Long-term electrocardiographic remodeling following successful percutaneous coronary intervention for chronic total occlusion: strategy-associated patterns in antegrade and retrograde revascularization

Chronic total occlusion (CTO) causes marked myocardial ischemia and is associated with electrocardiographic remodeling and rhythm-related abnormalities. While percutaneous coronary intervention (PCI) restores perfusion, its long-term effects on electrocardiogram (ECG) changes, particularly across antegrade and retrograde strategies remain unclear. We retrospectively analyzed pre-procedural and follow-up ECGs from patients who underwent successful CTO-PCI at Guangdong Provincial People’s Hospital (2021–2023). ECG parameters including rhythm, conduction, wave morphology, and amplitudes were systematically evaluated to assess electrocardiographic remodeling before and after successful CTO-PCI and to compare follow-up ECG changes between antegrade and retrograde revascularization strategies. Multivariable regression and propensity score–based overlap weighting were performed to address baseline imbalance. A total of 196 patients (mean age 59.24 ± 10.29 years; 92.35% male) were enrolled, with a median follow-up of 13.98 [11.50-17.18] months. Rhythm or conduction abnormalities were observed in 31.63% of patients prior to PCI and in 30.10% at follow-up ( p = 0.250), with a significant increase in sinus tachycardia after PCI (0.51% vs. 4.59%, p = 0.021). Follow-up ECGs showed persistent remodeling, including a lower prevalence of abnormal Q waves (15.31% vs. 9.18%, p = 0.043), prolonged P-wave duration (75.00ms vs. 90.00ms, p = 0.003), decreased Q-wave amplitude (0.08mV vs. 0.05mV, p = 0.018), reduced R-wave amplitude in lead V1 (0.18mV vs. 0.13mV, p = 0.003), and increased S-wave amplitude in lead V5 (0.29mV vs. 0.35mV, p = 0.011). P-wave polarity shifted significantly toward inversion, with a nearly three-fold increase in prevalence (7.65% to 21.43%, p < 0.001). After multivariable adjustment, retrograde PCI was associated with higher odds of follow-up P-wave inversion (OR = 18.468, p < 0.001), lower R-wave amplitude in lead V1 (B = − 0.135, p = 0.001), greater R-wave amplitude in lead V5 (B = 0.280, p = 0.013), and a lower RV1/SV1 ratio (B = − 0.146, p = 0.039). In overlap-weighted sensitivity analyses, the associations with P-wave inversion and R-wave amplitudes in leads V1 and V5 remained significant, whereas the association with RV1/SV1 ratio was attenuated. MACCE occurred in 17.86% of patients, with no significant difference between antegrade and retrograde groups (16.33% vs. 18.37%, p = 0.747). Persistent ECG remodeling remained detectable after successful CTO-PCI, with strategy-associated patterns observed between antegrade and retrograde revascularization. These findings may assist clinicians in interpreting postprocedural ECG changes and highlight the importance of continued ECG and rhythm follow-up after CTO-PCI.