a Department of Cardiology, University Hospital of Rangueil, 1, avenue Jean-Poulhès, TSA50032, 31059 Toulouse cedex 9, Franceb Department of Epidemiology, UMR 1027, Inserm, Toulouse University, Toulouse, Francec Department of Radiology, University Hospital of Rangueil, Toulouse, Franced Cardiac Imaging Centre, University Hospital of Rangueil, Toulouse, Francee Emergency Department, University Hospital of Rangueil, Toulouse, France
Received 5 December 2011; received in revised form 8 April 2012; accepted 18 April 2012Available online 27 June 2012
Background. — Multislice computed tomography coronary angiography (MSCT-CA) is feasible inthe emergency department (ED) for ruling out obstructive coronary artery disease (CAD).Aim. — To investigate a diagnostic strategy using MSCT-CA for the early triage of patients pre-senting to the ED with acute chest pain suggestive of acute coronary syndrome (ACS), accordingto the medium-term incidence of clinical events.
Abbreviations: ACS, Acute coronary syndrome; BMI, Body mass index; CAD, Coronary artery disease; CI, Confidence interval; ECG,lectrocardiogram; ED, Emergency department; FFR, Fractional flow reserve; GRACE, Global Registry of Acute Coronary Events; ICA, Inva-ive coronary angiography; MACE, Major adverse coronary events; MSCT-CA, Multislice computed tomography coronary angiography; mSv,illisievert; SD, Standard deviation; TIMI, Thrombolysis In Myocardial Infarction.∗ Corresponding author. Fax: +33 5 61 32 33 18.
MOTS CLÉSScanner coronaire ;Athérosclérose ;Maladie coronaire ;Syndrome coronarienaigu
RésuméContexte. — Le coroscanner est un examen diagnostique accessible dans les services d’urgencespour éliminer la présence d’une maladie coronaire.Objectifs. — Nous avons étudié l’intérêt du scanner coronaire pour le triage précoce des patientsse présentant aux urgences avec un syndrome douloureux thoracique évocateur de syndromecoronarien aigu sans critère de haut risque, basé sur le devenir clinique à moyen terme.Méthodes. — Nous avons réalisé une étude monocentrique prospective observationnelle decohorte incluant 123 patients souffrant d’un syndrome coronarien aigu à risque bas ou inter-médiaire. Un scanner coronaire a été réalisé à la phase diagnostique initiale avec un scannerbi-tube 64 barrettes avec synchronisation rétrospective à l’électrocardiogramme. Les patientssans ou avec des lésions coronaires minimes étaient autorisés à quitter le service d’urgence.Les incidences des décès, infarctus du myocarde et revascularisation myocardique ont étéprospectivement collectées à un an.Résultats. — Selon les résultats du scanner, 93 patients (75,6 %) avaient des plaques athéro-mateuses coronaires inférieures ou égales à 50 %. Une coronarographie a été réalisée chez29 patients (23,6 %). Le scanner coronaire a identifié dix patients (8,13 %) ayant une maladiecoronaire obstructive ayant justifié une revascularisation myocardique. Ces dix patients avaientun score de risque TIMI bas entre 0 et 2 et huit patients avaient un score de GRACE bas. La doseeffective moyenne du scanner coronaire a été de 16,3 ± 6,4 mSv. Le suivi médian a été de15 mois. Aucun patient (IC 95 % 0—3,0 %) n’a eu d’événement cardiovasculaire majeur durant lesuivi prospectif.Conclusions. — Le scanner coronaire apparaît être un outil diagnostique initial utile dans lesservices d’urgences. Un scanner coronaire négatif autorise un départ rapide et sûr du patientdu fait de la forte valeur prédictive négative. Toutefois, dans 8,13 % de syndrome douloureuxthoracique à risque bas ou intermédiaire, le scanner détecte une maladie coronaire obstructiveet permet une stratégie diagnostique et thérapeutique complémentaire spécifique. La réductionde l’irradiation par le scanner est nécessaire avant l’acceptation de cet examen dans la pratiquequotidienne.
