

26
Chapter 2
curves.
12
Two experienced cardiac anaesthetists were assigned to the procedures, with
one only responsible for the study documentation. As the primary end-point the authors
have chosen a surrogate parameter, probably reflecting one aspect of patient outcome:
perioperative cumulative cerebral oxygen desaturation, which was comparable between
groups, as were the results of a secondary endpoint, the neurocognitive function. However,
more respiratory adverse events were registered in the sedation group. Looking in more
detail at the anaesthetic procedure, the author’s state that moderate to deep sedation was
performed to provide optimal implantation conditions. One might question whether we
still can expect a favourable difference in patient outcome between general anaesthesia
and deep sedation? Deep sedation for sure has several disadvantages, as are described in
the respective adverse respiratory events of the present study. But is deep sedation really
needed to facilitate this procedure in an optimal manner? In our centre, TF-TAVI is performed
with reasonable results in unsedated or only light sedated patients.
13
However, these results
might also have signi cant bias, as they come from an observational cohort database and
not from a randomised trial. As in other hospitals, we performed GA in the beginning
and then switched to sedation and later to LA only, after learning our lessons concerning
patient selection, vascular screening, team training, and after gaining more experienced
with the procedure. However, although the TAVI procedures are constantly improved,
all these interventions are associated with potentially life-threatening complications, and
therefore - although the procedure is performed by a cardiologist under local analgesia
– a cardiac anaesthetist is part of the multidisciplinary team. Performing TF-TAVI under
LA without sedation has another advantage: communication with the patient is the best
neurologic monitor we have, and in case of any cerebrovascular event, immediate further
diagnostic and possible treatment strategies can be initiated. This advantage will be lost in
situations where deep sedation is used, as described in the study by Mayr and colleagues.
11
These authors have chosen cerebral desaturation as the primary outcome parameter;
in both groups, cerebral oxygenation decreased during pacing-induced cardiac arrest
for balloon valvuloplasty and hypotension during valve release. However, these periods
of cerebral desaturation were obviously too short to have any effect on neurocognitive
function. The current study is too small to allow a more distinct answer on whether the
respective anaesthetic technique influences patient outcome after TF-TAVI. As most of the
current reviews on this topic conclude, we need randomised trials to de ne the role of
anaesthesia in the treatment of patients with severe aortic stenosis undergoing TF-TAVI.
As the number of patients treated with this technique increases,
14,15
we should be able to
answer this question with evidence-based data from randomised trials. The study from
Mayr and colleagues
11
is a rst step on a long way to further evaluate the optimal treatment
strategies for TF-TAVI. It is attractive for cardiologists and cardiac surgeons to demonstrate
that these procedures can be performed without anaesthesia support. Therefore, we clearly