Correlation of postpercutaneous coronary intervention creatine kinase-MB and troponin I elevation in predicting mid-term mortality

Creatine kinase-MB (CK-MB) and troponin I elevations after successful percutaneous coronary intervention (PCI) are common, and different gradations have been correlated with mortality. To establish which of these 2 markers of myonecrosis, CK-MB and troponin I, accurately predicts mortality after successful PCI, we analyzed 2,873 patients without acute myocardial infarction who underwent PCI for in-hospital events and mid-term mortality. Patients were stratified into 4 groups based on peak post-PCI cardiac markers values: group I: normal CK-MB (<16 U/L) or troponin I (<2 ng/ml); group II: CK-MB or troponin I levels 1 to 3 times normal; group III: >3 to 5 times normal; and group IV: >5 times normal. CK-MB elevation occurred in 16.1% of patients, with 12.2%, 2.3%, and 1.6% in groups II to IV, respectively. Troponin I elevation was detected in 38.9% of patients, with 16.4%, 8.4%, and 14.1% in groups II to IV, respectively. There was poor correlation between postprocedural CK-MB and troponin I values (r = 0.10) and in their individual subgroups. Kaplan-Meier estimates of death for postprocedure CK-MB were 2.1%, 2.7%, 1.7%, and 10.3% (p = 0.002) for groups I to IV, respectively; for troponin I, these estimates were 2.2%, 2.3%, 2.9%, and 2.1% for groups I to IV, respectively (p = 0.58). A Cox proportional hazards model showed that CK-MB >5 times normal was the strongest predictor of mortality (hazard ratio 6.7, 95% confidence interval 1.9 to 22.9; p = 0.002), although heart failure, peripheral vascular disease, pre-PCI digoxin therapy, and post-PCI renal failure also predicted mortality. However, neither troponin I peak elevation nor any subgroup predicted mortality. Troponin I is frequently elevated after PCI, but does not predict mortality. Periprocedural CK-MB elevation >5 times normal remains an independent predictor of mid-term mortality and a valuable marker for PCI prognosis in low-to-medium risk patients.     

Role of cardiac troponin T in the long-term risk stratification of patients undergoing percutaneous coronary intervention.

AIMS: To investigate the long-term prognostic significance of pre- and post-procedure troponin T (TnT) elevations in patients undergoing percutaneous coronary intervention (PCI). METHODS AND RESULTS: TnT and CK-MB were measured pre- and post-procedure in 212 patients undergoing PCI. Major adverse events (composite of death, myocardial infarction and revascularization) were ascertained 6 years later. Pre-procedural TnT was a significant independent predictor of time to major events (hazard ratio [HR] 1.75, 95% confidence interval [CI] 1.16-2.64) and death or myocardial infarction. Post-procedural TnT elevation above normal was the only independent predictor of the primary end-point at 1 year (HR 2.39, 95% CI 1.09-5.26) but was not significantly related to event-free survival throughout follow-up. Post-PCI elevation of TnT 5x above normal, however, did significantly predict time to events during the entirety of follow-up. By contrast, CK-MB was not an independent predictor in any of the analyses. CONCLUSIONS: Our study confirms the long-term prognostic value of pre-procedural TnT elevation in patients undergoing PCI, and demonstrates the superior predictive ability of a post-procedural increase in TnT 5x normal for long-term adverse events. Whether the prognostic significance of smaller post-procedural TnT elevations extends beyond the intermediate-term awaits further investigation.     

Factors associated with the release of cardiac troponin T following percutaneous transluminal coronary angioplasty

