Elevated Troponin T Research Articles

Optical Frequency Domain Imaging to Reveal an Angiographically Inapparent Very Late Stent Thrombosis as the Cause of an Acute Coronary Syndrome

![Figure][1] A 60-year-old male was admitted to our hospital with typical angina pectoris at rest and troponin-T elevation, and without significant electrocardiogram changes. The patient had undergone everolimus-eluting stent implantation in the circumflex and left anterior descending artery

Clinical Significance of High Troponin T with Normal Creatine Kinase Levels on Ventricular Function in Acute Coronary Syndromes

Background The role of elevated troponins to predict changes on ventricular function in patients with high creatine kinase (CK) levels has been well established; yet, little is known about the clinical significance of high troponin levels with normal CK levels. Objectives To analyze the relation between Troponin T (TnT) levels and global and regional left ventricular function in patients with acute coronary syndromes (ACS) with normal CK and CK-MB levels. Material and Methods We included patients admitted to the coronary care unit due to ACS within 48 hours from symptoms onset with elevated TnT levels measured by quantitative determination and normal CK and CK-MB levels. Biomarkers were measured at baseline, 24 and 48 hours. Left ventricular function was analyzed by two-dimensional echocardiography at admission and before discharge, and compared with the highest levels of the biomarkers. Ejection fraction, regional wall motion and global systolic longitudinal strain based on speckle-tracking technique were evaluated. Results Thirty patients with ACS were included. The highest median value of TnT was 0.13 m Conclusions High TnT values in ACS with normal CK levels do not modify global or regional left ventricular function assessed by conventional echocardiography. The evaluation of systolic strain using a more sensitive technique detects transient abnormalities. These findings might question the definition of acute myocardial infarction based on high troponin levels, considering that the classical definition is based on elevated CK values which are associated with changes in ventricular function. g/L (interquartile range, 0.07-0.25) measured 24 hours after admission. Left ventricular ejection fraction was 62.9%±10% at admission and 62.8%±10.3% before discharge. Wall motion index was 1.04±0.1 and 1.03±0.1, respectively. Systolic strain at admission was 14.93±3 and improved before discharge 16.51±3.33 (p = 0.0003).

Abstract P009: The Association of Liver Enzymes with Subclinical Myocardial Damage

Background: Nonalcoholic fatty liver disease (NAFLD) is present in up to 30% of the US population and is strongly associated with obesity and diabetes. While a number of studies support an association between NAFLD and cardiovascular disease, limited evidence exists for the association with subclinical myocardial injury. Objective: To test the hypothesis that elevated liver enzymes (Alanine aminotrasferase [ALT], Aspartate aminotranferase [AST] and Gamma-glutamyl transpeptidase [GGT]) in the absence of significant alcohol consumption are independently associated with subclinical myocardial injury, defined by elevated cardiac troponin-T measured using a highly-sensitive assay (hs-cTnT). Methods: We conducted a cross-sectional analysis of 9351 participants from the Atherosclerosis Risk in the Communities (ARIC) Study with information on ALT, AST and GGT , hs-cTnT, and no evidence of coronary heart disease or elevated alcohol consumption (>14 and >21 drinks/week for women and men, respectively). We used logistic regression models to examine the association between liver enzymes and elevated hs-TnT (hs-TnT >0.014 μ g/L ) defined in a healthy reference population. Our secondary outcome was detectable hs-TnT (>0.003 μ g/L ). Results: In this community-based population (mean age 63 years, 60% women, 78% white), 7.2% and 66.1% had elevated and detectable hs-TnT, respectively. Medians [range] of ALT, AST and GGT were 13 [1-381], 18 [5-358] and 21 [2-1277], respectively. Higher levels of ALT, AST and GGT, even within the normal range, were independently associated with elevated hs-TnT (Figure). ALT and AST were also independently associated with detectable hs-TnT. After excluding participants with heart failure, the results remained consistent. Conclusions: In this sample, elevated livers enzymes were independently associated with subclinical myocardial damage suggesting that NAFLD may contribute to myocardial injury beyond its effects on development of clinical atherosclerotic coronary disease.

