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Longitudinal stent deformation (LSD) is an infrequent complication of percutaneous coronary intervention. While the occurrence of gross LSD is a rare phenomenon, minor changes in length are common and have been recognized as accepted behavior of stents during implantation. Due to the proximity of the guide catheter, ostial or ostio-proximal lesions are prone to stent deformation either by the guide or other devices during navigation. Moreover, to satisfy the fractal geometry of coronary bifurcation, the proximal optimization technique is commonly performed during different bifurcation procedures, which can subject the stent to extreme overexpansion resulting in structural deformation. We describe two cases of longitudinal stent elongation during ostial deployment and try to analyze the factors behind this rare, yet complicated behavior of the latest-generation drug-eluting stent.

Abstract Background The diameter of the ostial and proximal left main coronary artery can be greater than 5.0 mm. However, the diameters of the mostly available coronary drug-eluting stents (DESs) are ≤ 4.0 mm. Whether high-pressure dilatation can increase the diameter of stents from 4.0 to 5.0 mm and whether post-dilatation leads to longitudinal stent deformation (LSD) of 4.0-mm-diameter stents have rarely been studied. Therefore, this study aims to evaluate LSD and stent malapposition of six types of commercially available 4.0-mm-diameter stents in China in a 5.0-mm-diameter artificial blood vessel model by optical coherence tomography (OCT) in vitro. Methods The left main coronary artery was simulated by a truncated cone-shaped silicone tube. The internal diameters were 4.0 mm at one end of the silicone tube and 5.0 mm at the other end. Six different types of coronary stents widely used in China were selected for this study. Each stent was respectively implanted into the simulated blood vessel and dilated to a diameter of 4.2 mm according to the stent-balloon pressure compliance table. The stents were subjected to post-dilatation with a 5.0 × 15-mm noncompliant balloon. The LSD ratio of the longitudinal axis of each stent and stent malapposition were measured through OCT, and any fractures of the stents were determined. Results None of the six types of stents fractured following post-dilatation. The longitudinal axes of the BuMA and Excrossal stents were slightly shortened, while the other stents were elongated after high-pressure post-dilatation. All stents expanded to a diameter of 5.0 mm without incomplete stent apposition, except for the Nano Plus stent, which remained malapposed after high-pressure post-dilatation. Conclusion All 4.0-mm-diameter stents can be expanded to a diameter of 5.0 mm by noncompliant balloon post-dilatation without stent strut fracture. Most stents were found to be well apposed after high-pressure post-dilatation. However, LSD was observed after post-balloon dilatation. Stent malapposition might be positively correlated with the percentage change in stent length.

It has been rarely reported that a stuck optical coherence tomography (OCT) catheter can lead to longitudinal stent deformation (LSD). This complication can result in incomplete stent apposition and dissection after stent implantation. In this study, we present a case where a bailout stent was implanted in the distal segment of the left anterior descending artery (LAD) after longitudinal stent deformation caused by a stuck OCT catheter. This approach was taken to prevent acute stent thrombosis, subacute stent thrombosis, in-stent restenosis (ISR), and death. The patients were followed up for one year, and no adverse events were observed. [ABSTRACT FROM AUTHOR]

