Impact of Non-Invasive Diagnostic Methods on Therapeutic Indications in Vascular Diseases
Palermo 2009 lecture discusses how non-invasive methods have altered decisions on surgical treatments, especially based on duplex scanning evaluations.
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1. Palermo 2009 Palermo 2009 P.L. Antignani Dept. of Angiology, (Director: C. Allegra) s.Giovanni Hospital, Rome, Italy Non invasive diagnostic methods: how have they modified the therapeutical indications?
2. The non invasive diagnostic methods have modified our therapeutical decision in several vascular diseases. Particularly, many forms of surgical treatment, both endovascular and open, are performed based exclusively on evaluation with duplex scanning.
3. We discuss the main conditions in which this change is more evident: Carotid stenosis Abdominal aortic aneurysm Deep venous thrombosis Superficial venous thrombosis Chronic venous insufficiency
4. Definition of carotid lesion Investigation techniques High-resolution B-mode imaging Color Doppler flow imaging Power Doppler imaging Compounded imaging Four-Dimensional ColorDoppler flow imaging Contrast ultrasonic agents Transcranial Doppler IVUS Spiral CT scan Contrast-enhanced MR angiography Diffusion weighted MR imaging (DWI)
5. A carotid color flow duplex scanning allows: to quantify the stenosis to assess its morphological characteristics
6. Evaluation of stenosis Evaluation of stenosis Degree of stenosis in diameter Degree of stenosis in diameter Degree of stenosis in Degree of stenosis in cross-sectional area cross-sectional area Evaluation of velocity Evaluation of velocity
7. Degree of stenosis Degree of stenosis
8. Color Flow Duplex imaging CAROTID PLAQUE THICKNESS THICKNESS ECHOGENICITY ECHOGENICITY STRUCTURE STRUCTURE SURFACE SURFACE mm mm REGULAR IRREGULAR REGULAR IRREGULAR HOMOGENEOUS HETEROGENEOUS HOMOGENEOUS HETEROGENEOUS HYPOECHOIC HYPERECHOIC HYPOECHOIC HYPERECHOIC
9. Plaque Classification Plaque Classification • Type I (uniformly echolucent) • Type II (predominately echolucent) • Type III (predominately echogenic) • Type IV (uniformly echogenic) • Type V (heavy calcification) Color flow duplex imaging
10. Carotid plaque and Risk of stroke Carotid plaque and Risk of stroke Other criterion: PLAQUE MORPHOLOGY Other criterion: PLAQUE MORPHOLOGY Structure Structure Fibrous cap Fibrous cap Intraplaque hemorrhage, surface ulceration, rupture Intraplaque hemorrhage, surface ulceration, rupture
11. Morphology of plaque Morphology of plaque “ The higher the degree of stenosis, the more likely it is associated with ultrasonic heterogeneous and hypoechoic plaque ” ( MM Sabetai, J Vasc Surg 2000) ( MM Sabetai, J Vasc Surg 2000)
12. Diagnosis of presence and grading of carotid stenosis Colour-flow duplex scanning is the investigation of choice for the diagnosis and measurement of carotid stenosis, provided that objective criteria are used, by experienced operators. Colour-flow duplex scanning is the investigation of choice for the diagnosis and measurement of carotid stenosis, provided that objective criteria are used, by experienced operators. The velocities detected should be mentioned in the report as well as whether the percent stenosis reported refers to the angiographic ECST or NASCET method. Guidelines of ISVI Guidelines of ISVI and ACC- AHA-EVES and ACC- AHA-EVES
13. Plaque characteristics Surface ulceration, low GSM (<25), heterogeneous appearance of the plaque and the juxta-luminal location of the echolucent area after image normalisation are ultrasonographic indicators of plaque vulnerability and should be considered in the selection of appropriate therapy and the frequency of follow up Surface ulceration, low GSM (<25), heterogeneous appearance of the plaque and the juxta-luminal location of the echolucent area after image normalisation are ultrasonographic indicators of plaque vulnerability and should be considered in the selection of appropriate therapy and the frequency of follow up . Carotid Stenosis 50 % GSM 17 Guidelines of ISVI Guidelines of ISVI and ACC- AHA-EVES and ACC- AHA-EVES
