OBJECTIVETo observe the incidence of ischemic J wave before and post percutaneous coronary intervention (PCI) in patients with coronary heart disease (CHD).

METHODSCHD patients (n = 117) underwent percutaneous coronary intervention (PCI) in Shanxi cardiovascular hospital were included in this study. The 12-lead ECGs were recorded within 24 hours before and after PCI. The ischemic J waves of five lead-groups (II, III, aVF group: V(1), V(2) group; V(3), V(4) group; V(5), V(6) group;I, aVL group) were analyzed and the number of lead-groups with J waves (0 - 5) were obtained in each patient. According to time course or wave amplitude, J waves were classified into three grades: small (time course between 0.02 - 0.03 s or wave amplitude between 0.05 - 0.09 mV), large (time course between 0.04 - 0.06 s or wave amplitude between 0.10 - 0.20 mV) and enormous (time course > 0.06 s or wave amplitude > 0.20 mV) J waves.

RESULTSThe number of lead-groups with ischemic J waves (0 - 5) in each patient was similar between pre and post PCI in the 117 patients (χ(2) = 6.23, P = 0.285). The numbers of small, large and enormous J waves were 157, 36 and 9 respectively before PCI and 163, 20 and 5 after PCI. The incidence of small J waves increased (77.72% vs. 86.70%) while large and enormous J waves decreased (17.82%, 4.46% vs. 10.64%, 2.66%) post PCI (χ(2) = 5.28, P < 0.05).

CONCLUSIONSThe numbers of lead-groups with ischemic J waves were similar before and post PCI. However, the amplitude of ischemic J waves decreased after PCI suggesting PCI could improve ischemic J waves in CHD patients.