Percutaneous coronary intervention for small vessel coronary artery disease

Comparison of Small Blood Vessel Diameter with Intravascular Ultrasound and Coronary Angiography for Guidance of Percutaneous Coronary Intervention

Major cardiovascular events (MACEs) are a cause of major mortality worldwide. The narrowing and blockage of coronary arteries with atherosclerotic plaques are diagnosed and treated with percutaneous coronary intervention (PCI). During this procedure, coronary angiography (CAG) remains the most widely used guidance modality for the evaluation of the affected blood vessel. The measurement of the blood vessel diameter is an important factor to consider in order to decide if stent colocation is suitable for the intervention. In this regard, a small blood vessel (<2.75 mm) is majorly left without stent colocation; however, small vessel coronary artery disease (SvCAD) is a significant risk factor for the recurrence of MACEs, maybe due to the lack of a standardized treatment related to the diameter of the affected blood vessel; therefore, a more precise measurement is needed. The use of CAG for the measurement of the blood vessel diameter has some important limitations that can be improved with the use of newer techniques such as intravascular ultrasound (IVUS), although at higher costs, which might explain its underuse. To address differences in blood vessel diameter measurements and identify specific cases where IVUS might be of additional benefit for the patient, we conducted a retrospective study in patients who underwent PCI for MACEs with affection for at least one small blood vessel. We compared the measurements of the affected small blood vessels' diameter obtained by CAG and IVUS to identify cases of reclassification of the affected blood vessel; additionally, we underwent a multivariate analysis to identify risk factors associated with blood vessel reclassification. We included information from 48 patients with a mean ± SD age of 69.1 ± 11.9 years; 70.8% were men and 29.2% were women. The mean diameter with CAG and IVUS was 2.1 mm (95% CI 1.9-2.2), and 2.8 (2.8-3.0), respectively. The estimated difference was of 0.8 mm (95% CI 0.7-0.9). We found a significant positive low correlation in diameter measurements of small blood vessels obtained with CAG and IVUS (r = 0.1242 p = 0.014). In total, 37 (77%) patients had a reclassification of the affected blood vessel with IVUS. In 21 cases, the affected blood vessel changed from a small to a medium size (2.75-3.00 mm), and in 15 cases, the affected vessel changed from a small to a large size (<3.00 mm). The Bland-Altman plot was used to evaluate agreement in measurements with CAG and IVUS. The change in blood vessel classification with IVUs was important for the decision of intervention and stent collocation. The only variable associated with reclassification of blood vessels after adjustment in a multivariate analysis was T2D (type 2 diabetes) (p = 0 0.035). Our findings corroborate that blood vessels might appear smaller with CAG, especially in patients with T2D; therefore, at least in these cases, the use of IVUS is recommended over CAG.

Cardio-respiratory motion compensation for coronary roadmapping in fluoroscopic imaging

BACKGROUND

Inferring the shape and position of coronary artery poses challenges when using fluoroscopic image guidance during percutaneous coronary intervention (PCI) procedure. Although angiography enables coronary artery visualization, the use of injected contrast agent raises concerns about radiation exposure and the risk of contrast-induced nephropathy. To address these issues, dynamic coronary roadmapping overlaid on fluoroscopic images can provide coronary visual feedback without contrast injection.

PURPOSE

This paper proposes a novel cardio-respiratory motion compensation method that utilizes cardiac state synchronization and catheter motion estimation to achieve coronary roadmapping in fluoroscopic images.

METHODS

For more accurate cardiac state synchronization, video frame interpolation is applied to increase the frame rate of the original limited angiographic images, resulting in higher framerate and more adequate roadmaps. The proposed method also incorporates a multi-length cross-correlation based adaptive electrocardiogram (ECG) matching to address irregular cardiac motion situation. Furthermore, a shape-constrained path searching method is proposed to extract catheter structure from both fluoroscopic and angiographic image. Then catheter motion is estimated using a cascaded matching approach with an outlier removal strategy, leading to a final corrected roadmap.

RESULTS

Evaluation of the proposed method on clinical x-ray images demonstrates its effectiveness, achieving a 92.8% F1 score for catheter extraction on 589 fluoroscopic and angiographic images. Additionally, the method achieves a 5.6-pixel distance error of the coronary roadmap on 164 intraoperative fluoroscopic images.

CONCLUSIONS

Overall, the proposed method achieves accurate coronary roadmapping in fluoroscopic images and shows potential to overlay accurate coronary roadmap on fluoroscopic image in assisting PCI.

Comparison of Clinical Outcomes Among Various Percutaneous Coronary Intervention Strategies for Small Coronary Artery Disease

It remains unclear which percutaneous coronary intervention (PCI) strategy is the most preferable in patients with small-vessel coronary artery disease (CAD). We sought to evaluate the clinical efficacy of various PCI strategies for patients with small-vessel CAD through a network meta-analysis of randomized controlled trials (RCTs). We searched multiple databases for RCTs investigating the efficacy of the following PCI strategies for small-vessel CAD (<3 mm in diameter): drug-coated balloons (DCB), early-generation paclitaxel-eluting stents and sirolimus-eluting stents (SES), newer-generation drug-eluting stents (DES), bare-metal stents (BMS), cutting balloon angioplasty, and balloon angioplasty (BA). The primary outcome was the trial-defined major adverse cardiovascular events (MACE), mostly defined as a composite of death, myocardial infarction, and revascularization. The secondary outcomes included each component of MACE and angiographic binary restenosis. We performed a sensitivity analysis for RCTs without BMS or first-generation DES. Our search identified 29 eligible RCTs, including 8,074 patients among the 8 PCI strategies. SES significantly reduced MACE compared with BA (hazard ratio 0.23, 95% confidence interval 0.10 to 0.54) with significant heterogeneity (I2 = 55.9%), and the rankogram analysis showed that SES was the best. There were no significant differences between DCB and newer-generation DES in any clinical outcomes, which was consistent in the sensitivity analysis. BMS and BA were ranked as the worst 2 for most clinical outcomes. In conclusion, SES was ranked as the best for reducing MACE. There were no significant differences in clinical outcomes between DCB and newer-generation DES. BMS and BA were regarded as the worst strategies for small-vessel CAD.

Percutaneous coronary intervention with ridaforolimus eluting-stents in small vessel coronary artery disease

INTRODUCTION

The ridaforolimus-eluting stent (RES) system uses a novel cobalt alloy-based coronary stent with a durable elastomeric polymer eluting ridaforolimus.

AIM OF STUDY

To assess the safety and efficacy of small diameter (2.25 mm) RES (EluNIR) in small coronary artery disease.

