Limited thoracotomy

Successful placement of the LV lead in the target vein has been aided by continuing improvements in the available delivery tools as well as individual operator experience. In CONTAK CD (performed from 1998 to 2000), 79% of attempted implants resulted in successful transvenous implant of the LV lead. In COMPANION (2000 to 2002), the success rate was 89%, with median procedure duration of 2.8 hours. And in CARE-HF (2001-2003), the success rate was 95% (86% on first attempt). Patients who fail to undergo successful transvenous implantation of the LV lead into an optimal target vein have the option to undergo limited thoracotomy for direct implantation of an epicardial LV lead. 

Initially, almost all pacemaker and ICD procedures were approached exclusively from the epicardial point of view. But with the development of a transvenous approach, either by cutdown or percutaneous techniques, now almost aU pacemaker and ICD procedures are approached on a transvenous or nonthoracotomy basis. Today, the epicardial approach is reserved for certain unique circumstances. Electrodes can be placed on the epicardium by a variety of techniques. This involves a subxiphoid incision, and limited thoracotomy, or direct application of electrodes on an exposed heart. Recently, mediastinoscopy and thoracoscopy have been used to apply permanent pacing and rate-sensing electrodes as well as patch electrodes. The transvenous approach can be performed by venous cutdown, percutaneous venous access, or a combination of the two. 

There are three fundamental anatomic approaches for lead extraction (23,24,37). The first is retrieval by the implant vein, frequently called the superior approach. This approach can include simple traction. Buck s traction, the use of locking stylets with traction, or the use of locking stylets with countertraction sheaths. The second approach is transfemoial, frequently called the inferior approach. This approach may involve several distinct techniques. When this involves entangling a lead with a pigtail catheter, the catheter is passed from below. When free open ends present themselves, a wire-loop system may be used with traction. Both the Dotter retriever and Dormia basket may also be applied for traction from below. Finally, the lead to be removed may be extracted by the Byrd Femoral Work Station with the use of a combination of snares and wire loops. The third and final approach is retrieval of leads by a limited thoracotomy. 

A limited thoracotomy should be considered if both the superior (implant vein) and inferior (femoral) approaches fail to extract the lead. In 1985, Byrd and associates described a limited surgical approach for extracting chronic pacing leads that were unsuccessfully removed by transvenous techniques (46). A limited thoracotomy with low morbidity has been developed that totally avoids an extensive thoracotomy, as well as median sternotomy. This approach generally has been used as a primary approach in patients with uninfected lead systems that require removal. The transatrial approach allows for removal of leads that are inaccessible by the superior vena cava or inferior vena cava approach. This approach also affords ease of replacement of endocardial lead systems by the same technique. This is why it is most amenable to patients who are not infected. The transatrial approach with a limited thoracotomy has also been used for replacement of endocardial lead systems when all available veins have been obliterated after a superior vena caval or inferior vena caval extraction procedure. 

Fig. 6.37 The transatrial approach with limited thoracotomy. An atriotomy incision is made. For an atrial lead, the entire lead is removed retrograde. The ventricular lead is pulled up through the atriotomy with forceps. The lead is grasped and transected. The proximal end is then removed retrograde. A locking stylet is inserted into the remaining distal portion of the lead, which is then removed using the countertraction technique. (From Byrd CL, Schwartz SJ, Sivina M, et al. Technique for the surgical extraction of permanent pacing leads and electrodes. J Thorac Cardiovasc Surg 1985 89(1) 142-144, with permission.)...

One major drawback with surgical cell delivery is the invasiveness of the delivery process. The need for thoracotomy or sternotomy limits the potential patient population—in that patients with greatly reduced LV function will not easily tolerate this procedure. 

The surgical instruments for endocardial lead extraction are identical to those for a permanent pacemaker procedure, which merely requires a minor surgical tray with a limited number of instruments. A standard thoracotomy tray should be readily available in addition to a minor surgical set. A pneumatic thoracotomy saw and/or sternotomy saw should be available in the operating room and even in the catheterization laboratory, in case a thoracotomy or sternotomy is required. Unlike the permanent pacemaker procedure, lead extraction should have a source of reliable suction readily available. 

One of the most significant factors related to the importance of addressing this post-operative condition is the observation that the number of surgical procedures that are at risk has increased markedly over the decade. Subsequently, if we do not address the pathways and treatments of these chronic pains, the prevalence will probably increase. In turn, the physical, social and economic burden will also increase. In one study with post-thoracotomy patients, persistent post-operative pain limited normal daily activities in more than 50% of these patients and sleep disturbances were reported in 25-30% of this population. These disruptions are often driven by inadequate pain control. 

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