Cardiac Troponin I Increase After Successful Percutaneous Coronary Angioplasty: Predictors and Long-Term Prognostic Value

Abstract

After successful percutaneous coronary interventions (PCI), elevations of cardiac enzymes are not rare, but it is still not clear whether those elevations are associated with adverse late outcome. The purpose of the study was to investigate the relation between cardiac troponin I (cTn-I) increase after successful percutaneous intervention and late outcome. The study consisted of 100 consecutive patients (mean age 56 +/-9.8, 84% male) who had successful elective coronary balloon angioplasty with or without stent implantation. Patients with stable angina (n=54) and unstable angina (n=46) were included in the study. Blood samples for measurement of cTn-I were taken before and immediately after the procedure, and every 6 hours for the first 24 hours. Patients with preprocedural cTn-I elevation were excluded from the study. Postprocedural cTn-I elevation was detected in 34 patients (34%, troponin (+) group) and cTn-I levels were normal in 66 patients (66%, troponin (-) group). Logistic regression analysis showed that intervention in patients with unstable angina, stent implantation following balloon dilation, and maximal inflation pressure were the predictors of cTn-I elevation (p=0.035, p=0.038, and p=0.014, respectively). During the prospective follow-up period for 21 +/-7.5 months, the incidence of major cardiac events including recurrent angina, acute myocardial infarction, death, and revascularization were not different in patients with and without cTn-I elevation. Overall, major cardiac events occurred in 9 patients (26%) in the troponin (+) group and in 13 patients (20%) in the troponin (-) group. Kaplan-Meier survival analysis showed that cTn-I elevation was not an important correlate of overall cardiac events (log-rank: 1.66, p=0.19). The authors conclude that postprocedural cTn-I elevation is related to unstable angina, stent implantation following predilation, and inflation pressure, and there is no association with minor myocardial injury occurring after successful percutaneous coronary intervention and late adverse cardiac events.

Magnetic Resonance Imaging and Troponin Elevation Following Percutaneous Coronary Intervention

“…About 20% of patients develop elevated levels of creatine kinasemyocardial band (CK-MB) (1,2) and up to 48% of patients develop elevated troponin levels following PCI (2)(3)(4)(5)(6)(7)(8)(9). Several mechanisms related to procedural complications such as side branch occlusion, dissection, and disruption of collateral flow have been proposed for these elevations.…”

Higher incidence and serum levels of minor cardiac biomarker elevation in sirolimus-eluting stent (Cypher) than bare metal stent implantations

“…The specificity and reliability of the present methods for the determination of serum cTnI levels were well established by earlier studies [13][14][15]22]. Many studies have applied cTnI as a marker of myocardial injury in connection with PCI [23][24][25]. Furthermore, there were no significant between-group differences in clinical and lesion characteristics.…”

Lack of consensus in biomarker measurement to diagnose PCI-related myocardial infarction

“…Table I illustrates the timing of blood sampling and the prevalence of CK-MB/troponin elevations. From the figures in Table I it appears that the sampling and testing of troponin and/or CK-MB fulfilled the guidelines proposed by the joint ESC/ACC committee in six of 14 cases (6,7,9,10,12,13). In four of the studies no biomarker measurements were done prior to PCI (3,11,15,16).…”

“…No troponins were measured in three studies. The clinical importance of elevated biomarkers was addressed in six studies (8Á10, 12,13,15). In five of these elevated levels of troponin and/or CK-MB were associated with a poor clinical outcome (8Á10,12,15).…”