Abstracts 4. Gemeinsamer Jahreskongress der ... - SWISS KNIFE

swissknife spezial 06 12.06.2006 13:39 Uhr Seite 49
(p=0.003), and 36% vs 25% in younger patients, respectively (p=0.025). In none of these
analyses the method of revascularization, i.e. open surgical versus endovascular procedure,
was associated with outcome.
Conclusion: Revascularization significantly improves the prognosis of CLI at any age.
Attempts to re-establish a sufficient circulation are therefore mandatory even in patients of 80
years or older. However, no significant differences were found with respect to the choice of
method of revascularization in this series for this age group.
30.03
P. Tozzi 1 , E. Borghi 2 , B. Perrin 3 , G. Siniscalchi 4 , E. Haesler 5 , D. Hayoz 5 , L.K. von Segesser 6
1 Chirurgie Cardiovasculaire, CHUV, 1011 Lausanne/CH, 2 Engineering, Idee & Sviluppo, Bologna/IT,
3 Cardiovascular Surgery, CHUV, Lausanne/CH, 4 Chirurgie Cardiovasculaire, CHUV,
1011 Lausanne/CH, 5 Angiologie, CHUV, Lausanne/CH, 6 Chirurgie Cardiovasculaire, CHUV,
1011 Lausanne/CH
Edge-to-edge vascular repair: a new technique to improve long term anastomosis patency
rate
Objective: The suture technique described more than 100 years ago by Carrel still provides
the best long term results in terms of anastomosis patency, with respect to other suture and
sutureless techniques. Several sutureless anastomosis devices have been designed to facilitate
the surgeon’s work but, almost in all cases, they have failed to reproduce the same long
term results. The Vascular Join (VJ) is a sutureless vascular anastomosis device that has
been designed and developed in our institution to facilitate the anastomosis construction and
eventually improve its patency rate. We designed an animal study to assess its reliability and
long-term efficacy and we report the preliminary results.
Methods: Device description: VJ allows the construction of end-to-end and end-to-side anastomoses.
It consists of two metallic crowns fixed to the extremity of the two conduits so that vessel
edges are joined layer by layer. There is no foreign material exposed to blood. Animal
model: in adult sheep, 45 to 55 kg, equipped with femoral arterial line, both carotid arteries
were prepared and severed. After injection of heparin 100 U/kg, end-to-end anastomoses
were performed using the VJ device on one side and the classical running suture technique
with 6-0 prolene on the other side. Carotid blood flow was measured with Medistim probe.
Animal received aspirin 100 mg/day and were followed-up with Duplex-scan every 3 months
and sacrificed after 12 months. Hystopathological analysis was carried out.
Results: Sixteen animals were enrolled and all survived the procedure. A total of 16 sutureless
anastomeses were successfully completed in less than 2 minutes versus 6±3 min for running
suture. Mean post operative carotid flow was 180±46 ml/min on the sutureless side and
163±36 ml/min in the control side. Duplex showed the occlusion at 3 months of 3 controls
and one sutureless anastomosis. 2 controls and 1 sutureless had stenosis >50% at 12
months. Histology showed very thin layer of myointimal hyperplasia (50±10 mm) in the sutureless
group versus 300±27 mm in the control. No significant inflammatory reaction was
detected.
Conclusion: VJ provides edge-to-edge vascular repair that can be considered the most physiological
way to restore vessel continuity. For the first time, in an animal study with long term
follow up, an anastomotic device provided better results than suture technique. Clinical trial is
about to start to validate these results.