Background: The diameter of the ostial and proximal left main coronary artery can be greater than 5.0 mm. However, the diameters of the mostly available coronary drug-eluting stents (DESs) are ≤ 4.0 mm. Whether high-pressure dilatation can increase the diameter of stents from 4.0 to 5.0 mm and whether post-dilatation leads to longitudinal stent deformation (LSD) of 4.0-mm-diameter stents have rarely been studied. Therefore, this study aims to evaluate LSD and stent malapposition of six types of commercially available 4.0-mm-diameter stents in China in a 5.0-mm-diameter artificial blood vessel model by optical coherence tomography (OCT) in vitro. Methods: The left main coronary artery was simulated by a truncated cone-shaped silicone tube. The internal diameters were 4.0 mm at one end of the silicone tube and 5.0 mm at the other end. Six different types of coronary stents widely used in China were selected for this study. Each stent was respectively implanted into the simulated blood vessel and dilated to a diameter of 4.2 mm according to the stent-balloon pressure compliance table. The stents were subjected to post-dilatation with a 5.0 × 15-mm noncompliant balloon. The LSD ratio of the longitudinal axis of each stent and stent malapposition were measured through OCT, and any fractures of the stents were determined. Results: None of the six types of stents fractured following post-dilatation. The longitudinal axes of the BuMA and Excrossal stents were slightly shortened, while the other stents were elongated after high-pressure post-dilatation. All stents expanded to a diameter of 5.0 mm without incomplete stent apposition, except for the Nano Plus stent, which remained malapposed after high-pressure post-dilatation. Conclusion: All 4.0-mm-diameter stents can be expanded to a diameter of 5.0 mm by noncompliant balloon post-dilatation without stent strut fracture. Most stents were found to be well apposed after high-pressure post-dilatation. However, LSD was observed after post-balloon dilatation. Stent malapposition might be positively correlated with the percentage change in stent length. [ABSTRACT FROM AUTHOR]

Abstract Even skilled CHIP operators can run into multiple complications. Some are unexpected and not related to the operator, and others are fully preventable by careful procedural choices. If those occur, the knowledge of devices and cognitive skills become lifesaving elements and sudden issues need to be dealt with calmly and efficiently.

Abstract Background Longitudinal stent deformation (LSD) is an infrequent complication of percutaneous coronary intervention (PCI), and it may lead to catastrophic clinical outcomes. However, reports of cardiac adverse events associated with LSD are rare. Case presentation A 55-year-old man with chest pain was treated for a severe left anterior descending branch (LAD)-diagonal 1 (D1) bifurcation lesion by PCI with two stents in the proximal LAD. LSD occurred during the withdrawal of the trapped D1 wire. High-pressure balloon dilatation was performed in the deformed stent, and the end-angiographic appearance was acceptable, but no additional corrective measures were implemented. Ten months later, the patient represented with acute coronary syndrome. Severe in-stent restenosis (ISR) had suboccluded the proximal LAD, and optical coherence tomography (OCT) visualized multilayered stent struts protruding into the lumen at the compressed segment of the stent. Following complete apposition with balloon dilation, a drug-coated balloon (DCB) was used to avoid an additional permanent metallic layer. He remained angina free, and the angiographic result demonstrated no residual stenosis at the six-month follow-up. To our knowledge, this case demonstrates the first report of ISR triggered by LSD in patients treated with DCBs under the guidance of OCT. Conclusions The current report underscores the importance of awareness of LSD, and OCT seems to be the preferred modality to confirm complete apposition. If left without performing additional corrective measures, LSD may be associated with a risk of ISR. Complete apposition with balloon dilation followed by a DCB is a feasible treatment option.

Changing any element of a stent structure can alter certain aspects of how a stent can function. Although thinner struts and lower metal-to-artery ratio enhance the stent delivery, the disadvantage is lower radial force. Decreasing the number of fixed connectors between cells and changing the geometric and spatial distribution of these connectors improve flexibility and conformability, but at the cost of the longitudinal strength of the stent structure. Never as a standard parameter has the longitudinal strength or compressibility of coronary stents been published nor previously considered important. We discuss a case detailing that, particularly in the contemporary practice of interventional cardiology, stent longitudinal strength is a very significant and important feature of these devices.

It has been rarely reported that a stuck optical coherence tomography (OCT) catheter can lead to longitudinal stent deformation (LSD). This complication can result in incomplete stent apposition and dissection after stent implantation. In this study, we present a case where a bailout stent was implanted in the distal segment of the left anterior descending artery (LAD) after longitudinal stent deformation caused by a stuck OCT catheter. This approach was taken to prevent acute stent thrombosis, subacute stent thrombosis, in-stent restenosis (ISR), and death. The patients were followed up for one year, and no adverse events were observed., Competing Interests: The authors declare no conflict of interest., (Copyright: © 2024 The Author(s). Published by IMR Press.)