METHODS

A prospective, multicenter, single-arm, open-label clinical trial. Clinical follow-up was performed at 30 days, 6 months, and 1 year after the procedure. Target lesions were located in native coronary arteries or bypass graft conduits, with visually estimated diameter of ≥2.25 mm to ≤2.5 mm. The primary endpoint was combined device success, defined as final in-stent residual diameter stenosis <30%, without 30-day major adverse cardiovascular events (MACE).

RESULTS

A total of 81 patients were enrolled in the study. Twenty-three patients (28%) had acute coronary syndrome (ACS) at presentation and 37 (46%) had prior myocardial infarction (MI). Most of the target lesions were located in the circumflex coronary artery (44%) and were classified as B2/C grade according to the American Heart Association/American College of Cardiology classification. The final mean minimal lumen diameter, mean reference vessel diameter, and mean residual percent diameter stenosis were 2.0 ± 0.2 mm, 2.3 ± 0.1 mm, and 14 + 6.6%, respectively. The primary endpoint of device success without 30-day MACE was achieved in 98.8% of the patients. Target lesion failure (TLF) at 6 months was 1.2%. Thirty-day and 1-year MACE rates were 1.2% and 2.5%, respectively.

CONCLUSION

The EluNIR 2.25 mm stent shows excellent results in small coronary artery disease and adds another tool in the treatment of this complex lesion type.

The clinical utility of circulating cell division control 42 in small-vessel coronary artery disease patients undergoing drug-coated balloon treatment

BACKGROUND

Cell division control 42 (CDC42) regulates atherosclerosis, blood lipids, and inflammation and thus affects coronary artery disease (CAD), but its utility in drug-coated balloon (DCB)-treated small-vessel CAD (SV-CAD) patients is unclear. This study intended to evaluate the change and prognostic role of CDC42 in SV-CAD patients underwent DCB.

METHODS

Serum CDC42 was measured by enzyme-linked immunosorbent assay in 211 SV-CAD patients underwent DCB at baseline, day (D) 1, D3, and D7, as well as in 50 healthy controls (HCs).

RESULTS

CDC42 was decreased in SV-CAD patients compared to HCs (P < 0.001), and it was negatively associated with total cholesterol (P = 0.015), low-density lipoprotein cholesterol (P = 0.003), C-reactive protein (P = 0.001), multivessel disease (P = 0.020), and American college of cardiology/American heart association type B2/C lesions (P = 0.039) in SV-CAD patients. Longitudinally, CDC42 decreased from baseline to D1 and then gradually increased to D7 (P < 0.001) in SV-CAD patients after DCB. Interestingly, high CDC42 (cut-off value = 500 pg/mL) at baseline (P = 0.047), D3 (P = 0.046), and D7 (P = 0.008) was associated with a lower accumulating target lesion failure (TLF) rate; high CDC42 at D3 (P = 0.037) and D7 (P = 0.041) was related to a lower accumulating major adverse cardiovascular event (MACE) rate in SV-CAD patients underwent DCB. Importantly, CDC42 at D7 (high vs. low) independently predicted lower accumulating TLF (hazard ratio (HR) = 0.145, P = 0.021) and MACE (HR = 0.295, P = 0.023) risks in SV-CAD patients underwent DCB.

CONCLUSIONS

Circulating CDC42 level relates to milder disease conditions and independently estimates lower risks of TLF and MACE in SV-CAD patients underwent DCB, but further validation is still needed.

Drug-coated balloon: an effective alternative to stent strategy in small-vessel coronary artery disease-a meta-analysis

Background

Small-vessel coronary artery disease (CAD) is frequently observed in coronary angiography and linked to a higher risk of lesion failure and restenosis. Currently, treatment of small vessels is not standardized while having drug-eluting stents (DES) or drug-coated balloons (DCBs) as possible strategies. We aimed to conduct a meta-analytic approach to assess the effectiveness of treatment strategies and outcomes for small-vessel CAD.

Methods

Comprehensive literature search was conducted using PubMed, Embase, MEDLINE, and Cochrane Library databases to identify studies reporting treatment strategies of small-vessel CAD with a reference diameter of ≤3.0 mm. Target lesion revascularization (TLR), target lesion thrombosis, all-cause death, myocardial infarction (MI), and major adverse cardiac events (MACE) were defined as clinical outcomes. Outcomes from single-arm and randomized studies based on measures by means of their corresponding 95% confidence intervals (CI) were compared using a meta-analytic approach. Statistical significance was assumed if CIs did not overlap.

Results

Thirty-seven eligible studies with a total of 31,835 patients with small-vessel CAD were included in the present analysis. Among those, 28,147 patients were treated with DES (24 studies) and 3,299 patients with DCB (18 studies). Common baseline characteristics were equally distributed in the different studies. TLR rate was 4% in both treatment strategies [0.04; 95% CI 0.03-0.05 (DES) vs. 0.03-0.07 (DCB)]. MI occurred in 3% of patients receiving DES and in 2% treated with DCB [0.03 (0.02-0.04) vs. 0.02 (0.01-0.03)]. All-cause mortality was 3% in the DES group [0.03 (0.02-0.05)] compared with 1% in the DCB group [0.01 (0.00-0.03)]. Approximately 9% of patients with DES developed MACE vs. 4% of patients with DCB [0.09 (0.07-0.10) vs. 0.04 (0.02-0.08)]. Meta-regression analysis did not show a significant impact of reference vessel diameter on outcomes.

Conclusion

This large meta-analytic approach demonstrates similar clinical and angiographic results between treatment strategies with DES and DCB in small-vessel CAD. Therefore, DES may be waived in small coronary arteries when PCI is performed with DCB.

Clinical implication of ticagrelor monotherapy in patients with small vessel coronary artery disease: results from the TICO randomized trial

Background

The aim of this study was to evaluate the efficacy and safety of ticagrelor monotherapy in patients with small vessel disease compared with ticagrelor-based DAPT within the Ticagrelor Monotherapy after 3 Months in the Patients Treated with New Generation Sirolimus Eluting Stent for Acute Coronary Syndrome (TICO) trial population.

Methods

Reference vessel diameter ≤2.5 mm was considered as small vessel disease. We conducted a comparison of the incidence of target lesion failure (TLF) and Bleeding Academic Research Consortium (BARC) type 3 or 5 bleeding. TLF was defined as a composite of cardiac death, target lesion myocardial infarction, stent thrombosis, and target lesion revascularization.