MSCT-CA) is accurate compared with invasive coronaryngiography (ICA) and is feasible and practical in the ED6—11]. MSCT-CA has a high ability to rule out obstruc-ive coronary artery disease (CAD) [12,13]. Since 2008,
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SCT-CA has become part of the management strategy forome patients with ACS without high-risk features in ournstitution, in agreement with American and French recom-endations [14,15]. However, the relevance of this strategy
s still controversial [16], even in our institution. The paucityf data on the incremental value of further diagnostic testsnd on the prognosis of patients released from the ED after aormal MSCT-CA explains why it is difficult for health insti-utes to develop guideline recommendations with a greatevel of evidence [3,16].
Therefore, we assessed a diagnostic strategy using MSCT-A for the early triage of patients presenting to ED withcute chest pain suggestive of ACS, according to theedium-term incidence of clinical events.
ethods
opulation
e conducted a single-centre, prospective, observationalohort study in low-risk to intermediate-risk ACS patients.rom April 2008 to September 2009, 123 patients presentingo the ED of the University Hospital of Rangueil in Toulouse,rance, were prospectively enrolled. Patients presenting tohis ED with acute chest pain or other recent-onset angina-ike symptoms, an ECG without myocardial ischemia-relatedbnormalities and without elevation of cardiac troponinould be prospectively enrolled. Standard chest pain assess-ent by the ED physicians included:detailed assessment of clinical history;CAD risk factors; description of symptoms;physical examination;18-lead ECG; chest X-ray;and measurement of cardiac biomarkers (troponin I),repeated six hours later.
Patients could be enrolled at the ED if their Global Reg-stry of Acute Coronary Events (GRACE) risk score was lesshan 119 (http://www.outcomes-unmassmed.org/grace).
Patients were excluded if aortic dissection or pulmonarymbolism was particularly suspected; in these cases, atandard dedicated diagnostic algorithm was performed.atients were also excluded if there was evidence for a causef chest pain other than myocardial ischemia. Patients werexcluded if the chest pain was related to a high-risk ACS.igh-risk criteria were:ST-segment elevation acute myocardial infarction;diabetes mellitus known for more than 10 years;a rise in serum cardiac troponin concentration;ECG changes suggesting ischemia;GRACE risk score greater or equal to 119;history of CAD; and acute heart failure.
These patients were admitted to the cardiology inten-ive care unit and ICA was performed according to Europeanecommendations [1].
After this evaluation, the ED physician was free to includehe patient in the study if further immediate coronary eval-
ation was considered as being required. If the patient hado CAD risk factor, atypical chest pain and a very low GRACEcore, the ED physician could allow patient to leave the EDith an appointment to see a cardiologist a few days later.
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he safety and efficiency of an immediate MSCT-CA has notet been demonstrated in such cases.
At this stage, patients were not included if MSCT-CA wasot feasible or was contraindicated because of: age less than8 years; allergy to contrast agents; pregnancy; atrial fibril-ation or frequent ectopy; uncontrolled heart rate; inabilityo perform a 20-second breath hold; body mass index (BMI)reater than 40; or renal failure (creatinine clearance lesshan 60 mL/min/m2). If the patient was suitable for inclu-ion, a cardiologist was called to provide a full explanationf the strategy. The patient was then included if they gavenformed consent. Clinical history, CAD risk factors andescription of symptoms were checked by a cardiologist athe ED. Thrombolysis In Myocardial Infarction (TIMI) [17] andRACE risk scores were calculated.
