Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_3590_Библиотеки_им_академика_М_И_Перельмана

Transseptal access is discussed in a previous chapter; however, it can be obtained in a variety of methods. Importantly, the use of ICE and TEE has allowed for crossing the septum in a specific location. As the PVs are quite posterior in the LA, an anterior transseptal puncture can be useful to approach both the left- and right-sided veins. For transseptal access, typically either an 8F transseptal sheath (St. Jude, SL1) is used to cross to the LA or an Agilis sheath, and wire position is established in the LA with an Amplatz stiff or Inoue wire placed through the sheath that was used to initially cross the septum. Once in the LA, heparin should be administered as needed to maintain an activated clotting time (ACT) between 250 and 350 seconds, generally at a dose of 200 units per kilogram. At this point, with the wire position firmly established in the LA, a steer­able sheath such as an Agilis or, alternatively, Dexterity sheath can be introduced into the LA for more precise movement and positioning. In patients with a thickened fibrotic septum, if there are problems associated with needle entry into the LA, a Safe-Sept wire or radiofrequency delivered to the needle may be of value. Should the steerable sheath not readily cross the septum, dilation with either the Inoue dilator or even a coronary or peripheral set of wire/balloon can be used to readily gain access to the LA with the larger, steerable sheath. Certainly, a larger guiding catheter such as a 6F to 8F multipurpose catheter can be used to directly access and engage the affected PV. A conventional coronary guiding catheter is usually used in the event that intravascular ul­trasound (IVUS) is needed to assess the lesion more carefully. Without the steerable sheath, however, this creates some difficulty in terms of support as well as maintaining access to the LA while switching out equipment. Either along or through the steerable sheath, we commonly use a 6F multipurpose catheter to intubate the affected PV, using clockwise maneuvering for posterior positioning and counterclockwise movements to position the sheath more anteriorly. Engagement with the orifice of the affected PV can be confirmed by brief contrast injection on fluoroscopic angiography or with ICE guidance using the venous jet.