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PubMedDate not supplied

[Importance of the systemicopulmonary collateral arterial circulation in congenital cardiopathies].

This paper manifests the importance of the systemic-pulmonary collateral circulation in congenital heart diseases. It shows that through the angiographic and hemodynamic study you should recognize the number, origin, course, and size of each of these arteries because during the corrective surgical treatment of certain types of heart diseases, these arteries should be tied off to prevent cardiac overload during the procedure and to prevent intrapulmonary short circuits from left to right in the postoperative period. The knowledge of the central and peripheral pulmonary arteries is important and because of this it should be remembered that the area of the section of the pulmonary arteries, right to left, together should be at least the equivalent of half of the area of the section of the aorta in its diaphragmatic level, the diameter which permits an acceptable cardiac output after the intervention. If the arteries are adequate a plan of surgical intervention which permits the control of the collateral systemic-pulmonary great arteries should be drawn up.

Collateral Circulation↗
PubMed1989

Infarct size and the protection of ischemic myocardium in pig, dog and human.

To define whether recanalization after occlusion can reduce the myocardial infarct size, we compared the infarct size in 25 pig hearts without collateral circulation, 35 dog hearts with collateral circulation and 11 human autopsied hearts with coronary thrombolysis at 2 to 6 hours after the onset of acute myocardial infarction. The data showed that % infarct size in the risk area increased according to the duration of occlusion. In the pig, % infarct size was 80 +/- 9% in the recanalization after 1 hour occlusion and 96 +/- 2% in the recanalization after 2 hour occlusion. There was no significant difference between these and the permanent occlusion group (95 +/- 3%). In the dog, % infarct size was 35 +/- 31% in the recanalization after 4 hour occlusion and 59 +/- 27% in the permanent occlusion group. In human autopsied hearts, the infarct size was the same between the recanalization group (82 +/- 6%) and the permanent occlusion group (80 +/- 11%). The % infarct size in the recanalization groups was less than or the same as that in the hearts with permanent occlusion in dog, pig and human. Thus, it is concluded that, to reduce conclusively the infarct size, recanalization should be done within 1 hour after the occlusion in the hearts without collateral circulation and within 4 hours in the hearts with collateral circulation. So called reperfusion injury which means the greater expansion of the % infarct size than that in the permanent occlusion is not present.

Animals↗
PubMed1981

Left ventricular overload caused by collateral pulmonary circulation in chronic pneumopathies-myth or reality?

The collateral pulmonary blood flow was measured by the dye dilution method in four patients with chronic obstructive pulmonary disease, in 16 patients with diffuse pulmonary fibrosis, in 15 patients with pulmonary embolism, and in three patients with primary pulmonary hypertension. The authors found that collateral pulmonary circulation was small in the first two groups (0.3 % and 1.7% of the pulmonary blood flow, respectively), absent in primary pulmonary hypertension, and high (14.0% of pulmonary flow) in pulmonary embolism. The magnitude of the bronchopulmonary collateral circulation did not correlate with degree of precapillary pulmonary hypertension, left atrial pressure and left ventricular enddiastolic pressure. It seems that the bronchopulmonary collateral flow does not produce diastolic left ventricular overload in chronic pneumopathies.

Chronic Disease↗
PubMed2006

Functional assessment of the collateral-dependent circulation in chronic total coronary occlusion using transthoracic Doppler ultrasound and venous adenosine infusion.

The measurement of collateral flow reserve (CFR; the hyperemic/baseline collateral flow velocity ratio) in patients with chronic total coronary occlusion requires invasive and expensive techniques. Noninvasive transthoracic coronary Doppler echocardiography may be an alternative option. Fifty-one patients with chronic total coronary occlusion were evaluated by transthoracic coronary Doppler echocardiography and venous adenosine infusion to measure CFR in occluded coronary arteries (the left anterior descending artery in 44 patients and the artery supplying the posterior descending artery in 7 patients). CFR data were plotted against 3 angiographic parameters: (1) grade of the epicardial filling of the occluded artery (1=absent, 2=partial, 3=complete), (2) stenosis of the donor artery, and (3) the extent of coronary artery disease (vessels with >or=70% stenosis). Collateral flow was maintained at stress in 34 patients (CFR>or=1, range 1.0 to 2.2) but was withdrawn in 17 patients (CFR<1, range 0.25 to 0.90). CFR increased with the degree of angiographic collateral flow (grade 1: 0.73+/-0.29; grade 2: 1.16+/-0.31; grade 3: 1.34+/-0.49; F=5.31, p=0.008). A multivariate model of CFR prediction showed a direct relation with angiographic collateral grade and the number of diseased vessels and an inverse relation with stenosis of the donor artery. In conclusion, CFR measurement is feasible by transthoracic coronary Doppler echocardiography. One third of the patients with chronic total coronary occlusion had collateral flow withdrawal at stress, which occurs when collateral circulation is poor and when the donor artery is stenotic. CFR correlates with angiographic collateral grade and with the extent of coronary artery disease.

