Navigating challenges: Cleidocranial dysplasia and complexities in transvenous pacemaker implantation.

Cleidocranial dysplasia (CCD) is a rare genetic disorder characterized by skeletal abnormalities, including hypoplastic or absent clavicles, delayed closure of cranial sutures, and dental anomalies. We present a case of a 72-year-old female with a history of breast cancer treated with mastectomy and radio chemotherapy with the port-a catheter still in place in the left subclavian region. She presented to the emergency room with syncope related to a complete atrioventricular (AV) block. The patient underwent temporary pacing via femoral access while awaiting definitive pacemaker implantation. The absence of the right clavicle, first observed during prepuncture fluoroscopy and later confirmed on postprocedure imaging, significantly influenced the approach to pacemaker implantation. Venography played a crucial role in visualizing the venous trajectory and guiding the puncture, ensuring successful lead placement. The procedural challenges encountered due to the patient's skeletal anomalies highlight the importance of individualized approach and careful consideration of anatomical variations in interventional cardiology procedures.