Discussion
We report here a successful surgical treatment of a potential
life-threatening complication of PMC.
The treatment of SVMS has been revolutionized since the development of
PMC in 1980s: trans-septal catheterization is one of the most crucial
procedural steps and the Inoue balloon technique is the standard of care
for PMC.(1)
According to the latest ESC/EACTS Guidelines PMC represents the
first-line treatment (class I, level B) for most symptomatic SVMS and
favourable morphology.(1)
However, albeit very high procedural success rates of PMC have been
reported by Bauleti et al.(2), long-term freedom from
reintervention (either repeat PMC and surgery) is only about 38±2%.
In addition, PMC in-hospital mortality rate is up to 0.4% and the most
common complications were embolic stroke and severe mitral
regurgitations, occurring in 0.3% and 3.4%
respectively.(3)
Finally, Iung et al. (4) reported an incidence of
technical failure of 1.2%, due to hemopericardium, embolism, inability
to cross the septum, or inability to position the balloon across the
valve.
The need for surgery was estimated to occur in 4.7% during the first
post-procedural month.
As far as causes of cardiac perforation during PMC are concerned,
several mechanisms have been identified(5) 1) apical
tears by straight-tip balloon catheters driven distally during mitral
valve dilatation, 2) apical perforations by guidewires introduced
through catheters wedged in the apex, 3) tear of the posterior right
atrial wall by dilatation of the track produced by very low septal
punctures, 4) right ventricular perforation by a pacing catheter, and 5)
perforation of the aortic root and adjacent right atrium by sliding up
of the trans-septal set. Of note, cardiac perforation was identified to
be significantly related to the total experience at the Center and to
patient age.
In our case, a type 5 mechanism of perforation occurred, despite the
high-volume experience of the performing Centre.
In conclusion, local policies may allow risky percutaneous procedures to
be performed in high-volume Cardiology Centres without cardiac Surgery
onsite. Although we recommend these procedures to be “centralized” in
third-level Hospitals with prompt availability of on-site Cardiac
Surgery, successful surgical treatment of life-threatening complications
following risky percutaneous procedures in unfavourable logistics can be
achieved by a Heart Team approach providing ad-hoc availability of
dedicated “stand-by” operating theatre.