Endovascular Treatment for Acute Limb Ischemia

M Mazen Hachem*, MD, PhD, FACS., M Bosaeed* and M Wakka* Gh. Atasi**, A. Qanawi**, M Brembali**,

*Division of Vascular Surgery**Division of Interventional Radiology

King Abdul-Aziz Medical CityJeddah, KSA

Introduction

• Acute Limb Ischemia is a catastrophic event– Threatens both the patient's limb and life.

• Traditionally, Surgery has been the “gold standard”– However, the multiplicity and complexity of medical co

morbidities • Account for high rates of perioperative morbidity and mortality.

• Blaisdell’s landmark study (1978)– Death in 30% of patients, amputation in 25% of

survivors

Introduction

• These results have prompted interest in a less invasive treatment strategy for ALI.

• In recent years, Catheter-Directed Thrombolysis Therapy (CDT) became the treatment of choice for many patients in acute limb ischemia.

Thrombolysis in the Management of Lower Limb Peripheral Arterial Occlusion—A Consensus DocumentJ Vasc Interv Radiol 2003; 7:S337–S349

Aim

• To assess the efficacy & safty of CDT in patients with ALI and semi ALI– Initial success rate–M & M rates of CDT will be discussed.

Methods: Patients

• Inclusion Criteria– Category I, IIa, IIb

• Clinical Category of SVS/ ISCSV– Catheter penetrate the thrombotic or embolic occlusion

• Exclusion criteria – Limb-threatening ischemia requiring immediate surgery– Non penetrable occlusion– Contraindication of thrombolysis

Clinical Categories of ALI SVS/ ISCVSII

II. Viable

II. Threatened a. Marginally

b. Immediately

III . Irreversible

Not immediately threatened

Salvageable ifpromptly treated

Salvageable with immediate revascularization

Major tissue loss or permanent nerve damage inevitable

None

Minimal (toes) or none

More than toes; associated with rest pain

Profound, anesthetic

None

None

Mild to moderate

Profound paralysis (rigor)

Audible

(Often) inaudible

(Usually) inaudible

Inaudible

Audible

Audible

Audible

Inaudible

CategoryDescription or

PrognosisSensory

LossMuscle

Weakness

ArterialDoppler Signals

VenousDoppler Signals

Rutherford et al. J Vasc Surg. 1997;26:517–538.

Methods: Protocol & Procedure• rtPA was administrated through a coaxial catheter,

multi-holes impeded in the thrombus• 5X5X5 mg in 15min interval as bolus (pulse spray

technique)• Control angio. 1/h + readjustment of cath. • 0.5-2mg rtPA/ h by infusion pump.• Heparin 500-1000U/h through vascular sheath

side port. (APTT ratio 1.5-2).• ICU setting

Methods: Protocol & Procedure

• Clinical/Angiographic evaluation• CDT termination–Worsening or no clinical improvement in 2h– Complications required its cessation– Adequate vessel patency was achieved

Methods: Protocol & Procedure

• Success was defined as:– Clot lysis sufficient to restore anterograde flow

throughout the previously occluded segment.– Clinical improvement even with moderate

angiographic success• Complementary PTA when indicated.

Results: Patient Characteristics• Thirty tow patients – M/ F ratio: 1.7– Median age 64 years– 78% were diabetics. – 33 limb (7 upper limbs, 26 lower limb)

• 30 limbs (82%) were classified as category I, IIa• 3 limbs (9%) were IIb • 3 limbs (9%) were IIIa–Underwent CDT at our institution from

December 2003 to June 2008.

Results: Patient Characteristics• The underlying causes of ALI– 48.5% arterial thrombosis– 35.5% arterial embolism– 18% graft occlusion

• Ischemia duration – 70% < 14 days

Results: Patient Characteristics• The arterial sectors involved – Femoral in 12 cases– Popliteal in 4 cases– Aortoiliac in 1 case– Distal in three cases– Subclavian in 5 cases and brachial in tow– Aorto-bi-femoral bypass in one.– Fem-Distal PTFE bypass in 2– Fem-Distal venous bypass in 2

