Is Physiologic Stress Test with Imaging Comparable to Anatomic Examination of Coronary Arteries by Coronary Computed Tomography Angiography to Investigate Coronary Artery Disease? - A Systematic Review and Meta-Analysis

Troponin in acute chest pain to risk stratify and guide effective use of computed tomography coronary angiography (TARGET-CTCA): a randomised controlled trial

BACKGROUND

The majority of patients with suspected acute coronary syndrome presenting to the emergency department will be discharged once myocardial infarction has been ruled out, although a proportion will have unrecognised coronary artery disease. In this setting, high-sensitivity cardiac troponin identifies those at increased risk of future cardiac events. In patients with intermediate cardiac troponin concentrations in whom myocardial infarction has been ruled out, this trial aims to investigate whether outpatient computed tomography coronary angiography (CTCA) reduces subsequent myocardial infarction or cardiac death.

METHODS

TARGET-CTCA is a multicentre prospective randomised open label with blinded endpoint parallel group event driven trial. After myocardial infarction and clear alternative diagnoses have been ruled out, participants with intermediate cardiac troponin concentrations (5 ng/L to 99th centile upper reference limit) will be randomised 1:1 to outpatient CTCA plus standard of care or standard of care alone. The primary endpoint is myocardial infarction or cardiac death. Secondary endpoints include clinical, patient-centred, process and cost-effectiveness. Recruitment of 2270 patients will give 90% power with a two-sided P value of 0.05 to detect a 40% relative risk reduction in the primary endpoint. Follow-up will continue until 97 primary outcome events have been accrued in the standard care arm with an estimated median follow-up of 36 months.

DISCUSSION

This randomised controlled trial will determine whether high-sensitivity cardiac troponin-guided CTCA can improve outcomes and reduce subsequent major adverse cardiac events in patients presenting to the emergency department who do not have myocardial infarction.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03952351. Registered on May 16, 2019.

Early computed tomography coronary angiography in adults presenting with suspected acute coronary syndrome: the RAPID-CTCA RCT

BACKGROUND

Acute coronary syndrome is a common medical emergency. The optimal strategy to investigate patients who are at intermediate risk of acute coronary syndrome has not been fully determined.

OBJECTIVE

To investigate the role of early computed tomography coronary angiography in the investigation and treatment of adults presenting with suspected acute coronary syndrome.

DESIGN

A prospective, multicentre, open, parallel-group randomised controlled trial with blinded end-point adjudication.

SETTING

Thirty-seven hospitals in the UK.

PARTICIPANTS

Adults (aged ≥ 18 years) presenting to the emergency department, acute medicine services or cardiology department with suspected or provisionally diagnosed acute coronary syndrome and at least one of the following: (1) a prior history of coronary artery disease, (2) a cardiac troponin level > 99th centile and (3) an abnormal 12-lead electrocardiogram.

INTERVENTIONS

Early computed tomography coronary angiography in addition to standard care was compared with standard care alone. Participants were followed up for 1 year.

MAIN OUTCOME MEASURE

One-year all-cause death or subsequent type 1 (spontaneous) or type 4b (stent thrombosis) myocardial infarction, measured as the time to such event adjudicated by two cardiologists blinded to the computerised tomography coronary angiography ( CTCA ) arm. Cost-effectiveness was estimated as the lifetime incremental cost per quality-adjusted life-year gained.

RESULTS

Between 23 March 2015 and 27 June 2019, 1748 participants [mean age 62 years (standard deviation 13 years), 64% male, mean Global Registry Of Acute Coronary Events score 115 (standard deviation 35)] were randomised to receive early computed tomography coronary angiography (n = 877) or standard care alone (n = 871). The primary end point occurred in 51 (5.8%) participants randomised to receive computed tomography coronary angiography and 53 (6.1%) participants randomised to receive standard care (adjusted hazard ratio 0.91, 95% confidence interval 0.62 to 1.35; p = 0.65). Computed tomography coronary angiography was associated with a reduced use of invasive coronary angiography (adjusted hazard ratio 0.81, 95% confidence interval 0.72 to 0.92; p = 0.001) but no change in coronary revascularisation (adjusted hazard ratio 1.03, 95% confidence interval 0.87 to 1.21; p = 0.76), acute coronary syndrome therapies (adjusted odds ratio 1.06, 95% confidence interval 0.85 to 1.32; p = 0.63) or preventative therapies on discharge (adjusted odds ratio 1.07, 95% confidence interval 0.87 to 1.32; p = 0.52). Early computed tomography coronary angiography was associated with longer hospitalisations (median increase 0.21 days, 95% confidence interval 0.05 to 0.40 days) and higher mean total health-care costs over 1 year (£561 more per patient) than standard care.

