: A SELECTION OF ARTICLES CARDIAC MR AND CT. JN Dacher, Rouen

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1 : A SELECTION OF ARTICLES CARDIAC MR AND CT JN Dacher, Rouen

2 Cardiac CT: Consensus Statement Taylor AJ. et al. JACC 2010;56:1864

3 The Asymptomatic Patient

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5 Acute Symptoms Mammen L. et al. JACR 2011;8:12-18

6 CTCA before Non Coronary Cardiac Surgery ICA recommended preoperatively (Task force on the management of valvular heart disease. Eur Heart J. 2007; 28: 230) 161 consecutive patients scheduled for cardiac and thoracic aortic surgery 21 did not undergo surgery 7 were contraindicated to CT 133 pts had CT (45 had medically controlled arrhythmia) 108 diagnostic CTCA studies (Aquilion 64) 93/108 patients had no significant CAD on CTCA No subsequent ICA No ischemic event at follow up (20 months) CT limited mostly by calcium (Agatston score cutoff 579) 2 non cardiac findings: one thymoma, one lung cancer ICA in either non diagnostic (n=25, 18%) or positive CTCA (n=15, 11%) Conclusion: 64d CTCA is sufficient/efficient in a majority of patients, even those with arrhythmia. Catalan P et al. Radiology 2011; 258 :

7 Metaanalysis Prognosis of CTCA 18 studies including 9,592 patients CTCA and clinical follow up Median f/u: 20 months Pooled annualized event rate Obstructive (at least 1 vessel with >50% stenosis) vs. Normal CTCA 8.8% vs. 0.17% for MACE 3.2% vs. 0.15% for death or MI Hulten EA. et al. JACC 2011;57:

8 Metaanalysis Prognosis of CTCA Pooled Negative Likelihood Ratio MACE after normal CTCA (95% CI: ) Positive likelihood ratio : 1.7 (95% CI: ) «the concept that CTCA offers anatomic but not prognostic value compared with widely used functional stress testing is no longer accurate» Hulten EA. et al. JACC 2011;57:

9 Chronic Occlusion: CT Evaluation by CT -length -meander - calcification - difference in attenuation Magro M et al. EuroIntervention 2010; 6: G123 Chow BJW et al. JACC 2011; 57:

10 Cumulative Radiation Dose: Not only CT! 1,097 consecutive patients undergoing index MPI during the 100 first days of 2006 Radiation dose received from 1988 through June 2008 From MPI and all other tests 344 patients (31.4%) received more than 100 msv Einstein, A. J. et al. JAMA 2010;304:

11 Figure. Cumulative Estimated Effective Doses for Myocardial Perfusion Imaging and All Procedures Copyright restrictions may apply. Einstein, A. J. et al. JAMA 2010;304:

12 Radiation Risks associated with CT scans A commentary on Dr. Einstein s paper Use of CT has doubled almost every two years since the 1980s CT may be associated with 1.5-2% of cancers in the USA in the future % of pts not informed of any radiation risks prior to CT scan Too many examinations are performed Fear of litigation Miscommunication Self referral among non radiologists owned imaging clinics Baerlocher MO, Detsky AS. JAMA 2010;304:

13 Dual Energy DE CT Reformat MD Iodine Map DE MRI Hamilton-Craig C et al. JACC Cardiovascular Imaging 2011; 2 : 207-8

14 Spectral CT: Pulm. Embolus Kang M et al. RadioGraphics 2010;30:

15 3T MR Angiography of the Coronaries Achieva 3T, Philips vs. Sensation 64, Siemens Hamdan A et al. JACC Cardiovascular Imaging 2011; 4 : 50-61

16 3T MR Angiography of the Coronaries Direct comparison of the accuracy of MR, MDCT with CA as reference 120 consecutive patients 32 channel 3.0T MR AND 64 slice CT X Ray angiography Pt based analysis Accuracy MR 83% vs CT 87% Se MR 87% vs CT 90% Sp MR 77% vs CT 83% All cases of LM or 3 vessel disease diagnosed by MR Comparable techniques to identify pts who should undergo revascularization Hamdan A et al. JACC Cardiovascular Imaging 2011; 4 : 50-61

17 MR Imaging

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19 CAD: Ischemia / Viability The combination FUNCTION, PERFUSION, DE Primary use of MRI in the following cases Identifying patients with ischemia in cases of rest ECG anomalies, inability to exercise Anatomy of ischemic areas Identifying patients who could benefit of revascularization Dx. of viability under low doses of dobutamine The Committee recognizes the advantages of spectroscopy for early identification of areas of ischemia not detectable by other techniques. Hundley WG et al. JACC 18 Mai 2010

20 Myocardiopathy Indication to evaluate by MRI pts with LV dysfunction, hypertrophy or any cardiac lesion with normal coronaries DCM Increased cardiac enzymes amyloidosis or other infiltrative cardiopathy HCM: Prognostic role of DE, Se MRI > Se ECHO ARVD Syncope / ventricular arrhythmia NCVG (NC/C > 2.3 at end diastole, Petersen criteria) Petersen SE et al. JACC 2005; 46 : 101

21 Acute Myocarditis CMR Qualified of major diagnostic tool T2 edema T1 +/- Gd enhancement DE Friedrich M et al. JACC white paper 2009; 53 : 1475

