Prognostic value of high-sensitivity cardiac troponin I early after coronary artery bypass graft surgery (original) (raw)

High-sensitivity cardiac troponin T in prediction and diagnosis of myocardial infarction and long-term mortality after noncardiac surgery

American Heart Journal, 2013

Background-Perioperative myocardial infarction is a serious complication after non-cardiac surgery. We hypothesized that preoperative cardiac troponin T detected with a novel highsensitivity (hs-cTnT) assay will identify patients at risk of acute myocardial infarction (AMI) and long-term mortality after major non-cardiac surgery. Methods-This was a prospective cohort study within the Vitamins in Nitrous Oxide (VINO) trial (n=608). Patients had been diagnosed with or had multiple risk factors for coronary artery disease and underwent major non-cardiac surgery. Cardiac troponin I (contemporary assay) and troponin T (high-sensitivity assay), and 12-lead electrocardiograms were obtained before and immediately after surgery and on postoperative day 1, 2 and 3. Results-At baseline before surgery, 599 patients (98.5%) had a detectable hs-cTnT concentration and 247 (41%) were above 14 ng/L (99 th percentile). After surgery, 497 patients (82%) had a rise in hs-cTnT (median Δhs-cTnT +2.7 ng/L [IQR 0.7, 6.8]). During the first three postoperative days, 9 patients (2.5%) with a preoperative hs-cTnT <14 ng/L suffered from AMI, compared to 21 patients (8.6%) with a preoperative hs-cTnT >14 ng/L (odds ratio, 3.67; 95% CI 1.65-8.15). During long-term follow-up, 80 deaths occurred. The 3-year mortality rate was 11% in patients with a preoperative hs-cTnT concentration <14 ng/L compared to 25% in patients with a preoperative hs-cTnT >14 ng/L (adjusted hazard ratio, 2.17; 95% CI 1.19-3.96).

Usefulness of postoperative high-sensitive troponin T measurement and implications for defining type 5 infarction

Authorea (Authorea), 2021

Background and aim of the study Guidelines on myocardial revascularization indicate for type V myocardial infarction (MI) that postoperative troponin elevations need not be exclusively ischemic but may also be caused by direct epicardial injury. Additional complexity arises from the introduction of high-sensitive troponin markers. The present study attempts to contribute to the understanding of postoperative high-sensitive cardiac troponin T (hs-cTnT) increase. Methods Type of surgery, potential factors affecting the postoperative hs-cTnT increase, and possible thresholds indicative of type V MI were analyzed. Results Among 400 included patients, 2.8% had intervention-related ischemia analogous to the type V MI definition. Receiver-operating characteristics confirmed good discriminatory power for hs-cTnT and creatine kinase myocardial band (CK-MB), with ischemia indicating thresholds for hs-cTnT (1705.5 ng/l) and for CK-MB (113 U/l). The median postoperative hs-cTnT/CK-MB increase differed significantly depending on the type of surgery, with the highest increase after mitral valve and the lowest after off-pump coronary surgery. Regression analysis confirmed Maze procedure (p<0.001), cardiopulmonary bypass time (p=0.03), emergency indications (p= 0.01) and blood transfusion (p=0.02) as significant factors associated with hs-cTnT increase. In contrast, CK-MB increase was also associated with mortality (p=0.002). Intra-pericardial defibrillation was the only ischemia-independent factor additionally associated with proposed thresholds (p<0.001). Conclusions The present results confirm the influence of the type of surgery and other intervention-related parameters on the postoperative hs-cTnT increase. Type V MI-indicating thresholds may require reassessment, especially using high-sensitive markers.

Using postoperative cardiac Troponin-I (cTi) levels to detect myocardial ischaemia in patients undergoing vascular surgery

