High-pressure Balloon Inflation Research Articles

An algorithmic approach to balloon undilatable coronary lesions.

Balloon undilatable lesions are lesions that have been successfully crossed by both a guidewire and a balloon but cannot be expanded despite multiple high-pressure balloon inflations. Balloon undilatable lesions can be de novo or in-stent. We describe a systematic, algorithmic approach to treat both de novo and in-stent balloon undilatable lesions using various techniques, such as high-pressure balloon inflation, plaque modification balloons, intravascular lithotripsy, very high-pressure balloon inflation, coronary atherectomy, laser coronary angioplasty, and extraplaque lesion crossing. Knowledge of the various techniques can increase the efficiency, success and safety of the procedure.

Excimer Laser coronary atherectomy as adjunctive treatment of severe stent underexpansion with bulky calcification

Excimer Laser coronary atherectomy has improved significantly in recent years, emitting high-energy ultraviolet and short wavelength with less penetration and heat emission, ultimately leading to less tissue damage and fewer complications. We described a case of a 66-year-old male patient, former smoker and suffering from hypertension, diabetes mellitus, and dyslipidemia. He underwent multiple percutaneous coronary interventions in the left anterior descending artery with bare metal and drug-eluting stents. In the last percutaneous coronary intervention, the stent was underexpanded and the patient presented acute stent thrombosis and recurrent stent restenosis. New percutaneous coronary interventions with adjunctive Excimer Laser coronary atherectomy were undertaken due to refractory angina, using progressive load and saline injection, followed by subsequent high-pressure balloon inflation and drug-eluting stent implantation with an excellent result. At 8-month follow-up, the patient was asymptomatic.

Incidence and Characteristics of Incomplete Stent Apposition in Calcified Lesions: An Optical Coherence Tomography Study

BackgroundPersistent or late acquired incomplete stent apposition (ISA) may be associated with late or very late stent thrombosis following drug-eluting stent implantation. Presence of calcium at the target lesion may increase the risk of ISA even after rotational atherectomy (RA) followed by stenting with high pressure balloon inflation. The aim of this study is to examine the incidence and characteristics of ISA in heavily calcified lesions. MethodsA total of 52 heavily calcified coronary artery lesions requiring RA plus stenting were selected and studied. After successful ablation followed by stent implantation, optical coherence tomography (OCT) was performed to assess stent expansion and apposition. Presence or absence of ISA was examined and maximal stent strut to vessel wall distance (max SV distance) was measured. In lesions with repeated OCT at follow-up, serial changes in ISA were investigated. ResultsISA was documented in 51 of 52 (98%) lesions. Mean max SV distance was 713 ± 371 μm. In lesions with serial OCT images (n = 11), max SV distance decreased significantly (692.1 ± 420.2 to 462.5 ± 387.0 μm, P < 0.01) but persisted in all but 2 lesions (82%). ConclusionsISA is frequently documented in heavily calcified lesions requiring RA. Significant ISA still persisted with minimal improvement in SV distance at follow-up. Prognostic impact of the persistent ISA in such calcified lesions needs further investigations.

Case Report: Role of Rotational Atherectomy in Complex PCI

Background : One in three patients undergoing percutaneous coronary intervention (PCI) exhibits moderate or severe coronary artery calcification. Coronary calcification remains a major independent predictor of PCI failure and adverse outcomes. PCI of calcified coronary lesions remains challenging, despite significant improvements in the available tools and techniques. Rotational Atherectomy (RA) is a critical component to improve PCI success in these situations by producing lumen enlargement by physical removal of plaque and reduction in plaque rigidity, thus facilitating dilation Case Illustration: A 73-year-old man with exertional angina was referred to our hospital, with a history of hypertension, diabetes mellitus, ex-smoker and dyslipidemia. Physical exam, electrocardiogram, chest x-rays, and laboratory findings were unremarkable, but transthoracic echocardiogram revealed anterior wall hypokinesis. History of cardiac catheterization outside of our center with angiographic result of left anterior descending (LAD) lesion, highly calcified, non-dilatable on first several POBA attempts. Coronary angiography at our center, revealed diffuse calcification from proximal to distal of the LAD artery with about 90% maximum stenosis in mid LAD. RA (Rotablator, Boston) was then performed with A 1.50 mm burr gradually advanced at 150,000 rpm to passed the lesion. After deployments of stents, final angiogram showed well positioned stents with good distal run-off flow. The patient was uneventful during the procedure and was discharged following day. Discussion: In experienced hands, RA is as safe as standard PCI. RA is as a tool to make PCI possible in complex lesions with moderate or severe calcification when clinical variables make PCI appropriate. Rotablator is a catheter-based interventional cardiology procedure using a high-speed rotational device designed to ablate atherosclerotic plaque and restore luminal patency. This help to facilitate stent delivery, avoiding the barotrauma caused by repeated high-pressure balloon inflations that can lead to vessel dissection or perforation. Atherectomy can be performed safely with optimal burr selection and proper ablation techniques, and as a result, complication rates have been significantly minimized, with few changes in the acute complications reported in contemporary studies.