30.04
H. Probst 1 , F. Huot 2 , S. Déglise 3 , C. Haller 4 , L. Mazzolai 5 , F. Saucy 1 , F. Bosman 6 , J. Corpataux 7
1 Service De Chirurgie Thoracique et Vasculaire, Centre Hospitalier Universitaire Vaudois, 1011
Lausanne/CH, 2 Bioengineering, MachineVision, 1011 Lausanne/CH, 3 1012 Lausanne/CH,
4 Thoracic and Vascular Surgery, CHUV, 1011 Lausanne/CH, 5 Service D'angiologie, Centre Hospitalier
Universitaire Vaudois, 1011 Lausanne/CH, 6 Institut De Pathologie, Centre Hospitalier
Universitaire Vaudois, 1011 Lausanne/CH, 7 Vascular and Thoracic Surgery, CHUV, 1011
Lausanne/CH
Comparative assessment of continuous and pulsatile ex-vivo perfusion of human saphenous
vein after 14 days
Objective: Vessel wall trauma induces vascular remodeling, as intimal hyperplasia (IH) and
subse-quent thrombotic occlusions, compromising vascular reconstructions. Plasminogen
activator system might precociously induce a prothrombotic state in the vein graft associated
with stenosis development. Ex-vivo perfusion of human vessel segments is a well-suited setting
to assess venous segments regarding vessel wall remodeling and fibrinolytic alterations.
Methods: The ex-vivo vein support system (EVVSS) consists of an incubator containing a perfusion
chamber and a gearing pump. This setting allows to perfuse vessel segments with a
continous flow under low shear stress conditions. This perfusion system modified to produce
pulsatile flow by an arbitrary waveform generator controlled by computer is under high shear
stress conditions. Both systems maintain a constant perfusate temperature (37°C±0.l°C),
pCO2 (35-45mmHg), pO2 (90-110mmHg) and pH (7.41±0.05). Human saphenous vein
segments are perfused in both settings under constant conditions (pressure, flow, shear
stress) during 14 days. We performed computer-assisted histomorphometry, immunohistochemistry
(CD 31, CD 34, Factor VIII, MIB 1, alpha-actin) and expression of fibrinolytic factor
(t-PA, u-PA and PAI-l by Northern blot) before and after perfusion on each segment.
Results: Nine human saphenous vein segments were perfused for 14 days, with respect of
their morphological integrity. Histomorphometry revealed significant IH development in the
continuous perfusion system after 14 days. No IH development was observed in the pulsatile
system. Expression of CD31, CD34 and alpha actin was demonstrated in all segments after
culture and perfusion indicating muscular and endothelial integrity in both groups. We observed
an upregulation of PAI-1 in both settings after 14 days.
Conclusion: Vessel wall integrity is maintained in the ex-vivo continuous and pulsatile flow
perfusion. The continuous flow is a valid setting for the assessment of IH under standardized
conditions. The pulsatile flow conditions inhibits IH development under high shear stress conditions.
30.05
A. Assadian, C. Senekowitsch, G.W. Hagmüller
I. Chirurgie, Wilhelminenspital Vienna, A-1160 Vienna/AT
Prevalence of patients continuing to smoke after vascular interventions
Objective: Smoking is one of the most important risk factors for the development and progression
of atherosclerosis. Smoking cessation presents an obligatory element in the manage-
ment of vascular patients and also in patients scheduled for vascular interventions. The aim
of this study was to assess the prevalence of patients smoking before and after vascular surgical
procedures and to evaluate the requirements for inpatient smoking cessation programs
and nicotine replacement therapy.
Methods: 500 patients admitted for vascular interventions were included in this prospective
study. Smoking status was evaluated as well as measurements of exhaled breath CO;
patients had to answer a standardized Fagerström questionnaire on admission and after surgery
to identify current smokers and to quantify nicotine dependency, respectively.
Results: of 500 patients included, only 70 (14%) never had smoked, 243 (49 %) had quit
smoking before admission and 161 (32%) were current smokers. of the current smokers 64
(40%) did not smoke during hospitalization. 97 (60%) current smokers continued to smoke
in hospital. of these patients, 78 patients (80%) were male and 19 female; the mean age was
61 ± 4 years (range 40 84 years). 4 patients had surgery of infra-renal aortic aneurysm, 40
patients had carotid endarterectomy and 53 patients had PAD. There was no difference between
abstinent patients and continuing smokers concerning previous cigarette consumption
or Fagerström score, a predictor for long term smoking behavior. Patients with carotid artery
stenosis were significantly more abstinent while hospitalized (P=0.006). Patients with PAD,
however, were more likely to continue smoking as inpatients (P=0.004). 65% of continuing
smokers stated that they would stop smoking in hospital if counseling and nicotine replacement
therapy would be provided. Regarding their predominant location of atherosclerosis,
patients with PAD were less willing to quit smoking while hospitalized compared to patients
with carotid stenosis (53% vs 88%, respectively; P < 0.001).