Background: Recent studies have suggested that immunoassay of cardiac troponin T (cTnT) provides a more sensitive measurement of myocardial necrosis than creatine kinase MB (CK-MB) mass concentration. Hypothesis: The purpose of this study was to compare the release of cTnT and CK-MB isoenzyme in patients undergoing percutaneous coronary angioplasty, and to investigate the clinical, procedural, and angiographic correlates of abnormal elevations of both of these markers. Methods: Total creatine kinase (total CK), CK-MB, and cTnT levels were measured immediately before and 12 h following intervention in 110 patients, including 100 consecutive patients undergoing coronary angioplasty and 10 control patients undergoing diagnostic cardiac catheterization. All patients had normal levels of all three markers at baseline. A postintervention total CK level >225 U/l, an increase in CK-MB >5.0 ng/ml, and/or an increase in cTnT >0.04 ng/ml were considered indicative of myocardial injury. Results: Coronary angioplasty was successfully performed in all 100 patients without emergency bypass surgery or death, although six patients required emergent placement of an intra-coronary stent for threatened closure. Eight patients demonstrated an abnormal increase in total CK, including six who were undergoing primary angioplasty for an acute myocardial infarction. One of these patients sustained a Q-wave infarction. Post angioplasty, 18 patients had elevations of both CK-MB and cTnT, 23 had elevations of only cTnT, and the remaining 59 patients had elevations of neither. All patients with CK-MB elevation also had cTnT elevation. Neither serologic marker increased in the diagnostic catheterization control patients. In comparison with patients without postintervention cTnT rise, patients with abnormal cTnT levels had a higher incidence of complex lesion morphology (p<0.01) and intra-coronary thrombus (p ≤0.0001) prior to coronary angioplasty, and a higher incidence of coronary dissection (p≤0.01), abrupt closure (p≤0.05), and side-branch occlusion (p≤0.01) during angioplasty. In patients with elevation of both cTnT and CK-MB, postintervention CK-MB levels were 12-fold higher and cTnT levels were 21-fold higher than in patients with isolated elevation of only cTnT (p<0.01). Conclusions: These data indicate that >40% of patients undergoing coronary angioplasty have evidence of minor degrees of myocardial damage, as evidenced by cTnT release. High-risk coronary lesions and both minor and major complications of angioplasty are associated with cTnT release. cTnT appears to be a more sensitive marker of myocardial injury than CK-MB under these circumstances. In comparison with isolated cTnT rise, elevation of both CK-MB and cTnT may be indicative of greater levels of myocardial injury.     

急性ST段抬高型心肌梗死直接PCI术后ST段回落的临床研究

目的：通过观察急性ST段抬高型心肌梗塞（STEMI）直接经皮冠状动脉介入治疗（PCI）术后,梗塞相关动脉（IRA）达心肌梗塞溶栓（TIMI）血流3级患者心电图ST段回落程度,探讨ST段回落与心肌损伤及心脏收缩功能的关系。方法：选择在发病12h内接受直接PCI治疗后TIMI血流达到3级的STEMI患者115例,PCI术前、术后行心电图检查,观察ST段回落情况,术前、后测定患者肌酸激酶（CK）、肌酸激酶同工酶（CK-MB）及肌钙蛋白T（cTnT）,术后测定左室射血分数（LVEF）;按照ST段回落幅度（∑STR）不同,患者被分为两组：A组：∑STR〈50%,21例,为心肌灌注不良组,B组：∑STD≥50%,94例,为心肌灌注良好组;分析两组患者ST段回落程度与CK、CK-MB、cTnT及LVEF的关系。结果：（1）两组患者IRA部位、病变血管支数,PCI治疗前TIMI血流分级、cTnT水平,发病到PCI时间等差异均无显著性（P〉0.05）;（2）两组患者术前、后CK、CK-MB水平差异无显著性（P〉0.05）;（3）术后A组cTnT水平明显高于B组[（1.30±0.43）μg/L∶（1.0±0.45）μg/L,P〈0.05];（4）术后A组LVEF明显低于B组[（44.13±4.83）%∶（47.93±5.23）%,P〈0.05]。结论：急性ST段抬高型心肌梗塞直接PCI术后,TIMI血流达到3级,ST段回落良好的患者,心肌组织水平灌注程度较好,心肌损伤程度轻,左心收缩功能较好。     

Occurrence of non-Q wave myocardial infarction following percutaneous coronary intervention in the stent era: systematic monitoring of the three markers of myocardial necrosis

OBJECTIVES: To compare the elevation of the three markers total creatine kinase (CK), CK-MB mass, and troponin I (TnI) and their relationship with clinical and procedural characteristics following percutaneous coronary intervention (PCI). METHODS: We prospectively evaluated 385 patients consecutively undergoing successful PCI. The three markers were systematically measured before and at 6, 12, and 24 hours after PCI. Any increase above the upper normal limit (UNL) of any marker has been considered abnormal when basal values were normal, while a further increase was needed when basal values were altered. Patients with ongoing acute myocardial infarction were excluded from the analysis. RESULTS: TnI was above UNL in 183 patients (51%); in 138 (38.5%) it was the only marker altered. CK-MB mass was elevated in 12.8% patients, more than 3x UNL in 5.5% and more than 5x UNL in 2.8%. In over one half of these patients, CK-MB values peaked at 12 hours following PCI. Total CK was above UNL in 23 patients only (6.4%) and more than twice UNL in 5 (1.4%). Only 1 patient out of the 5 with CK-MB mass more than 10x UNL had total CK higher than twice UNL. In our population, post-PCI elevation of myocardial necrosis markers correlate with the occurrence of minor procedural complications (observed overall in 7.8% cases; TnI and/or CK-MB > 1xUNL 96% vs 47.5%, P < 0.001) and the presence of higher complexity clinical and/or procedural features, such as multivessel disease, multivessel or multilesion PCI, multiple stenting and use of glycoprotein IIb/IIIa inhibitors. CONCLUSIONS: The elevation of at least one biochemical marker of myocardial necrosis is frequent following successful PCI with routine stent implantation. CK-MB mass is the most practical marker, having optimal kinetic and peaking with the first 12-18 hours post-PCI. Definitive data on the prognostic role and the applicability for the diagnosis of myocardial infarction of minor elevation of CK-MB mass or isolated increase of TnI are lacking.     

