Ask Dr. Z

I have a case that is giving me some trouble, and it comes up frequently. Following is the report.

INDICATION: The patient has a clotted AV graft that is used for dialysis. The patient is referred for thrombectomy.

CANNULATION OF THE AV SHUNT: An 18-gauge needle was used to cannulate the graft. A guidewire was placed under fluoroscopy. An angiographic catheter was inserted for venous access.

SVC VENOGRAM: A diagnostic angiographic catheter was inserted into the subclavian vein, to rule out a central lesion. The superior vena cava, brachiocephalic vein, and the subclavian veins were well visualized. The left subclavian vein was obstructed by the pacer wires.

PULL-BACK VEOGRAM OF AV SHUNT AND UNILATERAL EXTREMITY: The preferential draining vein was the basilic vein, which was of moderate caliber. Site and description of stenosis: The vein was collapsed at the elbow.

INTRO OF NEEDLE FOR ARTERIOGRAM/EMBOLECTOMY: An 18-gauge needle was used to cannulate the graft. A guidewire was placed under fluoroscopy. A 6-French sheath was used to cannulate the graft for arterial access.

THRMOBECTOMY OF AV SHUNT: Under fluoroscopy a Fogarty thrombectomy catheter was passed across the arterial anastomosis and using a sweeping motion, the clot was aspirated via the side port of the 6-French sheath. Number of sweeps: 4 Amount of clot aspirated: Large.

ANGIOPLASTY # 1:
Lesion location: basilic vein
Lesion length in cm: 1 cm
Balloon size: 7x6
Atmosphere inflation: 20
Time for angioplasty: 15 secsx7; <5secsx3
Results: Successful

ANTEGRADE ARTERIOGRAM: Under fluoroscopy, a guide wire passed across the arterial anastomosis. A 4 FR angiographic catheter was passed over the guidewire into the brachial artery in order to visualize enough of the native artery to be certain the graft had adequate arterial inflow, and to exclude stenosis of the arterial anastomosis and arterial inflow of the graft. 4 cms of the native artery were visualized. There was a stenosis at the arterial anastomosis.

ANGIOPLASTY # 2:
Lesion location: arterial anastomosis
Lesion length in cm: 1 cm
Balloon size: 6x6
Atmosphere inflation; 10
Time for angioplasty: 15 secsx5; <5secsx2

FOLLOW UP VENOGRAM OF THE AV GRAFT AND UNILATERAL EXTREMITY: The exit venogram showed blood flow determined using angiography was good. There was no residual stenosis.

RESULTS: Successful thrombectomy of the AV graft.