Mastering Heart Health: Your Complete Guide to Prevention, Part 3 (Labs and Imaging)

Hello and welcome to Part 3 of our email series on Heart Disease!

In this post, we are going to delve into the topics most of you are waiting for — lab work and imaging.  In the last two emails, I hope I have driven home the point that heart disease is a universal health challenge that we all must address in our daily lives. We cannot turn a blind eye to our risk factors and simply hope for the best. Being proactive about your heart (and your brain) will set you up for happier, healthier, more vibrant future.  

I love getting labs and interpreting them for my patients. Few things at work bring me more joy than a panel of labs and a patient genuinely interested in what they mean and what they can do about them. And this is especially true about reviewing labs related to our heart. Lab work and imaging are powerful tools to help you understand not only exactly how you have been doing in regards to heart health but also provides tangible metrics that we can track over time to demonstrate your efforts to improve them. Before we get into the specifics, it’s important for you to know that this is not personal medical advice — any lab or imaging test must be ordered and interpreted in conjunction with your personal health risk factors.

My Must-have Labs for Heart Health (insurance typically covers these without a problem): 

• Apolipoprotein B (ApoB): THE BEST measurement of your cholesterol burden and more accurate than just LDL. It takes into account all of the particles that contribute to heart disease, including LDL, VLDL, IDL, and Lp(a)
  • Normal < 90 mg/dL 
  • If high risk: <80 mg/dL 
• Lp(a): this is a very inflammatory lipid particle that is genetically inherited. You only need to get this test once in your life.
  • <50 ng/dL = do not carry the genetic risk
  • >50 ng/dL = you DO carry the genetic risk and a 2.5x increased lifetime risk of a heart event
• HsCRP: this is a marker of inflammation in the body.
  • Optimal is <1
  • Elevated hsCRP comes with a 4x increased risk in heart attacks and strokes
• Standard lipid panel:
  • Normal LDL is <100mg/dL or <70mg/dL if high risk. Remember that ApoB is more accurate than LDL.
  • Triglycerides (TG) is a great marker for insulin resistance or a sign of excess calories.
    • Normal <150
    • Optimal <100 (some recommend having your TG as close to your HDL as possible
  • Low HDL is associated with an increased risk of heart disease but a raising your HDL probably doesn’t matter based off of newer studies
  • Total cholesterol is meaningless, never look at it.
• Fasting insulin/fasting glucose/hemoglobin A1c: Insulin resistance is a spectrum of illness defined by high insulin levels. Higher insulin levels (and higher blood sugars) damage the endothelium and cause vascular inflammation
  • Fasting insulin: Normal is <20, Optimal is <10
  • Fasting blood sugar: Normal is <100
  • Hemoglobin A1c: Normal is <5.7%; Prediabetes is 5.7-6.4%; Diabetes is 6.5%+

Nice-to-Have Labs for Heart Health (less likely to be covered by insurance): 

These are the labs that are harder and may not be familiar to your clinician. We find that these tests add increased precision when it comes to defining risk and provide closer monitoring of your heart over time. If you think back to how heart disease starts, a lot of these labs are geared at picking up disease when it is just inflammation within the artery wall and before plaque develops. In our clinic, we are only running these labs in our precision health program.

• ApoE status: Not really blood work but rather a genetic test. ApoE is commonly thought of as the “Alzheimer’s Gene” but really is a cholesterol transport gene that affects both the brain and the heart. Knowing ApoE status helps us better fine tune lifestyle/supplement recommendations.
• SdLDL (small dense LDL): smaller LDL particles are more harmful than larger ones. A high sdLDL is also a very early marker of insulin resistance
• Lp-PLA2: a marker produced by immune cells during the development of soft plaque
• OxPL-ApoB: a marker of inflamed cholesterol particles. This is extremely important lab test in patients who have high Lp(a)
• OxLDL: a marker of oxidized LDL, which occurs during plaque formation.
• Homocysteine: elevated homocysteine levels damage the vascular wall and reduce nitric oxide production
• Fibrinogen: a clotting factor
• IL-6: This is a marker of immune activation within the arterial wall
• Cholesterol Balance: helps determine “why” your cholesterol is elevated — increased production vs increased absorption vs poor clearance from the bloodstream
• Fatty Acid Balance: Direct measurement of your body’s levels of saturated fats, Omega 3s and Omega 6s. This is a great way to assess your dietary efforts and where changes or supplementation need to be made.

Now what about imaging?:

So, you’ve identified your risk factors and you’ve had blood work that reveals some abnormalities. Or maybe you’re 40 years old, fairly healthy, but carry a strong family history of heart attacks and strokes. What you need now is imaging that actually looks at your heart and blood vessels to see if vascular inflammation and plaque are present. 

Interestingly, imaging has not really made it into the mainstream of medical guidelines. Most of the guidance revolves around blood work, risk calculators, and medications. But we now have really good ways to peer inside our bodies using ultrasound and CT scans, and I have come to the conclusion that these are indispensable tools to help patients understand their heart health. For starters, actually seeing disease is a very powerful motivator for change. Secondly, abnormal lab work does not equal disease. By not getting a picture of your arteries, both you and your guiding clinician remain in a diagnostic pickle — do you actually have heart disease or not?

Here are the top 3 imaging tests you can get of your heart:

1. CIMT (Carotid Intimal Media Thickness) Ultrasound
   • This is a non-invasive and no-radiation look at the arteries in your neck. Using ultrasound technology, we can measure the thickness of your subendothelial space, the area that heart disease first starts in the artery wall. Studies show that thickness correlates to arterial inflammation and early disease. It can also identify the presence of both soft and hard plaques. 
   • This test is different than the traditional carotid ultrasound, which is only looking at severe blockages (i.e. >50% blockage) and not artery wall thickness.
   • You can repeat this test yearly to monitor your artery health.
   • Great test for patients in their 30s+ with 1-2 risk factors for heart disease and not currently on medication.
   • Not covered by insurance, costs $185. We do these at our office (as of right now, we are the only place offering this test in WNC)
2. Coronary CT for Calcium (aka Calcium Score)
   • CT scan that identifies the presence of hard plaque in the heart arteries
   • The score ranges from 0 to >1000, higher scores meaning more calcium is present. (To me, any number >1 means that you have plaque, and we should take it seriously)
   • It cannot see soft plaque, so a score of 0 does not mean that your vessels are perfectly clear. However, a score of 0 in someone >65yrs old is very reassuring.
   • If you are on a statin, you should not get this test. Statins convert soft plaque to hard plaque, so it’ll always be positive.
   • Great test if 50+ years old and can be paired with a CIMT ultrasound. I recommend getting it every 5-10 years.
   • Not covered by insurance, costs $100 locally.
3. Coronary CT Angiogram
   • CT scan using dye to see all of the vessels around the heart
   • Great at identifying both hard and soft plaque, will also give you a calcium score
   • Most complete look at your heart health but also the most invasive test, higher radiation exposure, involves dye that can harm the kidney (rare)
   • Some scans incorporate AI technology for more precise measurements (i.e. HeartFlow, Cleerly)
   • Great test if you are very high risk, irregardless of age
   • Very expensive (>$1500 out-of-pocket) but may be billed to insurance

I hope that was a helpful overview of both labs and imaging. I don’t expect any of you to be experts in these tests and should really only be interpreted by your medical team. But I wanted you to know what is out there to help you navigate a better heart health prevention plan. If you are high risk and want to know more about your heart, speak with your clinician about these tests and which ones would be most important for you.  

All the best,

Troy Jackson, MD