Fate of coronary collateral circulation after aorto-coronary saphenous vein bypass grafts.
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The pre- and postoperative patterns of coronary artery collateral circulation have been studied in 34 patients who had saphenous vein bypass grafting. When the graft remained patent homocoronary collaterals could not be visualized after operation, but new intercoronary anastomoses frequently developed to other diseased arteries. When the graft and the bypassed artery were both obstructed there was a high incidence (5 out of 11) of myocardial infarction despite good preoperative collaterals. (+info)
Effect of aorto-coronary grafts and native vessel patency on the occurrence of angina pectoris after coronary bypass surgery.
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Exercise testing of 52 patients on average 11 months after coronary bypass surgery for the relief of angina pectoris disclosed improvement in total work (P is less than 0.001), maximal tolerated load (P is smaller than 0.001), maximal heart rate (P is smaller than 0.01), and reduction of maximal ST segment depression (P is smaller than 0.001) in a group of 36 patients with all grafts patent. In another group of 16 patients with one or more grafts occluded the only significant change was a reduction in the maximal ST segment depression (P is smaller than 0.01). Early and late postoperative angiograms showed that 75 per cent of the grafts that became occluded were already closed a few weeks after operation. Occluded grafts were accompanied by persistence of collaterals, which disappeared or dimished in the majority of patients with patent grafts. Progression in native vessel lesions occurred in 40 per cent of patients. It was related to the grafting procedure (P is smaller than 0.01) but not to the state of grafts. The change in native vessels and other variables studied was equal in the patent and occluded graft groups, justifying the conclusion that graft patency was the major factor alleviating angina after operation. (+info)
The contribution of the external carotid artery to cerebral perfusion in carotid disease.
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PURPOSE: In the presence of carotid occlusion, the external carotid artery (ECA) becomes an important source of cerebral blood flow, especially if the circle of Willis is incomplete. The contribution of the ECA to hemispheric blood flow in patients with severe ipsilateral carotid stenosis has never been previously investigated. METHODS: One hundred eight patients were monitored during sequential cross-clamping of the external (ECA) and then ipsilateral internal carotid artery (ICA) during carotid endarterectomy using transcranial Doppler sonography (TCD) (Neuroguard CDS, Los Angeles, Calif), to measure middle cerebral artery blood flow velocity, and near-infrared spectroscopy, to measure regional cerebral oxygen saturation (CsO(2)) (Invos 3100A; Somanetics, Troy, Mich). RESULTS: On the ipsilateral ECA cross-clamp, the median fall in CsO(2) was 3% (interquartile range, 1%-4%; P <.0001). On addition of the ICA cross-clamp there was a further fall of 3% and a total fall of 6% (3%-9%; P <.0001). The median percentage fall in middle cerebral artery blood flow velocity on ECA clamping was 12% (4%-24%; P <.0001); on ICA clamping it was 48% (25%-74%; P <.0001). Falls in TCD on ECA clamping were greater with increasing severity of ipsilateral ICA stenosis. The correlation between CsO(2) and TCD on external clamping, although less strong than that on internal clamping, was statistically significant r = 0.32; P =.01; Spearman rank correlation). CONCLUSIONS: The falls in TCD and CsO(2) were of a similar order of magnitude and must therefore reflect a fall in cerebral perfusion. The ipsilateral ECA contributes significantly to intracranial blood flow and oxygen saturation in severe carotid stenosis. (+info)
The blood supply of the lateral epiphyseal arteries in Perthes' disease.
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We performed superselective angiography in 28 hips in 25 patients with Perthes' disease in order to study the blood supply of the lateral epiphyseal arteries (LEAs). Interruption of the LEAs at their origin was observed in 19 hips (68%). Revascularisation in the form of numerous small arteries was seen in ten out of 11 hips in the initial stage of Perthes' disease, in seven of eight in the fragmentation stage and in five of nine in the healing stage. Penetration of mature arteries into the depths of the epiphysis was seen in four of nine hips in the healing stage. Vascular penetration was absent in the weight-bearing portion of the femoral head below the acetabular roof. Interruption of the posterior column artery was seen where it passed through the capsule in seven hips when they lay either in internal rotation or in abduction with internal rotation. We suggest that in Perthes' disease the blood supply of the LEAs is impaired at their origin and that revascularisation occurs from this site by ingrowth of small vessels into the femoral epiphysis. This process may be the result of recurrent ischaemic episodes. (+info)
Acute coronary insufficiency. An urgent surgical condition.
