Coronary artery disease

Background

Risk Factors

• Modifiable: tobacco use, dyslipidemia, diabetes mellitus, hypertension, chronic kidney disease, physical inactivity, diet, obesity, metabolic syndrome, depression
• Non-modifiable: age, sex, family history of premature cardiovascular disease, ethnic origin

Investigations

• Fasting lipids and HbA1c, to assess cardiovascular risk and guide risk reduction treatment
• Stress test: exercise or persantine/dobutamine; ECG or echo or nuclear (mibi); see below
  • Nuclear perfusion scan (mibi) or stress echo, for risk stratification and identification of reversible perfusion defects
• Angiography, for direct coronary visualization and diagnosis, and possible angioplasty
  • Done for high risk features on stress testing

Stress Test

graph LR;
LBBB_etc[LBBB or V-paced] --yes--> mibi[persantine mibi]
LBBB_etc --no--> exercise[can exercise?]
exercise --yes--> normal_ecg[ECG normal]
exercise --no--> either[persantine mibi or dobutamine echo]
normal_ecg --yes--> exercise_ecg[exercise ECG]
normal_ecg --no--> exercise_either[exercise mibi or echo]

Management

• Medical management
  • Secondary prevention
    • Antiplatelet
      • ASA, with a PPI if history of GI bleeding
      • If ASA allergy, use clopidogrel
    • BP control, preferentially with ACE inhibitor or ARB
    • If heart failure, ACE inhibitor or ARB
    • Statin regardless of cholesterol
  • Anti-anginal medications
    • Beta blockers, which is the only one with possible mortality benefit
    • Calcium channel blockers
    • Nitrates
• Cardiac rehab
• Procedures
  • Angioplasty (percutaneous intervention [PCI])
    • Requires dual antiplatelet therapy (DAPT) for up to 1 year (for drug-eluting stents)
  • Coronary artery bypass surgery (CABG)
    • Better for multivessel disease, diabetics

ABCDE

• Antiplatelets and ACEi/ARB
• Beta blockers and BP
• Cholesterol, cigarettes, and cease hormone-replacement therapy
• Diet and diabetes
• Exercise and education

Further Reading

• Canadian Cardiovascular Society Guidelines for the Diagnosis and Management of Stable Ischemic Heart Disease. Can J Cardiol. 2014;30(8):837-849. doi: https://doi.org/10.1016/j.cjca.2014.05.013