Pacemaker-lead-associated thrombosis in dogs: a multicenter retrospective study

Pulmonary Thromboembolism and Myocarditis Resulting from a Large Pacing-Lead-Associated Right Ventricular Thrombus in a Dog with Chronic Cough as Presenting Sign

“…As pacemaker-lead-associated thrombosis often remains clinically silent, the real incidence of this complication in both humans and dogs is unknown. Human studies report it in up to 45% of cases [ 11 , 12 , 16 , 21 ], and the recently published multicenter study on dogs reported an incidence of 10% in 260 dogs [ 10 ]. In case the pacemaker-lead-associated thrombosis leads to clinical signs, typically due to congestion, treatment can be warranted [ 21 , 22 , 23 ].…”

“…Protein-losing nephropathy is a known predisposing factor for thrombus formation via losing circulating antithrombin [ 10 , 25 , 26 ]. Whether the present dog had proteinuria at the pacemaker implantation or it developed later remains unknown, as no urinalysis was performed before pacemaker implantation to screen for protein-losing nephropathy.…”

“…Because having a pacemaker implanted is not an indication for echocardiography during the rechecks in an asymptomatic dog, this was not performed in the present case either. However, this practice might be changed in future cases based on the findings of the present dog and recent literature [ 10 ], especially because with echocardiography a thrombus caused by any hypercoagulable states (such as hyperadrenocorticism or neoplasia) can be detected.…”

“…Pacemaker implantation has numerous possible complications, the most common being lead dislodgement, infection of the pulse generator or the lead, right ventricular wall perforation, and several technical problems with the pacing lead or pulse generator [ 5 , 6 , 7 ]. Thrombus formation around the intravascular or intracardiac parts of the permanent pacemaker lead has been incidentally reported in larger studies and in a few case reports in dogs [ 1 , 5 , 6 , 7 , 8 , 9 ], but this complication had not received sufficient attention until a recently published multicenter study that focused on this aspect [ 10 ]. According to the authors’ knowledge, there is no detailed report about the clinical course and post-mortem findings of pacemaker-lead-associated thrombosis and subsequent pulmonary thromboembolism in dogs.…”