Ống thông được bố trí trên một đường thẳng, để giảm thiểu ma sát với các ** Balloon nong mạch của các mạch lớn: hiện tại kích thước bóng tối đa là 4 mm đường kính, do đó, khi động mạch vành hoặc SVG lớn hơn 4 mm , kỹ thuật bóng ôm hoặc sử dụng một khí cầu ngoại vi | 116 Practical Handbook of Advanced Interventional Cardiology and the catheter should be well flushed before starting the procedure. The catheter should be positioned on a straight line to minimize any friction with the Balloon angioplasty of large vessels Current maximal balloon size is 4 mm in diameter so when the coronary artery or the SVG is larger than 4 mm the hugging balloon technique or use of a peripheral balloon is suggested. The two balloons are positioned side by side and inflated simultaneously. The combined diameter will be 70 of the sum of each balloon alone and the cross-section area will be oval rather than 6 TROUBLE-SHOOTING TIPS How to cross a lesion The standard maneuver is to advance a balloon with the left hand while pulling the wire taut with the right hand or with the help of an assistant . This technique is to decrease the friction between the wire and the lumen of the balloon catheter. It also helps to keep the wire straight and taut so the balloon catheter can slide more easily on it. Failure to cross a lesion The causes of failure to advance a balloon across a tortuous segment in order to reach a lesion are multiple. If the lesion is too severe the balloon tip will not cross and the guide will back out then the guide should be held steady engaged deeper or be replaced. If there is excessive tortuosity of the arterial segment proximal to the lesion the solutions are 1 to secure a more stable position of the guide or 2 to use a stiffer wire for the balloon to be tracked on or 3 to straighten the artery by asking the patient to take a deep breath or 4 using a buddy wire placed adjacent to the primary wire. A wiggle wire is useful at deflecting the tip of the balloon of plaques and stent struts better allowing lesions to be crossed. A smaller balloon with a lower profile or length may also succeed in crossing a tight lesion. Once inflated it creates a channel sufficient for the optimal size balloon to enter. The different .