14. A carotid color flow duplex scanning allows to evaluate in the follow up: surgical results the restenosis the efficacy of medical treatment
15. Angio CT/MR allow to evaluate: Cohexisting aortic arch lesions Intracranial vessels anatomy Avoiding angiography
16. before after Diffusion-weighted magnetic resonance imaging (DWI) allows a fast evaluation of ISCHEMIC LESIONS
17. Transcranial color Doppler can be used before CE/CAS to evaluate: Cohexisting lesions of intracranial vessels Circle of Willis efficiency Intracranial haemodynamic effects of extracranial carotid lesions Cerebrovascular reserve Microembolic events due to ulcerated plaques Crossclamping risk and indication for shunting INDICATION FOR SURGERY IN ASYMPTOMATIC SUBJECTS OR IN PATIENTS WITH BILATERAL CAROTID LESIONS
18. Surgical indications CE could be better in patients with: Long multifocal lesions Echolucent plaque Severe ulceration Heavy circumferential calcifications of carotid bifurcation Severe tortuosities Extensive aortic or brachiocephalic trunk lesions If a clot is suspected
19. ‘91-’93 ’94 ’95 ’96 ’97 ’98 ’99 ’00 -’04 ’05-’07 ys Carotid surgery without angiography Experience of Dept. of Vascular Surgery – La Sapienza University (prof. F. Benedetti Valentini – B. Gossetti) 1991-2007 Angiography Without angiography 100 100 80 60 40 20 % 94.5 5.5 79.1 20.9 64.1 35.9 36.4 63.6 19.1 80.9 15.0 85.0 10.3 89.7 8.3 91.7
21. Abdominal aortic aneurysm Among asymptomatic patients, ultrasound detects the presence of an abdominal aortic aneurysm accurately, riproducibly an at low cost. Sensitivity and specificity approach 100 %. Ultrasound is ideal for screening and in determination of aneurysm growth rate. A growth rate of > 0,7 cm per sex months or 1 cm per years has been suggested as a threshold for proceeding to surgery, irrespective of size. Chaikof EJ et al: The care of patients with abdominal aortic aneurysm: the Society for Vascular Surgery practice guidelines. J. Vasc. Surg. 2009;50 suppl October: 8S
22. Morphology: Endovascular wall thrombus Ulceration and calcification “ true ” vessel lumen Size and longitudinal extension Color flow duplex imaging
23. Color flow duplex imaging Hemodynamics Decrease of flow velocity Color: “ mosaic ” immaging
24. Color flow duplex imaging Acute conditions: Wall dissection Wall rupture Rapid growth Acute thrombosis
25. Follow up of endovascular treatment Position and patency of endograft Diameters and pulsatility of aneurysm Endoleak (sensitivity 81-100 %, specificity 74-99 %) Patency of other vessels Infections Fistulas
27. VTE and symptoms VTE and symptoms Each of these stages of Venous Thromboembolism (calf DVT, proximal DVT, PE) may or may not be associated with symptoms. Each of these stages of Venous Thromboembolism (calf DVT, proximal DVT, PE) may or may not be associated with symptoms. The development of symptoms depends on the extent of thrombosis, the adequacy of collateral vessels, and the severity of associated vascular occlusion and inflammation. The development of symptoms depends on the extent of thrombosis, the adequacy of collateral vessels, and the severity of associated vascular occlusion and inflammation. For the diagnosis and monitoring of VTE the clinical findings are useful but inadequate (accuracy no more than 30 %). For the diagnosis and monitoring of VTE the clinical findings are useful but inadequate (accuracy no more than 30 %).
