With the Jarvik 2000 FlowMaker® as its crutch, the failing natural heart can sometimes heal, depending on the nature of what caused it to fail in the first place. In a patient with an acute infection of the heart (myocarditis), healing may mean fighting off the infection and repairing diseased cells. For chronic heart failure patients, healing may mean a process of “reverse remodeling,” whereby the enlarged heart, while supported, contracts and restores itself to a healthier, smaller size and shape. Recovery of the natural heart is not assured, however, and degrees of recovery vary from patient to patient.
Most heart failure patients treated with a VAD see modest improvement in their natural heart, while a few recover completely. This difference is linked to the nature and the degree of their condition. For example, a patient suffering heart failure from myocarditis may be more likely to recover full functioning of the natural heart than a patient suffering, say, permanent damage to the heart muscle due to chemotherapy. The reason is obvious: an infection, while it initiates a rapid decline in heart function, can be fought off before it does irreparable harm. A VAD simply lifts the heart’s load long enough to allow this healing to occur.
Signs of recovery in the natural hearts of nearly all VAD-supported patients are among the most tantalizing of recent findings for doctors who treat heart failure, and such cases have prompted voluminous new literature on the subject.
Clinical experience now supports the claim that VADs can rehabilitate the failing heart. A recent review of research on the topic notes that “at the cell and tissue level, virtually every type of pathologic defect associated with failing human hearts demonstrates changes during LVAD support” and that those changes are for the better.*
Just as heart failure may progress by various mechanisms that weaken and damage the heart, various mechanisms may be involved in healing the damaged heart. Doctors and researchers are homing in on them. While some researchers have looked at the chemical or structural changes that accompany reverse remodeling, others have examined changes in gene expression in the heart tissues. By studying the changes that take place in a heart assisted by a mechanical device, doctors and researchers are learning more about the disease and how to treat it.
*”Reversal mechanisms of left ventricular remodeling: lessons from left ventricular assist device experiments.” Margulies K.B. Journal of Cardiac Failure 2002 Dec (8: S500-5).