Heart Disease

• All causes of sudden unexpected death: The first indication of heart disease is actual sudden death in 150,000 Americans each year! Of all unexpected deaths, many causes are "heart attacks" and other heart-related deaths. All sudden death causes

• American College of Cardiology: their site has a large number of on-line documents about risk and treatments, etc.; in that website they are called "Clinical Statements/Guidelines"

• Global risk assessment: you can self test with this on-line calculator tool, the "Framingham CHD risk stratification risk score" (FRS) assessment.

• Risk factors (and lab tests) for cardiac disease: conventional wisdom has it that there are 4 major, modifiable, traditional risk factors for MI: smoking, diabetes mellitus, high blood pressure (hypertension), and elevated blood cholesterol (hypercholesterolemia)⁴. Among patients with coronary heart disease (CHD), 80-90% will have one or more those 4 risk factors⁵.

  • Genetic predisposition (Do "heart attacks" run in your blood relatives...in family genes? Has anyone dropped dead of a "heart attack" below age 50?): a heavy percentage of risk is here

  • Lab tests related to heart attack risk evaluation

  • Imaging tests:

    • Invasive: coronary arteriogram (visualize artery constrictions)

    • Noninvasive:

      1. Physiological: nuclear medicine stress test

      2. Visualize pathological arteries: see below

      3. resting sestamibi perfusion scan

  • Excesses or Deficiencies (too little exercise...poor heart fitness) of the below items for "prevention"
• Prevention:
  • Regular exercise: are you exercising enough? [cardiopulmonary fitness self tests]
  • Proper diet:
    • normal
    • supplements:
      1. folic acid: helps prevent elevation of total homocysteine (tHcy) (if elevated, take 1 mg folic acid per day)
      2. vitamin E 400-800 mg./day: the Cambridge Heart Antioxidant Study (CHAOS) showed a 77%¹ reduction in AMIs  with this intake (other antioxidants are selenium, vitamin C, and beta-carotene)
  • Proper lifestyle habits: quit smoking! 
  • Maintain proper weight: calculate with Medical College of Wisconsin's on-line calculator and get your BMI and see if you are "overweight" (BMI 25-29) or even "obese" (BMI 30 or higher). Goal is less than 25.
  • Control heart-injuring disease: 
    • have a lipid profile done under optimal conditions (no illness, change of activity level or change of diet in past 3 weeks; nothing to eat after 10 pm...a 9-12 hour fast...the night before the specimen is drawn) and address any abnormalities. Goal is total cholesterol no higher than 200. Then calculate risk with the Medical College of Wisconsin's on-line calculator and/or the Pfizer on-line calculator and/or the NIH on-line calculator. Check the NIH's May 2001 3rd report (ATP III) of the NCEP Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults. Consider medications to lower bad cholesterol (statins) or increase good cholesterol (niacins). Since inflammation is thought to be a key factor in the coronary artery lesions, an aspirin a day (especially if hs-CRP indicates an increased risk) is thought to be advantageous. 
    • check fasting blood glucose and, if elevated, address the possibility that you are diabetic; and, if diabetic, be diligent about managing and controlling the disease.
    • starting at one of the pharmacies or chain stores, check your blood pressure on their machine and, if elevated, address the possibility that you are hypertensive. And, if so, be diligent about management and treatment. Goal is systolic no higher than 120 and diastolic no higher than 80.

Diagnosis of silent disease and/or acute MI:

• History & physical for both typical: (crushing chest pain or tightness on, or shortly after, exertion; & diaphoresis [sweating]) or atypical presentations...myocardial infarction re-defined. 

• Electrocardiogram (EKG or ECG): first-line ER test or non-emergency screening test searching for electrical abnormalities possibly reflecting cardiovascular abnormalities (only about 50% sensitive for cardiovascular abnormalities).

• "Acute MI profile" emergency department lab tests for LMC-ER: [2001 letter] it is crucial to fix the time of onset of the episode in order to properly interpret the lab test profile [2002 update letter]; informative  lab letters, above.

• Stress tests:

  • treadmill: EKG test while you walk on a treadmill at certain speeds and inclines; looks for stress-related electrical reflections of cardiovascular abnormalities; can also have false positive and false negative results.

  • treadmill stress followed by echocardiogram: the "echo" component of this test searches for heart muscle dilation and contraction abnormalities in the walls of the 4 chambers of the heart which might reflect cardiovascular abnormalities.

  • radionuclide stress test: a "nuclear medicine" stress test; takes about a half day; radioactive isotope is injected in your vein; the treadmill stress exposes old hear scar, unstable heart scars, and areas in heart muscle which get too little blood when under stress. Areas are revealed as metabolic "cold spots".