Impact of Periprocedural Myocardial Biomarker Elevation on Mortality Following Elective Percutaneous Coronary Intervention

ObjectivesThis study sought to explore the association between biomarker elevation, with creatine kinase–myocardial band (CK-MB) or cardiac troponin (cTn), following percutaneous coronary intervention (PCI) and mortality in patients undergoing PCI for stable angina with normal baseline values.BackgroundSeveral studies have shown a strong association between post-PCI CK-MB elevation and subsequent mortality. However, the prognostic significance of troponin elevation following coronary intervention is still debated.MethodsPatient-level data from 5 contemporary coronary stent trials and 1 large registry were pooled. Mortality of patients with stable angina, with normal baseline biomarkers, was compared between patients with and those without different cutoff values of cTn and CK-MB.ResultsA total of 13,452 patients were included in this pooled analysis. The overall percentage of patients with elevated biomarkers following PCI was 23.9% for CK-MB and 68.4% for cTn. In the patient cohort for whom both assays were available (n = 8,859), 2.4% had both CK-MB ≥5 × the upper limit of normal (ULN) and cTn ≥35 × ULN, while 92% had both CK-MB <5 × ULN and cTn <35 × ULN. Among patients with CK-MB ≥5 × ULN (n = 315), 212 (67.3%) also had cTn ≥35 × ULN. Conversely, 390 of patients (64.8%) who had cTn ≥35 × ULN did not have CK-MB ≥5 × ULN. A total of 259 patients (1.9%) died at 1 year; 20 (7.7%) had CK-MB ≥5 × ULN, and 23 (8.8%) had cTn ≥35 × ULN. In the Cox multivariate analysis, in which the CK-MB and cTn ratios post-procedure were forced into the model, age, prior myocardial infarction, lesion complexity, hyperlipidemia, and CK-MB ratio (≥10) post-procedure were associated with increased 1-year mortality.ConclusionsFollowing elective PCI in patients in stable condition treated with second-generation drug-eluting stent, CK-MB and cTn elevations remain common. After multivariate adjustment, there was an increased mortality rate with elevation of CK-MB after PCI, whereas cTn elevation was not independently associated with mortality at 1 year.     

Superiority of combined CK-MB and troponin I measurements for the early risk stratification of unselected patients presenting with acute chest pain

BACKGROUND: Recent studies have suggested that positive troponin I tests are associated with an increased risk of cardiac death during short-term follow-up. However, it is unknown if troponin I tests alone or in addition to CK-MB measurements are superior to predict unfavorable outcome during long-term follow-up. PATIENTS AND METHODS: In a prospective, double-blind study we assessed the prevalence and prognostic value of combined troponin I and CK-MB tests in an unselected cohort of patients (n = 292) admitted to the emergency department for acute chest discomfort. Patients were grouped according to the diagnosis on discharge in those with acute myocardial infarction (1), unstable angina (2), and noncardiac chest pain (3). Six months after enrollment, death rates were obtained and follow-up interviews were performed with respect to survival, recurrence of chest pain, and myocardial infarction. RESULTS: In patients with evidence of coronary heart disease, the mortality rate for abnormal troponin I and normal CK-MB levels was 5.0%. Baseline troponin I and elevated CK-MB levels were associated with a mortality rate of 4.0%. However, the mortality rate was significantly higher (11.1%) in patients presenting with elevated troponin I and CK-MB values. In patients without myocardial infarction on admission, 10.5% with positive troponin I tests died compared to 1.6% with negative tests. The mortality rate in patients without myocardial infarction was 2.7% for patients with elevated CK-MB but normal troponin I values. In patients with both markers elevated a significantly higher mortality rate (16.7%) was found, representing a 6-fold increase in the death event rate. With the additional knowledge of troponin I values, it could be demonstrated that certain cases were misclassified as having noncardiac chest pain. At least some of the latter patients with above-normal values of troponin I were retrospectively to be reclassified as unstable angina. Acute non-Q-wave myocardial infarctions were occasionally misdiagnosed as either angina pectoris or nonischemic chest pain. CONCLUSIONS: Our data suggest the superiority of combined CK-MB and troponin I measurements in clinical practice for the early risk stratification of patients presenting with acute chest pain. In nonmyocardial infarctions, both CK-MB and troponin I convey independent prognostic information with regard to fatal outcome. Troponin I tests in addition to CK-MB measurements contribute to a lower rate of misdiagnoses.     

