Khó khăn trong việc thúc đẩy ống thông qua guidewire. (A) ống thông hình thành một vòng lặp trong động mạch chủ. (B) đỉnh của ống thông flips trở lại vào động mạch chủ. (Trích từ Gerlock AJ, Mirfakhraee M. Khó khăn trong việc đặt ống thông nội bộ và bên ngoài động mạch cảnh trong | 456 Practical Handbook of Advanced Interventional Cardiology Figure 22-14 Difficulty in advancing the catheter over the guidewire. A The catheter forms a loop in the aorta. B The tip of the catheter flips back into the aorta. Adapted from Gerlock AJ Mirfakhraee M. Difficulty in catheterization of the internal and external carotid arteries. In Gerlock AJ Mirfa-khraee M eds. Essentials of Diagnostic and Interventional Angiographic Techniques. WB Saunders 1985. With permission from the publisher. Table 22-6 Mechanisms of failure in advancing the catheter 1. The wire is not strong enough to support the catheter. 2. The angle of the origin of the carotid artery is too acute. 3. Too much friction exists between the guidewire and the internal surface of the catheter. 4. The curve of the distal end of the catheter prevents further advancement. To solve the problem of a weak platform created by a floppy wire mechanism 1 the wire has to be advanced further so the stiff segment is in the proper area. If the wire is not strong enough it has to be exchanged to a stiffer To solve the problem of acute angle at the origin of the artery mechanism 2 a stiff wire will straighten out the angle and help to advance the wire. To solve the problem created by mechanism 3 due to excessive friction between the wire and the internal surface of the catheter the catheter should be advanced and the guidewire withdrawn Carotid Artery Interventions 457 Figure 22-15 Diagram showing how to reduce the friction between the wire and the internal surface of the catheter. A The catheter tip is at the orifice of the left CCA and the tip of the wire is in the left ICA. B The catheter is advanced while the wire is withdrawn. Adapted from Gerlock AJ Mirfakhraee M. Difficulty in catheterization of the internal and external carotid arteries. In Gerlock AJ Mirfakhraee M eds. Essentials of Diagnostic and Interventional Angiographic Techniques. WB Saunders 1985. With permission from the publisher. .