Abstract P362: Prognostic Value of Troponin in Myocardial Infarction in the Community

Troponin is the biomarker of choice for the diagnosis of myocardial infarction (MI) in clinical practice. Data on its value to predict death, while documented in clinical trials, are lacking from community studies. There is little information from population studies of MI on short and long term predictive value of Troponin on death and nonfatal endpoints such as recurrent ischemic events and heart failure. Methods: We evaluated the prognostic value of Troponin T (TnT) among consecutive persons with incident MI in Olmsted County, MN. Results: 1220 persons (mean age 69±15 years, 45% women) experienced an incident MI (20% ST elevation MI) in Olmsted County, MN between 2002 and 2008. Peak TnT value measured at a median of 1 day post-MI was 1.88±4.19 ng/mL (median 0.52 (25%: 0.16, 75%: 1.75)). After 1.27 years of follow-up, 294 deaths occurred, 360 recurrent ischemic events (recurrent MI or hospitalized unstable angina) and 345 episodes of heart failure. Associations between clinical events and TnT tertiles are shown in the table . Conclusions: In the community, the magnitude of TnT elevation is predictive of recurrent ischemic events, heart failure and early death. It is not associated with long-term mortality. Hazard ratio compared to lowest TnT tertile, 95%CI and p value Adjusted for age, sex and comorbidity Outcome All events Events within 30 days Events among 30 day survivors Death TnT tertile 2 TnT tertile 3 p-value 1.02 (0.78-1.33) 1.15 (0.85-1.57) 0.64 0.64 (0.38-1.06) 1.59 (0.98-2.57) 0.004 1.24 (0.90-1.69) 0.93 (0.62-1.38) 0.26 Recurrent ischemic events TnT tertile 2 TnT tertile 3 p-value 1.45 (1.12-1.88) 1.70 (1.29-2.24) <0.001 1.45 (0.96-2.19) 2.07 (1.37-3.12) 0.002 1.46 (1.05-2.04) 1.45 (1.00-2.10) 0.049 Heart failure TnT tertile 2 TnT tertile 3 p-value 1.03 (0.78-1.36) 2.10 (1.58-2.78) <0.001 0.94 (0.68-1.29) 2.10 1.54-2.87) <0.001 1.38 (0.79-2.41) 2.19 (1.14-4.21) 0.067

Cardiac troponin-T and the prediction of acute and long-term mortality after acute pulmonary embolism

BackgroundAlthough cardiac troponin elevation during acute pulmonary embolism (PE) predicts in-hospital death, its long-term prognostic significance, and the role of troponin-T concentration in this prediction, is unknown. Moreover, its use in acute PE in elderly populations with multiple comorbidities is not well described. MethodsConsecutive patients presenting with confirmed PE to a tertiary hospital between 2000 and 2007 with troponin-T measured were identified retrospectively and their outcomes tracked from a state-wide death registry. ResultsThere were 577 patients, (47% male) with a mean age (±standard deviation) of 70.1±15.2years, of whom 19 died during index admission. Of the 558 patients who survived to discharge, 186 patients died during a mean follow-up of 3.8±2.4years. There were 187 (32%) patients with elevated troponin-T (≥0.01μg/L). Troponin-T concentration was significantly and independently associated with in-hospital and long-term mortality whether analyzed as a continuous or categorical variable (p<0.001). However, different cut-points were required to optimally predict in-hospital and post-discharge long-term mortality in multivariate analysis. Troponin-T≥0.01μg/L was not an independent predictor of in-hospital or post-discharge survival. A cut-point of troponin-T≥0.03μg/L was required to independently predict in-hospital death (p=0.03), and troponin-T≥0.1μg/L was required to independently predict long-term mortality (hazard ratio 2.3, 95% confidence interval 1.4–3.8, p=0.001). ConclusionsTroponin-T elevation during acute PE shows a concentration-dependent relationship with acute and long-term outcome. Concentrations of troponin-T well above the threshold for detection may be required to independently contribute to prediction of outcome in elderly populations with acute PE.