Baseline troponin level: key to understanding the importance of post-PCI troponin elevations.

AIMS: The adverse prognostic significance of biomarker elevations after percutaneous coronary intervention (PCI) is well established. However, often baseline troponin values are not included in the analysis or sensitive criteria are not employed. Accordingly, we assessed the timing and magnitude of post-PCI troponin T (cTnT) levels and their relationships to outcomes in patients with and without pre-PCI baseline cTnT elevations using a sensitive assay and sensitive cut-off values. METHODS AND RESULTS: cTnT was measured at baseline (pre-PCI), 8 and 16 h post-PCI in 2352 patients. A cTnT elevation was defined as > or =0.03 ng/mL. No baseline cTnT elevations were detected in 1619 patients undergoing mostly (97%) non-urgent procedures (cTnT = 0.01 +/- 0.002 ng/mL; mean +/- SD). 733 patients had baseline cTnT elevations. Only the baseline troponin value had prognostic importance. Patients with elevated cTnT baseline levels had a higher overall cumulative 12-month death/MI rate of 11.1% compared with those without elevated baseline levels of 4.7% (P < 0.05). Neither the timing nor the magnitude of the post-procedure cTnT elevations was predictive of long-term death/MI rates when baseline elevations were included in the analysis. Similar findings were observed for baseline creatine kinase-MB (CK-MB) levels. Late increases in cTnT levels (16 h post-PCI) presaged in-hospital events only. CONCLUSION: Long-term prognosis is most often related to the baseline pre-PCI troponin value and not the biomarker response to the PCI. These results support a re-evaluation of the use of biomarker data in relation to PCI.     

Significance of elevated cardiac troponin after percutaneous coronary interventions

Assays for cardiac troponin have become a standard for the diagnosis of myocardial damage. Due to their high sensitivity, minor myocardial injury can be frequently detected following percutaneous coronary interventions (PCI). Minor elevations in cardiac enzymes after apparently successful PCI are rather common and even modest increases in creatine kinase myocardial band (CK-MB) elevation identify a population with worse long-term prognosis compared to patients with no enzyme elevation. The significance of troponin elevation in acute coronary syndromes and its prognostic implications on short- and long-term clinical outcomes were previously demonstrated in several clinical studies. Conversely, data regarding troponin elevation after an apparently successful PCI is limited and their relevance in terms of predicting clinical outcomes remains unclear. Given the higher sensitivity of troponin essays, the incidence of troponin elevation after PCI is higher than that of CK-MB. In this review we discuss the significance and implications of post-procedural troponin elevation.     

Comparison of cardiac troponin T versus creatine kinase-MB for risk stratification in a chest pain evaluation unit

We evaluated cardiac troponin T (cTnT) and creatine kinase-MB (CK-MB) for risk stratification of chest pain unit (CPU) patients. We studied 383 consecutive patients with chest pain assigned to our CPU by emergency department physicians. At baseline all had normal or nondiagnostic electrocardiograms, no high-risk clinical features, and negative CK/CK-MB. CK-MB and electrocardiograms were taken at 0, 4, 8, and 12 hours and cTnT at 0, 4, and 8 hours. Eight patients (2.1%) were CK-MB positive and 39 (10.2%) were cTnT positive, including all but 1 CK-MB-positive patient. All marker-positive patients were detected by 8 hours. Seven cTnT-positive patients and 1 cTnT-negative patient had myocardial infarction (p <0.0001). cTnT-positive patients were older, less likely to be women or smokers, and more often had diabetes mellitus or known coronary disease (CAD). Seventy-one percent of patients underwent diagnostic testing. cTnT-positive patients more often underwent angiography (46% vs 20%) and underwent stress testing less often (28% vs 57%) than cTnT-negative patients. When performed, their stress tests were more often positive (46% vs 14%) and they more often had angiographically significant lesions (89% vs 49%) and multivessel disease (67% vs 29%). There were no short-term deaths. Long-term mortality was higher in cTnT-positive patients (27% vs 7%, p <0.0001). Thus, cTnT identified more CPU patients with myocardial necrosis and multivessel CAD than CK-MB and a population with high long-term mortality risk. Routine use of cTnT in CPUs could facilitate risk stratification and management.     

