Impact of intravascular ultrasound-guided minimum-contrast coronary intervention on 1-year clinical outcomes in patients with stage 4 or 5 advanced chronic kidney disease

Outcomes of ultra-low contrast percutaneous coronary intervention in patients with advanced chronic kidney disease

BACKGROUND

Coronary angiography and percutaneous coronary intervention (PCI) in patients with chronic kidney disease (CKD) is associated with increased risk of contrast induced nephropathy (CIN) and requirement for renal replacement therapy (RRT).

OBJECTIVES

We aimed to evaluate our single center experience of ultra-low contrast PCI in patients with CKD and to characterize 1 year outcomes.

METHODS

We performed a retrospective analysis of ultra-low contrast PCI at our institution between 2016 and 2022. Patients with CKD3b-5 (eGFR <45 mL/min/1.73m2), not on RRT who underwent ultra-low contrast PCI ( < 30 mL of contrast during PCI) were included. Primary outcomes included change in eGFR post-procedurally, and death, RRT requirement, and major adverse cardiac events (MACE) at 1 year follow-up.

RESULTS

One hundred patients were included in the study. The median age was 67 years old and 28% were female. The median baseline eGFR was 21.5 mL/min/1.73m2 (IQR 14.08-32.0 mL/min/1.73m2). A median of 8.0 mL (IQR 0-15 mL) of contrast was used during PCI. Median contrast use to eGFR ratio was 0.37 (IQR 0-0.59). There was no significant difference between pre-and postprocedure eGFR (p = 0.84). At 1 year, 8% of patients died, 11% required RRT and 33% experienced MACE. The average time of RRT initiation was 7 months post-PCI. Forty-four patients were undergoing renal transplant evaluation, of which 17 (39%) received a transplant.

CONCLUSIONS

In patients with advanced CKD, ultra-low contrast PCI is feasible and safe with minimal need for peri-procedural RRT. Moreover, ultra-low contrast PCI may allow for preservation of renal function in anticipation of renal transplantation.

Global Consensus Recommendations on Improving the Safety of Chronic Total Occlusion Interventions

Safety is of critical importance to chronic total occlusion (CTO) percutaneous coronary intervention (PCI). This global consensus statement provides guidance on how to optimise the safety of CTO) PCI, addressing the following 12 areas: 1. Set-up for safe CTO PCI; 2. Guide catheter--associated vessel injuries; 3. Hydraulic dissection, extraplaque haematoma expansion, and aortic dissections; 4. Haemodynamic collapse during CTO PCI; 5. Side branch occlusion; 6. Perforations; 7. Equipment entrapment; 8. Vascular access considerations; 9. Contrast-induced acute kidney injury; 10. Radiation injury; 11 When to stop; and, 12. Proctorship. This statement complements the global CTO crossing algorithm; by advising how to prevent and deal with complications, this statement aims to facilitate clinical practice, research, and education relating to CTO PCI.

Intravascular Imaging in the Diagnosis and Management of Patients With Suspected Intracoronary Pathologies: A CJC White Paper

Intravascular imaging has become an integral part of the diagnostic and management strategies for intracoronary pathologies. In this White Paper we summarize current evidence and its implications on the use of intravascular imaging in interventional cardiology practice. The areas addressed are planning and optimization of percutaneous coronary intervention, management of stent failure, and evaluation of ambiguous coronary lesions and myocardial infarction with nonobstructive coronary disease. The findings presented followed the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system in an expert consensus process that involved a diverse writing group vetted by a review group. Expert consensus was achieved around 9 statements. Use of intravascular imaging in guiding percutaneous revascularization is supported by high-quality evidence, particularly for lesions with increased risk of recurrent events or stent failure. Specific considerations for intravascular imaging guidance of intervention in left main lesions, chronic occlusion lesions, and in patients at high risk of contrast nephropathy are explored. Use of intravascular imaging to identify pathologies associated with stent failure and guide repeat intervention, resolve ambiguities in lesion assessment, and establish diagnoses in patients who present with myocardial infarction with nonobstructive coronary disease is supported by moderate- to low-quality evidence. Each topic is accompanied by clinical pointers to aid the practicing interventional cardiologist in implementation of the White Paper findings. The findings presented in this White Paper will help to guide the use of intravascular imaging toward situations in which the balance of efficacy, safety, and cost are most optimal.

Absolute zero-contrast percutaneous coronary interventions: An intravascular ultrasound-guided case series and literature review

PURPOSE

Contrast media (CM)-associated adverse effects including mainly acute kidney injury and hypersensitivity reactions still remain a significant treatment burden to vulnerable patients requiring percutaneous coronary intervention (PCI). The complete omission of CM administration accompanied by intravascular ultrasound (IVUS) guidance may offer an appropriate revascularization treatment.

