21st Annual Contemporary Therapeutic Issues in Cardiovascular Disease Noninvasive Evaluation of Coronary Artery Disease: Anatomical, Functional, Clinical May 5, 2018 Mark Hansen MD FRCPC Cardiologist, Schulich Heart Centre Assistant Professor, Department of Medicine University of Toronto
No Conflict or Disclosure
LEARNING OBJECTIVES To develop a greater understanding of the application of cardiac imaging modalities in the detection and management of coronary artery disease: stress echocardiography myocardial perfusion imaging coronary CT angiography
Coronary Artery Disease
Hansson G NEJM 2005;352:1685-1695 Libby P NEJM 2013;368:2004-2013
Libby P, Theroux P, Circulation 2005;111:23481-3488
When seeking an answer, begin with the right question
Detection vs. Management? Diagnosis vs. Prognosis? Anatomy vs. Function?
Case 49 year old male Phys. Ed. teacher Diminished exercise capacity?aging Positive family history of premature CAD BP 148/88 Glucose 5.4 Cholesterol 6.88, TG 4.92, HDL 1.28 GXT: 12min Bruce, 12.8METs, mild dyspnea, peak BP 210/73, 2mm horizontal ST depressions
Case 49 year old male Phys. Ed. teacher Diminished exercise capacity?aging Positive family history of premature CAD BP 148/88 Glucose 5.4 Cholesterol 6.88, TG 4.92, HDL 1.28 GXT: 12min Bruce, 12.8METs, mild dyspnea, peak BP 210/73, 2mm horizontal ST depressions What Now?
What Now? Reassurance? Medical therapy? Stress echocardiography? Myocardial perfusion imaging? CT coronary angiography? Invasive coronary angiography?
The Ischemic Cascade
The Ischemic Cascade
The Ischemic Cascade
The Ischemic Cascade
Will this information: change health behaviour? change management? Is this investigation: cost effective? worth the risk?
Case - cont. Referred for stress echocardiography
STRESS IMAGING Rest Stress Exercise Pharmacological
STRESS ECHO Rest Stress Exercise Dobutamine
STRESS ECHO Advantages Cheap No radiation Specific Disadvantages Operator-dependent Not very sensitive e.g. circumflex ischemia Special Considerations Extensive literature on pre-op evaluation (dobutamine) Poor images = poor accuracy Inadequate stress = nondiagnostic test Challenging when baseline wall motion abnormality
STRESS ECHO Ideal Patient Rule-in scenario Interpretable ECG Good image quality Capable of reaching max HR Normal baseline LV function (Serial follow-up) Ideal Lab Direct MD supervision Excellent equipment Excellent sonographer
Case - cont. Stress echocardiography: 12min Bruce, 12.8METs, mild dyspnea, 2mm horizontal ST depressions, normal left ventricular systolic function at rest and stress What Now?
Case - cont. Referred for myocardial perfusion imaging
MYOCARDIAL PERFUSION IMAGING Rest Stress Exercise Persantine Adenosine
MYOCARDIAL PERFUSION Advantages Sensitive Quantitative Less operator dependent IMAGING Disadvantages Expensive Radiation Less specific (Breast, diaphragm attenuation) Special Considerations Very extensive literature on prognosis Applicable to known CAD LBBB (pharmacological) Inadequate stress = nondiagnostic test
MYOCARDIAL PERFUSION IMAGING Ideal Patient Rule-out scenario Intermediate body habitus (Not serial follow-up) Ideal Lab Excellent equipment Excellent analysis Case correlation
Einstein A et al. Circulation 2007;116:1290-1305
Case - cont. Exercise myocardial perfusion scan: 12min Bruce, 12.8METs, mild dyspnea, 2mm horizontal ST depressions, normal myocardial scintigraphy, left ventricular volumes, and scintigraphy at rest and stress What Now?
Boiten H et al. J Nuc Card 2016
Case - cont. Referred for CT coronary angiography
CT CORONARY ANGIOGRAPHY
CT CORONARY ANGIOGRAPHY Advantages Excellent anatomical information Sensitive & specific Quantitative Less operator dependent Disadvantages Relatively expensive Radiation Contrast Does not provide functional information Special Considerations Heart rate-dependent Beta-blocker, NTG pre-treatment
CT CORONARY ANGIOGRAPHY Ideal Patient Bradycardia Rule-out scenario Not previous PCI Not extensive Ca++ (Not serial follow-up) Ideal Lab Excellent equipment Excellent analysis Case correlation
RANDOMIZED TRIALS IN CARDIOVASCULAR IMAGING CHALLENGES:?Study population Core lab vs. community / real life? Indirect association between imaging strategy and outcomes.?what endpoint Accuracy? Clinical outcomes? Patient-centred outcomes? Cost-effectiveness?
NEJM 2015;372(14)
PROMISE STUDY NEJM 2015;372(14)
Lancet 2015;385:9985:2383-2391
J Am Coll Cardiol Img 2011;4:740 51
J A C C : C A R D I O V A S C U L A R I M A G I N G V O L. 4, N O. 7, 2 0 1 1
J A C C : C A R D I O V A S C U L A R I M A G I N G V O L. 4, N O. 7, 2 0 1 1
Case - cont. Agatston (Coronary Artery Calcium) score: 0 No significant coronary arterial calcification in all three vessels. Minimal noncalcified plaque at the proximal D1 causing less than 30% narrowing of the lumen
Case - cont. Agatston (Coronary Artery Calcium) score: 0 No significant coronary arterial calcification in all three vessels. Minimal noncalcified plaque at the proximal D1 causing less than 30% narrowing of the lumen What Now?
What Now? Reassurance? Medical therapy? Repeat stress testing? Invasive coronary angiography?
What Now? Reassurance? Medical therapy? Repeat stress testing? Invasive coronary angiography? Advised to take ASA, statin, ACEinhibitor patient declined
6 weeks later
Conclusions GXT, Stress Echo, Myocardial Perfusion Imaging and CT coronary angiography are all reasonable initial diagnostic strategies in patients with suspected coronary artery disease. Choice should be informed by patient factors and local resources. Coronary risk can be estimated, but events are difficult to predict. Integration of all clinical data is necessary in formulating a treatment plan.
SUMMARY