28. DEEP VENOUS THROMBOSIS DEEP VENOUS THROMBOSIS Diagnosis and monitoring Diagnosis and monitoring CLINICAL DIAGNOSIS: inadequate CLINICAL DIAGNOSIS: inadequate VENOGRAPHY: gold standard (?) VENOGRAPHY: gold standard (?) DUPLEX SCANNING: high accuracy DUPLEX SCANNING: high accuracy COLOR-FLOW IMAGING: NEW GOLD STANDARD COLOR-FLOW IMAGING: NEW GOLD STANDARD PLETHYSMOGRAPHY: complementary PLETHYSMOGRAPHY: complementary (quantitative evaluation) (quantitative evaluation)
29. Colour Flow Duplex Scanning can provide both Colour Flow Duplex Scanning can provide both morphologic and haemodynamic findings and morphologic and haemodynamic findings and represent now a quick and non-invasive represent now a quick and non-invasive alternative method of diagnosing deep vein alternative method of diagnosing deep vein thrombosis in the lower limbs. thrombosis in the lower limbs. Colour Flow Duplex Scanning Colour Flow Duplex Scanning
30. Colour Flow Duplex Scanning Colour Flow Duplex Scanning Colour Flow Duplex Scanning represents a valid clinical tool, not only for the initial diagnosis of DVT but also to assess long-term outcome of thrombus. Colour Flow Duplex Scanning represents a valid clinical tool, not only for the initial diagnosis of DVT but also to assess long-term outcome of thrombus. This test can guide initial patient management, providing information about clot attachment to the vein wall and resolution. This test can guide initial patient management, providing information about clot attachment to the vein wall and resolution. In addition, it can identify those patients with a potential high risk for post-thrombotic syndrome . In addition, it can identify those patients with a potential high risk for post-thrombotic syndrome . Finally, CFDS may be used to compare and evaluate the results of different regimens of anticoagulant and fibrinolytic drug therapy on the long-term outcome of venous thrombi in the lower extremity. Finally, CFDS may be used to compare and evaluate the results of different regimens of anticoagulant and fibrinolytic drug therapy on the long-term outcome of venous thrombi in the lower extremity.
32. Compression manouvre Accuracy 100 %
34. CHARACTERISTICS OF THE THROMBI CHARACTERISTICS OF THE THROMBI AND INCIDENCE OF PULMONARY EMBOLISM AND INCIDENCE OF PULMONARY EMBOLISM (354 patients with DVT -28.5%- out of 1238 cases with suspected DVT) (354 patients with DVT -28.5%- out of 1238 cases with suspected DVT) cases PE - free-floating thrombi: 40 (11,2%) 25 (60.2%) ( ----> 2 cm) - “ cutted ” thrombi: 81 (22.8%) 81 (100%) - “ peduncle ” thrombi: 5 ( 1,4%) 5 (100%) (free head in venous confluence) - “ moving ” thrombi: 2 ( 0.5%) 2 (100%) (only fixed base) - adhered thrombi: 226 (63.8%) 35 (15.4%) - adhered thrombi: 226 (63.8%) 35 (15.4%) WFUMB 2000 WFUMB 2000
35. LOCALIZATION OF THE THROMBI LOCALIZATION OF THE THROMBI AND INCIDENCE OF PULMONARY EMBOLISM AND INCIDENCE OF PULMONARY EMBOLISM ( 354 patients with DVT - 28.5%- out of 1238 cases with suspected DVT) ( 354 patients with DVT - 28.5%- out of 1238 cases with suspected DVT) DVT EP % m EP f EP DVT EP % m EP f EP -iliac+inferior cava v. 35 19 54.2% 24 14 11 5 -iliac+inferior cava v. 35 19 54.2% 24 14 11 5 -femoral+ex. iliac v. 144 52 36.1% 77 32 67 20 -femoral+ex. iliac v. 144 52 36.1% 77 32 67 20 -popliteal+femoral v. 107 6 6 61 . 6 % 65 40 42 26 -popliteal+femoral v. 107 6 6 61 . 6 % 65 40 42 26 -popliteal v. 18 6 33.3% 9 5 9 1 -popliteal v. 18 6 33.3% 9 5 9 1 -gastrocnemious v. 34 4 11.7% 7 - 32 4 -gastrocnemious v. 34 4 11.7% 7 - 32 4 -long saphenous v. 16 5 31.2% - - 16 5 -long saphenous v. 16 5 31.2% - - 16 5 Antignani PL, WFUMB, 2000
36. The presence of an antiphospholipid antibody (lupus anticoagulant or anticardiolipin antibody) is associated with a 2-fold increase in risk of recurrent VTE. Deficiencies of antithrombin, protein C, and protein S, homozygous factor V Leiden and elevated levels of homocysteine and coagulation factor VIII (> 234 IU/L) have also been associated with higher recurrence rates. Heterozygous forms of factor V Leiden and the G20210A prothrombin gene mutation confer relatively little increased risk of recurrent VTE. (Kryle P. et al. N Engl J Med 2000; Eichinger S et al. Thromb Haemost. 1999; Miles JS et al. J Am Coll Cardiol. 2001; Simioni P et al. Blood 2000) Monitoring of coagulative factors Risk of Recurrent VTE Risk of Recurrent VTE
