4.1 Surgical management
Open heart surgery is a gold standard treatment provided for significant
and complex PVLs; it either aims to repair or replace the valve27. The surgical strategy is decided based on factors
such as patient status, the aetiology, the condition of the native
annulus, the size and location of the leak and whether the area is
accessible27. The use of open surgery is reduced
primarily due to the high morbidity and mortality
rates28. The rate of recurrence of paravalvular leaks
is also common as the underlying pathology is not really treated.
Open-heart surgery is, therefore, performed in cases where: the
execution of percutaneous treatment is contraindicated (e.g. if the
patient presents with active endocarditis), where the prosthetic valve
is dysfunctional 28, or in those who have severe PVLs
(where performing an open-heart surgery has shown improved survival and
reduced symptoms in patients) 27.
Transcatheter aortic valve closure
The use of percutaneous catheter-based methods and other minimally
invasive procedures have developed a great deal of curiosity and
interest with regards to treating PVL and resultant regurgitation as not
only do they treat the PVL but also reduce risk of further re-operation.
To perform the percutaneous method, you need special occlusive devices
and access to the site. The access to the site varies according to what
type of PVL is present; mitral or aortic PVL. Aortic PVL is accessed
through the femoral artery with a retrograde approach. Mitral PVL is
accessed through the femoral vein and a transseptal
puncture28. Whilst performing these procedures, it is
important that the patient is administered general anaesthesia for their
comfort and because there may be long-lasting equipment
dwell27. PVL closures can be performed using three
approaches (transseptal, retrograde transaortic or left ventricle
transapical approaches) and the approach taken is decided based on the
location of leak, the valve involved, presence of any hinderance or
calcification. Aortic paravalvular leaks are treated using the
retrograde transaortic approach.
A hydrophilic guidewire, supported by a catheter, is initially directed
towards the PVL and either echocardiography or fluoroscopy is used to
confirm paravalvular position. The catheter is then inserted into the
left ventricle through the defect. Whilst taking extra precautions, the
hydrophilic wire is subsequently replaced with an extra support wire;
the precautions are necessary to prevent cardiac perforation risk. A
delivery sheath for the device is introduced into the left ventricle and
then pulled into the defect. The correct placement of the device is
confirmed by using TOE27. An overview of a protocol
can be seen pictorially in Figure 3 .
Despite the retrograde transaortic approach being the most ideal for an
aortic PVL, in some cases the transapical approach may be used. The
transapical approach may be necessary when a mitral or aortic mechanical
prosthesis is present or when the retrograde transaortic approach is not
successful. The antegrade transseptal approach requires an exteriorized
arteriovenous (AV) for support and control of the device and sheath
during delivery. When the crossing wire is inserted into the descending
aorta, snared, and then exteriorized through the femoral arterial
sheath, the AV rail is created. It’s important to avoid putting too much
pressure on the left ventricle loop, which can entrap the anterior
mitral leaflet and produce severe mitral
regurgitation27.
Outcomes of PVL management
Surgical treatment of mild and moderate PVLs with no adverse effects is
successful in almost 80-90% of patients29.
Complications due to treatment using the transcatheter method is rare.
Studies that investigated the emergence of adverse effects in 115
patients noticed that in a 30-day period post treatment, 1.7% had an
unexplained or sudden death, 2.6% had a stroke, 0.9% required an
emergency surgery and 5.2% required treatment for periprocedural
bleeding30 31. Two studies had also
noticed that 2.5% of patients had experienced device embolism and death
was seen in approximately 0.5% of patients 3031.
The transcatheter method may not be successful in some patients. This
can be due to impingement of the prosthetic leaflet and the inability to
guide the catheter or cross the defects of the wire. Although it is more
common for impingement to occur in patients with mechanical valves, it
can occur with any prosthesis. Impingement can be prevented with the use
of smaller devices but can still be challenging with the nature of the
shape of occluders and the location, with regards to the surgical
annular ring. Clinical success and the symptoms experienced by patients
is dependent upon the degree of regurgitation; it is also seen that
those who have heart failure suffer a greater deal of symptoms compared
to those with haemolysis 32.
In a study looked at the risk of death and developing heart failure with
rehospitalization in 1661 patients after 1-year post-TAVR. A 9.3% of
the patients had died within the year whilst approximately 15% of the
patients had hospitalized with heart failure. Those with the least
moderate form of PVL also had the highest mortality rate. It was also
seen that the degree of PVL had decreased by one class/group in almost
80% of patients33. Another study evaluated the
outcomes seen after 3 years and saw that there was a survival rate of
64%, cardiac-associated death rate of 9.5%, non-cardiac associated
death rate of approximately 10%. 72% of those who survived were
symptom free and did not require any other surgery32.