Even skilled CHIP operators can run into multiple complications. Some are unexpected and not related to the operator, and others are fully preventable by careful procedural choices. If those occur, the knowledge of devices and cognitive skills become lifesaving elements and sudden issues need to be dealt with calmly and efficiently. [ABSTRACT FROM AUTHOR]

Background: Longitudinal stent deformation (LSD) is an infrequent complication of percutaneous coronary intervention (PCI), and it may lead to catastrophic clinical outcomes. However, reports of cardiac adverse events associated with LSD are rare.Case Presentation: A 55-year-old man with chest pain was treated for a severe left anterior descending branch (LAD)-diagonal 1 (D1) bifurcation lesion by PCI with two stents in the proximal LAD. LSD occurred during the withdrawal of the trapped D1 wire. High-pressure balloon dilatation was performed in the deformed stent, and the end-angiographic appearance was acceptable, but no additional corrective measures were implemented. Ten months later, the patient represented with acute coronary syndrome. Severe in-stent restenosis (ISR) had suboccluded the proximal LAD, and optical coherence tomography (OCT) visualized multilayered stent struts protruding into the lumen at the compressed segment of the stent. Following complete apposition with balloon dilation, a drug-coated balloon (DCB) was used to avoid an additional permanent metallic layer. He remained angina free, and the angiographic result demonstrated no residual stenosis at the six-month follow-up. To our knowledge, this case demonstrates the first report of ISR triggered by LSD in patients treated with DCBs under the guidance of OCT.Conclusions: The current report underscores the importance of awareness of LSD, and OCT seems to be the preferred modality to confirm complete apposition. If left without performing additional corrective measures, LSD may be associated with a risk of ISR. Complete apposition with balloon dilation followed by a DCB is a feasible treatment option. [ABSTRACT FROM AUTHOR]

Recently, longitudinal stent deformation (LSD) has been increasingly reported with 2nd generation drug eluting stents (DES). Though, the reported cases are with all type of stents, it is common with Promus Element stent. It is either caused by impact of guide catheter’s tip at proximal or osteal stent site, or following secondary passage of catheters like balloon catheters, IVUS or OCT catheters, guideliner, etc. We hereby report 3 cases of LSD who had this technical complication because of three different reasons. All of them were successfully managed, and had favorable short term outcomes.

Introduction: Drug-eluting stents (DES) are still the standard of care in percutaneous coronary intervention (PCI) since the fall of bioresorbable scaffolds with respect to safety. The unbeatable advantage of a metallic stent when compared with a scaffold is a stronger mechanical property and more sustainable vascular support. Recent development of contemporary metallic stent has focused on the reduction of strut thickness. However, there will always be a trade-off between improvement in deliverability, flexibility, and radial strength. Areas covered: This review aims to discuss the designs of metallic stent platform and mechanical properties as well as mechanical performance of contemporary DES from bench studies and clinical trials. Expert opinion: Mechanical properties of stents affect short- and long-term clinical outcomes. Ultrathin-strut DES have become popular and clinical trials have shown impressive results. Thinner struts may improve device flexibility and deliverability but the radial strength and longitudinal integrity might have been compromised as well. Ultrathin-strut cobalt chromium or platinum chromium DES will become standard of care in PCI practice in the near future. Information on the stent design, stent material and mechanical properties of the stent are essential for a rational selection of the appropriate stent in selected lesions and patients. [ABSTRACT FROM AUTHOR]

Changing any element of a stent structure can alter certain aspects of how a stent can function. Although thinner struts and lower metal-to-artery ratio enhance the stent delivery, the disadvantage is lower radial force. Decreasing the number of fixed connectors between cells and changing the geometric and spatial distribution of these connectors improve flexibility and conformability, but at the cost of the longitudinal strength of the stent structure. Never as a standard parameter has the longitudinal strength or compressibility of coronary stents been published nor previously considered important. We discuss a case detailing that, particularly in the contemporary practice of interventional cardiology, stent longitudinal strength is a very significant and important feature of these devices. [ABSTRACT FROM AUTHOR]