METHODS

We hereby present a case series of four patients with challenging coronary lesions and relative/absolute contraindications to CM use [(hypersensitivity reaction owning to CM, history of contrast-induced acute kidney injury, solitary kidney, or advanced chronic kidney disease (CKD)] who underwent absolute zero-contrast IVUS-guided PCI following a predetermined protocol.

RESULTS

The initial diagnostic angiography was reviewed for landmark identification, and multiple guidewires created a metallic road map providing additional landmarks and protected side branches. IVUS imaging was performed to determine lesion length, reference segments and landing zones, assess stent expansion/apposition and identify major complications. All procedures were successfully completed without any CM administration, renal function deterioration, pericardial effusion, or stent edge dissection.

CONCLUSIONS

We demonstrated the feasibility of absolute zero-contrast IVUS-guided PCI in patients with complex coronary lesions susceptible to CM-associated adverse effects. Since the safety of this strategy is well-documented in patients with CKD and challenging lesions morphology even in acute settings, evidence-based validation of this approach is capable of changing the otherwise conservative treatment of vulnerable patients where even minimum doses of CM may have detrimental effects.

SUMMARY FOR THE ANNOTATED TABLE OF CONTENTS

Patients with vulnerable renal function as well as former hypersensitivity reaction to contrast media encounter a significant treatment burden regarding coronary artery disease. Zero-contrast IVUS-guided strategy based on a predetermined protocol provides a feasible alternative approach in patients susceptible to contrast media-associated adverse effects even in the presence of complex coronary lesions.

Acute Kidney Injury After Percutaneous Coronary Intervention Guided by Intravascular Ultrasound

Purpose We investigated the impact of intravascular ultrasound guidance on reducing the incidence of contrast-induced acute kidney injury (CI-AKI) in patients undergoing percutaneous coronary intervention (PCI). Methods Ninety-nine patients were enrolled in this prospective cohort who were not randomly assigned to angiography-guided percutaneous coronary intervention or intravascular ultrasound-guided percutaneous coronary intervention. The patients were hospitalized at the Vietnam National Heart Institute - Bach Mai Hospital between 2019 and 2020. Acute kidney injury incidence during hospitalization was the primary endpoint. Results A total of 99 patients were divided into two groups: the intravascular ultrasound-guided group (33 participants) and the angiography-guided group (66 participants). The mean ± SD contrast volume of each group was 95.2 ± 37.1 mL and 133.0 ± 36.0 mL for the ultrasound-guided and angiography-guided groups, with P < 0.0001. Intravascular imaging-guided percutaneous coronary intervention (IVUS-guided PCI) was associated with reduced acute kidney injury incidence during hospitalization: 0.0% vs. 12.12% and P = 0.049. Conclusions Intravascular ultrasound is a safe imaging tool that guides percutaneous coronary intervention and significantly reduces the rate of acute kidney injury compared to angiography alone. Patients who have a high chance of experiencing acute kidney injury benefit from using intravascular ultrasound.

Role of intravascular ultrasound and optical coherence tomography in intracoronary imaging for coronary artery disease: a systematic review

Coronary angiography has long been the standard for coronary imaging, but it has limitations in assessing vessel wall anatomy and guiding percutaneous coronary intervention (PCI). Intracoronary imaging techniques like intravascular ultrasound (IVUS) and optical coherence tomography (OCT) can overcome these limitations. IVUS uses ultrasound and OCT uses near-infrared light to visualize coronary pathology in unique ways due to differences in temporal and spatial resolution. These techniques have evolved to offer clinical utility in plaque characterization and vessel assessment during PCI. Meta-analyses and adjusted observational studies suggest that both IVUS and OCT-guided PCI correlate with reduced cardiovascular risks compared to angiographic guidance alone. While IVUS demonstrates consistent clinical outcome benefits, OCT evidence is less robust. IVUS has progressed from early motion detection to high-resolution systems, with smaller compatible catheters. OCT utilizes near infrared light to achieve unparalleled resolutions, but requires temporary blood clearance for optimal imaging. Enhanced visualization and guidance make IVUS and OCT well-suited for higher risk PCI in patients with diabetes and chronic kidney disease by allowing detailed visualization of complex lesions and ensuring optimal stent deployment and positioning in PCI for patients with type 2 diabetes and chronic kidney disease, improving outcomes. IVUS and recent advancements in zero- and low-contrast OCT techniques can reduce nephrotoxic contrast exposure, thus helping to minimize PCI complications in these high-risk patient groups. IVUS and OCT provide valuable insights into coronary pathophysiology and guide interventions precisely compared to angiography alone. Both have comparable clinical outcomes, emphasizing the need for tailored imaging choices based on clinical scenarios. Continued refinement and integration of intravascular imaging will likely play a pivotal role in optimizing coronary interventions and outcomes. This systematic review aims to delve into the nuances of IVUS and OCT, highlighting their strengths and limitations as PCI adjuncts.

