Date post: | 13-Jan-2016 |
Category: |
Documents |
Upload: | hilary-bradford |
View: | 217 times |
Download: | 4 times |
Transcatheter closure of patent foramen ovale with the SpiderTM PFOOccluder:Initial Clinical Experience
Department of Cardiology ,
Guangdong Cardiovascular Institute
Dr Yigao Huang, Dr Caojin Zhang
Patent foramen ovale (PFO) is quite common, with pr
evalence estimates from 10% to 35% of patients as deter
mined by ultrasound and autopsy studies, respectively.
The prevalence decreases gradually with increasing a
ge, from 34.3% during the first three decades to 20.2% d
uring the ninth decade.
1.Hagen PT, Scholz DG, Edwards WD. Mayo Clin Proc. 1984,59(1):17-20.
3. Fisher DC, Fisher EA, Budd JH,et al. Chest. 1995,107(6):1504-9.
2. Konstadt SN, Louie EK, Black S,et al. Anesthesiology. 1991,74(2):212-6.
4. Stendel R, Gramm HJ, Schröder K,et al. Anesthesiology. 2000 ,93(4):971-5.
Background
Prevalence of PFO is higher in patients with paradoxi
cal embolism and associated with increased risk for recu
rrent thromboembolic events.
The increased risk for recurrent thromboembolic even
ts can be avoided by percutaneous closure of PFO, surgi
cal closure or permanent oral anticoagulation .
1.Taaffe M, Fischer E, Baranowski A,et al. Am J Cardiol. 2008 ,101(9):1353-8.
Transcatheter closure of PFO is a promising alte
rnative to surgical closure or anticoagulation thera
py .
Currently,several devices are used for PFO closu
re, such as Amplatzer occluder , Helex occluder , a
nd CardioSEAL-STARflex occluder.
The aim of the present study was to evaluate t
he safety, feasibility and usefulness for closure of
PFO with a new PFO occluder - the SpiderTM
PFO Occluder(Lifetech Scientific (Shenzhen) C
o.Ltd,China.).
The SpiderTM PFO Occluder
Animal experiment
Material and methods
Guangxi BA-MA Mini-pigs were selected .
(provide by Guangxi University ,Animal technology college)
The fossa ovalis is punctured to establish the animal model of
PFO .
The SpiderTM PFO Occluder was chosen to occlude PFO und
er guidance of fluoroscopy.
After occlusion, mini-pigs were sacrifized at month 1, 2 , 3
and 6 for gross inspection and microscopic inspection.
Puncture right femoro iliac vein after dissection
Position 8 F femoral arterial sheath
Perform pulmonary arterial angiography
Puncture atrial septum and position left atrial wire
Exchange to 10 F long sheath
Position occluder(16 mm)
The procedure of animal experiment
12 Guangxi BA-MA Mini-pigs were sele
cted to complete this experiment.
weight: 28.2 ±3.8 kg
procedure time : 66.75±38.58 min
X-ray exposure time: 22.09±13.38 min
Results
The animal model of patent foramen ovale
The left atrium disc of the SpiderTM PFO Occluder after implantation
The right atrium disc of the SpiderTM PFO Occluder after implantation
The microscopic inspection at 1 month after occlusion
(micro× 100)
The microscopic inspection at 2 months after occlusion
(micro× 100)
The microscopic inspection at 3 months after occlusion (micro× 100)
The microscopic inspection at 6 months after occlusion
(micro× 200)
Results
No vegetation, thrombosis, broken strut, or erosion
was found on the surface of all devices.
The PFOs were completely occluded ,observed by T
TE from 1 to 6 months after occlusion.
The surface of the device was almost fully covered 1
month after occlusion. The left and right discs of the o
ccluder were primarily covered by accretionary collag
enous fibers and endothelial layers which are graduall
y thickening.
Clinical trialClinical trial
Patient Population
Between January 2006 and September 2008
25 patients with a PFO underwent percutaneous PFO closure.
The presence of a PFO was confirmed by transthoracic echoc
ardiography(TTE) and/or transesophageal echocardiography (T
EE) with a spontaneous or provocable (Valsalva manoeuvre) ri
ght-to-left shunt (RLS)
All patients gave written informed consent before the implant
ation procedure.
Degree of right-to-left shunt
Spontaneous or provoked right-to-left shunt was semi-quantitatively graded according to the amount of bubbles detected in the left atrium after crossing the interatrial septum on a still frame:
grade 0 = none,
grade 1 = minimal (1–5 bubbles),
grade 2 = moderate (6–20 bubbles),
grade 3 = severe (>20 bubbles) .The PFO size was additionally determined by multiplane two-dimensional TEE as recently reported by Schuchlenz et al.