Adenosine↗
PubMed1989

Evaluation of the palmar circulation by pulse oximetry.

The usual method of substantiating collateral circulation of the hand is with Allen's test. We used the pulse-detecting capability of the pulse oximeter to assess the presence of collateral circulation of the hand. Thirty-one patients undergoing radial artery cannulation for intraoperative monitoring were evaluated before cannulation with a modified Allen's test and by pulse oximetry. After the collateral circulation of the hand was tested by the modified Allen's test, a pulse oximeter probe was placed on the index finger. Both radial and ulnar arteries were occluded until no perfusion was detected by the pulse oximeter. The test was repeated twice on each hand, once for each artery. The time to reperfusion after arterial release was recorded. Reperfusion times greater than 15 seconds were considered abnormal. This sequence was repeated postoperatively after the radial artery cannulae were removed. A total of 68 tests were performed before cannulation; 3 showed an abnormal Allen's test, a finding confirmed by pulse oximetry evaluation. The Allen's test was indeterminate 13 times. In all of these cases, pulse oximetry demonstrated collateral blood flow. When collateral circulation was determined to be present by Allen's test, it was also found to be present with pulse oximetry. Three days after cannulation was discontinued, 8 patients had abnormal Allen's test results, a finding again confirmed by pulse oximetry evaluation. Of 15 patients with indeterminate Allen's test results, 12 had collateral blood flow determined by pulse oximetry and 3 had abnormal results. The ability of pulse oximetry to detect collateral circulation was significantly different (P less than 0.001) when compared with Allen's test both before and after radial artery cannulation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1997

Predictability of extracranial/intracranial bypass function: a retrospective study of patients with occlusive cerebrovascular disease.

OBJECTIVE: When the efficacy of extracranial/intracranial bypass surgery is discussed, can we include the patients with extensive collateral circulation through the bypass and those with poor collateral circulation in the same group? The bypass function should be determined not by the patency of the bypass but by the extent of collateral circulation through the bypass. We retrospectively analyzed our patients to determine whether the extent of bypass flow can be predicted from the results of preoperative studies. METHODS: In 51 hemispheres of 44 consecutive patients who underwent extracranial/intracranial bypass surgery, correlation between the extent of bypass flow and the preoperative results of angiographic and stimulated cerebral blood flow studies were investigated. RESULTS: The bypass function is highly predictable with the aid of preoperative studies. In 11 hemispheres that showed both retrograde spontaneous circulation via leptomeningeal anastomoses and decreased reactivity to acetazolamide of cerebral blood flow in an area distal to the arterial lesion, collateral circulation through the bypass developed well and reactivity to acetazolamide improved. In all of 13 hemispheres that showed normal reactivity to acetazolamide, the bypass was patent but the collateral circulation did not develop well. In only 4 of 24 hemispheres with spontaneous antegrade circulation distal to the lesion was there satisfactory collateral circulation through the bypass. CONCLUSION: Our results indicate that improvement of the hemodynamic status by bypass surgery should be expected only in patients with both spontaneously developed leptomeningeal anastomoses and decreased reactivity to acetazolamide.

Acetazolamide↗
PubMed1994

[The effect of an extracranial occlusive lesion of the branches of the aortic arch on the status of the intracranial circulation].

Unilateral occlusion of extracranial cerebral arteries results in asymmetric intracranial flow rate against unaffected regional tissue circulation. Multiple occlusions entail reduction of intracranial circulation even in satisfactory collateral circulation. Reduction of tissue cerebral circulation occurs in well-defined occlusive processes with decompensated collateral circulation in the absence of carbogenic vascular responses. Co2 reactivity may serve a criterium of collateral circulation status and a positive prognostic sign in surgery planning.

