BC Vascular Surgery Day

Transcription

1 BC Vascular Surgery Day November 4,

2 Table of Contents Abdominal Aortic Aneurysm 3 4 Acute DVT 5 6 Peripheral Arterial Disease 7 9 Varicose Veins Diabetic Foot Ulcers Carotid Stenosis

3 Abdominal Aortic Aneurysm Indications for Repair Diameter greater than 5.5cm (male), 5cm (female) Growth rate greater than 1cm per year Symptomatic Definition Focal dilatation of abdominal aorta to 50% or greater than native diameter. Can be infrarenal, juxtarenal or pararenal. Advanced age Male Smoking Atherosclerosis Risk Factors Hypercholesterolemia Hypertension Coronary artery disease History of other vascular aneurysm Greater height Conservative Management For asymptomatic aneurysms smaller than size cut off for repair. Life style modifications smoking cessation Medical optimization Control of hypertension Control of hyperlipidemia Presentation Asymptomatic Symptomatic Flank pain, aneurysm tender to palpation Distal embolus Rupture Open repair Surgical Management Endovascular aneurysm repair (EVAR) 3

4 Complications Endoleak Stent migration Colonic ischemia Renal artery occlusion EVAR limb thrombosis Local wound complications in groin Overview of EVAR deployment 1. Arterial access through percutaneous puncture or cutdown in both groins to introduce sheaths 2. Patient is heparinized to prevent thrombosis during procedure 3. Wire and catheter access into aneurysm sac 4. Aortogram performed to evaluate location of renal arteries 5. Introduction and deployment of main body of stent graft just below lowest of the renal arteries 6. Wire cannulation of contralateral limb of stent graft 7. Angiogram to determine length and deployment location of limb graft on contralateral side based on location of internal iliac artery origin. 8. Deployment of properly sized stent graft 9. Angiogram to determine length and deployment location of limb on main body side (ipsilateral) 10. Deployment of ipsilateral stent graft 11. Ballooning of stent graft at proximal and distal sealing zones and overlapping stent grafts 12. Completion angiogram to determine patency of renal arteries and presence of endoleak What is an endoleak? Persistent blood flow into the aneurysm sac after EVAR repair. Epidemiology Found in up to 30-40% of patients intraoperatively Seen in 20-40% of EVARs during follow up Management Type I and III: Requires treatment Type II: watchful waiting as usually will spontaneously thrombose Type IV: Requires no treatment Type V: Controversial 4

5 Acute DVT Risk Factors Stasis o Surgery, trauma o Heart failure o Increased age o Anatomical abnormalities e.g. May-Thurner syndrome Vessel injury o Smoking o Previous DVT o Central venous catheterization Hypercoagulability o Malignancy o Cancer therapy o Estrogen therapy (OCP or HRT) o Inflammatory bowel disease o Myeloproliferative disease o Paroxysmal nocturnal hemoglobinuria o Thrombophilia Asymptomatic Presentation Calf pain or tenderness Swelling with pitting edema Erythema Superficial vein dilatation Homan's sign (sharp pain in calf on dorsiflexion of foot) Cyanosis and gangrene in severe cases Proximal DVT Distal DVT Diagnosis Well's criteria for pretest probability High risk patients require imaging o Duplex ultrasound is test of choice, but can miss proximal DVTs o If highly suspicious of DVT in setting of negative US should proceed to CT venogram or MR venogram Treatment Based on proximal vs distal location and provoked or not Medical o Anticoagulation for 3 months then reassess o Warfarin, DOAC, LMWH Interventional o Thrombolysis and thrombectomy for iliofemoral DVT o IVC filter for contraindication to anticoagulation 5

6 Clinical Pearl Proximal DVT o Superficial femoral vein is a deep vein and presence of a thrombus requires treatment as it is considered a DVT Distal DVT o If patient does not have any of the following risk factors, it is reasonable to follow with serial ultrasound without any anticoagulation Positive D-dimer Thrombosis close to proximal veins Thrombus >5cm in length Thrombus >7mm in diameter Involving multiple veins Active cancer History of previous VTE Inpatient * provided decision was made to anti-coagulate. + Anti-coagulate with LMWH. * 6

7 Peripheral Arterial Disease Introduction Insufficient blood supply to the extremities Most commonly as a result of atherosclerosis Risk factors o Smoking o Diabetes o Dyslipidemia o Hypertension o Age o Renal insufficiency Disease can be divided into inflow (aortoiliac) and outflow (infrainguinal) distribution Acute peripheral arterial occlusions can occur with or without a background of arterial disease Diagnosis Can be evaluated clinically by ABI, or with non-invasive or invasive imaging ABI Interpretation >1.3 Calcified vessels Normal Mild / asymptomatic Moderate / claudication <0.4 Severe / rest pain Non-invasive imaging duplex ultrasound, CT angiogram, MR angiogram Invasive imaging diagnostic angiogram Distinguishing between claudication and critical limb ischemia (ie. either rest pain or tissue loss) is crucial during evaluation 7