Evaluation of Troponin T Criteria for Periprocedural Myocardial Infarction in Patients With Acute Coronary Syndromes

In patients with acute coronary syndromes undergoing percutaneous coronary intervention (PCI), the diagnosis of periprocedural myocardial infarction is often problematic when the pre-PCI levels of cardiac troponin T (TnT) are elevated. Thus, we examined different TnT criteria for periprocedural myocardial infarction when the pre-PCI TnT levels were elevated and also the associations between the post-PCI cardiac marker levels and outcomes. We established the relation between the post-PCI creatine kinase-MB (CKMB) and TnT levels in 582 patients (315 with acute coronary syndromes and 272 with stable coronary heart disease). A post-PCI increase in the CKMB levels to 14.7 μg/L (3 × the upper reference limit [URL] in men) corresponded to a TnT of 0.23 μg/L. In the 85 patients with acute coronary syndromes and normal CKMB, but elevated post peak TnT levels before PCI (performed at a median of 5 days, interquartile range 3 to 7), the post-PCI cardiac marker increases were as follows: 21 (24.7%) with a ≥ 20% increase in TnT, 10 (11.8%) with an CKMB level >3 × URL, and 12 (14%) with an absolute TnT increase of >0.09 μg/L (p <0.005 for both). In the patients with stable coronary heart disease and post-PCI cardiac markers > 3× URL compared to those without markers elevations, the rate of freedom from death or nonfatal myocardial infarction was 88% for those with TnT elevations versus 99% (p <0.001, log-rank) and 84% for those with CKMB elevations versus 98% (p <0.001, log-rank). Of the patients with acute coronary syndromes, the post-PCI marker levels did not influence the outcomes. In conclusion, in patients with acute coronary syndromes and elevated TnT levels undergoing PCI several days later, ≥20% increases in TnT were more common than absolute increments in the TnT or CKMB levels of >3× URL. Also, periprocedural cardiac marker elevations in patients with acute coronary syndromes did not have prognostic significance.

Intense Yellow Culprit Plaque Coloration is Closely Associated with Troponin-T Elevation and Flow Complications Following Elective Coronary Stenting

The elevation of troponin-T (TnT) and occurrence of transient slow-flow phenomena have been recognized as procedure-related myocardial injuries. Little is known about the characteristics of high-risk plaque resulting in myocardial injury after coronary stenting. The culprit plaques in 42 consecutive patients with stable angina undergoing elective coronary stenting were observed by angioscopy. The plaque color upon angioscopic examination was classified as either intense yellow or not yellow. Slow flow was defined as < TIMI grade 3 flow during the procedure. The TnT levels were measured 8, 16, and 24 hours after stenting, and myocardial injury was defined as TnT ≥ 0.03 ng/mL at any time point. Twenty-four patients (57%) had intense yellow plaques and myocardial injury occurred in 22 patients (52%). The frequency of intense yellow plaque was significantly higher in the patients with myocardial injury than in those without myocardial injury (91% vs. 20%, p < 0.001). Transient slow flow occurred frequently in patients with myocardial injury than in those without myocardial injury (23% vs. 0%, p = 0.049). All patients with transient slow flow had intense yellow plaques at the culprit lesions. Intense yellow culprit plaque coloration was closely associated with TnT elevation and flow complications following elective coronary stenting. Angioscopically-observed intense yellow coloration may therefore predict high-risk plaque for peri-procedural myocardial injury.

Resting Echocardiography for the Early Detection of Acute Coronary Syndromes in Chest Pain Unit Patients

The purpose of this study is to assess the ability of resting echocardiography to detect an acute coronary syndrome (ACS) before the occurrence of ischemic electrocardiogram (ECG) changes or troponin-T elevations. Four hundred and three patients who presented to the emergency room (ER) with chest pain, normal ECGs, and normal troponin-T levels were admitted to the cardiologist-run Chest Pain Unit (CPU) for further monitoring. They underwent serial resting echocardiography for monitoring of left ventricle wall motion (LVWM), ECG telemetry monitoring, and serial troponin-T measurements. An ACS was detected in 49 patients (12.1%). These 49 patients were then subdivided into three different groups based on the initial mode of detection of their ACS. In group A, 16 of 49 (32.6%) patients had ACS shown by echocardiographic detection of LVWM abnormalities. In group B, 24 of 49 (48.9%) patients had an ACS detected by ischemic ECG changes. In group C, 9 of 49 (18.3%) patients had an ACS detected by troponin-T elevations. The shortest time interval between CPU-admission and ACS-detection occurred in group A (A vs. B, P < 0.003; A vs. C, P < 0.0001). In group A, cardiac angiogram showed that the culprit coronary lesion was more frequent in the circumflex artery (11 out of 16; 68.7%) (LCx vs. LAD, P < 0.02; LCx vs. RCA, P < 0.001) and of these 11 patients with circumflex lesions, the ECG was normal in eight (72.7%) patients. This study demonstrates the utility of LVWM monitoring by serial echocardiography as part of a diagnostic protocol that can be implemented in a CPU. Furthermore, echocardiography could become an essential tool used in the diagnosis of ACS secondary to circumflex lesions.