Efficacy and safety of shockwave intravascular lithotripsy (S-IVL) in calcified unprotected left main percutaneous coronary intervention - short-term outcomes.

IntroductionLeft main (LM) disease is associated with a large myocardial ischemic territory. Calcification with co-existing undilatable lesions is a predictor of poor clinical outcomes following LM percutaneous coronary interventions (PCI).AimTo evaluate the safety and efficiency of shockwave intravascular lithotripsy (S-IVL) in highly calcified LM diseases.Material and methodsThe study population consisted of sixteen patients qualified for PCI – mainly males (81.3%) with coronary artery disease (CAD) treated with left main S-IVL PCI due to unsuccessful attempts of plaque modification with a non-compliant (NC) balloon catheter, or rotational devices. Clinical success was defined as effective stent delivery and deployment (with less than < 20% in-stent residual stenosis) with preserved coronary flow TIMI-3 (Thrombolysis in Myocardial Infarction) at the end of the procedure.ResultsThe most frequent indication for PCI was acute coronary syndrome (ACS) (62.5%). In these high-risk (average Syntax score 24) patients, clinical success of PCI was achieved in 100% of cases. In the short-term observation, we recorded two major adverse cardiac and cerebrovascular events (MACCE) including one fatal, acute stent thrombosis.ConclusionsOur data suggest that the use of S-IVL is safe and effective as a bail-out strategy to manage LM lesions resistant to high-pressure NC balloon inflation. Despite encouraging initial results, future large studies with long-term observation are required to evaluate the safety and efficacy of S-IVL in LM stenosis.

Evaluation of safety and efficacy of coronary intravascular lithotripsy for treatment of severely calcified coronary stenoses: Design and rationale for the Disrupt CAD III trial

Coronary calcification limits optimal stent expansion and apposition and worsens safety and effectiveness outcomes of percutaneous coronary intervention (PCI). Current ablative technologies that modify calcium to optimize stent deployment are limited by guidewire bias and periprocedural complications related to atheroembolization, coronary dissection, and perforation. Intravascular lithotripsy (IVL) delivers pulsatile ultrasonic pressure waves through a fluid-filled balloon into the vessel wall to modify calcium and enhance vessel compliance, reduce fibroelastic recoil, and decrease the need for high-pressure balloon (barotrauma) inflations. IVL has been used in peripheral arteries as stand-alone revascularization or as an adjunct to optimize stent deployment. STUDY DESIGN AND OBJECTIVES: Disrupt CAD III (clinicaltrials.gov identifier: NCT03595176) is a prospective, multicenter, single-arm study designed to assess safety and efficacy of the Shockwave coronary IVL catheter to optimize coronary stent deployment in patients with de novo calcified coronary stenoses. The primary safety end point is freedom from major adverse cardiovascular events (composite of cardiac death, myocardial infarction, and target vessel revascularization) at 30 days compared to a prespecified performance goal. The primary effectiveness end point is procedural success without in-hospital major adverse cardiovascular events. Enrollment will complete early in 2020 with clinical follow-up ongoing for 2 years. CONCLUSION: Disrupt CAD III will evaluate the safety and effectiveness of the Shockwave coronary IVL catheter to optimize coronary stent deployment in patients with calcified coronary stenoses.

