Background : Because the implantation of a LVAD has resulted in a durable improvement
of the hemodynamic condition of patients with failing heart, we followed an array of
endocrinologic responses taking place during chronic support.
Method and results: In 5 patients with severe heart failure who underwent the
implantation of a Novacor for dilated cardiomyopathy (2), for ischaemic heart disease (2)
and for late cardiac graft failure (1), the serum levels of aldosterone, renin activity, cortisol,
testosterone, thyroid hormones and the urine excretion levels of cathecholamines were
measured. Four patients were successfully transplanted and one patient was weaned from
the device. Mean support time was 153 days (range: 105-175).
Conclusion : The most striking response to chronic mechanical support is a normalization
of the neuroendocrine alterations due to the pre-existing low cardiac output, namely the
stimulation of the renin-angiotensine-aldosterone axis and of norepinephrine release. This
improvement occurs within 2 weeks of support. The debilitated status before the device
implantation is reflected by low T3 and low testosterone levels, which take a longer period
to be normalized.
The normalization of the parameters confirms the restoration of a physiological cardiac
output: this not only would warrant the chronic implantation of a LVAD but would make
of it a possible alternative to heart transplantation.