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Optimization of stent deployment by intravascular ultrasound.

Yoon HJ, Hur SH - Korean J. Intern. Med. (2012)

Bottom Line: Since the introduction of the drug-eluting stent (DES), concerns about restenosis have decreased.However, high-risk lesion subsets are being routinely treated with DESs, and the incidence of suboptimal results after stent deployment, such as stent underexpansion, incomplete stent apposition, edge dissection, geographic miss, and the risk of stent thrombosis, have correspondingly increased.Thus, optimization of stent deployment under IVUS guidance may be clinically important.

View Article: PubMed Central - PubMed

Affiliation: Department of Internal Medicine, Keimyung University Dongsan Medical Center, Daegu, Korea.

ABSTRACT
Intravascular ultrasound (IVUS) is a useful diagnostic method that provides valuable information in addition to angiography regarding the coronary vessel lumen, dimensions, plaque burden, and characteristics. The major use of IVUS in coronary intervention is to guide interventional strategies and assess optimal stent deployment. Since the introduction of the drug-eluting stent (DES), concerns about restenosis have decreased. However, high-risk lesion subsets are being routinely treated with DESs, and the incidence of suboptimal results after stent deployment, such as stent underexpansion, incomplete stent apposition, edge dissection, geographic miss, and the risk of stent thrombosis, have correspondingly increased. Thus, optimization of stent deployment under IVUS guidance may be clinically important. In this review, we focus on the potential role of IVUS in stent optimization during percutaneous coronary intervention and its clinical benefits.

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Stent-related complications after stent deployment.
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Related In: Results  -  Collection

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Figure 2: Stent-related complications after stent deployment.

Mentions: IVUS has been used to detect suboptimal results after apparently angiographically successful stent deployment in both the DES and bare metal stent (BMS) eras (Fig. 2). IVUS predictors that are associated with increased adverse outcomes include smaller MSA, stent underexpansion, stent edge dissection, incomplete stent apposition, and incomplete lesion coverage [19-26]. In the BMS era, a major problem after stent implantation was stent restenosis, and the main mechanism of this phenomenon was a smaller MSA or stent underexpansion [21,26-30]. Several studies in the BMS era showed a beneficial effect of IVUS guidance on post-procedural angiographic results and stent restenosis during long-term follow-up, resulting from a larger MSA with a higher post-dilation balloon pressure [7,19,27,31]. Stent underexpansion, identified by IVUS, can be treated with appropriate post-balloon dilation. IVUS allows more aggressive intervention using a larger diameter balloon with confidence in terms of safety; thus, BMS implantation under IVUS guidance can provide a bigger MSA and more favorable clinical outcomes compared with angiography-guided PCI. DESs have led to a marked reduction in the rate of stent restenosis and the need for repeated revascularization compared with BMSs [32,33]. Because of their efficacy, high-risk lesions and clinical conditions, including bifurcation lesions, long lesions, calcified lesions, left main disease, diabetes, and multivessel disease, are now being treated routinely with DESs [34,35]. Thus, the risk of stent underexpansion, incomplete stent apposition, and incomplete lesion coverage increases and these suboptimal stent deployment conditions have been reported to be potent IVUS predictors of stent restenosis and stent thrombosis [13,17,24], suggesting that stent implantation under IVUS guidance still has a pivotal role even in the DES era. An important aspect of IVUS is determining appropriate reference segments that provide the landing zone for stent deployment. IVUS examination typically reveals a considerable amount of plaque, even in segments of the vessel that appear "normal" on the angiogram, known as "reference vessel" disease. Quantitative IVUS studies have demonstrated that the segment chosen as the "normal" reference site for the calculation of angiographic percent stenosis has an average of 30-50% of its cross-sectional area occupied by plaque [36]. By IVUS, the definition of reference segment is a cross-sectional image adjacent to the lesion that has < 40% plaque burden [37]. A previous study reported the association between clinical outcomes and longitudinal positioning of the stent in 162 consecutive patients with 180 lesions treated with sirolimus-eluting stent (SES) implantation [38]. In that study, stepwise IVUS criteria primarily targeting plaque burden < 50% were shown to be feasible and improved the rates of stent restenosis and target lesion revascularization (TLR) at 8 months follow-up.


