Scott McTominay will undergo heart surgery for a “mild benign arrhythmia”.
Napoli confirmed the news and the Scotland midfielder will be sidelined for a short period.
Mild benign arrhythmia is described by the NHS as “when your heart beats too quickly or too slowly, or your heartbeat is not steady”.
To fix the issue, McTominay will undergo cardiac arrhythmia ablation.
The treatment involves heat or cold energy being used to create tiny scars in the heart.
This blocks faulty signals and restores a typical heartbeat.
Napoli expect the former Manchester United midfielder to be playing again after the upcoming international break.
However, this means he will miss Scotland’s upcoming matches, which are the first under new boss Sebastien Pocognoli.
The Scots play Slovenia twice, Switzerland at home and North Macedonia away in the Nations League.
McTominay will also not play as Napoli welcome Arsenal in their Champions League opener on Wednesday, September 9.