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| Journal of the New Zealand Medical Association,
05-September-2008, Vol 121 No 1281
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Percutaneous transcatheter obliteration of aortic
paravalvular leak
Ali Khan, Peter N Ruygrok, Paisan Nakpathomkun, Ivor L
Gerber
A 76-year-old man with symptomatic severe aortic stenosis
and coronary disease underwent elective aortic valve replacement (AVR) and
two-vessel coronary bypass surgery. During surgery his aortic valve was noted to
be severely calcified, particularly in the right coronary and non-coronary
sinuses, where it was difficult to achieve complete decalcification.
A 29 mm bovine pericardial prosthetic valve was implanted.
The post-bypass transoesophageal echocardiogram (TOE) identified a small
paravalvular leak (PVL) in the region of non-coronary sinus where most
calcification had been observed. At the time it was felt that further surgical
intervention was unlikely to be beneficial.
The patient reported no noticeable improvement of his
pre-surgical dyspnoea (NYHA class III) at the 2-month follow-up visit and a
prominent aortic early diastolic murmur was audible. A transthoracic
echocardiogram showed at least moderate eccentric aortic regurgitation. A
subsequent TOE revealed a significant PVL but no valvular regurgitation and the
left ventricle appeared to have enlarged.
The patient was re-discussed at the combined
cardiology-cardiac surgery meeting and it was felt that the chance of
significant morbidity and mortality, associated with re-operation was high, and
the potential for benefit doubtful. After discussion with the patient, an
attempt to partially obliterate the PVL by a percutaneous transcatheter approach
was planned.
The procedure was undertaken under general anaesthesia with
TOE and fluoroscopic guidance, preceded by DC cardioversion of atrial
fibrillation (AF) to sinus rhythm. Via a retrograde approach from the right
femoral artery, a 6 French delivery sheath was advanced across the defect,
through which a 10 mm Amplatzer vascular plug was carefully positioned and
delivered, with definite angiographic and echocardiographic reduction in the
degree of aortic regurgitation (Figure 1). The procedure time was 55 minutes and
fluoroscopy time 8 minutes.
The patient tolerated the procedure well with no
complications and was discharged the next day on warfarin anticoagulation for
recurrent AF. At 6-week follow-up he reported definite symptomatic improvement
(NYHA Class II) and a TOE showed stable position of the plug with only a
mild-moderate residual PVL (Figure 2).
DiscussionEarly para-prosthetic leakage after AVR is relatively common
and may be related to particular valve types,1
but the majority of defects are small and generally have a benign course. Some,
however, may cause progressive left ventricular dilatation and heart failure
from a high regurgitant load, and may also cause haemolysis. This usually occurs
due to incomplete apposition of the sewing ring of the prosthetic valve to the
native aortic tissue and suture dehiscence, and develops more commonly in
patients with significant annular calcification or localised
infection.1,2
The rate of detection of PVL has increased due to improved
diagnostic techniques. Doppler echocardiography is particularly useful in
differentiating transvalvular from paravalvular
regurgitation.3 Until recently, management has
been limited to medical therapy or re-operation which has been associated with a
high mortality and substantial risk of recurrent paravalvular
leak.4
Percutaneous transcatheter closure of aortic prosthetic PVLs
has recently been described in selected patients, with a reasonable chance of
success. This can however be technically challenging, with only a few case
reports in the literature.5,6 Careful
assessment of the defect by pre-procedural TOE and peri-procedural selective
contrast injection is important in the estimation of defect size and geometry,
and in selection of an appropriate obliteration device.
The presence of vegetations or thrombus, active infection or
an unstable rocking valve, are clear contra-indications. Obliteration of PVL is
feasible in patients with a ‘tilting-disc’ mechanical valve provided
care is taken to ensure the device does not interfere with leaflet movement
before released. No specifically designed transcatheter device has been
developed or approved for percutaneous PVL closure but there are reports of use
of the Amplatzer atrial septal occluder, Rushkind umbrella, Cardioseal Clamshell
septal occluder, and Gianturco detachable
coils.7–9 Larger defects may require more
than one device.
In our case we used the Amplatzer device since it is
compressible and relatively conformable. Potential procedural complications
include interference with valve leaflet movement, embolisation of thrombus, air,
atheroma or the device itself, haemolysis, bleeding, and
infection.10
ConclusionWith increasing numbers of aortic valve operations being
undertaken (particularly in the elderly), the burden of significant PVL
requiring repeat intervention will increase. In those patients in whom the risk
of re-operation is high, percutaneous obliteration appears to be a technically
feasible and safe alternative.
Author information: Ali Khan, Cardiology
Registrar, Auckland City Hospital; Peter N Ruygrok, Interventional
Cardiologist, Auckland City Hospital; Paisan Nakpathomkun, Interventional
Fellow, Auckland City Hospital;
Ivor L Gerber, Cardiologist, Auckland City Hospital; Nicholas Kang, Cardiac Surgeon, Auckland City Hospital; Auckland Correspondence: Dr Ali Khan, Green Lane
Cardiovascular Service, Level 3, Auckland City Hospital, Private Bag 92024,
Auckland 1030, New Zealand.
Fax: +64 (0)9 3074950; email: Ali.Khan@waitematadhb.govt.nz References:
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