Results

652 patients among 3,056 TICO population (21.3%) had small vessel disease. Patients with small vessel disease showed a higher rate of TLF compared to those without small vessel disease (2.9% vs. 1.0%, log-rank p < 0.001). The presence of small vessel disease emerged as an independent predictor for 1-year TLF (HR 2.84, 95% CI 1.54-5.25), while it did not show a significant association with bleeding complications. The 12-month TLF rate was 1.6% for ticagrelor monotherapy after 3-month DAPT, and 4.2% for ticagrelor-based 12-month DAPT (p = 0.059) in patients with small vessel disease (HR 0.38, 95% CI 0.14-1.04, p for interaction = 0.261). The incidence of BARC type 3 or 5 bleeding rate 2.5% for ticagrelor monotherapy after 3-month DAPT, and 5.6% for ticagrelor-based 12-month DAPT (p = 0.052) in patients with small vessel disease (HR 0.44, 95% CI 0.19-1.01, p for interaction = 0.322). In the 3-month landmark analysis, ticagrelor monotherapy significantly reduced BARC type 3 or 5 bleeding in patients with small vessel disease (HR 0.09, 95% CI 0.01-0.69, log-rank p = 0.005) while demonstrating a similar incidence of TLF compared to ticagrelor based 12-month DAPT during the 3-12 months period.

Conclusions

There are no significant interactions between the antiplatelet strategy regarding the 12-month incidence of ischemic and bleeding complications. Ticagrelor monotherapy demonstrated a reduction in bleeding complications after a 3-month period of DAPT without increasing the rate of TLF, when compared to ticagrelor-based 12-month DAPT, specifically in patients with small vessel disease. Clinical Trial Registration: www.ClinicalTrials.gov, identifier, NCT02494895.

Drug Coated Balloon in the Treatment of De Novo Coronary Artery Disease: A Narrative Review

Drug coated balloons (DCBs) are currently indicated in guidelines as a first choice option in the management of instant restenosis, whereas their use in de novo lesions is still debated. The concerns raised after the contrasting results of the initial trials with DCBs in de novo lesions have been more recently overcome by a larger amount of data confirming their safety and effectiveness as compared to drug-eluting stents (DES), with potentially greater benefits being achieved, especially in particular anatomical settings, as in very small or large vessels and bifurcations, but also in selected subsets of higher-risk patients, where a 'leave nothing behind' strategy could offer a reduction of the inflammatory stimulus and thrombotic risk. The present review aims at providing an overview of current available DCB devices and their indications of use based on the results of data achieved so far.

Revascularization and Medical Therapy for Chronic Coronary Syndromes: Lessons Learnt from Recent Trials, a Literature Review

Stable coronary artery disease (CAD) has recently been replaced by a new entity described as chronic coronary syndrome (CCS). This new entity has been developed based on a better understanding of the pathogenesis, the clinical characteristics, and the morbi-mortality associated to this condition as part of the dynamic spectrum of CAD. This has significant implications in the clinical management of CCS patients, that ranges from lifestyle adaptation, medical therapy targeting all the elements contributing to CAD progression (i.e., platelet aggregation, coagulation, dyslipidaemia, and systemic inflammation), to invasive strategies (i.e., revascularization). CCS is the most frequent presentation of coronary artery disease which is the first cardiovascular disease worldwide. Medical therapy is the first line therapy for these patients; however, revascularization and especially percutaneous coronary intervention remains beneficial for some of them. European and American guidelines on myocardial revascularization were released in 2018 and 2021, respectively. These guidelines provide different scenarios to help physicians choose the optimal therapy for CCS patients. Recently, several trials focusing on CCS patients have been published. We sought to synthetize the place of revascularization in CCS patients according to the latest guidelines, the lessons learnt from recent trials on revascularization and medical therapy, and future perspectives.

Clinical expert consensus document on drug-coated balloon for coronary artery disease from the Japanese Association of Cardiovascular Intervention and Therapeutics

Drug-coated balloon (DCB) technology was developed to deliver the antiproliferative drugs to the vessel wall without leaving any permanent prosthesis or durable polymers. The absence of foreign material can reduce the risk of very late stent failure, improve the ability to perform bypass-graft surgery, and reduce the need for long-term dual antiplatelet therapy, potentially reducing associated bleeding complications. The DCB technology, like the bioresorbable scaffolds, is expected to be a therapeutic approach that facilitates the "leave nothing behind" strategy. Although newer generation drug-eluting stents are the most common therapeutic strategy in modern percutaneous coronary interventions, the use of DCB is steadily increasing in Japan. Currently, the DCB is only indicated for treatment of in-stent restenosis or small vessel lesions (< 3.0 mm), but potential expansion for larger vessels (≥ 3.0 mm) may hasten its use in a wider range of lesions or patients with obstructive coronary artery disease. The task force of the Japanese Association of Cardiovascular Intervention and Therapeutics (CVIT) was convened to describe the expert consensus on DCBs. This document aims to summarize its concept, current clinical evidence, possible indications, technical considerations, and future perspectives.

Five-year clinical outcomes of a 2.25 mm sirolimus-eluting stent in Japanese patients with very small coronary artery disease: final results of the CENTURY JSV study

The aim of this study is to evaluate the long-term safety and efficacy of the 2.25 mm bioresorbable-polymer sirolimus-eluting Ultimaster stent in a Japanese patient population. Treatment of coronary artery disease in very small vessels is associated with an increased risk for cardiac events. The CENTURY JSV study is a prospective, multicenter, single-arm study. Seventy patients with stable and unstable coronary artery disease with a coronary lesion eligible for implantation with a 2.25 mm stent were enrolled in this study. Patients underwent clinical follow-up through 5-year after the PCI procedure. The mean age was 70.4 ± 9.2 years. The prevalence of diabetes mellitus was 37.1%, all not insulin dependent. The incidence of major adverse cardiac events, defined as cardiac death, target vessel myocardial infarction (MI), and clinically driven target lesion revascularization (CD-TLR) at 5 years was 5.7%. A non-Q wave MI was noted in 1.4% and 4.3% underwent a CD-TLR. There was no stent thrombosis during the entire follow-up period. No cardiac events were reported between 2 and 5 years. This is the first study to demonstrate safety and effectiveness for 5 years after treatment of very small coronary disease with 2.25 mm-diameter DES.Clinical trial registration: UMIN000012928.