Carbon dioxide angiography during peripheral vascular interventions is associated with decreased cardiac and renal complications in patients with chronic kidney disease

OBJECTIVE

Patients with chronic kidney disease (CKD) who undergo peripheral vascular interventions (PVI) with iodinated contrast are at higher risk of post-contrast acute kidney injury (PC-AKI). Carbon dioxide (CO2) angiography can reduce iodinated contrast volume usage in this patient population, but its impact on PC-AKI has not been studied. We hypothesize that CO2 angiography is associated with a decrease in PC-AKI in patients with advanced CKD.

METHODS

The Vascular Quality Initiative PVI dataset from 2010 to 2021 was reviewed. Only patients with advanced CKD (estimated glomular filtration rate <45 ml/min/1.73 m2) treated for peripheral arterial disease were included. Propensity matching and multivariate logistic regression based on demographics, comorbidities, CKD stage, and indications were used to compare the outcomes of patients treated with and without CO2.

RESULTS

There were 20,706 PVIs performed in patients with advanced CKD, and only 22% utilized CO2 angiography. Compared with patients treated without CO2, patients who underwent CO2 angiography were younger and less likely to be women or White, and more likely to have poor renal function, diabetes, cardiac comorbidities, and present with tissue loss. Propensity matching yielded well-matched groups with 4472 patients in each group. The procedural details after matching demonstrated 50% reduction in the volume of contrast used (32±33 vs 65±48 mL; P < .01). PVI with CO2 angiography was associated with lower rates of PC-AKI (3.9% vs 4.8%; P = .03) and cardiac complications (2.1% vs 2.9%; P = .03) without a significant difference in technical failure or major/minor amputations. Low contrast volumes (≤50 mL for CKD3, ≤20 mL for CKD4, and ≤9 mL for CKD5) are associated with reduced risk of PC-AKI (hazard ratio, 0.59; P < .01).

CONCLUSIONS

CO2 angiography reduces iodinated contrast volume usage during PVI and is associated with decreased cardiac complications and PC-AKI. CO2 angiography is underutilized and should be considered for patients with advanced CKD who require endovascular therapy.

Procedural and Technological Innovations Facilitating Ultra-low Contrast Percutaneous Coronary Interventions

Ultra-low-dose contrast percutaneous coronary intervention (PCI) is a valuable approach in selected complex high-risk patients with renal failure. One of the objectives of ultra-low contrast PCI is to decrease the probability of developing postprocedural contrast-induced nephropathy (CIN), which predominately affects patients with baseline renal dysfunction. CIN is associated with poor clinical outcomes and increased healthcare-related costs. Another two clinical scenarios in which reduced dependence on contrast administration by the operator may contribute to improved safety are PCI in complex, high-risk indicated patients and in shock. In this review, we discuss the procedural techniques and recent technological innovations that enable ultra-low-dose contrast PCI to be performed in the cardiac cath lab.

Utilization Rate and Outcomes of Intravascular Imaging in Elderly Patients Presenting With ST-Elevation Myocardial Infarction

BACKGROUND

Elderly patients presenting with ST-elevation myocardial infarction (STEMI) represent a vulnerable population with comorbid conditions and complex coronary anatomy. We aimed to describe the utilization rate and outcomes of intravascular imaging to guide percutaneous coronary intervention (PCI) in this population.

METHODS

The Nationwide Readmissions Database was queried for all hospitalizations for STEMI involving PCI from 2018 to 2019. Hospitalizations were stratified by patient age into a younger cohort <75 years (mean age 58.7 ± 9.5 years) and an older cohort ≥75 years. Propensity score-weighed regression analysis was used to identify the association of intravascular imaging with in-hospital mortality, 90-day all-cause readmission, and readmission for myocardial infarction (MI).

RESULTS

A total of 299,619 STEMI PCI hospitalizations were included. Intravascular imaging was utilized less frequently in the older cohort (6.8 % vs 7.8 %, odds ratio [OR] 0.87, 95 % CI 0.82-0.92, p < 0.001). In both cohorts, intravascular imaging was more likely to be used with anterior STEMI, complex PCI, mechanical support, and thrombectomy. Propensity score analysis showed the use of intravascular imaging was associated with lower in-hospital mortality in both cohorts (OR 0.60, 95 % CI 0.52-0.68, p < 0.001 in the younger cohort and OR 0.61, 95 % CI 0.51-0.72, p < 0.001 in the older cohort). There was no difference in 90-day all-cause readmission or readmission for MI with intravascular imaging.

CONCLUSIONS

Intravascular imaging during STEMI PCI is associated with lower in-hospital mortality regardless of age. Further studies are needed to understand the low utilization rates especially among elderly patients.

