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

Prevention of minor myocardial injury after elective percutaneous coronary intervention: comparison of ticagrelor versus clopidogrel

BACKGROUND

Elective percutaneous coronary intervention (ePCI) may cause minor elevation of cardiac enzymes, so-called minor myocardial injury (MMI) which can be due to different pathophysiological mechanism (e.g. distal embolisation, side branch occlusion, increased platelet activation triggered by the intracoronary metallic stents). We aimed to compare the effectiveness of ticagrelor versus clopidogrel for the prevention of MMI and major adverse clinical events (MACEs) after ePCI.

METHODS

Study population consisted of two groups of patients based on the treatment: Group I, receiving clopidogrel (n = 104), Group II, receiving ticagrelor (n = 96). Cardiac troponin I (cTnI), CK-MB were studied before and 12 hours after the procedure. Elevation of cTnI greater than 0.06 ng/ml was considered as MMI. All patients were also evaluated for the MACEs (death, myocardial infarction, stroke and transient ischaemic attack).

RESULTS

Fifty-two of 200 patients (26%) had MMI after the procedure. The minor myocardial injury was significantly more prevalent in clopidogrel group than that of ticagrelor group (33% vs. 19%, p = .03). Myocardial infarction (MI) and MACEs were significantly higher in the clopidogrel group (15% vs. 6%, for MI, p = .04; 16% vs. 6%, for MACEs, p = .03, respectively). Multivariate analysis demonstrated antiplatelet treatment, saphenous graft intervention, type-C lesion as independent predictors of MMI.

CONCLUSIONS

Present study showed that the combination of ticagrelor and aspirin was more effective than combination of clopidogrel and aspirin in decreasing MMI and MACEs after elective stenting.

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

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.

Effects of Direct Stent Implantation and Conventional Stent Implantation on Minor Myocardial Injury

Direct coronary stenting without balloon predilation has the potential benefits of a reduced risk of extended dissections, reduced fluoroscopy exposure, reduced procedural time, and potential cost savings. The purpose of the study was to compare the effects of angiographically successful direct stent implantation and conventional stent implantation (stent implantation following predilation) on minor myocardial injury characterized by cardiac troponin I (cTn-I), and cardiac troponin T (cTn-T) elevation. The authors prospectively studied 42 patients who had successful direct stent implantation, and 49 patients who had successful conventional stent implantation. Blood samples for measurement of cTn-I and cTn-T were taken before, and immediately after the procedure, and every 6 hours for the first 24 hours. cTn-T elevation was observed in 6 patients (14.3%) in the direct stent implantation group, and in 16 patients (32.6%) in the conventional stent implantation group (p: 0.03). Similarly cTn-I elevation was more frequent in the conventional stent implantation group (20 patients, 40.8%) than direct stent implantation group (7 patients, 16.7%, p: 0.02). Stent implantation following predilation is more frequently associated with postprocedural minor myocardial injury than direct stent implantation.

Risk factors of cardiac troponin T elevation in patients with stable coronary artery disease after elective coronary drug-eluting stent implantation

BACKGROUND

Cardiac troponin T elevation after coronary intervention has been demonstrated to be associated with the prognosis of coronary artery disease (CAD). However, there were few studies about comprehensive risk factors analysis of troponin T elevation after elective drug-eluting stent (DES) implantation.

HYPOTHESIS

The prognosis of CAD after coronary interventions was associated with clinical and procedural risk factors of CAD, such as age, hypertension, severity extent of CAD and so on.

METHODS

From March to December in 2010, patients with stable CAD were admitted for elective coronary intervention in our hospital. They were divided into an elevated troponin T group and a normal troponin T group by postprocedural troponin T. Clinical factors, laboratory-test factors, and angiographic factors (such as gender, age, cholesterol, Gensini score, and others) were analyzed.

