VASCULAR. Mark R. Nehler Associate Professor Vascular Surgery UCHSC UCHSC

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1 VASCULAR Mark R. Nehler Associate Professor Vascular Surgery

2 Vascular 101 Topics to Cover General wisdoms Basic Data for decisions Carotid disease Aortic Aneurysm Acute limb ischemia

3 Vascular 101 Common things are common, but Old Patients Atherosclerosis Young Patients Hypercoaguable Vasculitis Trauma

4 Vascular 101 You can t t make an asymptomatic patient feel better Carotid disease Aneurysms You have to know the natural history of disease to recommend therapy

5 Vascular 101 You only need 6 patients for a vascular fellowship Repeat procedures are common Old records helpful Dr Peyton is the master at this

6 Vascular 101 Vascular traditionally has not had a companion medical specialty Vascular medicine Many referrals Delays Do not have any vascular problem

7 Vascular 101 Dude, I want to do big aortas * Frequent chief desire More important Basic understanding of major components Learn to use the instruments Understand basic exposures *Forrest Sheppard

8 Vascular 101 Balloons are for clowns Maybe so, but currently 60-70% of the standard vascular practice is endovascular Turf issues Fragmentation of care/message Expensive *Tom Whitehill

9 Anderson et al. J Vasc Surg 2004;39:1200-8

10 Vascular 101 Surprises are for birthday parties* Preoperative imaging Plans A, B, and C *Robert McIntyre

11 Vascular 101 Few things are as unreliable as a palpable pedal pulse Its either obvious, or its not there No range of 1-4+ Sensitivity 30-60% False positive 20% Ann R Coll Surg Engl May;74(3): World J Surg Mar;23(3): Ann R Coll Surg Engl May;74(3):166-8

12 Vascular 101 Let s s get noninvasive studies Frequently not necessary Frequently not understood Despite that, frequently the plan

13 Vascular 101 Diagnostic Tools Pulse exam ABI PVRs and digital pressures Duplex CT Angiography MRA

14 Vascular 101 ABI (ankle brachial index) Highest brachial blood pressure either arm Highest ankle blood pressure single leg Dorsalis Pedis Posterior Tibial Highest ankle pressure/highest brachial pressure

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16 Vascular 101 ABI rules of thumb Claudication CLI <0.5 Calcified vessels in up to 20% PVRs Toe Pressures - >70 good, < 50 bad

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20 Vascular 101 In house consult role In house consult role Stop the bleeding Remove the foreign body Bad feet in ER Non healing ulcers on extremities Phlebitis infection Acute ischemia Carotid findings

21 Vascular 101 Clinic Role Clinic Role Swollen limbs Carotid disease AAA Painful limbs (some actually have PAD) Dialysis access Varicose veins Non healing wounds on extremities

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23 Carotid Strokes 500,000 per year in the United States Carotid artery disease: 20% Symptoms TIA hemispheric or retinal Dizziness/Syncope not a carotid symptom

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26 ICA Normal 1-19% 19% 20-59% 60-79% 80-99% Carotid Velocities PSV<125 PSV<125 PSV<125 PSV>125, EDV<125 EDV>125 Spectral Broadening No Limited Yes Yes Yes

27 Carotid US Randomized Trials Symptomatic NASCET Trial 659 pts 70-99% At 2 years (stopped early) Surgery 9% stroke Medical 26% stroke NEJM 1991;325:

28 ACST Multicenter randomized trial CEA vs ASA asymptomatic patients 88% surgery group CEA in one year 3.4 year mean followup 126 sites in 30 countries Lancet 2004:363:

29 ACST CEA 1560 patients 2.8% 30 day stroke/death 112 not performed at one year 31 LFU Nonoperative 1560 patients 201 had CEA in 5 years 4.5% 30 day stroke/death 37 LFU

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31 Carotid Carotid Stenting Currently only approved for symptomatic disease (Medicare will pay for) Asymptomatic disease has to be in an approved registry with high risk criteria Multiple trials ongoing Given the state of healthcare budget not likely to change