8 Management Clinical Pearl Conservative management o Antiplatelets o Control of hypertension, dyslipidemia, diabetes o Exercise o Smoking cessation Indications for surgery o Critical limb ischemia or severely disabling claudication o Angioplasty, endarterectomy, bypass surgery Angioplasty and stenting Key features can distinguish between vascular and neurogenic claudication o Characterization of pain Vascular consistent cramping Neurogenic inconsistent sharp, shooting, electric shocklike o Aggravating maneuvers Vascular pain does not begin until exercise Neurogenic pain begins as soon as patient stands up o Palliating maneuvers Vascular pain relief can be obtained while patient is still standing Neurogenic pain must be relieved by change of position (eg. sitting down or leaning forward) A note about ABI: normal ABI values do not exclude arterial disease, especially in diabetics Bypass Endarterectomy 8

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10 Varicose Veins Terminology Pathophysiology Chronic venous disorders Full spectrum of morphological and functional abnormalities of venous system Chronic venous disease When chronic venous disorders manifest as symptoms or signs indicating need for treatment Chronic venous insufficiency Patients with chronic venous disease with more advanced clinical signs Final common pathway is development of venous hypertension, resulting in abnormal diversion of venous flow from the deep to the superficial system Dysfunction of venous valves usually directs flow from distal to proximal, and from superficial to deep above the foot Overdistension of superficial venous system o Interstitial fluid accumulation o Formation of subcutaneous panniculitis Diagnosis Venous reflux on duplex ultrasound Extent of reflux may be any combination of superficial, perforator, or deep 10

11 Treatment Conservative Elevation of legs, exercise, avoidance of prolonged standing Compression stockings Wound care for ulcers Procedural Surgical excision vein ligation/stripping, phlebectomy Sclerotherapy sodium tetradecyl sulfate, hypertonic saline Thermal Radiofrequency ablation Laser ablation Cyanoacrylate glue Clinical Pearls Which varicose veins bleed? Telangiectasia, reticular veins, or varicose veins that are superficial or near bony prominences How to stop a bleeding varicosity? Elevate leg Local pressure Suture Long-term management Stockings Assess for incompetent valves Treatment based on ultrasound in a top-down fashion o Presence of reflux increases recurrence rates of telangiectasia and reticular veins that have been treated 11

12 Diabetic Foot Ulcers Etiology Combination of peripheral neuropathies Motor: weakness and atrophy of foot muscles leading to deformities and altered biomechanics Sensory: loss of protective sensation (pressure, pain, temperature) Autonomic: hyperemic blood flow leads to increased inflammation and bone reabsorption Approach to management of DFUs Local ulcer care Debridement Wound dressing Antimicrobial properties NPWT for extensive open wounds, providing there is no residual necrotic tissue or infected bone Mechanical offloading Contact casts eliminates pressure points by providing contact at all points Cast walkers brace designed to maintain contact fit Therapeutic shoes wedge shoes, rocker sole shoes Surgical correction of anatomic deformities Consideration of revascularization Control of infection Assessment Sensation 10g monofilament 128Hz tuning fork Vasculature Palpation of peripheral pulses Measurement of ABI and TBI Diabetics tend to have macrovascular disease that is infrapopliteal, microvascular disease in the feet, and calcified vessels Infection 12

13 Clinical Pearl Ulcer etiology can be very difficult to establish, and may be multifactorial ABI measurements are often unreliable in diabetic patients due vessel wall calcification. 13

14 Carotid Stenosis The presence of atherosclerotic plaque in the carotid vessels. Diagnosis Carotid duplex ultrasound CT angiogram of arch to vertex The Carotid Bruit Risk Factors Hypertension Smoking Diabetes Dyslipidemia Family history Advanced age Meta-analysis of symptomatic and asymptomatic patients showed sensitivity and specificity for 70-99% stenotic lesion to be 53 and 83% Screening not recommended in asymptomatic carotid bruits without other risk factors Indications for surgery Society of Vascular Surgeons recommend Presentation Symptomatic stenosis greater than 50% o Greater benefit in higher degree of stenosis (>70%) Asymptomatic stenosis greater than 60% Symptomatic TIAs (< 24 hours) o Amaurosis fugax o lateralizing neurological symptoms Stroke Asymptomatic Found incidentally on imaging Operative Procedures Carotid endarterectomy Carotid stenting 14

15 Ultrasound criteria Combines measured blood flow velocities and calculated ratios to determine degree of stenosis There are different criteria generated by different studies o NASCET criteria o Society of Radiologists in ultrasound (shown above) o European Carotid Surgery trial criteria Carotid Endarterectomy Plaque removal via a neck incision At our centre, carotid shunting is performed based on presence of EEG changes indicating decreased cerebral perfusion o Shown here are different types of shunts available for use 15