Background: Myocardial necrosis complicates one-third of percutaneous coronary intervention (PCI, MI4a) and may adversely affect the outcome. We assessed the angiographic variables associated with MI4a that may help to identify those at highest risk.
Methods and results: Cardiac troponin-I (cTnI) was measured after PCI in 243 patients undergoing elective PCI. Patients were grouped according to post-procedure cTnI result: minor or no elevation (<0.1 ng/ml), PCI-related MI4a (0.1 to <0.78 ng/ml) and WHO defined MI by the Troponin-I Ultra method (>or=0.78 ng/ml). Angiographic variables were analyzed in blinded manner and correlated with cTnI rise. Minor or no cTnI elevation after PCI occurred in 116 of 243 (48%) patients, MI4a in 65 of 243 (27%) and WHO defined MI in 62 of 243 (25%). Independent predictors of MI4a included stent length [odds ratio (OR) 1.04 per mm; P=0.0015], X-ray screening time (OR 1.05 per minute; P=0.016) and procedural chest pain requiring opiates (OR 7.92; P=0.00066). The stenting of proximal vessel segments with fewer collaterals (large myocardial area at risk), diminished myocardial perfusion (P=0.0065) and side branch compromise were associated with cTnI elevation. Clinical events were more frequent following MI4a (9.4 vs. 3.4%, P=0.07).
Conclusion: These data show that cTnI release after elective PCI is predominantly related to stent length. Minimizing the stent length deployed may reduce the cTnI release and improve prognosis.