4. Discussion
Multiple non-randomized studies, meta-analyses and registry have shown
that Sutureless rapid deployment aortic tissue valve is safe and
effective alternate to conventional SAVR and associated with improved
clinical outcomes.
In majority of published studies on Perceval valve, the average age of
patient was > 75 years, where as in our study the average
age was 67.3 ± 13.8 years. Major advantage of Perceval sutureless valve
was observed in intermediate and high risk group (15,16) whereas in our
study all patients were in low or intermediate risk group with average
STS score of 2.71 ± 1.54.
Various studies have demonstrated that duration of aortic x-clamp and
CPB are independent predictors of survival after valve replacement and
combined valve operation with CABG (17). In our study the average
x-clamp time of 42 ± 11 minutes in isolated aortic valve and 74 ± 23
minutes in combined procedures. The CPB time was 54±14 minutes in
isolated AVR and 101±36 in combined procedures. We observed 18%
reduction in x-clamp time and 22% reduction in CPB time when we
compared it with standard bio-prosthetic sutured valve by same surgeon.
In CABG + AVR patient all distal anastomosis were done on pump beating
heart which further reduced the x-clamp time.
Recently published Persist AVR trial has shown 30% reduction in x-clamp
time and 20-25% reduction in CPB time by using Perceval in comparison
of standard AVR in isolated AVR surgery (18).
In our experience we could perform MIAVR in 12 out of 19 isolated AVR
patients. In SURD-IR registry it was observed that less invasive
approach was used in two third of study patients and in 50% high risk
patients, with good intermediate results in all risk categories (19).
In our study also we did not find any significant difference in x-clamp
and CPB time between sternotomy AVR and MIAVR with use of Perceval, but
the patient number are less to reach to a real conclusion.
There was no PVL in any of our patients. The vast majority of published
reports shown very low rate of moderate to severe PVL (21) with proper
decalcification, sizing and valve positioning, PVL is comparable with
standard SAVR (14).
The rate of permanent pacemaker implantation has been a bit of concern
with the Perceval. The majority of the literature reports of PPI between
6% and 9%. However some studies have reported rate as high as 23%
(22). In order to avoid PPI, the key points are (i) proper
decalcification of the annulus, (ii) correct sizing and certainly avoid
over sizing, (iii) proper placement of guiding sutures, (iv) Adjusting
balloon inflation between 2to 4mmHg (15), by using these modified
guidelines we have noticed significant improved in rate of PPI.
4 patients developed new onset LBBB in immediate post-operative period.
In two patients, it was recovered to normal EKG in ICU where as in 2
patients it was persisted in follow-up. One patient with preexisting
RBBB had complete heart block in immediate post-operative period
requiring temporary pacing but it was recovered on 6thpost-operative day. 2 patients developed new onset LBBB post implant
which was persistent during follow-up. We had 2.4 ± 1.1 and 3.9 ± 1.6
days ICU stay and 6.7 ± 1.2 and 10.9 ± 2.4 days hospital stay in
isolated AVR and combined procedure respectively. In these small number
of patients we did not find much difference in ICU and hospital stay
when compare to standard sutured aortic valve. Multiple studies have
reported decrease in ICU stay and blood transfusions with use of
Perceval sutureless valve in isolated AVR (23). Marco Solinas et al
reported reduction of ICU and hospital stay by adding Perceval valve and
right anterior thoracotomy(20). In an international prospective registry
statistically significant difference was noticed in ICU and hospital
stay by using sutureless valve and MIAVR approach (24).
Rate of intraoperative stroke range from 0 to 5% for the Perceval and
2.5 to 5% for TAVI (26, 27). Data from Partner II trial and German
registry indicates that the incidence of PVL after TAVI is significantly
higher when compared with Sutureless aortic valve (28). SURD-IR registry
has shown that in low risk patients, the mortality rate was lower in
sutureless valve then that recorded in the NOTION trial 1.55 vs 2.1%
(29). The most important piece of data concerns to patients deemed at
very high risk, a patient population comparable to that included in the
PARTNER trial cohort B (6). In this trial in hospital mortality was 2
fold higher than that observed in SURD-IR registry for sutureless valve
(2.6% vs 5%) (19).
In two female patients with small aortic annulus, small size Perceval
valve was implanted. Both patient showed excellent valve hemodynamics in
post-operative period with no patient prosthesis mismatch.
In our limited experience, morbidity was low and we did not have any
mortality even in follow-up. SURD-IR registry has compared the morbidity
and mortality in patients undergoing sutureless rapid deployment valve
and they found a extremely satisfactory results even in high risk (EURO
score > 10 - 20%) and very high risk (EURO score
> 20%) patients (19).
We noticed stable hemodynamics and satisfactory gradient in all our
patients at 6 months and 1 year follow-up and none of our patient
developed central or PVL.
The health economics of Perceval sutureless valve is highly dependent on
the healthcare system, however the ability to facilitate MI surgery will
enhance its cost effectiveness by reducing ICU stay, hospital stay and
blood usage. Especially in high risk patients using sutureless valve
instead of TAVI will further reduce the prosthesis cost (11).