Related Experiment Videos
Hemolytic effect of the Amplatz thrombectomy device
G K Nazarian1, Z Qian, C C Coleman
1Department of Radiology, University of Minnesota Hospital and Clinic, Minneapolis 55455-0392.
Insights
The Amplatz thrombectomy device (ATD) causes temporary hemolysis, indicated by decreased haptoglobin and increased free hemoglobin. Caution is advised for certain patient groups and with prolonged activation times.
Area of Science:
- Vascular Surgery
- Hematology
- Medical Device Evaluation
Background:
- Mechanical thrombectomy is increasingly used for vascular occlusions.
- The Amplatz thrombectomy device (ATD) is a tool for removing blood clots.
- Evaluating device-induced complications like hemolysis is crucial for patient safety.
Purpose of the Study:
- To assess the hemolytic effect of the Amplatz thrombectomy device (ATD).
- To compare hemolysis in animal models versus human patients undergoing thrombectomy.
Main Methods:
- The ATD was activated in canine abdominal aorta, inferior vena cava, or femoral artery (1-2 min).
- The ATD was used in human patients for various vascular occlusions (1-4 min).
- Laboratory tests (haptoglobin, plasma free hemoglobin, hemoglobinuria) monitored for hemolysis.
Main Results:
- All dogs showed decreased haptoglobin, increased plasma free hemoglobin, and hemoglobinuria.
- Eight of nine patients exhibited decreased haptoglobin and increased plasma free hemoglobin; one had hemoglobinuria.
- Hemolysis was more pronounced in animal subjects compared to human patients.
Conclusions:
- The ATD demonstrates a clear, transient hemolytic effect.
- Use in children is not recommended; caution is advised for anemic, hypoxemic, or renally compromised patients.
- Close monitoring of activation time is essential, as hemolysis appears dose-dependent.
Purpose:
The hemolytic effect of the Amplatz thrombectomy device (ATD) was evaluated in nine dogs and in nine patients.
Materials And Methods:
The device was activated for 1-2 minutes in the abdominal aorta, inferior vena cava, or femoral artery of nine dogs. The device was activated for 1-4 minutes in the nine patients in occluded lower extremity bypass grafts (n = 5), native superficial femoral artery (n = 1), a pulmonary artery embolus (n = 1), a portocaval shunt (n = 1), and an iliac vein stent (n = 1). Patients were examined for laboratory evidence of hemolysis following mechanical thrombectomy.
Results:
In all dogs haptoglobin level decreased, free hemoglobin level in the plasma increased, and hemoglobinuria was present. There was no change in renal function. The level of haptoglobin decreased and the level of plasma free hemoglobin increased in eight patients, with hemoglobinuria detected in one. More hemolysis was observed in the animals than in the patients.
Conclusion:
The ATD has a definite transient hemolytic effect. Until further studied, it should not be used in children and should be used with caution in patients who are anemic, hypoxemic, or have potentially reversible renal insufficiency. Activation time should be monitored closely because hemolysis probably increases with increasing activation time.