Coronary artery disease

Heart like all the muscles in the body needs continuous blood supply to work and pump blood to all organs of the body effectively. These muscles of heart receive blood supply from coronary arteries.

Coronary artery disease is the narrowing or blockage of coronary arteries, most commonly caused by atherosclerosis (cholesterol and fatty deposits called plaques on the inner wall of the arteries), that makes the artery wall rigid. The heart muscles become starved of oxygen and nutrients causing chest pain called angina. If blood supply to a portion of heart is cut off completely, it may lead to injury to this heart muscle causing heart attack.

It develops over years and ma be diagnosable only with significant blockage of coronary arteries or heart attack. But it can be prevented with healthy lifestyle changes.

Risk factors:

Most common and leading cause of death in the US.

1. Men have a higher risk of heart attack than women do and at a younger age than women. Risk for women increases after menopausal age.
2. Age - Higher risk as age progresses, especially after 65 years of age-damaged and narrowed arteries.
3. Family history of heart disease.
4. Race - Americans have higher risk due to obesity, diabetes.
5. High cholesterol in blood - High LDL (>100mg/dl) and low HDL (<40mg/dl)-for atherosclerosis.
6. Hypertension - More than 140/90 mm Hg. It causes hardening and thickening of artery walls and narrows the arteries.
7. Uncontrolled Diabetes - HbA1c >7
8. Sedentary life style.
9. Alcohol consumption.
10. Cigarette smoking.
11. Unhealthy diet-foods with saturated fat, trans fat, salt and sugar.
12. Overweight/obesity - (waist measurement above navel more than 35inch in women, over 40inch in men)
13. Stress, anxiety. 

Symptoms:

Symptoms develop when the plaque continues to grow in the coronary arteries. It develops when the heart doesn’t get enough blood to work effectively and if need exceeds demand.

1. Middle or left sided chest pain (angina) - Felt as squeeze, pressure, tightness of chest, numbness, ache, etc. This is usually triggered by stress, physical exertion and subsides in a few minutes on taking rest or with medication. It can also be felt in shoulder, arms, neck, jaw, back.
2. Shortness of breath, nausea, dizziness, palpitations, sweating, fatigue.
3. Unstable angina - Develops at rest and lasts long. It doesn’t subside with medications and may progress to heart attack.
4. Heart attack - Caused by a completely blocked coronary artery. It can occur when plaque ruptures, that lead of accumulation of inflammatory cells, lipoproteins, fat, platelets, etc. increasing the size of plaque. The chest pain may radiate to left arm, shoulder, back, associated with nausea, dizziness, sweating, fatigue, palpitations, etc.

Approach to chest pain:

• History and physical examination.
• Chest Xray
• Electrocardiogram (ECG)
• Echocardiogram (ECHO)
• Exercise stress test
• Cardiac catheterization - Coronary angiogram
• For estimation on extent of block, its effect on heart and for planning treatment options.

Differential diagnosis of chest pain:

1. Stable angina.
2. Unstable angina.
3. Prinzmetal’s angina - Variant angina, angina inversa. At rest due to coronary artery spasm. Subsides with medications. Risk factors are exposure to cold, stress, smoking, etc.
4. Myocardial infarction - Due to cell death in heart muscles.
5. STEMI, NSTEMI (ECG normal).
6. Pulmonary embolism - Symptoms of DVT (pedal edema, calf pain, tenderness and erythema), hemoptysi, dyspnea, palpitation.
7. Heartburn - gastritis, GERD.
8. Pneumonia - high grade fever, wet cough, tachypnea (>25 breaths/min), etc. Dull on percussion.
9. Muscle pain/cramp - dehydration, physical exertion.
10. Costochondritis - chest tenderness, painful deep breaths.
11. Anxiety, panic disorder. Heart like all the muscles in the body need continuous blood supply to work and pump blood to all organs of the body effectively. These muscles of heart receive blood supply from coronary arteries.

References

• https://my.clevelandclinic.org/health/diseases/16898-coronary-artery-disease
• https://www.mayoclinic.org/diseases-conditions/coronary-artery-disease/symptoms-causes/syc-20350613
• https://www.webmd.com/heart-disease/guide/heart-disease-coronary-artery-disease#1
• https://www.cdc.gov/heartdisease/coronary_ad.htm
• https://www.heart.org/en/health-topics/consumer-healthcare/what-is-cardiovascular-disease/coronary-artery-disease
• https://www.aafp.org/afp/2005/1115/p2012.html

List of meds:

1. Ranitidine.
2. Pantoprazole.

ICD coding:

1. Stable angina - 120.9
2. Unstable angina - 120.0
3. Variant angina - 120.1
4. Myocardial infarction - 125.2 (old MI)
5. NSTEMI, STEMI
6. Pulmonary embolism - 126
7. Gastritis (K29.0), GERD (K21)
8. Pneumonia.
9. Muscle pain (M79.1)
10. Costochondritis - M94.0