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In 41 of 220 consecutive patients who had a coronary artery bypass operation between July 1973 and March 1974 the operation was for acute coronary insufficiency (recurrent chest pain with transient electrocardiographic changes persisting after admission to hospital). Their mean age was 54 (range 33-70 years). Eleven patients had had angina before, 14 had had at least one myocardial infarction, and 16 presented de novo. Eight of the latter 16 patients required only a single graft, usually to the left anterior descending artery, a significantly greater number than the two of the other 25 patients (P less than 0.01). Fourteen of these 16 patients had normal ventricular contraction, a significantly higher proportion than the 13 of the remaining 25 (p less than 0.05). No collaterals were seen in any of the 10 with single-vessel disease, which was significantly fewer than five out of 18 with double- and nine out of 13 with triple-vessel disease (P less than 0.005). Patients with rapidly developing obstruction, especially in the proximal left anterior descending artery, may not have time to develop collaterals, present acutely with good ventricular function, and may be particularly at risk. There was no operative mortality. The patients had a perioperative myocardial infarction, and there was one late death. At follow-up averaging 9-7 months (range 5-14 months) 32 (80%) patients were angina-free, no myocardial infarctions had occurred, and 85% were fully employed. Urgent coronary artery bypass grafting is a safe and effective treatment for acute coronary insufficiency. (+info)
Collateral configuration of the circle of Willis: transcranial color-coded duplex ultrasonography and comparison with postmortem anatomy.
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BACKGROUND AND PURPOSE: The anterior communicating artery (AcoA) and posterior communicating arteries (PcoA) of the circle of Willis provide the main route for collateral blood flow in cases of carotid artery obstruction. Transcranial color-coded duplex ultrasonography (TCCD) allows real-time measurement of the collateral function of the AcoA and PcoA. The primary objective of this study was to determine the collateral artery threshold diameters for supplying collateral flow. METHODS: In 12 acute stroke patients with a median age of 75 years (51 to 91 years), the collateral integrity of the circle of Willis as assessed by TCCD and carotid compression tests was compared with their postmortem anatomy. The lengths and diameters of the collateral arteries were measured. RESULTS: TCCD demonstrated absent anterior collateral flow in 3 patients. In 1 of these patients, absence of anterior cross-flow was due to an occluded anterior cerebral artery, which was revealed at autopsy. Absent posterior collateral flow was found in 14 hemispheres. In 2 of these hemispheres, autopsy revealed a fetal configuration of the posterior cerebral artery hampering posterior collateral flow. The median (range) diameters as found at autopsy of the functional (n=19) and nonfunctional (n=16) collateral arteries of the circle of Willis were 1.1 (0.4 to 2.0) and 0.5 (0.3 to 0.7) mm, respectively (P=0.003). PcoA diameters were found to correlate negatively (rho=-0. 50, P=0.01) to the diameters of their accessory P1 segments. CONCLUSIONS: The threshold diameter allowing for cross-flow through the primary collateral arteries of the circle of Willis is between 0. 4 and 0.6 mm. (+info)
Ambulatory venous pressure revisited.
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PURPOSE: The purpose of this study was to describe a method for measuring the deep venous pressure changes in the lower extremity and compare it with those obtained in the dorsal foot vein. METHODS: After cannulation of the posterior tibial vein, a catheter with a pressure transducer in its tip was inserted and placed at the knee joint level. The dorsal foot vein was also cannulated. Pressures were recorded simultaneously at both sites during toe stands and repeated with the probe in the upper, middle, and lower calf. RESULTS: The study was performed in 45 patients with signs and symptoms of chronic venous insufficiency. Duplex Doppler scanning and ascending and descending venography performed before pressure measurements revealed saphenous vein incompetence in 11 lower extremities, incompetent perforators in 11 extremities (eight were combined with saphenous incompetence), and marked compression of popliteal vein with plantar flexion in 28 extremities. No significant deep axial reflux was observed on duplex Doppler examination or descending venography. No morphologic outflow obstruction was detected. The mean deep pressure at the knee joint level fell during toe stands, -15% +/- 27 (SD), and the mean dorsal foot vein pressure drop was even more marked, -75% +/- 22 (SD). Although the exercise pressure in the dorsal foot vein decreased in all patients (range, 13-90% drop), the popliteal vein pressure increased (4-72%) in nine limbs, decreased only marginally if at all in 15 limbs (0-15%), and fell more markedly in 21 extremities (22-65%). Deep vein recovery time was considerably shorter overall as compared with the findings by the dorsal vein measurement. In the comparison of limbs with and without superficial reflux, the recovery times in the deep system were significantly shorter in limbs with superficial incompetence. CONCLUSION: Ambulatory dorsal foot venous pressure is not always accurate in detecting changes in the pressure of the tibial and popliteal veins. Although dorsal foot venous pressure may be normal, deep venous pressure may decrease to a lesser degree or even increase. (+info)
Visceral aneurysms in Ehlers-Danlos syndrome: case report and review of the literature.
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A patient with Ehlers-Danlos syndrome type IV had a celiac artery aneurysm. There are only nine previously published cases of visceral artery aneurysms in this condition, and surgical management was used in only four of them. This is, we believe, the first published report of a successfully treated celiac artery aneurysm in this condition in which the hazards of treatment and our rationale are explained. The literature of this rare problem is also reviewed. (+info)