Subclavian Artery Disease: Simulation Training Curriculum

Subclavian Artery Stenosis Etiology Incidence Clinical manifestations Diagnosis Indications Treatment Options - PTA - Surgical Technical Issues Complications Prognosis

Subclavian Artery Disease: Etiology Atherosclerosis Takayasu Arteritis Fibromuscular dysplasia Giant Cell Arteritis Radiation-induced Vascular Injury Thoracic Outlet Syndrome Neurofibromatosis

Subclavian Artery Atherosclerosis Most common cause of subclavian artery stenosis Predilection for the proximal part of the artery The occlusion usually extends from the aortic arch to the origin of the vertebral artery due to poor collateral circulation

Takayasu Arteritis Nonspecific inflammatory disease Primarily affects large arteries such as the aorta and its branches Includes both occlusive and aneurysmal disease Occlusive disease is more prevalent in Japan, the United States, and Europe Aneurysmal disease is more common in India, Thailand, Mexico, and Africa The prevalence is higher in women Median age of onset varies from 25 years in Asia and the United States to 41 years in Europe

Takayasu arteritis presenting with subclavian aneurysm Colvine et al Arthritis & Rheumatism (Add Year )54, 1: 382

The 1990 Criteria for Takayasu Arteritis1 1. Development of symptoms or findings related to Takayasu arteritis at age ≤40 years 2. Development and worsening of fatigue and discomfort in muscles of one or more extremities while in use, especially the upper extremities 3. Decreased pulsation of one or both brachial arteries 4. Difference of >10 mm Hg in systolic blood pressure between arms 5. Bruit audible on auscultation over one or both subclavian arteries or abdominal aorta 6. Arteriographic narrowing or occlusion of the entire aorta, its primary branches, or large arteries in the proximal upper or lower extremities, not due to arteriosclerosis, fibromuscular dysplasia, or similar causes; changes usually focal or segmental A patient shall be said to have Takayasu arteritis if at least three of these six criteria are present. The presence of any three or more criteria yields a sensitivity of 90.5% and a specificity of 97.8%. Arend et al Am College of Rheum 1990; 33 :1129–1134

Subclavian Artery Stenosis Etiology Incidence Clinical manifestations Diagnosis Indications Treatment Options - PTA - Surgical Technical Issues Complications Prognosis

Subclavian Artery Stenosis: Incidence Incidence of 0.5 - 2% 1 Left : Right = 3-4 : 1 ratio The stenosis is usually focal and in the proximal segment of the vessel Predictors: HTN Tobacco use Dyslipidemia Diabetes 1. Perrault et al, Ann Thorac Surgery 1993; 56: 927-30

Population Cohort (n = 2,885) The Incidence of Subclavian Stenosis in Population Cohorts and Clinical Cohorts1 Population Cohort (n = 2,885) Clinical Cohort (n = 1,227)† Prevalence (95% CI) 1.9% (1.4, 2.4) 7.1% (5.7, 8.7) Age <50 yrs 1.4% (0.6, 2.6) N/A Age 50–59 yrs 1.5% (0.8, 2.7) 4.3% (1.6, 9.0)‡ Age 60–69 yrs 1.7% (0.9, 2.9) 5.8% (3.8, 8.4) Age 70+ yrs 2.7% (1.7, 4.1) 8.7% (6.6, 11.1) 1 Subclavian stenosis was defined as an interarm systolic blood pressure of ≥15 mm Hg; † there was an insufficient sample size to determine the prevalence in ages <50 years; ‡ cohort C excluded individuals less than age 55. Shadman et al J Am Coll cardio 2004; 44:618-623

The Incidence of Subclavian Stenosis in Population and Clinical Cohorts Population Cohort (n = 2,885) Clinical Cohort (n = 1,227) Non-Hispanic White 2.3% 6.0% Hispanic 1.7% 10.5% Current or past smoker 2.2% 7.4% Ever diabetic 1.6% 8.0% Ever hypertensive 2.5% 8.5% PAD 10.1% 9.3% Ever had a stroke 8.7% Coronary Artery Disease 1.5% Shadman et al J Am Coll Cardiol 2004; 44:618-623

Subclavian Artery Disease Prevalence In Angiographic Studies 19% 6.8% 3.5% Pts with PAD Undergoing Cardiac Cath3 Cardiac Cath Pts1 CABG Pts Pts2 1English JE, CCI 2001;54:8 3Gutierrez GR, Angiology 2001;52:189 2Osborn L, CCI 2002;56:162