37. Risk of recurrent VTE Risk of recurrent VTE Although not predictive of the location of thrombosis, the risk of recurrence is greater when anticoagulants are stopped while there is still evidence of residual DVT on ultrasound imaging . Although not predictive of the location of thrombosis, the risk of recurrence is greater when anticoagulants are stopped while there is still evidence of residual DVT on ultrasound imaging . Recurrent DVT may be caused by a disturbed balance between propagation and thrombus regression. Recurrent DVT may be caused by a disturbed balance between propagation and thrombus regression. Recurrent DVT was reported in 17% of the patients after 2 years. Recurrent DVT was reported in 17% of the patients after 2 years. (Kearon C. Clin Chest Med. 2003; Heit JA et al. Arch Intern Med. 2000) (Kearon C. Clin Chest Med. 2003; Heit JA et al. Arch Intern Med. 2000) Monitoring with ultrasound Monitoring with ultrasound
38. About 60 % of patients with the history at one episode of proximal deep vein thrombosis develop post-thrombotic syndrome within two years . About 60 % of patients with the history at one episode of proximal deep vein thrombosis develop post-thrombotic syndrome within two years . Compression stockings have reduced this rate by about 50 %. Compression stockings have reduced this rate by about 50 %. The post-thrombotic syndrome is strongly related to recurrent ipsilateral deep vein thrombosis. The post-thrombotic syndrome is strongly related to recurrent ipsilateral deep vein thrombosis. monitoring of deep venous system with ultrasound monitoring of deep venous system with ultrasound Post-thrombotic syndrome after DVT Post-thrombotic syndrome after DVT
39. Post thrombotic syndrome Instrumental evaluation Post thrombotic syndrome Instrumental evaluation The pathophysiology of PTS is not entirely understood. The pathophysiology of PTS is not entirely understood. Factors that are probably important in the development of PTS are venous reflux, deep vein obstruction and calf muscle pump dysfunction. Factors that are probably important in the development of PTS are venous reflux, deep vein obstruction and calf muscle pump dysfunction. The presence and location of The presence and location of venous reflux and obstruction venous reflux and obstruction can be measured with ultrasound can be measured with ultrasound with high accuracy . with high accuracy .
40. Differential diagnosis Venous popliteal aneurysm Neoplasia in inferior cava vein
42. Superficial venous thrombosis Extension and involvement Clinical assessment underestimates the thrombus
43. Superficial venous thrombosis …is estimated like a thrombus on risk if its distance from SF-J is 2 cm (guidelines by Italian Society for Vascular Investigation - 2007): Treatment of SVT as DVT.
44. Murgia AP et al: Int Angiol. 1999 Dec;18(4):343-7. Surgical management of ascending saphenous thrombophlebitis . METHODS: We retrospectively reviewed 146 patients referred to our Vascular Laboratory for acute superficial thrombophlebitis from 1987 to 1997. Duplex scanning identified 85 cases of superficial thrombophlebitis involving at least a segment of the saphenous vein localized below the knee (58.2%); 37 of thrombophlebitis extending into both the superficial and deep venous systems (25.3%) and 24 of saphenous thrombosis extending to within 5 cm of the saphenofemoral junction (16.4%). The latter group underwent saphenofemoral disconnection. CONCLUSIONS: Duplex scanning showed 100% accuracy both in determining the presence of thrombosis and its extent. Saphenofemoral disconnection for thrombosis involving the saphenofemoral junction is a safe procedure and can be performed on an outpatient basis.
46. Deep venous thrombosis after radiofrequency ablation of greater saphenous vein: a word of caution. Hingorani AP et al. PURPOSE: Radiofrequency ablation (RFA) of the greater saphenous vein (GSV; "closure") ……… potentially lethal complication, deep venous thrombosis (DVT). Seventy-three lower extremities were treated…. All patients underwent venous duplex ultrasound scanning 2 to 30 days (mean, 10 +/- 6 days) after the procedure The duplex scanning documented occlusion of the GSV in 70 limbs (96%). In addition, DVT was found in 12 limbs (16%). None of these patients had pulmonary embolism . Early postoperative duplex scanning are essential, and should be mandatory in all patients undergoing RFA of the GSV.