Adolescent↗
PubMed2002

Relationship between pressure-derived collateral blood flow and diabetes mellitus in patients with stable angina pectoris: a study based on coronary pressure measurement.

UNLABELLED: Although the pressure gradient between the normal and stenotic vascular regions is known to be the most important factor for collateral vessel development, factors which are responsible for variations among patients with ischemic heart disease are not well known. Likewise, it is still not clear whether diabetes mellitus (DM) has any effect on coronary collateral development. Coronary angiography, the most commonly used technique for studying collateral circulation, may not be accurate in assessing collateral circulation because most collaterals are situated intramurally or are too small to visualize angiographically. Intracoronary pressure measurement is a new technique to provide accurate and quantitative information about the collateral circulation. Therefore, we sought the effects of DM on coronary collateral vessels in patients with coronary artery disease by using intracoronary pressure measurement technique. METHODS: Study material consisted of 40 patients (20 diabetic) with chronic ischemic heart disease referred to angiography laboratory due to their ischemic symptoms verified previously with at least one non-invasive test. All of the patients had single vessel disease with more than 70% narrowing and had undergone PTCA and/or stent implantation procedure for this vessel. Quantitative coronary angiographic analysis (QCA) and all of the coronary pressure measurements were performed both pre- and post-revascularization procedure. After angiography, a fiber-optic pressure monitoring guidewire (Pressure wire, RADI Medical Systems, Inc., Reading, Massachusetts) was advanced to the stenosis to be dilated. The same wire was used as a guidewire for the angioplasty catheter. During complete occlusion with balloon inflation, distal pressure was recorded as coronary wedge pressure (CWP). As a more valuable parameter, collateral flow index (CFI) was determined by the ratio of simultaneously measured CWP (mmHg) to mean aortic pressure (Pa, mmHg, obtained from the guiding catheter) (CFI: CWP/Pa). RESULTS: Pressure measurements were performed on 20 diabetic and 20 non-diabetic patients. The mean value of CWP was 18.1 8.6 mmHg in the diabetic group and 26.8 +/- 9.6 mmHg in the non-diabetic group; this difference was statistically significant (p < 0.01). Also, the mean value of CFI was significantly higher in the non-diabetic group (0.17 +/- 0.08 in the diabetic group and 0.25 0.09 in the non-diabetic group; p < 0.01). CONCLUSION: This study demonstrated that the coronary collateral vessel development is impaired in diabetic patients compared with non-diabetic patients.

Angina Pectoris↗
PubMedDate not supplied

A comparison of the results of A-C bypass grafting in collateral and non-collateral groups.

Ninety patients who had aorto-coronary bypass grafting were divided into two groups: a collateral group, which had coronary arterial stenosis or occlusion with collateral circulation, and a non-collateral group, which had coronary arterial stenosis or occlusion without collateral circulation. The number of coronary arteries visualized through collateral circulation in coronary angiograms (CAG) was 32, left anterior descending arteries (LAD) 17, right coronary arteries (RCA) 11, and left circumflex arteries (LCX) 4. The results of A-C bypass grafting in the collateral and non-collateral groups were compared. Surgical mortality was 0% in the collateral group, and 5.4% in the non-collateral group. The differences in graft patency and graft flow between the two groups were not statistically significant. However, left ventricular ejection fraction and myocardial perfusion, which was estimated by thallium-201 myocardial perfusion scintigram, were significantly improved after A-C bypass in the collateral group. Although the coronary arteries visualized through collateral vessels seemed too narrow to undergo graft anastomosis, they were, in fact, large enough. A-C bypass grafting was achieved with more satisfactory results in the collateral group than in the non-collateral group.

Angina Pectoris↗
PubMed1999

The simple indicator for revascularization of acute middle cerebral artery occlusion using angiogram and ultra-early embolectomy.

