Аннотация:Background Acute post-ablation pericarditis is the most common complication of epicardial ablation of ventricular arrhythmias,while regional pericarditis following an initially uneventful endocardial catheter ablation (CA) procedure is a rareand elusive diagnosis. Case summary We report a case of a 66-year-old Russian female who developed chest pain accompanied by electrocardiogram(ECG) changes—biphasic T waves in V1–V4 leads after an initially uncomplicated premature ventricular complex CAprocedure. After examination and investigations, including transthoracic echocardiography (TTE), cardiac magneticresonance imaging (CMR) and cardiac computed tomography (CCT), she was diagnosed with regional pericarditis,which occurred even though the ablation was uneventful with the limited number of radiofrequency applications.Furthermore, the diagnosis was difficult due to normal body temperature and the absence of pericardial effusion andmyocardial abnormalities on TTE, findings that are not characteristic of pericarditis. The patient’s last office visit wasin 6 months after the procedure. Neither patient had any complaintsnor there were any changes on ECG and TTE. Discussion Regional post-ablation pericarditis is a relatively rare type of post-cardiac injury syndrome (PCIS). The varying severity of the PCIS clinical course makes the diagnosis of post-ablation pericarditis initially difficult, especially inpatients undergoing an uneventful CA procedure. Non-invasive imaging modalities as CMR and CCT should beconsidered initially in elusive cases of PCIS.