Insert your Title here
Put your Name here eg :
Antonios Kallikourdis1 and Samuel Jacob1 Joel Dunning2
Insert your institution here e.g. :
1. Department of Cardio-thoracic Surgery, Aberdeen Royal Infirmary, Aberdeen, AB25
2ZN, UK
2. Department of Cardiothoracic Surgery, James Cook University Hospital ,
Middlesbrough, UK
Put your contact details here:
Corresponding Author:
Joel Dunning
Department of Cardiac surgery
James Cook University Hospital
Middlesbrough, UK
E-mail: joeldunning@doctors.org.uk
Tel/fax: +44-7801-548122
Word count : 1000
Summary
A best evidence topic in cardiac surgery was written according to a structured protocol. The
question addressed was Insert your question here. Altogether more than ____ papers were
found using the reported search, of which ____represented the best evidence to answer the
clinical question. The authors, journal, date and country of publication, patient group
studied, study type, relevant outcomes and results of these papers are tabulated. We
conclude that Insert your findings here, this is usually identical to your clinical bottom line
at the end of the paper and you can cut and paste the clinical bottom line here if you wish
Key Words: review; Take MeSH words from the search strategy if you can
1- Introduction
A best evidence topic was constructed according to a structured protocol. This is fully
described in the ICVTS [1]
Don’t edit this and remember to keep reference 1 in
2- Three-part question
Have a go at this if you wish or I will do it: example:
In [patients undergoing a bioprosthetic aortic valve replacement] is [a stented or a stentless
valve] superior [for achieving left ventricular recovery]
3-Clinical scenario
Feel free to add one of these in or I will do it.
You are at a national conference hearing about the benefits of a stentless aortic valve over a
conventional stented valve. An eminent speaker from the floor then stands up and contends
that there have been no definitively proven benefits for stentless valves. He continues to say
that as the implantation time in these older patients is significantly higher with an
associated increase in morbidity, that those who implant stentless valves outside of a
clinical trial are similar to cardiologists who implant coronary stents outside of published
national guidelines, and both practises should be discontinued. You resolve to check the
literature yourself.
4- Search strategy
Have a go at this if you like, but I usually do this or edit it heavily, so you can also leave it if
you prefer
Medline 1950 to May 2007 using OVID interface
[aortic valve replacement.mp OR exp aortic valve/] AND [Stentless.mp OR Stented.mp]
5- Search outcome
_____ papers were found using the reported search. From these ____ papers were
identified. That provided the best evidence to answer the question. These are presented in
table 1.
6-Results
Insert your results here AFTER you have added all your chosen papers to the table. We
usually go straight in and discuss all or most of the papers and then come to conclusions. You
only have 1000words for the whole paper from the Introduction to the Clinical bottom line
and thus words are tight. You do not need to do a preamble or background information.
Knowledge of the subject should be assumed.
Here is an example that you should delete:
Kunadian et al [2] in 2007 performed a meta-analysis of all the randomised controlled trials
that we identified. They found that the effective orifice area and the mean and peak aortic
valve gradients were significantly superior to the conventional stented valves used as
controls across the 10 studies.
In addition they showed that at 6 months the left ventricular mass index reduced
significantly more in the stentless valve group. However by 12 months the patients in the
stented valve groups had caught up with the stentless valve groups in terms of mass
regression and there was no longer a significant difference. No mortality or symptomatic
benefits were demonstrated.
They also aggregated the times taken to perform the 2 types of operation. Overall there was
a mean increase in the cross clamp time of 23 minutes and a 29 minute increase in the
bypass time.
Ali et al [3] showed that, both stented and stentless bioprosthesis are associated with
excellent clinical and haemodynamic outcomes 1 year after AVR. Comparable
haemodynamic and LVM regression can be achieved using a second-generation stented
pericardial bioprosthesis. However, in patients with reduced ventricular function
preoperatively (left ventricular ejection fraction [LVEF] <60%), there was a significantly
greater improvement in LVEF from baseline to 1 year in stentless valve recipients.
Perez et al [4] studied left ventricular mass index (LVMI) measured by transthoracic
echocardiography and, in a subset, cardiovascular Magnetic Resonance (MR).