Impact of intravascular ultrasound in acute myocardial infarction patients at high ischemic risk

INTRODUCTION AND OBJECTIVES

Evidence for the role of intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) in patients at high ischemic risk of acute myocardial infarction (AMI) is lacking. This study aimed to investigate the long-term clinical impact of IVUS-guided PCI in patients at high ischemic risk of AMI.

METHODS

Among 13 104 patients with AMI enrolled in the Korea Acute Myocardial Infarction Registry-National Institutes of Health, we selected 8890 patients who underwent successful PCI with second-generation drug-eluting stent implantation and classified them into 2 groups based on whether or not they were at high ischemic risk or not, defined as any of the following: number of stents implanted ≥ 3, 3 vessels treated, ≥ 3 lesions treated, total stent length> 60mm, left main PCI, diabetes mellitus, and chronic kidney disease. The primary outcome was target lesion failure including cardiac death, target vessel myocardial infarction, and ischemia-driven target lesion revascularization at 3 years.

RESULTS

In 4070 AMI patients at high ischemic risk, IVUS-guided PCI (21.6%) was associated with a significantly lower risk of target lesion failure at 3 years (6.7% vs 12.0%; HR, 0.54; 95%CI, 0.41-0.72; P <.001) than angiography-guided PCI. The results were consistent after confounder adjustment, inversed probability weighting, and propensity score matching.

CONCLUSIONS

In patients at high ischemic risk of AMI who underwent PCI with second-generation drug-eluting stent implantation, use of IVUS guidance was associated with a significant reduction in 3-year target lesion failure. iCreaT study No. C110016.

Prevention of Contrast-Induced Nephropathy After Cardiovascular Catheterization and Intervention With High-Dose Strong Statin Therapy in Japan - The PREVENT CINC-J Study

BACKGROUND

Previous studies have reported that high-dose strong statin therapy reduces the incidence of contrast-induced nephropathy (CIN) in statin naïve patients; however, the efficacy of high-dose strong statins for preventing CIN in real-world clinical practice remains unclear. The aim of this study was to evaluate the efficacy of strong statin therapy in addition to fluid hydration for preventing CIN after cardiovascular catheterization.

METHODS AND RESULTS

This prospective, multicenter, randomized controlled trial included 420 patients with chronic kidney disease who underwent cardiovascular catheterization. They were assigned to receive high-dose pitavastatin (4 mg/day × 4 days) on the day before and of the procedure and 2 days after the procedure (Statin group, n=213) or no pitavastatin (Control group, n=207). Isotonic saline hydration combined with a single bolus of sodium bicarbonate (20 mEq) was scheduled for administration to all patients. In the control group, statin therapy was continued at the same dose as that before randomization. CIN was defined as a ≥0.5 mg/dL increase in serum creatinine or ≥25% above baseline at 48 h after contrast exposure. Before randomization, 83% of study participants were receiving statin treatment. The statin group had a higher incidence of CIN than the control group (3.0% vs. 0%, P=0.01). The 12-month rate of major adverse cardiovascular events was similar between the 2 groups.

CONCLUSIONS

High-dose pitavastatin increases the incidence of CIN in this study population.

The Principles of Ultra-Low Contrast Percutaneous Coronary Intervention

Ultra-low contrast percutaneous coronary intervention (ULCPCI) can be performed electively in advanced chronic kidney disease. Engage guide catheter and advance guidewire into the coronary artery without using contrast. IVUS-guided PCI can reduce the contrast load. Perform co-registration of distal and proximal radio-opaque marker bands of intravascular ultrasound (IVUS) catheter. Deploy the stent at the target lesion under fluoroscopic guidance of these co-registered position of the IVUS-marking images. Complete the ULCPCI procedure with a final angiography using minimal contrast. Newer contrast sparing techniques and intravascular imaging technologies provide opportunities to perform ULCPCI efficiently with good results and the least complications.

Effect of Procedural Volume on In-Hospital Outcomes After Percutaneous Coronary Intervention in Patients With Chronic Kidney Disease (from the Japanese National Clinical Data [J-PCI Registry])

