A b s t r a c t
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 × 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.
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INTRODUCTIONCoronary bifurcation lesions remain a major therapeutic challenge with high early and late complication rates. It has been shown that angiographically high grade ostial side branch (SB) stenosis is not flow limiting and may not cause ischaemia. Our studies with delayed gadolinium enhancement magnetic resonance imaging before and after bifurcation percutaneous coronary intervention (PCI) demonstrated that occurrence of angiographic stenosis of more than 70% in diameter is associated with periprocedural myonecrosis in the region of SB [1]. Moreover, the post-procedural myocardial injury after uncomplicated PCI is not uncommon [2-4] with a frequency of 5% to 30%. Although this is thought to have no clinical significance, clinical trials demonstrated an increased risk of adverse cardiac events in patients with periprocedural myonecrosis [5].The unipolar intracoronary electrocardiogram (icECG) recording from angioplasty guidewire represents local epicardial ECG and has been shown to be more sensitive and more reliable in detecting regional myocardial ischaemia during balloon inflation than standard ECG [6][7][8][9][10]. The icECG detects earlier ischaemia and the changes are more prominent than surface ECG. The wire...