Bioprosthetic Valve Remodeling of Trifecta Surgical Valves to Facilitate Valve-in-Valve TAVR

ABSTRACT Background: Valve-in-valve transcatheter aortic valve replacement (VIV TAVR) is an effective treatment for high-risk patients with failed surgical bioprosthetic valves, but may be complicated by patient-prosthesis mismatch (PPM). We describe a novel technique – bioprosthetic valve remodeling (BVR) – to distort the frame of Trifecta surgical valves with a high-pressure balloon inflation, allowing for improved expansion and hemodynamics of the transcatheter heart valve (THV). Methods: We performed bench testing of BVR by deploying Portico THVs (Abbott, Minneapolis, MN, USA) inside Trifecta GT valves both at baseline and following BVR. Fluoroscopic and video imaging was performed to assess Trifecta frame distortion, THV expansion, and leaflet motion. Hydrodynamic testing was performed to determine transvalvular gradient under baseline conditions and following BVR. We performed 6 clinical cases of VIV TAVR with Evolut R THVs (Medtronic, Minneapolis, MN), followed by BVR. Hemodynamic measurements and calculation of the effective orifice area (EOA) were performed at baseline, immediately after implantation of the THV, and after BVR. Results: BVR resulted in an increase in the post-to-post diameter in Trifecta valves, and a lower transvalvular gradient after THV implantation. VIV TAVR and BVR was successful in all cases, with no major short-term complications. The mean baseline transvalvular gradient was 47.5 ± 14.4 mmHg, which was reduced to 21.0 ± 6.2 mmHg after THV implantation, and further reduced to 11.7 ± 4.1 mmHg following BVR. Gradients were stable at 1 month follow up. Conclusion: BVR distorts the frame of Trifecta valves, improving THV expansion and procedural hemodynamics of VIV TAVR.

Management of stent underexpansion using intravascular lithotripsy-Defining the utility of a novel device.

This study aimed to present a case series of patient treated for stent underexpansion resistant to conventional treatment with intravascular lithotripsy (IVL). Stent underexpansion is a powerful predictor of long-term stent patency and correlates with unfavorable clinical outcomes. This case series demonstrates the utility of IVL in managing stent underexpansion resistant to conventional treatment. We describe a case series of patients with stent underexpansion due to calcific coronary artery disease treated with IVL. Stent underexpansion was identified as an inability to adequately expand stents with conventional treatment. Only cases that failed to achieve adequate expansion with high-pressure noncompliant balloon inflation were included. Thirteen patients from six institutions have been included in this case series. The average age was 70.25 years with 76.9% of male patients. The average pre-IVL minimal stent area (MSA) was 2.71 mm2 , which improved to 6.44 mm2 post-IVL treatment, representing an average MSA gain of 238%. There were no procedural, peri-procedural, or 30-day major adverse cardiac and cerebrovascular event. This case series demonstrates that IVL is a feasible, safe alternative for the management of stent underexpansion due to calcific coronary disease.

A bail-out intervention: low-speed rotablation for management of an underexpanded stent causing recurrent stent restenosis

Background: Rotablation is used in heavily calcified lesions when balloon angioplasty fails to expand the lesion before stenting. Case Presentation: A 68-year-old male patient was admitted with angina 9 months after implantation of a 3.5 × 23 mm drugeluting stent in the crux of right coronary artery. Intravascular ultrasound revealed that the strut-to-strut diameter of the stent in the underexpanded region was 1.6 mm. High-pressure balloon inflation up to 26 atm was performed many times and the procedure was again completed with 3.0 and 3.5 mm kissing balloon inflation at 22 atm. After 4 months following the second procedure, the patient was admitted with the same symptoms. This time a 1.75 mm rotablator was used cautiously under low speed (150,000 rpm) to ablate the stent struts which handicap adequate expansion and lead to recurrent stenosis. Conclusion: Rotablation can also be used to fix an underexpanded stent if the other options fail.

Excimer Laser Atherectomy in the Management of Undilatable Coronary Stents

Introduction: Excimer laser has been reported to be safe and effective in the management of undilatable stents. We report our initial experience. Methods: From March 2016 to January 2019, 10 patients (ages 62-84, 9 male) were treated for constrained stents despite high-pressure balloon inflation (>26 atmospheres). Indications were threatened stent-thrombosis in 1 and recurrent restenosis (>3) with refractory symptoms in 9. All patients had clear angiographic evidence of a poorly expanded stent showing > 30% stent constraint, and 7 patients had multiple layers of stent. The procedure was performed under GA via 7F guiding catheter with a 0.9mm 80mJ/mm2/80Hz catheter (Spectranetics). Tissue debulking with a bloodless field was first performed followed by multiple contrast runs (average 6, 4-12). Lesions were post-dilated at >20 atmospheres and then treated with DEB. Target vessels included RCA (5), LAD (2), LCx (1), Intermediate (1), and SVG-to-1MCx (1). Results: Complete angiographic success (full stent-expansion, zero residual stenosis) occurred in 6 patients and partial-success (stent-constraint <15%, <30% residual stenosis) in 4. Multiple layers of stent were associated with partial-success. Micro-bubbles, slow-flow and pronounced ST-elevation occurred transiently in all patients. None required re-stenting. There were no procedural complications, all vessels had TIMI-3-flow and isoelectric ECGs on completion. Average next-day high-sensitivity-troponin-T level was 420ng/L. At 30-days and 1-year follow-up, there have been no deaths, and only one patient required TVR downstream in an untreated area 3 months later. Conclusion: Excimer laser represents a therapeutic option for the management of a small group of highly selected and symptomatic patients.

