Cardiovascular Journal of Africa: Vol 27 No 4 (July/August 2016)

CARDIOVASCULAR JOURNAL OF AFRICA • Volume 27, No 4, July/August 2016

240

AFRICA

Short- and long-term outcomes of peripheral artery stents

are available for metal, nitinol and e-PTFE-coated nitinol

stents. Initially, efforts were directed at overcoming the negative

outcomes of metal stents, especially in long lesions.

Owing to

the recent advances in stent technology, biodegradable stents

have been produced to avoid the undesirable outcomes of classic

stents, which lead to mechanical restenosis with stent fracture.

This technology has been extensively evaluated in the

coronary artery system, but not in peripheral arteries. The

outcome of bio-absorbable stents remains unclear.

We therefore

investigated the patency rates of this technology in the peripheral

arterial system.

Outcomes of even classical stents have not been sufficiently

documented. Short hospitalisation times, successful outcomes in

stent patency, higher secondary patency rates, and comparable

outcomes with grafts have increased the popularity of peripheral

stent applications in TASC type A and B lesions. The primary

and secondary patency rates of PTFE-coated stents in veins

above the knee have equal efficacy to PTFE grafts, and are

comparable with that of saphenous veins. Formation of the

neo-intima layer in closed stents prevents the development of

restenosis in the early period, and ensures that stents remain

patent for a longer period.

15,16

The use of stents for suitable lesions, especially in the case of

iliac artery lesions, protects the patient from possible abdominal

surgery and increases the incidence of long-term patency as the

vein diameter is also suitable. In the present study, stenosis was

not observed during the follow-up period after iliac artery stent

implantation.

The PLLA peripheral stent is the first fully bioresorbable stent

to be implanted in humans, with complete degradation taking

12 to 24 months. This resulted in less vessel wall injury during

implantation and therefore less initial thrombus formation and

reduced intimal hyperplasia.

The existing literature on the use of biodegradable peripheral

stents on coronary arteries is limited, and their superiority over

drug-releasing stents has not been proven to date. The existing

data regarding the use of biodegradable peripheral stents in

peripheral arteries is insufficient.

The application of biodegradable peripheral stents has

positive contributions to the collateral system in particular.

The collateral system in the application area does not close, but

rather increases in the long term, and supports development of

the existing systems.

Collateral closure was not observed during

the procedure in our patient group, and we also observed that

these veins stayed open in the patient group examined with DSA.

The major advantages of using biodegradable stents

include practical application, a suitable structure for secondary

interventions, their absorbable and non-depositing nature,

perfect tissue compatibility, and a lower rate of restenosis in

experimental studies. A feature of the biodegradable stent

is that it allows for re-intervention due to its structure (after

implantation of the stent, integration occurs between the stent

structure and vessel wall). Therefore re-intervention can easily

be carried out (balloon and stent or surgery) in TASC type

A lesions when they become TASC type C or D. Another

advantage is that there is no possibility of stent fracture, which

eliminates anti-aggregant use. They are also suitable for use in

patients with a metal allergy.

There are certain disadvantages, including insufficient number

of clinical studies investigating long-term outcomes. Moreover,

the length and diameter of the available stents are not suited for

every clinical scenario.

The absence of a control group was the main limitation of

this study. The ethics committee approved the study protocol,

which was created with the use of a single type of stent to avoid

bias and to provide similar opportunities for all patients. This

pilot study was therefore conducted without a control group.

Conclusion

In this study, primary implantation of a Remedy

biodegradable

stent for moderate-length lesions in lower-extremity arterial

occlusive segments of patients with claudication was associated

with better mid-term results. Our experience shows that the

Remedy

peripheral stents were safe and effective in our cohort

of patients, with acceptable patency rates.

References

Schillinger M, Erich Minar E. Past, present and future of femoro-

popliteal stenting.

J Endovasc Ther

2009;

: I147–I152.

Ansel GM, Lumsden AB. Evolving modalities for femoropopliteal inter-

ventions.

J Endovasc Ther

2009;

: II82–II97.

Onuma Y, Serruys PW. Bioresorbable scaffold: the advent of a new era

in percutaneous coronary and peripheral revascularization?

Circulation

2011;

123

: 779–797.

Waksman R, Pakala R. Biodegradable and bioabsorbable stents.

Curr

Pharm Des

2010;

: 4041–4051.

Biamino G, Schmidt A, Scheinert D. Treatment of SFA lesions with

PLLA biodegradable stents: results of the PERSEUS study.

J Endovasc

Ther

2005;

: 5.

Garg S, Serruys P. Biodegradable stents and non-biodegradable stents.

Minerva Cardioangiol

2009;

: 537–565.

Macaya C, Moreno R. Bioabsorbable drug-eluting stents: the future of

coronary angioplasty? N

at Clin Pract Cardiovasc Med

2008;

: 598–599.

doi: 10.1038/ncpcardio1306.

Wykrzykowska JJ, Onuma Y, Serruys PW. Advances in stent drug deliv-

ery: the future is in bioabsorbable stents.

Expert Opin Drug Deliv

2009;

: 113–126. doi: 10.1517/17425240802668495.

Norgren L, Hiatt WR, Dormandy JA, Nehler MR, Harris KA, Fowkes

FG; TASC II Working Group. TASC II Working Group Inter-Society

Consensus for the Management of Peripheral Arterial Disease (TASC

II).

J Vasc Surg

2007;

: 5–67.

10. Biancari F, Kantonen I, Albäck A, Mätzke S, Luther M, Lepäntalo M.

Limits of infrapopliteal bypass surgery for critical leg ischemia: when

not to reconstruct.

World J Surg

2000;

: 727–733.

11. Scheinert D, Katsanos K, Zeller T, Koppensteiner R, Commeau P,

Bosiers M, et al. ACHILLES Investigators. A prospective randomized

Table 3. Clinical imaging and severity of

stenosis according to symptoms

< 50%

stenosis

50–70%

stenosis

≥

70%

stenosis

Symptomatic patients: DSA (

= 4)

–

Asymptomatic patients: DSA (

= 9)

–

Asymptomatic patients: USG (

= 52)

3**

–

Total

*All were superficial femoral artery (SFA) lesions.

**Two patients had SFA stents; one had a popliteal artery stent.

USG: ultrasonography; DSA: digital subtraction angiography.