Electrocardiography
Electrocardiogram (ECG) is a technology that records the changes in cardiac electrical activity during each cardiac cycle from the body surface[41]. It can not only reflect the changes in the heart rhythm, but also has a prompting effect on pericarditis, especially for patients with CP who are not accompanied by pericardial thickening or calcification. Morris first introduced the P-wave terminal force (PTF) in lead V1 (PTFV1) measured by 12-lead ECG that can reflect left atrial structural abnormalities and diastolic dysfunction of left ventricular[42]. Yanhong Ren’s study[43] indicated a close association of abnormal PTFV1(≤-0.04mm·s) and TBCP, which could remedy the limitation of X-ray, CT, and echocardiography examination in the TBCP diagnosis. The abnormality of PTFV1 may associated with the load increasing of the left atrial and the right atrial, leading to an prolongment of the left atrial depolarization and the interatrial bundle conduction interval. What’s more, low voltage and atrial fibrillation may be present in part of patients with CP.