Application of DEEPQUAKE Peripheral Lithotripsy System in a Case of Severely Calcified Arteriovenous Fistula Stenosis by Professor Liu Yangdong’s Team

Patient:54 years old, female.

Chief Complaint:"Admission due to a 20-year history of maintenance hemodialysis and decreased blood flow in the arteriovenous fistula."

History of Present Illness:The patient had undergone maintenance hemodialysis for 20 years due to chronic renal failure, with a radiocephalic arteriovenous fistula as the long-term dialysis access. Percutaneous transluminal angioplasty was performed 24 months and 7 months ago respectively due to fistula stenosis. Before this admission, the patient noticed weakened thrill of the fistula and insufficient blood flow during dialysis; ultrasound examination suggested multiple severe stenoses at the anastomosis site and outflow tract accompanied by serious circumferential calcification.

Past Medical History:Chronic renal insufficiency.

Physical Examination:The thrill at the radio-cephalic fistula site in the right forearm was weak on palpation, and auscultation revealed a low-pitched, short-duration bruit.

Preoperative Ultrasound:Multiple stenoses with severe calcification are shown, with the narrowest diameter at the anastomosis being 2.1 mm and the narrowest diameter of the outflow tract being 3.0 mm. The blood flow velocity at the anastomosis is 180 cm/s. (Figure 1)

Figure 1 Preoperative imaging shows severe calcification of the radial artery-cephalic vein arteriovenous fistula and venous outflow tract, with sluggish blood flow. Local valve stenosis is visible in the distal segment of the aneurysm, with calcified plaques attached to the surface.

Preliminary Diagnosis:Severe Calcific Stenosis of the Radial Artery-Cephalic Vein Arteriovenous Fistula.

Proposed Surgical Strategy:Intravascular Lithotripsy (Shockwave Balloon) + Post-Dilation with High-Pressure Balloon.

1. Puncture the right fistula vein and insert a 6F vascular sheath (Terumo). The super-selective guidewire passes through the stenotic segment, and angiography confirms the location and extent of the lesion (Figure 2). Angiography shows severe stenosis at the anastomosis and outflow tract, with significant local calcification, uneven contrast filling, and slow flow rate.

Figure 2: Severe stenosis at the anastomosis of the arteriovenous fistula, with uneven filling and slow flow of contrast agent in the local calcified area.

2. A 5mm×40mm high-pressure balloon (Zenflow, China) was introduced along a 0.035-inch guidewire for pre-dilation. Subsequent angiography showed insufficient lumen expansion (Figure 3).

Figure 3: After intraoperative pre-dilation with a balloon, there was no significant improvement in the local calcified lesion.

3. A 0.014-inch guidewire was used to introduce one.6mm×60mm Shock Wave Balloon (DEEPQUAKE, China)The calcified stenotic segments of the internal fistula vein and proximal arteriovenous aneurysm were dilated sequentially. After the balloon was pressurized to 4 atm, the shock wave system was first activated at level 3 energy (equivalent to an instantaneous 50 atm), applying two cycles (30 seconds per cycle) to each lesion segment. Subsequently, the energy was adjusted to level 5 (equivalent to an instantaneous 60 atm), and an additional 4-6 cycles were applied to each lesion segment (Figure 4).

Figure 4 Intravascular lithotripsy treatment process (a) and fluoroscopic observation (b). The figure shows the process of using a 6 mm×60 mm DEEPQUAKE shockwave balloon to dilate and fragment calcified lesions. During the procedure, the shockwave balloon generates a beam through electrode discharge (without actual thermal effect). Under fluoroscopy, the position of the intravascular lithotripsy balloon's radiopaque marker can be observed, and based on the marker’s location (as indicated by the arrow), the lesion area can be targeted while assessing the balloon’s shape to evaluate the degree of calcification fragmentation.

4. Follow-up angiography showed significant improvement in stenosis (Figure 5).

Figure 5 After treatment with the shock wave balloon, the calcified lesion in the anastomotic area decreased compared to before, and the stenotic lesion improved.

5. Post-dilation was performed using a 6mm×60mm high-pressure balloon, and the final angiography showed satisfactory lumen patency with smooth blood flow (Figure 6).

Figure 6: After post-dilation balloon treatment, blood flow velocity was satisfactory, and the calcified lesion showed significant improvement compared to before.

During the operation, the patient only felt mild pain, and no complications such as vascular rupture, dissection, or distal embolism occurred.

Three months after the surgery, ultrasound review showed that the calcified plaque at the anastomosis stenosis had significantly decreased compared to pre-operation, and the lumen had markedly improved. The inner diameter of the narrowest segment of the original anastomosis was 4.8 mm after dilation, and the inner diameter of the narrowest segment of the original outflow tract was 5.2 mm (Figure 7). The blood flow velocity at the anastomosis increased from 180 cm/s pre-operation to 420 cm/s.

Figure 7: A 3-month postoperative follow-up showed significant improvement in multiple calcified lesions compared to pre-operation, with the disappearance of calcified plaques within the local lumen and marked improvement in lumen condition.

• Offering an 80mm length balloon, more suitable for long lesions,Reducing operation time and IVL treatment frequency, cost-effective