Feasibility of Continuous Noninvasive Pulmonary Artery Pressure Monitoring via the Cordella Implantable Pulmonary Artery Sensor

Abstract

Although cardiopulmonary exercise testing (CPET) is considered the gold standard assessment of functional capacity and prognosis in heart failure (HF) patients, pulmonary hemodynamics can be measured during incremental exercise at invasive right heart catheterization or noninvasively at exercise echocar-diography to assess the physiologic responses to exercise and help guide patient management. 1,2 The Cordella PA sensor (Endotronix Inc) transmits pulmonary artery pressures (PAPs) from HF patients to their clinical team, and a harness was developed to allow for hands-free continuous PAP readings. The results of a feasibility study of HF patients who underwent Cordella PA sensor implant and subsequent 6-minute walk test (6MWT) with continuous PAP readings are reported here. The SIRONA 2 clinical trial has been previously described. 3 The study was undertaken in accordance with the Declaration of Helsinki and approved by the relevant competent authorities and independent ethics committees. All patients provided written informed consent. At a follow-up visit, each participant underwent the Cordella 6MWT protocol. To begin, patients assumed a seated position. The reader was then activated to begin recording continuous PAP, a timer was started, and the patients rested for 5 minutes. Then, blood pressure (BP), oxygen saturation (SpO 2), and the Borg Rating and Perceived Exertion (RPE) scale were assessed. Patients then stood for 1 minute before performing the 6MWT. Following the 6MWT, patients were asked to sit, and BP, SpO 2 , and Borg RPE were assessed. Following at least 5 minutes of sitting, BP, SpO 2 , and Borg RPE were assessed again, and the timer and reader were stopped. Continuous PAP waveform processing was performed in LabVIEW Runtime version 2019 (National Instruments) (Figure 1A). Heart rate was derived from the PAP waveform. The 10-second periods before each minute in the test were averaged for both PAP and heart rate for the purposes of plotting and comparing timepoints within the test (Figure 1B). Data are reported as median with IQR. Changes in parameters were compared using repeated-measures Student's t-tests with a significance threshold of P < 0.05. Twelve subjects underwent the Cordella 6MWT with successful continuous PAP measurement. At baseline, the median age was 71.0 years (Q1-Q3: 68.5-74.8 years), 7 (58.3%) were male, and they had a median 6MWT of 370.0 m (Q1-Q3: 321.5-403.5 m). All had NYHA functional class III at baseline but had progressed to NYHA functional class II at the time of the 6MWT. Patients underwent the 6MWT protocol a median of 552 days (Q1-Q3: 379-1,054 days) from implant. The median distance walked was 336.0 m (Q1-Q3: 292.3-389.8 m). Measurement of all hemody-namic variables was feasible in all subjects during the entire study protocol, and PAP was continuously recorded for a minimum of 17 minutes in all cases. PA pressures and heart rate increased significantly during the 6MWT (systolic: þ29.2 mm Hg [Q1-Q3: 23.1-34.7 mm Hg]; diastolic: þ13.2 mm Hg [Q1-Q3: 9.9-16.4 mm Hg]; mean: þ21.1 mm Hg [Q1-Q3: 9.9-16.4 mm Hg]; heart rate: þ24.0 beats/min [Q1-Q3: 18.0-36.0 beats/min]; all values of P < 0.05) and What is the clinical question being addressed? Whether continuous, noninvasive PAP measurement during ambulatory exercise is feasible using an implantable PA sensor. What is the main finding? Continuous, noninvasive PAP measurement using the Cordella PA Sensor system is feasible in HF patients during exercise.