Coronary Arteries

Introduction to coronary arteries, tests, and treatments, with brief look at peripheral arterial disease.

1. Coronary Arteries The Basics and Beyond

2. Function of coronary arteries : delivery of oxygenated blood to the heart muscle (myocardium) The VERY Basics How-to-draw-cartoons-online.com

3. Left coronary artery : arises from the left coronary sinus/cusp of the Aortic valve Left main artery branches into: LAD - Left Anterior Descending CX - Circumflex Right coronary artery : arises from the right coronary sinus/cusp of the Aortic valve Main Branches

4. Coronary arteries lie on top of the myocardium ( epicardial ) and follow the Atrioventricular (AV) groove and the Interventricular (IV) groove CX courses along AV groove LAD and distal RCA follow IV groove Basics, cont

5. Cvphysiology.com

6. LAD : diagonals and septals CX : obtuse marginals , occasionally Posterior descending artery (PDA) RCA : acute marginals , Posterior lateral artery (PLA), and PDA Ramus intermedius : arises between LAD and CX in 5%-10% of population Major Branches

7. A person can be “right dominant”, “left dominant”, or “co-dominant”. This depends on which artery (or arteries) give rise to the PDA and PLA, which run along the posterior side of the heart. Coronary Dominance

8. Right Dominant The PDA branch arises from the RCA (60%-70% of population)

9. Left Dominant The PDA arises from the LCA (10%-15% of population)

10. RCA gives rise to the PDA and then ends, while the CX supplies the PLA branches CX may also supply a left PDA that runs parallel to the right PDA Co-Dominant

11. As with all structures in the human body, WEIRD stuff can happen! A few examples: CX originates with RCA from right sinus LM from right sinus RCA from left sinus Separate originations ( ostia ) for all three All three arteries from one ostia Variations and Anomalies

12. Coronary aneurysms Fistulas- abnormal communication with venous system Anomalous origin of LCA from Pulmonary Artery (defect that can have a mortality rate of 90% in first year of life, due to MI or MR leading to CHF) Anomalies

13. Adventitia - outermost, connective tissue covering the vessel Media - smooth muscle cells Spasm- contraction of cells causing disturbance of blood flow (caused by numerous factors: caffeine or stimulant induced, catheter induced) Intima - innermost, single layer of cells Anatomy of an Artery

14. Ncbi.nlm.nih.gov

15. LAD supplies : most of septum, anterior/lateral/apical LV , anterolateral pap muscle CX supplies : LA , posterior/lateral LV , anterolateral pap muscle, SA node (45%), AV node (10%), septum, His bundle, posterior pap muscle, inferoposterior LV RCA supplies : SA node (55%), RA , AV node (90%), septum, His bundle, posterior pap muscle, inferoposterior LV Myocardial Blood Supply

16. Myocardial Blood Supply Med.yale.edu

17. Coronary Arteries perfuse in diastole (this is part of the theory behind the IABP) Coronary sinus collects used blood from the mycardium to send to lungs for re-oxygenation Coronary bridging = compression of a coronary artery by the myocardium during systole Usually benign, but can occasionally result in MI or even death (most common with LAD) Hemodynamics

18. Several medications are injected to elicit vasodilation in the arteries during catheterization, such as diltiazem , verapamil , adenosine, nitroglycerine, and nipride IIbIIIa Inhibitors ( abciximab , eptifibitide ) are also directly injected in coronary arteries with apparent thrombus Pharmacology

19. CAD and Atherosclerosis : What does this mean, exactly? Build-up of fatty substances, cholesterol, cellular waste products, and calcium within the intima of an artery With or without symptoms Coronary Artery Disease

20. Pathophysiology of CAD

21. Rupture of fibrous cap Platelets rush in to fix the vessel Clot forms Blood flow obstructed Damage/death of myocardium Pathophysiology of Acute MI

22. Many tests and screening tools are available to help detect CAD Can be invasive or non-invasive Can be performed in MD’s office or hospital, depending on type of test Diagnostic Testing Methods

23. Treadmill - assesses coronary blood flow by ECG, blood pressure, and signs/symptoms during exercise Stress Tests

24. Stress Echocardiogram -compares LV wall motion at rest and under stress Used for low-moderate risk patients and younger patients where there may be structural/valvular/congenital causes of symptoms Stress Tests Johnson.com

25. Perfusion scan - compares blood flow at rest and under stress by imaging the myocardium after a radioactive tracer is injected Stress Tests Bocacardiology.com

26. Echocardiogram - assesses structural, valvular, and congenital causes of heart disease Diagnostic Testing Brighamandwomens.org

