Surgical Therapy for Heart Failure

LVAD therapy as a catalyst to heart failure remission and myocardial recovery

The management of chronic heart failure over the past decade has witnessed tremendous strides in medical optimization and device therapy including the use of left ventricular assist devices (LVAD). What we once thought of as irreversible damage to the myocardium is now demonstrating signs of reverse remodeling and recovery. Myocardial recovery on the structural, molecular, and hemodynamic level is necessary for sufficient recovery to withstand explant and achieve sustained recovery post-LVAD. Guideline-directed medical therapy and unloading have been shown to aid in recovery with the potential to successfully explant the LVAD. This review will summarize medical optimization, assessment for recovery, explant methodologies and outcomes post-recovery with explant of durable LVAD.

Bridge to removal: a paradigm shift for left ventricular assist device therapy

Ventricular assist devices have become standard therapy for patients with advanced heart failure either as a bridge to transplantation or destination therapy. Despite the functional and biologic evidence of reverse cardiac remodeling, few patients actually proceed to myocardial recovery, and even fewer to the point of having their device explanted. An enhanced understanding of the biology and care of the mechanically supported patient has redirected focus on the possibility of using ventricular assist devices as a bridge to myocardial recovery and removal. Herein, we review the current issues and approaches to transforming myocardial recovery to a practical reality.

A compact mock circulation loop for the in vitro testing of cardiovascular devices

In vitro cardiovascular device performance evaluation in a mock circulation loop (MCL) is a necessary step prior to in vivo testing. A MCL that accurately represents the physiology of the cardiovascular system accelerates the assessment of the device's ability to treat pathological conditions. To serve this purpose, a compact MCL measuring 600 × 600 × 600 mm (L × W × H) was constructed in conjunction with a computer mathematical simulation. This approach allowed the effective selection of physical loop characteristics, such as pneumatic drive parameters, to create pressure and flow, and pipe dimensions to replicate the resistance, compliance, and fluid inertia of the native cardiovascular system. The resulting five-element MCL reproduced the physiological hemodynamics of a healthy and failing heart by altering ventricle contractility, vascular resistance/compliance, heart rate, and vascular volume. The effects of interpatient anatomical variability, such as septal defects and valvular disease, were also assessed. Cardiovascular hemodynamic pressures (arterial, venous, atrial, ventricular), flows (systemic, bronchial, pulmonary), and volumes (ventricular, stroke) were analyzed in real time. The objective of this study is to describe the developmental stages of the compact MCL and demonstrate its value as a research tool for the accelerated development of cardiovascular devices.

Extra-aortic implantable counterpulsation pump in chronic heart failure

Extra-aortic counterpulsation for the management of chronic heart failure is a novel approach. We report the use of an extra-aortic implantable counterpulsation pump in the management of a 73-year-old patient with severe heart failure refractory to medical therapy. The implantable counterpulsation pump prolonged his life and greatly improved its quality. The patient lived almost 7 months after the implantation of the device and died of septic complications secondary to gas line infection.