A
B C
D E
suboptimal DES expansion, which is a predictor
for both periprocedural complications and stent
failure in the long-term due to stent thrombosis
or in-stent restenosis. 1 With the introduction and
implementation of adjunctive techniques, such
as rotational atherectomy, scoring balloon
angioplasty and recently orbital atherectomy
and intravascular lithotripsy, the endovascular
treatment of such severely calcified lesions has
become increasingly feasible, more predictable
and therefore safer.
Techniques for lesion crossing
Methods for facilitating crossing of complex
lesions, include the use of microcatheters,
extension catheters to increase back-up support,
over-the-wire balloons, as well as the use of large
7F or 8F support catheters and of anchor balloon
support techniques. 2
Non-compliant, cutting and scoring balloons
After successful crossing of calcified coronary
lesions with a guide wire, the use non-compliant
balloons at high pressures is necessary to
predilate such lesions. However, lesions with
severe concentric calcification may become
resistant even to non-compliant balloons despite
inflation at high pressures. In addition, the use of
high pressures in such stiff calcified lesions may
cause dissection or even coronary rupture. 3
In cases where non-compliant balloons cannot
properly expand, the use of scoring balloons may
facilitate better lesion preparation. Such balloons
are surrounded by external nitinol spiral scoring
wires and are more flexible and better deliverable
than previously used cutting balloons. Dilatation
using such balloons creates
a ‘scoring’, that is, a calcium fracturing’ effect
into the calcified and fibrotic tissue of the lesion
through a focused transmission force, applied
by the very distal portion of these elements.
Generally, scoring balloons may be successful
for the treatment of moderately to severe
calcified coronary lesions.
Figure 1
Images of an 82-year old
female patient, with history
of 3 vessel CAD and prior
bypass surgery, who was
referred to our department
with non-ST elevation
myocardial infarction.
Coronary angiography
showed a patent left
mammary graft to the left
ascending coronary artery,
a functionally occluded
right coronary artery (not
shown) and multiple tight
lesions in the circumflex
coronary artery (blue
arrows in A). During prior
bypass surgery nine
years ago, a graft could
not be inserted to the
circumflex artery due to
severe calcification. We
therefore proceeded with
rotational atherectomy of
the circumflex artery (B–E),
which was followed by
the implantation of three
DES in the circumflex and
in the left main coronary
artery, with a good final
angiographic result in F.
F
whereas non-fibrocalcific, elastic components are
spared by deflecting away from the burr. Current
guidelines recommend the use of rotational
atherectomy for plaque modification before
adjacent treatment with balloon angioplasty and
DES placement. Although a recent randomised
trial was not able to demonstrate a long-term
benefit for the use of rotational atherectomy in
complex calcified coronary lesions, this technique
is widely accepted as the default strategy for such
lesions prior to DES placement. 4 An example of
a severely calcified lesion in the circumflex artery
of a patient treated with rotational atherectomy
prior to the implantation of three DES is shown
in Figure 1.
Orbital atherectomy
With orbital atherectomy, an eccentrically
mounted diamond-coated crown that orbits
360 degrees within the vessel is used for
circumferential plaque removal. Calcific plaque
tissue can be removed in this way without
causing vessel wall trauma. In contrast to
rotational atherectomy, which is limited by the
size of the catheter tip or burr size, the debulked
area can be increased by increasing the rotational
speed of the eccentrically mounted crown. Like
rotational atherectomy, orbital atherectomy is
also recommended in severely calcified coronary
lesions to provide plaque modification prior to
balloon angioplasty and DES placement. Orbital
atherectomy was approved in 2013 in the US and
has approved in Europe in 2018. This technique
is available for both coronary and peripheral
vessels.
Intracoronary lithotripsy
Intravascular lithotripsy uses pulsatile mechanical
energy in order to disrupt calcific lesions, similar
to extracorporeal lithotripsy used to disrupt
kidney stones. This is facilitated by a balloon
angioplasty catheter, containing a series of
electrohydraulic lithotripsy emitters, which are
used to convert electrical energy to transient
acoustic pressure pulses. The single use balloon
catheter is connected to a generator, which
enables the delivery of prespecified pulse per
treatment. First human studies demonstrated the
safety and high efficacy of the lithotripsy catheter
balloon angioplasty for the treatment of heavily
calcified lesions, exhibiting a low rate of major
adverse events during 30 days of follow-up. 5 In
this regard, high resolution optical coherence
Rotational atherectomy
Rotational atherectomy has been introduced in
the field of interventional cardiology about three
decades ago, primarily aiming at mechanical
debulking of severely fibrocalcific atherosclerotic
plaque. This technique provides ablation of
fibrocalcific plaque components through a
high-speed rotating burr (~140,000–180,000rpm),
7
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