Abstract Body: Background: The prevalence of pseudo- or missed- hypertension (HTN) due to inaccurate blood pressure (BP) devices during Cardiac Rehabilitation (CR) is unknown. The first step in the workflow of a home-based BP management program is to validate home BP devices for those who already own a device. The goal of this study is to quantitate the proportion of already-owned inaccurate devices on patients starting CR. Devices that do not validate at the time of this screening would need to be replaced before engaging in medication management; this would prevent BP undertreatment and/or overmedicating patients while also engaging in lifestyle modifications in CR.

Methods: Based on the American Medical Association self-measured BP device calibration test, we retrospectively reviewed 188 consecutive devices for validations in 160 CR patients enrolled in a single center. Validations consist of i) confirming use of an arm cuff device, ii) use of appropriately sized cuff, and iii) accuracy of home device readings. Once the arm with the highest BP is determined, the patients rest for 5 minutes quietly, and the arm is properly positioned before obtaining a total of 5 BP readings using the home device (readings #1, #2 and #4) and the office device as ground truth (readings #3 and #5). Devices were classified as validated based on a two-step formula to determine that the difference between the average BPs from both devices is ≤5 mmHg in the first step or ≤10 mmHg in the second step.

Results: Thirty-two of the 188 (17%) tested devices failed to validate. Of these, 1 (3%) had the wrong cuff size, 4 (13%) were wrist devices, and 2 (6%) gave erratic measurements. Thirty-one of 160 (19%) patients had their validations failed. Twenty-four of them had their devices not valid based on differences between device measurements; 18 (75%) had elevated BP that would have been over or under- estimated by their home devices.

Conclusion: High BP at home is a treatable risk factor that is often missed when performing initial assessments of high-risk CR patients. Our data, 19% of patients with inaccurate home devices, supports that the first step in a home-based BP management program ought to confirm that already-owned devices are accurate before they are used. Furthermore, we propose that home BP devices are routinely validated upon CR enrollment to minimize inappropriate medication management of pseudo- or missed- HTN among these high risk patients.