Variant of subclavian steal syndrome: unusual anatomical relationship between left subclavian artery and left vertebral artery.

A woman in her 70s presented to her general practitioner (GP) with a 3-month history of left upper arm pain and weakness. A significant difference in bilateral blood pressures was noted and a further history elicited coolness in her left arm without functional compromise. A CT angiography revealed variant subclavian steal syndrome with a subclavian arterial stenosis, which was proximal to both the internal mammary and thyrocervical trunk and her left vertebral artery originating from the aortic arch. She was referred to a vascular surgeon but declined surgical intervention. Her symptoms remain stable with 6-month follow-up from her GP. This case highlights the importance of considering vascular aetiologies in upper limb pain and weakness. Our case reviews the differential diagnoses of upper limb pain and weakness, consequently leading to the discussion of an interesting variant of subclavian stenosis.

Subclavian Artery-Carotid Artery Bypass for Subclavian Artery or Common Carotid Artery Severe Stenosis or Occlusion.

Various surgical treatments are available for occlusive subclavian and common carotid artery diseases. Nevertheless, to date, when cerebral endovascular treatment is utilized, revascularization via direct surgery may be required. This study reported five symptomatic cases of revascularization for CCA and SCA occlusive and stenotic lesions that were expected to be challenging to treat with endovascular treatment. We performed subclavian artery-common carotid artery or internal carotid artery bypass using artificial blood vessels or saphenous vein grafts in five patients with subclavian steal syndrome, symptomatic common carotid artery occlusion, and severe proximal common carotid artery stenosis. In this study, good bypass patency was achieved in all five cases. Although there were no intraoperative complications, one patient had a postoperative lymphatic leak. Moreover, there was no recurrence of stroke during postoperative follow-up for an average of 2 years. Conclusively, subclavian artery-common carotid artery bypass can be an effective surgical treatment for common carotid artery occlusion, proximal common carotid artery stenosis, and subclavian artery occlusion.

Coronary Subclavian Steal Syndrome in a 73-Year-Old Woman Presenting with Angiographically Confirmed Subclavian Artery Stenosis Proximal to the Left Internal Mammary.

BACKGROUND Coronary subclavian steal syndrome (CSSS) is an uncommon condition in which a high-grade stenosis of the subclavian artery proximal to an internal mammary artery bypass graft results in retrograde blood flow of the bypass graft. This report is of CSSS in a 73-year-old woman who presented with ventricular tachycardia and angiographically confirmed subclavian artery stenosis proximal to the left internal mammary artery (LIMA) bypass graft 3 years following coronary artery bypass grafting (CABG). CASE REPORT The patient was a 73-year-old woman with a past medical history of multivessel coronary artery disease, found on preoperative evaluation. She underwent 2 vessel CABG in 2018. She was found to have ischemic cardiomyopathy, ejection fraction of 30% to 35% despite revascularization, and an implantable cardiac defibrillator (ICD). Three years following uncomplicated CABG, the patient presented with angina and sustained ventricular tachycardia; ICD therapy was unsuccessful. Ischemia was the etiology of the sustained ventricular tachycardia, and the patient underwent cardiac catheterization, demonstrating high-grade subclavian artery stenosis proximal to the LIMA bypass graft. Intervention of the 80% lesion of the native left anterior descending artery was done with placement of a 2.75×16-mm drug-eluting stent. The patient responded well to treatment, with no subsequent ventricular tachycardia on outpatient follow-up. CONCLUSIONS This report has shown that in patients who present with symptoms of acute coronary syndrome and a history of CABG involving the LIMA, the possibility of CSSS should be considered and investigated by coronary artery imaging so that diagnosis and management are not delayed.

Critical analysis of vertebral artery flow patterns/subclavian steal detected by cerebrovascular duplex ultrasound examinations and its clinical implications.

