Left ventricular assist devices: bridges to transplantation, recovery, and destination for whom?

Application of mechanical cardiac support now requires consideration of a wider range of goals beyond bridging to transplantation to include destination therapy and perhaps bridging to recovery.1,2 Responsible dissemination of the technology requires identification of patient populations from which to select candidates most likely to benefit. At this early stage, benefit is most apparent against a high background mortality from end-stage heart failure. Heart failure affects an estimated 5 million patients in the United States. Of those, ≈60% have heart failure with left ventricular dilation and reduced ejection fraction. Trials demonstrating benefit of therapies for heart failure have focused primarily on mild–moderate heart failure with reduced ejection fraction, generally with annual mortality in the range of 8% to 18%.3 Advanced heart failure has been defined as symptoms limiting daily activity (New York Heart Association class III and IV) despite attempted therapy with angiotensin-converting enzyme inhibitors, β-blockers, digoxin, and diuretics,4 a description that applies to ≈300 000 to 800 000 patients in the United States. Although often labeled as “refractory,” many patients enjoy improved quality of life and decreased hospitalizations after referral to experienced heart failure centers, where aggressive medical strategies focus on relief of congestion. Surgical approaches include complex revascularization, valvular repair/replacement, or ventricular reconstruction. When technically successful, biventricular pacing can improve functional status for many of the 25% to 40% of patients with marked ventricular asynchrony.5 If early stabilization allows institution of β-adrenergic–blocking agents, prognosis is further improved.6 Dedicated heart failure management programs that facilitate patient education, compliance, and fluid balance have been integral to benefits observed with these therapies. The highest-risk heart failure populations are best identified after optimization of current therapies. Low left ventricular ejection fraction is not sufficient description of either function or prognosis once heart failure has become advanced. Neither …