AIMS:Impaired left ventricular diastolic function leading to elevated left atrial pressures, particularly during exertion, is a key driver of symptoms and outcomes in heart failure with preserved ejection fraction (HFpEF). Insertion of an interatrial shunt device (IASD) to reduce left atrial pressure in HFpEF has been shown to be associated with short-term haemodynamic and symptomatic benefit. We aimed to investigate the potential effects of IASD placement on HFpEF survival and heart failure hospitalization (HFH).METHODS AND RESULTS:Heart failure with preserved ejection fraction patients participating in the Reduce Elevated Left Atrial Pressure in Patients with Heart Failure study (Corvia Medical) of an IASD were followed for a median duration of 739 days. The theoretical impact of IASD implantation on HFpEF mortality was investigated by comparing the observed survival of the study cohort with the survival predicted from baseline data using the Meta-analysis Global Group in Chronic Heart Failure heart failure risk survival score. Baseline and post-IASD implant parameters associated with HFH were also investigated. Based upon the individual baseline demographic and cardiovascular profile of the study cohort, the Meta-analysis Global Group in Chronic Heart Failure score-predicted mortality was 10.2/100 pt years. The observed mortality rate of the IASD-treated cohort was 3.4/100 pt years, representing a 33% lower rate (P = 0.02). By Kaplan-Meier analysis, the observed survival in IASD patients was greater than predicted (P = 0.014). Baseline parameters were not predictive of future HFH events; however, poorer exercise tolerance and a higher workload-corrected exercise pulmonary capillary wedge pressure at the 6 months post-IASD study were associated with HFH.CONCLUSIONS:The current study suggests IASD implantation may be associated with a reduction in mortality in HFpEF. Large-scale ongoing randomized studies are required to confirm the potential benefit of this therapy.

Objective: Evaluation of baseline and 6-month transthoracic echocardiographic (TTE) parameters in patients with Heart Failure with a Preserved Ejection Fraction (HFpEF) treated with a novel device that creates a controlled left to right interatrial shunt (IASD). Methods: Patients with HFpEF, as defined by LV ejection fraction (EF) ≥ 40%, New York Heart Association (NYHA) class II–IV, elevated pulmonary capillary wedge pressure (PAWP, ≥ 15 mmHg at rest, or ≥ 25 during bike exercise), central venous pressure (CVP) <15 at rest mmHg were enrolled in the study and underwent IASD implantation. Complete per protocol study TTE were performed at the implant sites and analyzed at an independent echo core laboratory. Results: Of 102 patients enrolled, 66 qualified with mean age 69 ± 8.3 years and 65% female. Baseline hemodynamics includes resting and exercise CVP of 9.0 ± 3.7 and 17.5 ± 6.2 mmHg respectively. Resting and exercise PAWP were 17.4 ± 5.3 and 34.0 ± 8.6 mmHg respectively. 57 underwent IASD implantation. Independent core lab analysis of resting TTE at enrollment and at 6-month follow up (6 MFU) demonstrated no evidence of IASD device thrombus, migration, or excessive mobility. Left to right color Doppler flow was present in all implanted patients. At 6 MFU, an increase in estimated mean RA volume indexed to BSA (4.6 cm^3/m2, p = 0.018) was noted. Increased estimated mean RV diastolic volume indexed to BSA was also observed (5.06 cm^3/m2, p <.001). Reduction in estimated LV mean diastolic volume indexed to BSA (6.15 cm^3/m2, p =0.02) was noted. There was no significant change in diastolic LA volume indexed to BSA (0.16cm^3/m2, p =0.939). There was no significant change in RV systolic function as assessed by TAPSE at 6 MFU (p = 0.973). Conclusion: At 6 MFU post, safe implant of the IASD in HFpEF patients was achieved with Doppler left to right shunt flow present and no device malfunction or thrombus. Small increases in estimated mean RA and RV diastolic volume indexed to BSA were observed with the creation of a left to right shunt. Similar reduction in mean LV diastolic volume indexed to BSA was noted. There was no significant change in LA volume indexed to BSA. There was no significant change in RV systolic function as assessed by TAPSE. These findings indicate that a left to right interatrial shunt can be safely created with the iASD with a small impact on left and right ventricular estimated volumes and no impact on RV function as assessed by TAPSE.