echnique and image reconstruction
SCT-CA was performed using dual-source 64-slice com-uted tomography (SOMATOM, Dual-Source Definition;iemens Medical Solutions, Erlangen, Germany) with ret-ospective electrocardiographic gating. Before acquisition,he patients received beta-blockers, targeting a heart rateess or equal to 65 beats/min. The acquisition started at theevel of the carina and stopped below the heart after injec-ion of iodine contrast. Calcium scoring was not studied (i.e.nly one acquisition was performed). Moreover, no delayedcquisition was performed in order to limit radiation expo-ure. The acquisition delay was computed automatically bylacing a region of interest in the ascending aorta, with atart threshold of 150 Hounsfield units. A biphasic injectionsing a dual-head injector consisted of a bolus of 1.5 cc/kg ofontrast agent (iomeprol) at a concentration of 400 mg/mLIomeron 400, Bracco-Byk, Milan, Italy) followed by a salineush. Collimation was 64 × 0.6 mm with a gantry rotation of30 ms and a pitch of 0.36. The reference tube current was20 mA. The tube voltage was adjusted to the patient’s bodyeight: 80 kV for patients less than 70 kg, 100 kV for patientseighing 70—90 kg and 120 kV for patients above 90 kg. Rawata were reconstructed with a slice thickness of 0.75 mmvery 0.5 mm using a standard kernel, every 10% of the R-
interval. Current intensity modulation was systematicallypplied to reduce radiation during systolic phases (maximalurrent intensity between 30—40% and 70—80%, dependingn the heart rate). The tube modulation programme CAREose 4D was also used (Siemens Medical Solutions, Erlangen,ermany).
For each patient, the images were uploaded to a dedi-ated workstation (Leonardo; Siemens, Erlangen, Germany)nd interpreted by two experienced cardiac radiologists whoere aware of the clinical data. One, two or three phasesere kept for the analysis, depending on the heart rate of
he patient and the presence of motion artifacts. Multipla-ar reconstruction, curvilinear multiplanar reconstruction,olume rendering technique and maximum intensity pro-ection were used for the analysis (Circulation Software;iemens, Erlangen, Germany). A 17-segment model of theoronary arteries and a three-point grading score (normal,
ild [< 50% luminal diameter narrowing], stenosis [≥ 50%])ere used to evaluate coronary stenosis; however, only
egments greater than 1.5 mm in diameter were analysed.atients were classified according to the maximal lesion.
MSCT-CA was considered as ‘negative’ when there was no ormild CAD. MSCT-CA was considered as ‘positive’ when therewas at least a single coronary artery stenosis greater or equalto 50%. MSCT-CA was also considered as ‘positive’ when itwas not interpretable.
Diagnostic pathway
The diagnostic pathway of the patient according to theMSCT-CA result is summarized in Fig. 1. Patients withoutCAD or with mild lesions on MSCT-CA were discharged earlyfrom the ED without treatment after other possible causesof chest pain had been investigated. All patients with steno-sis greater or equal to 50% on MSCT-CA were admitted to thecardiology unit and had ICA. Qualitative ICA was performedby one of the nine physicians from the catheterization lab-oratory of the University Hospital of Rangueil in Toulouse.The interventional cardiologist was aware of the resultsof the MSCT-CA. The ICA was visually interpreted by twoobservers. Automated analysis stenosis severity assessmentwas also applied for lesions greater or equal to 50%, with anautomated edge-detection system (Medical QCA/CMS; MedisImaging System, Leiden, The Netherlands). A functionalstress test (myocardial perfusion imaging, stress echocardio-graphy or exercise treadmill test, according to availability)or fractional flow reserve (FFR) was performed to assess thehaemodynamic significance of intermediate stenosis greateror equal to 50% but less or equal to 70% and direct myocar-dial revascularization indication. Only Lesions with an FFRless than 0.80 at maximum hyperaemia were consideredfunctionally significant and were treated by mechanicalrevascularization [18]. Only severe lesions and intermediatelesions with proven myocardial ischaemia were consideredfor myocardial revascularization. Non-obstructive CAD isdefined by stenosis greater or equal to 50% but less or equalto 70% on ICA with a negative stress test or FFR test. Medi-cal therapy, including aspirin, beta-blockers and statins, wasproposed for patients with non-obstructive CAD. ObstructiveCAD is defined by stenosis greater or equal to 70% on ICA orless or equal to 50% on ICA with an abnormal functional stresstest or FFR less than 0.80. A revascularization strategy asso-ciated with medical therapy was proposed for obstructiveCAD patients.