Objectives To evaluate whether balloon inflation for post-dilatation causes longitudinal stent deformation (LSD). Methods and results Two stents, sized 2.5 mm × 28 mm and 3.5 mm × 28 mm (Nobori ® , biodegradable polymer biolimus-eluting stent; Ultimaster ® , biodegradable polymer sirolimus-eluting stent; Terumo Co., Tokyo, Japan), were deployed at nominal pressure in straight and tapered silicon vessel models. Then, post-dilatation was performed in two ways: dilatation from the distal (D-P group) or proximal (P-D group) side of the stent. Microscopic findings showed that the stents were elongated during every step of the procedure regardless of the post-dilatation method and type of vessel model. The D-P group showed linear elongation during each step of post-dilatation (straight model: 28.7 ± 0.3 mm vs. 29.9 ± 0.3 mm, p = 0.002; tapered model: 28.0 ± 0.1 mm vs. 29.9 ± 0.1 mm, p < 0.001). In contrast, in the P-D group, the most significant change was observed in the first step of post-dilatation and only slight changes were observed thereafter (straight model: 28.6 ± 0.1 mm vs. 29.5 ± 0.1 mm, p < 0.001; tapered model: 28.2 ± 0.1 mm vs. 29.5 ± 0.1 mm, p < 0.001). Optical frequency domain imaging analysis showed that the frequency of stent strut malapposition was positively correlated with the percentage change in stent length ( r = 0.74, p < 0.0001). Conclusion LSD was observed during every step of post-dilatation in both the straight and tapered vessel models. However, some differences were observed between the D-P and P-D groups. Minimizing stent strut malapposition may reduce the risk of LSD. [ABSTRACT FROM AUTHOR]

Recently, longitudinal stent deformation (LSD) has been reported increasingly. Even though the reported cases included almost all stent designs, most cases were seen in the Element™ stent design (Boston Scientific, Natick, MA, USA). It is considered that stent design, lesion and procedural characteristics play a role in the etiology of LSD. Yet, the effect of LSD on long-term clinical outcomes has not been studied well. Element stents implanted between January 2013 and April 2015 in our hospital were examined retrospectively. Patients were grouped into two according to the presence of LSD, and their clinical, lesion and procedural characteristics were studied. Twenty-four LSD's were detected in 1812 Element stents deployed in 1314 patients (1.83 % of PCI cases and 1.32 % of all Element stents). LMCA lesions (16.7 % vs 1.6 %, p < 0.001), complex lesions (75 % vs 35.1 %, p < 0.001), bifurcation lesions (37.5 % vs 18.3 %, p = 0.017), ostial lesions (33.3 % vs 12.8 %, p = 0.003), using of extra-support guiding catheter (54.2 % vs 22.3 %, p < 0.001) and extra-support guidewire (37.5 % vs 16.2 %, p = 0.005) were found to be more frequent in cases with LSD than in cases without it. In addition, the number of stents, stent inflation pressure and the use of post-dilatation were significantly different between the two groups. Two patients had an adverse event during the follow-up period. LSD is a rarely encountered complication, and is more common in complex lesions such as ostial, bifurcation and LMCA lesions. The use of extra-support guiding catheter, extra-support guidewires and low stent inflation pressure increases the occurrence of LSD. Nevertheless, with increased awareness of LSD and proper treatment, unwanted long-term outcomes can be successfully prevented. [ABSTRACT FROM AUTHOR]

Résumé La compression longitudinale de stent se définit comme un raccourcissement de longueur de l’endoprothèse après son implantation. C’est une complication rare dont les conséquences peuvent être sévères ; elle a été décrite avec plusieurs plateformes de stents. Nous rapportons un cas de compression longitudinale de stent survenue lors du traitement d’une bifurcation coronaire avec une endoprothèse Promus Element ® et proposons une brève mise au point décrivant les lésions à haut risque, les principaux mécanismes responsables et les traitements de cette complication. Longitudinal stent deformation is defined as a compression of stent length after its implantation. It's a rare complication but dangerous seen with several stents. We reported a case of longitudinal stent deformation during bifurcation lesion treatment with a Promus Element ® and we perform a short review of this complication. [ABSTRACT FROM AUTHOR]

