of reverse redistribution in Tl201 cardiac SPET, Tl201 SPET examinations included in the data base of our department have been retrospectively reviewed. PATIENTS: Six hundred ninety eight patients demonstrated the pattern of reverse redistribution. For 237 of these patients' cardiac catheterization data were also available. One hundred and six patients of these had a history of myocardial infarction while the rest of them were referred for angina symptoms. RESULTS: Catheterization showed that the infarction area was perfused by a stenosed but patent vessel in 79 of the 106 patients with a history of myocardial infarction (74.5%). Collateral circulation was evident in 21 of these 106 patients (19.8%). Only six patients (5.6%) showed a totally occluded vessel with no obvious evidence of collateral circulation. Of the 131 patients, with no myocardial infarction history, 14 (10.7%) had normal coronary vessels. The rest of the patients (89.3%) demonstrated stenotic vessels perfusing the same area where reverse redistribution was observed. Sixty-three of these patients have been reexamined after 9-36 months. On 15 of these patients (23.8%) the second scintigram showed ischemia in the same segments where reverse redistribution was initially detected. Another 17 of the above patients had a former scintigraphic examination that showed ischemia on the segments that currently demonstrated reverse redistribution. CONCLUSION: The results of the present retrospective study indicate that, in patients with known coronary disease, the pattern of reverse redistribution frequently indicates the ischemic area.

Adult↗

PubMed1979

Coronary arteriography in acute transmural myocardial infarction.

Coronary arteriography was performed 16 +/- 3 days (range 7 to 21 days) in 106 patients with acute transmural myocardial infarction (61 posterior infarct, 45 anterior infarct). Coronary arteriography was performed without serious complications. Only 44% of patients with anterior infarct had total occlusion of the left anterior descending artery while a significant stenosis of the vessel was observed in the others -27% had a single vessel disease, 49% had two lesions and 22% had three lesions; one patient had angiographically normal coronary arteries. Among the patients with posterior infarction, 21% had one vessel disease and double or triple lesions accounted for 39% of each. Sixty per cent of patients with anterior infarction and 45% with posterior infarction had no collateral vessels. In the others patients collateral circulation had a protective effect only in anterior infarction. Age has no effect on the distribution and number of lesions nor on the development of a collateral circulation. The location and severity of the lesions were not different in patients who presented with arrythmias and those who did not.

Acute Disease↗

PubMed1995

Quantification of recruitable coronary collateral blood flow in conscious humans and its potential to predict future ischemic events.

OBJECTIVES: The present study was designed to evaluate the applicability of a pressure-flow equation for quantitative calculation of recruitable collateral blood flow at coronary artery occlusion in conscious patients and to investigate the value of that index to predict future ischemic events. BACKGROUND: Recent experimental studies have indicated that recruitable collateral blood flow at coronary artery occlusion can be expressed as a fraction of normal maximal myocardial blood flow by simultaneous recordings of mean arterial, coronary wedge and central venous pressures, respectively. This index is called the pressure-derived fractional collateral flow and is independent of hemodynamic loading conditions. METHODS: In 120 patients undergoing elective coronary angioplasty, mean arterial, coronary wedge and central venous pressures were measured at balloon inflations of 2 min. All patients had a recent exercise electrocardiogram (ECG) with positive findings showing clearly distinguishable, reversible ECG abnormalities, enabling recognition of ischemia at balloon inflation. Fractional collateral blood flow at angioplasty was calculated by coronary wedge pressure minus central venous pressure divided by mean arterial pressure minus central venous pressure and correlated to the presence or absence of ischemia at balloon inflation. Ischemic events were monitored during a follow-up period of 6 to 22 months. RESULTS: In 90 of the 120 patients, ischemia was present at balloon inflation, and in 82 of these patients, fractional collateral blood flow was < or = 23%. By contrast, in 29 patients, no ischemia was present, and fractional collateral blood flow was > 24% in all 29. During the follow-up period, 16 patients had an ischemic event. Fifteen of these 16 patients were in the group with insufficient collateral flow (p < 0.05). CONCLUSIONS: To our knowledge, this study presents the first method for quantitative assessment of recruitable collateral blood flow in humans in the catheterization laboratory. Sufficient and insufficient collateral circulation can be reliably distinguished by this method. Use of this method can also help to provide more insight into the extent and behavior of the collateral circulation for investigational purposes and may have potential clinical implications.

Angina Pectoris↗

PubMed1991

Long-time inflation of the PTCA balloon.

For patients for whom the conventional percutaneous transluminal coronary angioplasty (PTCA) did not adequately improve stenosis, or sufficient angioplasty was impossible because of occurrence of dissection, we attempted using a long-time balloon inflation for more than 10 minutes. In order to allow the use of this balloon, we instituted an active rehabilitation program using a bicycle ergometer to promote the development of the collateral circulation up to the time of performing diagnostic angiography and PTCA, while attempting to use a perfusion balloon catheter for those patients not developing sufficient collateral circulation. Of the 134 patients undergoing PTCA, unsatisfactory angiographic results were obtained in 13 patients. Of these patients, long-time balloon inflation was performed in seven and primary success was achieved in six. From this study, we believe that the long-time balloon inflation in PTCA can improve the primary success rate and reduce postoperative complications.

Angina Pectoris↗

PubMed1997

Nitroglycerin-augmented 201T1 reinjection enhances detection of reversible myocardial hypoperfusion. A randomized, double-blind, parallel, placebo-controlled trial.

BACKGROUND: Recent observations suggest that administration of nitrates before 201Tl reinjection enhances the detection of reversible myocardial hypoperfusion. METHODS AND RESULTS: Ninety-six patients who underwent exercise-redistribution 201Tl single photon emission computed tomography (SPECT) and had persistent defects at 4-hour redistribution imaging were prospectively randomized into a double-blind protocol in which they received a reinjection of 201Tl (1.0 mCi) 5 minutes after either placebo or 0.8 mg sublingual nitroglycerin administration, followed by repeat SPECT imaging. Of the 69 patients who had coronary angiography, all except one had significant coronary stenoses. The overall extent of perfusion defect and the reversible component assessed by polar maps of the stress-redistribution images were similar in patients who received nitroglycerin or placebo. Among the 66 patients with persistent defects in the redistribution images, 58% of those receiving nitroglycerin showed improved reversibility after reinjection, compared with 33% of patients receiving placebo (P < .05). Among 68 patients with significant coronary stenoses, those who received nitroglycerin and had coronary collateral circulation were more likely to exhibit improved reversibility after reinjection than the remaining patients (50% versus 21%, P < .05). Moreover, the ratio of reversible to total defect in the vascular territories supplied by collaterals was > or = 0.50 after reinjection in 80% of patients who received nitroglycerin (n = 20) compared with 40% of the patients who received placebo (n = 15) (P < .05). CONCLUSIONS: Nitrate-augmented 201Tl reinjection significantly, albeit modestly, improves detection of defect reversibility, especially in patients with coronary collateral circulation.

Collateral Circulation↗