Long-Term Outcomes With Drug-Eluting Balloon for the Treatment of In-Stent Restenosis and De Novo Lesions: The Novara-Biella-Trento (NOBITRE) Registry

Drug-coated balloons (DCBs) have emerged for percutaneous coronary interventions (PCI) of in-stent restenosis or particular anatomical subsets. We provide a real-world analysis of the prognostic determinants and long-term outcomes of patients treated with DCB for any lesion in a comprehensive multicenter registry. The primary study endpoint was the occurrence of major cardiovascular events (MACE: composite of all-cause death, myocardial infarction, and target vessel revascularization) at the longest available follow-up. We included 267 patients (196 treated for in-stent restenosis and 71 for de novo lesions), with a median follow-up of 616 [368–1025] days. MACE occurred in 70 (26.2%) of the patients and related with higher rates of in-stent restenosis (P = .04), longer and more type C lesions ( P = .05 and P = .04). At multivariate Cox-regression, type C lesions emerged as the only independent predictor of MACE (adjusted OR [95% CI] = 1.83[1.13–2.97], P = .014), mainly driven by target vessel revascularization (adjusted OR[95% CI] = 1.78[1.05–2.95], P = .03) not conditioning survival. In-stent restenosis emerged as major determinant of TLF (adjusted OR[95% CI] = 2.59[1.17–5.75], P = .02). DCBs represent a treatment option for any lesion; however, type C and restenotic lesions are associated with an increased risk of MACE and target lesion failure, where the optimal strategies for patients’ selection and lesion preparation are still undefined.

Sirolimus-coated balloon versus everolimus-eluting stent in de novo coronary artery disease: Rationale and design of the TRANSFORM II randomized clinical trial

BACKGROUND

Percutaneous coronary intervention (PCI) with drug-eluting stent (DES) implantation is a widely adopted strategy for the treatment of de novo coronary artery disease. DES implantation conveys an inherent risk for short- and long-term complications, including in-stent restenosis and stent thrombosis. Drug-coated balloons are emerging as an alternative approach to fulfill the "leaving nothing behind" principle and avoid long-term DES-related complications.

DESIGN

TRANSFORM II is an investigator-initiated, multicenter, noninferiority, randomized clinical trial, testing a sirolimus-coated balloon (SCB) versus the standard of care for native coronary vessels with a 2-3 mm diameter, in terms of 12-month target lesion failure (TLF; primary endpoint) and net adverse cardiovascular events (coprimary endpoint). Patients undergoing PCI will be randomized to be treated with either SCB or new-generation everolimus-eluting stent and will be followed up clinically for up to 60 months. Assuming a TLF rate of 8% at 12 months with DES, a sample size of 1325 patients was chosen to ensure an 80% power to detect a 1.5% lower incidence in the SCB group with a type I error rate of 0.05. The TRANSFORM II trial is registered on clinicaltrials.gov (identification number NCT04893291). Several substudies, including an optical coherence tomography assessment at 9 months (intracoronary imaging substudy), will investigate the study device in different clinical and lesion settings.

CONCLUSIONS

The randomized TRANSFORM II trial will determine whether a novel SCB is noninferior to a current everolimus-eluting stent when adopted for the treatment of de novo lesions in coronary vessels with a diameter between 2 and 3 mm.

Duration of Dual Antiplatelet Therapy After Implantation of Drug-Coated Balloon

The drug-coated balloon (DCB) is an emerging percutaneous coronary intervention (PCI) device with theoretical advantages and promising results. Recent clinical observations have demonstrated that DCB tends to have both good efficacy and a good safety profile in the treatment of in-stent restenosis (ISR) for both bare-metal and drug-eluting stents (DES), de novo coronary artery disease (CAD), and other situation, such as high bleeding risk, chronic total occlusion, and acute coronary syndrome (ACS). Dual antiplatelet therapy (DAPT) has become an essential medication in daily clinical practice, but the optimal duration of DAPT after the implantation of a DCB remains unknown. At the time of the first in vivo implantation of paclitaxel-DCB for the treatment of ISR in 2006, the protocol-defined DAPT duration was only 1 month. Subsequently, DAPT duration ranging from 1 to 12 months has been recommended by various trials. However, there have been no randomized controlled trials (RCTs) on the optimal duration of DAPT after DCB angioplasty. Current clinical guidelines normally recommend the duration of DAPT after DCB-only angioplasty based on data from RCTs on the optimal duration of DAPT after stenting. In this review, we summarized current clinical trials on DCB-only angioplasty for different types of CADs and their stipulated durations of DAPT, and compared their clinical results such as restenosis, target lesion revascularization (TLR) and stent thrombosis event. We hope this review can assist clinicians in making reasonable decisions about the duration of DAPT after DCB implantation.

Drug-coated Balloons for Small Coronary Disease-A Literature Review

PURPOSE OF REVIEW

In the interventional treatment of coronary artery disease, new-generation drug-eluting stents (DES) currently are the standard treatment. In addition, drug-coated balloons (DCB) are a well-established option for the treatment of in-stent restenosis in both bare-metal stents (BMS) and DES, where DCBs deliver an antiproliferative drug without the necessity of re-implanting a stent. Since the field of use for DCB has increasingly been extended to other indications such as de novo lesions in small vessel disease (SVD), a review of literature may be useful.

RECENT FINDINGS

Recent randomized trial data show good efficacy and safety for DCB in de novo lesions, especially in small coronary arteries, and confirm long-term clinical efficacy and safety up to three years. DCB are an attractive and safe option in the treatment of de novo lesions in SVD.

Drug-Coated Balloon versus Drug-Eluting Stent in Patients with Small-Vessel Coronary Artery Disease: A Meta-Analysis of Randomized Controlled Trials

Background

Percutaneous coronary intervention (PCI) with drug-eluting stents (DES) of small-vessel coronary artery disease (SVD) is related to an increased risk of in-stent restenosis (ISR) and stent thrombosis (ST). The application of the drug-coated balloon (DCB) for patients with SVD remains controversial.

Objectives

Assess the outcomes of DCB in the treatment of SVD compared with DES in patients with SVD.

Methods

A meta-analysis of randomized controlled trials (RCTs) published up to June 2020, reporting the outcomes of DCB versus DES in the treatment of SVD, was performed.

Results

Four RCTs with 1227 patients were included. The results indicated that DCB was associated with the decreased risk for myocardial infarction (MI) compared with the DES, but the difference showed no significance (OR 0.50, 95% CI 0.24-1.03, P=0.06). And, there was no significant difference in death (OR 0.76, 95% CI 0.17-3.43, P=0.72), cardiac death (OR 1.92, 95% CI 0.74-4.98, P=0.18), target vessel revascularization (TVR) (OR 0.81, 95% CI 0.51-1.28, P=0.36), target lesion revascularization (TLR) (OR 1.29, 95% CI 0.66-2.52, P=0.46), and major adverse cardiac events (MACE) (OR 0.92, 95% CI 0.61-1.38, P=0.69) between the DCB group and DES group.

Conclusion

Compared with DES, DCB was associated with a decreased risk of MI among patients with SVD, but the difference showed no significance. The application of DCB in SVD is associated with comparable outcomes of death, TVR, and MACE when compared with DES.