Percutaneous PFO closureThe procedure was performed under local anaesthesia. The chosen PFO occluder was mounted on the delivery system and loaded into the transseptal sheath, with care taken to prevent air embolism. The occluder was advanced through the sheath into the left atrium until the left atrial part of the device was unfolded.After that, the whole unit was withdrawn under fluoroscopic and echocardiographic guidance against the interatrial septum. After it was determined that the device was in the correct position, the introducer sheath was further withdrawn, while constant tension was applied on the delivery cable until the right atrial part of the device unfolded. Optimal placement of the device was assured by TTE and the absence of a residual shunt after deployment by color flow Doppler and micro-bubble administration.
Set up the track
The procedure was performed under fluoroscopic guidance
The procedure was performed under echocardiographic guidance
The occluder is well positioned and shaped after the occlusion
Post interventional Treatment
All patients were treated with aspirin 100
mg once daily for 6 months, at which time
the medication was stopped unless required
for another indication.
Follow-Up Evaluation
A two-dimensional TTE, chest X-ray and routine-ECG was performed at 24 hours after transcatheter PFO closure . Patients were followed-up prospectively by TTE and/or TEE and clinically at 24 hours, 1 month, 3 months, 6 months, and 12 months after device implantation and yearly thereafter. Including extensive neurological (by a neurologist experienced in cerebrovascular diseases) and medical examination with a 12-lead ECG and a TTE and/or TEE at rest and during Valsalva-Maneuver. Follow-up events included death, recurrent neurological or peripheral thromboembolic events, and the need of reintervention for significant residual shunt or device malalignment.
Results
25 cases with PFO were diagnosed by TTE or TEE
male : 10cases ; female : 15cases;
mean age 35.1±13.8 years, range, 15 to 56 years
3 patients with brain embolism after more than 4 months
3 patients after thrombolytic therapy for a snake-like thrombus
on PFO
6 patients (2 male,4 female) with a repeated migraine history.
8 patients with platypnea-orthodeoxia syndrome
One patient with decompression sickness
4 cases without any symptoms (by physical examination)
22 patients had an ASD like closure (the catheter passe
d through the PFO directly)
3 patients needed an atrial septum puncture
All 25 cases procedure were successful.
Procedure time ( pass PFO) :37±45min
X-ray exposure time : 17±34min
3 procedure time( AIS puncture) : 153、 90 and 73min,respectively
X-ray exposure time: 121 、 40 and 26 min, respectively
TTE or TEE examination after operation 24 - 48 hours:
The position and shape of the occluders were good
Results
There were no deaths or no complications (i.e. air em
bolism or thromboembolism, bleeding, occluder dislod
gement, infection ,myocardial infarction or others) dur
ing the procedure.
Seven patients had frequent atrial premature beats o
r transient atrial tachycardia during implantation, whic
h terminated medically after implantation.
All patients have completed clinical follow-up at least 6 months(25±11,6-39 months).
No complications
No migraine
Blood examination:
Homocytology shows no abnormality
Renal function shows no abnormality
Liver function is normal
Follow-up
The SpiderTM PFO occluder is the first device made in China.
The SpiderTM PFO occluder have some special characters :
1. Conventional Right Atrial Disc.
2. Left Atrial Disc is a ePTFE membrane with four or six
braided ceramic deposit anchors, which may minimize
risk of thrombus formation.
3.An active link between the Left Atrial Disc and the
Right Atrial Disc allows the Left Atrail Disc to conform
to the anatomy of atrial septum.
Discussion
1.Taaffe M, Fischer E, Baranowski A, et al. Am J Cardiol. 2008,101(9):1353-1358.2.Spies C, Khandelwal A, Timmemanns I,et al. Catheter Cardiovasc Interv. 2008 ,72(7):966-70.
3.Luermans JG, Post MC, Plokker HW,et al. Neth Heart J. 2008 ,16(10):332-6.
The summary conclusion of the present study is tha
t the interventional PFO closure
w ith the SpiderTM PFO occluder is a safe and effecti
ve technique with a high success rate.
Our data is in good agreement with previous studie
s using different transcatheter occluder systems.
SpiderTM PFO occluder is a good choice for a transcath
eter PFO closure
If the catheter passes directly through PFO to create th
e path, a relative small size device can be selected.
If it is difficult for catheter passing the PFO (over 20
minutes) , the method of puncturing the atrial septum s
hould be used, and a relative larger size device will be
selected.
Firstly, our patient population was a selecte
d cohort referred to our institution for percuta
neous PFO closure and might differ from othe
r series published.
Secondly, the number of our patient populat
ion was smaller than other studies’.
Limitations of our study
Conclusion
Transcatheter closure of PFO with the SpiderT
M PFO Occluder is a safe and effective therapeuti
c option .
To further evaluate this strategy, randomized tr
ials comparing this device with other devices an
d therapies have to be performed
Guangdong General hospital