22 EDEMA DE Eitel I and Friedrich M. JCVMR 2011; 13 : 13

23 MR Imaging of Edema: a primer Eitel I and Friedrich M. JCVMR 2011; 13 : 13

24 ARVD -Consensus Document Major Criteria (MRI) Regional RV akinesia or dyskinesia or dyssynchronous RV contraction And 1 of the following EDRV volume/bsa > 110 ml/m 2 in males, 100 in females RVEF < 40% Minor criteria (MRI) Regional RV akinesia or dyskinesia or dyssynchronous RV contraction And 1 of the following 110 > ED RV volume / BSA > 100 ml/m 2 in males, 100 > ED RV volume / BSA > 90 ml/m 2 in females 45%> RVEF > 40% Marcus FI et al. Eur Heart J 2010; 31 :

25 Heart failure with normal EF: the complementary roles of echocardiography and CMR imaging State of the art paper HFNEF replaced «diastolic heart failure» echo Diastolic function Tissue velocity Strain analysis CMR Systolic function (EF) Myocardial mass Fibrosis Tissue characterization Leong DP et al. JACC Cardiovascular Imaging 2010; 3 : 409

26 Does coronary flow trump coronary anatomy? Gould KL JACC CV Imaging 2009; 2:

27 Myocardial Perfusion Imaging

28 Maximal Hyperemia DS 61.7% Aorta pressure FFR 0.5 LAD pressure Watkins S et al. Circulation 2009; 120 :

29 Validation of MR Myocardial Perfusion Imaging (MPI) with Fractional Flow Reserve (FFR) for the detection of significant coronary heart disease 103 patients with suspected angina MR MPI at 1.5T (IV Adenosine 140 µg.kg -1.min -1 ) 2 blinded observers Gadolinium (0.1 mmol/kg Omniscan) 1 week later; CA with pressure wire studies FFR performed in all patent major vessels Mean distal coronary artery pressure / Mean aortic pressure FFR considered positive if < 0.75 Watkins S et al. Circulation 2009; 120 :

30 Validation of MR Myocardial Perfusion Imaging (MPI) with Fractional Flow Reserve (FFR) for the detection of significant coronary heart disease Results Per segment MR MPI scans identified 121 / 300 positive segments 110 were positive by FFR 168/179 normally perfused segments had FFR > 0.75 Se 91%; Sp 94%; PPV 91%; NPV 94% Per patient 76 patients with perfusion defect on MR MPI 74 had at least one vessel with FFR < 0.75 MR MPI scan falsely positive in 2 patients 25 patients with normal MR MPI 21 had FFR > 0.75 in all vessels 4 False negative patients Se 95%; Sp 91%; PPV 97%; NPV 84% Watkins S et al. Circulation 2009; 120 :

31 FFR vs 3T stress CMR Study population 42 patients, 126 vessels (52 FFR) 27 lesions with FFR < 0.75 MR Sensitivity: 0.82 Specificity: 0.94 Area under the ROC: 0.92 (p<0.0001) Myocardial perfusion reserve Threshold : 1.58 (AUC 0.89; p < ) Lockie T et al. JACC 2011; 57 : 70-75

32 FFR vs 3T stress CMR Lockie T et al. JACC 2011; 57 : 70-75

33 Safety MR Compatible Pace Makers

34 MR Unsafe ACCF/ACR/AHA/NASCI/SCMR 2010 Expert Consensus Document on Cardiovascular MR JACC 2010, May 18

35 «EnRhythm MRI SureScan» 464 patients included in 41 centres MRI 9-12 wks after PM implantation (n=244) vs. No MRI (n=206) 1.5T; max db/dt ; SAR 2 W/kg No MR related complication Follow up (pts and PM) at 1 month after MR Sutton R et al. Trials 2008; 9:68 Wilkoff BL et al. Heart Rhythm Soc 2009 ; Heart Rhythm 2010, Oct 5 Kanal E et al. RSNA 2008 Sommer T et al. European Heart Journal 2008;29:ESC Abstract Supplement

36 «there was no evidence of clinical (bradycardia or tachycardia), subclinical (PM performance) or technical (PM or lead damage) adverse events in patients receiving an MRI» Wilkoff BL et al. Heart Rhythm Soc 2009

37 Atrial pacing capture threshold Ventricular pacing capture threshold Atrial sensing Ventricular sensing Atrial impedance Ventricular impedance MRI Control MRI Control MRI Control MRI Control MRI Control MRI Control Pre-MRI/control visit to 1 month post- MRI/control visit Mean + SD Change

38 In Practice, MR possible if complete system implanted (PM AND LEADS) > 6 wks Pectoral implantation No abandoned device No centering constraint Mean SAR body 2 W/kg (head 3,2) Maximum slew rate: 200 T/m/sec Monitoring HR, BP, O2 Mode «Sure Scan» activated (Medtronic device) Should the rhythmologist be always present?

39 HCM and DE 243 patients with HCM and initial MRI Largely low or symptom free pts Mean follow-up (n=220): 1,090 days 22 events (16 cardiovascular) 20 patients died, 2 survived after adapted electric shock from ICD Relative Risk of DE present on MR imaging 5.47 for all causes of death 8.01 for cardiovascular causes of death Lockie T et al. JACC 2010; 56 :

40 HCM and DE 217 patients with HCM and initial MRI Mean follow-up: 3.1 years 136 cases with DE + Fibrosis/necrosis: 34/136 events (25%) 6/81 (7.4%) in patients without DE Relative risk 3.4, p=0.006 Increased risk with increased fibrosis Impact of fibrosis on haemodynamics Relative risk 2.5 O Hanlon R et al. JACC 2010; 56 :

41 In Conclusion, The various consensus statements published in reinforce the respective roles of CT and MR CMR assessment of RV function by MRI recommended in cases of suspected ARVD Stress MR validated as an alternative to nuclear medicine Stress Dual Energy CT in the next years? Thanks to Jérôme Garot for his paper in Réalités Cardiologiques and to J-François Paul for his alerts