RESULTS

A total of 209 patients with an average age of 64.0 ± 9.9 years were enrolled in the study: 70 patients with elevated troponin T (≥0.03 ng/mL) after DES implantation and 139 patients with normal troponin T (<0.03 ng/mL). After univariate analysis, we found that age, hypertension, total cholesterol, low density lipoprotein-cholesterol (LDL-C), Gensini score, number of stenosed vessels, and total implanted stents were associated with postprocedural troponin T elevation. According to the results of multivariate analysis, we found that age, total cholesterol, number of stenosed vessels, and number of implanted stents were independent risk factors of postprocedural troponin T elevation.

CONCLUSIONS

Age, serum total cholesterol, number of stenosed vessels, and number of implanted stents could be independent risk factors of troponin T elevation after elective DES implantation.

Prognostic value of cardiac troponin-I or troponin-T elevation following nonemergent percutaneous coronary intervention: a meta-analysis

OBJECTIVES

The aim of this meta-analysis was to assess the prevalence and prognostic value regarding mortality of cTnT or cTnI elevations after nonemergent percutaneous coronary intervention (PCI) in a large number of cohort/registry studies.

BACKGROUND

Routine cardiac troponin measurement after elective PCI has been controversial among interventionalists. Recent studies have provided conflicting data in regard to predictive value of cardiac troponin-T (cTnT) and troponin-I (cTnI) elevation after non-emergent PCI.

METHODS

Electronic and manual searches were conducted of all published studies reporting on the prognostic impact of cTnT or cTnI elevation after elective PCI. A meta-analysis was performed with all-cause mortality at follow-up as the primary endpoint.

RESULTS

We identified 22 studies, involving 22,353 patients, published between 1998 and 2009. Postprocedural cTnT and cTnI were elevated in 25.9% and 34.3% of patients, respectively. Follow-up period ranged from 3 to 67 months (mean: 17.7 ± 14.9 months). The results showed no heterogeneity among the trials (Q-test: 25.39; I(2) : 17%; P = 0.23). No publication bias was detected (Egger's test: P = 0.16). The long-term all-cause mortality in patients with cTnI or cTnT elevation after PCI (5.8%) was significantly higher when compared to patients without cTnI or cTnT elevation (4.4%); OR 1.45 (95% CI: 1.22-1.72), P < 0.01. In addition, the postprocedural composite adverse clinical events of all-cause mortality or myocardial infarction (MI) in patients with cTnI or cTnT elevation after PCI (9.2%) was significantly higher when compared to patients without cTnI or cTnT elevation (5.3%); OR 1.77 (95% CI: 1.48-2.11), P < 0.01.

CONCLUSIONS

The current meta-analysis indicates that cTnI or cTnT elevation after nonemergent PCI is indicative of an increase in long-term all-cause mortality as well as the composite adverse events of all-cause mortality and MI. Efforts to routinely monitor periprocedural cTn levels along with more intensive outpatient monitoring/treatment of patients with cTn elevations may help to improve the long-term adverse outcomes in these patients following non-emergent PCI.

Troponin ratio and risk stratification in subjects with acute coronary syndrome undergoing percutaneous coronary intervention

BACKGROUND

Cardiac enzyme release after percutaneous coronary intervention (PCI) seems to play a role in risk stratification. After PCI, CK-MB plasmatic concentrations three times above the upper level of normal (ULN) are currently the most used risk stratification parameters. We sought to assess whether peak cardiac troponin I (cTn-I) concentration/base concentration ratio (PBTR) may act as a predictor of major adverse cardiac events (MACEs) after PCI, regardless of cTn-I ULN.

METHODS

We evaluated 326 consecutive patients with acute coronary syndrome (ACS) who underwent PCI. Baseline and post-PCI cTn-I values were evaluated over serial blood samples every 6h for at least 72h. Patients were further divided into four groups according to their PBTR values (<1, 1-4, 4-10, >10). MACEs were recorded over a 6-month follow-up period. Patients with primary PCI or unsuccessful PCI were excluded from the study.

