Using Coronary Artery Calcium Score in the Quest for Cardiac Health Robert J. Hage, D.O.
Heart disease is the leading cause of death in the United States in both men and women. About 610,000 people die of heart disease in the United States every year that s 1 in every 4 deaths. Coronary heart disease is the most common type of heart disease, killing over 370,000 people annually. Every year about 735,000 Americans have a heart attack. Of these, 525,000 are a first heart attack and 210,000 happen in people who have already had a heart attack. 01 / Write Your Title Here 02 / Write Your Title Here
Atherosclerosis begins with damage to the endothelium, a thin layer of cells that line the arteries. The body responds to the damage with the formation of plaque, a combination of low density lipoproteins, White blood cells, and other substances. This leads to arterial stiffening, narrowing, and thrombolysis.
Risk Factors High blood pressure High blood cholesterol Diabetes and prediabetes Smoking Being overweight or obese Being physically inactive Having a family history of early heart disease Having a history of preeclampsia during pregnancy Unhealthy diet Age These have been known for decades, but heart diseas remains rampant.
How To Live a Healthy Lifestyle? A healthy diet leads to a lower Body Mass Index. And maintaining a normal BP is important in limiting the progression of atherosclerosis
About Our CT Study A low dose multislice CT scanner can perform a cardiac scan in 5-10 minutes.
Radiation Dose Comparisons Source of Radiation Chest x-ray Mammogram Effective Radiation Dose 0.05 msv 0.7 msv Source: Harvard Heart Letter, Published July 2012 Calcium scoring test Annual Natural exposure 3 msv Cardiac catheterization 7 msv Chest CT 10 msv Coronary CT angiography 3-14 msv Radionuclide sestamibi stress test 10-12 msv Radionuclide dual isotope myocardial perfusion imaging 25 msv
Risk: Incidental Findings CT's can demonstrate incidental findings, which can lead to further tests and radiation exposure, frequently with a benign diagnosis. In this case, however, the patient had a CT-guided needle biopsy, which showed small cell carcinoma.
CAD Pathology Soft plaque appears as blood on the CT scan and is not visualized. The advanced calcified plaque is well seen and can be quantified.
Coronary Arteries Cardiac gating allows finely detailed views of many of the anatomical structures of the heart. 01 / Write Your Title Here 02 / Write Your Title Here
CT Scan Agatston The semiautomatic Agatston scoring software calculates the product of the calcified plaque area within a CT slice and incorporates a plaque-specific density factor of 1, 2, 3, or 4. The density factor reflects increasing categories of Hounsfield units (Hu). Thus, the Agatston score is weighted upward for greater CAC density..
Agatston Score Table 01 / Write Your Title Here 02 / Write Your Title Here
Coronary Artery Calcification Slide Patient A
Coronary Artery Calcification Slide Patient B
Coronary Artery Calcification Slide Patient C 61 year old male PM Hx: Hypertension, Hypercholesterolemia 15 yr. smoking history, quit in 2001 Fam Hx: Coronary artery disease 2017 Agatston score = 1,205.9 2002 Agatson score = 15.6
Framingham Cardiac Risk Score Standard Framingham Cardiovascular Disease Risk Prediction Using BMI Gender Age Systolic BP Treatment for HTN? Current smoker? Diabetes mellitus? Body Mass Index(BMI) Using Lipids Gender Age Systolic BP Treatment for HTN? Current smoker? Diabetes mellitus? HDL Total Cholesterol
Framingham Risk Classification Algorithm Risk Classification Algorithm Used in the ATP-III 2004 Update Risk Category High Risk Moderately high risk Moderate risk Lower risk Definition CHD or CHD risk equivalent or >2 risk factors and 10-y predicted risk of >20% >2 Risk factors and 10-y predicted risk of 10% to 20% >2 Risk factors and 10-y predicted risk of <10% 0-1 Risk factor
Framingham Risk Score Graph Source:
Arterial Age as a Function of Coronary Artery Calcium (From themulti-ethnic Study of Atherosclerosis [MESA]) Contributors: Robyn L. McClelland, PhDa, Khurram Nasir, MD MPHb, Matthew Budoff, MDc, Roger S. Blumenthal, MDd, and Richard A. Kronmal, PhDa Table 1: Estimated Arterial Age and 95% Confidence Intervals by Coronary Arterial Age CA CA in Years Arterial Age in Years (95% CI) C C (95% CI) 0 39 (32 46) 100 73 (71 74) 10 56 (53 60) 200 78 (75 80) 20 61 (59 63) 300 80 (78 83) 30 64 (62 66) 400 83 (79 86) 40 66 (65 67) 500 84 (80 88) 50 68 (67 69) 750 87 (83 92) 100 60 69 (68 70) 0 150 70 70 (69 71) 0 200 80 71 (70 72) 0 250 90 72 (71 73) 0 Position here Position here 89 (84 94) 92 (87 98) 94 (88 100) 96 (89 102) osition here Position here Estimated Arterial Age and 95% Confidence Bands by Coronary Artery Calcium The estimated arterial age with 95% confidence bands is displayed for each CAC score. CAC is displayed on the log scale, but labeled in original units for ease of use. A person with a CAC score of 10 Agatston units has an estimated arterial age of approximately 56, while a CAC score of 400 yields an arterial age of 83. Discussion Point Using arterial age when calculating the Framingham risk is more predictive of short-term incident coronary events. Also, it gives patients an understandable interpretation of their CAC score.
Coronary Artery Calcium Testing Among Statin Candidates Viewpoint Approximately 45 million American adults who have been diagnosed with cardiovascular disease are recommended to be considered for statin therapy, based on the ACC/AHA recommendations for individuals with 10 year ASVD risks of 7.5% and 5% to 7.5%. Of these 45 million patients, nearly 50% will have a CAC of zero. The Kaplan-Meier curves demonstrates significantly reduced estimated cardiac events in this group. This supports reducing their risk and possibly obviating the need for statin therapy.
Discrimination of MESA 01 / Write Your Title Here 02 / Write Your Title Here McClelland, R, et. al, Journal of American College of Cardiology, Vol 66, Nov 15, 2015
Follow-up cardiac scan A follow-up Cardiac Scan was performed after approximately 3 years. The progression is visually striking. Markedly advanced atherosclerotic calcifications are noted in the left anterior descending 01 coronary / Write Your artery. Title Here The total Agatston score has increased 02 / Write from Your 470 Title to a Here current value of 821.
Follow-up cardiac scan # 2 These images demonstrate the significant calcified atherosclerotic progression in the proximal circumflex artery. 01 / Write Your Title Here 02 / Write Your Title Here
After 3 years, the patient s Agatston score increased from 36.5 to 67.0 with mild plaque burden.
The patient complained of chest pain for two weeks. His Agatston score was 2,442. He was sent to the emergency room for evaluation.
The asymptomatic patient had a score of 1,583, which placed her in the 96th percentile.