COVID-19 Resource Center

COVID-19 Resource Center

Disclosures: Musialowski reports no relevant financial disclosures.
February 17, 2021
2 min read

Q&A: COVID-19 forces changes to INR testing for patients taking vitamin K antagonists

Disclosures: Musialowski reports no relevant financial disclosures.
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The onset of the COVID-19 pandemic forced health care systems to adapt clinical practice to limit patient exposure and centralize telehealth in routine care all while continuing to provide adequate care.

At Atrium Health Sanger Heart and Vascular Institute in Charlotte, North Carolina, physicians enacted great transformation to address the needs of thousands of high-risk patients receiving vitamin K antagonist therapy, which requires patients to appear frequently at health care facilities for INR testing. Vitamin K antagonist therapy, most commonly warfarin in the United States, is prescribed for stroke prevention in patients with atrial fibrillation and for venous thromboembolism prevention in patients at high risk for it.

Rick Musialowski, MD, director of cardiovascular education at Sanger Heart and Vascular Institute.

In a commentary published in NEJM Catalyst, clinicians at Sanger detailed these changes, which included actively converting patients to a direct oral anticoagulant, which does not require INR testing, based on appropriate indications; extending INR testing intervals; and establishment of mobile INR testing that reduced in-person contact for patients who require continuous management.

Healio spoke with Rick Musialowski, MD, director of cardiovascular education at Sanger Heart and Vascular Institute, about the challenges faced during the transition and the future of telemedicine.

Healio: What significant changes were made at Sanger to minimize risk to patients receiving vitamin K antagonist therapy?

Musialowski: Our team made sweeping and rapid changes to 2,312 patients on vitamin K antagonists. In 5 weeks, we converted 437 patients to an alternative drug that no longer required face-to-face point-of-care testing evaluation and limited COVID-19 exposure. At the same time, the remaining patients had the interval of point-of-care testing reevaluated and extended safely. Lastly, 975 of the remaining patients requiring point-of-care INR monitoring were offered home monitoring. We reduced in-person point-of-care testing by 63% over a 1-year period. During the peak of the pandemic, drive-up and outdoor point-of-care testing was also performed.

Healio: Were there any hurdles to overcome during this transition?

Musialowski: Home INR testing is administered by an independent vendor and requires insurance pre-certification. There was a registration and application process, which delayed implementation. To optimize this process, we worked with a single vendor and the formal prescription was submitted by a single provider. Not all insurance companies provide adequate coverage. The cost is prohibitive in a large portion of the 367 patients still coming into the office for point-of-care testing.

Healio: Were there any noticeable changes in medication adherence during this transition?

Musialowski: During the first 8 months, there was a significant number, 26%, that could not afford the newer and safer medicine. These patients had to resume vitamin K antagonists, and home INR testing was offered. Compliance with vitamin K antagonists was unchanged from baseline care.

Healio: Do you foresee the return of in-person visits?

Musialowski: Telemedicine will become a main component of health care delivery. There will always be a role for face-to-face visits. Certain disease states and important discussions are always better in person. The physician-patient relationship is currently in evolution.

Healio: What is the take-home message for clinicians who see high-risk patients such as those in this cohort?

Musialowski: We recommend that health systems begin by assessing the clinical infrastructure and workflows associated with current care of patients. Issues such as cost (including those directly incurred by the patients), convenience, preference and access will limit that which is achievable with any large change effort. Effecting rapid transformation in care delivery while ensuring patient safety is possible but requires detailed planning and support of all aspects of care delivery.

Healio: Anything else you would like to add?

Musialowski: A partnership with the pharmaceutical industry was formed to facilitate the conversion utilizing free samples during the peak of the pandemic. The outcomes of the study are currently being evaluated. This includes major adverse CV events, medication compliance, bleeding complications and COVID-19 status. The results should be completed within the next few months.

For more information:

Rick Musialowski, MD, can be reached at Sanger Heart and Vascular Institute - Pineville, 10650 Park Road, Suite 220, Charlotte, NC 28210.