Chronic kidney disease (CKD) increases the risk of death and other poor outcomes in patients with cardiovascular diseases. This study investigated the relation between the institutional CKD percutaneous coronary intervention (PCI) volume and in-hospital clinical outcomes in patients with CKD. Among 1,199,901 patients who underwent PCI in 2014 to 2018 from the Japanese nationwide registry, we analyzed 220,509 patients with CKD. Patients were classified into quartiles (Q) according to the mean annual institutional CKD-PCI volume (Q1 <42 PCIs/year, Q2 <74 PCIs/year, Q3 <124 PCIs/year, Q4 ≥125 PCIs/year). The primary outcome was a composite of in-hospital death and periprocedural complications. The mean age of patients was 73 ± 10 years, and 36% (n = 78,332) were on dialysis. PCI was more likely to be performed with rotational atherectomy devices in high-volume institutions. Contrast volume was lower, the rate of radial access PCI was higher, and door-to-balloon time (for ST-elevation myocardial infarction) was shorter in the highest quartile institutions. Primary outcomes were observed in 6,539 patients (3.0%). The crude rate of the primary outcome was lowest in institutions with the highest PCI volume (Q1 3.4%, Q2 3.0%, Q3 3.0%, Q4 2.4%, p <0.001); higher PCI volume was associated with reduced frequency of the primary outcome (odds ratio [95% confidence interval] relative to Q1:Q2, 0.89 [0.83 to 0.96]; Q3 0.90 [0.84 to 0.97]; and Q4 0.76 [0.84 to 0.97]). In conclusion, the procedural characteristics and outcomes of PCI differed significantly by institutional volume in patients with CKD. When considering revascularization among these patients, institutional CKD-PCI volume needs to be incorporated in decision-making.

Machine learning prediction model of acute kidney injury after percutaneous coronary intervention

Acute kidney injury (AKI) after percutaneous coronary intervention (PCI) is associated with a significant risk of morbidity and mortality. The traditional risk model provided by the National Cardiovascular Data Registry (NCDR) is useful for predicting the preprocedural risk of AKI, although the scoring system requires a number of clinical contents. We sought to examine whether machine learning (ML) techniques could predict AKI with fewer NCDR-AKI risk model variables within a comparable PCI database in Japan. We evaluated 19,222 consecutive patients undergoing PCI between 2008 and 2019 in a Japanese multicenter registry. AKI was defined as an absolute or a relative increase in serum creatinine of 0.3 mg/dL or 50%. The data were split into training (N = 16,644; 2008-2017) and testing datasets (N = 2578; 2017-2019). The area under the curve (AUC) was calculated using the light gradient boosting model (GBM) with selected variables by Lasso and SHapley Additive exPlanations (SHAP) methods among 12 traditional variables, excluding the use of an intra-aortic balloon pump, since its use was considered operator-dependent. The incidence of AKI was 9.4% in the cohort. Lasso and SHAP methods demonstrated that seven variables (age, eGFR, preprocedural hemoglobin, ST-elevation myocardial infarction, non-ST-elevation myocardial infarction/unstable angina, heart failure symptoms, and cardiogenic shock) were pertinent. AUC calculated by the light GBM with seven variables had a performance similar to that of the conventional logistic regression prediction model that included 12 variables (light GBM, AUC [training/testing datasets]: 0.779/0.772; logistic regression, AUC [training/testing datasets]: 0.797/0.755). The AKI risk model after PCI using ML enabled adequate risk quantification with fewer variables. ML techniques may aid in enhancing the international use of validated risk models.

Ultra-low contrast, complex left main coronary intervention case series using novel intravascular ultrasound technology

Background

Contrast-induced nephropathy (CIN) in patients with chronic kidney disease (CKD) carries a high morbidity and mortality. Ultra-low contrast percutaneous coronary intervention (ULPCI) has previously been described. Complex left main (LM) ULPCI using two-stent strategy guided by novel intravascular ultrasound (IVUS) co-registration software has not been described. We report a series of complex LM ULPCI using IVUS co-registration.

Case Summaries

Five patients with estimated glomerular filtration rate ≤20 mL/min who presented with stable angina or non-ST segment elevation acute coronary syndrome underwent percutaneous coronary intervention (PCI). The patients previously had diagnostic angiography performed as a separate procedure. Successful LM ULPCI was performed in all patients with a provisional and two-stent bifurcation strategies. These were complex procedures, some of which required haemodynamic support and rotational atherectomy.

Discussion

This report describes the first ULPCI using a dedicated two-stent LM bifurcation strategy and using rotational atherectomy and IVUS co-registration. This technology facilitated complex PCI in this high-risk patient group with minimal contrast use (≤6 mL) with optimal results and no patients developed acute kidney injury after intervention. The adaptation of ULPCI to daily practice in patients at risk of CIN will improve treatment for this underserved patient group.