RESULTS

Higher values of PBTR significantly correlated with a worse prognosis at 6 months (<1, 16.30% of MACEs; 1-4, 19.42%; 4-10, 24.39%; >10, 35.63%; p<0.05), both in Q-wave myocardial infarction (MI) and unstable angina (UA) subgroups. The correlation remained statistically significant, even considering subjects with peak cTn-I less than three times the ULN (p < 0.05) and after correction for age, gender, risk factors, diagnosis (MI versus UA), and peak cTn-I levels in a multiple Cox' regression analysis (HR 1.62, p<0.05).

CONCLUSIONS

PBTR is an independent predictor of MACEs after PCI in a 6-month follow-up period. This risk stratification tool may be useful to predict adverse events in PCI patients, even in the case of apparently non-elevated peak cTn-I concentrations.

Peri-procedural myocardial injury: 2005 update

During the past three decades, percutaneous coronary intervention has become one of the cardinal treatment strategies for stenotic coronary artery disease. Technical advances, including the introduction of new devices such as stents, have expanded the interventional capabilities of balloon angioplasty. At the same time, there has been a decline in the rate of major adverse cardiac events, including Q-wave acute myocardial infarction, emergency coronary artery bypass grafting, and cardiac death. Despite these advances, the incidence of post-procedural cardiac marker elevation has not substantially decreased since the first serial assessment 20 years ago. As of now, these post-procedural cardiac marker elevations are considered to represent peri-procedural myocardial injury (PMI) with worse long-term outcome potential. Recent progress has been made for the identification of two main PMI patterns, one near the intervention site (proximal type, PMI type I) and one in the distal perfusion territory of the treated coronary artery (distal type, PMI type II) as well as for preventive strategies. Integrating these new developments into the wealth of clinical information on this topic, this review aims at giving a current perspective on the entity of PMI.

Elevated troponin-I after percutaneous coronary interventions: Incidence and risk factors

BACKGROUND

Percutaneous coronary interventions (PCIs) are often complicated by postprocedural myocardial necrosis as manifested by elevated cardiac markers.

PURPOSE

To assess the incidence and risk factors of elevated troponin-I (TnI) after PCI.

METHODS AND RESULTS

We performed a retrospective analysis on 522 PCI cases over a 1-year period at a single center. An elevated postprocedural TnI (>1.0 ng/ml) occurred in 213 patients (40.8%). Overall, glycoprotein (GP) IIb/IIIa inhibitors were used in 52% of cases. Baseline clinical characteristics were similar between the positive and the negative TnI groups. A univariate analysis revealed that patients with elevated TnI post-PCI had significantly more multivessel (28% vs. 15%, P = .001) and multilesion interventions (44% vs. 27%, P<.0001). The lesions were longer, more often angulated and involving bifurcations, and more complex in the TnI-positive group. Stent use and number of stents was higher in the TnI-positive group, and longer inflation times (>30 s) or higher inflation pressures (>14 atm) were used more often in the TnI-positive group. GP IIb/IIIa inhibitor use was higher in the TnI-positive group (61% vs. 45%, P = .0007). After multivariable analysis, independent predictors of elevated TnI after PCI included multilesion intervention, lesion length, lesion angulation, and GP IIb/IIIa inhibitor use.

CONCLUSION

TnI is elevated in approximately 40% of cases after PCI. TnI is more likely to be elevated after intervention on multiple lesions, angulated or long lesions.

Role of cardiac troponin testing in percutaneous transluminal coronary angioplasty

Percutaneous transluminal coronary angioplasty (PTCA) is a common invasive procedure for myocardial revascularization. This article reviews the role of monitoring cardiac troponins in identifying procedural myocardial damage as a result of PTCA, its associations with balloon inflation time, stenting, side-branch occlusion and the prognostic implications of elevated levels of cardiac troponins. A review of several studies demonstrates that cardiac troponins are more sensitive than creatine kinase MB, CK-MB (mass) in detecting minor myocardial damage during PTCA. Increases in post-procedural cardiac troponin T and cardiac troponin I are associated with a greater degree of morbidity and mortality. Increases are more common and more pronounced following a longer duration of balloon inflation time, stenting and side-branch occlusion. Elevated cardiac troponins pre-procedure are a poor prognostic indicator.

