Dynamics of the Collateral Circulation in Patients with Subclavian Steal

Abstract

The occurrence of retrograde blood flow in the ipsilateral vertebral artery of patients with proximal occlusion of the subclavian or innominate artery has been amply demonstrated by selective angiography. However, since flow artifacts may be induced by the physical or chemical effects of injections of contrast media, it was thought desirable to employ a different method for physiologic demonstration of the reversed flow. In the first case, cardio-green dye was injected into the innominate artery and a dilution curve was recorded from the left brachial artery. The early appearance of the dye (6 seconds) proved that a short circuit existed between the arterial injection and sampling sites, and confirmed the authenticity of the reversed vertebral flow shown in previous angiograms. In the second patient, who had symptoms of cerebral ischemia during exercise of the left (affected) arm, dye injected into the left carotid artery did not appear early in the brachial artery of the resting left arm. When it was injected during a period of intense hyperemia of the left arm, a fraction of the dye did appear early. This confirmed that, when the demand of the arm increased, blood was shunted to it not only from the vertebral-basilar system but also from the carotid system. The importance of anatomic factors was evident in another case in which absence of the anticipated retrograde flow was explained by the fact that the vertebral artery arose directly rectly from the aorta and did not communicate with the affected subclavian artery. These observations illustrate how radiographic and hemodynamic technics may usefully be combined to assess the effects of acquired diseases of the major blood vessels.

Prenatal ultrasound findings, genetic testing, and literature review of Isolated left subclavian artery

“…If ILSA patients have no clinical symptoms, they do not choose surgery but follow up 19,20 ; patients who need intracardiac repair will undergo ILSA surgery as appropriate. The surgical division and reimplantation of ILSA to aortic arch or the left common carotid artery remains the primary choice 21,22 .…”

“…If ILSA patients have no clinical symptoms, they do not choose surgery but follow up 19,20 ; patients who need intracardiac repair will…”

Retrograde Flow in the Vertebral Artery

“…2,8,9,11 Under certain circumstances, all branches of the proximal subclavian artery, certain branches of the external carotid artery, and even the internal carotid artery may supply blood to the ischemic arm. The vertebral artery, however, because of its size and direct connection to the contralateral vertebral at its junction with the basilar artery, is the most important of these.…”

Extrakraniale Gefäßveränderungen als Ursache zerebrovaskulärer Insuffizienz

“…Nach den bisherigen angiographischen Untersuchungsergebnissen ist anzunehmen, daß meistens Stenosen oder Verschlüsse der extrazerebralen Arterien die Ursache der zerebralen Insuffizienzerscheinungen sind. Die Fortschritte der rekonstruktiven Gefäßchirurgie sollten den Kliniker zu einer anderen Einstellung gegenüber einem chirurgischen Eingriff bei diesen klinischen Befunden und zu einer erweiterten Indikation auch bei multiplen 13,16,20,21,22,27,34,35,37,39,41,45,55,58,59,64,67,68,74,77,78,82,83,86,88,95,102,104,110,114) Gefäßveränderungen veranlassen. Die guten Resultate der Gefäßchirurgie in diesen Arterienabschnitten (1,14,23,26,29,30,31,32,39,43,48,49,52,54,85,92,98,107,115)…”