BACKGROUND: The purpose of the study was: (1) to find a clinical indicator for revascularization of acute middle cerebral artery (MCA) occlusion using angiograms of 100 patients examined immediately after onset and treated medically and (2) to investigate 10 ultra-early MCA embolectomies. METHODS: Quantity of collateral circulation, based on time required for conduction of contrast media to the insular portion of the MCA from the anterior cerebral artery, MCA conduction time (MCT) was graded as: Grade 1: In the arterial phase, there was conduction not only to the insular portion of the MCA but also to proximal M2; Grade 2: Conduction to the insular portion was present in late arterial phase; Grade 3: Conduction was present in capillary phase; Grade 4: Conduction was present in venous phase; Grade 5: No conduction was seen. The results of embolectomy are discussed. RESULTS: MCT can predict the extent of resultant low-density area on computed tomographic scan. For Grades 3, 4, or 5, embolectomy could be considered superior to medical treatment, if the low-density area was localized in the basal ganglia or centrum semiovale after surgery. Consequently, embolectomy was effective in four cases recanalized within 6 hours of onset. Except for one Grade 5 case, the remaining nine cases showed neither lethal hemorrhagic infarction nor brain edema. Overall outcome was significantly better than cases treated medically (p < 0.05), but some cases did not recover from hemiparesis due to infarcts in the area of the lenticulostriate arteries. CONCLUSIONS: MCT helps to predict the applicability of revascularization of acute MCA occlusion. Efficacy of embolectomy depends on revascularization within 6 hours of onset. Even after complete MCA flow restoration, infarcts in the area of the lenticulostriate arteries cannot always be prevented.

Acute Disease↗
PubMed2000

The significance of the cerebral collateral capacity in patients with carotid atheroma.

OBJECTIVES: to identify the echodensity, stenosis of carotid plaques and cerebral collateral capacity that were associated with various ipsilateral presentations (retinal, cerebrovascular, asymptomatic). DESIGN: cross-sectional study. MATERIALS: forty-four patients, with 44 plaques associated with various presentations, were studied. METHODS: the duplex images of the plaques were analysed echomorphologically in a computer by means of Grey Scale Median (GSM) [hypoechoic (low GSM), hyperechoic (high GSM)]. The percentage (%) reduction of the mean velocity in the middle cerebral artery (PRMCA) on transcranial Doppler, during clamping in carotid endarterectomy, was evaluated to distinguish the competent cerebral collateral supply (low PRMCA) from the non-competent one (high PRMCA). RESULTS: the retinal symptoms were associated with plaques of low median GSM (0), severe median stenosis (90%) and low median PRMCA (0.31) as contrasted with the cerebrovascular symptoms (17, 84%, 0.47, respectively) and asymptomatic status (32, 83%, 0.4, respectively) [(p =0.038 (GSM), p =0.67 (stenosis), p=0.15 (PRMCA)]. The retinal and the cerebrovascular symptoms were distinct in terms of PRMCA (p=0.045). CONCLUSIONS: the retinal symptoms were produced by hypoechoic and possibly embologenic plaques, whereas the cerebrovascular ones possibly by the combination of carotid embolism and a non-competent cerebral collateral circulation. Asymptomatic status was associated with the absence of any relevant mechanism.

Adult↗
PubMed1998

Neuroprotective agents in acute ischemic stroke.

Recent scientific data suggest that there is a "window of opportunity" between the onset of brain ischemia and irreversible neuronal death. Although neurons can withstand complete absence of blood flow for only minutes, collateral circulation typically surrounds the "core" of the stroke. In these brain regions known as the ischemic penumbra, brain tissue can survive for several hours following stroke onset. Recent studies suggest that neuroprotective agents would give these viable neurons the chance for recovery. This article reviews the mechanisms of ischemic neuronal injury, mechanism of action of neuroprotective agents, current neuroprotective clinical trials, and guidelines for patient care management.

Acute Disease↗
PubMed1991

The clinical importance of the inferolateral trunk of the internal carotid artery.

The inferolateral trunk (ILT) of the internal carotid artery (ICA) is a branch that arises inferiorly from the C4 segment of the cavernous ICA. It provides blood supply to the 3rd, 4th, and 6th cranial nerves, as well as to the gasserian ganglion. The ILT anastomoses to branches of the internal maxillary artery, providing collateral circulation between the external carotid artery and the ICA systems. Retinal and cerebral emboli can arise from the external carotid artery system and travel via the ILT to the ICA. Cranial nerve palsies may result after occlusion of the ILT. We present the cases of four patients who had iatrogenic neurological dysfunction subsequent to intravascular procedures that involved the ILT. These cases provide further clinical confirmation of the importance of this blood vessel. A 5th case involving iatrogenic occlusion of the ILT and no neurological deficit is also presented, demonstrating that the ILT is not the sole blood supply of the cranial nerves in the cavernous sinus.

