Abhi Chavan

Estimation of patient compliance in application of adherent mobile cardiac telemetry device

In an in home usage outpatient setting, patient compliance is a key factor in determining the adoption and efficacy of treatment for any illness and is paramount for patient dependent medical technologies such as mobile patient monitoring systems. As a leader in the development of these technologies, Corventis has deployed its NUVANT™ Mobile Cardiac Telemetry System to thousands of patients around the world. The NUVANT system includes an externally worn adherent sensing device, the PiiX, whose proper application is critical to the on-patient longevity and thus performance of the NUVANT system. Patient compliance in this context is a universal challenge for such patient-applied adherent devices. Understanding and tracking a problem is key to solving it and the integrated suite of vital sign sensors in the Corventis PiiX offers a unique opportunity for extracting patient application compliance information from the incoming health data. Analysis of data from 5000 randomly selected patients has shown that improper application of the PiiX is a factor in 2.3% of patients. However, no reduction in adherent device longevity or performance was observed. Such information is a valuable feedback metric for product design, instructions for use, packaging of medical technologies, level of customer support and replacement costs.

Study of arrhythmia prevalence in NUVANT Mobile Cardiac Telemetry system patients

The Corventis NUVANT™ Mobile Cardiac Telemetry system is an innovative solution in the field of continuous monitoring of symptomatic and asymptomatic cardiac abnormalities to help physicians diagnose and treat non-lethal cardiac arrhythmias. As an FDA cleared product on the market for more than 2 years, the collected body of patient data represents a unique and powerful source of clinical information. Analysis of a sample of 951 NUVANT patients has revealed interesting statistics on the prevalence of various cardiac arrhythmias in the patient population. The population is non-randomized and largely consists of US patients where a traditional Holter Monitor study was negative. The analysis here is focused on classifying the detected arrhythmias using potential therapy solutions as a classifier. Across the total population, 2.2% of patients presented arrhythmias indicating assessment for clinically significant tachycardia, 19% indications of potential bradycardia, 20% had indications of atrial fibrillation, 1% indicating arrhythmias requiring other conditional treatment, and 58% presenting arrhythmias likely not requiring treatment.

A study of activity and body posture with the PiiX mobile body-adherent device.

Remote monitoring of in-home activity and body posture provides useful physiological parameters for understanding patient status and for making clinical judgment in patients living with heart failure. The Corventis PiiX is a mobile chest-adherent device that provides continuously recorded accelerometer data from patients in an in-home setting. In particular, a 3-axis accelerometer enables quantification of full body activity and body posture changes. In this paper, the prevalence of sedentary activity with subject age, the population-wide distribution of upright body posture and resting body posture, and a diagnostic for reduced activity levels and resting body posture is presented with retrospective analysis on a large nonrandomized dataset.

SEEQ ™ MCT wearable sensor performance correlated to skin irritation and temperature

The Medtronic SEEQ™ Mobile Cardiac Telemetry System provides continuous monitoring of symptomatic and asymptomatic cardiac arrhythmias. Deployed across disparate geographies, the device and the patients wearing it are subject to a wide range of weather conditions, specifically differing temperatures. We hypothesized that extremes of temperature would result in degradation of SEEQ system performance due to patient discomfort, perspiration, and other factors. Towards that end, we investigated data from over 5000 devices worldwide, including those linked to patient complaints for discomfort. We found that the data does not show a degradation of wearable performance as defined by artifact or event rate with temperature. However, there was a correlation between patient complaints of discomfort and degraded performance as well as a weak correlation with reduced system longevity at temperatures above 80° F.

Comparison of arrhythmia prevalence in NUVANT Mobile Cardiac Telemetry System patients in the US and India.

The Corventis NUVANT™ Mobile Cardiac Telemetry System provides continuous monitoring of symptomatic and asymptomatic cardiac abnormalities to help physicians diagnose and treat non-lethal cardiac arrhythmias. Analysis of a sample of 2231 US and 1053 Indian NUVANT patients has revealed interesting statistics on the prevalence of various cardiac arrhythmias in the patient populations of the two nations. The population is non-randomized and consists of US patients where often a traditional Holter Monitor study was negative and self-pay Indian patients. Mean age was 61.3 for the US and 57.8 for India with 57% of US patients and 32% of India patients being female. Presentation of specific arrhythmia types was similar across populations with the exception of atrial fibrillation and flutter being more prevalent in the older US population as well as increased prevalence of symptomatic atrial and ventricular ectopic rhythms in all patients and SVT for female patients in India. Utilization as defined by the number of patient triggers was 50% higher for Indian patients.