Background Longitudinal stent deformation (LSD) in drug-eluting stents (DES) has been described as a disruption of stent structure. This study aimed to compare first- versus second-generation DES with respect to their actual stent length post deployment. Methods A total of 617 DES for de novo coronary lesions in 552 patients were analyzed. Intravascular ultrasound (IVUS) was utilized to compare the degree and rate of LSD among six different DES types. IVUS-measured stent length was compared to the labeled length for calculation of absolute difference in stent length and relative absolute difference (absolute difference divided by the labeled length). Results The baseline characteristics were comparable between groups, except for higher calcification in the sirolimus-eluting stent (SES) group (p=0.037). The absolute and relative difference in length showed the lowest degree in the SES group and the highest degree in the Endeavor zotarolimus-eluting stent group (p=0.085 and 0.078, respectively). The percentage of more than 5% relative absolute difference was the lowest in the SES group compared to the other groups (p=0.018). However, the percentage of significant (>15%) relative absolute difference was similar among groups (p=0.99). In multivariate linear regression analysis, labeled stent length and stent diameter, but not stent type, were identified as independent correlates to the absolute and relative difference in the actual stent length post-deployment. Conclusion This IVUS analysis confirms that among second-generation DES, there is overall similar frequency and severity of LSD when deploying in common coronary lesions. [ABSTRACT FROM AUTHOR]

Abstract: In percutaneous coronary intervention (PCI), stent malapposition is a common complication often leading to stent thrombosis (ST). More recently, it has also been associated with longitudinal stent deformation (LSD) normally occurring through contact of a post balloon catheter tip and the protruding malapposed stent struts. The aim of this study was to assess the longitudinal integrity of first and second generation drug eluting stents in a patient specific coronary artery segment and to compare the range of variation of applied loads with those reported elsewhere. We successfully validated computational models of three drug-eluting stent designs when assessed for longitudinal deformation. We then reconstructed a patient specific stenosed right coronary artery segment by fusing angiographic and intravascular ultrasound (IVUS) images from a real case. Within this model the mechanical behaviour of the same stents along with a modified device was compared. Specifically, after the deployment of each device, a compressive point load of 0.3N was applied on the most malapposed strut proximally to the models. Results indicate that predicted stent longitudinal strength (i) is significantly different between the stent platforms in a manner consistent with physical testing in a laboratory environment, (ii) shows a smaller range of variation for simulations of in vivo performance relative to models of in vitro experiments, and (iii) the modified stent design demonstrated considerably higher longitudinal integrity. Interestingly, stent longitudinal stability may differ drastically after a localised in vivo force compared to a distributed in vitro force. [Copyright &y& Elsevier]

A distortion of implanted coronary stent along its longitudinal axis during coronary intervention is known as longitudinal stent deformation (LSD). LSD is frequently seen with newer drug eluting stents (DES), specifically with PROMUS Element stent. It is usually caused by impact of guide catheter tip, or following passage of catheters like balloon catheter, IVUS catheter, guideliner, etc. We hereby report a case of LSD during coronary bifurcation lesion intervention, using two-stents technique. Patient had acute stent thrombosis as a complication of LSD, which was successfully managed. [ABSTRACT FROM AUTHOR]

Longitudinal stent deformation is defined as shortening or elongation of the stent along its longitudinal axis after deployment. It is under-recognized on angiography, and imaging- based studies have reported an incidence of up to 1%. The etiology includes damage by the guiding catheter or secondary devices such as postdilation balloons, imaging catheters, additional stents, or wire entanglement. Deformation can occur with all stent platforms. In the present case, forceful removal of the trapped guidewire led to the guide being sucked into the LAD and deforming the stent.