27. Cardiac MRI - useful for diagnosis of structural disease ( cardiomyopathy , masses) with or without contrast Gold standard for congenital heart disease Diagnostic Testing

28. Cardiac Computed Tomography ( CT )- evaluates coronary arteries as well as LV function, anatomy, and calcification (calcium score) Diagnostic Testing Imagingeconomics.com

29. Cardiac CT Images 64ctscan.com Csmc.edu

30. Coronary Angiography - used for positive and indeterminate stress tests, assessment of bypass grafts Also for patients with known history of CAD Gold standard for coronary evaluation Diagnostic Testing Circulation.or.kr

31. IVUS - small ultrasound catheter is inserted in the coronary artery to image the vessel and assess plaque Can differentiate between fibrous and calcified plaque Virtual histology Diagnostic Testing Intravascular Ultrasound Ptca.org

32. Technically : the ratio of blood flow in a stenotic artery to normal flow Essentially : a stress test on a specific artery Flow is measured by a special guidewire , using flow measurements beyond the lesion and comparing them with flow before the lesion IV infusion of Adenosine is used to increase HR Ratio is calculated from a 2-3 minute period Normal value = 1.0 Abnormal value = <0.75 Diagnostic Testing Fractional Flow Reserve (FFR)

33. Treatment of CAD Medical treatment - managing the patient’s medications to help alleviate symptoms Percutaneous Coronary Intervention ( PCI )- used in various situations, from single lesions to complex, high-risk multi vessel disease

34. Nhlbi.nih.gov

35. Treatment of CAD Coronary Artery Bypass Grafting - most often used for severe multi vessel disease and diabetic patients Beaumonthospitals.com

36. We’ve come a long way from the first accidental coronary angiogram in 1958… Diagnosis and treatments continue to evolve Coronary Arteries Summary

37. Peripheral Arterial Disease (PAD) Same arterial anatomy and disease process, but most patients (with exception of CVA) tend to wait much longer to seek treatment May mimic arthritis, neuropathy Symptoms attributed to “old age” What about Peripheral Vascular Disease?

38. Claudication - leg pain with walking that resolves at rest Decreased temperature of extremity Non-healing wounds Symptoms of LE PAD

39. Sudden numbness or weakness , especially on one side Sudden confusion , trouble speaking Sudden trouble seeing in one or both eyes Sudden dizziness , loss of balance and coordination Sudden severe headache Symptoms of CVA

40. Ultrasound/Doppler studies MRI/MRA CT/CTA Angiography Diagnostic Testing for PAD

41. Medications Percutaneous Transluminal Angioplasty (PTA) with or without stent placement Atherectomy Bypass surgery Treatment of PAD

42. Interventions done for high-risk, asymptomatic or symptomatic patients (depends on clinical study enrollment) All patients must be enrolled in a research study to receive a stent Typical criteria: asymptomatic with >80% stenosis by ultrasound, or symptomatic with >50% stenosis and at least one high-risk factor, such as age>80 years, CHF, severe COPD, previous CEA with restenosis , previous radiation therapy or neck surgery, lesion location Carotids

43. Cleveland Clinic Heart and Vascular Institute

44. Code Stroke An Interdisciplinary effort to get treatment started for stroke victims ASAP Emcompasses : ED assessment, activation of Code Stroke protocol, Neurology consults, CT scans, Interventional Cardiology consults, thrombolytic treatment if indicated, invasive intervention if indicated

45. Renals Interventions performed for poorly controlled hypertension or poor renal function Rivascularinstitute.com

46. Interventions performed for claudication , critical limb ischemia (non healing wounds), and limb salvage Lower Extremity

47. Radiologyrsnajnls.org

48. PAD Basically, if we can get a catheter to an artery, we can take a picture and potentially intervene! Mesenterics Subclavians ETC…

49. Fast growing segment of cardiac cath lab procedures Percutaneous treatments are constantly being developed PAD Summary

50. Cvphysiology.com Heartsite.com NEJM, Vol. 360 No.3 Ncbi.nlm.nih.gov Encyclopedia Brittanica Med.yale.edu Johnson.com Bocacardiology.com Brighamandwomens.org Nature Publishing Group Emedicine.medscape.com Sources

51. 64ctscan.com Csmc.edu Circulation.or.kr Ptca.org Beaumonthospitals.com Nhlbi.nih.gov Cleveland Clinic Heart and Vascular Institute Rivascularinstitute.com Radiologyrsnajnls.org Imagingeconomics.com How-to-draw-cartoons-online.com Sources