Measurements were taken before valve replacement and at 6 and 12 months. There was a
greater reduction in peak aortic velocity (P<0.001) and a greater increase in indexed
effective orifice area (P<0.001) in the stentless group than in the stented group. There were
no differences in clinical outcomes between the 2 valve groups after one year
Bakhtiary et al [5] compared coronary perfusion after aortic valve replacement with stented
or stentless porcine bioprosthesis. Coronary flow increased in both groups significantly
(P<.001) after aortic valve replacement. This increase was higher in the stentless group
compared with that seen in the stented group (343 +/- 137 vs 221 +/- 66 mL/min). Left
ventricular mass regression was similar in both groups.
Totaro et al and Santini et al [6, 12] targeted old patients (>70 years old) and found that the
improved design of the recently introduced third-generation stented bioprosthesis allows
implantation of a significantly bigger valve than with the old generation which was similar in
function to a stentless valve.
On the other hand Doss et al [7] found that previously reported findings, faster and more
complete regression of left ventricular mass and haemodynamic benefits of stentless valves
were not reproducible
Cohan et al [8] studied echocardiographic measurements and functional status (Duke
Activity Status Index) assessed at 3 and 12 months. They found that perioperative morbidity
and mortality was similar between groups at 12 months postoperatively. Cardiopulmonary
bypass times (CE: 118.6+/-36.3 minutes; SPV: 148.5+/-30.9 minutes; p = 0.0001) and aortic
cross-clamp times (CE: 95.4+/-28.6 minutes; SPV: 123.6+/-24.1 minutes; p = 0.0001) were
significantly prolonged in the SPV group,
Maselli et al [9] studied the effect of four different types of prosthetic aortic valves on time
course and extent of regression of left ventricular hypertrophy. They found that stentless or
homograft aortic valve produces more complete or at least faster regression of left
ventricular hypertrophy.
The same result was achieved by Walther et al [10]. They found that regression of left
ventricular hypertrophy occurs in all patients after aortic valve replacement but is enhanced
after stentless valve implantation.
Williams et al [11] studied left ventricular mass using magnetic resonance imaging (MRI) at 1
week, 6 months, and 32 months. At 32 months, measurement in diastole showed a
reduction of 38% (P<.01) in the stentless group compared with 20% (P = ns) in the stented
group, and measurements in systole showed a 23% (P<.01) and 13% (P = ns) reduction,
respectively. This study confirms that a larger stentless valve can be implanted into a given
size of aortic annulus with superior residual aortic valve gradients.
7. Clinical bottom line
This should be a quick and catchy clinical bottom line, hopefully with strong
recommendations. I really don’t like the words ‘further research is needed’, please just
make a conclusion based on your Best Evidence.
You can cut and paste this into the conclusion of the abstract
Here is an example
Stentless valves allow a larger effective orifice area valve to be implanted with a lower mean
and peak aortic gradient post-operatively. At 6 months several studies and a meta-analysis
have shown superior left ventricular mass regression in the stentless valve groups. However
by 12 months the stented valve groups catch up in terms of mass regression and this
significance disappears. No clinical benefits in terms of symptoms or mortality have so far
been shown. On average a stentless valve requires a 23 minute longer cross-clamp time and
a 29 minute longer bypass time.
References
References should go before the table. Make sure that all authors are included and not just
the first 3 or 6 wih an et al. The format is as below :
[1] Dunning J, Prendergast B, Mackway-Jones K. Towards evidence-based medicine in
cardiothoracic surgery: best BETS. Interact CardioVasc Thorac Surg 2003;2:405-409.
[2] Kunadian B, Thornley AR, de Belder MA, Hunter S, Kendall SWH, Graham R, Stewart M,
Thambyrajah J, Dunning J. A Meta-Analysis of Valve Haemodynamics and Left Ventricular
Mass Regression for Stentless Versus Stented Aortic Valves. (Ann Thorac Surg ; accepted for
publication March 2007)
[3] Ali A, Halstead JC, Cafferty F, Sharples L, Rose F, Coulden R, Lee E, Dunning J, Argano V,
Tsui S. Are stentless valves superior to modern stented valves? A prospective randomised
trial. Circulation 2006;114:I535– 40.
[4] Perez de Arenaza D, Lees B, Flather M, Nugara F, Husebye T, Jasinski M, Cisowski M,
Khan M, Henein M, Gaer J, Guvendik L, Bochenek A, Wos S, Lie M, Van Nooten G, Pennell D,
Pepper J,. Randomised comparison of stentless versus stented valves for aortic stenosis:
effects on left ventricular mass. Circulation 2005;112:2696 –702.