Safety and Efficacy of Minimum- or Zero-Contrast IVUS-Guided Percutaneous Coronary Interventions in Chronic Kidney Disease Patients: A Systematic Review

Conventional percutaneous coronary interventions (PCIs) frequently cause severe complications in chronic kidney disease (CKD) patients. Low-to-zero contrast intravascular ultrasound (IVUS) guided PCIs are promising alternatives in the CKD setting. We aim to systematically review up-to-date literature that have reported data and outcomes of low-to-zero contrast PCIs performed in CKD patients. We searched Embase, PubMed, and Cochrane databases for full-text articles that reported original data regarding efficacy and/or safety outcomes of IVUS-guided PCIs in patients with CKD. The quality of non-randomized trials included was assessed using the Newcastle-Ottawa scale. Six papers were included in the present systematic review: One non-randomized trial, two case series, and three case reports. Given the literature reported so far, contrast-free and IVUS-guided PCI procedures in patients with CKD appear to be safe (both in cardiac and renal outcomes) with a comparable efficacy to the conventional procedure, even in complex atherosclerotic lesions. No patient included in the mentioned studies showed renal function deterioration and did not need renal replacement therapy after the zero-contrast IVUS-guided percutaneous procedures. From a cardiovascular point of view, this technique proved to be safe in terms of cardiovascular outcomes. The undesirable consequences of conventional PCI in the CKD population might soon be effectively hampered by safer low-to-zero contrast IVUS-guided PCI procedures after a mandatory and rigorous evidence-based validation in long-awaited randomized controlled trials.

Impact of clinical presentations on lipid core plaque assessed by near-infrared spectroscopy intravascular ultrasound

Near-infrared spectroscopy-intravascular ultrasound (NIRS-IVUS) studies have demonstrated that lipid core plaque (LCP) is frequently observed in the culprit segment of myocardial infarction (MI). However, little is known about the impact of clinical presentations such as chronic coronary syndrome (CCS) and acute coronary syndrome (ACS) including unstable angina (UA), non ST-segment elevation MI (NSTEMI), and ST-segment elevation MI (STEMI) on LCP. The present prospective single-center registry included a total of 178 patients who underwent percutaneous coronary intervention under NIRS-IVUS guidance. Patients were divided into CCS and ACS groups, and ACS patients were further sub-divided into the 3 groups according to the clinical presentation. The primary endpoint was coronary LCP in the target lesion assessed by NIRS-IVUS with maximal lipid core burden index over any 4 mm segment (maxLCBI_4mm). The study population included 124 and 54 patients with CCS and ACS. MaxLCBI_4mm in the target lesion was significantly higher in the ACS group than in the CCS group (503 [284-672] vs. 406 [250-557], p = 0.046). Among ACS patients, MaxLCBI_4mm in the target lesion was also significantly different in those with UA (n = 18), NSTEMI (n = 21), and STEMI (n = 15) (288 [162-524] vs. 518 [358-745] vs. 646 [394-848], p = 0.021). In conclusion, LCP assessed by NIRS-IVUS, a surrogate of coronary plaque vulnerability, was significantly different according to the clinical presentations such as CCS, UA, NSTEMI, and STEMI.

Zero-contrast percutaneous coronary intervention for chronic total occlusions guided by intravascular ultrasound with ChromaFlo mode: a case report

Background

Contrast agent allergy may result in severe adverse events that prevent the use of percutaneous coronary intervention (PCI) in some patients, especially for those with complex lesions.

Case summary

We describe a 59-year-old man who presented with the multi-vessel disease and suffered from contrast allergy. The patient refused to have coronary artery bypass grafting surgery, thus two-stage PCI procedures without iodinated contrast media were performed after a detailed discussion with the heart team, including a chronic total occlusion (CTO) lesion in the proximal left anterior descending artery. The intravascular ultrasound (IVUS) was used for finding the entry point of the proximal fibre cap, and assessing the lesion, thereby marking the positions of the proximal and distal edges of the stent. After PCI, stent expansion and subtle edge dissection or incomplete apposition were confirmed by IVUS and ChromaFlo imaging. Zero-contrast PCI was done successfully without any complication.

Discussion

This case report illustrates the feasibility and safety of performing CTO-PCI without contrast agent in carefully and well prepared selected patients.

Long-term renal outcomes after elective percutaneous coronary intervention in patients with advanced renal dysfunction

The aim of the present study was to evaluate the renal outcomes, including the time course of renal function, after elective PCI in patients with advanced renal dysfunction and to assess the predictors of renal dysfunction progression. This is a subanalysis of a previous observational multicenter study that investigated long-term clinical outcomes in patients with advanced renal dysfunction (eGFR < 30 mL/min/1.73 m²), focusing on 151 patients who underwent elective PCI and their long-term renal outcomes. Renal dysfunction progression was defined as a 20% relative decrease in eGFR at 1 year from baseline or the initiation of permanent dialysis within 1 year. Progression of renal dysfunction at 1 year occurred in 42 patients (34.1%). Among patients with renal dysfunction progression, the decrease of renal function from baseline was not observed at 1 month but after 6 months of the index PCI. Baseline eGFR and serum albumin level were significant predictors of renal dysfunction progression at 1 year. Among 111 patients who had not been initiated on dialysis within 1 year, those with renal dysfunction progression had a significantly higher incidence of dialysis initiation more than 1 year after the index PCI than those with preserved renal function (p < 0.001). Among patients with advanced renal dysfunction who underwent elective PCI, 34.1% showed renal dysfunction progression at 1 year. The decrease in renal function was not observed at 1 month but after 6 months of the index PCI in patients with renal dysfunction progression. Furthermore, patients with renal dysfunction progression had poorer long-term renal outcomes.

