Prediction of troponin elevation by means of intracoronary electrocardiogram during percutaneous coronary intervention of coronary bifurcation lesions (from COronary SIde Branch Residual IschemiA and COllateralization Assessment Study; COSIBRIA & Co Study)

Background: The influence of periprocedural ischaemia on coronary artery bifurcation stenting (percutaneous coronary intervention [PCI]) remains uncertain. Aim: To determine the differences in rates of end procedural ischaemia after bifurcation lesion PCI detected with intracoronary electrocardiography (icECG). Methods: Unipolar icECGs were recorded before, during, and after stent placement and at the end of procedure in side branch (SB) and main branch (MB). Coronary wire was placed in all distal vessels with diameter > 1.5 mm to map the distal zones of ischaemia. The patient population consisted of patients with stable/unstable angina with troponin I evaluated before and after PCI. Results: We studied 147 patients (68% males) with mean age of 64 +/- 9 years. One hundred and forty-two patients had icECG recordings at the end of PCI from all locations of the treated region; 36% of patients had MB ST segment elevation (STE) and 31% had icECG STE in the SB region (p = 0.378). The icECG had sensitivity of 82% and specificity of 81% to detect troponin I elevation, with positive predictive value of 81% and negative predictive value of 83%. The independent predictors of troponin increase (> 5 x N) were: sex (for female gender, OR = 0.130, CI 0.017-0.995, p = 0.049), previous myocardial infarction (OR = 33.23, CI 2.802-394.1, p = 0.005), and icECG STE in MB or SB or occlusion of secondary SB (OR = 7.877, CI 2.474-25.07, p < 0.001) and for any troponin elevation were double product - SBPxHR (OR = 0.999, CI 0.999-1.00, p = 0.022) and icECG STE in MB or SB or occlusion of secondary SB (OR = 9.762, CI 3.273-29.12, p < 0.001). Conclusions: Intracoronary electrocardiography is a highly sensitive and specific method for determination of ischaemic regions and prediction of elevated troponin I.