BACKGROUND: The prevalence of subclavian steal (defined as retrograde/bidirectional vertebral artery flow) in the general population and in patients undergoing cerebrovascular duplex ultrasound (CDUS) examinations is variable. This is the largest study to date to analyze the incidence of duplex-suggested subclavian steal in 5615 CDUS examinations over a 1-year period and to examine its clinical implications. PATIENT POPULATION AND METHODS: All consecutive CDUS examinations performed over a 1-year period were analyzed for the presence of subclavian steal. Indications of testing, presence of posterior cerebral circulation/subclavian steal symptoms, and any interventions for subclavian steal were analyzed. RESULTS: A total of 171 of 5615 (3.1%) CDUS examinations were found to have subclavian steal (duplex-suggested). One hundred seventeen (2.1%) had retrograde flow and 54 (1%) had bidirectional flow. Of 171, 104 (60.8%) were left sided. Indications for CDUS were post-carotid endarterectomy/carotid artery stenting surveillance in 39 patients (22.8%), surveillance for progression of carotid stenosis in 76 patients (44.4%), transient ischemic attack/stroke in 26 patients (15%), asymptomatic screening/carotid bruit in 18 patients (10.5%), and isolated posterior cerebral circulation symptoms in 12 patients (7%). A total of 63% patients had associated >50% carotid stenosis. The mean arm Doppler pressure gradient was 32.2 mm Hg for asymptomatic patients vs 37 mm Hg for patients with posterior circulation symptoms (P = .3254). There were significant differences between the mean systolic arm pressure for patients with retrograde vs antegrade vs bidirectional flow (105 mm Hg vs 146 mm Hg vs 134 mm Hg, respectively, P < .0001). All patients with retrograde flow had >50% subclavian stenosis or occlusion (100 of 117 had subtotal/total occlusion) except for one patient. Meanwhile, 52 of 54 patients with bidirectional flow had >50% subclavian stenosis (6 of 54 with subtotal/total occlusion), whereas two patients were normal/<50% stenosis (P < .0001). Overall, 26 of 171 patients (15.2%) had interventions for disabling symptoms. Eleven of 26 of all interventions were for disabling arm claudication, and only 10 of 171 patients (5.8%) were intervened for disabling posterior circulation symptoms with complete resolution of symptoms in all except one. At a late follow-up with a mean of 18 months (range: 1-37 months), there was no late major stroke with only two lacunar infarcts (not subclavian steal related). There were also seven late deaths, none stroke related. CONCLUSIONS: The incidence of subclavian steal in patients who undergo CDUS is relatively rare. Most of these patients are asymptomatic and can be treated conservatively, and only a few may need intervention for disabling symptoms with good symptom resolution.

Headache may be the only symptom of subclavian steal syndrome after thoracic endovascular aortic repair.

Thoracic endovascular aortic repair (TEVAR) is currently the treatment of choice for thoracic aortic disease. In select cases, the TEVAR stent must occlude the left subclavian artery. This is usually well tolerated, but the subclavian steal syndrome (SCSS) may occur. Vertebrobasilar insufficiency can cause headaches, but reports of headache as the only symptom of SCSS are very rare. Thus, this may be under-recognised. To increase the awareness of this complication we describe the course of a patient who developed chronic intermittent headaches after intentional occlusion of the left subclavian artery with a TEVAR stent. Revascularisation may be required to prevent adverse neurological outcomes from SCSS. Some authors recommend prophylactic revascularisation whenever the left subclavian artery is sacrificed during TEVAR. However, transposition or bypass of this artery is not without risk and mild symptoms, such as secondary headache, can be fully controlled with conservative measures that reduce steal pathophysiology.

Carotid Subclavian Bypass for the Treatment of Coronary Subclavian Steal Syndrome.

Coronary subclavian steal syndrome is an uncommon cause of angina in patients with a previous coronary artery bypass graft procedure. The patient had chest pain with the exertion of the left upper limb, difference in blood pressure between the left and right arm, occlusion at the ostium of the left subclavian artery. He underwent carotid subclavian bypass surgery that was successful in relieving symptoms. On the other hand, the patient had an embolic stroke related to the procedure and further assessment may be necessary.

The use of 4-dimensional magnetic resonance angiography as a noninvasive procedure to diagnose subclavian steal syndrome in a dog.

