Recruitment too slow. Unrealistic to finish study with full recruitment.

The study will include patients scheduled for transvenous pacemaker- or implantable defibrillator surgery, where venous access is necessary for lead implantation. A 1:1 randomization will be performed to either standard access (at the discretion of the surgeon) or ultrasound-guided using a wireless vascular transducer (Siemens Freestyle). Primary outcome is mean time to vascular access. In addition, success rate, complication rate and total procedure time will be measured.

Pacemaker- and defibrillator lead implants typically involve vascular access via the left cephalic, axillar or subclavian vein. Gaining access is usually straight forward for an experienced surgeon/implanter, but can be difficult in a minority of cases, or for implanters with less experience. Complications include arterial puncture, pneumothorax and local bleeding or hematoma. Traditionally cephalic vein cut-down is the first choice, but is only available in 70% of cases, and for more complex procedures involving three electrodes, an additional access is always required.

Ultrasound guidance is very common in other vascular access areas such as femoral artery, radial artery and internal jugular vein, but has not gained widespread acceptance in pacemaker procedures. High quality studies, demonstrating superiority or non-inferiority over other access methods are lacking.

The present study will include all comer patients scheduled for transvenous pacemaker- or implantable defibrillator surgery, where venous access is necessary for lead implantation. A 1:1 randomization will be performed to either standard access (at the discretion of the surgeon) or ultrasound-guided using a wireless vascular transducer (Siemens Freestyle). Implanters with various degrees of ultrasound experience and pacemaker surgery experience will participate in the study. All implanters will receive a 2-hour training lecture and additional hands-on training for the first 3 cases, by an ultrasound-experienced anaesthesiologist.

Access time and success rate will be recorded, and all acute complications will be recorded. Primary outcome is mean time to vascular access. In addition, success rate, complication rate and total procedure time will be measured. Outcome data will be analyzed for the entire cohort, but also stratified for implanter and excluding the first 10 cases for each implanter, to compensate for various experience and individual learning curve.

Inclusion Criteria:

• Planned pacemaker or implantable defibrillator surgery with at least one new transvenously placed lead.

Exclusion Criteria:

• Difficult vascular access known before surgery, where special access technique is planned or required.