Electrocardiograph changes, troponin levels and cardiac complications after orthopaedic surgery.

INTRODUCTION: The relationship between electrocardiograph (ECG) changes and troponin levels after the emergency orthopaedic surgery are not well characterised. The aim of this study was to determine the correlation between ECG changes (ischaemia or arrhythmia), troponin elevations perioperatively and cardiac complications. MATERIALS AND METHODS: One hundred and eighty-seven orthopaedic patients over 60 years of age were prospectively tested for troponin I and ECGs were performed on the fi rst 3 postoperative mornings or until discharge. RESULTS: The incidences of pre- and postoperative troponin elevation were 15.5% and 37.4% respectively, the majority were asymptomatically detected. Most of the patients who sustained a troponin rise did not have any concomitant ECG changes (51/70 or 72.9%). Postoperative ECG changes were noted in 18.4% (34/185) and of those with ECG changes, slightly more than half (55.9%) had a troponin elevation. Most ECG changes occurred on postoperative day 1 and were non-ST elevation in type. ECG changes occurred more frequently with higher troponin levels. Postoperative troponin elevation (P = 0.018) and not preoperative troponin level (P = 0.060) was associated with ECG changes on univariate analysis. Two premorbid factors were predictors of postoperative ECG changes using multivariate logistical regression; age [odds ratio (OR), 1.05; 95% CI, 1.005 to 1.100, P = 0.029) and sex OR, 2.4; 95% CI, 1.069 to 5.446, P = 0.034). Twenty patients sustained postoperative cardiac complications; 9 (45%) were associated with ECG changes and 16 (80%) with postoperative troponin elevation. Pre- or postoperative troponin elevation better predicted cardiac complications compared with preoperative ECG changes. CONCLUSION: Electrocardiograph changes do not necessarily accompany troponin elevations after the emergency orthopaedic surgery but are more likely to have higher troponin levels. The best predictor of postoperative cardiac complications is troponin elevation.

Does cardiology intervention improve mortality for post-operative troponin elevations after emergency orthopaedic-geriatric surgery? A randomised controlled study.

OBJECTIVES: Troponin elevations are common after emergency orthopaedic surgery and confer a higher mortality at one year. The objective was to determine if comprehensive cardiology care after emergency orthopaedic surgery reduces mortality at one year in patients who sustain a post-operative troponin elevation versus standard care. METHODS: A randomised controlled trial was conducted at a metropolitan teaching hospital in Melbourne, Australia. 187 consecutive patients were eligible with 70 patients randomised. Troponin I was tested peri-operatively and patients with a troponin elevation were randomised to cardiology care versus standard ward management. The main outcome measure was one year mortality. RESULTS: The incidence of a post-operative troponin elevation was 37.4% (70/187) and these 70 patients were randomised. In-hospital cardiac complications were similar between the randomised groups: standard care (7/35 or 20.0%) versus cardiology care (8/35 or 22.9%). There was no difference in 1 year mortality between the randomised groups (6/35 or 17.1% in each group). Multivariate predictors of 1 year mortality were post-operative troponin elevation OR 4.3 (95% CI, 1.1-16.4, p=0.035), age OR 1.1 (95% CI, 1.02-1.2, p=0.016) and number of comorbidities OR 2.1 (95% CI, 1.3-3.5, p=0.004). At 1 year 35/187 (18.7%) sustained a cardiac complication and 23/35 (65.7%) had a troponin elevation. CONCLUSIONS: There was no difference in mortality between patients with a post-operative troponin elevation randomised to cardiology care compared with standard care. Troponin elevation predicted one year mortality. Further research is needed to find an effective intervention to reduce mortality.

N-terminal pro-brain natriuretic peptide and angiotensin-converting enzyme-2 levels and their association with postoperative cardiac complications after emergency orthopedic surgery.

