Use of mechanical left ventricular unloading in acute decompensated systolic heart failure complicated by cardiogenic shock

Acute decompensated heart failure (ADHF) is a serious condition and leading
cause of hospitalization. it carries a high morbidity and mortality. The
average length of hospital stay is approximately 7 to 9 days, 30-day
readmission rate around 20% and up to one in 10 patients dies in hospital,
whereas one in three dies within the year following an hospitalization episode.
Among hospitalized patients with AHF, approximately 15 to 20% have worsening of
heart failure (WHF) with signs of cardiogenic shock during their
hospitalization mandating escalation of therapy. Patients suffering from acuut
heart failure and shock have worse outcomes than those with an uncomplicated
admission for heart failure.
The natural history of HF is a progressive decline in ventricular function as
compensatory remodeling ultimately fails and patients present with recurrent
episodes of AHF and ultimately cardiogenic shock (CS) owing to advanced HF. The
vast majority of AHF (especially acute-on-chronic) episodes are characterized
by increasing symptoms and signs of congestion with volume overload. The goal
of therapy in those patients is the early relief of congestion and to prevent
end-organ damage through organ hypoperfusion. Inotropic support is considered
first-line therapy, although the evidence is relatively scarce. Mechanical
unloading by means of a temporally left ventricle assist device is clinically
practised and forms an alternative approach. On the other hand, invasive
treatment leads to complications. Equipoise exists. An RCT has not been
conducted so far in ADHF patients complicated by cardiogenic shock that
compares the addition of mechanical unloading to pharmacological therapy versus
pharmacological therapy alone.

To assess the efficacy of early mechanical left ventricular unloading and
standard of care (inotropes/vasopressors) versus inotropes/vasopressors alone
(standard-of-care) in patients with ADHF and signs of cardiogenic shock.

Open label, randomized

Mechanical left ventricular unloading with the Impella 5.5 and standard of care
(inotropes/vasopressors) versus standard of care (inotropes/vasopressors)

All decompensated heart failure patients with evidence of cardiogenic shock who
have consented and who are included in the trial will have a clinical
indication for inotropic/vasopressor therapy. Initiation of
inotropes/vasopressors in this specific condition, albeit recommended as
first-line therapy, has been associated with no or only temporary improvement
or even increased overall mortality. As such, this permits an approach in which
a higher level of invasiveness, being mechanical cardiac support, is considered
and can be encouraged. Since there are no randomized controlled trials which
advocate the use of either inotropic/vasopressor therapy or mechanical support
by the Impella 5.5 over one another in this setting, patients will not be
exposed to extra known risk due to randomization in the trial.
Temporary mechanical circulatory support is a widely accepted and applied
treatment modality in high-risk, complex PCI and in the setting of acute
myocardial infarction related cardiogenic shock. In those circumstances the
benefit (reversal of ischemia and cardiogenic shock) is hypothesized to
outweigh the associated complications. The same arguments apply in the setting
of decompensated heart failure with evidence of cardiogenic shock.
Complications, albeit with a reported wide occurrence rate, that are associated
with the use of the Impella 5.5 are: arm ischemia (~0,5%), vascular injury that
may or may not require intervention or surgery (~1,5%), stroke (~2%), infection
of the insertion site (~1%), hemolysis (7-10%) and major bleeds (13% the latter
greatly depending on the thrombolytic regimen applied).
We are aware of the potentially severe adverse events, however the deleterious
clinical condition of decompensated heart failure with signs of cardiogenic
shock, together with the meticulous attention and proper access site management
(surgically) that is being attributed, justifies the application of temporary
mechanical support in our opinion. The benefits outweigh the associated risks.