Long-Term Follow-Up of Percutaneous Coronary Intervention With Paclitaxel-Eluting Balloon Catheter

Drug-eluting balloons currently constitute a therapeutic tool used in percutaneous coronary interventions (PCI). Long-term results remain unknown. We evaluated the prognosis of PCI using a second generation paclitaxel-eluting balloon (PEB) in real-world patients. We included all PCI with PEB in de novo or in-stent restenosis coronary lesions performed in our unit from March 2009 to March 2019. We assessed the composite of major adverse cardiovascular events (MACE) rate after a median follow-up of 42 months. Consecutive patients (n = 320) with 386 lesions were included; 46.9% presented with stable angina and 53.1% acute coronary syndromes; 52.6% of the lesions were in-stent restenosis and 47.3% de novo lesions with a mean diameter of 2.4 ± 0.5 mm. A bare metal stent was implanted in 6.7% and a drug-eluting stent in 8.5% of patients. The MACE rate was 8%: 10 (2.6%) cardiovascular deaths, 13 (3.4%) myocardial infarctions, and 16 (4.1%) target lesion revascularization. The all-cause death rate was 5.2%. No cases of thrombosis were recorded. In conclusion, PEB was a safe and effective tool to treat in-stent restenosis and de novo coronary lesions, especially small vessel disease, during long-term follow-up.

Next-Generation Hardware Advances in CT: Cardiac Applications

Impending major hardware advances in cardiac CT include three areas: ultra-high-resolution (UHR) CT, photon-counting CT, and phase-contrast CT. Cardiac CT is a particularly demanding CT application that requires a high degree of temporal resolution, spatial resolution, and soft-tissue contrast in a moving structure. In this review, cardiac CT is used to highlight the strengths of these technical advances. UHR CT improves visualization of calcified and stented vessels but may result in increased noise and radiation exposure. Photon-counting CT uses multiple photon energies to reduce artifacts, improve contrast resolution, and perform material decomposition. Finally, phase-contrast CT uses x-ray refraction properties to improve spatial and soft-tissue contrast. This review describes these hardware advances in CT and their relevance to cardiovascular imaging.

Small vessel coronary artery disease: How small can we go with myocardial revascularization?

The issue of small coronary artery atherosclerosis represents an intriguing aspect of coronary artery disease, which is related with higher rates of peri- and post-procedural complications and impaired long-term outcome. This problem is further complicated by the unclear definition of small coronary vessel. Recent randomized controlled trials have provided new data on possible novel interventional treatment of small coronary vessels with drug-coated balloons instead of traditional new-generation drug-eluting stent implantation. Also, the conservative management represents a therapeutic option in light of the results of the recent ISCHEMIA trial. The current article provides an overview of the most appropriate definition, interventional management, and prognosis of small coronary artery atherosclerosis.

Ultrathin (60 μm), ultralong (≥40 mm) sirolimus-eluting stent: study of clinical and safety profiles among real-world patients

OBJECTIVE

Although thin-strut drug-eluting stents (DES) with a more flexible design are easily obtainable, data regarding using ultralong DES (≥40 mm) for long coronary lesions are limited in the literature. Therefore, the current study assessed the safety and efficacy of an ultralong (≥40 mm) and ultrathin (60 μm) biodegradable polymer-coated sirolimus-eluting stent (SES), Supralimus Grace, with a unique Long Dual Z-link (LDZ-link) design (Sahajanand Medical Technologies Pvt. Ltd., Surat, India) in real-world patients with long coronary lesions.

METHODS

The assigned stents were implanted in 684 patients. The primary endpoint was target lesion failure (TLF), which is a composite of cardiovascular death, target vessel myocardial infarction (MI), and target lesion revascularization (TLR), whereas periprocedural secondary endpoints included device failure (failure of stent delivery, change of stent, and stent fracture) and patient-oriented composite endpoint (POCE), which is a composite of all deaths, any MI, and any revascularization, and stent thrombosis (ST). These outcomes were analyzed at one-year follow-up and during the procedure.

RESULTS

The patients' mean age was 52.7±15.9 years; 537 (78.5%) were males. 626 (91.5%) patients suffered from acute coronary syndrome and 58 (8.5%) patients from chronic coronary syndrome (CSS). 989 lesions were removed. The mean numbers of lesions and stents implanted per patient were 1.3±0.2 mm and 1.4±0.3 mm, respectively. TLF occurred in 42 (6.1%) as a result of cardiac death, target vessel MI, and TLR in 9 (1.3%), 20 (2.9%), and 13 (1.9%) patients, respectively. POCE was observed in 131 patients (19.1%) at one-year follow-up, mainly in 63 (9.2%) patients because of any revascularization. Stent failure was seen in 21 patients (3.1%) as a result of delivery failure (2.2%), edge dissection (0.8%), and fracture (0.1%). Definite and probable ST were observed in 8 (1.1%) and 9 (1.3%) patients, respectively.

CONCLUSION

Ultralong (≥40 mm), ultrathin (60 μm) Supralimus Grace stent can be safely implanted in vessels having long and multiple lesions.

Drug-coated Balloons for Small Coronary Vessel Interventions: A Literature Review

Newer-generation drug-eluting stents (DES) are the standard of care for the treatment of symptomatic coronary artery disease. However, some lack of efficacy has been reported in small coronary arteries based on higher rates of target lesion restenosis, thrombosis and MI resulting in repeated interventions. Drug-coated balloons (DCBs) are an established treatment option for in-stent restenosis in both bare metal stents and DES and they can deliver an anti-proliferative drug into the vessel wall without implanting a stent. DCBs are a promising technique for selected de novo coronary lesions, especially in small vessel disease. In this article, the current evidence for the treatment of small vessel disease with DCBs will be reviewed.

Drug-coated balloons for coronary artery disease: current concepts and controversies

Drug-coated balloons (DCBs) are a novel development for percutaneous coronary intervention. The first successful application was in-stent restenosis but in recent years, strong evidence has been released for its use in native small-vessels disease. Additional applications such as acute myocardial infarction, chronic total occlusion and bifurcation lesions are still under investigation. This article reviews the key studies evaluating the role of DCBs in several settings and reports on interesting cases where DCBs showed positive results for high-risk patients with neoplasm, as well as with high bleeding risk, planned surgery or renal injury. We also highlight a new biodegradable therapy for coronary bifurcation treatment, in which a bioresorbable vascular scaffold is implanted in the main branch, completed with a DCB angioplasty in the side branch when a treatment is deemed necessary.

Drug Coated Balloon-Only Strategy in De Novo Lesions of Large Coronary Vessels

Objectives

We analyzed the efficacy of drug coated balloons (DCB) as a stand-alone-therapy in de novo lesions of large coronary arteries. DCBs seem to be an attractive alternative for the stent-free interventional treatment of de novo coronary artery disease (CAD). However, data regarding a DCB-only approach in de novo CAD are currently limited to vessels of small caliber.