CASE DESCRIPTION: A 5-year-old 4.1-kg (9.0-lb) spayed female Toy Poodle was referred because of a 6-month history of sporadic signs of neck pain. CLINICAL FINDINGS: Diagnostic imaging with MRI and CT revealed a dilated radicular artery connecting the right and left vertebral arteries and causing mild compression of the spinal cord. The left subclavian artery caudal to the origin of the left vertebral artery was absent. Subclavian steal syndrome (SSS) was suspected. TREATMENT AND OUTCOME: The owner declined surgical treatment; thus, the dog was treated conservatively with glucocorticoids and analgesics. Eight months later, the dog's clinical signs were unchanged but palliated with the administration of glucocorticoids and analgesics, and 4-dimensional (4-D) magnetic resonance angiography (MRA) revealed that the left vertebral artery received blood supply from the right vertebral artery through the dilated radicular artery and that the left vertebral artery caudal to this site had retrograde flow and drained into the left subclavian artery, confirming the diagnosis of SSS. The owner again declined surgery, and conservative treatment continued. The dog's condition was unchanged at the last follow-up communication 11 months after 4-D MRA. CLINICAL RELEVANCE: Subclavian steal syndrome is an extremely rare condition in dogs, and our findings suggested that 4-D MRA could be used to definitively diagnose SSS in dogs.

Endovascular management of subclavian-steal syndrome in a patient with post-traumatic dissection of an aberrant right subclavian artery.

BACKGROUND: An aberrant right subclavian artery is the most common congenital anomaly of the aortic arch and may cause symptoms due to aneurysmal dilatation, stenosis or occlusion. We present a case of subclavian-steal syndrome due to post-traumatic dissection of an aberrant right subclavian artery. METHODS AND RESULTS: A 50 year-old man presented with dizziness and fainting episodes after exercising his right arm and a systolic blood pressure gradient of 40 mm Hg between the 2 arms. Suspecting a subclavian steal syndrome, a computed tomography angiography was requested which revealed an aberrant right subclavian artery with a severe stenosis proximal to the ostium of the vertebral artery. Transfemoral digital subtraction angiography showed a local dissection of the aberrant right subclavian artery with late retrograde filling of the ipsilateral vertebral artery. The lesion was successfully treated with primary stent implantation (9 mm x 40 mm, LIFESTAR, BARD). On interrogation, the patient recalled an injury to the right arm after falling off a ladder 10 years earlier, as a possible post-traumatic cause for the dissection. He had an uneventful outcome and is symptom-free 12 months down the line. CONCLUSIONS: The combination of post-traumatic dissection of an aberrant right subclavian artery resulting to subclavian steal syndrome is an extremely rare scenario. Endovascular management is a safe, minimally invasive alternative to open surgery.

Endovascular Treatment in the Subclavian Steal Syndrome: Series of 29 Patients

Subclavian steal syndrome is a group of symptoms resulting fromretrograde flow in the vertebral artery, "stealing" blood from the posterior intracranial circulation and other territories, caused by stenosis or occlusion of the subclavian artery proximal to the origin of the same vertebral artery, or even of the brachiocephalic trunk. Most of the time, it is an incidental finding in patients with other conditions or cerebrovascular risk factors. We report a series of 29 patients with an angiographic diagnosis, in which 7 received treatment (all endovascular), all with symptoms directly related to this condition. Advanced age, systemic arterial hypertension, diabetes mellitus, smoking and stroke were comorbidities frequently related. Six patients improved completely after the procedure and one remained with vertigo.

Coronary subclavian steal syndrome causing myocardial Infarction.

Coronary subclavian steal syndrome (CSSS) is a rare complication of the internal mammary artery (IMA) grafting in coronary artery bypass surgery. The technical definition is myocardial ischemia due to the reduced flow of blood, or flow reversal in the IMA graft. This in most cases results from hemodynamically significant proximal subclavian artery stenosis. The clinical presentation is variable and ranges from unstable angina to myocardial infarction, and in some cases, sudden cardiac arrest. CSSS is an entity that is hard to diagnose if one is not actively looking for it. The clinical diagnosis is often complicated, and the prevalence of the disorder is frequently underestimated. In this case presentation, we report a case of myocardial infarction that resulted from significant proximal subclavian artery stenosis.