The prognostic usefulness of the cardiac biomarkers N-terminal pro-brain natriuretic peptide (NT-proBNP) and angiotensin-converting enzyme 2 (ACE-2), in predicting adverse cardiac outcomes after orthopedic surgery is not well studied. The aim of our study was to determine the usefulness of perioperative NT-proBNP and ACE-2 for predicting cardiac events after emergency orthopedic surgery. The perioperative NT-proBNP and ACE-2 levels were determined in 187 consecutive patients aged >60 years who underwent orthopedic surgery with 1 year of follow-up for any cardiac complications (defined as acute myocardial infarction, congestive cardiac failure, atrial fibrillation, or major arrhythmia) and death. Of the 187 patients, 20 (10.7%) sustained an in-hospital postoperative cardiac complication. The total all-cause in-hospital and 1-year mortality rate was 1.6% (3 of 187) and 8.6% (16 of 187), respectively. The median preoperative and postoperative NT-proBNP level was greater in patients who sustained an in-hospital cardiac event than in those who had not (386 vs 2,273 pg/ml, p <0.001, and 605 vs 4,316 pg/ml, p <0.001, respectively). Similarly, the postoperative median ACE-2 levels were significantly greater in the patients with an in-hospital cardiac event than in those without (25.3 vs 39.5 pmol/ml/min, p = 0.012). A preoperative NT-proBNP level of ≥741 pg/ml (odds ratio 4.5, 95% confidence interval 1.3 to 15.2, p = 0.017), postoperative troponin elevation (odds ratio 4.9, 95% confidence interval 1.3 to 18.9, p = 0.022), and number of co-morbidities (odds ratio 1.8, 95% confidence interval 1.2 to 2.8, p = 0.009) independently predicted in-hospital cardiac complications on multivariate analysis. The pre- and postoperative NT-proBNP level independently predicted 1-year cardiovascular complications but not the ACE-2 levels. In conclusion, elevated perioperative NT-proBNP predicted in-hospital and 1-year cardiac events in an emergency orthopedic population but the ACE-2 levels did not, which requires additional study for validation.

Usefulness of N-terminal pro-brain natriuretic peptide to predict postoperative cardiac complications and long-term mortality after emergency lower limb orthopedic surgery.

After emergency orthopedic-geriatric surgery, cardiac complications are an important cause of morbidity and mortality. The utility of N-terminal pro-brain natriuretic peptide (NT-pro-BNP) for the prediction of cardiac complications and mortality was evaluated. NT-pro-BNP was tested pre- and postoperatively in 89 patients >60 years of age. They were followed for 2 years for cardiac complications (defined as acute myocardial infarction, congestive cardiac failure, atrial fibrillation or major arrhythmia) or death. Receiver operating characteristic curves were constructed to determine the optimal discriminatory level for cardiac events and death using NT-pro-BNP. Twenty-three patients (25.8%) sustained an in-hospital postoperative cardiac complication. Total all-cause mortality was 3 of 89 (3.4%) in hospital, 21 of 89 (23.6%) at 1 year, and 27 of 89 (30.3%) at 2 years. Median preoperative and postoperative NT-pro-BNP levels were higher in patients who had an in-hospital cardiac event compared to those without (387 vs 1,969 pg/ml, p <0.001; and 676 vs 7,052 pg/ml, p <0.001 respectively). The optimal discriminatory level for preoperative NT-pro-BNP was 842 pg/ml and that for postoperative NT-pro-BNP was 1,401 pg/ml for the prediction of in-hospital cardiac events and 1- and 2-year mortality. Preoperative NT-pro-BNP >/=842 pg/ml (odds ratio 11.6, 95% confidence interval 2.1 to 65.0, p = 0.005) was an independent predictor of in-hospital cardiac complications using multivariate analysis and pre- and postoperative NT-pro-BNP levels were independent predictors of 2-year cardiovascular events. Patients who had preoperative NT-pro-BNP >/=842 pg/ml or postoperative NT-pro-BNP >/=1,401 pg/ml had significantly worse survival using log-rank testing (p <0.001) and these variables independently predicted 2-year mortality. In conclusion, increase pre- and postoperative NT-pro-BNP levels are independent predictors of in-hospital cardiac events and 1- and 2-year mortality in older patients undergoing emergency orthopedic surgery.