Methods

By means of propensity score (PS) matching 234 individuals with de novo CAD were identified with similar demographic characteristics. This patient population was stratified in a 1:1 fashion according to a reference vessel diameter cut-off of 2.75 mm in small and large vessel disease. The primary endpoint was the rate of clinically driven target lesion revascularization (TLR) at 9 months.

Results

Patients with small vessel disease had an average reference diameter of 2.45 ± 0.23 mm, while the large vessel group averaged 3.16 ± 0.27 mm. Regarding 9-month major adverse cardiac event (MACE), 5.7% of the patients with small and 6.1% of the patients with large vessels had MACE (p=0.903). Analysis of the individual MACE components revealed a TLR rate of 3.8% in small and 1.0% in large vessels (p=0.200). Of note, no thrombotic events in the DCB treated coronary segments occurred in either group during the 9-month follow-up.

Conclusions

Our data demonstrate for the first time that DCB-only PCI of de novo lesions in large coronary arteries (>2.75 mm) is safe and as effective. Interventional treatment for CAD without permanent or temporary scaffolding, demonstrated a similar efficacy for large and small vessels.

Percutaneous Coronary Intervention in the Elderly: Are Drug-coated Balloons the Future?

Background:

Balloon angioplasty revolutionised percutaneous treatment for coronary ar-tery disease four decades ago, but vessel-threatening dissections, elastic recoil and restenosis were major drawbacks to an otherwise successful long-lasting intervention. Subsequent advances with bare metal stents and then drug eluting stents followed, aiming to mitigate the risks of acute vessel closure and restenosis. However, stent implantation often necessitates dual antiplatelet therapy for a pro-longed period of time, which in itself can lead to adverse outcomes, especially in the frail elderly pop-ulation at higher risk of bleeding. More recently, bioabsorbable stents have been implemented in clini-cal practice enabling earlier intimal coverage of the stent and apposition.

However, another addition to the armamentarium of percutaneous coronary intervention is the use of drug-coated balloons without the need for deploying any coronary stents or scaffolds. Drug-coated balloons are semi-compliant balloons coated with an antiproliferative agent that is rapidly released on contact with the vessel intima exerting an anti-restenotic effect. The absence of a metallic scaffold means that the need for antiplatelet therapy can potentially be negated in the longer term if required. In this article, we will review the history of percutaneous coronary intervention and the available evi-dence for the appropriate use of drug-coated balloons especially in the elderly population.

Conclusion:

We will conclude this review by demonstrating the potential use of drug-coated balloon rather percutaneous stenting through case examples.

Drug-coated balloons for de novo lesions in small coronary arteries: rationale and design of BASKET-SMALL 2

The treatment of coronary small vessel disease (SVD) remains an unresolved issue. Drug‐eluting stents (DES) have limited efficacy due to increased rates of instent‐restenosis, mainly caused by late lumen loss. Drug‐coated balloons (DCB) are a promising technique because native vessels remain structurally unchanged. Basel Stent Kosten‐Effektivitäts Trial: Drug‐Coated Balloons vs. Drug‐Eluting Stents in Small Vessel Interventions (BASKET‐SMALL 2) is a multicenter, randomized, controlled, noninferiority trial of DCB vs DES in native SVD for clinical endpoints. Seven hundred fifty‐eight patients with de novo lesions in vessels <3 mm in diameter and an indication for percutaneous coronary intervention such as stable angina pectoris, silent ischemia, or acute coronary syndromes are randomized 1:1 to angioplasty with DCB vs implantation of a DES after successful initial balloon angioplasty. The primary endpoint is the combination of cardiac death, nonfatal myocardial infarction, and target‐vessel revascularization up to 1 year. Secondary endpoints include stent thrombosis, Bleeding Academic Research Consortium (BARC) type 3 to 5 bleeding, and long‐term outcome up to 3 years. Based on clinical endpoints after 1 year, we plan to assess the noninferiority of DCB compared to DES in patients undergoing primary percutaneous coronary intervention for SVD. Results will be available in the second half of 2018. This study will compare DCB and DES regarding long‐term safety and efficacy for the treatment of SVD in a large all‐comer population.

Current concepts on coronary revascularization using BRS in patients with diabetes and small vessels disease

Diabetes mellitus (DM) and small vessel (SV) disease are two major predictors of adverse outcome in patients treated by percutaneous coronary intervention (PCI), even when last generation metallic drug-eluting stents (DES) are used. Bioresorbable scaffold (BRS) technology has been recently developed to overcome the disadvantages of metallic DES due to their permanent struts. Through the resorption process, BRS may provide a vascular restoration that appears very attractive especially when distal or diffusely diseased coronary segments are involved, as in diabetic patients and SV disease. However, robust evidence on the use of BRS in diabetics is lacking, and recent data have raised concerns on the use of BRS in SVs, particularly when reference vessel diameter (RVD) is <2.25 mm. This review aims at summarizing current evidence related to the use of BRS in diabetics and SV disease.

Stent technology in ischemic stroke

Atherosclerotic disease of the cerebral vasculature is a major cause of stroke worldwide. Atherosclerosis that is refractory to best medical management may require revascularization. In these instances, endovascular treatment provides a popular and safe alternative to open surgical techniques. The authors provide an overview of stent technology in the treatment of ischemic stroke, discussing the major studies evaluating stenting for extracranial carotid artery, vertebral artery, and intracranial atherosclerotic disease. The authors describe the commonly used stents with respect to their individual characteristics and technical limitations. Current and future developments in stent technology are also discussed, with areas for further innovation and clinical research.

The outcomes of patients with very small coronary artery disease treated with thin strut cobalt chromium bare metal stents: an observational study

BACKGROUND

Percutaneous coronary interventions (PCI) in coronary artery disease (CAD) with very small vessel diameters remains controversial and challenging. These lesions are usually more diffuse, calcified and tortuous. The usage of thin strut bare metal stents (BMS) with excellent crossing profiles in a very small caliber coronary lesions has increased the likelihood of procedural success.

OBJECTIVES

This observational study assessed the 9-month clinical outcomes in an 'all-comers' population with very small caliber CAD after implantation of thin strut cobalt chromium BMS.

METHODS

Thin strut cobalt chromium BMS implantation in a priori pre-defined subgroups was investigated in a non-randomized, international, multi-center 'all-comers' observational study. Primary end-point was the 9-month clinically driven target lesion revascularization (TLR) rate. Secondary end-points included the 9-month major adverse cardiac event (MACE) and procedural success rates. Data collection was done using an established electronic data acquisition form with built-in plausibility checks.