Don't Ignore That Chest Pain: Positionally Dependent Coronary Subclavian Steal Syndrome.

Coronary subclavian steal syndrome (CSSS) is a complication incurred after coronary artery bypass grafting (CABG), characterized by retrograde blood flow through the left internal mammary artery (LIMA) graft to the left subclavian artery (SCA) distal to a SCA stenosis, thereby compromising myocardial perfusion from the LIMA despite its patency. We present a 40-year-old female with a history of triple-vessel CABG who presented with crescendo angina, notably when elevating her arms above her head. Atypical angina related to arm activity following successful LIMA bypass should prompt angiography directed to the left SCA, as well as to the LIMA graft. Typically, cases of CSSS are claudication dependent and not positionally related. This suggests a two-pronged pathophysiological mechanism of both demand ischemia and mechanical obstruction, which is not well described in previous literature.

Long-term Outcome of Axillo-axillary Bypass in Patients with Subclavian or Innominate Artery Stenosis.

BACKGROUND: Subclavian or innominate artery stenosis (SAS) may cause upper extremity and cerebral ischemia. In patients with symptomatic subclavian or innominate artery stenosis, percutaneous transluminal angioplasty is the treatment of first choice. When percutaneous transluminal angioplasty is technically restricted or unsuccessful, an extrathoracic bypass grafting, such as an axillo-axillary bypass can be considered. The patency rate of axillo-axillary bypass is often questioned. The aim of this study was to assess long-term outcomes of patients undergoing axillo-axillary bypass for subclavian or innominate artery stenosis (SAS) and to provide a literature overview. METHODS: In this single-center study, data from patients who underwent axillo-axillary bypass for symptomatic SAS between 2002 and 2018 were retrospectively analyzed. Bypass material was Dacron® (54%) or polytetrafluoroethylene (PTFE) (46%). Primary outcome was graft patency and secondary outcome was the occurrence of mortality and stroke. In addition, a systematic literature search was performed in MEDLINE and EMBASE databases including all studies describing patency of axillo-axillary bypass. RESULTS: In total, 28 axillo-axillary bypasses had been performed. Cumulative primary, primary-assisted, and secondary patency rates at one year were 89%, 93%, and 96%, respectively. Cumulative primary, primary-assisted, and secondary patency rates at five years were 76%, 84%, and 87%, respectively. The primary-assisted patency rates at five years for Dacron® and PTFE were 93% and 73%, respectively. A total of four primary axillo-axillary bypass occlusions occurred (14%), with a mean of 12 months (range, 0.4-25) after operation. The 30-day mortality was 7%; one patient died after a stroke and one died of a myocardial infarction. At the first postoperative follow-up control, 22 of the 26 remaining patients (85%) had relief of symptoms. The literature search included 7 studies and described a one-year primary patency range of 93-100% (n = 137) and early postoperative adverse events included death (range, 0-13%) and stroke (range, 0-5%). CONCLUSIONS: Patency rates of axillo-axillary bypasses for patients with a symptomatic SAS are good. However, the procedural complication rate in this series is high and attention should be paid to intervention indication.

Acute coronary syndrome following arteriovenous fistula creation in a post CABG patient: A steal phenomenon from coronary artery to subclavian artery.

A 70-year-old man with a history of coronary artery bypass grafting 15 years back and arteriovenous (AV) fistula creation in the left arm 1 month back presented with acute coronary syndrome (ACS). He had not received dialysis before his referral. We felt the most likely etiology for these complaints was increased cardiac oxygen demand from an increased cardiac output related to the newly formed left AV fistula. Coronary angiography was done to detect any significant stenosis in the native or grafted vessels. This revealed that the left subclavian artery was totally occluded in the ostioproximal segment and the coronary arteries did not have occlusions to explain the ACS setting. CT angiography confirmed the angiographic findings of the totally occluded left subclavian artery followed by a well-developed and patent left internal mammary artery to left anterior descending artery. This led to the consideration of a steal syndrome from the coronary artery by the subclavian artery distal to the occlusion. A successful percutaneous endovascular intervention on the left subclavian artery occlusion was performed. Subsequently, the patient became asymptomatic and experienced a dramatic increase in left ventricular ejection fraction.

