A 64-year-old man presented with left-sided weakness with an initial NIH Stroke Scale score of 11. Brain CT imaging showed a hyperdense artery sign of right middle cerebral artery (MCA) occlusion (figure 1, A and B). Brain MRI showed the susceptibility vessel sign (SVS) on gradient recalled echo and hyperintense vessels (HV) on fluid-attenuated inversion recovery images (figure 1, C and D). Ang...

BACKGROUND The development of collateral circulation plays an important role in protecting tissues from ischemic damage, and its stimulation has emerged as one of principal approaches to therapeutic angiogenesis. Clinical observations have documented substantial differences in the extent of collateralization among patients with coronary artery disease (CAD), with some individuals demonstrating ...

Catecholamine stimulation of alpha1-adrenoceptors exerts growth factor-like activity, mediated by generation of reactive oxygen species, on arterial smooth muscle cells and adventitial fibroblasts and contributes to hypertrophy and hyperplasia in models of vascular injury and disease. Adrenergic trophic activity also contributes to flow-mediated positive arterial remodeling by augmenting prolif...

We compared development of feline hindlimb collateral circulation after acute occlusion of the terminal aorta by ligation, thrombus formation, and formation of a "closed" aortic loop containing thromboplastin. Collateral circulation development was assessed by aortograms, scintillation scans, neurological signs following occlusion, measurement of hindlimb muscle blood flow, and forelimb and hin...

We describe a case of chronic total occlusion of the right coronary artery ostium 5 months after a repeated Bentall procedure in a patient with Behçet's disease. In this patient, an antegrade approach to delivering the guidewire during percutaneous coronary intervention was not successful. Coronary angiography revealed the existence of collateral blood supply from the left coronary artery. Usin...

BACKGROUND AND PURPOSE In proximal anterior circulation occlusive strokes, collateral flow is essential for good outcome. Collateralized vessel intensity in TOF- and contrast-enhanced MRA is variable due to different acquisition methods. Our purpose was to quantify collateral supply by using flow-weighted signal in TOF-MRA and blood volume-weighted signal in contrast-enhanced MRA to determine e...

Congenital absence of an internal carotid artery is a rare anomaly. Less than 1 00 cases have been reported in the English literature. It is usually associated with collateral flow to the involved vascular territory, so neurologic deficits are few. However, this anomaly is also associated with a high occurrence of intracranial aneurysms. We report two cases of absent internal carotid artery wit...

Three patients with angina pectoris are reported in whom occlusion of the left main coronary artery was found at coronary arteriography. In these three patients left ventricular function was well preserved. In all three the right coronary artery was dominant and there were prominent epicardial and septal collateral vessels to the territories normally supplied by the left anterior descending and...

The effect of sympathectomy on the size of the collateral vessels in acute arterial ligation in a hind limb was measured by an angiographic angiometric technic and by noting the pressure in the ligated artery distal to the ligature. The size of the largest collateral vessel present on the sympa-thectomized side was the same as that on the innervated side. The blood pressure in the ligated arter...

Portal hypertension (PHT) is associated with hemodynamic changes in intrahepatic, systemic, and portosystemic collateral circulation. Increased intrahepatic resistance and hyperdynamic circulatory alterations with expansion of collateral circulation play a central role in the pathogenesis of PHT. PHT is also characterized by changes in vascular structure, termed vascular remodeling, which is an...