Key Clinical Message Venous spasm is an important reason for complicated or failed implantations of cardiac implantable electronic devices. Prevention or risk reduction of venous spasm during cardiac implantable electronic device implantation may be achieved by ultrasound or fluoroscopic imaging prior to puncture, cephalic vein cut‐down, sufficient pre‐ and perioperative hydration, nitroglycerin injection and effective sedation, and analgesia. Abstract This case report with literature review focuses on venous spasm as a potential cause for complicated implantations of cardiac implantable electronic devices. The case report is clinically relevant as it describes a progressive spasm affecting the axillary and the subclavian vein. A 66‐year‐old female complained of symptomatic atrial fibrillation (AF) and atypical atrial flutter despite interventional and medical treatment. As an ultimate treatment, she was scheduled for pacemaker implantation and atrioventricular node ablation. Several puncture attempts of the axillary vein failed. Despite venous blood aspiration, no guidewires could be advanced into the axillary vein. We performed a first venogram revealing significant spasm of the axillary vein. Another failed venous puncture occurred after change of access site to the subclavian vein. A second venogram displayed progression of the spasm, now affecting both the axillary and the subclavian veins. Normal saline perfusion was administered as well as intravenous isosorbide. Unfortunately, a repeated venogram after 15 min waiting time showed persistence of the spasm, still affecting both veins. The procedure was discontinued as the patient became uncomfortable. Venous spasm is an important reason for complicated or failed implantations of cardiac implantable electronic devices. Commonly used medical prevention and treatment are intravenous fluids and nitroglycerin. Prevention or risk reduction of venous spasm during cardiac implantable electronic device implantation may be achieved by ultrasound or fluoroscopic imaging prior to puncture, cephalic vein cut‐down, sufficient pre‐ and perioperative hydration, nitroglycerin injection and effective sedation and analgesia.