Results• All had CDT, some followed by PTA.–Except• 7 /11 embolectomy with distal

peroperative CDT • 2 redo bypasses (PTFE) with distal

peroperative CDT

Results• rtPA dose range 30 to 100mg• Mean duration 18h (range: 12 to 60h)

Results: Outcome• 91% limb salvage.– 10% had recurrence in one month

• 6% major limb amputations – One below knee– One below elbow

• 3% hospital mortality • 12.5% had bleeding around the catheter – In tow patients CDT were stopped

• Saved limbs

Discussion• Even our patients are: –Heterogeneous, encompassing occlusion

of grafts and native arteries–Thrombotic and of embolic origins–Upper and lower extremities–< > 14 days of limb ischemia–78% diabetics

Discussion• CDT induced recanalization in 91%

–Within a mean of 18 hours (range,12 to 60 hours). – The rtPA protocol followed was as recommended

by Eu. Consensus 2003.– The last 12 patients 0.5 mg rtPA/h was used• No difference was found between high and low dose.

– Duration– Bleeding

Insignificant Variables Significant Variables

Predictors of Success: CDT

• Duration of occlusion• Location• Thrombosis/

embolism• Motor loss• Age/sex• Diabetes status

• Wire passage• Catheter in clot• Conduit material• No.: Segment

involved

Ouriel et al. Radiology. 1994;193:561–566.

Variable

Ouriel et al. Radiology. 1994;193:561–566.

Statistically Significant Predictors of Successas Determined by Multivariate Analysis

Odds Ratio (95% CI) P ValueMedical history of diabetesProcedure

Catheter into thrombusGuide wire traversal of thrombus

Segments involved*OneTwo

Conduit typeNative arteryProsthetic grafts

0.75 (0.40—0.89) .044

7.40 (2.11—16.90) .001

3.10 (1.72—8.52) .003

1.60 (1.47—1.79) .0151.42 (1.29—1.77) .029

1.25 (1.05—1.42) .0411.51 (1.11—1.92) .017

*Grafts were counted as one segment.

Guide wire traversal

Guidewire

Embolic Occlusion

Initial Angio Thrombolysis Final Result

Popliteal Thrombosis

CDT & PTA

Initial Angio Thrombolysis PTA Final Result

Axillary Embolic Occlusion

Comparing Surgery and Lysis: What Data Exist?

1. The Rochester Trial:1994, 114 patients, UK vs Operation

2. The STILE Trial:1994, 393 patients, rt-PA vs UK vs Operation

3. The TOPAS Trial:Phase I: 1996, 213 patients, r-UK dose rangePhase II: 1998, 544 patients, r-UK vs Operation

The Rochester Trial1-Year Data

Amputatin Mortality0%

5%

10%

15%

20%

25%

30%

35%

40%

45%

0.18 0.160.18

0.42

UKOperation

Inci

denc

e of

Clin

ical

Eve

nts (

%)

The STILE Trial: 1-Month Data

Death Amputation Major Morbidity

0%

5%

10%

15%

20%

25%

4% 5%

21%

5% 6%

16%

ThrombolysisSurgery

Inci

denc

e of

Clin

ical

Eve

nts (

%)

The STILE Trial. Ann of Surg. 1994;3:251–268.

The STILE Trial: Post-Hoc AnalysisAmputation 1 Month

< 14 days > 14 days0%

2%

4%

6%

8%

10%

12%

14%

16%

18%

0.06 0.05

0.18

0.02

ThrombolysisSurgery

The STILE Trial. Ann of Surg. 1994;3:251–268.

Heparin + CDT• Therapeutic heparinization with

thrombolysis has been controversial:–Most clinicians used systemic heparinization

500 U/hr) in conjunction with thrombolysis.

Blaisdell’s landmark study (1978

Discussion

• Our data showed– No amputation in category IIb– Long ischemic duration in IIa resulted in limb

salvage.– Severe bleeding in 2 patients could not be

attributed to heparin 500U/h, PTT ratio: 1.5– Our death was not related to CDT• Saved limb

–M & M were from IIIa

Conclusion• CDT has been shown to be safe and useful for

rapid release of ischemic symptoms by clot dissolution / Complete or partial

• CDT has low rates of morbidity and mortality. • CDT unmasking underlying stenoses,– Helping to determine the best treatment strategy in

elective basis • PTA• Surgery.