Subclavian Artery Stenosis Etiology Incidence Clinical manifestations Diagnosis Indications Treatment Options - PTA - Surgical Technical Issues Complications Prognosis

Subclavian Steal Syndrome The vertebral artery steals blood from the posterior cerebral circulation Stenosis of the subclavian artery or the brachiocephalic trunk proximal to the vertebral artery origin results in low-velocity and/or retrograde flow in the ipsilateral vertebral artery distal to the subclavian artery narrowing Wu C et al. Radiology 2005;235:927-933

Contrast-enhanced MR angiogram reveals lesion (arrow) responsible for subclavian steal syndrome is seen in left subclavian artery Bitar et al Am J Roentg 2004; 183:1840-1

Color MR Angiogram Retrograde flow in the left vertebral artery in a patient with a subclavian steal is shown in blue (arrows), indicating opposite flow direction. Note that the vertebral artery is red (arrowheads), indicating normal flow direction. Aoki et al Am J Neurorad 1998; 19:691-693

Subclavian Steal Syndrome Clinical Manifestations Arm claudication or hand numbness and a decrease of at least 20 mm Hg in blood pressure in the upper limb on the affected side Cerebral symptoms : dizziness, vertigo, and visual disturbances. In rare cases, cerebral ischemia may be present

Coronary - Subclavian Steal Syndrome Reversal of internal mammary artery flow (arrows) with left upper extremity activity Coronary Ischemia Takach et al Annal of Thoracic Surgery 2001, 71(1): 187-9

Angiographic Evidence of Coronary-Subclavian Steal Syndrome A, Angiography of the left coronary artery and LIMA in a right anterior oblique cranial projection. The figure is a composite of 2 images obtained during the same injection. The arrow points to the subclavian artery. B, Angiography of the left subclavian artery in an anterior-posterior projection. C,Angiography of the left subclavian artery in an anterior-posterior projection after stent placement. Vert indicates vertebral artery. Kroll et al Circulation. 2002;105:e184

Subclavian Artery Stenosis Etiology Incidence Clinical manifestations Diagnosis Indications Treatment Options - PTA - Surgical Technical Issues Complications Prognosis

Subclavian Artery Disease: Diagnosis Obstruction of the SA is suspected when there is a blood pressure difference > 20mm Hg between the two arms1 If there is a clinical suggestion of vasculitis: an erythrocyte sedimentation rate (ESR) or C-Reactive protein (CRP) should be measured2 Henry et al “Angioplasty and Stenting of the Carotid and Supra-Aortic Trunks” pg. 655-671. Grossmans “Catheterization” 7th Ed. pg. 573-575

Noninvasive Diagnostic Modalities: Duplex Ultrasonography Duplex ultrasonography of the subclavian artery and the vertebral artery can detect stenosis greater than 50% with a moderately high sensitivity (80% range) and an excellent negative predictive value (> 95%) Duplex ultrasonography is also highly useful in clinical follow-up of patients after revascularization procedures Kalaria et al J Am Soc of Echocard 2005, 18: 1107-1111

Normal subclavian artery Duplex waveform Abnormal subclavian artery duplex waveform showing elevated peak systolic velocity, spectral broadening, and loss of triphasic waveform. Kalaria et al J Am Soc of Echocard 2005, 18: 1107-1111

Noninvasive Diagnostic Modalities Diagnostic Imaging The diagnostic imaging work-up of patients should include: Magnetic resonance imaging (MRI) with or without arteriography (MRA) Computed tomographic (CT) scan of the brain with close evaluation of the posterior fossa and brainstream. Henry et al “Angioplasty and Stenting of the Carotid and Supra-Aortic trunks” pg. 655-671.

Coronal image from MR angiography of aortic arch and great vessels demonstrates occlusion (arrow) of the proximal left subclavian artery and a normal-appearing left vertebral artery (arrowhead) that originates from the left subclavian artery. Transverse image from MR angiography of the neck vessels, with a presaturation band placed above the volume of interest, shows normal signal intensity in the common carotid arteries (arrowheads) and right vertebral artery (long arrow). There is no signal in the left vertebral artery (short arrow), a finding that indicates either occlusion or retrograde flow Wu C. et al. Radiology 2005;235:927-933

Subclavian Artery Disease: Arteriography Ascending aortography Selective arteriography of supra-aortic vessels Kang WC et al. Circulation 2006;113:e735-737e