Optimization of stent deployment by intravascular ultrasound.

Yoon HJ, Hur SH - Korean J. Intern. Med. (2012)

Stent-related complications after stent deployment.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC3295985&req=5

Figure 2: Stent-related complications after stent deployment.
Mentions: IVUS has been used to detect suboptimal results after apparently angiographically successful stent deployment in both the DES and bare metal stent (BMS) eras (Fig. 2). IVUS predictors that are associated with increased adverse outcomes include smaller MSA, stent underexpansion, stent edge dissection, incomplete stent apposition, and incomplete lesion coverage [19-26]. In the BMS era, a major problem after stent implantation was stent restenosis, and the main mechanism of this phenomenon was a smaller MSA or stent underexpansion [21,26-30]. Several studies in the BMS era showed a beneficial effect of IVUS guidance on post-procedural angiographic results and stent restenosis during long-term follow-up, resulting from a larger MSA with a higher post-dilation balloon pressure [7,19,27,31]. Stent underexpansion, identified by IVUS, can be treated with appropriate post-balloon dilation. IVUS allows more aggressive intervention using a larger diameter balloon with confidence in terms of safety; thus, BMS implantation under IVUS guidance can provide a bigger MSA and more favorable clinical outcomes compared with angiography-guided PCI. DESs have led to a marked reduction in the rate of stent restenosis and the need for repeated revascularization compared with BMSs [32,33]. Because of their efficacy, high-risk lesions and clinical conditions, including bifurcation lesions, long lesions, calcified lesions, left main disease, diabetes, and multivessel disease, are now being treated routinely with DESs [34,35]. Thus, the risk of stent underexpansion, incomplete stent apposition, and incomplete lesion coverage increases and these suboptimal stent deployment conditions have been reported to be potent IVUS predictors of stent restenosis and stent thrombosis [13,17,24], suggesting that stent implantation under IVUS guidance still has a pivotal role even in the DES era. An important aspect of IVUS is determining appropriate reference segments that provide the landing zone for stent deployment. IVUS examination typically reveals a considerable amount of plaque, even in segments of the vessel that appear "normal" on the angiogram, known as "reference vessel" disease. Quantitative IVUS studies have demonstrated that the segment chosen as the "normal" reference site for the calculation of angiographic percent stenosis has an average of 30-50% of its cross-sectional area occupied by plaque [36]. By IVUS, the definition of reference segment is a cross-sectional image adjacent to the lesion that has < 40% plaque burden [37]. A previous study reported the association between clinical outcomes and longitudinal positioning of the stent in 162 consecutive patients with 180 lesions treated with sirolimus-eluting stent (SES) implantation [38]. In that study, stepwise IVUS criteria primarily targeting plaque burden < 50% were shown to be feasible and improved the rates of stent restenosis and target lesion revascularization (TLR) at 8 months follow-up.

Bottom Line: Since the introduction of the drug-eluting stent (DES), concerns about restenosis have decreased.However, high-risk lesion subsets are being routinely treated with DESs, and the incidence of suboptimal results after stent deployment, such as stent underexpansion, incomplete stent apposition, edge dissection, geographic miss, and the risk of stent thrombosis, have correspondingly increased.Thus, optimization of stent deployment under IVUS guidance may be clinically important.

View Article: PubMed Central - PubMed

Affiliation: Department of Internal Medicine, Keimyung University Dongsan Medical Center, Daegu, Korea.

ABSTRACT
Intravascular ultrasound (IVUS) is a useful diagnostic method that provides valuable information in addition to angiography regarding the coronary vessel lumen, dimensions, plaque burden, and characteristics. The major use of IVUS in coronary intervention is to guide interventional strategies and assess optimal stent deployment. Since the introduction of the drug-eluting stent (DES), concerns about restenosis have decreased. However, high-risk lesion subsets are being routinely treated with DESs, and the incidence of suboptimal results after stent deployment, such as stent underexpansion, incomplete stent apposition, edge dissection, geographic miss, and the risk of stent thrombosis, have correspondingly increased. Thus, optimization of stent deployment under IVUS guidance may be clinically important. In this review, we focus on the potential role of IVUS in stent optimization during percutaneous coronary intervention and its clinical benefits.

Show MeSH
Related in: MedlinePlus