Non Invasive Cardiology First Coast Heart and Vascular Cardiac Imaging Echo/Coronary CT/ CMR Millee Singh DO Non Invasive Cardiology First Coast Heart and Vascular

Introduction Heart Failure is defined as a syndrome consisting of symptoms and sign resulting from an abnormality of cardiac structure and or function Multiple imaging modalities are currently available to aid is diagnosis, etiology and treatment of heart failure

Diagnosis Echocardiogram is the first line cardiovascular imaging for diagnosis Advantages : Widely available Portable Low cost Non invasive Disadvantages Poor acoustic windows It allows us to see : Cardiac structure (wall dimensions, volume, geometry, valvular and pericardial abnormalities) Function analysis which includes systolic vs diastolic dysfunction

Diagnosis CMR is a complementary imaging modality in HF Gold standard for LV and RV volumes, EF and in vivo tissue characterization Limitations: Claustrophobia Renal failure MRI Conditional Devices Timing for test

Etiology of Heart Failure Many modalities can assist : Echo CCTA CMR Stress testing With SPECT / PET

Etiology of Heart Failure Stress testing is the traditional noninvasive approach to detecting obstructive coronary artery disease It provides physiologic evidence of clinically significant coronary artery stenosis by demonstrating the effects of diminished coronary flow reserve through : Symptoms Characteristic changes on EKG Myocardial perfusion defects on scintigraphy/ regional wall motion abnormalities on echo

Ischemic Etiology of HF Nondiagnostic findings or strong clinical suspicion for Ischemic cause  need for direct anatomical assessment Catheter-based angiography is: Expensive Associated with a small risk OR Serious complications due to the invasive nature

CCTA Noninvasive coronary arteriography was first described for computed tomography (CT) in 1995 Cardiac and coronary CT imaging — Coronary CT angiography (CCTA) has a relatively low technical burden for both the operator and patient The scanning time to acquire a three-dimensional dataset of the entire heart can take as little as 5 seconds Most CCTA procedures are currently performed with multidetector row or multislice (MDCT or MSCT) scanners Contrast: 60 to 120 mL is injected intravenously at a rate of 2 to 5 mL/min Moshage WE, Achenbach S, Seese B, Bachmann K, Kirchgeorg M;coronary artery stenoses: three-dimensional imaging with electrocardiographically triggered, contrast agent-enhanced, electron-beam CT.Radiology. 1995;196(3):707 Moshage WE, Achenbach S, Seese B, Bachmann K, Kirchgeorg M;coronary artery stenoses: three-dimensional imaging with electrocardiographically triggered, contrast agent-enhanced, electron-beam CT.Radiology. 1995;196(3):707

CCTA Limitations  poor imaging Heart rate greater than 60 or 70 beats/min- poor temporal resolution Irregular heart rhythm Inability to sustain a breath hold for at least five seconds Severe coronary calcification or the presence of coronary artery stents Segments with a diameter <1.5 mm can usually not be assessed for stenosis (distal coronary artery segments and some side branches) since image reconstruction artifacts related to radiodense material such as calcium or metal can obscure the coronary artery lumen In most cases, 60 to 120 mL is injected intravenously at a rate of 2 to 5 mL/min. Thus, CCTA is contraindicated in patients with a history of allergy to iodinated contrast medium and relatively contraindicated in patients at high risk for contrast nephropathy (eg, patients with diabetes and a serum creatinine concentration above 2.0 mg/dL Meijboom et. al ;Diagnostic accuracy of 64-slice computed tomography coronary angiography: a prospective, multicenter, multivendor study. J Am Coll Cardiol. 2008;52(25):2135

CCTA Contraindicated: CCTA is contraindicated in patients with a history of allergy to iodinated contrast medium Relatively contraindicated in diabetes and a serum creatinine concentration above 2.0 mg/dL Meijboom et. al ;Diagnostic accuracy of 64-slice computed tomography coronary angiography: a prospective, multicenter, multivendor study. J Am Coll Cardiol. 2008;52(25):2135

Why CCTA? ROMICAT study (Rule Out Myocardial Infarction using Computer Assisted Tomography) excellent NPV for plaque or stenosis, 100% and 98% respectively Sensitivity for a stenosis of more than 50% was only 77% US based ACCURACY trial: Multi center: 230 (94 %) of 245 enrolled subjects Sensitivity 95% and Specificity 83% Specificity fell to 53% with higher calcium burden ( Calcium scores of >400) An Agatston CACS of 1 to 99 identifies a mild amount of plaque burden, 100 to 399 is moderate, >400 is high, and >1000 is severely elevated. Meijboom et. al ;Diagnostic accuracy of 64-slice computed tomography coronary angiography: a prospective, multicenter, multivendor study. J Am Coll Cardiol. 2008;52(25):2135

Why CCTA? International CORE 64 study: 291 (72 %) of 405 enrolled patients were eligible for analysis since they had calcium scores of ≤600 Sensitivity 85% specificity 90% CCTA has shown its ability to effectively rule out obstructive and non-obstructive CAD with an exceptionally high negative predictive value 95 to 100 % Meijboom et. al ;Diagnostic accuracy of 64-slice computed tomography coronary angiography: a prospective, multicenter, multivendor study. J Am Coll Cardiol. 2008;52(25):2135

