Frequently Asked Questions

Q: What is the difference between the VAP Cholesterol Test and the routine lipid panel?

A: The VAP Test provides all the information found in a routine lipid panel, plus measurements of all known cholesterol subclasses that play important roles in the development of CAD. The additional information provided by the VAP Test improves the ability to predict heart disease risk to more than 90%. It also directly measures LDL cholesterol. In contrast, the routine cholesterol test detects only about 40% of people at risk. The VAP Test also measures LDL density—important because patients with small, dense LDL have a four-fold increased risk of developing heart disease.

Q: Why is a direct measurement of LDL important?

A: The NCEP ATP III recommends that LDL be directly measured as a new feature of the guidelines. LDL is not directly measured in today’s routine lipid panels. Rather, it is calculated using the Friedewald equation: [LDL] = [total cholesterol] – [HDL] – [triglycerides/5]. Thus, calculated LDL is falsely low in patients with elevated triglycerides, and it does not correlate well in patients with diabetes, coronary disease, or other atherosclerotic diseases.

Q: How can the VAP Test help customize patient treatment?

A: The availability of more sophisticated cholesterol treatments points to broader use of the VAP Test because results will help physicians more specifically match a drug or combination of drugs with a patient’s cholesterol profile. The VAP Test’s breakdown of lipid subfractions is vital in determining appropriate treatments. For example, elevated Lp(a) doubles the risk for CAD and requires niacin, fenofibrate, estrogen, or N-3 PUFAs (fish oils). IDL is 10 times more atherogenic than LDL on a mg for mg basis and requires a statin plus niacin in combination. For more information, click here to request a free copy of “Using VAP Expanded Lipid Testing to Develop Optimal Patient Treatment Plans” by lipid expert Paul Ziajka, M.D., Ph.D.

Q: What is meant by “emerging risk factors” for heart disease?

A: The NCEP ATP III guidelines discuss a number of emerging risk factors for heart disease, including small, dense LDL and lipoprotein (a), or Lp(a). LDL is not present in the circulation as one well-defined structure; but rather it is present as a continuum of size and density. The presence of small, dense LDL quadruples the risk of heart disease compared with the same total LDL concentration present in a large, buoyant form. Lp(a) is a genetic risk factor that has been shown to be 10 times more atherogenic than LDL on a mg per deciliter basis. Thus, it is important to measure Lp(a) in patients with a family history of premature atherosclerosis. Importantly, these emerging risk factors are not measured by the routine lipid panel.

Q: Can the VAP Test detect the metabolic syndrome?

A: The “atherogenic lipid triad” of low HDL, high triglycerides, and small, dense LDL—also known as the metabolic syndrome—is described in NCEP ATP III guidelines as a widespread and underdiagnosed health problem. It is crucial to understand that atherosclerosis begins developing in these patients, and they maysuffer coronary events, before their blood sugar starts to rise. The expanded lipid panel may be superior to fasting insulin levels and glucose tolerance tests for detecting the metabolic syndrome, as well as providing a better guide to therapy.

Q: Do the NCEP guidelines point to the use of an expanded lipid panel like the VAP Test?

A: The NCEP ATP III guidelines offer new opportunities to improve the early detection and treatment of heart disease. ATP III focuses attention on the metabolic syndrome, as well as several emerging risk factors and secondary targets of therapy that are not measured with the routine lipid panel. The VAP Test allows clinicians to comply with ATP III at a cost comparable to the routine lipid panel.

Q: Are VAP Test results accurate?

A: Yes. The VAP Test is based on ultracentrifugation, the gold standard for reference lab lipid measurement. The test is processed at Atherotech’s CLIA-approved diagnostic laboratory. In addition, Atherotech has the accuracy of the VAP Test confirmed by two highly recognized lipid standardization programs—the Core Laboratory for Clinical Studies at Washington University, St. Louis, MO. and Proficiency Testing Program by NY State Department of Health.

Q: Is the VAP Test cost-effective?

A: The VAP Test costs about the same as the routine cholesterol test and is reimbursed by most insurance carriers. It is more cost-effective than running the several tests needed by other labs to report what a single VAP test will report. Atherotech also accepts assignment from Medicare and Blue Cross/Blue Shield PPO.

Q: Is the VAP test be covered by insurance?

A: The VAP test is reimbursed by Medicare, Medicaid and many other health insurance plans. Please contact Atherotech Client Services at 877.901.8510 or use this form to send an inquiry.

Q: How can I incorporate the VAP Test into my practice?

A: From sample collection and shipping to billing and customer support, integrating the VAP Test into your practice is easy. All necessary items, including express shipment packaging and prepaid airbills, are supplied. A standard 5 ml venous blood draw is the required sample, which is then forwarded to Atherotech’s state-of-the-art reference laboratory for processing. The comprehensive results are generally provided within 72 hours via fax or secure website.

Q: How accurate is the apo-B data in determining risk compared with the gold standard?

A: Atherotech has developed a novel procedure to calculate apoB utilizing non-HDL-cholesterol along with lipoprotein density distribution using the patented VAP ultracentrifugation method. Atherotech has thoroughly validated this new procedure by comparing its calculated apoB with the gold standard* using serum from 1,797 patients. This comparison has yielded an excellent correlation coefficient (r = 0.96) with bias of only 3.8%. The long term (40 days) reproducibility of VAP apoB is 3.0% CV (coefficient of variance). The VAP apoB calculation work was accepted through a peer review process for presentation at 2007 Annual Meeting of American Association of Clinical Chemistry (AACC), and was subsequently published by AACC as an abstract.

     * apoB immunoassay provided by Abbott Diagnostics; calibrated against
        WHO/IFCC/CDC Apolipoprotein Reference Material

Q: What percent of patients would have been mismanaged if treatment was based solely on standard testing?

A: To answer this with actual test results Atherotech pulled test data from the 2nd half of 2007 for which Atherotech performed both Standard Lipid Panel (SLP) testing and the VAP test. There were 4,862 such specimens. These were not subject to any sampling or filtering criteria. Our findings:

• 904 (19%) patients had a calculated LDL using the Friedewald equation that was more than 10% lower than the directly measured LDL from the VAP. These underestimated LDL values from SLP represent patient risk that would have gone unnoticed without VAP testing.
• 2,866 (59%) patients had emerging risk factors present that could lead to reducing target LDL by an additional 30 mg/dl, based on ATP III recommendations. This would likely lead to more aggressive treatment to mitigate these added risk factors. None of these risk factors could be obtained using SLP.
• 493 (10%) patients had atherogenic dyslipoproteinemia, characterized by the combined presence of small dense LDL, low HDL, and elevated triglycerides. ATP III recommends nicotinic acid for this risk combination, rather than statin treatment. This diagnosis and treatment strategy would be missed using SLP alone, since it does not provide information about LDL density.

In total, 3,100 (64%) patients had one or more of these findings that would lead to more accurate risk identification and/or different therapeutic treatment than would occur using “standard testing” (SLP).