RESULTS

A total of 783 patients with a mean age of 70.4 ± 12.8 years were enrolled, 205 (26.2 %) of them had vessel diameters of 2.5 mm and smaller which was defined as CAD with very small reference vessel calibers. Older age and diabetics were associated with higher incidences of very small caliber vessels. The mean reference vessel diameter in the very small vessel group was 2.05 ± 0.27 mm and mean diameter for vessels >2.5 mm was 3.41 ± 0.55 mm. Pre-dilatation was performed more often in the very small vessel patients (52.2 vs. 42.2 %; p value 0.007). There was no difference in the overall technical success rates in very small vessel disease group (97.9 vs. 97.7 %). The 9-month TLR rate was 6.3 % for the very small vessels and 3.7 % for vessels >2.5 mm (p = 0.129). The 9-month and in-hospital MACE rates in the very small vessel group and patient with vessel diameters >2.5 mm were not significantly different (13.1 vs. 9.2 %; p = 0.1265 and 5.2 vs. 3.7 %; p = 0.349) respectively.

CONCLUSION

This study has demonstrated that the use of thin strut cobalt chromium BMS in very small vessel CAD was reasonably safe and efficacious in the context of 'real-world' practice.

Small-vessel treatment with contemporary newer-generation drug-eluting coronary stents in all-comers: Insights from 2-year DUTCH PEERS (TWENTE II) randomized trial

BACKGROUND

Treatment of lesions in small vessels was associated with worse clinical outcome, and various definitions of "small vessels" have been used. Data with novel drug-eluting stents are scarce.

METHODS

To compare the outcome of patients with vs without small-vessel treatment, we assessed 2-year follow-up data of the DUTCH PEERS randomized trial (ClinicalTrials.gov: NCT01331707), in which 1,811 all-comers were treated with contemporary zotarolimus-eluting (Resolute Integrity) or everolimus-eluting (Promus Element) stents. Primary end point was target lesion failure (TLF), a composite of cardiac death, target vessel myocardial infarction, and target lesion revascularization.

RESULTS

The rates of TLF (9.5% vs 5.4%; P log rank = .001) and 2 individual components thereof-target vessel myocardial infarction (3.1% vs 1.3%; P log rank = .006) and target lesion revascularization (4.8% vs 2.8%; P log rank = .02)-were higher among 798 (44.1%) patients treated in at least one small vessel (<2.50 mm by quantitative coronary angiography). Multivariate analysis with propensity score adjustment demonstrated that treatment of small-vessel lesions independently predicted TLF at 2-year follow-up (hazard ratio 1.60, 95% CI 1.09-2.34). Patients with the smallest target vessel being <2.25 mm had TLF rates similar to patients with smallest target vessels of 2.25 to <2.50 mm; however, patients treated in vessels no smaller than 2.50 to <3.00 mm and patients treated in vessels ≥3.00 mm had lower TLF rates (9.3%, 9.8%, 5.0%, and 5.8%, respectively; P log rank = .009).

CONCLUSION

Patients treated with novel drug-eluting stents in small-vessel lesions had higher adverse event rates than did patients who had no small-vessel treatment. Our data suggest that with current stents, a vessel diameter <2.50 mm is a suitable threshold to identify small target vessels.

Coronary artery aneurysm following drug-coated balloon treatment

Drug-coated balloons are an effective treatment option for stent restenosis. Because of their potential benefits, the use of drug-coated balloons is predicted to increase in the future and expand further for the treatment of de novo lesions as well. We hereby present a case in which a patient developed a coronary artery aneurysm following the treatment of a de novo native coronary narrowing with a drug-coated balloon.

Composite outcomes in 2.25-mm drug eluting stents: a systematic review

BACKGROUND

Coronary atherosclerosis often involves small-caliber coronaries, yet the safety and efficacy of 2.25-mm DES have been poorly defined, with a general lack of separation of 2.25 with 2.5-mm performance. No randomized head-to-head 2.25 mm DES studies have been reported. There are several single-arm prospective studies, and we aim to systematically review all published specific 2.25-mm data to estimate composite DES-specific performance and highlight current knowledge gaps.

METHODS

We performed a systematic literature search of PubMed, EMBASE, Web of Science and Cochrane database for clinical trials of 2.25-mm DES. Angiographic and composite clinical outcomes were compared with descriptive statistics.

RESULTS

2.25 mm-Paclitaxel (PES), sirolimus (SES), everolimus (EES) and platinum chromium EES DES-specific outcomes have been reported. Death at 12 months for SES, PES, EES and platinum chromium EES was 1.3%, 3.0%, 1.5%, and 4.4%. Rates of target vessel revascularization at 12 months for SES, PES, EES and platinum chromium EES were 5.7%, 13.3%, 8.8%, and 3.3%. Angiographic outcomes at 9 months to one year were as follows: mean late lumen loss (LLL) for SES, PES, and EES was 0.15 ± 0.11-mm, 0.28 ± 0.11-mm, and 0.16 ± 0.41-mm and mean diameter restenosis for SES, PES, and EES were 29.5 ± 6.2%, 34.7 ± 4.2%, and 20.9 ± 22.5%. Reported stent thrombosis rates for 2.25-mm DES were low ranging from 0% to 2.2% in up to 24-months of follow-up.

CONCLUSIONS

This systematic review summarizes and tabulates all available specific data on 2.25-mm DES. Based on our descriptive analysis, 2.25-mm DESs have a favorable safety and efficacy profile for the treatment of very small coronary lesions.

Overaggressive stent expansion without intravascular imaging: impact on restenosis

OBJECTIVE

Aggressive stent expansion is required for optimal strut apposition, but risk of stent deformation, fracture and subsequent restenosis is potentially greater when performed without intravascular imaging guidance. We investigated how frequently stents are 'overexpanded' and whether this correlates with restenosis.

DESIGN AND SETTING

Single-centre prospective database study at a high-volume tertiary university hospital.

PATIENTS

243 patients undergoing single-vessel stenting for de novo stenosis in 277 lesions. Exclusion criteria were bifurcational, graft or left main disease and intravascular imaging use. All had ischaemia-driven repeat coronary angiography up to 48 months later. Degree of stent overexpansion was the difference between nominal and final stent size.

RESULTS

Stents were expanded above nominal in 99% of cases and above rated burst pressure in 52%. Stents were expanded >20% above nominal in 12% of cases. Stents overexpanded by >20% were smaller (2.87 vs 3.19 mm), longer (24 vs 19 mm) and more often drug-eluting (53% vs 27%). Angiographic restenosis was observed in 80 lesions (29%). There was no correlation between degree of overexpansion and per cent angiographic restenosis across the whole group (R(2)=-0.01; p=0.09), in those with stent overexpansion >20% (p=0.31) or small stents <3 mm (p=0.71). Indeed, in the group with stent overexpansion >25%, the greater the overexpansion, the less the per cent angiographic restenosis (p=0.02).