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38 AAA General AAA definition: >50% increase in aortic diameter Normal male aorta 2 cm Incidence 1.5% autopsy 3.2% population screening 5% CAD screening 10% PAD screening

39 AAA Iliac Aneurysms Defined as >1.5 times normal diameter Basically cm in diameter 70% involve the common, remainder the internal 90% of iliac aneurysms associated with AAA 10-20% AAAs have associated iliac aneurysms

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42 AAA Multiple aneurysms Only 3-4% of AAA patients have peripheral aneurysms 40% of popliteal aneurysm pts have AAA 50-90% of femoral aneurysm pts have AAA 25% of thoracic aneurysm pts have AAA 3-8% of pts after AAA repair will develop aneurysm of proximal aorta

43 AAA Etiology AAA Elastin primary aortic load-bearing element Decreases as move proximal to distal Increased pulsatility at bifurcation Decreased vasa vasorum in infrarenal aorta

44 AAA Etiology AAA Degradation of aortic media Imbalance between proteolytic enzymes/inhibitors Increased expression/activity of matrix metalloproteinases in AAA walls

45 AAA Etiology AAA Familial 15-20% of AAAs Increased risk of rupture Abnormal type III collagen Screen first degree relatives>50 years 30% incidence of AAAs

46 AAA Diagnosis Majority discovered during imaging studies for other reasons Physical exam Aortic bifurcation at the umbillicus Pulsatile mass in epigastrium No good in obesity Overcall a tortuous normal aorta in very thin

47 AAA AAA Screening US is the best exam Measurement accurate within 3 mm Does not provide adequate detail to plan operation

48 AAA AAA expansion rates AAA expansion rates 2-4 mm per year 15-20% of AAAs do not change over time Rate of expansion variable Risk factors Uncontrolled hypertension COPD Familial Post cardiac transplant

49 AAA Ruptured AAA Half unknown prior to rupture Sudden abdominal pain 82% Classic triad (in only 50%) Abdominal/back pain Hypotension Pulsatile mass

50 AAA Ruptured AAA 50% die prior to hospital 50% arrive to hospital 25% of these die prior to OR Operative mortality for ruptured AAA 40-75% Potentially reduced with endovascular approach to controlling aorta

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55 AAA ADAM data Randomized AAAs cm Early surgery 569 Observation 567 Mean followup 4.8 years

56 AAA ADAM data Immediate repair 93% had repair Surveillance group 61% had repair None due to rapid expansion 27% of baseline cm 53% of baseline cm 81% of baseline cm NEJM 2002;346:

57 AAA ADAM data Excellent followup (only 9 pts LFU) 10 surveillance patients ruptured (0.6%/year) 20 had repair for pain without rupture Overall operative mortality 2.7% 0.6% in the immediate operation group

58 AAA ADAM data Despite the low operative mortality No benefit from early repair More than half of the surveillance patients eventually had surgery

59 AAA ADAM Large Aneurysm data 198 patients with AAA >5.5 cm followed 1 year probable AAA rupture rates 9.4% AAA % AAA % AAA >7.0 cm JAMA 2002;287:

60 AAA Aortic endografts Neck diameter/angulation (23-31 mm) Length from renals (15 mm) Iliac diameter/aneurysmal disease (10-20 mm) Access (12-18 Fr sheath) Renal function Age/need for CT followup

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64 AAA Endoleaks Type 1 lack of seal at ends Type II lumbars or IMA Type III Fracture of components

65 Acute Limb Ischemia Symptoms 5 p s Pallor Pulselessness Pain Paresthesia Paralysis

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67 Acute Limb Ischemia Categories of Severity Category I Viable Resolving pain/paresthesia No current motor/sensory defects J Vasc Surg 1986;4:80-94

68 Acute Limb Ischemia Categories of Severity Category IIa Salvageable Minimal sensory defects No motor defects Pain limited to the foot J Vasc Surg 1986;4:80-94

69 Acute Limb Ischemia Categories of Severity Category IIb Salvageable but needs immediate therapy Sensory changes in the foot Motor changes in the toes Severe foot pain + calf pain J Vasc Surg 1986;4:80-94