Severe Stenosis of Left Subclavian Artery Baseline Angiogram Post Stenting Arteriogram Queral R, Criado F J Vasc Surg 1996;23:368-75

Angiograms revealing total occlusions of both subclavian arteries

Subclavian Artery Stenosis Etiology Incidence Clinical manifestations Diagnosis Indications Treatment Options - PTA - Surgical Technical Issues Complications Prognosis

Indications for Revascularization Symptomatic ischemia of the posterior fossa Symptomatic subclavian steal syndrome Disabling upper extremity cludication Preservation of flow to LIMA/RIMA Preop coronary bypass surgery, where LIMA/RIMA will be used Postop CABG LIMA/RIMA with ischemia (with or without coronary-subclavian steal syndrome) Preservation of inflow to axillary graft or dialysis conduit “Blue-digit” syndrome (embolization to fingers) Inability to measure blood pressure Progressive stenosis or thromboembolus threatening cerebral blood supply Grossmans “Catheterization” 7th Ed. pg. 573-575.

Suclavian Artery Stenting for Blue Digit Syndrome Severe stenosis in the Left Subclavian, associated with 60-mm Hg reduction in left brachial cuff pressure and B. painful embolic ulcer at fingertip. C D C. Balloon angioplasty (PTA)/stenting performed via femoral approach using 85 cm long 7F sheath. Care used to avoid vertebral origin. D. Healed ulcer 2 months poststent. Grossmans “Catheterization” 7th Ed. pg. 573-575.

Indications for Revascularization in Asymptomatic Patients Angioplasty of the subclavian stenosis before other cardiovascular intervention and preservation of the vasculature for other angioplasty procedures Preservation of the cerebral perfusion. If other arterial lesions exist at the level of the supra-aortic vessels, to improve cerebral flow. Farina et al Am J Surg 1989; 58:511-14 Burke et al Radiology 1987; 164:699-704

Subclavian Artery Stenosis Etiology Incidence Clinical manifestations Diagnosis Indications Treatment Options - PTA - Surgical Technical Issues Complications Prognosis

Subclavian Artery Stenosis: PTA Percutaneous revascularization with balloon angioplasty followed by stent placement is the treatment of choice. Debries et al J Vasc Surg 2005; 41 (1) 19-23

Subclavian Artery Stenosis: Stenting Prevertebral Portion of Subclavian Artery Balloon expandable or self expanding stents with good radial force Postvertebral Portion of Subclavian Artery Self expanding stents to avoid possibility of postvertebral compression by extravascular structures at the thoracic outlet

Subclavian Artery Stenosis: Stenting of Ostial Subclavian

Subclavian Artery Stenosis: Stenting Left subclavian artery stenosis. a: Subclavian artery pre-stent. b: Stent placement. c: Repeat angiogram post-stent placement. Amor et al Cathet Cardiovasc Interv 2004; 63: 364-370

Indications for Covered Stents Aneurysm or “pseudoaneurysm” Traumatic artery injury Spontaneous arterial rupture or dissection Heuser R, Biamino G. Peripheral Vasc Stenting.2nd Ed. Pg:154

Subclavian Artery Stenosis: PTA Initial Success Rate Motarjeme A J of Endovascular Surgery 1996 3: 171–181

Associated Vertebral Artery Stenosis Kissing balloon technique Complication: brain embolization Cerebral protection devices, protection balloons, or filters could be used.

Subclavian Artery Stenosis: Surgery Carotid-subclavian bypass Aortosubclavian bypass Axilloaxillary bypass Revascularization of the subclavian artery using extrathoracic (carotid-subclavian) bypass. Takach et al Annal of Thoracic Surgery 2001; 71: 187-9

Subclavian Artery Stenosis Etiology Incidence Clinical manifestations Diagnosis Indications Treatment Options - PTA - Surgical Technical Issues Complications Prognosis

Subclavian Artery Stenosis Anticoagulation Premedication with Aspirin, with optional addition of clopidogrel Anticoagulation for a period of several weeks prior to revascularization in cases of Subclavian occlusion Grossmans “Catheterization” 7th Ed. pg. 573-575.

It is used at first intention in the majority of the cases Femoral Approach It is used at first intention in the majority of the cases

Subclavian Artery Stenosis Femoral Approach 8 Fr quiding catheter 0.035’’ steerable or hydrophilic guide wire 0.018’’ – 0.020’’ steerable guide wire Brachial approach Failure Surgery Success Adjacent to vertebral Artery 2 steerable guide wires (Vertebral 0.014’’, subclavian 0.018’’) Kissing balloon angioplasty Isolated stenosis Primary stenting Predilatation Good result Insufficient result Good result Insufficient result Stent Stent Henry et al “Angioplasty and Stenting of the Carotid and Supra-Aortic trunks” pg. 655-671.