The article focuses on the use of coronary stents in clinical practice and discusses the risk factors associated with the occurrence of longitudinal stent deformation (LSD) during the surgical procedure. It informs that LSD can result in shortening or concertina of the stent within blood vessels and due to several complications associated with traditional stents now alloys of cobalt or platinum is used to maintain strength and radio-opacity.

Longitudinal stent deformation is a recognized complication of coronary angioplasty; however, it is difficult to detect angiographically. This case illustrates the value of OCT to identify and correctly diagnose longitudinal stent deformation.

Percutaneous coronary intervention relieves symptoms in patients with chronic ischemic heart disease resistant to optimal medical therapy and alters the natural history of acute coronary syndromes. However, adverse procedural outcomes may occur during the intervention. Knowledge of possible complications and their timely management are essential for the practicing cardiologist and can be life-saving for the patient. In this review, the authors summarize potential complications of percutaneous coronary intervention focusing on their practical management., (Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objectives: To compare susceptibility of five different stent platforms with longitudinal stent deformation (LSD) using a clinically relevant bench testing model simulating both short and long malapposed lengths., Background: Recent data suggest that design modifications to the Promus Element stent which led to the Promus Premier stent has reduced susceptibility to LSD. However, susceptibility to LSD at long malapposed lengths has not been tested. Furthermore, the mechanisms behind susceptibility to LSD are as yet unclear., Methods: The Omega, Integrity, Multilink 8, Biomatrixand Promus Premier stent platforms were tested. The Omega, Integrity and Multilink 8 platforms were used in place of their drug-eluting equivalents. 3.5 mm stents were deployed in a stepped tube with the distal portion fixed and the proximal test section exposed. The force required to compress stents by a fixed distance at different exposed lengths was compared. Symmetrical and point loading were used., Results: The Promus Premier was longitudinally as strong as Multilink and Integrity at a short exposed length (4 mm) but weaker, in between Omega and the other platforms, at longer exposed lengths (12 mm). As previously noted, the Omega (Promus Element) platform was significantly weaker than the other stents and Biomatrix was the strongest stent., Conclusion: Susceptibility to LSD varies depending on length of malapposed segment when tested using a clinically relevant model as in this study. The mechanisms behind the susceptibility are likely multifactorial, including connector number, strut thickness, connector alignment and ring orientation but remain to be elucidated., Competing Interests: Competing interests: None declared.

Background: There is conflicting evidence regarding the incidence of longitudinal stent deformation (LSD) in contemporary practice., Methods and Results: To assess the incidence and mechanism of LSD across commonly used DES platforms, we performed a case-by-case review of 1,800 PCI cases involving 450 consecutive procedures using Biomatrix Flex, Resolute Integrity, Promus Element, and Xience V stents, respectively, between January 2009 and December 2011. LSD was detected in a higher proportion with Promus Element [15 (3.1%)] compared with other platforms (Xience V [4 (0.9%)], Biomatrix [3 (0.7%)], Resolute [3 (0.7%)]; P = 0.002). LSD was characterized as guide catheter/guide extension induced, or as impact from secondary devices such as postdilatation balloons or IVUS catheters. The incidence of guide catheter/guide extension LSD was similar across platforms; (Promus Element [5 (1.1%)], Xience V [4 (0.9%)], Biomatrix [3 (0.7%)], Resolute [3 (0.7%)]; P = 0.85). Secondary device LSD occurred exclusively with Promus Element (9/450 cases [2%] (P < 0.0001). Re-entering the deformed stent was more difficult in cases of secondary device LSD (6/9 compared with 0/12 treated cases; P < 0.001). Univariate predictors of LSD were previous CABG, culprit vessel, ostial involvement, and lesion tortuosity. Multivariate predictors of LSD were the Promus Element stent (OR 5.53 CI[1.54-19.85]), Guideliner use (OR 22.09 CI[4.73-103]), postdilation balloons (OR 5.47 CI[1.31-22.81]) and number of stents deployed (OR 2.06 CI[1.45-2.9]., Conclusion: LSD is more common than previously reported. LSD by a guide catheter/guide extension occurred equally with all platforms, however, LSD associated with secondary devices only occurred with the Element stent. These findings have important implications regarding current and future stent designs., (© 2015 Wiley Periodicals, Inc.)

