Tina-quant® Lipoprotein (a) Gen. 2

For accurate and reliable assessment of cardiovascular risk

  • Elevated levels of lipoprotein (a) (Lp(a)) indicate an increased risk of heart attack and stroke
  • The Tina-quant® Lipoprotein (a) Gen.2 assay is the first automated assay in the market on a consolidated platform to officially follow the European Atherosclerosis Society (EAS) recommendation for nmol/L standardization to ensure an apo (a) independent determination of lipoprotein (a)

This is important because:

  • It is the molarity of Lp(a) particles (rather than their combined mass) that is correlated with risk of cardiovascular disease (CVD)
  • Mass assays (mg/dL) fail to take into consideration the size heterogeneity of Lp(a) particles between individuals. This can result in patient misclassification.

Standardizing against an apo (a) size independent method

  • The Tina-quant® Lipoprotein (a) Gen.2 assay determines the concentration (nmol/L) of Lp(a) , rather than the mass (mg/dL) of Lp(a)
  • This measurement provides a clear estimate of the number of Lp(a) particles independent of the molecular weight of the particle, which can vary from 187,000 to over 662,000 Daltons
  • Levels of Lp(a) can vary up to 1,000-fold among individuals and ethnic groups as the level is predominantly determined by the apo (a) gene
  • To obtain the right values and provide apo (a) size independent results, EAS (European Artherosclerorosis Society) recommends measuring the concentration of particles (nmol/L) rather than total weight (mg/dL)

Measuring Lp(a) levels in terms of concentration rather than mass provides results that are independent of the size of individual particles

size-of-individual-particles

The risk of CVD correlates with the molarity of Lp(a) particles and not the combined mass of Lp(a) particles. Classifying patients based on the results from mass assays may lead to an incorrect assessment of CVD risk. For example, individuals with low numbers of large Lp(a) particles can display similar Lp(a) levels to individuals with high numbers of small Lp(a) particles when analyzed using mass assays, but have a lower risk of CVD.

Size-related bias in immunoassays sensitive to the size heterogeneity of Lp(a) particles

size-of-individual-particles-2

Lp(a) concentrations will tend to be overestimated in samples containing particles larger than the assay calibrator and will tend to be underestimated in samples containing particles smaller than the assay calibrator.

Assay Time 10 min
Sample material Serum, Plasma
Measuring range 7 - 240 nmol/L
Onboard stability 6 weeks
Traceability IFCC reference material SRM2B for nmol/L

Easy, accurate and cost-effective assessment of cardiovascular risk

Clinical benefit

  • Lp(a) values reported in nmol/L are not influenced by isoform size and thus provide a more specific assessment of CVD risk

Benefit for the Lab

  • Tina-quant® Lipoprotein (a) Gen.2 shows excellent correlation to the reference method ELISA
  • Cost-effective, fast, robust, easy to perform, stable over time with excellent accuracy and precision

The inaccuracy of Lp(a) values determined by methods sensitive to apo (a) size significantly affects the assessment of individual risk status for coronary artery disease:
Marcovina, S.M., Albers, J.J., Scanu, A.M., Kennedy, H., Giaculli, F., Berg, K., Couderc, R., Dati, F., Rifai, N., Sakurabayashi, I., Tate, J.R., Steinmetz, A. (2000). Use of a reference material proposed by the International Federation of Clinical Chemistry and Laboratory Medicine to evaluate analytical methods for the determination of plasma lipoprotein(a). Clin Chem. Dec;46(12), 1956-67.

Utilization of an inadequate method for Lp(a) is highly likely to lead to increased numbers of both false negatives and false positives. This will lead to the potential misclassification of a significant number of both high and low risk patients:
Marcovina, S.M., Koschinsky, M.L., Albers, J.J., Skarlatos, S. (2003). Report of the National Heart, Lung, and Blood Institute Workshop on Lipoprotein (a) and Cardiovascular Disease: Recent Advances and Future Directions. Clin Chem 49, p.1785-1796

Lp(a) particles may provide a more specific assessment of CVD:
McConnell, et al. Abstract 3608: Lipoprotein (a) Cholesterol, But Not Lp(a) Mass, Is An Independent Predictor Of Angiographic Coronary Artery Disease And Subsequent Cardiovascular Events In Patients Referred For Coronary Angiography. Circulation. 2007.116.II.818

European Atherosclerosis (EAS) consensus panel suggest to screen patients at intermediate or high risk of CVD/CHD on Lp(a):
Nordestgaard, B.G., Chapman, M.J., Ray, K., Borén, J., Andreotti, F., Watts, G.F., Ginsberg, H., Amarenco, P., Catapano, A., Descamps, O.S., Fisher, E., Kovanen, P.T., Kuivenhoven, J.A., Lesnik, P., Masana, L., Reiner, Z., Taskinen, M.R., Tokgözoglu, L., Tybjærg-Hansen, A. (2010). European Atherosclerosis Society Consensus Panel. Lipoprotein(a) as a cardiovascular risk factor: current status. Eur Heart J 31(23), 2844-53.