Remote Home Prothrombin Time (PT)/International Normalized Ratio (INR) Monitoring and Patient Management System

The creation of optimal devices for patient self-testing protocols for anticoagulation management is an area of active medical research. The current pilot study represents the initial step in the development of a new customized device for this purpose, the vMetrics - Anticoagulation Monitoring System. The v-Metrics Anticoagulation Monitoring System (vMetrics AMS) is defined by: 1. A PT/INR home monitoring unit which interfaces to FDA approved PT/INR home monitors such as the Hemosense INRatio device, and 2. an anticoagulation clinic patient management application which manages patient communications, database of prior test results, testing schedules, and communication to an EMR.

The INR home-monitoring system to be tested in this study will address several of the limitations of currently available technologies and practices for standard and home INR self-testing. The proposed project will develop a self-testing device that maximizes safety and efficiency for both the patient and the health care provider. The monitoring device (vMetrics) allows the wireless transmission of the INR result from an approved home INR measuring monitoring device (ex:HemoSense - INRatio) to a secure database in a health care provider staffed anticoagulation clinic. The device will also collect yes/no responses to a set of standard questions from the subject to assure patient safety and determine optimal Coumadin dosing. Upon receipt of the patient data, the Coumadin provider can review the INR result and responses to the questions and use standard Coumadin dosing protocols and clinical judgment to transmit dosing instructions back to the patient through the device. A calendar schedule of dosing until the next scheduled INR check will be transmitted to the patient. In certain instances (i.e., high INR > 5), the device will transmit instructions to call the Coumadin clinic. The subject will confirm receipt of the Coumadin dose sent to him/her by pressing a button on the device (which transmits the confirmation back to the database). This process may reduce inconvenience to the subject, the INR value is reported directly from the device reducing the possibility of error, two-way communication is wireless and will reduce the need for telephone contact, thus potentially saving health care provider and patient time. In addition, the data from the encounter will be available in a form that can be entered into the patient's electronic medical record. The patient will enter data into the device using a 4-digit passcode that will allow for security of data.

In addition to coordinating INR transmission through the home INR device, a customized database will provide a platform for the anticoagulation clinic patient management application (Wireless Home Coumadin clinic). This platform which will organize the workflow of the Coumadin provider to more easily determine which patients are due (or overdue) for monitoring, and which patients have transmitted an INR value and questionnaire and are awaiting a response.

Inclusion criteria

• Ages 18-80 years
• Requires long-term oral anticoagulation therapy for one of the following indications:

• Venous thromboembolism (deep vein thrombosis or pulmonary embolism)
• Arterial thromboembolic event(s)
• Atrial fibrillation
• Mechanical heart valve
• INR goal set at 2-3 by supervising physician
• Subject has been followed in the Vascular Medicine Coumadin program for at least 3 months
• No INR values > 7, and no major thrombotic or bleeding complications within the preceding 3 months of follow-up in the Coumadin program.
• Subject has been compliant with INR monitoring during period of enrollment in the Vascular Medicine Coumadin program.
• Physically able and willing to perform finger stick INR measurements on self
• Able to use the hand-held monitoring device and have adequate vision to read information on the device screen

Exclusion criteria

• Inability to speak and read English
• Anticipated interruption in anticoagulation within the next 6 months (e.g., for elective major surgery, pregnancy)
• Cognitive impairment which makes ability to perform necessary procedures related to the remote home monitoring device unlikely