Prevalence, Presentation and Treatment of 'Balloon Undilatable' Chronic Total Occlusions: Insights from a Multicenter US Registry.

The prevalence, treatment and outcomes of balloon undilatable chronic total occlusions (CTOs) have received limited study. We examined the prevalence, clinical and angiographic characteristics, and procedural outcomes of percutaneous coronary interventions (PCIs) for balloon undilatable CTOs in a contemporary multicenter US registry. Between 2012 and 2017 data on balloon undilatable lesions were available for 425 consecutive CTO PCIs in 415 patients in whom guidewire crossing was successful: 52 of 425 CTOs were balloon undilatable (12%). Mean patient age was 65 ± 10 years and most patients were men (84%). Patients with balloon undilatable CTOs were more likely to be diabetic (67 vs. 41%, P < 0.001) and have heart failure (44 vs. 28%, P = 0.027). Balloon undilatable CTOs were longer (40 mm [interquartile range, IQR 20-50] vs. 30 [IQR 15-40], P = 0.016), more likely to have moderate/severe calcification (87 vs. 54%, P < 0.001), and had higher J-CTO score (3.2 ± 1.1 vs. 2.5 ± 1.3, P < 0.001) and PROGRESS-CTO complications score (3.9 ± 1.7 vs. 3.1 ± 2.0, P < 0.005). They were associated with lower technical and procedural success (92 vs. 98%, P = 0.024; and 88 vs. 96%, P = 0.034, respectively) and higher risk for in-hospital major adverse events (8 vs. 2%, P = 0.008) due to higher perforation rates. The most frequent treatments for balloon undilatable CTOs were high pressure balloon inflations (64%), rotational atherectomy (31%), laser (21%), and cutting balloons (15%). Balloon undilatable CTOs are common and are associated with lower success and higher complication rates.

Bioprosthetic Valve Fracture During Valve-in-valve TAVR: Bench to Bedside.

Valve-in-valve (VIV) transcatheter aortic valve replacement (TAVR) has been established as a safe and effective means of treating failed surgical bioprosthetic valves (BPVs) in patients at high risk for complications related to reoperation. Patients who undergo VIV TAVR are at risk of patient-prosthesis mismatch, as the transcatheter heart valve (THV) is implanted within the ring of the existing BPV, limiting full expansion and reducing the maximum achievable effective orifice area of the THV. Importantly, patient-prosthesis mismatch and high residual transvalvular gradients are associated with reduced survival following VIV TAVR. Bioprosthetic valve fracture (BVF) is as a novel technique to address this problem. During BPV, a non-compliant valvuloplasty balloon is positioned within the BPV frame, and a highpressure balloon inflation is performed to fracture the surgical sewing ring of the BPV. This allows for further expansion of the BPV as well as the implanted THV, thus increasing the maximum effective orifice area that can be achieved after VIV TAVR. This review focuses on the current evidence base for BVF to facilitate VIV TAVR, including initial bench testing, procedural technique, clinical experience and future directions.

The Odyssey of TAVR from concept to clinical reality.

On 16 April 2002, my colleagues and I performed, in an inoperable and desperately ill man with critical calcific aortic stenosis (AS), the first clinical percutaneous implantation of an aortic valve bioprosthesis. As of 2013, more than 80,000 patients have been treated; and transcatheter aortic valve replacement (TAVR), so strongly criticized by all the experts throughout the early years, continues to grow in parallel with its constant technological improvements. Transcatheter aortic valve replacement can now be recognized as a medical breakthrough. It is a revolutionary technology that meets an unfulfilled clinical need for a common disease, is validated by rigorous evidence-based studies, and is applicable worldwide. We report here the main phases of this 20-year odyssey and briefly consider the prospects of TAVR, which remains in continuous development.