Long-term prognostic value of serial troponin T bedside tests in patients with acute coronary syndromes

The early presence of troponin T in serum strongly predicts short-term mortality and myocardial infarction in patients with acute coronary syndromes. We investigated the long-term outcome of the prognostic significance of the troponin T rapid bedside assay (TROPT) and compared this with the quantitative troponin T assay (cTnT enzyme-linked immunosorbent assay), myoglobin and creatine kinase-MB (CK-MB) mass. One hundred sixty-three patients with chest pain and suspected acute coronary syndromes were studied and followed prospectively for 3 years. Serial blood specimens were obtained at admission and at 3, 6, 12, 24, 48, 72, and 96 hours after admission. Patients were classified as having acute myocardial infarction in 99 patients (61%), unstable angina in 34 patients (21%), and no evidence for acute cardiac ischemia in 30 patients (18%). At 3 years, 28 patients (17%) had died of which 25 deaths (15%) were for cardiac reasons. Twenty-one patients (13%) had a nonfatal (recurrent) myocardial infarction. At admission 29% of the patients were TROPT positive (> or = 0.2 microg/L), another 31% became positive within 12 hours, and 39% remained negative. When adjusted for baseline variables, a positive TROPT (any sample 0 to 12 hours) was independently associated with a higher risk of cardiac mortality (RR 4.3, 95% confidence interval [CI] 1.3 to 14.0). Because troponin T stays elevated up to 2 weeks, later TROPT results between 24 and 96 hours remained significantly predictive for mortality. The cTnT enzyme-linked immunosorbent assay (any sample 0 to 12 hours; cutoff > or = 0.2 microg/L) was similarly predictive (RR 2.9, 95% CI 1.0 to 8.6). Early myoglobin results were significantly prognostic for cardiac mortality up to 12 hours after admission (RR 3.7; 95% CI 1.0 to 12.0). In contrast, serial CK-MB mass measurements were not predictive of mortality. Thus, a combination of a baseline TROPT and an additional TROPT 12 hours or later identifies a subgroup of patients at high risk for subsequent mortality and reinfarction, both at short-term but also at long-term.     

Impact of the elevation of biochemical markers of myocardial damage on long-term mortality after percutaneous coronary intervention: results of the CK-MB and PCI study.

AIMS: Retrospective studies and post hoc analyses have suggested that mild elevations in the creatine kinase-MB (CK-MB) isoenzyme following percutaneous coronary intervention (PCI) may be associated with an increased risk of death in the long term. However, this finding is still controversial, and the prognostic significance of elevations of more sensitive markers of myocardial damage, such as the cardiac troponins, has not been established. In this multicentre prospective cohort study, we evaluated the influence of post-procedural elevations of CK-MB and troponin I (cTnI) on long-term mortality. METHODS AND RESULTS: The CK-MB and PCI study included 3494 consecutive patients undergoing PCI from February 2000 to October 2000 in 16 Italian tertiary centres. Blood samples were collected at baseline, and at 8-12 and 18-24 h after the procedure, and were analysed in a core biochemistry laboratory. CK-MB elevation was detected in 16% of the patients, and was associated with increased 2-year mortality [7.2 vs. 3.8%; odds ratio (OR): 1.9; 95% confidence interval (CI): 1.3-2.8; P<0.001). The degree of CK-MB elevation (peak CK-MB ratio) independently predicted the risk of death (adjusted OR per unit: 1.04; 95% CI: 1.01-1.07; P=0.009). A cTnI elevation was detected in 44.2% of the cases and was not associated with a significant increase in mortality (4.9 vs. 4.0%; OR: 1.2; 95% CI: 0.9-1.7; P=0.2). CONCLUSION: Post-procedural elevations of CK-MB, but not cTnI, influence 2-year mortality.     