47. Endovenous laser therapy and radiofrequency ablation of the great saphenous vein: analysis of early efficacy and complications. Puggioni A et al. J Vasc Surg. 2005 Sep;42(3):488-93 . Between June 1, 2001, and June 25, 2004, endovenous GSV ablation was performed on 130 limbs in 92 patients. RFA was the procedure of choice in 53 limbs over the first 24-month period of the study Routine postoperative duplex scanning was initiated at our institution only after recent publications reported thrombotic complications following RFA Thrombus protruded into the lumen of the CFV in three limbs (2.3%) after EVLT. One received a temporary inferior vena cava filter because of a floating thrombus in the CFV. No cases of pulmonary embolism occurred. …we recommend early duplex scanning in all patients after endovenous saphenous ablations.
48. Venous disorders: treatment with foam sclerotherapy. Bergan J at al DVT (1.8%) was limited to gastrocnemius veins (3 cases) and posterior tibial veins (3 veins). No pulmonary emboli or lung complications occurred. CONCLUSIONS: Treatment of a variety of venous disorders can be accomplished using foam sclerotherapy with results comparable to surgery and with an acceptably low rate of adverse events . These results, however, must be confirmed by larger experience in other institutions. This report describes initial experience in treating 332 patients
50. • Pre-operative evaluation is best performed by means of duplex scanning and physical examination. • Duplex scanning for venous insufficiency is simple and cost-effective. • Duplex mapping defines individual patient anatomy with considerable precision and provides valuable information that supplements the physician's clinical impression. Introduction
51. Pre surgical Duplex mapping The superiority of duplex ultrasound scanning over clinical examination for presurgical mapping has been well documented. Although ultrasound determinations of reflux at the junctions and at specific locations above and below the knee may be adequate for diagnosis and epidemiologic studies, pre-operative mapping must include the entire length of the saphenous veins. Such mapping may lead to selective surgical treatment and avoidance of complications related to extensive surgery.
52. Ultrasound mapping provides an opportunity for conservative ligation and perhaps sclerotherapy of tributary and perforating veins acting as the main source of reflux. Such procedures could be performed under ultrasound guidance in an outpatient setting. Pre-surgical Duplex mapping
53. Examination The examination consists of interrogating specific points of reflux with the patient standing. Forward flow is produced with muscular compression, and reverse flow is then assessed in the crucial areas that are important to operative planning. The patient is placed in an upright position so that the leg veins are maximally dilated.
54. Engelhorn CA; J Vasc Surg 2005 Pattern of great saphenous vein
55. Pattern of small saphenous vein Engelhorn CA; J Vasc Surg 2005
56. Prevalence of patterns of saphenous vein reflux Engelhorn CA; J Vasc Surg 2005
57. Goals of treatment Three principal goals must be kept in mind in planning treatment of varicose veins: The varicosities must be permanently removed and the underlying cause of venous hypertension treated. The repair must be done in as cosmetic a fashion as possible. Complications must be minimized.
58. Guidelines of Italian College of Phlebology The aim of varicose vein surgery is to relieve the symptoms, and prevent or treat any complications while recognising that the varicose disorder is likely to be progressive. “ Inadequate ” venous surgery is sometimes the main reason for post-surgical recurrences despite a good surgical technique. There are valid medical alternatives and sclerotherapy, for collateral veins, which therefore do not necessarily call for a surgical approach. Int Angiol 2003
59. Ablative surgery Complete and resolutive treatment Stripping Crossectomy Phlebectomy “Before any decision is taken on which technique is indicated, a detailed color flow duplex study should be done to avoid diagnostic errors”
60. Conservative surgery Sapheno-femoral external valvuloplasty CHIVA type 1 e 2 hemodynamic correction Crossectomy Duplex mapping is mandatory
61. Conservative surgery External valvuloplasty of the terminal and/or subterminal valve of the great saphenous vein, after thorough preoperative assessment, and with careful intraoperative checks, is a good way to treat saphenous reflux in 5-8% of patients. CHIVA 2 should not be used for saphenous veins with a caliber of more than 10 mm at the thigh, especially if the segment below the origin of the collaterals shows aplasia or hypoplasia, so as to limit the risk of saphenous thrombosis at the open cross. ICP Guidelines. Int Angiol 2003
62. Mini invasive treatment An increasingly popular alternative to traditional surgical stripping of the GSV for management of saphenous vein reflux is endovenous ablation (EVA) of that vein using laser energy, radiofrequency generated thermal energy or a chemical sclerosant. In all of these treatment the color flow duplex examination represents the basis and it is a “ part ” of method.