70 Acute Limb Ischemia Categories of Severity Category III Major tissue loss/nerve damage inevitable Profound motor and sensory defects Possible calf rigidity J Vasc Surg 1986;4:80-94

71 Acute Limb Ischemia Practical irreversible markers Fixed cyanosis Rigor of the calf Contracture Mottling

72 Acute Limb Ischemia Practical points Condition of the femoral pulses important Therapy requires senior level judgment Often will get CTA aorta and runoff

73 Categories of Acute Limb Ischemia on Presentation 10% 45% 45% Category I Viable Category II Threatened Category III Nonviable* Eliason et al., 2003; Kuukasjarvi et al., 1994 Ouriel et al., 1994; Ouriel et al., 1998

74 Etiologies of Acute Limb Ischemia 4% 3% 40% 38% 15% Native thrombosis Embolism Peripheral aneurysm Reconstruction thrombosis Trauma (including iatrogenic) Cochrane Database Syst Rev 2002:CD Br J Surg 1998;85:

75 Presentation Timing in Acute Limb Ischemia 100 Trauma 80 Peripheral Aneurysm Native Thrombosis 20 Reconstruction Thrombosis 0 Early Presentation Later Presentation Embolism

76 Acute Ischemia Emboli distribution Cerebral 20% Visceral 10% Peripheral 70% Ann Vasc Surg 1991;5:96

77 Acute Ischemia Peripheral Emboli 15% 10% 40% 15% 20% Aorta Iliac Femoral Popliteal Upper Ann Vasc Surg 1991;5:96

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80 Acute Ischemia Immediate anticoagulation Prevent thrombus propagation Mild vasodilation Large bolus and drip

81 Acute Limb Ischemia Percutanous mechanical thrombectomy Hydrodynamic recirculation Dissolution of the thrombus occurs within an area of continuous mixing referred to as the "hydrodynamic vortex Selectively traps, dissolves, and evacuates the thrombus Amplatz, Hydrolyser, and Angiojet

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84 Acute Limb Ischemia Percutaneous mechanical thrombectomy Only useful in vessels > 3 mm Hemolysis is an issue 8 minutes in stagnant vessel 4 minutes in vessel with flow

85 Acute Limb Ischemia Advantages of combined technique Reduction in thrombolytic dosage Reduction in thrombolytic duration Reduction in bleeding complications

86 Acute Limb Ischemia Major complications Bleeding Limb loss Compartment syndrome Renal failure

87 Acute Limb Ischemia Bleeding 10-15% requiring transfusion Reduced with combo methods Increases with duration/dose Want resolution by hours Access site issues important Prior grafts Obesity

88 Acute Limb Ischemia Major amputation Incidence is up to 25% 10-15% of patients thought to be salvageable 10% of patients present unsalvageable

89 Acute Limb Ischemia Major amputation More frequently complicated by bleeding Calf muscle is usually compromised Ratio of AKA/BKA is 4/1 Psychological issues

90 Acute Limb Ischemia Compartment syndrome Symptoms/findings Extreme pain Edema Paresthesias Compartment pressures mm Hg worrisome >30 mm Hg clear indication

91 Acute Ischemia Fasciotomy Incidence 5-25% Superficial posterior compartment Deep posterior compartment Take down the soleus Release the fascia posterior to this Anterior compartment Lateral compartment

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94 Acute Limb Ischemia Rhabdomyolysis Laboratory evidence myoglobinuria 20% Acute renal failure Half of patients with CPK>5000 Urine myoglobin >20 mg/dl

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96 Acute Limb Ischemia Rhabdomyolysis Physiology Tubular obstruction by myoglobin precipitates Tubular necrosis due to lipid peroxidation Renal vasoconstriction exacerbated by fluid shifts

97 Acute Limb Ischemia Rhabdomyolysis Treatment Hydration Alkalinizing the urine Eliminating the source of myoglobin No benefit from Mannitol Plasmaphoresis

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