Un-Retrieved Deformed Biodegradable Polymer Coated Drug Eluting Stent after Percutaneous Coronary Intervention to Complete Occluded Right Coronary Artery: Patient at 8 Months Angiographic Follow-Up

Balloon rupture during stent deployment is rare, and can cause stent damage upon its retrieval. We described a case of inadequate drug-eluting stent expansion in a fibrotic and calcified mid right coronary artery lesion despite pre-treatment with high pressure balloon inflation, with rupture and entrapment of the balloon within the stent. Attempts of retrieval of the ruptured balloon caused severe deformity of the distal segment of the stent. The stent could not be crushed or retrieved, and was left in situ. Angiographic follow-up at 8 months time showed widely patent vessel.

Excimer Laser LEsion Modification to Expand Non-dilatable sTents: The ELLEMENT Registry

Stent underexpansion is a risk factor for in-stent restenosis and stent thrombosis. Existing techniques to optimize stent expansion are sometimes ineffective. The aim of this study was to evaluate the effectiveness and feasibility of Excimer Laser Coronary Angioplasty (ELCA) in improving stent expansion when high-pressure non-compliant balloon inflation was ineffective. ECLA ablation was performed at high energy during contrast injection and only within the underexpanded stent. The primary endpoint of successful laser dilatation was defined as an increase of at least 1mm(2) in minimal stent cross-sectional area (MSA) on IVUS or an increase of at least 20% in minimal stent diameter (MSD) by QCA, following redilatation with the same non-compliant balloon that had been unsuccessful prior to ELCA. Secondary endpoints were cardiac death, myocardial infarction (MI) and target lesion revascularization. Between June 2009 and November 2011, 28 patients with an underexpanded stent despite high-pressure balloon inflation were included. The mean laser catheter size was 1.2±0.4 (range 0.9-2.0mm) and a mean of 62±12mJ/mm(2) at 62±21hertz were required for optimal expansion. Laser-assisted stent dilatation was successful in 27 cases (96.4%), with an improvement in MSD by QCA (1.6±0.6mm at baseline to 2.6±0.6mm post-procedure) and MSA by IVUS (3.5±1.1mm(2) to 7.1±1.9mm(2)). Periprocedural MI occurred in 7.1%, transient slow-flow in 3.6% and ST elevation in 3.6%. During follow-up, there were no MIs, there was 1 cardiac-death, and TLR occurred in 6.7%. The ELLEMENT study confirms the feasibility of ELCA with contrast injection to improve stent underexpansion in undilatable stented lesions.

Prolonged high‐pressure is required for optimal stent deployment as assessed by optical coherence tomography

Optimizing stent deployment is important for both acute- and long-term outcomes. High-pressure balloon inflation is the standard for coronary stent implantation. However, there is no standardized inflation protocol. We hypothesized that prolonged high-pressure balloon inflation until stabilization of inflation pressure is superior to a rapid inflation/deflation sequence for both stent expansion and strut apposition. A high-pressure rapid inflation/deflation sequence was deployed followed by angiography to assure no residual stenosis. Optical coherence tomography (OCT) was then performed followed by prolonged inflation until balloon pressure was stabilized for 30 sec using the same balloon at the same pressure as the rapid sequence. A second OCT run was then done. Thirteen thousand nine hundred thirteen stent struts were evaluated by OCT in 12 patients undergoing successful stenting. Stent expansion improved with prolonged (206 ± 115 sec) vs. rapid (28 ± 17 sec) inflation for both minimal stent diameter (3.0 ± 0.5 vs. 2.75 ± 0.44 mm, P < 0.0001) and area (7.83 ± 2.45 vs. 6.63 ± 1.85 mm(2) , P = 0.0003). The number of malapposed struts decreased (45 ± 41 vs. 88 ± 75, P = 0.005) as did the maximal malapposed strut distance (0.31 ± 0.2 vs. 0.43 ± 0.2 mm, P = 0.0001). Factors related to strut malapposition after rapid inflation included localized asymmetry in 67%, stent underexpansion in 75%, and stent undersizing in 67%. These data demonstrate that prolonged inflation is superior to a rapid inflation/deflation technique for both stent expansion and strut apposition. We recommend for routine stent deployment a prolonged inflation protocol as described above to optimize stent deployment.