Follow-up
All patients or proxies and general practitioners were con-tacted by the first investigator (S.H.) by a telephone recallbetween January 2010 and April 2011. Clinical status wasqueried. During follow-up, death or a history of myocar-dial infarction, myocardial revascularization or heart failurewas searched for. The main outcome criteria were majoradverse coronary events (MACE), defined as myocardialinfarction, myocardial revascularization and cardiovasculardeath occurring after the primary hospitalization. For thepatients followed in our cardiology department, the follow-up data in the medical information file were noted.
Statistical analysis
Continuous variables are expressed as mean ± standard devi-ation (SD) and the median is provided if the distribution
mMni
341
f the variable departed from normality. Categorical varia-les are expressed as total number (percentage). The SCOREethod with continuity correction was used to estimate the
5% confidence interval (CI) for proportions [19]. Student’s test was performed to compare means of quantitative varia-les between groups. Fisher’s exact test was performed toompare proportions. A p value less than 0.05 was con-idered to be statistically significant. All calculations wereone using MedCalc statistical software, version 8.0 (Med-alc Software, Mariakerke, Belgium).
esults
total of 123 patients constituted our final population.tudy population characteristics are listed in Table 1. Preva-ence of CAD and patient course are presented in Fig. 1.n two cases (1.63%), MSCT-CA analysis was not possibleecause of kinetic artefacts due to high heart rate. Of thesewo patients, one had a negative stress echocardiographynd was discharged without MACE during a median 15-monthollow-up. The other patient had ICA that revealed signifi-ant stenosis of the left anterior descending artery and hadyocardial revascularization by angioplasty and one stent.ccording to MSCT-CA results, 93 patients (75.6%) had nor mild CAD and 28 patients (22.8%) had stenosis greater orqual to 50%. ICA was performed in 29 patients (23.6%). Aomplementary diagnostic functional stress test or FFR wasecessary in 20 patients. A negative FFR was measured inhree patients. Obstructive CAD requiring myocardial revas-ularization was diagnosed in 10 patients (8.13%). Stenosisreater or equal to 70% was observed in nine patients; oneatient had stenosis between 50% and 70% and a positivetress echocardiography. Of these 10 patients, eight weret low risk and two were at intermediate risk. Of the 28atients with stenosis greater or equal to 50% on MSCT-CA,9 patients had stenosis less or equal to 70% on ICA and aegative FFR/functional stress test and were classified asaving non-obstructive CAD. Patient characteristics accord-ng to CAD severity are listed in Table 1. In Table 2, patientsnally diagnosed with obstructive CAD are compared withhe remaining sample (i.e. patients with no or mild CADccording to MSCT-CA results and those with MSCT-CA steno-is greater or equal to 50% but without obstructive CADccording to ICA and FFR/functional stress test). Chest painhought to be typical angina pectoris was a factor signifi-antly associated with obstructive CAD according to Fisher’sxact test (p = 0.0449). Mean age was higher in patientsith obstructive CAD (p = 0.0476). The probability of havingbstructive CAD after a positive MSCT-CA was 35.7%.
The mean estimated effective dose of MSCT-CA was6.3 ± 6.4 mSv (3.0—33.7 mSv). Mean radiation exposure wasigher in young people (p = 0.024), patients with a high BMIp = 0.0386) and men (p = 0.045). No acute renal insufficiencyr beta-blocker side-effects were reported.