Mortality in Patients Undergoing Open Aortoiliac Surgery: Prognostic Value of Troponin T in the Immediate Postoperative Period

Patients undergoing open aortoiliac surgery constitute a high-risk subgroup. The aim of this study was to evaluate the relationship between postoperative troponin T (TnT) elevation with the associated postoperative mortality, and mean hospital stay. This was a prospective observational study of consecutive patients who underwent open aortoiliac surgery during 2006. TnT levels in the first 72 hours after the operation, immediate mortality, postoperative care unit stay, and total postoperative hospital stay were recorded. Statistical analyses were performed with the program SPSS 14.0; the chi-square test (or the Fisher's exact test) was used for qualitative variables and the Mann-Whitney test for quantitative variables. Of the 65 patients included in the study, postoperative TnT was elevated in 14 (21.5%) patients. No significant differences were found in age, sex, hypertension, dyslipidemia, smoking, diabetes mellitus, ischemic heart disease, heart failure, bronchopathy, or renal failure between groups. Mortality in patients with elevated TnT levels was significantly higher (42% compared with 3.92%; relative risk 10.93 +/- 0.76; p = 0.001). Likewise, their mean postoperative intensive care unit stay was significantly greater (23.21 +/- 6.96 days compared to 2.86 +/- 1.96; p < 0.001). This finding resulted in a significantly longer postoperative hospital stay (32.57 +/- 25.38 days compared with 12.47 +/- 2.21). TnT level in the immediate postoperative period is a highly relevant indicator of prognosis in patients undergoing major vascular surgery.

Prognostic value of stable troponin T elevation in patients discharged from emergency department

Troponin elevation in the absence of myocardial infarction is a challenging diagnostic problem in the emergency department (ED). Elevated troponin levels have a short-term negative prognostic value in critically ill patients hospitalized for all causes. No data are available about the short-term prognostic value of elevated troponin in ED patients discharged from hospital without clinical evidence of acute diseases. The aim of the study was to evaluate the short-term prognostic value of elevated stable troponin T (TnT) in ED patients discharged from hospital. Two hundred and thirty-two consecutive adult individuals admitted to ED evaluation for all causes, with TnT test and without evidence of acute diseases requiring hospitalization, were evaluated. The patients with TnT positive tests, without dynamic changes during in-hospital observation and discharged from hospital, were considered as case patients. For each case patient enrolled, the consecutive patient of the same sex and similar age, admitted to the ED on the same day and discharged with normal plasma TnT values, was enrolled as her/his control. The incidence of adverse clinical events in both cases and controls assessed by a phone call at 24 h, 7 days and 30 days after the ED discharge was recorded. Ninety-four cases and 94 controls were finally considered. The 30-day adverse events (death, hospitalization and ED access) were 35 of the 94 (37.2%) in cases and 18 of the 94 (19.1%) in controls (P < 0.01). The patients discharged from ED with stable elevated TnT levels, but without acute diseases, had a short-term prognosis worse than that of patients with similar clinical presentation but with normal TnT values.

Aspirin resistance determined from a bed-side test in patients suspected to have acute coronary syndrome portends a worse 6 months outcome

