Troponin elevation pattern and subsequent cardiac and non-cardiac outcomes: Implementing the Fourth Universal Definition of Myocardial Infarction and high-sensitivity troponin at a population level

Could Computed Tomography Coronary Angiography Replace Invasive Coronary Angiography as a First-Line Diagnostic Investigation in Suspected Acute Coronary Syndromes? A Decision-Analytic Model

BACKGROUND

The implementation of high-sensitivity cardiac troponin (hs-cTn) assays into clinical practice has resulted in the identification of a novel cohort of patients with modestly increased troponin concentrations. Subsequent increases in rates of coronary angiography have been observed, without significant increases in rates of coronary revascularisation. Computed tomography coronary angiography (CTCA) is a non-invasive investigation that offers the opportunity to decouple investigation from the impetus to revascularise, and may provide an alternative, more risk-appropriate initial investigative strategy for the cohort with low to moderate hs-cTn increases. This analysis seeks to define the threshold of pre-test probability of coronary revascularisation in patients with suspected acute coronary syndrome at which a strategy of initial CTCA is safe and a more cost-effective approach than standard invasive coronary angiography (ICA).

METHODS

A cost-benefit evaluation was conducted using a decision-analytic model. The primary outcome measure was the incremental cost-effectiveness ratio (ICER) of CTCA in comparison with ICA as an initial diagnostic investigation for patients with hs-cTnT levels between 5 and 100 ng/L. Secondary outcome measures of costs, patient outcomes, and quality-adjusted life years were analysed.

RESULTS

Median base case ICER over 1,000 trials was $17,163 AUD but demonstrated large variability. Sensitivity analysis demonstrated that CTCA was cost-effective until the probability of requiring revascularisation was ∼60%, beyond which point CTCA was associated with higher costs and poorer outcomes than ICA.

CONCLUSIONS

Computed tomography coronary angiography may be a cost-effective first-line investigation for patients with moderate hs-cTnT rises until/up to a 60% pre-test probability for receiving coronary revascularisation. To objectively assess the optimal circumstances of cost-effectiveness, prospective evaluation incorporating the estimated probability of revascularisation will be required.

Comparison of Prognostic Value of 10 Biochemical Indices at Admission for Prediction Postoperative Myocardial Injury and Hospital Mortality in Patients with Osteoporotic Hip Fracture

Aim: To evaluate the prognostic impact at admission of 10 biochemical indices for prediction postoperative myocardial injury (PMI) and/or hospital death in hip fracture (HF) patients. Methods: In 1273 consecutive patients with HF (mean age 82.9 ± 8.7 years, 73.5% women), clinical and laboratory parameters were collected prospectively, and outcomes were recorded. Multiple logistic regression and receiver-operating characteristic analyses (the area under the curve, AUC) were preformed, the number needed to predict (NNP) outcome was calculated. Results: Age ≥ 80 years and IHD were the most prominent clinical factors associated with both PMI (with cardiac troponin I rise) and in-hospital death. PMI occurred in 555 (43.6%) patients and contributed to 80.3% (49/61) of all deaths (mortality rate 8.8% vs. 1.9% in non-PMI patients). The most accurate biochemical predictive markers were parathyroid hormone > 6.8 pmol/L, urea > 7.5 mmol/L, 25(OH)vitamin D < 25 nmol/L, albumin < 33 g/L, and ratios gamma-glutamyl transferase (GGT) to alanine aminotransferase > 2.5, urea/albumin ≥ 2.0 and GGT/albumin ≥ 7.0; the AUC for developing PMI ranged between 0.782 and 0.742 (NNP: 1.84−2.13), the AUC for fatal outcome ranged from 0.803 to 0.722, (NNP: 3.77−9.52). Conclusions: In HF patients, easily accessible biochemical indices at admission substantially improve prediction of hospital outcomes, especially in the aged >80 years with IHD.