Troponin I and NT-proBNP (N-terminal pro-brain natriuretic peptide) do not predict 6-month mortality in frail older patients undergoing orthopedic surgery.

OBJECTIVES: To determine if troponin I and NT-proBNP were predictors of 6-month mortality after emergency orthopedic-geriatric surgery in a frail population. DESIGN: Prospective observational study. SETTING: Orthopedic-geriatric unit of a metropolitan hospital in Australia. PARTICIPANTS: A total of 383 patients were screened; 44 were eligible for this study of which 33 patients consented who were receiving high-level care or had severe dementia or an illness with a prognosis of less than 12 months. MEASUREMENTS: Troponin I and NT-proBNP were tested on one preoperative sample and at least one postoperative blood sample. Cardiac events were defined as acute myocardial infarction, congestive cardiac failure, new onset or rapid atrial fibrillation, major arrhythmia, or cardiac arrest. RESULTS: The mean age of the patients was 85.8 +/- 9.6 years and 93.9% had a fractured neck of femur. Premorbid cardiac conditions were common (24.2% had ischemic heart disease and 21.2% congestive cardiac failure). A third of patients had a preoperative troponin elevation and 60.6% had a postoperative elevation. The mortality within 30 days of surgery was 15.2% (5/33 patients), rising to 39.4% (13/33) at 6 months with 46.2% (6/13) dying of a cardiac cause. The Kaplan-Meier survival curve was not significantly different between patients with and without a troponin elevation. A third of patients sustained a cardiac event at 6 months. The median preoperative NT-proBNP was 1651.50 pg/L, range 25 to 31,227, and median postoperative NT-proBNP was 3038.50pg/L, range 44 to 27,348. Troponin I and NT pro-BNP did not predict 6-month mortality or cardiac complications. Predictors of 6-month mortality using univariate analysis were number of comorbidities OR 2.0 (95% CI 1.1-3.8, P = .033) and premorbid atrial fibrillation OR 7.7 (95% CI 1.2-47.8, P = .028). CONCLUSION: Troponin I and NT-proBNP were not predictors of 6-month mortality or cardiac events in an older frailer population of patients undergoing orthopedic surgery. These patients sustained substantial cardiac morbidity and mortality at 6 months after surgery. The control of symptoms, rather than prolongation of life with cardiological intervention, may be more appropriate for this patient group.

Incidence of post-operative troponin I rises and 1-year mortality after emergency orthopaedic surgery in older patients.

OBJECTIVES: to determine the incidence of post-operative troponin I rises and its association with 1-year all-cause mortality and cardiac events after emergency orthopaedic-geriatric surgery, which has not been studied before. METHODS: one hundred and two patients over the age of 60 were recruited and followed up at 1 year. All consented to serial troponin I measurements peri-operatively. RESULTS: the incidence of a troponin I rise post-operatively was 52.9%. Post-operative acute myocardial infarction was diagnosed in 9.8% and at 1 year, 70% of these patients were dead. At 1 year, 32.4% (33/102) had sustained a cardiac event (myocardial infarction, congestive cardiac failure, atrial fibrillation or major arrhythmia) and using multivariate analysis, post-operative troponin rise (OR 3.9, 95% CI 1.4-10.7, P = 0.008) was an independent predictor of this. Half of the patients with a troponin rise had a cardiac event compared to 18.8% without a rise. All-cause mortality was 20.6% at 1 year; 37% with an associated post-operative troponin rise died versus 2.1% without a rise (P < 0.0001). Using multivariate analysis, only two factors were associated with 1-year all-cause mortality: post-operative troponin rise (OR 12.0, 95% CI 1.4-104.8, P = 0.025) and sustaining a post-operative in-hospital cardiac event (OR 6.6, 95% CI 1.7-25.6, P = 0.006). Furthermore, patients with higher troponin levels had significantly worse survival. CONCLUSIONS: there is a high incidence of post-operative troponin I rises in older patients undergoing emergency orthopaedic surgery with 1-year mortality and cardiac events being significantly increased in these patients. Future studies are needed to determine whether any intervention can improve outcome for these patients.