Discussion
Contradictory evidence exists in comparison of complications and
all-cause mortality in trials involving off-pump CABG and conventional
on-pump CABG. Meta-analysis performed have shown an increase in
all-cause long-term mortality in patients with off-pump CABG compared to
the traditional modality [11]. A 2014 meta-analysis of more than 20
studies found statistically significant 7% increase in long-term
all-cause mortality with off-pump relative to on-pump CABG [11].
While in 2016, meta-analysis of 100 studies found no difference between
the two techniques when comparing myocardial infarctions and all cause
mortality [15]. A 2018 meta-analysis composed of more than 8000
patients reported higher mortality in OPCABG compared to on-pump CABG
after 4 years or longer post procedure [16]. The population based
evidence aside, each patient’s clinical circumstances warrant a
personalized approach.
There exist alternative strategies to improve outcomes and reduce
peri-operative complications in off-pump coronary artery bypass
grafting. Minimally invasive strategies employed during off-pump CABG,
like minimally invasive direct CABG, have benefits that include faster
recovery and improved results [12]. Percutaneous mechanical
circulatory devices used during off-pump CABG may provide the additional
circulatory support necessary during the necessary intra-operative
cardiac manipulations and anesthesia that decrease cardiac output. Use
of Impella devices have been previously described [13, 14]. Multiple
cases have showed the utilization of Impella 5.0 device during off-pump-
CABG [13, 14]. The Impella 5.0 device utilizes a 21 French pump
motor with peak flow up to 5.0L/min.
The device used on our patient provides up to 3.5L/min of circulatory
support. More important the Impella CP requires only only the insertion
of additional peripheral vascular access via transfemoral approach with
a lower profile system (Impella CP sheath outer diameter 17F,
~4.7 mm) when compared to the larger profile and more
invasive Impella Recover LP 5.0 system.
Novel use of Impella CP with a peak flow rate of 3.5L/min in our case
provided appropriate circulatory support for optimal recovery. Using the
smaller motor size (catheter max outer diameter 14F) along with
decreased power requirement may lead to decreased complications
resulting from the use of Impella devices. Utility of smaller sized pump
may have decreased the incidence of valve dysfunction, thromboembolic
complications thrombosis, ventricular perforation, bleeding and vascular
complications [8]. As this was an off-label use of the Impella
device, caution should be advised prior to repeating our approach and
further research is necessary to advance this burgeoning
multi-disciplinary field.