2001

Background. Cardiac complications occur commonly in vascular surgery patients. Diagnosis of cardiac complications is difficult because of the inaccuracies associated with traditional cardiac enzyme measurements. CTi, a highly sensitive and specific marker of myocardial injury, may be able to detect cardiac complications with greater ease and accuracy. Methods. The study prospectively examined 100 consecutive patients who underwent major vascular surgery between 6/7/98 and 31/12/98 at the Royal Brisbane Hospital. Daily measurements of cTi, creatine kinase (CK), creatine kinase MB (CKMB), CKMB index, renal function and haemoglobin were taken for three postoperative days. One postoperative electrocardiograph (ECG) was taken. An extensive cardiac history was taken. Intraoperative and postoperative events were recorded. Findings. There were 100 patients. 18 patients (18%) had a cTi elevation. On the basis of classical diagnostic criteria, 15 patients (15%) suffered one or more cardiac complication (either myocardial infarction, congestive cardiac failure, unstable angina or atrial fibrillation). One patient (1%) who had a cTi elevation died. CTi elevation occurred in five patients (5%) who were not diagnosed with cardiac complications based on traditional criteria. Despite not meeting specific diagnostic criteria for cardiac complications, all patients showed signs and symptoms that could be attributed to myocardial ischaemia. Every patient who developed congestive cardiac failure or atrial fibrillation had a cTi elevation. A Chi-square analysis revealed a significant association between cTi elevation and postoperative cardiac complications. Four variables contributed small but significant amounts of unique variance to the prediction of peak cTi on linear regression analysis. These were peak CKMB index, postoperative congestive cardiac failure, postoperative chest pain and postoperative cardiac complications. Conclusions. Routine cTi monitoring of postoperative vascular patients would be an effective and inexpensive way to detect patients with cardiac complications. The relationship between postoperative cTi elevation and significant coronary artery disease remains to be shown.

Serum Cardiac Troponin I after Conventional and Minimal Invasive Coronary Artery Bypass Surgery

Clinical Chemistry and Laboratory Medicine, 2001

We evaluated myocardial release of cardiac troponin I (cTnI) in patients treated with conventional coronary artery bypass grafting (CABG), which employs extracorporeal circulation, and different kinds of minimal invasive coronary artery bypass grafting (MICABG), a surgical technique where the operation is performed without extra-corporeal circulation. Furthermore, we evaluated the usefulness of serum cTnI measurement to detect perioperative myocardial infarction (PMI) after coronary artery bypass surgery. Thirty-one patients were included: sixteen underwent CABG, fifteen underwent different MICABG and five patients had PMI. Blood specimens for cTnI measurements were collected up to 72 hours after opening the graft. Aortic cross-clamping time was a minor determinant of myocardial damage; on the other side, the trauma during surgery correlated with the number of involved arteries and with the manoeuvre employed to obtain heart dislocation, and appeared a more important determinant of myocardial damage. In patients with PMI, the cumulative release of cTnI was higher than in patients free from PMI; however, only after 24-72 hours we observed significant differences in serum cTnI values, because the increased perioperative values of cTnI complicated the interpretation of the myocardial status and a single cutoff could not be used to exclude PMI.

Cardiac Troponin I Predicts Short-Term Mortality in Vascular Surgery Patients * Reply

Circulation, 2003

Background-Cardiac troponin I (cTnI) is a highly sensitive and specific marker for myocardial injury that predicts outcomes in patients with acute coronary syndromes. Cardiovascular complications are the leading cause of morbidity and mortality in patients who have undergone vascular surgery. However, postoperative surveillance with cardiac enzymes is not routinely performed in these patients. We evaluated the association between postoperative cTnI levels and 6-month mortality and perioperative myocardial infarction (MI) after vascular surgery. Methods and Results-Two hundred twenty-nine patients having aortic or infrainguinal vascular surgery or lower extremity amputation were included in this study. Blood samples were analyzed for cTnI immediately after surgery and the mornings of postoperative days 1, 2, and 3. An elevated cTnI was defined as serum concentrations Ͼ1.5 ng/mL in any of the 4 samples. Twenty-eight patients (12%) had postoperative cTnI Ͼ1.5ng/mL, which was associated with a 6-fold increased risk of 6-month mortality (adjusted OR, 5.9; 95% CI, 1.6 to 22.4) and a 27-fold increased risk of MI (OR, 27.1; 95% CI, 5.2 to 142.7). Furthermore, we observed a dose-response relation between cTnI concentration and mortality. Patients with cTnI Ͼ3.0 ng/mL had a significantly greater risk of death compared with patients with levels Յ0.35 ng/mL (OR, 4.9; 95% CI, 1.3 to 19.0). Conclusions-Routine postoperative surveillance for cTnI is useful for identifying patients who have undergone vascular surgery who have an increased risk for short-term mortality and perioperative MI. Further research is needed to determine whether intervention in these patients can improve outcome. (Circulation. 2002;106:2366-2371.)