Placement Of Cardiac PacemaKEr Trial (POCKET) - rationale and design: a randomized controlled trial.

Background: A pacemaker system consists of one or two leads connected to a device that is implanted into a pocket formed just below the collarbone. This pocket is typically subcutaneous, that is, located just above the pectoral fascia. Even though the size of pacemakers has decreased markedly, complications due to superficial implants do occur. An alternative technique would be intramuscular placement of the pacemaker device, but there are no randomized controlled trials (RCTs) to support this approach, which is the rationale for the Placement Of Cardiac PacemaKEr Trial (POCKET). The aim is to study if intramuscular is superior to subcutaneous placement of a pacemaker pocket.

Methods: In October 2016, we started to enroll 200 consecutive patients with an indication for bradycardia pacemaker implantation. Patients are randomized to random block sizes, stratified by age group (cut-off: 65 years) and sex, and then randomized to either subcutaneous or intramuscular implant. A concealed allocation procedure is employed, using sequentially numbered, sealed envelopes. Pocket site is blinded to the patient and in all subsequent care. The primary endpoint is patient overall satisfaction with the pocket location at 24 months as measured using a visual analog scale (VAS) 0-10. Secondary endpoints are: complications, patient-reported satisfaction at 1, 12, and 24 months (overall satisfaction, pain, discomfort, degree of unsightly appearance, movement problems, and sleep problems due to device).

Conclusions: POCKET is a prospective interventional RCT designed to evaluate if intramuscular is superior to subcutaneous placement of a bradycardia pacemaker during a two-year follow-up.