Presentation on theme: "Usefulness of Coronary Computed Tomography Angiography For Early Triage of Patients with Acute Chest Pain - The Rule Out Myocardial Infarction Using Computer."— Presentation transcript:
Usefulness of Coronary Computed Tomography Angiography For Early Triage of Patients with Acute Chest Pain - The Rule Out Myocardial Infarction Using Computer Assisted Tomography (ROMICAT) Trial Udo Hoffmann, Fabian Bamberg, Claudia U. Chae, John H. Nichols, Ian S. Rogers, Sujith K. Seneviratne, Quynh A. Truong, Ricardo C. Cury, Suhny Abbara, Michael D. Shapiro, Jamaluddin Moloo, Javed Butler, Maros Ferencik, Hang Lee, Ik-Kyung Jang, Blair A. Parry, David F. Brown, James E. Udelson, Stephan Achenbach, Thomas J. Brady, John T. Nagurney Department of Radiology, Emergency Medicine, and Cardiology Division, Massachusetts General Hospital and Harvard Medical School, Boston MA
Research Grants: Siemens Medical Solutions, Amersham/GE Healthcare, Bracco Diagnostics, NIH Advisory Boards: Vital Images, Bayer Healthcare/Siemens Medical Solutions Disclosures
Early Risk Stratification and Triage in the ED - 6 Million present with chest pain to ED annually - - ECG, initial biomarkers, and clinical presentation and traditional risk factors – no safe triage possible (Nagurney, JAMA 2006) - low threshold to admit, >80% have no ACS, $8Billion annually healthcare cost - 1-5% of missed ACS cause 20% of ED malpractice costs Improvement of the initial ED evaluation needed!
Preliminary coronary CTA Studies - coronary MDCT is feasible in the acute care setting - low to intermediate risk patients - absence of CAD has 100% NPV for ACS – found in 40% of patients Hoffmann et al Circulation very low risk patients - CT may be cost saving alternative to myocardial perfusion stress testing Raff et al JACC normal coronary CTA has excellent NPV for MACE within 15 months Rubinshtein et al. Circulation 2007
Remaining Questions for Patient Management 1. Confirmation in larger cohorts 2. Safety of Stenosis based Triage 3. Relevance of detected Stenosis 4. Incremental Value of non-calcified plaque for exclusion of ACS
ROMICAT I - Specific Aims 1. Determine the prevalence of coronary atherosclerotic plaque and stenosis in patients with acute chest pain and low to intermediate for ACS 2. Determine the diagnostic accuracy of these findings for ACS 3. Determine whether this information is incremental to current risk assessment
ED t Acute Chest Pain Neg. ECG Neg. Trop Index Hospitalization Observational, double-blinded Cohort Study Cardiac CT Analysis - blinded to caregiver and subjects 1.Presence of atherosclerotic plaque per coronary segment a.Calcified plaque b.Non-calcified plaque 2.Presence of significant coronary artery stenosis (>50%) 6 month FU Standard clinical care ROMICAT I – Study Design
Inclusion Criteria ->5 min of chest pain <24h -Normal initial Biomarker -Admitted to Rule out MI -Normal sinus rhythm Exclusion Criteria - positive initial Troponin - D iagnostic ECG changes - Creatinine >1.3 mg/dl -Known CAD Primary Endpoint ACS* (NSTEMI or UAP) during Index Hospitalization and MACE during 6- month follow-up adjudicated by independent committee *According to AHA/ACC/ESC Guidelines ROMICAT I - Methods Coronary MDCT -64-slice MDCT (Siemens, Forchheim, Germany) -Beta-Blocker if HR>65 bpm, Nitro -~20 ml + 80ml contrast agent (Iodhexodol 320) - tube current: ~850 mAs, tube voltage: 120 kV
Protocol Eligible Subjects (n = 658) Enrolled Subjects (n = 412) Study Population (n = 368) Physician Denied (n = 19) Patient Refusal (n = 124) Missed to Ongoing Recruitment (n = 103) Incomplete Scan (n=17) Interference with Clinical Care (n = 10) Claustrophobia/Nausea (n = 3) Contrast Extravasation (n = 3) Scanner Malfunction (n = 1) Complete Scan (n=27) History of Stent Placement (n = 10) History of CABG (n = 17) 18 month Screening and Enrollment