Subclavian steal syndrome treated by kissing stenting of the subclavian and vertebral arteries.

The prevalence of subclavian artery (SA) stenosis is approximately 2%. The exact prevalence of extracranial vertebral artery (VA) stenosis is undetermined, with estimates ranging from 7% to 40%. Nearly 25% of ischaemic strokes involve the vertebrobasilar circulation, and arteriosclerotic disease and narrowing of the proximal VA may be the cause for up to one-fifth of these incidents. The bulk of SA stenoses occur proximally to the ostium of the VA. Vertebrobasilar ischaemia can be caused both by VA and SA stenosis. Surgical and endovascular approaches are potential treatment options for SA/VA stenosis. It has been demonstrated that endovascular intervention is considerably safer for this pathology, and with advances in device technology, angioplasty with stenting has become the preferred treatment option. We present the case of a 76-year-old man who presented with vertebrobasilar ischaemia from coexisting stenosis of the SA/VA which was treated by endovascular methods.

In-Situ Fenestration of a PTFE Thoracic Aortic Stent Graft for Delayed Left Subclavian Artery Revascularization Following Frozen Elephant Trunk Repair of Type A Aortic Dissection.

Left subclavian artery revascularization during endovascular repair of aortic dissection is often accomplished by left carotid-subclavian artery bypass or transposition. In situ fenestration of thoracic stent grafts provides an alternative method of revascularization without manipulation of the left carotid artery. We describe a case whereby in situ laser fenestration, combined with catheter-directed thrombectomy, was utilized to revascularize a thrombosed left subclavian artery following a frozen elephant trunk repair of type A aortic dissection. A 75-year-old male presented with pericardial tamponade and aortic insufficiency, secondary to type A aortic dissection. Patient underwent an emergent replacement of the aortic root, valve, arch, and ascending aorta in the frozen elephant trunk configuration. The innominate and left carotid arteries were revascularized with a bifurcated bypass graft from the ascending aortic graft. The left subclavian artery (LSCA) was covered with an antegrade deployment of a cTAG stent graft. During the immediate postoperative period, the patient was found to have a dissection of the left common carotid artery (LCCA) and pseudoaneurysm of the bypass graft anastomosis. The left carotid artery was replaced up to the proximal internal carotid. During rehabilitation, the patient developed left subclavian steal syndrome, with a CT angiography demonstrating thrombosis of the subclavian origin, and duplex ultrasound showing a reversal of the left vertebral flow. In order to revascularize the left subclavian artery without using the left carotid as the inflow, the in situ laser fenestration technique was planned. The vertebral artery origin was protected with a neuroclip through a supraclavicular incision. Through a brachial artery cutdown, a 9Fr flex sheath was positioned at the origin of the subclavian artery. A suction thrombectomy catheter was used to create a central channel in the thrombus. A 0.035″ 3.2 mm over-the-wire laser atherectomy catheter was used to create a fenestration through the cTAG stent graft. The subclavian branch stent was stented with an iCast balloon-expandable covered stent, excluding the mural thrombus. The patient recovered well with resolution of symptoms and was discharged home. Postoperative CT scan showed patent left subclavian branch stent and no endoleak across the fenestration of the aortic stent graft. Delayed laser in situ fenestration of a PTFE stent graft can be performed safely. The vertebral artery protection and catheter-directed thrombectomy are important adjuncts to reduce the risk of posterior stroke.

Endovascular Vertebral Artery Transposition Using Flow Reversal Technique for Left Subclavian Artery Stump Syndrome.

