K990398 · Array Medical, Inc. · JOZ · Dec 1, 1999 · Hematology
Device Facts
Record ID
K990398
Device Name
PLATELETWORKS
Applicant
Array Medical, Inc.
Product Code
JOZ · Hematology
Decision Date
Dec 1, 1999
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 864.5700
Device Class
Class 2
Indications for Use
Plateletworks is an in vitro diagnostic screening assay for the determination of % platelet aggregation in fresh whole blood samples taken during cardiac interventional procedures; as measured by a change in platelet count due to activation of functional platelets and is designed for use on the Ichor" hematology analyzer.
Device Story
Plateletworks is a unitized screening assay for whole blood platelet aggregation. It utilizes the Ichor hematology analyzer, which employs electronic impedance to count platelets. The process involves measuring a baseline platelet count in a whole blood sample, then measuring the platelet count in a second sample exposed to a platelet agonist (e.g., ADP or collagen). Functional platelets aggregate into clumps upon agonist exposure and are excluded from the count in the second sample. The device calculates percent aggregation using the formula: (Baseline Count - Agonist Count) / Baseline Count * 100. Used at the point-of-care during cardiac interventional procedures, the assay provides results in approximately five minutes. Healthcare providers use the output to identify trends in platelet dysfunction, aiding clinical decision-making during cardiac procedures. It serves as a screening tool; abnormal results necessitate further diagnostic investigation.
Clinical Evidence
Clinical validation involved testing 189 (collagen) and 225 (ADP) samples from healthy volunteers and patients undergoing cardiopulmonary bypass or cardiac catheterization. Comparison against PRP aggregometry showed positive correlations: Pearson r=0.82 (collagen) and 0.83 (ADP). Non-parametric tests (Spearman Rho, Kendall Tau) confirmed significant positive associations (p<0.001).
Technological Characteristics
Unitized screening assay for use with Ichor hematology analyzer. Sensing principle: electronic impedance for platelet counting. Measures change in platelet count post-agonist activation. Reported as percent aggregation. Designed for point-of-care clinical setting.
Indications for Use
Indicated for determination of % platelet aggregation in fresh whole blood during cardiac interventional procedures. Used at point-of-care as a screening tool for trends suggestive of platelet dysfunction in adults (18-85 years). Abnormal results require repeat testing or further investigation with definitive methods.
Regulatory Classification
Identification
An automated platelet aggregation system is a device used to determine changes in platelet shape and platelet aggregation following the addition of an aggregating reagent to a platelet-rich plasma.
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# 510(k) Summary of Safety and Effectiveness Information Plateletworks™ Platelet Aggregation Assay
Array Medical, Inc. One Harvard Way, Suite 5 Hillsborough Campus Somerville, NJ 08876 (908)707-8872
Contact: David Carville, Ph.D., (908)707-8872; (219)237-4829
Date: June 25, 1999
Device Names:
Trade Name: Plateletworks
Common Name: Platelet Aggregation Assay
Classification Name: System, Automatic Platelet Aggregation
Legally Marketed Device:
Sigma Platelet Aggregation Reagents, K822733, K832929
Chrono-log Platelet Aggregometer, K77198, K830749, K851025
Device Description:
Plateletworks is a unitized screening assay for determining platelet aggregation in a whole blood sample using the Ichor hematology analyzer. The Plateletworks methodology is an adaptation of platelet aggregometry that is extremely simple, and quick to perform (results are available in about five minutes). This method involves using the Ichor hematology analyzer (based on electronic impedance principles) to measure total platelet count in a whole blood sample and then to redetermine the number of platelets in a second sample that has been exposed to a known platelet agonist. The agonist will stimulate those platelets which are functional to aggregate into clumps, and they will not be counted as platelets in the second sample. The difference in platelet counts between samples one and two provides a direct measurement of platelet aggregation and is reported as percent aggregation as per the following equation:
Baseline Platelet Count - Agonist Platelet Count x 100 = % Aggregation
Baseline Platelet Count
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#### Intended Use:
Plateletworks is an in vitro diagnostic screening assay for the determination of % platelet aggregation in fresh whole blood samples taken during cardiac interventional procedures; as measured by a change in platelet count due to activation of functional platelets and is designed for use on the Ichor" hematology analyzer.
#### Comparison with Predicate Device:
The Plateletworks Platelet Aggregation Assay is substantially equivalent to Sigma platelet aggregation reagents, previously cleared under Document Control # K822733 and K832929, used on the Chrono-log Platelet Aggregometer (Model 560-VS), previously cleared under Document Control # K771198, K830749 and K851025. These products are currently in commercial distribution by Sigma Diagnostics, St. Louis, MO and Chrono-log Corporation, Havertown, PA, respectively.
#### Substantial Equivalence:
Correlation of the Plateletworks assay to platelet aggregometry on platelet rich plasma (PRP) is supported by data generated by testing male and female adults, between the ages of 18 and 85, at three clinical sites. This includes healthy volunteers, patients undergoing cardiopulmonary bypass surgery, and patients undergoing cardiac catheterization.