63. Endovascular obliteration Endovenous Laser - ELVT Radio frequency - VNUS Closure Foam ultrasound-guided sclerotherapy Before Laser After 1 week After 6 months
64. Endovenous Laser treatment Pre-operative, a Duplex scanning is performed in the upright standing position to map incompetent sources Of venous reflux and then to mark the skin overlying The incompetent portion of the GSV starting at the SFJ. After venous duplex mapping a percutaneous entry point is chosen. This point may be where reflux is no longer seen or where the GSV becomes too small to access (usually just above or below knee level).
65. Endovenous treatment Potential candidates for EVA include patients with reflux in an incompetent GSV or SSV or in a major tributary branch of the GSV or SSV such as the anterior thigh circumflex vein, posterior thigh circumflex vein, or anterior accessory GSV. Therefore, the presence of reflux in these veins is important to document using duplex ultrasound imaging , as pertaining to the CEAP A5 nonsaphenous category.
66. Endovenous treatment Variations to standard venous anatomy , when observed on the ultrasound examination , should be reported. These include tortuosity of the target vein, duplications, atresia, the presence of anatomic venous variants, or variable termination of the SSV. The diameter of the GSV and SSV, <= 2 cm of the junction with the deep vein (common femoral or popliteal) and target vein (if not the GSV or SSV) should be measured.
67. Endovascular methods Neither of endovascular obliterative procedures is validated as yet for long follow-up in the literature but these methods were proven to be less aggressive and effective at mid-term. They must therefore be considered as still in the clinical validation stage, and as such only used in accredited, qualified phlebology centers, after the necessary learning period. ICP Guidelines. Int Angiol 2003
68. What surgery ? Actually, there are not defined the hemodynamic specific patterns for each conservative surgical treatment. End point: Mini-invasivity Optimal long-term results Evolution of technique and methods
69. Recurrent varicose veins “ These are varicose veins that appear after surgical treatment, not the remains of the treated veins ” . The most frequent causes of recurrences are: Errors of diagnostic strategy and treatment Technical errors
70. Recurrent varicose veins “ Radical surgery", defined as physical extraction of the saphenous vein with all its collaterals and all the enlarged varices, which has been the surgical procedure of choice for varicose veins for almost a century, has been replaced by a " radical hemodynamic approach ", meaning elimination of the hemodynamic defects at the root of the formation of the varices (the reflux). Among the reasons leading to errors during surgery for varices in the legs, certainly the most important is the wide anatomical variety of the sapheno-femoral junction, and, moreover, of the sapheno-popliteal juncgtion, which can lead to the surgeon sometimes inadvertently leaving collaterals in place.
71. Recurrent varicose veins A "map" of the varicose veins and circulation defects of the lower limbs is used in CHIVA interventions and "traditional" surgical procedures. Incorrect application of these concepts, especially on an anatomical basis, can leave the way open to recurrences.
72. Conclusion After treatment, we have to control the patient by means of duplex ultrasound at 1st week, at 1st month and every sex months for 1 year. We have to know well the type of treatment for evaluating the results.
73. Conclusion The most important factor in determining a good treatment outcome is making an accurate diagnosis . Recognizing common clinical patterns of venous insufficiency is important, but with duplex US now readily available to many providers, direct visualization and mapping of venous pathways is possible. This will ensure not only complete treatment of all of the abnormal venous segments but preservation of normal veins .
74. Thank you for your attention !! In the evaluation of chronic venous insufficiency such as in the other reported conditions, the duplex examination have modified the therapeutical approach.