AHA Guidelines and CCTA JACC Vol. 63, No. 4, 2014 February 4, 2014:380–406 JACC Vol. 63, No. 4, 2014 February 4, 2014:380–406

CCTA Before Non-coronary Cardiac Surgery  The ability of 64-slice CCTA to exclude the need for concomitant CABG in patients undergoing cardiac surgery has been evaluated in a few single center studies These have demonstrated high sensitivity for detecting significant coronary artery disease 70 patients referred for cardiac valve surgery the prevalence of significant coronary artery disease The sensitivity of CCTA was 100 % and specificity was 92% 55 relatively young patients referred for valve replacement for aortic stenosis the prevalence of significant CAD was 20 percent % Sensitivity 100%, Specificity 80% Meijboomet. Al;Pre-operative computed tomography coronary angiography to detect significant coronary artery disease in patients referred for cardiac valve surgery.J Am Coll Cardiol. 2006;48(8):1658. Gilard et. al;Accuracy of multislice computed tomography in the preoperative assessment of coronary disease in patients with aortic valve stenosis; J Am Coll Cardiol. 2006;47(10):2020 Meijboomet. Al;Pre-operative computed tomography coronary angiography to detect significant coronary artery disease in patients referred for cardiac valve surgery.J Am Coll Cardiol. 2006;48(8):1658. Gilard et. al;Accuracy of multislice computed tomography in the preoperative assessment of coronary disease in patients with aortic valve stenosis; J Am Coll Cardiol. 2006;47(10):2020

CCTA Radiation Prospective gating : 'step-and-shoot' approach has decreased radiation exposure Scanner is turned on only during the part of the cardiac cycle when we know the heart will be still  radiation dose  Compared with retrospective gating ( where the scanner is on throughout the cardiac cycle) Recent study 2013 : 11,901 patients who received CCTA scans at 15 hospitals Analyzed the data between two groups I (July 2008-June 2009- older tech- retrospective gating) II (July 2009-April 2011 – “Step and Shoot Protocol” ) Results: Radiation dose decreased by 31 % between groups I & II No difference in scan quality The median effective radiation dose was 4.9 mSv for S & S

3D Reconstruction

Short axis view- Level of the Aortic Valve

Level of the Left Atrium

Example of severe stenosis and calcification Within the LAD

RCA

Cirx

CMR for Coronaries Data are not sufficient to support clinical for the routine identification of coronary artery stenosis in patients with chest pain or for the screening of patients with multiple risk factors for CAD However, the available literature supports a clinical role for CMRI in the assessment of congenital coronary anomalies and coronary artery aneurysms Moshage WE, Achenbach S, Seese B, Bachmann K, Kirchgeorg M;coronary artery stenoses: three-dimensional imaging with electrocardiographically triggered, contrast agent-enhanced, electron-beam CT.Radiology. 1995;196(3):707

CCTA vs CMRI Free breathing targeted 3D k-space gradient echo sequence with a 1.5 Tesla system Multicenter study of 109 patients in whom 636 (84 percent) of 759 proximal and middle coronary segments could be imaged with diagnostic image quality Multislice CCTA had significantly higher sensitivity 85% vs 72% with CMRI and specificity 95% vs 87% Moshage WE, Achenbach S, Seese B, Bachmann K, Kirchgeorg M;coronary artery stenoses: three-dimensional imaging with electrocardiographically triggered, contrast agent-enhanced, electron-beam CT.Radiology. 1995;196(3):707

Non Ischemic HF Echocardiogram is still the first line choice Valvular disease Cardiac tumors Pericardial disease Congenital Heart Disease Diastolic dysfunction CMR /Cardiac CT can assist in further imaging and details the factors above: Pericardial disease and cardiac tumors Diastolic Dysfunction ( detailed morphological changes on the LA/LV hypertrophy) Provides further tissue characterization (Arrhythmogenic RV CM) Infiltration/fibrosis ( T1) / inflammation ( T2 )

CMR eurheartj.oxfordjournals.org

Key Points  CCTA and CMRI are rapidly evolving technologies for the noninvasive visualization of the native coronary arteries for ischemia and non ischemic diagosis Current limitations are likely to be lessened with future improvements in technology The broader applicability of CCTA and CMRI results from research centers has not generally been established Local practice considerations, such as level of expertise, quality of the technology, and availability and quality of alternative diagnostic strategies, may influence decision- making

KEY POINTS In patients with no signs or symptoms suggestive of CAD, neither CCTA nor CMRI should be used to screen for coronary disease Noninvasive coronary angiography is reasonable for symptomatic patients who are: Intermediate risk for CAD after initial risk stratification ECG uninterpretable for ischemic changes (baseline ST segment abnormalities, LBBB) Patients who are unable to exercise Patients with equivocal stress test results Diagnostic accuracy currently favors CCTA over CMRI for these patients

KEY POINTS In patients with known or suspected congenital or acquired coronary anomalies, it is suggested to use CCTA or CMRI CMRI is preferred in younger patients, given concerns about potential long-term effects of radiation associated with CCTA In patients with CABG in whom it is not possible to selectively engage clinical important grafts during invasive angiography, we suggest CCTA or CMRI for evaluation of coronary artery bypass graft patency In patients with contraindications to beta blockers or iodinated contrast, CMRI is preferred to CCTA

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