Prognostic value of troponin after elective percutaneous coronary intervention: A meta‐analysis

Background : Although the prognostic importance of troponin in patients with anacute coronary syndrome is clear, the significance of troponin elevation after elective percutaneous coronary intervention (PCI) is a subject of debate. However, most studies up to now had a small sample size and insufficient events during follow‐up. Methods : Electronic and manual searches were performed of studies reporting on prognosis of troponin after elective PCI. A meta‐analysis was done of all suitable studies, with death in follow‐up as primary endpoint and the combination of death or nonfatal myocardial infarction in follow‐up as secondary endpoint. Results : 20 studies involving 15,581 patients were included. These studies were published between 1998 and 2007. Overall, troponin was elevated after elective PCI in 32.9% of patients. The follow‐up period varied between 3 and 67 months (mean 16.3). Increased mortality was significantly associated with troponin elevation after PCI (4.4% vs. 3.3%, P = 0.001; OR 1.35). Furthermore, the combined endpoint of mortality or nonfatal myocardial infarction also occurred more often in patients with post‐procedural troponin elevation (8.1% vs. 5.2%, P < 0.001; OR 1.59). Conclusions : According to this meta‐analysis, troponin elevation after elective PCI provides important prognostic information. © 2008 Wiley‐Liss, Inc.     

Association of cardiac troponin, CK-MB, and postoperative myocardial ischemia with long-term survival after major vascular surgery

OBJECTIVES: The aim of this study was to determine the long-term prognosis with postoperative markers of myocardial ischemia and infarction. BACKGROUND: Cardiac troponins (cTn) are superior to creatine kinase-MB fraction (CK-MB) in detecting perioperative myocardial infarction (PMI). However, their threshold levels signifying PMI and their long-term prognostic value are not yet determined. METHODS: A cohort of 447 consecutive patients who underwent 501 major vascular procedures was prospectively studied. Perioperative continuous 12-lead electrocardiogram monitoring, cardiac troponin-I (cTn-I) and/or cardiac troponin-T (cTn-T), and CK-MB levels on the first three postoperative days, and long-term survival were determined. The association of different cutoff levels of CK-MB, troponin, and ischemia duration with long-term survival was investigated. RESULTS: Between 14 (2.9%) and 107 (23.9%) of the patients sustained PMI, depending on the biochemical criteria used. Elevated postoperative CK-MB, cTn, and prolonged (>30 min) ischemia, at all cutoff levels examined, predicted long-term mortality independent of the preoperative predictors: patient's age, type of vascular surgery, previous myocardial infarction, and renal failure (Cox multivariate analysis). Both CK-MB >10% and cTn-I >1.5 ng/ml and/or cTn-T >0.1 ng/ml independently predicted a 3.75-fold and 2.06-fold increase in long-term mortality (p = 0.006 and 0.012, respectively). Similarly, both CK-MB >5% and cTn-I >0.6 ng/ml and/or cTn-T >0.03 ng/ml independently predicted a 2.15-fold and 1.89-fold increase in mortality (p = 0.018 and 0.01, respectively). Patients with both these markers elevated had a 4.19-fold increase in mortality (p < 0.001). CONCLUSIONS: Postoperative CK-MB and troponin, even at low cutoff levels, are independent and complementary predictors of long-term mortality after major vascular surgery.     

Statin administration before percutaneous coronary intervention: impact on periprocedural myocardial infarction.

AIMS: Peri-procedural non-Q-wave myocardial infarction is a frequent and prognostically important complication of percutaneous coronary intervention (PCI). It has been postulated that statins may reduce the rate of myocardial injury after PCI. METHODS AND RESULTS: Four hundred and fifty-one patients scheduled for elective PCI and not on statins were randomly assigned to either no treatment or to statin treatment. Statin administration was started at least 3 days before the procedure.Incidence of peri-procedural myocardial injury was assessed by analysis of creatinine kinase myocardial isoenzyme (CK-MB: upper limit of normal [ULN] 3.5 ng/ml) and cardiac troponin I (cTn I, ULN 0.10 ng/ml) before, 6 and 12 h after the intervention. A large non-Q-wave myocardial infarction was defined as a CK-MB elevation >5 times ULN alone or associated with chest pain or ST segment or T wave abnormalities. Median CK-MB peak after PCI was 1.70 (interquartile ranges 1.10-3.70) ng/ml in the Statin group and 2.20 (1.30-5.60) ng/ml in the Control group (p=0.015). Median peak of cTnI after PCI was 0.13 (0.05-0.45) ng/ml in the Statin group and 0.21 (0.06-0.85) ng/ml in the Control group (p=0.033). The incidence of a large non-Q-wave myocardial infarction was 8.0% in the Statin group and 15.6% in the Control group (p=0.012: OR=0.47; 95% CI=0.26-0.86). The incidence of cTnI elevation >5 times ULN was 23.5% in the Statin group and 32% in the Control group (p=0.043: OR=0.65; 95% CI=0.42-0.98). By logistic regression analysis, the independent predictors of CK-MB elevation >5 times ULN after PCI were intra-procedural angiographic complications (OR=9.36; 95% CI=3.06-28.64; p<0.001), statin pre-treatment (OR=0.33; 95% CI=0.13-0.86; p=0.023) and age >65 years (OR=2.58; 95% CI=1.09-6.11; p=0.031). CONCLUSIONS: Pre-procedural statin therapy reduces the incidence of large non-Q-wave myocardial infarction after PCI.     