[5] Bakhtiary F, Schiemann M, Dzemali O, Wittlinger T, Doss M, Ackermann H, Moritz A,
Kleine P. Stentless bioprosthesis improve postoperative coronary flow more than stented
prostheses after valve replacement for aortic stenosis. J Thorac Cardiovasc Surg
2006;131:883– 8.
[6] Totaro P, Degno N, Zaidi A, Youhana A, Argano V. CarpentierEdwards PERIMOUNT Magna bioprosthesis: a stented valve with stentless performance? J
Thorac Cardiovasc Surg 2005; 130:1668 –74.
[7]. Doss M, Martens S, Wood JP, Aybek T, Kleine P, Wimmer Greinecker G, Moritz A.
Performance of stentless versus stented aortic valve bioprosthesis in the elderly patient: a
prospective randomised trial. Eur J Cardiothorac Surg 2003;23:299 –304.
[8]. Cohen G, Christakis GT, Joyner CD, Morgan CD, Tamariz M, Hanayama N, Mallidi H,
Szalai JP, Katic M, Rao V, Fremes SE, Goldman BS. Are stentless valves haemodynamically
superior to stented valves? A prospective randomised trial. Ann Thorac Surg 2002;73:767–
75.
[9]. Maselli D, Pizio R, Bruno LP, Di Bella I, De Gasperis C. Left ventricular mass reduction
after aortic valve replacement: homografts, stentless and stented valves. Ann Thorac Surg
1999;67:966 –71.
[10]. Walther T, Falk V, Langebartels G, Kruger M, Bernhardt U, Diegeler A, Gummert J,
Autschbach R, Mohr FW. Prospectively randomised evaluation of stentless versus
conventional biological aortic valves: impact on early regression of left ventricular
hypertrophy. Circulation 1999;100(19 suppl): II6 –10.
[11]. Williams RJ, Muir DF, Pathi V, MacArthur K, Berg GA.. Randomised controlled trial of
stented and stentless aorticbioprotheses: hemodynamic performance at 3 years. Semin
Thorac Cardiovasc Surg 1999;11:93–7.
[12]. Santini F, Bertolini P, Montalbano G, Vecchi B, Pessotto R, Prioli A, Mazzucco A.
Hancock versus stentless bioprosthesis for aortic valve replacement in patients older than
75 years. Ann Thorac Surg 1998;66:S99 –103.
You should always start doing your paper here. Don’t do anything else until the table is
finished.
With regard to the table do not cut and paste long passages from the abstract. Try to find
the key 1 to 4 outcomes, then put in the actual figures that the papers report. Try not to use
the words X was significantly higher than Y.
Try to say
X mean 34 , SD 20,
Y mean 40 SD 10,
p=0.43
Obviously if you are putting in a guideline you will have to put in their text. This is okay.
Any queries just fill in the table and put in a query in red and send it to me
Cut out the example date here and paste your own in:
Table 1: Best Evidence Papers
Author, date Patient group
and country,
Study type
(level of
Evidence
Dunning et
Ten studies were
al, 2007
identified that
Ann Thorac
included 919
Surg
patients in which
UK [2]
the Freedom
(Sorin Biomedica
Meta analysis Cardio,
(level 1a)
Via Crescentino,
Italy), Freestyle
(Medtronic,
Minneapolis,
MN), Prima Plus
(Edwards Life
Sciences,
Irvine, CA) and the
Toronto and
Biocor (St Jude
Medical, St. Paul,
MN) valves were
used
Outcomes
Key results
Comments
- Peak
gradient postoperatively
Stentless valve mean
difference 5.80mmHg
(4.69 to 6.90) better
than stented valves
At 6 months
Weighted mean
difference; 6.42, [95%
CI 1.21 to 11.63] in
favour of stentless
valve
This meta-analysis
showed that
stentless
aortic valves
provide an
improved level of
left ventricular
mass regression at 6
months, reduced
aortic gradients,
and an improved
effective orifice area
index, at the
expense of times
that were 23
minutes longer for
cross clamp and a
29 minutes longer
for bypass. this
improvement
disappeared
after 12 months
Left
ventricular
mass index
Cross clamp
time
Bypass time
12 months WMD, 1.19;
[95% CI, -4.15 to 6.53],
no significant
difference
Cross clamp time 23
min longer
Bypass time 29 mins
longer