Queral R, Criado F J Vasc Surg 1996;23:368-75.) Brachial Approach Recanalization of an occluded Subclavian artery (SA) When the occlusion begins at the ostium of the SA Severe tortuosity of the aorta Iliac and subclavian artery Bilateral occlusion of the iliac arteries Queral R, Criado F J Vasc Surg 1996;23:368-75.) Henry et al “Angioplasty and Stenting of the Carotid and Supra-Aortic trunks” pg. 655-671.

Subclavian Artery Stenosis After failure of FemoralApproach First Approach Brachial Approach 6 or 7 Fr long introduceur quiding catheter 0.035’’ steerable or hydrophilic guide wire 0.018’’ – 0.020’’ steerable guide wire Success Failure Primary stenting Predilatation Femoral Approach Good result Insufficient result Success Failure Stent Surgery Henry et al “Angioplasty and Stenting of the Carotid and Supra-Aortic trunks” pg. 655-671.

Subclavian Artery Stenosis Etiology Incidence Clinical manifestations Diagnosis Indications Treatment Options - PTA - Surgical Technical Issues Complications Prognosis

Subclavian Artery Stenting: Complications Hematomas Subclavian thrombosis Axillary artery thrombosis Stent Migration Arterial rupture Dissection Distal embolization Restenosis Neurologic complications Transient ischemic attack , stroke, hemiplegia, diplopia.

Arterial Rupture A B

Stent Migration

Thrombus

Dissection

Subclavian Artery Stenosis Etiology Incidence Clinical manifestations Diagnosis Indications Treatment Options - PTA - Surgical Technical Issues Complications Prognosis

Favorable Predictors Presence of subclavian steal syndrome : it prevents the risk of vertebral embolization 1 Isolatated stenosis Recurrent angina following an internal mammary coronary bypass 2,3 Hennerici et al Neurology 1988; 38: 669-673 Diethrich et al J Endovasc Surg 1995; 2: 77-80 Marques et al J cardiol 1996; 78: 687-690

Subclavian Artery Stenosis: Outcome Percutaneous transluminal angioplasty appears safe and efficient therapy for subclavian artery stenoses is not only an effective initial treatment, but also successful over the short- and long-term results.

Subclavian Artery Stenting: PTA Follow Up Immediate results (0-30 days)    Number at risk 89    Primary patency 88 98.88    Restenosis within 30 days 0 0.00    Deaths within 30 days 1 1.12 Midterm results (> 30 days to <2 years)    Number at risk 88    Primary patency 75 85.23    Restenosis 5 5.68    Deaths 8 9.09 Long-term results (> 2 years)    Number at risk 75    Primary patency 62 82.67    Restenosis 8 10.67    Deaths 5 6.67 Minimum observation time (months) 0.46 Maximum observation time (months) 109.43 Mean observation time (months) 36.12 ± 30.39 Bates et al Cath Cardiovasc Interv 2003; 61 (1):5-11

Cumulative Patency Cumulative patency was 89% at 40 months (n = 28), which is consistent with current literature. At 72 months, patency was 66% (n = 11); at 98.29 months, 57% (n = 1). Mean average follow-up time was 36.12 ± 30.39 months Bates et al Cath Cardiovasc Interv 2003 61 (1) Pages: 5-11

Patient Survival Time Cumulative patient survival (actual survival time) was 93% at 12 months (n = 65), 88% at 24 months (n = 47), 69% at 85 months (n = 8) and for the remainder of the 9-year follow-up Bates et al Cath Cardiovasc Interv 2003 61 (1) Pages: 5-11

Six months after the two stents were implanted, flow through the subclavian revascularization site is excellent; however, intimal hyperplasia has developed within the vertebral stent, although flow is not significantly hindered Henry et al J endovasc therapy 1999;6 (1): 33-41

Direct Stenting Vs. Predilatation Amor et al cath cardiovasc interv 2004; 63 (3): 364-370

Life Tables for All Patients Treated Without Stents in the Subclavian Artery Henry et al J endovasc therapy 1999;6 (1): 33-41

Life Tables for All Patients Treated With Stents in the Subclavian Artery Henry et al J endovasc therapy 1999;6 (1): 33-41