Coronary patients resistant to aspirin may have increased risk for ischemic events. Little data were available for patients presenting acutely with chest pain. We used the VerifyNow Aspirin to determine aspirin responsiveness of 314 patients regularly taking aspirin 75-300 mg daily for >or=4 weeks who presented with suspected acute coronary syndrome in Emergency Department. Aspirin resistance was defined as an aspirin reaction unit (ARU) >or=550, and the clinical team was blinded to the ARU reading. The pre-specified study endpoints were the diagnosis of acute myocardial infarction (AMI) for the index admission and major adverse cardiac events including cardiovascular death or recurrent acute coronary syndrome requiring hospitalization within 6 months. Aspirin resistance was noted in 30 (9.6%) patients. There was no difference in the diagnosis of AMI for the index presentation (3/30, 10% vs. 25/284, 8.8%, P = 0.91). Among the 312 hospital survivors, aspirin resistant patients had increased adverse events over 6 months with an overall hazard ratio of 10.0 [95% confidence interval (CI) 4.6-22.0]. After adjusted for elevated Troponin-T, the only confounder in the model, the hazard ratio was 11.1 (95% CI 4.7-26.0). Results were similar in patients treated only medically without revascularization (adjusted hazard ratio 12.1, 95% CI 4.7-26.4). The increased events were observed both from discharge to 30 days and from 30 days to 6 months. Aspirin resistance occurs in approximately 10% of patients presenting with suspected acute coronary syndrome and is associated with adverse cardiac events.

Improved Function and Myocardial Repair of Infarcted Heart by Intracoronary Injection of Mesenchymal Stem Cell-Derived Growth Factors

Transplantation of mesenchymal stem cells (MSC) improves repair and function recovery following myocardial infarction (MI), but underlying mechanisms remain to be elucidated. We hypothesize that MSC could achieve protection by paracrine effects through released mediators rather than direct cardiac regeneration. We sought to characterize the effects of MSC-secreted growth factors on extent of early recovery from MI. Swine subjected to acute MI by temporary balloon occlusion of the left anterior descending coronary artery using percutaneous techniques received intracoronary injection of either concentrated MSC-derived growth factors or control medium. Animals were killed at 7 days to evaluate early effects. Treatment with MSC-derived factors significantly reduced cardiac troponin-T elevation and improved echocardiographic parameters, including fractional area shortening, stroke volume, cardiac output, and wall motion score index. Quantitative evaluation of fibrosis by Verhoff staining revealed a reduction of the fibrotic area in the infarcted zone. Similarly, Masson's trichrome staining revealed reduced myocardial damage as demonstrated by areas of relatively preserved myocardium in the infarcted area. TUNEL assay demonstrated less cardiomyocyte apoptosis. Protein array detected the presence of angiogenic (vascular endothelial growth factor, endothelin, and epiregulin), anti-apoptotic (Galectin-3, Smad-5, sRFP-1, and sRFP-4) and anti-remodeling factors. Reverse transcription polymerase chain reaction confirmed the expression of these factors. In summary, a single intracoronary injection of concentrated biologically active factors secreted by MSC could achieve early protection of ischemic myocardium and improve cardiac repair and contractility. MSC-derived growth factors injection (rather than MSC themselves) should be evaluated as a novel therapy to treat ischemic heart disease, avoiding many practical and technical issues of cell therapy.

Elevated Troponin-T Levels in Patients with Exertional Heat Stroke

Elevated Troponin-T Levels in Patients with Exertional Heat Stroke

Are Electrocardiographic Changes in Patients with Acute Subarachnoid Hemorrhage Associated with Takotsubo Cardiomyopathy?

Background: Subarachnoid hemorrhage (SAH) has been associated with electrocardiographic (ECG) changes, arrhythmias, and release of cardiac enzymes. Recently, Takotsubo cardiomyopathies, presenting typical ECG changes and left ventricular (LV) regional wall-motion abnormalities (RWMAs), have been reported and considered to be a result of high norepinephrine (NE) levels. We hypothesized that ST-T-wave changes in patients with SAH may be manifestations of Takotsubo cardiomyopathy and associated with RWMAs. Methods: We instituted consecutive echocardiographic screening of all patients with acute aneurysmal SAH. A standard 12-lead ECG and blood samples for creatine kinase (CK) MB isoenzyme and troponin-T (Tn-T) were obtained. To evaluate sympathetic nervous activity, we obtained blood samples and urine samples for NE. Results: Of 42 patients with acute aneurysmal SAH, 26 had abnormal ECG including rhythm abnormalities. Ten of 12 patients with ST-T-wave changes had severe neurologic deficits, but 1 patient had RWMAs on echocardiography. Another patient with LV dysfunction showed a normal ST-T wave. In patients with ST-T-wave changes, elevated Tn-T (8.3 vs. 3.3%), CK-MB (8.3 vs. 10.0%), plasma and urine NE (16.7 and 33.3% vs. 16.7 and 50.0%), and mortality (8.3 vs. 13.3%) were not significantly higher. All 5 deaths resulted from noncardiac causes. High plasma and urine NE levels were not related to neurologic severity or mortality. Conclusions: Although ECG abnormalities are frequently seen in SAH patients, the incidence of RWMAs is very low. Electrocardiographic manifestations in patients with SAH and Takotsubo cardiomyopathy are similar, but ECG abnormalities in patients with SAH are mostly not related to LV dysfunction.

