Introduction
Left ventricular assist device (LVAD) therapy confers both a survival
and quality of life benefit for advanced heart failure
patients.1 LVADs have standardly been implanted via
full median sternotomy,2 but the smaller size of newer
centrifugal pumps has facilitated the use of less invasive,
sternal-sparing techniques, either via bilateral thoracotomies or upper
hemi-sternotomy with left thoracotomy.3–5Non-sternotomy LVAD implantation techniques have been shown to be safe
and effective when both HeartwareTMHVADTM (Medtronic, Minneapolis,
MN)6,7 and Heartmate 3TM (HM3)
(Abbott, Chicago, IL)8,9 devices are used, and they
have demonstrated lower rates of right ventricular failure, blood
product transfusions, and lengths of hospital stay by comparison.
Several advantages of sternal-sparing approaches compared to sternotomy
have been proposed. There may be less risk of right heart failure, a
common complication after LVAD implantation,10 because
the pericardium over the right ventricle is
preserved.8 With the heart maintained in anatomic
position, there is less potential for pulmonary artery obstruction and
coronary hypoperfusion.8 Additionally, better
visualization of the apical inflow anastomosis and assessment of
hemostasis are afforded, and the sternum is spared for more easy sternal
entry if the patient is to move forward with heart transplantation
following LVAD implant. Finally, without sternal restrictions, patients
can begin more prompt physical therapy after surgery, which is
beneficial for rehabilitation in both bridge-to-transplant and
destination therapy patients.8
In addition to improvements in newer LVAD generations and development of
new implantation techniques, inflow cannula angulation has also been
tied to patient outcomes. In HVAD patients, Imamura et al.associated smaller cannula coronal angles with improved left ventricular
unloading,11 leading to improved myocardial structural
and functional parameters that help prevent heart failure
recurrence.12 Furthermore, angles ≤65° were associated
with reduced heart failure readmission rates.11 Prior
work has also suggested that inflow cannula angles after LVAD
implantation can be more consistently reproduced with a sternal-sparing
approach, compared to median sternotomy.13
Increasing adoption of sternal-sparing approaches to LVAD implantation
underscores the need for individual institutions to illustrate their
experience and patient outcomes using these techniques. The purpose of
this study is to compare both inflow cannula angles and postoperative
outcomes for patients who received LVAD implantation by either median
sternotomy or bi-thoracotomy (BT).