Negative current of injury due to inadvertent polarity reversal during active atrial lead implantation

We report an example of the negative current of injury (COI) during permanent pacemaker implantation. Cardiac perforation was our first priority. However, patient had stable hemodynamics, and the fluoroscopic location of the atrial lead was acceptable. Therefore, the connections were checked revealing the cause of the negative COI; the red (+) clips was attached to the tip of the atrial lead rather than anodal ring. Correcting the connections resolved the problem. This report shows that a negative COI might not only be due to cardiac perforation or right ventricular ischemia but that checking the lead connectivity should be carried out first.