The prevention of minor myocardial injury with ticlopidine pretreatment in patients undergoing elective coronary stenting

The aim of the study was to determine whether ticlopidine treatment prior the coronary stenting would be associated with lower rates of procedure-related minor myocardial injury (MMI) in patients undergoing elective coronary stenting. In this retrospective, nonrandomized, uncontrolled study, a total of 153 consecutive patients with a mean age of 63.4+/-8.9 years were divided into two groups based on the duration of ticlopidine treatment: group I (n=81), ticlopidine >/=3 days before the procedure, group II (n=72), on the same day as stent placement. Cardiac troponin T (cTnT) was measured immediately before and 12 h after the procedures. All patients were followed-up during the hospital stay with respect to MMI and major clinical events (MCE). The increase frequency and the amount of cTnT level in group I was found to be significantly lower compared with group II (4 vs. 13; P<0.01, and 0.35+/-0.06 vs. 0.52+/-0.11 ng/ml; P<0.01, respectively). In general, patients with elevated cTnT levels are more likely to have C type lesion and multivessel procedure than those of normal cTnT level (41 vs.10%; P<0.002 and 47 vs. 17%; P<0.009, respectively). Though there was a trend toward increased MCE rates in group II than that of group I, this did not reached statistical significance (3 vs.1; P=NS). The present study shows that an anti-platelet treatment with ticlopidine prior the coronary stenting of adequate duration to allow for the development of maximal inhibition is associated with a markedly decreased incidence of procedure-related MMI. Therefore, ticlopidine pretreatment may be a cost alternative for the prevention of platelet-rich microembolism in patients undergoing elective coronary stenting.

Comparison of clopidogrel versus ticlopidine for prevention of minor myocardial injury after elective coronary stenting

We searched a randomized, double-blinded, prospective study that compared the effectiveness of clopidogrel versus ticlopidine for prevention of minor myocardial injury (MMI) and major clinical events (MCEs) after elective coronary stenting. A total of 158 consecutive patients (98 male, 60 female patients with a mean age of 59.3+/-5.4 years) were divided into two arms based on treatment with thienopyridines: group I, clopidogrel 1 x 300 mg as a loading dose, and 1 x 75 mg per day thereafter, group II, ticlopidine 2 x 250 mg daily. Both thienopyridines were started on the same day as stent placement. Cardiac troponin T (cTnT) was measured immediately before and 12 h after the procedures. All patients were followed-up during the hospital stay (6+/-2 days) with respect to MMI and MCEs. The increase frequency and the amount of cTnT level in group I was found significantly lower compared with group II (5 vs.15; P<0.01; 0.38+/-0.11 vs. 0.44+/-0.12 ng/ml; P<0.001, respectively). Patients with elevated cTnT levels more likely to have C type lesion (P<0.004). Though there was a trend toward increased major clinical events rate in group II than those of group I, the statistical difference was not different (4 vs. 1.3%; P>0.05). The present study showed that the combination of clopidogrel and aspirin was more effective than the combination of ticlopidine and aspirin in decreasing the rate of MMI.

Cardiac troponins and creatine kinase content of striated muscle in common laboratory animals