Adult↗
PubMed1986

The absence of the internal carotid artery: report of two cases.

The absence of the internal carotid artery (ICA) is a very rare anomaly. Since the first description of the condition in 1787, only 60 cases have been reported in the literature. We report two cases of absence of the left ICA amongst 2195 carotid angiograms performed in the Department of Neuroradiology at the Royal Brisbane Hospital over a period of 4 years. The first patient was suffering from obstructive hydrocephalus; the second from right cerebellopontine angle syndrome. Cerebral angiography by catheterization of the aorta revealed the absence of the left ICA. The collateral circulation to the left cerebral hemisphere was provided by the vertebrobasilar system via a dilated left posterior communicating artery. In the first patient, the absence of the ICA was coincidental with other congenital anomalies of the cervico-occipital junction. In the second patient, the dilated vertebrobasilar system was responsible for compressing the right cranial nerves VII and VIII. It is emphasized that in some cases of cerebellopontine angle syndromes, thorough investigation of the cerebral vessels is necessary.

Adult↗
PubMed1995

Transcranial color-coded real-time sonography of intracranial veins. Normal values of blood flow velocities and findings in superior sagittal sinus thrombosis.

Sonographic findings in patients with superior sagittal sinus thrombosis were compared to those in healthy adults. Two patients with angiographically verified superior sagittal sinus thrombosis were examined by transcranial color-coded real-time sonography (TCCS) after intravenous application of a pulmonary stable ultrasound contrast agent. For comparison, 10 patients without venous pathology had contrast-enhanced TCCS; in addition, 30 healthy adults had plain TCCS to determine the identification rate for deep and superficial venous segments and to define normal values of venous blood flow velocities. The straight sinus was identified in 22 of 30 healthy subjects by plain TCCS, and in 9 of 10 patients by contrast-enhanced TCCS. The mean peak and angle-corrected blood flow velocity was 19.1 +/- 7.1 cm/sec. The superior and inferior sagittal sinuses were identified by contrast-enhanced TCCS in 2 and 1 subjects, respectively; they were never seen on plain TCCS. In the 2 patients with sagittal sinus thrombosis a distinct increase of blood flow velocity was recorded from the straight sinus (83 and 92 cm/sec), most likely reflecting collateral circulation. These preliminary data indicate that TCCS and particularly contrast-enhanced TCCS permit identification and blood flow measurements within the deep and occasionally, the superficial venous system. TCCS may contribute to an assessment of hemodynamic repercussions of venous thrombosis and may indicate the risk of venous infarction and hemorrhage.

Adult↗
PubMed2004

Carotid perfusion CT with balloon occlusion and acetazolamide challenge test: feasibility.

Carotid balloon test occlusion (BTO) is used to assess the collateral circulation and cerebrovascular reserve in patients in whom carotid artery occlusion is contemplated. Eight patients in whom the test was successful were evaluated with perfusion computed tomography (CT) in the resting state and after acetazolamide challenge. Three of the patients showed symmetric blood flow and normal response to acetazolamide. One of them underwent permanent carotid occlusion and did not develop any delayed ischemic stroke. The remaining five patients showed asymmetric blood flow. One of them had markedly low blood flow and abnormal response to acetazolamide. The patient developed ipsilateral hemispheric stroke following permanent carotid occlusion after the superficial temporal artery to middle cerebral artery bypass graft occluded. In the other four patients, the steal phenomenon was seen in ipsilateral and contralateral hemispheres. Although definitive quantitative values for perfusion CT are not yet standardized, it may be feasible to predict that the patients with symmetric blood flow and normal acetazolamide-enhanced challenge test results will do well after permanent carotid occlusion. Patients with asymmetric blood flow and abnormal response to the acetazolamide challenge test may require a revascularization procedure to protect them from delayed ischemic stroke.

Acetazolamide↗
PubMed1982

Transaortic occlusion of collateral arteries to the lung by detachable valved balloons in a patient with tetralogy of Fallot.

A 5-year-old boy with tetralogy of Fallot, near-atresia of the right ventricular outflow tract and large collateral arteries to the lungs underwent an infundibulectomy without closure of the ventricular septal defect. Further surgery required preliminary reduction of the collateral circulation. The collateral arteries were successfully occluded by metrizimide-filled balloons. There was no change in arterial oxygen saturation, nor were there any complications. This new technique has significant advantages over existing alternatives.

Aortography↗