All blood samples, for performing both Plateletworks assays and PRP aggregometry, were acquired from in-dwelling lines or venipuncture using established methods. For performing both the Plateletworks assays and PRP aggregometry, the manufacturers' recommendations were adhered to as per instructions provided in the package insert for each test system.
Regression analysis (correlation coefficients) was performed to assess the agreement between the two methods (i.e., Plateletworks and PRP aggregometry). Positive correlations were demonstrated for each agonist tested (ADP and collagen). See Figures 1 and 2
Image /page/1/Figure/9 description: This image is a scatter plot comparing PRP Aggregometer % Aggregation on the y-axis and Plateletworks % Aggregation on the x-axis. The plot includes a regression line with the equation y = 0.7743x + 1.3002 and an R-value of 0.83. The data points are clustered, showing a positive correlation between the two aggregation measurement methods, with most points concentrated in the higher percentage ranges.
Image /page/1/Figure/10 description: This image is a scatter plot comparing PRP Aggregometer % Aggregation and Plateletworks % Aggregation. The x-axis represents Plateletworks % Aggregation, while the y-axis represents PRP Aggregometer % Aggregation. The data points are scattered across the plot, showing the relationship between the two variables. A regression line is drawn through the data, and the equation of the line is y = 0.9224x + 2.1945, with an R-squared value of 0.82.
Image /page/1/Figure/11 description: The image shows the text "Figure 1. ADP". The text is in a serif font and is left-aligned. The number 1 is followed by a period.
Figure 2. Collagen
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29
However, it is recognized that correlation coefficients measure the strength of the relationship between the methods and not the agreement between them (Bland JM, Altman DG: Statistical methods for assessing agreement between two methods of clinical measurement. Lancet 1986;Feb:307-310.) Further, since the data for both aggregation systems are bounded by 100% as the upper limit of aggregation, regression analysis is not expected to describe a predictive relationship. Therefore, the data from the clinical sites where substantial equivalence testing was performed were also subjected to the non-parametric analyses of both Kendall Tau and Spearman Rho which "test for a positive correlation without specifying linearity". The results from these analyses are shown (with the regression analysis).
| | N | (Pearson) r | Spearman Rho | Kendall Tau |
|----------|-----|-------------|--------------|-------------|
| Collagen | 189 | 0.82* | 0.80* | 0.58* |
| ADP | 225 | 0.83* | 0.68* | 0.50* |
### Comparative Data: Plateletworks vs. PRP Aggregometry
*P<0.001 two-sided test of positive association significant
These data support the use of the Plateletworks assay to measure platelet aggregation in the clinical setting (near-patient testing).
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Image /page/3/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a stylized caduceus symbol, which is a staff with two snakes coiled around it, overlaid on a human profile. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" is arranged in a circular fashion around the symbol. The logo is black and white.
## DEC - 1 1999
Food and Drug Administration 2098 Gaither Road Rockville MD 20850
David Carville, Ph.D. Vice President, New Product Development Array Medical, Inc. One Harvard Way, Suite 5 Hillsborough Campus Somerville, New Jersey 08876
Re: K990398 Trade Name: Plateletworks™M Regulatory Class: II Product Code: JOZ Dated: September 3, 1999 Received: September 15, 1999
Dear Dr. Carville:
We have reviewed your Section 510(k) notification of intent to market the device referenced above and we have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.
If your device is classified (see above) into either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the Current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic QS inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in regulatory action. In addition, FDA may publish further announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.
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Under the Clinical Laboratory Improvement Amendments of 1988 (CLIA-88), this device may require a CLIA complexity categorization. To determine if it does, you should contact the Centers for Disease Control and Prevention (CDC) at (770)488-7655.
This letter will allow you to begin marketing your device as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.
If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4588. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll free number (800) 638-2041 or at (301) 443-6597 or at its internet address "http://www.fda.gov/cdrh/dsmamain.html"
Sincerely yours,
Steven Autman
Steven I. Gutman, M.D., M.B.A. Director Division of Clinical Laboratory Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
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K990398 510(k) Number (if known):
Plateletworks ™ Device Name:
Indications for Use:
Plateletworks is an in vitro diagnostic screening assay for the determination of % platelet aggregation in fresh whole blood samples taken during cardiac interventional procedures as measured by a change in platelet count due to activation of functional platelets. It may be used at the point-of-care on the Ichor hematology analyzer as a screening tool for the detection of trends suggestive of platelet dysfunction. Any abnormal baseline or otherwise suspicious result would require repeating the Plateletworks test procedure and/or further additional investigation with more definitive test methods, including conventional platelet aggregometry.
(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
(Division Sign-Off)
Division of Clinical Laboratory Devices 11998398
510(k) Number
Rescuption ✓
(Optional Format 3-10-98)
(Posted July 1, 1998)
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