Animal models are important for the investigation of human heart pathology, novel treatments, and medical or surgical interventions for disease. Serum markers of myocardial damage may also be important tools within this field of research. In order to assess the cardiac specificity of widely utilised serum markers, we measured the cardiac troponins and creatine kinase (CK) isoenzymes in cardiac and skeletal muscle samples taken from dog, monkey, pig and rat. These samples were also analysed by immunoblotting for cardiac troponin I (cTnI) and cardiac troponin T (cTnT). The content of cTnI and cTnT in skeletal muscle was below 0.6% of that found in heart for all animal species studied. This low immunoreactivity in skeletal muscle was confirmed by immunoblot analysis. The content of CK was higher in skeletal muscle than in heart muscle for all species. The CK-MB/total CK ratio was lower in skeletal muscle than in cardiac muscle for all species. The differences in CK-MB content of skeletal muscle and heart muscle were much less pronounced than the tissue differences in the amounts of the cardiac troponins. The cardiac troponins are potentially useful serum markers of myocardial damage, with high specificity for myocardial muscle in these common laboratory animals. Creatine kinase-MB is much less cardiac-specific.

Monitoring plasma cardiac troponin I for the detection of myocardial injury after percutaneous transluminal coronary angioplasty

The objective of this study was to detect myocardial injury defined by an increase of plasma cardiac troponin I (cTnI) following percutaneous transluminal coronary angioplasty (PTCA) and compare plasma cTnI with the risk of cardiac complications at 30 days. Plasma cTnI, creatine kinase (CK) MB, and total CK were determined in 83 patients before (baseline) and 6, 12 and 24 h after PTCA. Thirty-eight patients underwent conventional PTCA, 39 PTCA-stent and six rotational atherectomy. Patients with acute myocardial infarction (AMI) and increased pre-procedural cTnI >0.8 microg/l were categorized into group 1 (n=23). The remaining 60 patients (pre-procedural cTnI=0.8 microg/l) were categorized as follows: group 2 (n=15) AMI; group 3 (n=20) unstable angina (UA); group 4 (n=25) coronary artery disease (CAD). Twelve hours post-procedure, all three cardiac markers were more frequently increased over baseline in group 2 patients (40-60%) compared to patients in group 3 (5-29%, P<0.03) or group 4 (0.5-5%, P<0.01). This was also true for patients undergoing PTCA-stent compared to conventional PTCA or rotational atherectomy (27-40 vs. 4-14%, P<0.02). cTnI was more sensitive (60%) to detect release of myocardial protein after PTCA compared to total CK (47%) or CKMB (43%). A moderate increase of cTnI (0.8-1.5 microg/l) in groups 2, 3 and 4 was associated with higher risk of complications 30 days post-procedure.

Relation of minor cardiac troponin I elevation to late cardiac events after uncomplicated elective successful percutaneous transluminal coronary angioplasty for angina pectoris

There is little information about the relation between mild cardiac troponin I (cTn-I) increase after coronary interventions and late outcome. We therefore focused on the long-term outcome and the clinical, morphologic, and procedural correlates of elevation of cTn-I compared with cardiac troponin T, creatine kinase (CK), CK-MB activity and mass, and myoglobin in 105 patients with successful elective percutaneous transluminal coronary angioplasty (PTCA) for stable or unstable angina. Patients with myocardial infarction and those with unstable angina who had a detectable increase in serum markers before PTCA were excluded. Markers were measured before and after the procedure and for 2 days. Patients were followed up to record recurrent angina, myocardial infarction, cardiac death, repeat PTCA, or elective coronary artery bypass graft surgery. Procedure success was achieved in all cases. Elevation in cTn-I (> or =0.1 microg/L) was observed in 23 of 105 patients (22%) (median peak: 0.25 microg/L); 18% had cardiac troponin T (cTn-T) release (> or = 0.1 microg/L, median peak 0.21); 11.4% CK-MB mass (> or =5 microg/L), and 7.6% myoglobin (> or =90 microg/L) release. Five and 2 patients had elevated CK and CK-MB activity, respectively. Fourteen of 18 patients with cTn-T elevation had a corresponding elevation in cTn-I (kappa 0.68; p = 0.001). Patients positive for cTn-I had more unstable angina (p = 0.042) and heparin before PTCA (p = 0.046), and had longest total time (p = 0.004) and single inflation (p = 0.01). By multivariate logistic regression, predictors of postprocedure cTnI elevation were maximum time of each inflation (odds ratio 9.2; p = 0.0012), type B lesions (odds ratio 6.6; p = 0.013), unstable angina (p = 0.041), and age > or =60 years (p = 0.032). Clinical follow-up was available in 103 patients (98%) (mean 19+/-10 months). Kaplan-Meier survival analysis showed that cTn-I elevation was not an important correlate of cardiac events (p = 0.34, by log-rank analysis). The incidence of recurrent angina, myocardial infarction, cardiac death, and repeat revascularization after 12 months was not different in patients positive or negative for cTn-I. We conclude that cTn-I elevation after successful PTCA is not associated with significantly worse late clinical outcome. Levels of cTn-I allow a much higher diagnostic accuracy in detecting minor myocardial injury after PTCA compared with other markers, but there is no association with periprocedural myocardial cell injury and late outcome when cTn-I and other markers are considered.

