Background: Implantation of a cardiac pacemaker may be indicated in patients with a significant bradycardia according to current guidelines.1 Annually, around 691 pacemakers per million inhabitants are implanted in Sweden.2 A pacemaker system consist of one or two leads connected to a device that is implanted beneath the collarbone.3,4 Vessel access is typically on the left side through the cephalic, axillary or subclavian vein. The pacemaker is inserted into a pocket. Routinely this pocket is just above the pectoral fascia (subcutaneously) or sometimes in skinny patients with a small amount of subcutaneous fat between the pectoral muscular layer (intramuscular). Even though technical developments have diminished the size of pacemakers markedly over time, complications due to superficial implants still do occur.5,6 Occasionally the device erode the skin and a complete extraction of the system is necessary. More frequently patients complain about the device being too superficial which sometimes require surgical repositioning of the device.5,6 The device may create discomfort, pain, and unsightly.5,6 The lateral corner of the device may disturb the shoulder movement, sleep and the leads can be turned within the pocket (Twiddler's syndrome). Minor branches from the supraclavicular nerves may result in discomfort. When vessels from the subcutaneous adipose tissue are distorted, extensive bruising may be bothersome and a large hematoma is a known risk of infection. The perfusion in the operation area is diminished and the amount of fat over device may be reduced to an extent that was unexpected at first implant. The change of device due to battery depletion can result in even less surrounding tissue. An alternative approach is an intramuscular placement of the device.7,8 This has been advocated by Kistler et al based on personal experience but there are neither systematic observational studies nor randomized controlled studies to support this approach.6 To the knowledge of the investigators no randomized controlled trial have addressed the question about the optimal placement of a bradycardia pacemaker.