Median follow-up was 15 (7—30) months. Follow-up dataere available for every patient. No patient (95% CI 0—3.0%)ad MACE during follow-up. Of the 10 patients who had
yocardial revascularization at the first step, none hadACE during follow-up. Of the 93 patients who had aegative MSCT-CA, none (95% CI 0—5.0%) had MACE dur-ng follow-up. The negative predictive value of MSCT-CA
Data are mean ± standard deviation (min—max) or number (%). CAD: coronary artery disease; FFR: fractional flow reserve; GRACE: Global Registry of Acute Cardiac Events; ICA: invasivecoronary angiography; MSCT-CA: multislice computed tomography coronary angiography; TIMI: Thrombolysis in Myocardial Infarction.a Absence of CAD on MSCT-CA.b The patient with non-diagnostic MSCT-CA but obstructive stenosis on ICA was counted in this group.
Early triage of ACS patients: 64-slice CTA 343
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Figure 1. Study population.
for MACE occurrence during follow-up was 100% (95% CI95—100%).
Discussion
In the present study, MSCT-CA identified ten patients (8.13%)with obstructive CAD requiring myocardial revascularizationfrom a sample of 123 patients with acute chest pain at low-to-intermediate risk presenting to an ED. These ten patientshad a low TIMI risk score (between 0 and 2) and eight patients(80%) had a low GRACE risk score. These results confirm theneed for further testing in low-risk chest pain patients andthe value of MSCT-CA.
Furthermore, 75.6% of patients with acute chest painhad no CAD or coronary artery lesions less or equal to 50%on MSCT-CA and did not have an adverse coronary eventor death (95% CI 0—3%) during a median follow-up of 15months. Our results correspond with those reported by Hol-lander et al. in the USA and Schlett et al. in Germany [20,21].Negative MSCT-CA could therefore allow immediate and safedismissal from the ED of these patients with acute chestpain without ECG abnormalities or a rise in serum cardiacbiomarkers. Given the large number of such patients, earlyMSCT-CA may significantly improve patient management inthe ED.
MSCT-CA offers direct visualization of the coronary arter-
ies but does not provide information on inducible ischemia.As we did not perform a stress test systematically, we can-not compare our results with another diagnostic strategybased on a stress test. In our institution, stress tests such as
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tress echocardiography, nuclear myocardial perfusion imag-ng, magnetic resonance imaging and the standard treadmillest are not available 24 hours/day. Conversely, MSCT-CA isvailable quickly. The feasibility of MSCT-CA in the ED is noturrently applicable in all centres 24 hours/day. However,ur results confirm that further testing in low-risk chest painatients is necessary. According to previous studies, a diag-ostic strategy with MSCT-CA could shorten the length oftay, decrease costs, reduce the need for ICA and improverognosis compared with chest pain unit management withCA or the stress tests in use at the moment [22—25]. Givenur results and these studies, MSCT-CA may be one of therst triage examinations that should be widely available4 hours/day, particularly in small centres.
The probability of having obstructive CAD in the pres-nce of coronary artery stenosis greater or equal to 50%n MSCT-CA is only 35.7%. The clinical impact of a posi-ive result is limited and may require additional non-invasivenvestigation before ICA. Patients with acute chest painnd coronary artery stenosis greater or equal to 50% onSCT-CA but without haemodynamic significance on FFR or
unctional stress test seemed to have no coronary event oreath under medical treatment. This sample of patients wasow (n = 18, 15%). This observation is in agreement with theesults of Pijls et al. [26]. Given these results, we wouldecommend performing a functional test without radiation,uch as stress echocardiography, when MSCT-CA suggests the
resence of coronary artery stenosis greater or equal to0%, reserving ICA for a positive or inconclusive functionalest result. For patients in whom MSCT-CA suggests severeesions, ICA may be required to confirm the anatomy of the
344 S. Hascoët et al.
Table 2 Risk markers of obstructive coronary artery disease.
Characteristic No, mild or non-obstructive CAD(n = 113)
CAD: coronary artery disease; CI: confidence interval; GRACE: Global Registry of Acute Cardiac Events; TIMI: Thrombolysis in MyocardialInfarction.Data are mean ± standard deviation or number (%).a Student’s t test was performed to compare mean age; Fisher’s exact test was performed to compare proportions.
