Novel Noninvasive Direct Lung Water Measurement Using KYMA mCor Technology in CHF: A Validation Comparison Study Using Invasive Hemodynamic and "Gold Standard" Extravascular LUNG Water Determination

Michael Jonas ¹ Tal Mandelbaum ³ Galia Karp ² Nimrod Adi ²

¹Heart Institue, Kaplan Medical Center, Rehovot
²Intensive Care Unit, Kaplan Medical Center, Rehovot
³Department of Anesthesia and Critical Care, chaim Sheba Medical Center, Ramat Gan

Introduction- Decompensation of heart failure may manifest as pulmonary congestion or edema – an acute increase in extravascular lung fluid with dire clinical consequences. No direct, reliable, simple and non-invasive method is available for accurate assessment of thoracic fluids. Such a device for measuring lung water content may improve in-hospital management, and potentially reduce Re-hospitalizations For ambulatory CHF patients. KYMA developed a miniature external patch device, monitoring Lung water content by analyzing electromagnetic ("radar") signals, propagated through tissue layers, where Conduction is highly related to the amount of accumulated fluids.

We compared and correlated KYMA's non-invasively measured Lung water index (KLWI) with the invasive hemodynamic and thermodilution based assessment of extravascular lung water level in a unique sheep model of acute pulmonary edema.

Methods-Acute pulmonary edema was induced in 7 sheep by volume and pressure overload using stepwise increased intravenous noreadrenaline (NA) and dextrane. KYMA measurements of LWI were compared to PICCO thermodilution based extravascular lung volume water (EVLW) as the reference gold standard. Multiple hemodynamic invasive parameters including LVEDP and swan ganz catheter were collected.

Results- All 7 sheep, developed gradual increase in LVEDP with onset of pulmonary congestion until fulminant pulmonary edema. A consistent linear correlation between measurements of invasive EVLW and non-invasive Kyma patch KLWI was found (Figure). KYMA's system was able to detect dynamic accumulation of lung water in a range of 40-50cc increments while the change in fluid content between normal and congested lung ranges between 250cc and 500cc

Conclusions–KYMA's external, miniature patch device yielded a lung water fluid index with excellent correlation to invasive lung water and hemodynamic measurement. The demonstrated accuracy and sensitivity of the Kyma technology as reflected in the current study supports its use for high resolution precise thoracic fluid monitoring. Human clinical trials with the Kyma patch are on-going