1. Acute Ischemia Of Lower Limb (AILL)
Aetiology
1. Embolisation most common cause
heart as a source - 70 %,
Atrial Fibrillation,
AMI with mural thrombus
2. Acute thrombosis superimposed upon
stenosis
3. Popliteal Aneurysm
Dr. Rajdeep Agrawal

2. Acute Ischemia Of Lower Limb
The extent of ischemia & final outcome depends upon
1. Size & location of clot
2. Extent of collateral circulation
3. Time between onset of occlusion & treatment
Dr. Rajdeep Agrawal

3. Clinical Features Characterized by 5 “P”s 2. Pallor- waxy
1. Pain - sudden onset
2. Pallor- waxy
3. Parasthesia – numbness
4. Pulselessness
5. Paralysis
Dr. Rajdeep Agrawal

4. Therapeutic Strategies in Acute Ischemia
Most common vascular emergency
1. Intra arterial thrombolysis
2. Thrombo-aspiration with catheter
3. Mechanical thrombolysis
4. Surgical embolectomy – Fogarty
catheter
Dr. Rajdeep Agrawal

5. Peripheral Intra-arterial Thrombolysis (PIAT)
Rapidly restores blood flow to ischemic limb & identifies underlying lesions for percutaneous or surgical intervention
Catheter directed local delivery of thrombolytic agents directly at the site of thrombosis is significantly more effective than systemic thrombolysis & is associated with lower bleeding complications
Dr. Rajdeep Agrawal

6. Thrombolytic Agents Streptokinase Urokinase
Recombinant human tissue type plasminogen activator (rtpA, alteplase)
In recent years UK & rtpA have largely superceded & replaced SK as preferred agent
Dr. Rajdeep Agrawal

7. Peripheral Intra-arterial Thrombolysis (PIAT)
PIAT – Common procedure
Angiography is done
Thrombus is located
Multiple end hole catheter is advanced to the upper limit of the thrombus
One of the infusion methods shown next is then used
Dr. Rajdeep Agrawal

8. PIAT– Infusion Methods
Stepwise infusion
Done by stepwise advancement of infusion
catheter as thrombus dissolves
Graded infusion ( McNamara’s protocol)
gradual tapering of infusion rate
Continuous infusion
Pulse spray technique
Dr. Rajdeep Agrawal

9. PIAT--McNamara’s Protocol
UK units/min x 2hrs
2000 units/min x next 2hrs
1000 units/min x next 4-24 hrs or
until the lysis is completed
Systemic heparin continued during PIAT And till definite endovascular or surgical Rx of underlying lesion is done
Dr. Rajdeep Agrawal

10. PIAT--McNamara’s Protocol
Complete lysis is considered if > 75%
of the clot dissolves
Initial reestablishment of flow
takes on an 3.3 hrs avg.
complete clot lysis up to 13hrs avg
Systemic Heparin is continued through this period
Dr. Rajdeep Agrawal

11. Predictors Of Successful Thrombolysis
Easy traversability of clot with non-hydrophilic guide wire 0.035”
Significant lysis within 2hrs
Dr. Rajdeep Agrawal

12. Thrombolysis-Contraindications
Absolute
1. Recent Cerebro Vascular Accident,
neurosurgery, intracranial trauma,
within the last 3 months
2. Active bleeding diathesis
3. Recent GI bleed (< 10days)
4. Irreversible ischemia
Dr. Rajdeep Agrawal

13. Thrombolysis-Contraindications
Relative
1. Cardiopulmonary resuscitation,
major nonvascular surgery, trauma
within last 10 days
2. Uncontrolled HT systolic > 180
diastolic > Puncture of non compressible vessel
4. Intracranial tumor, diabetic proliferative
retinopathy, bacterial endocarditis,
pregnancy
Dr. Rajdeep Agrawal

14. PIAT -- Complications Significant hemorrhage 1% Distal Embolisation
Dr. Rajdeep Agrawal

15. Post PIAT Management
Underlying flow limiting lesion is present in more than 70% cases & surgery or PTA can be performed immediately after thrombolysis with no additional risk of hemorrhage
No underlying lesion -- anticoagulation
Dr. Rajdeep Agrawal

16. Treatment of Acute Occlusion
Embolectomy - Using Fogarty’s catheter -> Catheter passed beyond emblous, balloon inflated & pulled back till blood comes
Direct Embolectomy - Artery exposed, transverse incision, clot removed.
Intra-arterial Thrombolysis - TPA preferred. Arteriography done and a catheter embedded in clot - Thrombolytic agent infused over several hrs
Dr. Rajdeep Agrawal

17. Surgical Embolectomy Problems Relatively simple procedure
Done under LA, small incision in the groin, using Fogarty’s cath.
Problems
1. Blind procedure, can be traumatic
2. Not successful in 10 – 30% cases
3. Inefficient in multistenosed artery
4. Complete removal of thrombus difficult in leg arteries
Dr. Rajdeep Agrawal

18. Post PTA MX Antiplatelet agents LMW Heparin X 7 – 10 D
IV / oral Trental
Statins
Aggressive control of risk factors
Dr. Rajdeep Agrawal

19. Newer Techniques Of Angioplasty
Atherectomy
Directional
Percutaneous Rotational
TEC
LASER
Stent
Dr. Rajdeep Agrawal

20. Directional Atherectomy
It excises the atheromatous plaque material into very fine slices which can be retrieved outside body
Dr. Rajdeep Agrawal

21. Percutaneous Rotational Atherectomy (Rotablator)
Dr. Rajdeep Agrawal

22. LASER
A LASER produces an intense beam of light in uniform wavelength that can be precisely focused to deliver high energy levels to a small area
It converts solid plaque to gas which is soluble in blood
Dr. Rajdeep Agrawal

23. Stent
An expandable metallic helical device which is permanently implanted in the artery.
Mechanism
The prosthesis acts as a scaffold to hold the artery open
Prevents recoil of the vessel
Reduces Restenosis
Dr. Rajdeep Agrawal

24. Lower Limb Ischemia - Approach to therapy
Risk factor management
* Abstinence from smoking
* Control of diabetes
* Control of hyperlipidemia
Dr. Rajdeep Agrawal

25. Lower Limb Ischemia - Approach to therapy
Risk factor management
* Weight reduction
Control of hypertension, CHF, CRF
Chronic anticoagulation oral with judicious use of PT PI measurements
Dr. Rajdeep Agrawal

26. Lower Limb Ischemia - Role of Drugs
Pentoxyfylline – not useful
Antiplatelet Agents
Prostaglandins
Vasodilators
Dr. Rajdeep Agrawal