Abstract 4865: Detection of Basal and Transient Myocardial Ischemia-Induced Cardiac Troponin Release Into Coronary Circulation by Highly Sensitive Assay

Background: Cardiac troponin is well established as a specific biomarker for cardiomyocyte necrosis in acute coronary syndromes but not in angina pectoris. However, troponin release from coronary circulation during transient ischemic attack by angina remains to be determined because of lower sensitivity of traditional troponin assay. We assessed the basal and angina-induced occurrence of troponin release using highly sensitive troponin T (TnT) assay before and after acetylcholine-induced coronary spasm. Methods and Results: Serum cardiac TnT levels sampled from peripheral vein (PV), aortic root (Ao), and coronary sinus (CS) were measured by highly sensitive assay in 108 consecutive patients (57% men, 67±10 years) suspected of stable coronary artery disease (CAD). TnT in PV was detectable in 91.4% of the patients [9.8 (7.1, 14.7) pg/mL for median (25 th , 75 th percentile)]. At the baseline condition, there was significant increase in TnT levels from Ao [9.6 (6.9, 14.3) pg/mL] to CS [10.9 (7.9, 17.3) pg/mL, p&lt;0.001] in 92.5% of patients and the difference was 1.2 (0.6, 2.5) pg/mL, which reflects basal transcardiac release of TnT. The cardiac release of TnT positively correlated with PV levels (r=0.21, p&lt;0.05). In univariate logistic regression analysis, male gender (odds ratio [OR]; 3.65, 95% confidence interval [CI]; 1.58 – 8.47, p&lt;0.01), presence of heart failure (OR; 3.18, 95% CI; 1.11–9.15, p&lt;0.05), and presence of organic CAD (OR; 2.40, 95% CI; 1.05–5.47, p&lt;0.05) were significantly correlated with elevated transcardiac TnT release (above median). Furthermore, there was significant increase in transcardiac TnT release after acetyocholine provocation test in patients with positive result of coronary spasm [7.2 (−1.8, 11.5) pg/mL, p&lt;0.05] but not in 19 patients with negative result [0.0 (−0.5, 0.5) pg/mL, p=0.95]. Conclusions: Basal TnT release in coronary circulation was observed in most of patients suspected of CAD and the transcardiac TnT values were significantly correlated with the peripheral levels. Presence of heart failure or CAD significantly contributed to the elevated TnT release in stable states. This sensitive assay detected angina like transient myocardial ischemia-induced significant increase in transcardiac troponin release.

Increased Rehospitalization Rate After Coronary Bypass Operation for Acute Coronary Syndrome: A Prospective Study in 200 Patients

Patients with acute coronary syndrome (ACS) run increased risk of cardiac death or myocardial infarction after coronary artery bypass grafting (CABG). Long-term survival is similar in ACS patients and patients with stable angina pectoris. This study analyzed the cardiac rehospitalization rate up to 10 years after CABG for ACS and stable angina. CABG was done in 200 patients, 100 with ACS and 100 with stable angina. Troponin-T levels were assayed and the severity of the unstable symptoms was classified according to Braunwald. Early outcome, long-term survival, and freedom from cardiac rehospitalization were analyzed. Three ACS patients died early and 12 died late. In the control group, there were no early and 19 late deaths. The cumulative long-term survival was 85% for the ACS patients and 81% for the stable patients (p = 0.75). Postoperative myocardial infarction occurred in 5 unstable patients and 1 stable patient (p = 0.01). At 3 years after the operation, freedom from cardiac rehospitalization was significantly higher in the stable patients (9 vs 27, p = 0.001). In the end of the follow-up, there were no differences in the rehospitalization rate. Similar and excellent long-term survival was found in both ACS and stable patients long-term after CABG. In patients with ACS, variables such as elevated troponin-T and angina at rest herald an increased risk of perioperative myocardial infarction. Freedom from cardiac rehospitalization is significantly higher in stable patients compared with ACS patients during the first postoperative years, indicating recurrent ischemia.