Conclusion: A substantial fraction of patients admitted for vascular surgery are smokers.
More than half of these continue to smoke in the hospital, an environment where smoking is
prohibited by law. Counseling, nicotine replacement therapy as well as smoking cessation
programs for vascular surgical inpatients is urgently needed.
30.06
S. Déglise 1 , C. Haller 2 , H. Probst 3 , S.D. Qanadli 4 , J. Corpataux 3
1 1012 Lausanne/CH, 2 Thoracic and Vascular Surgery, CHUV, 1011 Lausanne/CH, 3 Vascular
and Thoracic Surgery, CHUV, 1011 Lausanne/CH, 4 Radiology, CHUV, 1011 Lausanne/CH
Is the use of the great saphenous vein a suitable alternative for arteriovenous fistulas creation
in the upper limb?
Objective: Failure or non-maturation of arteriovenous fistulas for haemodialysis access
remains relatively frequent although preoperative assessment of forearm superficial venous
system has been developped. Moreover, increasing the prevalence of arteriovenous fistula
over synthetic graft is critical for decreasing the morbidity of these patients. Therfeore, the
great saphenous vein could be an alternative when no suitable veins exist on the arm.
Methods: Between August 2000 and September 2003, 12 patients underwent arteriovenous
fistulas creation on the forearm for haemodialysis access. They were 10 men and 2 women
with a mean age of 58 years (range 35-80). In all these patients but 2, one or more arteriovenous
fistula had been previously created and failed. Data were reviewed to analyze the evolution
of these fistulas in terms of blood flow, stenosis or patency rates.
Results: The technical success was 92% (11/12) because in one patient, the fistula was
rapidly oc-cluded leading to the use of a dialysis catheter. The mean blood flow measured in
the 11 matured fistulas was 836 ml/min. In 5 patients, 12 stenoses occurred during the follow-up,
the first stenosis appearing on average after 10 months. Seven (58%) of them were
succesfully treated by angioplasty. Two surgical revisions were also necessary and in the 3
remaining cases, a new prostethic fistula was created. Moreover, 2 occluded fistulas were
successfully treated by surgical thrombectomy and one dilated fistula justifyied its surgical replacement.
One patient with an occluded fistula died due to gastrointestinal sepsis. Overall
primary, assisted primary and secondary patency rates were 33%, 42% and 50% respectively.
Conclusion: The use of a saphenous vein for arteriovenous fistulas creation on the forearm
seems to show low patency rates and high frequency of complications especially stenosis.
Therefore, this procedure should be kept in reserve only for very specific conditions as presence
of infection.
30.07
H.O. Savolainen 1 , J. Schmidli 2 , F. Dick 3 , I. Bau mgartner 2 , M. Mohaupt 4
1 Vascular Surgery, Swiss Cardiovascular Center, 3010 Bern/CH, 2 Swiss Cardiovascular
Centre, Uni-versity Hospital, Bern/CH, 3 Swiss Cardiovascular Centre, University Hospital, 3010
Bern/CH, 4 Departement of Nephrology, University Hospital, Bern/CH
Determinants of hemodialysis access survival
Objective: Vascular access patency is vital for patients requiring hemodialysis. Various factors
interfere with access patency. This analysis is projected to validate potential risk factors
and benefits including unintended impact of co-medication.
Methods: Hemodialysis access procedures between January 1999 and December 2001
were retro-spectively analysed. Clinical data and concomitant medication were retrieved from
files as were surgical data following a standardized data capture sheet. Minimal required follow-up
with functioning access was 2 years.
Results: During the observation period, 244 vascular accesses were created (60.7% male
patients, 36.1% pre-emptive) with 102 remaining primarily patent. Censored (death, transplantation,
access termination) primary (PP) and secondary patency (SP) was 54.6% and
71.7%, respectively, at 540 days. Patency of permanent cuffed catheters was lowest due to
censoring events. Diabetes mellitus reduced PP (p