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esions detected. In these cases, in our experience, FFR pro-ides a fast assessment of the haemodynamic significancef the ambiguous lesions during the same examination andmproves the myocardial revascularization indication deci-ion. Fortuitous discoveries of non-obstructive CAD will alsollow early risk factor modification, thereby potentially pre-enting future cardiac events. But the relevance of thispproach needs to be evaluated in large dedicated studies3].
There was variety in the patients’ ages (19 to 86 years)nd levels of risk (very low risk to intermediate risk). Thetudy population represented only a sample of all patientsresenting to the ED with chest pain. This makes it dif-cult to define the cohort of patients that is best suitedo this new technology. We excluded patients at high risknd patients with known CAD, thereby limiting applicabilityor many ED patients; but MSCT-CA does not improve risktratification and early ICA is recommended [1,27]. We alsoxcluded patients with contraindications to MSCT-CA. But iteems that approximately 80% of non-CAD patients under-oing a rule-out ACS process could be suitable for MSCT-CA28]. Almost one-quarter of these are from very low-riskroups and the risk/cost-benefit ratio of further testing isubious. We identified two main factors that could improvehe pretest probability of having obstructive CAD: older agend typical angina-like symptoms. Therefore, in a settingf a low-risk young patient with highly atypical symptoms,o additional diagnostic evaluation may be required. Theecent recommendations of the National Institute for Healthnd Clinical Excellence in the UK proposed that the indi-ation for MSCT-CA in ACS at low risk should therefore be
ased on the pretest prevalence of CAD, according to age,ex, cardiovascular risk factors and chest pain characteris-ics [3]. The results of our study confirm the merits of theseew recommendations.
irta
A significant issue with MSCT-CA is radiation exposure.ean estimated effective dose is high (estimated as 16.3Sv) despite appropriate image acquisition protocol. Guéret
t al. reported a higher mean exposure of 19 mSv in a Frenchulticentre observational study carried out at the same time
29]. Chow et al. reported a similar estimated effectiveose of 15 mSv in a similar sample of patients with acutehest pain in an ED in an experimental centre in Canada30]. Little is still known about the long-term effects ofadiation. An increasing risk of cancer is suspected above0 mSv [31].
onclusion
SCT-CA is a promising technology for chest pain evaluationn the ED. Our results suggest that it could be a useful andecessary initial triage tool. When the MSCT-CA result is neg-tive, it allows safe and early discharge because of its highegative predictive value. In a significant number of low-riskCS patients, MSCT-CA detects severe coronary lesions andllows dedicated further diagnostic and therapeutic inter-ention. Some people suggest that it should be a first-lineest [32]. Our results are a validation of the French recom-endations published in 2009 [15]. New guidelines from the
uropean Society of Cardiology for the management of ACSow recommend (with a class IIa) the use of MSCT-CA as anlternative to ICA to exclude ACS when there is a low-to-ntermediate likelihood of CAD and when troponin and ECGre inconclusive [33]. But the inability of anatomical find-ngs to prove the presence of ischaemia and the cancer risk
nduced by radiation exposure still raise concerns about theelevance of this strategy. The results of our study deserveo be completed by multicentre analysis and compared with
diagnosis strategy based on a stress test alone.
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Disclosure of interest
The authors declare that they have no conflicts of interestconcerning this article.
References
[1] Bassand JP, Hamm CW, Ardissino D, et al. Guidelines for thediagnosis and treatment of non-ST-segment elevation acutecoronary syndromes. Eur Heart J 2007;28:1598—660.
[2] Braunwald E, Antman EM, Beasley JW, et al. ACC/AHA2002 guideline update for the management of patients withunstable angina and non-ST-segment elevation myocardialinfarction — summary article: a report of the American Col-lege of Cardiology/American Heart Association task force onpractice guidelines (Committee on the management of patientswith unstable angina). J Am Coll Cardiol 2002;40:1366—74.