CONCLUSIONS

In this real-world population undergoing non-complex percutaneous coronary intervention without intravascular imaging, any tendency to overaggressive stent expansion did not predispose at all to restenosis.

Intracoronary optical coherence tomography and histology of overlapping everolimus-eluting bioresorbable vascular scaffolds in a porcine coronary artery model: the potential implications for clinical practice

OBJECTIVES

This study sought to assess the vascular response of overlapping Absorb stents compared with overlapping newer-generation everolimus-eluting metallic platform stents (Xience V [XV]) in a porcine coronary artery model.

BACKGROUND

The everolimus-eluting bioresorbable vascular scaffold (Absorb) is a novel approach to treating coronary lesions. A persistent inflammatory response, fibrin deposition, and delayed endothelialization have been reported with overlapping first-generation drug-eluting stents.

METHODS

Forty-one overlapping Absorb and overlapping Xience V (XV) devices (3.0 × 12 mm) were implanted in the main coronary arteries of 17 nonatherosclerotic pigs with 10% overstretch. Implanted coronary arteries were evaluated by optical coherence tomography (OCT) at 28 days (Absorb n = 11, XV n = 7) and 90 days (Absorb n = 11, XV n = 8), with immediate histological evaluation following euthanasia at the same time points. One animal from each time point was evaluated with scanning electron microscopy alone. A total of 1,407 cross sections were analyzed by OCT and 148 cross sections analyzed histologically.

RESULTS

At 28 days in the overlap, OCT analyses indicated 80.1% of Absorb struts and 99.4% of XV struts to be covered (p < 0.0001), corresponding to histological observations of struts with cellular coverage of 75.4% and 99.6%, respectively (p < 0.001). Uncovered struts were almost exclusively related to the presence of "stacked" Absorb struts, that is, with a direct overlay configuration. At 90 days, overlapping Absorb and overlapping XV struts demonstrated >99% strut coverage by OCT and histology, with no evidence of a significant inflammatory process, and comparable % volume obstructions.

CONCLUSIONS

In porcine coronary arteries implanted with overlapping Absorb or overlapping XV struts, strut coverage is delayed at 28 days in overlapping Absorb, dependent on the overlay configuration of the thicker Absorb struts. At 90 days, both overlapping Absorb and overlapping XV have comparable strut coverage. The implications of increased strut thickness may have important clinical and design considerations for bioresorbable platforms.

Post-marketing surveillance in the published medical and grey literature for percutaneous transluminal coronary angioplasty catheters: a systematic review

BACKGROUND

Post-marketing surveillance (PMS) may identify rare serious incidents or adverse events due to the long-term use of a medical device, which was not captured in the pre-market process. Percutaneous transluminal coronary angioplasty (PTCA) is a non-surgical procedure that uses a balloon-tipped catheter to enlarge a narrowed artery. In 2011, 1,942 adverse event reports related to the use of PTCA catheters were submitted to the FDA by the manufacturers, an increase from the 883 reported in 2008. The primary research objective is to conduct a systematic review of the published and grey literature published between 2007 and 2012 for the frequency of incidents, adverse events and malfunctions associated with the use of PTCA catheters in patients with coronary artery disease (CAD). Grey literature has not been commercially published.

METHODS

We searched MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials and PubMed for medical literature on PMS for PTCA catheters in patients with CAD published between January 2007 and July 2012. We also searched the grey literature.

RESULTS

This review included 11 studies. The in-hospital adverse events reported were individual cases of myocardial infarction and hematoma. In studies of patients with coronary perforation, more patients with balloon angioplasty were identified compared with patients who required stenting.

CONCLUSIONS

Our systematic review illustrates that the volume and quality of PMS studies associated with the use of PTCA catheters in patients with CAD are low in the published and grey literature, and may not be useful sources of information for decisions on safety. In most studies, the objectives were not to monitor the long-term safety of the use of PTCA catheters in clinical practice. Future studies can explore the strengths and limitations of PMS databases administered by regulatory authorities.

Percutaneous revascularization strategies in small-vessel disease

Percutaneous coronary intervention (PCI) of small coronary vessels represents a real challenge for myocardial revascularization because of the high risk of stent-restenosis and increased risk of adverse clinical events. Moreover, small coronary arteries supply small myocardial territories therefore questioning the clinical significance of small-vessel stenoses. The definition of small-vessel disease and PCI-strategies used are very heterogeneous across studies. The present review will focus on percutaneous coronary revascularization in patients with small vessel coronary artery disease.

Compliance charts to guide non-complex small artery stenting: validation by quantitative coronary angiography

OBJECTIVE

To determine whether stent sizing derived from manufacturers' compliance charts provides a reasonable in vivo estimate of final minimum lumen diameter (MLD) when compared with quantitative coronary angiography (QCA).

DESIGN

Single-centre measurement comparison study.

SETTING

Tertiary referral university hospital.

PATIENTS

Fifty cases receiving a single stent for non-complex de novo stenosis were randomly selected from the percutaneous coronary intervention database of our high-volume centre. Restenosis, stent thrombosis, bifurcational disease, rotablation, left main or graft stenting, intravascular ultrasound or kissing balloon inflations were exclusion criteria.

MAIN OUTCOME MEASURES

Equality and limits of agreement (LOA) between compliance chart and QCA measurements of final MLD, especially focusing on patients with small stents<3 mm. The paired t test and Bland-Altman plots were used to compare measurements.

RESULTS

There was no significant difference between compliance chart-derived and QCA final MLD (n=50; mean -0.034 mm, SD 0.35, 95% CI -0.132 to +0.064; p=0.49), with reasonable Bland-Altman LOA between the two methods of assessing final MLD in the overall group (LOA -0.72 to +0.66 mm), as well as in the group of particular interest with Derived final MLD <3 mm (n=30; mean 0.019 mm, SD 0.27, 95% CI -0.082 to +0.119; p=0.71; LOA -0.52 to +0.56 mm).

CONCLUSIONS

Compliance charts provide an acceptable estimate of final MLD and are a reasonable guide to sizing during non-complex stenting, especially in small vessels <3 mm.

[Interventional angioradiology as a solution for microsurgical flap failure]

The microsurgical failure rate is almost constant for several decades. We present two case reports describing a novel method of free flap salvage using angioradiological techniques. Our first case shows the potential utility of in situ thrombolysis, our second case describes the first use of stents within a microsurgical anastomosis. In boths cases, the flap would have been lost immediately, because flap revisions failed. Thus, before abandoning on a flap, one could perform a simple angiography to evaluate further angioradiological salvage possibilities and hereby contribute to improve long term microsurgical failure rate.