# Noninvasive Hemodynamic Assessment by a Sensor Patch: The PATCHWRK (PortAble TeCHnology for Wireless caRdiomyopathy tracKing) Study

## TL;DR

A wearable sensor patch called SANSA can accurately measure heart function timing intervals, potentially enabling early detection of heart disease without needing traditional echocardiography.

## Contribution

The study introduces a noninvasive sensor patch that estimates key cardiac timing intervals with accuracy comparable to echocardiography.

## Key findings

- The SANSA patch accurately estimated diastolic filling time (ICC 0.92), pre-ejection period (ICC 0.74), and ejection time (ICC 0.76) compared to echocardiography.
- The patch's measurements showed variability within the same range as different echocardiographic views.
- Longitudinal monitoring using the patch could help detect early signs of cardiomyopathy.

## Abstract

Echocardiographic timing intervals provide prognostic information in patients with preclinical cardiac dysfunction. Reduced diastolic filling time (DFT) identifies left bundle branch block patients at risk for cardiomyopathy. The need for specialized equipment limits the utility of echocardiography (echo) for longitudinal assessment.

The purpose of this study was to evaluate a multimodal sensor patch’s (SANSA) assessment of DFT, pre-ejection period (PEP), and left ventricular ejection time (LVET).

Fifty patients undergoing echo were prospectively enrolled and had simultaneous SANSA patch recording and echo. Timing intervals were analyzed using continuous wave, pulsed wave, and tissue Doppler imaging. SANSA electrocardiogram, seismocardiogram, and phonocardiogram data were independently analyzed to identify valve openings/closures for DFT, PEP, and LVET estimation. Agreement between echo and SANSA estimates was assessed using intraclass correlation coefficients (ICC) and compared with agreement between echo views.

Forty-six of the 50 patients (92%) had analyzable data. The mean ejection fraction was 53% ± 8%; 13 patients (26%) had left bundle branch block. Echo-estimated mean DFT, PEP, and LVET were 416 ± 139 milliseconds (ms), 108 ± 32 ms, and 300 ± 36 ms, respectively. SANSA-estimated DFT, PEP, and LVET were 431 ± 135 ms, 91 ± 35 ms, and 285 ± 43 ms, respectively. The ICC for SANSA vs echo was 0.92 for DFT, 0.74 for PEP, and 0.76 for LVET. The ICC for tissue Doppler imaging vs pulsed wave estimates within the same patients was 0.93 for DFT, 0.83 for PEP, and 0.69 for LVET.

SANSA patch monitoring accurately measures key cardiac timing intervals to within the variability observed between echo views. As these intervals have prognostic value, SANSA-based longitudinal monitoring may facilitate early cardiomyopathy detection.

•Ambulatory assessment of cardiac timing intervals can provide valuable prognostic information in preclinical cardiac dysfunction.•The multimodal SANSA patch estimates cardiac timing intervals within the error observed between echocardiographic views.•Longitudinal monitoring of these intervals may facilitate early recognition and intervention in high-risk patients.

Ambulatory assessment of cardiac timing intervals can provide valuable prognostic information in preclinical cardiac dysfunction.

The multimodal SANSA patch estimates cardiac timing intervals within the error observed between echocardiographic views.

Longitudinal monitoring of these intervals may facilitate early recognition and intervention in high-risk patients.