Abstract 3656: An Intra-ventricular Device as a Potential Mechanical Solution for Diastolic Heart Failure
Introduction: Diastolic heart failure (DHF) accounts for over 40% of HF cases, resulting in significant mortality and morbidity. Treatment is empirical and disappointing. Currently, no device therapy for this mechanical disorder is available. Storage of left ventricular (LV) systolic energy in a spring-device releasing it in diastole may improve diastolic function
Methods: A tripod-like elastic spring device leaning on the LV endocardial surface, from the apex to the papillary muscles level was trans-apically implanted in beating sheep hearts. Safety was assessed in 6 healthy animals followed for up to 6 months after implantation. Efficacy was assessed in 4 animals with LV hypertrophy and diastolic dysfunction, induced by bilateral renal wrapping causing severe hypertension (2 had device implantation, 2 controls had sham procedure). Echocardiography was used to assess hypertrophy and diastolic function. 2D echocardiographic circumferential strain, strain-rate, rotation and reverse rotation were measured.
Results: Safety: all animals recuperated after device implantation without decrease in EF or EDP.
Efficacy: In hypertrophied sheep, LV wall thickened by 20%, and LV mass increased by up to 60%. Peak mid and apical level diastolic strain-rate decreased (1.59 to 1.27 %/sec and 3.52 to 2.06%/sec, respectively). Early relaxation assessed using apical reverse rotation fraction (EARRF) decreased from 34% to 23%. After device implantation (1 month) peak mid and apical diastolic strain-rate and EARRF increased (up to 53%). In controls, deterioration of diastolic markers persisted (EAARF decreased to 16%).
Conclusion: We demonstrated that an intra-ventricular elastic device, transferring systolic energy to diastole, is safe for long term implantation and may improve diastolic function in DHF patients. Consequently, the device is planned to be implanted in human, in the framework of a pilot clinical study.