A novel risk assessment model of contrast-induced nephropathy after percutaneous coronary intervention in patients with diabetes

The purpose of our study was to develop a simple clinical pre-procedure risk model based on clinical characteristics for the prediction of contrast-induced nephropathy (CIN) and major adverse cardiac events (MACEs) after percutaneous coronary intervention (PCI) in patients with diabetes. A total of 1113 patients with diabetes who underwent PCI with contrast exposure were randomized into a development group (n = 742) and a validation group (n = 371) in a 2:1 ratio. CIN was defined as an increase of either 25% or 0.5 mg/dL (44.2 μmol/L) in serum creatinine within 72 hours after contrast infusion. A simple CIN risk score based on independent predictors was established. Four variables were identified for our risk score model: LVEF < 40%, acute coronary syndrome (ACS), eGFR < 60, and contrast volume > 300 mL. Based on this new CIN risk score, the incidence of CIN had a significant trend with increased predicting score values of 5.9%, 32.9% and 60.0%, corresponding to low-, moderate- and high-risk groups, respectively. The novel risk assessment exhibited moderate discrimination ability for predicting CIN, with an AUC of 0.759 [95% CI 0.668-0.852, P = .001] in the validation cohort. It also had similar prognostic values for one-year follow-up MACE (C-statistic: 0.705 and 0.606 for new risk score and Mehran score, respectively). This novel risk prediction model could be effective for preventing nephropathy in diabetic patients receiving contrast media during surgical procedures.

When to use intravascular ultrasound or optical coherence tomography during percutaneous coronary intervention?

Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) are intravascular imaging technologies widely used in the cardiac catheterization laboratory. The impact of these modalities for optimizing the acute and longer-term clinical impact following percutaneous coronary intervention (PCI) is supported by a wealth of clinical evidence. Intravascular imaging provides unique information for enhanced lesion preparation, optimal stent sizing, recognizing post PCI complications, and the etiology of stent failure. This review compares and contrasts the key aspects of these imaging modalities during PCI.

Trajectory of renal function change and kidney injury after percutaneous coronary intervention in patients with stable coronary artery disease

Acute kidney injury usually assessed within 48 h after percutaneous coronary intervention (PCI) is associated with poor clinical outcomes, and persistent kidney damage is also strongly related to long-term mortality. However, little is known about longitudinal renal function change from a very early period to long-term follow-up after PCI. A total of 327 patients with stable coronary artery disease underwent elective PCI. Renal function was assessed with serum creatinine levels and estimated glomerular filtration rate (eGFR) at baseline, 1 day after PCI, at 1 year and at the latest follow-up. Kidney injury was defined as an increase in creatinine levels ≥ 0.3 mg/dl or ≥ 50% from baseline at each timepoint. Major adverse cardiovascular events (MACE) was defined as a composite of death, myocardial infarction, and stroke. eGFR was significantly increased 1 day after PCI, while it was progressively decreased at 1-year and long-term follow-up (median 28 months). Overall, eGFR was declined by - 2.3 ml/min/1.73 m² per year. Only one (0.3%) patient developed kidney injury 1 day after PCI, whereas kidney injury at 1-year and long-term follow-up was observed in 15 (4.6%) and 27 (8.3%). During the follow-up period, 23 (7.0%) patients had MACE. The incidence of subsequent MACE was significantly higher in patients with kidney injury at 1 year than those without. In conclusion, kidney injury within 24 h after elective PCI was rarely observed. eGFR was progressively decreased over time, and mid-term kidney injury at 1 year was associated with future MACE.

Remote ischemic preconditioning reduces the incidence of contrast-induced nephropathy in patients undergoing coronary angiography/intervention: Systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Contrast-induced nephropathy (CIN) is associated with increased mortality and morbidity in patients undergoing coronary angiography (CAG) and percutaneous coronary intervention (PCI). We aimed to assess the latest evidence on the effect of remote ischemic preconditioning (RIPC) on the incidence of CIN in patients undergoing CAG/PCI.

METHODS

We performed a comprehensive search on topics assessing RIPC and CIN in CAG/PCI patients from inception up until July 2019 through several electronic databases.

