Venous Entry Approach

In the presence of leads exposed through tributary veins of the SVC system (cephalic, subclavian, external jugular), the venous entry approach is the first-choice technique (Fig. 4.22). This approach is also known as the superior or SVC approach, even if the term venous entry approach appears to be more correct. The venous entry approach consists of a combination of traction by a stylet, mechanical dilation of binding sites by the dilating sheaths, and countertraction at the tip of the lead by the outer telescopic sheaths. Lead extraction tools necessary to prepare the lead and accomplish the venous entry approach are reported in Table 4.6. 

Before starting the extraction procedure, the operator must identify the type and manufacturer of leads submitted to removal. One must identify lead fixation mechanism and type of fixation in case of an active fixation lead in some active fixation leads, special stylets are needed in order to unscrew the screw. After lead identification, the procedure of lead extraction consists of lead preparation and sheath application when gentle manual traction is unsuccessful. 

When performing extraction procedures, either proper lead preparation and lead control or correct use of sheaths by means of counterpressure and countertraction or progressive dissection and mechanical dislodgement is usually necessary. 

A crucial point is the powered dilatation along the SVC. First, appropriate lead control maintaining light and steady traction must be achieved. Second, the proper alignment between sheath and lead must be obtained and all pressure against the SVC avoided. Finally, it is important to orient the shorter end of the 15° bevelled sheath toward the SVC wall. Lasing is stopped before the tip is reached (about 1 cm 

Laser is activated and sheath ablates through binding site 

---

Venous entry approach, also known as the superior approach... 

It seems more accurate not to use the terms superior or inferior approach and, instead, to use the terms venous entry (implant vein) approach, transfemoral vein approach, and internal transjugular approach. In fact, the term superior approach can be misleading considering that either venous entry approach or internal transjugular approach can be considered superior approaches. 

Most operators begin with a venous entry approach using the implant vein and switch to a transfemoral approach if necessary [30]. Moreover, when leads are broken or free floating, the transfemoral approach is historically performed. Different venous approaches using the mechanical dilatation tech-... 

Fig 4 21 Approaches for transvenous lead extraction venous entry approach using the implant vein (a), transfemoral approach (b), internal transjugular approach (c)... 

Table 4,6 Lead extraction, venous-entry approach Tools...

How to Perform Internal Transjugular Approach if Venous Entry Approach Fails... 

Restarting a procedure described for the venous entry approach after introducer removal. A nor-... 

The internal transjugular approach was successful in 59 free-floating and 187 exposed leads as crossover from the venous entry approach. In two patients, due to failure to cannulate either the right or the left internal jugular vein, we used the right subclavian vein. Using this approach, 246 leads were completely removed. The procedure was partially successful in seven leads and unsuccessful in two. In the group with exposed leads, the approach increased the success rate from 90.3% to 98.3%. 

For the overall population treated at our center, 2,563 leads were completely (success rate 98.3%) and 23 partially (0.9%) removed, as shown in Table 5.3. We totally removed 2,202 of 2,254 pacing leads and 361 of 361 ICD leads. The venous entry approach was effective in 2,283 of 2,529 leads (90.3%). In the overall population, mean extraction time was 21 48 (range 1-360) min. 

Fig 5 16 Procedural outcome in lead extractions performed from January 1997 to December 2009. VEA, venous entry approach VES, venous entry site ISR, incremental success rate... 

The internal jugular venous approach is used as (1) a first choice in the presence of free-floating leads with attached tip (2) in case of an unsuccessful approach from the venous entry site. 

Unsuccessful Approach from Venous Entry Site... 

The venous-entry-site approach can be troublesome and risky in presence of (1) tight space between clavicle and first rib (as in medial access to the intrathoracic subclavian vein) (2) tenacious adher-ences in some critical points, such as at the innominate vein-SVC junction, SVC-right atrium spring, right atrium, tricuspid valve, and right ventricle. 

Free-floating leads Venous entry site approach impossible for unexposed intravasculai leads Binding-site dilatation with the transfemoral workstation is often ineffective particularly in the venti icle Tmnsjugular approach... 

Fig. 4.19 Deep (A) and superficial (B) anatomic relationships of the Magney approach to subclavian vena puncture. Point M indicates the medial end of the clavicle. X defines a point on the clavicle directly above the lateral edges of the clavicular/subclavius muscle (tendon complex). Rl. Point D overlies the center of the subclavian vein as it crosses the first rib. St, the center of the sternal angle Cp, coracoid process Ax, axillary vein star, costoclavicular ligament open circle with closed circle, costoclavicular ligament open circle with closed circle inside, costoclavicular ligament sm, subclavius muscle. The arrow points to Magney s ideal point for venous entry. (Magney JE, Staplin DH, Flynn DM, et al. A new approach to percutaneous subclavian venipuncture to avoid lead fracture or central venous catheter occlusion. Pacing Clin Electrophysiol 1993 16(11) 2133-2142, with permission.)...

Venous access can be carried out by either cutdown or the percutaneous approach. If the initial electrode has been placed via cutdown, the isolation of a second vein for venous access will prove extremely difficult. In this case, percutaneous approach should be attempted. Conversely, if the initial electrode has been placed percutaneously, then a second percutaneous approach or a cut-down is always possible. The second percutaneous puncture is usually carried out just lateral to the initial venous entry site. The initial lead can be used as a marker of the venous anatomy. If any difficulty is encountered, fluoroscopy is used to guide the lead using the chronic ventricular lead for reference (85,86). There is potential risk of damaging the initial electrode and care should be taken to avoid its direct puncture. The use of radiographic materials can also help define the venous structure as well as its patency. 

Extraction using the femoral vein is a much more versatile approach, hi reality, extraction via the femoral vein may be used as a primary approach and is the procedure of choice for extraction of broken or cut leads that are free-floating in the venous system, heart, or pulmonary artery. It is also the technique of choice in situations of grossly contaminated venous entry sites where there is risk of pushing contaminated debris into the central circulation by the superior approach. There are a variety of techniques for extracting leads by the femoral vein approach (Table 6.6). 

The axillary vein can be accessed lateral to the junction of the first rib and clavicle. The cephalic vein can be accessed by a "cut-down" approach in the delto-pectoral groove. Some physicians believe both of these avenues of venous entry may be less likely to fracture due to trauma between the first rib and clavicle. 

Another approach is the placement of a catheter in the subclavian vein via the femoral vein, which may be used to perform a radiographic contrast injection for outlining the venous structures, and may also be left as a target for subclavian needle entry. The catheter is advanced far laterally to the junction between the subclavian and axillary veins, and the use of this as a target allows for a very lateral entry and thereby avoids the problem of subclavian crush injury to the leads (41). The use of such a catheter for angiograms will also identify venous abnormalities, such as a persistent left superior vena cava prior to creation of the pacemaker pocket. 

---