LDL-C and Total Stent Length are Independent Predictors of Periprocedural Myocardial Injury and Infarction for Unstable Angina Patients Undergoing Elective Percutaneous Coronary Intervention

BACKGROUND: To investigate the predictive value of low-density lipoprotein cholesterol (LDL-C), total stent length and number of implanted stents in patients with unstable angina (UA) regarding myocardial injury and infarction during perioperative period. METHODS: Three hundred and fifteen consecutive UA patients between January 2015 and June 2018 were retrospectively recruited from two cardiac centers of Hebei Province, China. These patients had normal preprocedural cardiac troponin I (cTnI) and underwent uneventful revascularizations. The predictive value of baseline LDL-C level and total stent length was investigated by linking to post procedural cTnI value in this cohort. Meanwhile, other related clinical and procedural variables were analyzed. RESULTS: Baseline LDL-C level or LDL-C grade was correlated with post percutaneous coronary intervention (PCI) cTnI levels (r = 0.120, P = 0.01; r = 0.157, P = 0.004). LDL-C grade was an independent risk factor of perioperative myocardial injury and infarction (P < 0.05) after multivariable adjustment. The risk increased with the elevation of baseline LDL-C level. Compared to the lowest level group (<70 mg/dl), the group with 70–99 mg/dl carried three times higher risk (OR = 3.318; 95% CI: 1.167–9.436; P < 0.05). And, patients with LDL-C level ≥100 mg/dl had the worst prognosis (OR = 4.783; 95% CI: 1.736–13.180; P = 0.002). Besides, the study also found that the total length of stent was predictive of perioperative myocardial injury and infarction independently (OR = 1.037; 95% CI: 1.017–1.058; P = 0.001). CONCLUSION: Baseline LDL-C level and total stent length were independent predictors of periprocedural myocardial injury and infarction in UA patients undergoing elective PCI.