Acute Innominate Vein Dissection During Pacemaker Revision Procedure: A Case Report and Conservative Management.

Iatrogenic central venous dissection during cardiac pacing procedures is exceptional. We present the case of a 75-year-old woman with a single-chamber pacemaker since 2004, who underwent generator replacement and new ventricular lead implantation in 2025. During the procedure, anomalous resistance to lead advancement was identified. Immediate venography revealed innominate vein dissection with intramural hematoma. The procedure was discontinued, and the patient remained stable. Computed tomography angiography at 24 hours confirmed complete occlusion of the left subclavian and innominate veins due to thrombotic progression. Conservative management with deferred anticoagulation was adopted after confirming clinical stability and absence of pericardial effusion progression. Given that the patient was not pacemaker-dependent (ventricular pacing, 2.6%) and the existing ventricular lead retained adequate electrical parameters, a new generator was connected to the previous lead without adding a new lead, deferring any further transvenous implantation attempt to avoid additional manipulation of the recently injured venous system. The patient evolved favorably, with confirmation of right contralateral access patency as a viable alternative for potential future implantation if clinically required. This case illustrates the importance of early recognition of acute venous injuries and individualization of therapeutic management.