RESUMO
PURPOSE: We examined the hemodynamic effects of a new, implantable, direct cardiac assist device in an ovine heart failure model. DESCRIPTION: The device, which encompasses both left and right ventricles, is inserted through the pericardial apex and self-expands to encompass the heart without suturing. The intact pericardium anchors the device in place. The device has 2 concentric chamber layers: an internal chamber layer filled with fluid to conform to the heart and an external chamber layer filled with air that provides external compression and negative pressure to aid relaxation. EVALUATION: The device was implanted in 7 sheep with heart failure induced by microsphere embolization. Cardiac performance was assessed for 6 to 8 hours. The cardiac assist device provided cardiac systolic and diastolic assistance, as shown by pressure tracings of the left ventricle and aorta, pulmonary artery flow, and +dP/dt. Central venous pressure decreased during cardiac assistance. No anatomic damage was noted postmortem. CONCLUSIONS: Systolic and diastolic cardiac assistance can be achieved with this device that compresses and relaxes in synchrony with the native cardiac cycle.
Assuntos
Insuficiência Cardíaca , Coração Auxiliar , Animais , Ovinos , Diástole , Ventrículos do Coração , Hemodinâmica , Insuficiência Cardíaca/cirurgia , Pressão Venosa CentralRESUMO
The CorInnova cardiac compression device (CorInnova, Inc., Houston, TX, USA) is designed to provide direct biventricular support, increase cardiac output, and improve ventricular unloading in patients with heart failure. Placed within the pericardium and surrounding both ventricles, the device has two concentric sets of thin-film polyurethane chambers: (1) inner (epicardial) saline-filled chambers that conform intimately to the epicardial surface, eradicating any gaps in the interface between the device and the heart; and (2) outer air-filled chambers cycled to provide epicardial compression during systole and negative epicardial pressure during diastole, consistent with physiological cardiac contraction and relaxation. A superelastic, collapsible Nitinol frame gives the device structure, enables minimally invasive self-deployment, and enhances diastolic filling. Preclinical testing has been extremely promising, with improvements in cardiac output and other cardiac parameters in animal heart failure models. This potentially transformative technology is moving rapidly toward first-in-human use. The CorInnova device may provide an effective device-based solution for patients with heart failure who currently have few or limited mechanical cardiac support options, including patients with biventricular cardiac failure, those with right heart failure, those who are older, and those who are of smaller size. It can be removed easily and requires minimal maintenance. An important, unique feature of this technology is that it provides mechanical cardiac assistance without blood contact or need for anticoagulation. The CorInnova device may be particularly important for those patients who have contraindications to anticoagulation due to allergy, neurological bleeds, or preexisting hemorrhage. No other mechanical circulatory support device addresses these underserved heart-failure populations.
RESUMO
Patients with a diabetic foot ulcer (DFU) suffer disabilities and are at increased risk for lower extremity amputation. Current standard of care includes debridement, topical antibiotics, and weight off-loading-still resulting in low rates of healing. Previous small-scale research has indicated that repeated remote ischemic conditioning (rRIC) is a novel modality that delivers significantly higher DFU healing rates. This proof-of-concept study was performed to expand the research on the utility of rRIC as an adjunctive treatment in the healing of chronic DFUs. Forty subjects (41 wounds) received rRIC treatment three times weekly in addition to standard of care for 12 weeks. Subjects that did not heal in this time frame but had a significant reduction in wound size were eligible to continue for an 8-week extension period. By the end of the extension period, 31 of the 41 DFU wounds (75.6%) in this study were determined to be healed. This compares favourably to the 25-30% standard of care average healing rate. For additional comparison, another group of patients receiving standard of care alone, by the same investigator, was selected and matched by wound size at baseline and wound location. For this matching cohort, after 20 weeks of treatment, only 15 of the 41 DFU comparison wounds (36.6%) were determined to be healed, in line with other standard of care results. In the rRIC treatment group, the 10 wounds that did not heal, experienced an average reduction in wound area of 54.3%. The results of this proof-of-concept study reinforce earlier evidence that the addition of rRIC to local wound care significantly improves the healing of chronic diabetic foot ulcers.
Assuntos
Diabetes Mellitus , Pé Diabético , Úlcera do Pé , Amputação Cirúrgica , Antibacterianos , Pé Diabético/terapia , Humanos , CicatrizaçãoRESUMO
While the number of patients supported with temporary cardiac assist is growing, the existing devices are limited by a multitude of complications, mostly related to contact with the blood. The CorInnova epicardial compressive heart assist device was tested in six sheep using an acute heart failure model. High esmolol dose, targeting a 50% reduction in CO from healthy baseline, resulted in a failure state with mean CO 1.9 L/min. Heart assist with the device during failure state resulted in an average absolute increase in CO of 1.0 L/min, along with a decline in ventricular work to 67.5% of the total LV SW. Combined with repeated success of minimally invasive device implant, the resulting increases in cardiac hemodynamics achieved while still unloading the heart demonstrate the potential of the CorInnova device for temporary heart assist.
Assuntos
Insuficiência Cardíaca/terapia , Coração Auxiliar , Hemodinâmica , Implantação de Prótese/instrumentação , Função Ventricular Esquerda , Animais , Modelos Animais de Doenças , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Teste de Materiais , Desenho de Prótese , Recuperação de Função Fisiológica , Carneiro DomésticoRESUMO
Although remote ischemic conditioning promises significant benefit to patients with a variety of acute and chronic illnesses, development of automated, clinically applicable devices has been slow. At least 3 small companies have launched efforts to develop useful tools intended for sale in European and North American markets. The market challenges and opportunities linked to the development of a cost-effective, reliable, and clinically effective device for the application of remote ischemic conditioning are presented in this article.