心肌肌钙蛋白T快速检测对急性心肌梗死诊断的临床应用

目的探讨心肌肌钙蛋白T(cTnT)快速检测对急性心肌梗死(AMI)的早期诊断和不良后果预测价值.方法对123名高度可疑的AMI患者在发病后24小时内系列检测cTnT和肌酸激酶同工酶MB(CK-MB)活性.结果 (1)在发病后6小时、12小时和24小时内cTnT检测AMI的敏感性分别为38.8%、85.4%和94.2%,特异性为100%;(2)在发病后6小时和24小时内,CK-MB(活性)检测AMI的敏感性分别为70%和77.7%;(3)AMI患者随着cTnT水平升高,30天死亡率显著增加(P<0.01).结论 cTnT快速检测对诊断AMI具有高度的敏感性和特异性,并能预测患者的不良后果.该方法简单快速,适宜床边检测.     

New diagnostic criteria for acute myocardial infarction and in-hospital mortality.

BACKGROUND: The recent introduction of new diagnostic criteria for acute myocardial infarction (AMI), with troponin measurement, has increased the number of patients admitted with this diagnosis. OBJECTIVE: To evaluate the epidemiologic and prognostic implications of the new diagnostic criteria for AMI. METHODS: This was a retrospective study of 586 patients admitted for acute coronary syndrome (ACS) to the coronary care unit of our hospital, between 2002 and 2003. Data were collected from RECIMA, the Madeira Ischemic Heart Disease Registry. The population was analyzed following two different definitions of ACS: 1 - old criteria (Group I): AMI with ST elevation (typical symptoms or ECG with ST-segment elevation and raised CK-MB >2x), AMI without ST elevation (typical symptoms or ECG without ST elevation and raised CK-MB >2x) and unstable angina (UA) (symptoms or ECG indicative of ischemia, with normal CK-MB, regardless of troponin status); 2 - new criteria (Group II): AMI with ST elevation (typical symptoms or ECG with segment ST elevation and raised CK-MB >2x or troponin), AMI without ST elevation (typical symptoms or ECG without ST-segment elevation and raised CK-MB >2x or troponin) and UA (symptoms or ECG indicative of ischemia, with normal enzymes). We evaluated whether this change in criteria had any influence on in-hospital mortality. RESULTS: The new criteria significantly (by 11.9 %) increased the total number of patients admitted with AMI. This was due to an increase in AMI without ST elevation (p < 0.001) and a decrease in patients with UA (p < 0.001), with no changes in AMI with ST elevation. In-hospital mortality was lower in patients with AMI diagnosed by the new criteria and in those with UA. CONCLUSION: The overall increase in AMI resulting from the new diagnostic classification was accompanied by a decrease, although not statistically significant, of in-hospital mortality, probably due to the lower risk of the population analyzed.     

Long-term prognostic value of troponin I in patients admitted to a coronary unit for unstable angina

INTRODUCTION AND OBJECTIVES: Troponin I (TnI) is a useful marker of myocardial damage for the diagnosis and prognosis of acute coronary syndrome. The purpose of this study was to analyze the long-term prognostic value of the peak TnI concentration obtained within 48 h of admission to the coronary unit for unstable angina. METHODS: The study included 149 consecutive patients. Serial determinations were made of the MB fraction of creatine kinase (CK-MB) and TnI. Patients without CK-MB elevation were classified into two groups depending on the presence of high (n = 58) or normal (n = 91) troponin I values. We prospectively analyzed the clinical and evolutive factors related to the probability of death, new acute coronary event, or coronary revascularization at one-year of follow-up. RESULTS: There were no differences in the clinical characteristics between groups, except that patients in the group with high TnI values were older (69 vs. 64 years, p = 0.01). At one year of follow-up there were no differences in the incidence of new acute coronary events or coronary revascularization procedures; however there was a higher mortality in the group with high TnI (13 vs. 4%; p = 0.01). The independent predictors of mortality were prior myocardial infarction (RR = 3), elevated troponin I (RR = 3.2), left ventricular ejection fraction < 35% (RR = 10), and age > 70 years (RR = 15). CONCLUSIONS: In patients with unstable angina a high troponin I value in the first 48 h of admission was associated with a higher mortality rate at one-year of follow-up.     