BACKGROUND: Cerebellar strokes are a rare complication related to thoracic endovascular aortic repair (TEVAR). This can manifest in an indolent manner or as a neurological catastrophe. Often it is unclear when a surgical intervention would be needed. Patients at risk for this relatively rare complication are not easily identified. CASE: We describe an endovascular option with flow reversal for left vertebral artery transposition using stent grafts for relocating arterial inflow and excluding a floating thrombus at the proximal subclavian artery (SCA) related to a previous TEVAR. CONCLUSIONS: Ligation of the subclavian artery proximal to the vertebral artery should be considered when performing a carotid subclavian bypass for elective TEVAR. This case details a unique, less invasive approach for vertebral artery transposition and thrombus exclusion in a high-risk patient with previous neck dissection.

Endovascular and Surgical Management of Subclavian Artery Occlusive Disease: Early and Long-Term Outcomes.

BACKGROUND: The aim of the study was to report early and late outcomes of surgical and endovascular management of subclavian artery atherosclerotic disease (SAAD). METHODS: Data about consecutive patients treated for subclavian artery atherosclerotic occlusive disease between 2001 and 2018 either by open surgical repair (OSR) or by endovascular repair (ER) were retrospectively collected and analyzed. Primary outcomes included 30-day death, as well as cardiac and neurologic events, reported separately for occlusion and stenosis. Secondary outcomes included primary patency in the long term, reported separately for occlusive and stenotic lesions. The Kaplan-Meier analysis with the logrank test was used to estimate long-term primary patency. Chi-squared and t-tests were used as appropriate to compare the outcomes of the 2 groups. A P value < 0.05 was considered statistically significant. RESULTS: Sixty-eight patients were treated using ER (49 patients) and OSR (19). Technical success rate was 100% in both groups. During in-hospital stay, 1 brachial hematoma and 2 acute upper limb ischemia occurred in the ER group and in the OSR group, respectively. At 30 days, no deaths or neurological/cardiac events were recorded in both ER and OSR groups. Symptoms resolution and upper limb salvage were 100% in both groups. In the ER group, primary patency was 100% at 7 years in patients who had been treated for stenotic lesions and 62.5 ± 21.3% in patients who had been treated for occlusive lesions (P = 0.0035). In the OSR group, primary patency was 100% at 7 years in patients treated for stenotic lesions and 25 ± 21.6% in patients who had been treated for occlusive lesions (P < 0.0001). Overall, long-term primary patency in the OSR group was 76.9 ± 11.7% at 7 years, being lower than that reported after ER (93.4 ± 4.5%, P = 0.02). CONCLUSIONS: Both ER and OSR proved to be safe, effective, and durable in the treatment of SAAD. In particular, the primary patency rates at long term for both ER and OSR showed better outcomes for stenotic lesions.

Case Report: An Unusual Presentation of Bilateral Subclavian Stenosis in a Patient with Asymptomatic Hypotension.

BACKGROUND Subclavian stenosis is an uncommon clinical condition associated with severe cardiovascular complications, usually presenting with claudication and subclavian steal syndrome. Here we describe the rare case of bilateral subclavian artery stenosis in an asymptomatic patient. CASE REPORT Our patient was a 63-year-old chronic smoker with no prior medical history whose chief complaint was dyspnea from an exacerbation of his chronic obstructive pulmonary disease (COPD). He was hypotensive with blood pressure 74/56 mmHg at admission, which raised suspicion for sepsis, adrenal insufficiency but the workup (renal panel, full blood count and synacthen tests) were normal. He quickly recovered after we treated his COPD exacerbation, but his hypotension persisted despite repeated fluid challenges. To evaluate for structural causes of his hypotension, we performed a full cardiovascular examination with 4 limb blood pressure measurements and found upper limb hypotension and lower limb hypertension. Subsequent imaging with ultrasound and computed tomography confirmed the presence of bilateral subclavian artery stenosis. Our diagnosis was thus bilateral subclavian artery stenosis secondary to atherosclerosis from chronic smoking. The patient was subsequently referred to vascular surgery for consideration of surgical revascularization. CONCLUSIONS Bilateral subclavian stenosis is extremely rare and requires a high index of clinical suspicion. Early diagnosis is important in the primary prevention of associated cardiovascular diseases.