Vascular Intervention (MC)

• Vascular surgery interventions address Peripheral Artery Disease (PAD).

Approaching PAD

• PAD is approached by considering the indication, utilizing imaging, and then performing interventions.

Angiogram

• An angiogram is a common, invasive procedure.
• It provides anatomical details of a patient's arteries.
• Angiograms are used for planning open revascularization
• They can be converted into a therapeutic procedure to revascularize a leg.

Endovascular Surgery

• Endovascular surgery is performed with angiography.
• Procedures are used inside the artery to force open occluded or stenotic arteries.
• Endovascular revascularization surgery options include:
  • Balloon angioplasty with or without antirestenosis drug
  • Stent placement with or without antirestenosis drug
  • Atherectomy using a plaque removal device
• Endovascular surgery usually involves a small puncture over the common femoral artery.

Angiogram: Considerations

• Angiograms can be performed with local anesthesia and sedation.
• It requires patients to tolerate lying on their back.
• Contraindications for angiograms:
  • Acute kidney injury or chronic kidney disease near dialysis due to the risk of permanent renal failure
  • Untreatable contrast allergy
  • Uncontrolled coagulopathy, indicated by an INR greater than 1.5-2

Angiogram: Equipment

• Angiogram equipment includes:
  • Fluoroscopy table
  • C-arm or fixed imaging system
  • Lead aprons, thyroid shields, barriers for radiation protection
  • Puncture needle, access wire and sheath for vascular access
  • Wires and catheters for navigation and intervention
  • Contrast and heparinized saline for visualization and preventing clotting
  • Balloons and sheaths as needed for angioplasty and delivery
  • Intravenous heparin to prevent thrombus formation

Angioplasty vs. Stent

• Endovascular therapy works best with short segment treatment of large arteries.
• Iliac arteries have a high likelihood of sustained benefit from endovascular therapy.
• Femoropopliteal arteries have a good chance of sustained benefit.
• Tibial arteries have low rates of long-term patency, but short-term therapy can provide enough blood flow to heal a wound.
• Stents provide incremental improvement over balloon angioplasty for longer lesions in the iliac, femoral, or popliteal arteries.
• Stents have no proven benefit below the knee.

Angiogram: Postoperative

• After an angiogram, the sheath is removed and the puncture site is closed.
• Closure is achieved through either direct compression or a special closure device.
• Patients need to remain on bed rest for 4-6 hours.
• The puncture site should be monitored for hematoma or pseudoaneurysm.
• If the puncture site is clean after 4-6 hours, the patient can ambulate and may be discharged home.

Open Surgery

• Open surgery for PAD involves two main techniques:
  • Endarterectomy: Plaque is removed from an artery
  • Bypass surgery: A substitute vessel creates a new path around an occluded artery
• Procedure names indicate the location of the surgery, for example:
  • Common femoral endarterectomy
  • Aorto-femoral bypass
  • Femoral-popliteal bypass

Graft Material

• For infrainguinal bypass surgery, a single segment vein conduit yields the best results.
• Suitable vein conduits include the great saphenous vein or cephalic/basilic veins from the arms.
• Prosthetic bypass grafts (PTFE, Dacron) work well above the inguinal ligament.
• They have inferior results when used below the inguinal ligament.

Importance of Inflow

• Occlusion of the aorta, iliac, and/or common femoral arteries reduces blood flow to the entire leg.
• The entire leg becomes dependent on collateral circulation when major arteries are occluded.
• Restoring inflow provides the most benefit in such cases.

###PAD Risk Factors

• Risk factors such as age, gender, diabetes mellitus, hypertension, hypercholesterolemia and smoking contributes different arterial occlusion patterns.

Case: Femoral Endarterectomy

• A 67-year-old man with hypertension presented with left foot ischemic rest pain and an ulcer between the left 3rd and 4th toes.
• The exam revealed an absent left femoral pulse.
• A computed tomographic angiogram (CTA) showed extensive left femoral plaque.
• Post-surgery, a palpable PT pulse was achieved.
• The patient recovered well, the ulcer healed and ischemic rest pain disappeared.

Surgeon's Saying

• In cases of Chronic Limb-Threatening Ischemia (CLTI), the goal is to return a palpable pulse to the foot.

Case: Chronic Limb Threatening Ischemia

• A 60-year-old man with diabetes and a history of active smoking presented with a left non-healing hallux wound.
• Palpable femoral pulses were present.
• The patient was taken to the operating room for an angiogram.
• There was a 20+ cm occlusion of the left Superficial Femoral Artery (SFA) along with occlusion of the tibioperoneal trunk.
• An incision was made on the medial leg from the groin to the upper calf.
• The great saphenous vein was harvested from the left leg and found suitable for bypass.
• The vein was sewn in non-reversed configuration to the common femoral artery and then to the posterior tibial artery.
• Vein valves were cut with a Mills valvulotome to allow proper flow.
• A completion angiogram was performed.

Postoperative CLTI

• A palpable left PT pulse at the ankle was achieved postoperatively.
• Wound healing requires 3 critical components:
  • Wound care/offloading
  • Treatment of ischemia
  • Treatment of infection
• Ultimately, the patient’s hallux wound healed.

Case: Ischemic Rest Pain

• A 71-year-old woman with hypertension, coronary artery disease, and diabetes.
• She had a history of intermittent claudication progressed to ischemic rest pain over several months.
• Palpable femoral pulses were present.
• A 20 cm long segment of the left SFA was occluded, and there was a significant stenosis of the tibioperoneal trunk.
• The posterior tibial artery was patent to the foot, but the peroneal artery occluded in the distal calf.
• The anterior tibial and dorsalis pedis arteries were chronically occluded.
• The patient underwent balloon angioplasty and stenting of the SFA.
• The popliteal and tibioperoneal trunk underwent balloon angioplasty.
• The patient had a palpable left PT pulse at the ankle.
• Intermittent claudication and rest pain were resolved.

Conclusions for Vascular Interventions

• The goal of any revascularization is to provide sufficient foot perfusion to heal wounds.
• Open and endovascular approaches each have advantages and disadvantages.
• The choice of procedure must be tailored to the patient's situation.
• Lower extremity bypass with a saphenous vein is the best revascularization procedure.
• This is if the patient is healthy enough, has at least a 2-year life expectancy, and has a suitable vein.