Longitudinal stent deformation is defined as a compression of stent length after its implantation. It's a rare complication but dangerous seen with several stents. We reported a case of longitudinal stent deformation during bifurcation lesion treatment with a Promus Element(®) and we perform a short review of this complication., (Copyright © 2014 Elsevier Masson SAS. All rights reserved.)

Objective: To evaluate the axial integrity of different coronary stents using intravascular ultrasound (IVUS)., Background: Longitudinal stent deformation was recently reported., Methods: Consecutive patients who underwent IVUS analysis after drug-eluting stent (DES) implantation for de novo coronary lesions were evaluated. Stent length was compared with label length for calculation of absolute change and relative difference (absolute change divided by label length)., Results: A total of 233 DES utilizing five different platforms were included. The median absolute change in stent length was 0.90 mm (interquartile range [IQR] 0.48-1.39) and the relative difference was 5.24% (IQR 2.55-8.29). There was no significant difference among the groups in median absolute or relative change: Cypher 0.89 mm/3.89%, Taxus 0.88 mm/5.39%, Endeavor 1.16 mm/6.77%, Xience V 0.86 mm/5.80%, and PROMUS Element 0.79 mm/5.34% (P = 0.085, P = 0.072, respectively). Multivariate logistic regression revealed that the Cypher stent was independently correlated with a lower change in length, whereas stent label length and deployment pressure were correlated with higher absolute change., Conclusion: The axial integrity of DES platforms examined in vivo was high, with only mild changes in stent length after implantation. While there are differences between first- and second-generation DES, axial integrity among second-generation DES was similar., (© 2013 Wiley Periodicals, Inc.)

Background: Longitudinal stent deformation (LSD) in drug-eluting stents (DES) has been described as a disruption of stent structure. This study aimed to compare first- versus second-generation DES with respect to their actual stent length post deployment., Methods: A total of 617 DES for de novo coronary lesions in 552 patients were analyzed. Intravascular ultrasound (IVUS) was utilized to compare the degree and rate of LSD among six different DES types. IVUS-measured stent length was compared to the labeled length for calculation of absolute difference in stent length and relative absolute difference (absolute difference divided by the labeled length)., Results: The baseline characteristics were comparable between groups, except for higher calcification in the sirolimus-eluting stent (SES) group (p=0.037). The absolute and relative difference in length showed the lowest degree in the SES group and the highest degree in the Endeavor zotarolimus-eluting stent group (p=0.085 and 0.078, respectively). The percentage of more than 5% relative absolute difference was the lowest in the SES group compared to the other groups (p=0.018). However, the percentage of significant (>15%) relative absolute difference was similar among groups (p=0.99). In multivariate linear regression analysis, labeled stent length and stent diameter, but not stent type, were identified as independent correlates to the absolute and relative difference in the actual stent length post-deployment., Conclusion: This IVUS analysis confirms that among second-generation DES, there is overall similar frequency and severity of LSD when deploying in common coronary lesions., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Several recent reports have described the occurrence of longitudinal stent deformation (LSD, defined as the distortion or shortening of a stent along the longitudinal axis), following its successful deployment. However, few reports have described LSD prior to any stent deployment. This previously unrecognized complication is the result of modifications to stent design. It has been noted that the new-generation stent platforms have a reduced number of connectors, which in turn causes a reduction in longitudinal stent strength. To corroborate previous findings by our lab and others (Vijayvergiya et al, 2013), we describe here two cases of LSD prior to stent deployment that occurred due to crushing of the proximal stent edge by the guide catheter while attempting to withdraw the crimped stent. In addition, we discuss the associated risk factors, such as the length of the stent, and specific management strategies, including technical guidelines and use of fluoroscopic guidance for maneuvering the stent during the procedure.