Implications of Periprocedural Myocardial Biomarker Elevations and Commonly Used MI Definitions After Left Main PCI

ObjectivesThe aim of this study was to: 1) assess the relationship of different thresholds of creatine kinase–myocardial band (CK-MB) and cardiac troponin with subsequent mortality; and 2) evaluate the prognostic significance of periprocedural myocardial infarction (PMI) according to various definitions of myocardial infarction in patients with left main (LM) coronary artery disease.BackgroundThe magnitude of postprocedural biomarker elevation representing a clinically meaningful PMI after percutaneous coronary intervention (PCI) is controversial.MethodsA total of 4,013 consecutive patients undergoing LM PCI at a single center from January 2004 to December 2016 were enrolled. CK-MB and cardiac troponin I (cTnI) were routinely collected at baseline and at frequent intervals between 8 and 48 hours after PCI. The primary and secondary outcomes were the covariate-adjusted 3-year rates of cardiovascular (CV) and all-cause mortality, respectively.ResultsThe 3-year rate of CV mortality progressively increased with higher peak CK-MB values. CV mortality was first independently predicted by postprocedural CK-MB 3 to 5 times the upper reference limit (URL) (adjusted hazard ratio [aHR]: 2.93; 95% confidence interval [CI]: 1.02-8.40), whereas all-cause death was independently predicted only by CK-MB ≥ 10 × URL (aHR: 3.25; 95% CI: 1.37-7.70). In contrast, no level of peak postprocedural cTnI was associated with CV or all-cause death. PMI by the Society for Cardiovascular Angiography and Interventions (SCAI), Academic Research Consortium-2 (ARC-2), and fourth universal definition of myocardial infarction (UDMI) occurred in 1.3%, 3.1%, and 5.1% of patients, respectively. The SCAI definition was significantly associated with 3-year CV mortality (aHR: 4.93; 95% CI: 1.92-12.69) and all-cause mortality (aHR: 3.11; 95% CI: 1.33-7.27), whereas the ARC-2 and fourth UDMI definitions were not.ConclusionsIn a large cohort of consecutive patients undergoing LM PCI, intermediate (≥3 × URL) and high (≥10 × URL) levels of peak postprocedural CK-MB independently predicted 3-year CV and all-cause mortality, respectively, whereas even large elevations of post-PCI cTnI did not. The SCAI definition (but not the ARC-2 or fourth UDMI) of PMI was independently associated with mortality after LM PCI.     

Lack of efficacy of clopidogrel pre-treatment in the prevention of myocardial damage after elective stent implantation

OBJECTIVES: The object of this study was to determine the effect of pre-treatment with clopidogrel in patients undergoing elective stent implantation. BACKGROUND: The treatment of patients with adenosine diphosphate receptor blockers after percutaneous coronary intervention (PCI) with stent implantation has been shown to decrease the incidence of subacute stent thrombosis. Furthermore, non-randomized studies on pre-treatment with clopidogrel among patients undergoing stent implantation have suggested a reduction in myocardial damage and clinical events. The effect of pre-treatment with clopidogrel has been studied in only a few randomized trials. METHODS: In a randomized trial, three days of pre-treatment with clopidogrel was compared with standard post-procedural treatment in 203 patients undergoing elective stent implantation. The primary end point was a rise in troponin I or creatine kinase-MB fraction (CK-MB) serum levels at 6 to 8 and 16 to 24 h after PCI. Secondary end points were death, stroke, myocardial infarction, coronary bypass grafting, repeated PCI, and subacute stent thrombosis at one and six months after PCI. RESULTS: No difference was found between non-pre-treated and pre-treated patients in the post-procedural elevation of troponin I (42 [43.3%] vs. 48 [51.1%], respectively, p = 0.31) or CK-MB (6 [6.3%] vs. 7 [7.4%], respectively, p = 0.78). Adjustment for possible confounding factors did not change these findings. Patient follow-up at one and six months showed no significant difference between the treatment groups in death, stroke, myocardial infarction, coronary artery bypass grafting, repeated PCI, or subacute stent thrombosis. CONCLUSIONS: In this randomized study, no beneficial effect of pre-treatment with clopidogrel on post-procedural elevation of troponin I and CK-MB or on clinical events after one and sixth months could be demonstrated. The study suggests that among patients with stable coronary syndromes in whom coronary stent implantation is planned, pre-treatment may not be beneficial in reducing early myocardial damage.