Release of cardiac troponin in acute coronary syndromes: ischemia or necrosis?

Analysis of cardiac troponin T and I have been shown to be effective in detecting minor myocardial injury in cardiac patients who present with acute coronary syndromes (ACS). Determination of minor myocardial injury is significant, as these patients have a higher short-term morbidity and mortality than other unstable angina patients with normal concentrations for these markers. In this report, two theories are given as to why cardiac troponin is superior to other markers such as CK-MB for risk stratification. The 'low cut-off concentration model' is based on the fact that troponin is not increased in patients with skeletal muscle disease or injury, resulting in low baseline concentrations of the cardiac isoforms in the absence of active cardiac disease. This enables the use of low decision limits. Troponin also has a higher myocardial tissue content relative to CK-MB, thereby also increasing its clinical sensitivity to irreversible injury. In the 'reversible ischemia model', cytoplasmic free troponin T and I leak across the membrane of myocytes as the result of reduced coronary blood flow. Jeopardized myocardial tissue can recover with acute recanalization. Support for this model comes from clinical observations and animal studies.

The relationship between periprocedural myocardial infarction and subsequent target vessel revascularization following percutaneous coronary revascularization: insights from the EPIC trial. Evaluation of IIb/IIIa platelet receptor antagonist 7E3 in Preventing Ischemic Complications

OBJECTIVES

We sought to determine whether periprocedural myocardial infarction complicating percutaneous coronary revascularization is associated with subsequent clinical restenosis, as judged by the need for target vessel revascularization.

BACKGROUND

Although myocardial enzyme elevation following angioplasty is associated with increased late mortality, its effect on subsequent clinical restenosis, as assessed by the need for late target vessel revascularization (TVR), is unknown.

METHODS

Serial myocardial enzyme determinations were performed on 2,099 patients who underwent angioplasty or atherectomy in the Evaluation of IIb/IIIa platelet receptor antagonist 7E3 in Preventing Ischemic Complications (EPIC) trial. Thirty-day survivors were prospectively followed for three years for adverse clinical events including death and need for TVR.

RESULTS

Within the study population, periprocedural creatine kinase (CK) elevation was a predictor of late mortality. Among patients with elevated CK, however, a paradoxical decrease in the need for late TVR was present. This relationship became progressively more profound as the magnitude of CK release increased. Late TVR occurred in 29.8% of patients with no CK elevation, 24.8% with CK elevation to >3 times normal, and 16.9% with >10 times elevation (hazard ratio 0.51, 95% CI 0.29, 0.91).

CONCLUSIONS

In the EPIC study, patients with periprocedural MI were less likely to develop clinical restenosis as measured by the need for TVR. Mechanistically, although it is unlikely that CK elevation prevents vascular renarrowing per se, myocardial necrosis impairs the clinical manifestation of restenosis, thereby reducing the need for ischemia-driven TVR. This novel finding 1) highlights the potential discordance between angiographic and clinical measures of restenosis, and 2) has implications for clinical trials, as therapies that reduce periprocedural MI may be associated with a perceived excess of restenosis when measured by the need for TVR.