First in Human Experience of a Novel No-implant Interatrial Shunt Device for Heart Failure with Preserved Ejection Fraction

Abstract

<h3>Introduction</h3> Chronic heart failure withpreserved ejection fraction (HFpEF) comprises approximately 50% of all heartfailure diagnoses and currently has limited proven drug or device therapies. Symptomsof HFpEF, particularly dyspnea, are primarily mediated by elevated left atrialpressure. Creation of an interatrial shunt to permit left-to-right atrial flowmay improve dyspnea and other patient outcomes by mediating left atrialdecompression, thereby reducing diastolic filling pressures and improvingexercise tolerance and quality of life. Recently, implantable interatrial shuntdevices have demonstrated promise as a therapeutic option for HFpEF. Deliveringthe physiologic benefit of an interatrial shunt without a permanent cardiacimplant may have clinical advantages. We report the 6-month outcomes ofpatients treated with an implant-free interatrial shunt device. The purpose ofthis first in human study was to evaluate the safety, feasibility anddurability of the percutaneous atrial septectomy enabled by the AlleviantMedical device. <h3>Methods</h3> Key inclusion criteria were NYHAclass II (with history of greater than class II), III and ambulatory class IV,echocardiographic evidence of diastolic dysfunction, elevated peak PCWP andnormal right atrial pressure during supine ergometry. The procedure utilizedfemoral vein access and standard transseptal catheterization techniques. Thedevice was utilized to capture, excise, and remove a precisely sized section ofthe atrial septum to create a therapeutic shunt under fluoroscopic andechocardiographic guidance. <h3>Results</h3> 10 patients were enrolled inthe study. Mean age was 67 ± 8 years. Mean LVEF was 61.1 ± 10.1%. 4 patientswere NYHA class II; 6 were NYHA class III at baseline. The procedure wassuccessful with shunt creation confirmed in all patients (mean shunt size 6.8 ±1.0 mm) and no device or procedure-related adverse events. At 30 days, meanpeak exercise PCWP was reduced significantly (8 ± 10 mmHg, p=.026). At 6 months,NYHA status improved by one class in 7 patients, worsened by one class in 1 patientand did not change in 2 patients. All shunts were open at 6 months with left-to-rightflow and stable size confirmed via TEE (mean shunt size 6.8 ± 0.7 mm across ninepatients). At 6 months, mean 6MWT increased (146 ± 76 m, p<.001), ProBNPdecreased (687 ± 234 pg/ml, p<.001), and KCCQ score increased (24 ± 15,p<.001). No device or procedure-related serious adverse events occurredthrough 6 months. <h3>Conclusions</h3> This initial experiencedemonstrates that percutaneous creation of an implant-free interatrial shunt inpatients with HFpEF is safe and feasible with sustained clinical and hemodynamicimprovement and shunt patency through 6 months. Subsequent clinical studies tocontinue clinical evidence development are currently underway.