• Coronary arteriography: a catheter is inserted in the groin artery and guided into the heart where die is squirted into the two coronary artery entries; about 33% of cases result in insertion of an average of just over one stent per patient; there is a low false negative diagnostic rate (failure to see an occluding plaque. However, 6% of men and 10% of women with EKG ST-segment elevation have normal or near-normal angiograms/arteriograms⁸. Of cases of unstable angina and normal or near-normal arteriograms, there is a 2% risk of death in the next 30 days⁸! And, some 20% of troponin negative, unstable angina non-ST-segment-elevated acute coronary syndrome (ACS) patients visiting an ER with chest pain have a cardiac event within the following six months.

• Coronary intraluminal ultrasound: similar to arteriography but use an ultrasound probe rather than dye.

• (fast spin) spiral CT &/or (electron beam tomography) EBT: detects coronary calcification and "scores" it...some extend the test to "whole body". Arterial calcification means damaged arteries:

  • such as S. C. Heart's "HeartSense" (Columbia, S. C.)

  • Lexington Medical Center's "HeartReach" (Lexington, S. C.) EBT for coronary artery calcium ("CAC") scoring; see "Chest X-ray" web site for techniques, anatomy, and risk calculations for calcium and other factors

  • Ameriscan

  • HealthScreen America

• Mammography: vascular calcification of breast arteries seen on mammograms is associated with an increased incidence of CAD, & subareolar "whiteout" density is a reflector of chronic CHF.

• The Heart Forum at the Cleveland Clinic:ask your questions of their cardiologists & view archived questions.

• Treatments:

  • Medical (medication & cardiac "rehab"):

    • statins

    • bile acid sequestrants

    • angiotensin converting enzyme (ACE) inhibitors

    • beta blockers

    • antithrombotics

      1. fibrinolytics

      2. platelet glycoprotein IIb/IIIa inhibitors

      3. clopidogrel

    • anti-clot-propagation

      1. aspirin

      2. infusion of antibodies (such as anti-platelet-membrane glycoprotein IIb/IIIa receptor Ab post stent placement)

  • Open surgical: open-heart bypass surgery
  • Invasive transvascular interventional:
    • coronary angioplasty ("Roto Rooter" or balloon angioplasty the occluded artery)
    • place a stent to hold open the tight segment of artery
    • radiate the stent area at the time of placement (adds about 10 minutes to the angioplasty and stent placement and has no separate side effects)...radiation supposed prevent the body from filling in the stent with tissue (another option is use of stents impregnated with growth retarding chemicals...bypassing need for radiation)
    • for chronic calcified occlusions, occlusions of stents, or occlusions in vessels that are otherwise too hard, the excimer laser [sites] uses a cool beam of UV light to "vaporize" plaque rather than burn it away.
  • Dietary: search the internet for cardio-protective diet.
  • External mechanical:
    • enhanced external counterpulsation (EECP) [one source]

References:

1. CAP Today, "Picking New Winners for Cardiac Risk", interviewing H. K. Naito, Santica M. Marcovina, Jerome Cohen, Richard Cannon, Paul Ridker, Nader Rifai, November 2001.

2. JAMA editorial, "Inflammatory Markers in Coronary Artery Disease...", Vorchheimer DA and Fuster V, 286(17):2154, 7 Nov. 2001.

3. JAMA editorial, about EBT & CAC detection, Greenland P, 289(17):2270, 7 May 2003.

4. Major Risk Factors for Cardiovascular Disease: Debunking the "Only 50%" Myth, Canto JG & Iskandrian AE, JAMA 290(7):947-949, 20 August 2003.

5. Prevalence of Conventional risk Factors in Patients With CHD, Khot UN, et. al., JAMA 290(7):898-904, 20 August 2003.

6. Major Risk Factors as Antecedents of Fatal & Nonfatal Coronary Heart Disease Events, Greenland P, et. al., JAMA 290(7):891-897, 20 August 2003.

7. Emerging Risk Factors for Atherosclerotic Vascular Disease: A Critical Review of the Evidence, Hackam DG & Anand SS, JAMA 290(7):932-940, 20 August 2003.

8. Angina With "Normal" Coronary Arteries, Bugiardini R. & Merz CNB, JAMA 293(4):477-484, 26 January 2005.

9. CAP Today, "Clearing a path for New Cardiac Markers", interviewing R. Christenson, Alan Maisel, Stanley Hazen, Ken Buechler, John Shaw, Jessie Shih, Robert Olsen, February 2005.

10. CAP Today, "Using markers for a head start on heart risk", Robert Christenson, PhD, Dec. 2007.

(posted Oct. 2001; latest addition 19 January 2008)