As we known, drug-eluting stents (DES) reduce the risk of restenosis and represent
an important advance in coronary intervention. Newer-generation DES with thin struts
releasing limus-family drugs from durable or biodegradable polymers have further improved
clinical outcomes, as compared with early-generation DES releasing sirolimus or paclitaxel.
The risk of stent thrombosis has become exceedingly low, that is, the improved safety
profile of newer DES comes without compromising their effectiveness. Therefore, DES
should be used in most clinical settings unless pateints have contraindications to
the use of dual antiplatelet therapy.[1] For better stent apposition to improve clinical
outcomes, debulking may be needed in ostial lesions, in diffuse disease, and in calcified
segments before stent implantation. The rotablator is uniquely suited for these indications.[2]
Rotational atherectomy (RA) was developed to differentially remove inelastic and even
harder calcified atherosclerotic plaque without damaging normal arterial wall by the
rotating burr.[3] Actually, rotablator is the only surviving debulking device nowadays
for lesion preparation before stent implantation, i.e., to remove the most calcified
and unyielding elements of the plaque, leaving a soft tissue rim to dilate and stent.[2]
In this issue of the Journal of Geriatric Cardiology, Dr. Chen and Hsieh recommended
that a strategy combining the RA technique and DES implantation is a safe and effective
treatment option for patients with complex lesions.[4] It should be considered as
an essential technique in certain lesions, especially the calcified lesions visible
by fluoroscopy, circumferential calcific lesions, or lesions uncrossable with the
intravascular ultrasound catheter. Given that the population is getting older, and
that the proportion of patients with coronary calcified lesions will increase in proportion
with the octogenarians, RA should be offered in all the catheterizarion laboratories.
Traditionally, RA was used to ablate previously undilatable lesions and heavily calcified
lesions. With refinement of technique, more recently, the indications of RA have been
extended beyond those traditionally ones and rotablator has been confirmed as a predictable
device in the treatment of more complex lesions in experienced centers.[5] In this
issue, Chiang et al.[6] reported their exprerience of using RA to treat heavily calcified
left-main coronary diseases (LMCA), which was previously considered a formidable challenge
for percutaneous interventions. Their results clearly demonstrated that in experienced
hands, plaque modification with RA before stenting of heavily-calcified LMCA could
be safely accomplished in those elderly patients with high-surgical-risk, with a minimal
complication rate and favorable long-term outcomes.
Coronary stent implantation in a severely calcified vessel may result in stent underexpansion,
leading to life-threatening complication, such as stent thrombosis.[7] In this issue,
Ku, et al.[8] reported a patient suffered from late stent thrombosis due to under-deployment
of a paclitaxel-eluting stent in a lesion with circumferential calcification. This
rare but serious complication was sucessfully treated by RA, represented a new indication
of rotablation. Intravascular ultrasound revealed that rotablator could successfully
ablate both the underexpanded metallic struts of the stent and the calcified ring.
The ablated segment was scaffolded with a new paclitaxel-eluting stent, which was
well opposed.
However, despite such a wide range of applications of RA, why is it that the widespread
use of RA has been hampered? One of the reasons is that RA is a demanding technique
requires training and experience to perform. Moreover, RA is associated with complications
such as coronary vasospasm, slow flow, etc. Furthermore, a concern for device specific
complictions exists.[9],[10] One of the rare but devastating device specific complications
during rotablation is entrapment of the burr within calcified lesion, which is really
a nightmare of interventional cardiologist. In this issue, Lin et al.[11] reported
a series of 5 cases of this particular complication. They also discussed the possible
mechanisms, proposed methods to rescue the complication percutaneously, and the tips
and tricks to avoid such a serious complication.
In conclusion, RA can improve acute results in difficult lesion subsets and is now
considered as a niche device in coronary intervention. However, many operators are
reluctant to use RA extensively and still reserve it for the most difficult lessions
which cannot be treated by any other methods. This extreme selection bias may prevent
operators from getting the experiences to use the device effectively and have a negative
impact on the procedure outcomes. It is believed that proctorships and training courses
should improve results and acceptance of RA in the future. If increasing numbers of
operators are able to obtain predictable results from improved technique, if more
favorable data are obtained from randomized trials, if the equipment becomes more
user-friendly, and if its cost becomes more competivie, then RA will be established
as a major tool in percutaneous treatment of coronary heart disease.