[3] [3] National Institute for Health and Clinical Excellence. Chestpain of recent onset: assessment and diagnosis of recentonset chest pain or discomfort of suspected cardiac origin.NICE guideline. 2010;CG95: available at: http://guidance.nice.org.uk/CG95/NICEGuidance/pdf/English.
[4] McCarthy BD, Beshansky JR, D’Agostino RB, et al. Misseddiagnoses of acute myocardial infarction in the emergencydepartment: results from a multicenter study. Ann Emerg Med1993;22:579—82.
[5] Pope JH, Aufderheide TP, Ruthazer R, et al. Missed diagnoses ofacute cardiac ischemia in the emergency department. N EnglJ Med 2000;342:1163—70.
[6] Goldstein JA, Gallagher MJ, O’Neill WW, et al. A randomizedcontrolled trial of multi-slice coronary computed tomogra-phy for evaluation of acute chest pain. J Am Coll Cardiol2007;49:863—71.
[7] Hoffmann U, Bamberg F, Chae CU, et al. Coronary com-puted tomography angiography for early triage of patients withacute chest pain: the ROMICAT (rule out myocardial infarctionusing computer assisted tomography) trial. J Am Coll Cardiol2009;53:1642—50.
[8] Hoffmann U, Nagurney JT, Moselewski F, et al. Coronary multi-detector computed tomography in the assessment of patientswith acute chest pain. Circulation 2006;114:2251—60.
[9] Hollander JE, Chang AM, Shofer FS, et al. Coronary com-puted tomographic angiography for rapid discharge of low-riskpatients with potential acute coronary syndromes. Ann EmergMed 2009;53:295—304.
[10] Pundziute G, Schuijf JD, Jukema JW, et al. Prognostic valueof multislice computed tomography coronary angiography inpatients with known or suspected coronary artery disease. JAm Coll Cardiol 2007;49:62—70.
[11] Rubinshtein R, Halon DA, Gaspar T, et al. Impact of 64-slice cardiac computed tomographic angiography on clinicaldecision-making in emergency department patients with chestpain of possible myocardial ischemic origin. Am J Cardiol2007;100:1522—6.
[12] Janne d’Othee B, Siebert U, Cury R, et al. A systematic reviewon diagnostic accuracy of CT-based detection of significantcoronary artery disease. Eur J Radiol 2008;65:449—61.
[13] Sirol M, Sanz J, Henry P, et al. Evaluation of 64-slice MDCT inthe real world of cardiology: a comparison with conventionalcoronary angiography. Arch Cardiovasc Dis 2009;102:433—9.
[14] Hendel RC, Patel MR, Kramer CM, et al.ACCF/ACR/SCCT/SCMR/ASNC/NASCI/SCAI/SIR 2006 appropri-
ateness criteria for cardiac computed tomography and cardiacmagnetic resonance imaging: a report of the American Collegeof Cardiology Foundation Quality Strategic Directions Commit-tee Appropriateness Criteria Working Group, American College
[
345
of Radiology, Society of Cardiovascular Computed Tomography,Society for Cardiovascular Magnetic Resonance, AmericanSociety of Nuclear Cardiology, North American Society forCardiac Imaging, Society for Cardiovascular Angiography andInterventions, and Society of Interventional Radiology. J AmColl Cardiol 2006;48:1475—97.
15] Pernès J-M, Sirol M, Chabbert V, et al. Current indications forcardiac CT. Arch Cardiovasc Dis Sup 2009;1:13—22.
16] Hendel RC. Is computed tomography coronary angiographythe most accurate and effective noninvasive imaging tool toevaluate patients with acute chest pain in the emergencydepartment? CT coronary angiography is the most accurateand effective noninvasive imaging tool for evaluating patientspresenting with chest pain to the emergency department:antagonist viewpoint. Circ Cardiovasc Imaging 2009;2:264—75,discussion 75.