Takotsubo Cardiomyopathy in Two Preoperative Patients with Pain

Reversible stress-induced cardiomyopathy, i.e., Takotsubo cardiomyopathy, rarely presents in preoperative patients. We provide the case reports of two patients who presented with Takotsubo cardiomyopathy, which we surmise was due to excess endogenous catecholamine production in response to acute pain. Electrocardiogram revealed T-wave inversion, with peak Troponin-T elevation in each case, i.e., 0.66 microg/L and 0.14 microg/L (normal range <0.03 microg/L). Despite these findings consistent with acute myocardial infarction, neither patient had obstructive coronary disease at angiography. Left ventriculography showed apical ballooning, a typical feature of the Takotsubo syndrome. Ventricular dysfunction had resolved completely at repeat echocardiography 2 wk later, after adequate analgesia and surgery.

Troponin T predicts in-hospital and 1-year mortality in patients with pulmonary embolism

We aimed to determine the prognostic value of troponin T (TNT) for in-hospital and 1-yr mortality in a large sample of patients with pulmonary embolism (PE). Patients presenting at the emergency department of a tertiary care centre from January 1998 to December 2006 with PE were included. A blood sample was taken at the time of presentation. To determine in-hospital and 1-yr mortality, data from the hospital records and the national death register were used. TNT was determined in 563 out of 737 patients with proven PE. TNT was elevated (>0.03 ng x mL(-1)) in 27%. In-hospital survival was 79% in TNT-positive patients compared with 94% in TNT-negative patients (p<0.001). 1-yr survival was 71% in TNT-positive patients compared with 90% in TNT-negative patients (p<0.001). Elevated TNT levels meant a four-times higher risk of in-hospital death and a three-times higher risk of 1-yr mortality, even after adjustment for the other most important risk factors of death in this population. Elevated TNT independently predicts in-hospital and 1-yr mortality in patients with acute PE.

Contribution of Renal Function Impairment to Unexplained Troponin T Elevations in Congestive Heart Failure

Background. Patients with severe congestive heart failure (CHF) often have unexplained elevations in serum concentrations of troponin T (TnT), and it is proposed that this is due to cardiac TnT release because of underlying cardiac disease. We investigated whether impaired renal function is an additional underlying phenomenon contributing to increased TnT levels in patients with CHF. Methods. Sixty-two patients with nonischemic CHF, New York Heart Association (NYHA) class III–IV, with normal coronary angiogram and normal serum creatinine were included in the study. Baseline glomerular filtration rate (GFR) was calculated using the Cockcroft Gault equation. Results. Although mean creatinine level was normal (0.92 ± 0.17 mg/dL), mean GFR was low (56 ± 16 mL/min) in the cohort. Elevated (≥0.02 >g/L) TnT was measured in 33 patients (53%). Compared with patients with normal (<0.02 >g/L) TnT levels, patients with elevated TnT had significantly higher NYHA class (p = 0.02), longer duration of disease (p = 0.02), lower GFR (p = 0.0001), and lower LVEF (p = 0.0001). There were significant associations between TnT levels and duration of disease (r = 0.29, p = 0.01), creatinine (r = 0.30, p = 0.01), GFR (r = −0.55, p < 0.0001), and LVEF (r = −0.39, p = 0.001). Independence of these associations was evaluated in multiple linear regression analysis, and serum TnT was independently and negatively associated only with GFR (p = 0.005). Conclusions. Renal function (GFR) correlated significantly and more strongly than cardiac function (LVEF) with the serum TnT levels in patients with CHF. This supports our hypothesis that impaired renal function causes the accumulation of troponin and is very likely the cause of unexplained elevations of serum TnT in patients severe CHF.

Chronic kidney disease, diabetes mellitus and pulmonary wedge pressure are predictors of elevated cardiac troponinT in non-ischemic chronic heart failure

Chronic kidney disease, diabetes mellitus and pulmonary wedge pressure are predictors of elevated cardiac troponinT in non-ischemic chronic heart failure