Abstract 4050: Circumferential Mid-Ventricular Intramyocardial Injections of Alginate Hydrogel Improve Left Ventricular Function and Prevent Progressive Remodeling in Dogs With Chronic Heart Failure
Background: Progressive LV enlargement and increased chamber sphericity are characteristics of heart failure (HF) and are associated with increased mortality and morbidity. We tested the hypothesis that direct mid-ventricular intramyocardial injections of Alginate hydrogel implants (Algisyl-LVR, Symphony Medical, Inc.) into the free wall of the failing LV reduce LV size, restore LV shape, lower LV wall stress and improve LV function.
Methods: A total of 14 dogs with coronary microembolization-induced HF (LV ejection fraction, EF<30%) were studied. Eight dogs received 7 injections of 0.25– 0.35 ml of Alginate during an open-chest procedure and 6 received saline and served as controls. The Alginate or saline injections were made ~1 to 1.5 cm apart along the circumference of the LV free wall halfway between the apex and base starting at the antero-septal groove and ending at the postero-septal groove. LV end-diastolic (ED) volume (EDV), end-systolic (ES) volume (ESV), EF, ES sphericity index (ESSI), ED wall stress (EDWS), deceleration time of early mitral inflow velocity (DT), severity of functional mitral regurgitation (MR) and slope of the ES pressure-volume (P-V) relationship (ESPVR) quantified from P-V loops recorded from conductance catheters during inferior vena caval occlusion were measured before therapy (Pre) and at 17 weeks after therapy (Post). The treatment effect (Δ) was calculated as the difference between Pre and Post.
Results: Compared to saline control, Alginate implants significantly reduced LV EDV, ESV, EDWS and severity of MR (Table⇓). Alginate implants significantly increased LV EF and slope of the ESPVR indicating improved LV systolic performance (Table⇓). Treatment with Alginate implants also showed a safe and non-arrhythmogenic chronic profile.
Conclusion: LV reconstruction using a circumferential pattern of intramyocardial Alginate hydrogel implants represents a novel approach for the treatment of chronic HF.