RESUMO
UNLABELLED: We hypothesized that attachment of elastic coil to the left ventricular (LV) wall, capable of exerting outward forces may allow the transfer of energy from systole to diastole and improve diastolic function. METHODS AND RESULTS: An extra-ventricular-device, composed of a series of elastic elements interposed between spiral screws attached to the epimyocardium of the LV free-wall was developed. The hemodynamic and mechanical effects of the device were tested using a computerized model, an in vitro model utilizing a computerized-controlled fluid pump, eight healthy sheep and 10 mini-pigs induced with diastolic dysfunction by renal wrapping. The computerized and in vitro models predicted a reduction of the LV diastolic pressure curve and partial normalization of the pressure-volume loop. The sheep study demonstrated preservation of animal's wellbeing including maintaining cardiac mechanical function with stable energy transfer from systole to diastole throughout the 6 months follow-up. The mini-pigs study showed an increase in the early diastolic to systolic strain-rate ratio in the mid-endocardial level (23 ± 10%, P = 0.008) and an increase in early apical reverse rotation rate of 50% (P = 0.016 compared to control). CONCLUSIONS: This study presents a novel concept of using a mechanical device to transfer energy from systole to diastole, potentially enhancing diastolic function.