ROMICAT I – Demographics and Risk Factors Age (years, mean SD) 52.7±12 Male Gender (n, %)223 (61%) Race (n, %) African American Caucasian Asians Others 31 (8%) 313 (85%) 4 (1%) 20 (6%) No. of risk factors (median, IQR)2 (1) TIMI Score (low/intermediate/high) in %94.3/ 5.4/ 0.3 ACS during index hospitalization (%, n) Unstable angina pectoris (%, n) Myocardial infarction (%, n) 31 (8%) 23 (74%) 8 (26%) MACE during six month follow- up (%, n): Recurrent chest pain: Outpatient evaluation (PCP) Readmission without testing Readmission with testing 0 68 (18%) 50 (74%) 5 (7%) 13 (19%)
ROMICAT I – Prevalence of Plaque and Stenosis No CAD % (no plaque and no stenosis) N= 185/368 Significant stenosis detected or not excluded % N= 68/368 Non-obstructive Plaque % N= 115/368 CAD categories with relevance for early triage of patients with ACP in the ED
ROMICAT I – CAD and ACS No CAD Nonobstructive Plaque Significant stenosis detected or not excluded No ACS 7 ACS non-stenotic ACS small vessel disease 24 ACS
NSTEMI with significant stenosis 40-year old male who presented 3 hours after the onset of substernal chest pain, inconclusive initial evaluation in the ED, Troponin positive 8 hours after ED presentation, underwent invasive coronary angiography with stenting of an 80% mid LAD
NSTEMI without significant stenosis in CT
NSTEMI with small vessel disease 59-year old female with typical chest pain, non- diagnostic ECG and negative serial Troponin, coronary CTA – plaque in OM 1, invasive coronary angiography demonstrates 95% stenosis of the PDA
NSTEMI with PDA stenosis
ROMICAT I – Diagnostic Accuracy Sens: 100% ( ) NPV: 100% ( ) Spec: 54% ( ) PPV: 17% ( ) ACS No ACS Plaque No Plaque Sens: 77% ( ) NPV: 98% ( ) Spec: 87% ( ) PPV: 35% ( ) ACS No ACS Sign. Stenosis No Stenosis Triage Criterion: Presence of any plaque 2. Triage Criterion: Presence of significant Stenosis (>50%)
Results – Stenosis and ACS specificity of significant stenosis for ACS was lower in subjects 65 years of age (58% vs. 91%) because of increased prevalence of CAC (84% vs. 39%; p<0.0001) in 34 patients a significant stenosis was detected 20 had ACS 14 had no ACS or MACE after 6 months severe RCA lesion, no regional LV dysfunction, normal stress SPECT study, diagnosis of non cardiac chest pain.
Incremental Value of coronary CTA to TIMI AUC for the detection of ACS during index hospitalization Extent of plaque, presence of stenosis, TIMI risk score (AUC: 0.88, 0.82 vs. 0.63; respectively, all p<0.0001).
Summary - confirmation - Absence of any CAD in 50% of patients - 100% NPV for ACS – may enable early safe and early discharge from the ED - triage criterion of 50% stenosis is not perfect because of non-stenotic ACS and limited spatial resolution of coronary CTA - significant stenosis is detected in 10% of patients by coronary CTA – about 40% of these were discharged with a diagnosis of non-cardiac chest pain - incremental value of non- calcified plaque for early triage is limited
Thank you! Cardiac MR PET CT Program Fabian Moselewski, Maros Ferencik, Suhny Abbara, Ricardo C. Cury, Thomas J. Brady, Javed Butler, Nina Dannemann, Michael Shapiro, Sujith Seneviratne, Ian Rogers, John Nichols, Ian Rogers, Quynh Truong, Christopher Schlett, Sam Lehman, Sujith Seneviratne, Ron Blankstein, Khuram Nasir Department of Emergency Medicine John T. Nagurney, David F.M. Brown, Blair Parry Cardiology Division Claudia U. Chae, Ik Kyung Jang, Rob Gerszten Harvard Public School of Health Scott Gazelle, Joseph Ladapo, Milton Weinstein