Implantation of a left ventricular assist device (LVAD) is an established treatment
for end-stage heart failure. Right ventricular (RV) dysfunction develops in 20% to
50% of patients after LVAD implantation, leading to prolonged ICU stay and elevated
mortality. However, the prediction of RV failure remains difficult.
The pre-operative echocardiographic parameters, tricuspid incompetence (TI), RV end-diastolic
diameter (cut-off >35 mm), RV ejection fraction (cut-off <30%), right atrial dimension
(cut-off >50 mm) and short/long axis ratio (cut-off >0.6), were analyzed retrospectively
in 54 patients. Patients were divided into two groups. One group consisted of patients
with RV failure (n = 9), as defined by the presence of two of the following criteria
in the first 48 hours after surgery: mean arterial pressure < or =55 mm Hg; central
venous pressure > or =16 mm Hg; mixed venous saturation < or =55%; cardiac index <liters/min/m(2);
inotropic support score >20 units; or need for an RVAD. The other patients comprised
the non-RV-failure group (n = 45).
The RV failure group had a significantly higher short/long axis ratio of the RV (0.63
vs 0.52, p = 0.03; odds ratio 4.4, p = 0.011). For patients with a short/long axis
ratio of the RV of <0.6, RV failure occurred in 7% of patients, as compared with 50%
for patients with a ratio > or =0.6 (p = 0.013). Among patients with TI Grade III
or IV, 75% developed RV failure as compared with 12% in patients with TI Grade I or
II (p = 0.054). The odds ratio for RV failure after LVAD implantation for TI Grade
III or IV was 4.7 (p = 0.012).
Pre-operative evaluation of tricuspid incompetence and RV geometry may help to select
patients who would benefit from biventricular support.