RESULTS

There were a total of 1,925 subjects from 14 randomized controlled trials. Remote ischemic preconditioning was associated with reduced CIN incidence in patients undergoing CAG/PCI (OR 0.41 [0.30, 0.55], p < .001; I² : 22%). The nephroprotective effect was also demonstrated in those at moderate-high risk for CIN subgroup (OR 0.41 [0.29, 0.58], p < .001; I² : 26%) and PCI-only subgroup (OR 0.41 [0.29, 0.58], p < .001; I² : 0%). Time from RIPC to CAG/PCI has similar effectiveness among ≤45, ≤60, and ≤120 min. Mortality, rehospitalization, hemodialysis, and major adverse events were lower in the RIPC group (OR 0.50 [0.33, 0.76], p = .001; I² : 0%). Grading of recommendations assessment, development and evaluation (GRADE) assessment showed that RIPC has high evidence certainty for reducing CIN in patients undergoing PCI/CAG, moderate-high risk subgroup, and PCI-only subgroup with absolute reduction of 97 per 1,000, 129 per 1,000, and 121 per 1,000, respectively. Harbord test showed no evidence for the presence of small-study effects (p = .157).

CONCLUSIONS

Remote ischemic preconditioning is an effective procedure to reduce the risk of CIN and should be considered in patients with moderate-high risk at developing CIN.

Persistent Renal Dysfunction in Patients Undergoing Primary Percutaneous Coronary Intervention for Acute Myocardial Infarction

Background The long-term prognosis of patients with acute myocardial infarction who develop persistent renal dysfunction (RD) remains unclear. We investigated risk factors and prognostic implications of persistent RD after contrast-induced nephropathy (CIN) in patients with acute myocardial infarction after primary percutaneous coronary intervention. Methods and Results We enrolled 952 consecutive patients who underwent primary percutaneous coronary intervention for acute myocardial infarction. CIN was defined as an increase in serum creatinine levels ≥0.5 mg/dL or ≥25% from baseline within 72 hours after percutaneous coronary intervention. Persistent RD was defined as residual impairment of renal function over 2 weeks, and transient RD was defined as recovery of renal function within 2 weeks, after CIN. The overall incidence of CIN was 8.8% and that of persistent CIN was 3.1%. A receiver-operator characteristic curve showed that the optimal cutoff value of the contrast volume/baseline estimated glomerular filtration rate ratio for persistent CIN was 3.45. In multivariable logistic analysis, a contrast volume/baseline estimated glomerular filtration rate >3.45 was an independent correlate of persistent RD. At 3 years, the incidence of death was significantly higher in patients with persistent RD than in those with transient RD (P=0.001) and in those without CIN (P<0.001). Cox regression analysis showed that persistent RD (hazard ratio, 4.99; 95% CI, 2.30-10.8; P<0.001) was a significant risk factor for mortality. A similar trend was observed for the combined end points, which included mortality, hemodialysis, stroke, and acute myocardial infarction. Conclusions Persistent RD, but not transient RD, is independently associated with long-term mortality. A contrast volume/baseline estimated glomerular filtration rate >3.45 is an independent predictor of persistent RD.

Impact of intravascular ultrasound-guided drug-eluting stent implantation on patients with chronic kidney disease: Results from ULTIMATE trial

OBJECTIVES

This study aimed to investigate the impacts of intravascular ultrasound (IVUS)-guided drug-eluting stent (DES) implantation on patients with chronic kidney disease (CKD) based on the ULTIMATE trial.

BACKGROUND

IVUS-guided DES implantation improves clinical outcomes in complex lesions. However, routine IVUS guidance in patients with CKD remains controversial.

METHODS

CKD was defined as an estimated glomerular filtration rate (eGFR) <60 mL min^-1 1.73 m^-2 . The primary end point was target vessel failure (TVF) at 12 months, including cardiac death, target vessel myocardial infarction, and clinically driven target vessel revascularization.

RESULTS

eGFR was available in 1,443 patients, of whom 723 were in the IVUS guidance group, and 720 were in the angiography guidance group. Finally, CKD was present in 349 (24.2%) patients. At 12 months, TVF in the CKD group was 7.2%, which was significantly higher than 3.2% in the non-CKD group (p = .001). Moreover, there were 25 TVFs in the CKD patients, with 7 (3.9%) TVFs in the IVUS group and 18 (10.7%) TVFs in the angiography group (hazard ratio [HR]: 0.35; 95% confidence interval [CI]: 0.15-0.84; p = .01), whereas 35 TVFs occurred in patients without CKD, with 14 (2.6%) TVFs in the IVUS group and 21 (3.8%) TVFs in the angiography group (HR: 0.67; 95% CI: 0.34-1.32; p = .25; p for interaction = .24).

CONCLUSIONS

This study demonstrated that CKD patients undergoing DES implantations were associated with a higher risk of TVF at 12 months. More importantly, the risk of TVF in the CKD patients could be significantly decreased through IVUS guidance.

CLINICAL TRIAL

NCT02215915.