LIMITATIONS

The principal limitation of the trial was the slower than anticipated recruitment, leading to a revised sample size, and the requirement to compromise and accept a larger relative effect size estimate for the trial intervention.

FUTURE WORK

The potential role of computed tomography coronary angiography in selected patients with a low probability of obstructive coronary artery disease (intermediate or mildly elevated level of troponin) or who have limited access to invasive cardiac catheterisation facilities needs further prospective evaluation.

CONCLUSIONS

In patients with suspected or provisionally diagnosed acute coronary syndrome, computed tomography coronary angiography did not alter overall coronary therapeutic interventions or 1-year clinical outcomes, but it did increase the length of hospital stay and health-care costs. These findings do not support the routine use of early computed tomography coronary angiography in intermediate-risk patients with acute chest pain.

TRIAL REGISTRATION

This trial is registered as ISRCTN19102565 and Clinical Trials NCT02284191.

FUNDING

This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 37. See the NIHR Journals Library website for further project information.

Early computed tomography coronary angiography in patients with suspected acute coronary syndrome: randomised controlled trial

OBJECTIVES

To establish if the use of early computed tomography (CT) coronary angiography improves one year clinical outcomes in patients presenting to the emergency department with acute chest pain and at intermediate risk of acute coronary syndrome and subsequent clinical events.

DESIGN

Randomised controlled trial.

SETTING

37 hospitals in the UK.

PARTICIPANTS

Adults with suspected or a provisional diagnosis of acute coronary syndrome and one or more of previous coronary heart disease, raised levels of cardiac troponin, or abnormal electrocardiogram.

INTERVENTIONS

Early CT coronary angiography and standard of care compared with standard of care only.

MAIN OUTCOME MEASURES

Primary endpoint was all cause death or subsequent type 1 or 4b myocardial infarction at one year.

RESULTS

Between 23 March 2015 and 27 June 2019, 1748 participants (mean age 62 years (standard deviation 13), 64% men, mean global registry of acute coronary events (GRACE) score 115 (standard deviation 35)) were randomised to receive early CT coronary angiography (n=877) or standard of care only (n=871). Median time from randomisation to CT coronary angiography was 4.2 (interquartile range 1.6-21.6) hours. The primary endpoint occurred in 51 (5.8%) participants randomised to CT coronary angiography and 53 (6.1%) participants who received standard of care only (adjusted hazard ratio 0.91 (95% confidence interval 0.62 to 1.35), P=0.65). Invasive coronary angiography was performed in 474 (54.0%) participants randomised to CT coronary angiography and 530 (60.8%) participants who received standard of care only (adjusted hazard ratio 0.81 (0.72 to 0.92), P=0.001). There were no overall differences in coronary revascularisation, use of drug treatment for acute coronary syndrome, or subsequent preventive treatments between the two groups. Early CT coronary angiography was associated with a slightly longer time in hospital (median increase 0.21 (95% confidence interval 0.05 to 0.40) days from a median hospital stay of 2.0 to 2.2 days).

CONCLUSIONS

In intermediate risk patients with acute chest pain and suspected acute coronary syndrome, early CT coronary angiography did not alter overall coronary therapeutic interventions or one year clinical outcomes, but reduced rates of invasive angiography while modestly increasing length of hospital stay. These findings do not support the routine use of early CT coronary angiography in intermediate risk patients with acute chest pain and suspected acute coronary syndrome.

TRIAL REGISTRATION

ISRCTN19102565, NCT02284191.