17] Antman EM, Cohen M, Bernink PJ, et al. The TIMI riskscore for unstable angina/non-ST elevation MI: a methodfor prognostication and therapeutic decision making. JAMA2000;284:835—42.
18] Tonino PA, De Bruyne B, Pijls NH, et al. Fractional flow reserveversus angiography for guiding percutaneous coronary inter-vention. N Engl J Med 2009;360:213—24.
19] Tobi H, van den Berg PB, de Jong-van den Berg LT. Smallproportions: what to report for confidence intervals. Pharma-coepidemiol Drug Saf 2005;14:239—47.
20] Hollander JE, Chang AM, Shofer FS, et al. One-year outcomesfollowing coronary computerized tomographic angiography forevaluation of emergency department patients with potentialacute coronary syndrome. Acad Emerg Med 2009;16:693—8.
21] Schlett CL, Banerji D, Siegel E, et al. Prognostic value ofCT angiography for major adverse cardiac events in patientswith acute chest pain from the emergency department: 2-year outcomes of the ROMICAT trial. JACC Cardiovasc Imaging2011;4:481—91.
22] Chang SA, Choi SI, Choi EK, et al. Usefulness of 64-slicemultidetector computed tomography as an initial diagnos-tic approach in patients with acute chest pain. Am Heart J2008;156:375—83.
23] Gallagher MJ, Ross MA, Raff GL, et al. The diagnostic accu-racy of 64-slice computed tomography coronary angiographycompared with stress nuclear imaging in emergency depart-ment low-risk chest pain patients. Ann Emerg Med 2007;49:125—36.
24] Goehler A, Ollendorf DA, Jaeger M, et al. A simulation model ofclinical and economic outcomes of cardiac CT triage of patientswith acute chest pain in the emergency department. AJR Am JRoentgenol 2011;196:853—61.
25] Min JK, Shaw LJ, Berman DS, et al. Costs and clinical out-comes in individuals without known coronary artery diseaseundergoing coronary computed tomographic angiography froman analysis of Medicare category III transaction codes. Am JCardiol 2008;102:672—8.
26] Pijls NH, De Bruyne B, Peels K, et al. Measurement of fractionalflow reserve to assess the functional severity of coronary-arterystenoses. N Engl J Med 1996;334:1703—8.
27] Braunwald E, Antman EM, Beasley JW, et al. ACC/AHAguidelines for the management of patients with unstableangina and non-ST-segment elevation myocardial infarction:executive summary and recommendations. A report of theAmerican College of Cardiology/American Heart Associationtask force on practice guidelines (committee on the manage-ment of patients with unstable angina). Circulation 2000;102:1193—209.
28] Hamid S, Bainbridge F, Kelly AM, et al. What proportion ofpatients with chest pain are potentially suitable for com-puted tomography coronary angiography. Am J Emerg Med2010;28:494—8.
29] Guéret P. EVASCAN. Actualités sur les grands essais cliniques I.XXIes Journées européennes de la Société francaise de cardi-ologie. 13 janvier 2011, Paris. XXIes Journées européennes dela Société francaise de cardiologie 2011.
30] Chow BJ, Joseph P, Yam Y, et al. Usefulness of computedtomographic coronary angiography in patients with acute
chest pain with and without high-risk features. Am J Cardiol2010;106:463—9.
31] Brenner DJ, Hall EJ. Computed tomography — an increasingsource of radiation exposure. N Engl J Med 2007;357:2277—84.
S. Hascoët et al.
32] Chang HJ, Chung N. Clinical perspective of coronary computedtomographic angiography in diagnosis of coronary artery dis-ease. Circ J 2011;75:246—52.
33] Hamm CW, Bassand JP, Agewall S, et al. ESC Guidelines forthe management of acute coronary syndromes in patientspresenting without persistent ST-segment elevation: the Task
Force for the management of acute coronary syndromes (ACS)in patients presenting without persistent ST-segment eleva-tion of the European Society of Cardiology (ESC). Eur HeartJ 2011;32:2999—3054.
