ABC | Volume 111, Nº5, November 2018

Original Article Albertini et al The role of preoperative venography in reoperations Arq Bras Cardiol. 2018; 111(5):686-696 In all the cases studied, surgical planning was based on the findings of preoperative venography. Of the 53 patients without significant lesions, there were 28 cases in which we decided to implant new leads without removing the old ones, while in 22 cases the implantation of new leads was combined with removal of old ones in order to avoid overpopulation. There was complete removal of the system in other 3 cases. On the other hand, of the 23 cases where moderate stenosis had been diagnosed, there were 14 in which there was the implantation of new leads combined with the removal of old ones; only in 9 cases our decision was to implant new leads and maintain the old ones. In the 24 cases where new leads did not require any removal and severe stenosis or venous occlusion had been diagnosed, the findings in the venography showed that in 13 cases the internal jugular vein and the ipsilateral brachiocephalic trunk of the implant were free from any obstructions. Of those, only in 2, because the patients were young, a transvenous extraction procedure was planned to avoid overpopulation of leads. Of the 11 cases where no extraction was performed, there were 5 in which the internal jugular vein was used as access. In the other 5 cases, it was possible to go beyond the lesion in the subclavian vein with the aid of 0,14” hydrophilic wire guides. Of the 8 cases where the internal jugular veins could not be used as access because there was obstruction in the ipsilateral venous brachiocephalic trunk, in only one case the medical team chose to conduct a new contralateral implantation. In the remainder (7), transvenous extraction was the chosen access. Leads were removed without implanting new ones in only 4 cases: in 3, to treat an infection related to the device, and in 1 to remove a dysfunctional lead which was causing noise in an ICD. In this last case the venography showed venous occlusion. Prognostic Factors of Venographic Alterations Despite the high rate of venographic outcomes in the patients studied, it was not possible to identify prognostic factors for the occurrence of venographic alterations. The following variables were tested as probable prognostic factors: gender, age at the time of the venographic study, cardiopathy at baseline, functional class for heart failure, use of oral anticoagulants and antiplatelet agents, having an ICD lead, CIED implantation side, time since CIED implantation, number of leads implanted, left ventricular ejection, and previous procedures of reoperation (Figure 4). Discussion Venous obstructions seldom cause immediate clinical problems. However, when new leads have to be implanted, the presence of those lesions can make the procedure impossible with conventional techniques. Thus, digital subtraction venography has been mostly used because it allows identifying precisely how serious venous lesions are, as well as their location, thus allowing the planning of proper surgical strategy. 11,28-30 Figure 3 – Classification of venous lesions and collateral circulation. Examples of the four types of lesion according to the classification adopted in the study. Figure 3A: non-significant lesions characterized with obstruction of less than 50% of the blood vessel lumen and absence of collateral circulation; Figure 3B: moderate lesion in 51% to 70% of the vessel, with discrete collateral circulation; Figure 3C: severe lesion compromising 71% to 99% of the vessel with moderate collateral circulation; Figure 3D: venous occlusion with accentuated collateral circulation. 691