The impact of fractional flow reserve measurement on clinical outcomes after transradial coronary stenting

Fractional flow reserve (FFR) ≥0.96 after stenting correlates well with an optimal stent expansion, but outcomes based on FFR after drug eluting stents (DES) have not been studied. This study sought to investigate the proportion of patients in whom an FFR ≥0.96 can be achieved after transradial stenting using primarily DES and to determine outcomes based on a post-stent FFR ≥0.96 vs. an FFR<0.96. A total of 66 patients with single-vessel disease and FFR<0.75 underwent transradial stenting. After stenting, FFR was <0.96 in 34 patients and there was a hyperaemic trans-stent gradient across the edges of stent in five patients; after high-pressure balloon inflation, FFR increased to ≥0.96 in three patients and an FFR ≥0.96 was achieved in 35 patients (53%, group 1), but FFR remained <0.96 in 31 patients (47%, group 2). There was no correlation between FFR and minimum lumen diameter in group 1 or group 2 (r=0.03; p=0.72 and r=0.02; p=0.22, respectively). The 24-month event-free survival estimate defined as freedom from death, MI, and target vessel revascularisation (PCI or CABG) was significantly greater in group 1 than in group 2 (94% versus 72%, respectively; p=0.02). After transradial stenting with predominately DES, an FFR ≥0.96 was achieved in only 53% of patients and event rates among patients with a post-stent FFR ≥0.96 were significantly lower than those with an FFR<0.96.

Catheter Interventions for Kawasaki Disease: Current Concepts and Future Directions

During the past 15 years, clinical experience with catheter interventional treatment in patients with Kawasaki disease, including balloon angioplasty, stent implantation, rotational ablation, and transluminal coronary revascularization, has been gradually increasing. Because the coronary artery lesions in Kawasaki disease involve severe calcifications, the indications or catheter intervention techniques have not been established for adult patients with Kawasaki disease. Satisfactory acute results for coronary balloon angioplasty have been obtained in patients with a relatively short interval from the onset of disease, especially within 6 years; however, the incidence of restenosis after angioplasty is still high. Rotational ablation may be the most appropriate catheter intervention technique for patients with Kawasaki disease. The advantage of rotational ablation is the high success rate, even in patients with calcified coronary artery stenosis. Stent implantation requires larger arterial access and is not possible in younger children. Care should be paid to the detection of newly-formed aneurysms, as the formation of new aneurysms is associated with the use of additional balloon angioplasty using high pressure balloon inflation. Anticoagulation or anti-platelet regimens are essential for long-term management. Coronary intervention in Kawasaki disease requires special techniques and knowledge of cardiovascular involvement. The procedure should be managed under the close collaboration between pediatric cardiologists and coronary interventional cardiologists.

Rotational atherectomy of a complex, highly calcified left anterior descending artery lesion

Abstract Rotational atherectomy (RA) is an advanced coronary debulking technique, often used in cases, where traditional percutaneous coronary intervention (PCI) methods (e.g. balloon predilatation, use of cutting balloons, direct stenting etc.) are inadequate. We report a case of a male patient, who previously underwent PCI of the right coronary artery (RCA) and was free of chest pain for several weeks, but his clinical symptoms have developed again. Angiography showed a “de novo”, highly calcified left anterior descending (LAD) lesion that, after high-pressure balloon inflation, failed to dilate, thus the intervention was suspended. RA was scheduled for the patient within one month. As a complication of the previous LAD dilatation attempt, a chronic dissection of the target lesion occurred. Problems arose during the direct wiring attempt of the main vessel and the true lumen was only found via plaque modification, after accessing a small septal branch. Accessing the true lumen was only possible by using a conventional cross-wire. This was exchanged to a RA wire, with the help of an over-the-wire (OTW) balloon catheter. RA and debulking of the target lesion was performed. An everolimus-eluting stent (BioMatrix, Biosensors Europe, Morges, Switzerland) was implanted, with excellent results. The patient is free of clinical symptoms since the intervention, which took place 14 months ago.

High energy excimer laser to treat coronary in‐stent restenosis in an underexpanded stent

Balloon refractory calcific coronary plaques remain a technical challenge. Stent underexpansion is known as a major cause of restenosis and thrombosis. We report a case of in-stent restenosis 5 months after stent suboptimal implantation in a noncompliant calcific atherosclerotic plaque which could not be disrupted by repeated prolonged high-pressure balloon inflations. High-energy excimer laser use altered underlying lesion morphology, allowing full stent apposition. Advances in equipment and technique have allowed more frequent use of high energy excimer laser technology during percutaneous coronary angioplasty with very low rates of complications. Laser technology represents a useful tool to overcome resistant lesions during percutaneous coronary interventions.