Impact of Eruptive vs Noneruptive Calcified Nodule Morphology on Acute and Long-Term Outcomes After Stenting

Predictors of Optical Coherence Tomography-Defined Calcified Nodules in Patients With Acute Coronary Syndrome - A Substudy From the TACTICS Registry

BACKGROUND

Recent studies suggest that the presence of calcified nodules (CN) is associated with worse prognosis in patients with acute coronary syndrome (ACS). We investigated clinical predictors of optical coherence tomography (OCT)-defined CN in ACS patients in a prospective multicenter registry.

METHODS AND RESULTS

We investigated 695 patients enrolled in the TACTICS registry who underwent OCT assessment of the culprit lesion during primary percutaneous coronary intervention. OCT-CN was defined as calcific nodules erupting into the lumen with disruption of the fibrous cap and an underlying calcified plate. Compared with patients without OCT-CN, patients with OCT-CN (n=28) were older (mean [±SD] age 75.0±11.3 vs. 65.7±12.7 years; P<0.001), had a higher prevalence of diabetes (50.0% vs. 29.4%; P=0.034), hemodialysis (21.4% vs. 1.6%; P<0.001), and Killip Class III/IV heart failure (21.4% vs. 5.7%; P=0.003), and a higher preprocedural SYNTAX score (median [interquartile range] score 15 [11-25] vs. 11 [7-19]; P=0.003). On multivariable analysis, age (odds ratio [OR] 1.072; P<0.001), hemodialysis (OR 16.571; P<0.001), and Killip Class III/IV (OR 4.466; P=0.004) were significantly associated with the presence of OCT-CN. In non-dialysis patients (n=678), age (OR 1.081; P<0.001), diabetes (OR 3.046; P=0.014), and Killip Class III/IV (OR 4.414; P=0.009) were significantly associated with the presence of OCT-CN.

CONCLUSIONS

The TACTICS registry shows that OCT-CN is associated with lesion severity and poor clinical background, which may worsen prognosis.

Rotational, orbital atherectomy and intravascular lithotripsy for coronary calcified nodules: insights from optical coherence tomography

BACKGROUND

The optimal treatment strategy for coronary calcified nodules (CN) remains uncertain. We aimed to evaluate the efficacy and safety of different calcium modification strategies, including rotational atherectomy (RA), orbital atherectomy (OA), and intravascular lithotripsy (IVL) for managing CN with optical coherence tomography (OCT) guidance.

METHODS

Consecutive patients undergoing OCT-guided percutaneous coronary intervention (PCI) for severely calcified lesions using RA, OA, or IVL between January 2017 and December 2022 were included. Primary endpoint was minimum stent area (MSA) post-PCI. Secondary endpoints included MSA at CN site and 1-year target vessel failure (TVF), defined as a composite of cardiac death, target-vessel myocardial infarction, or target vessel revascularization.

RESULTS

Among 154 patients and 158 lesions, CN was identified in 54 lesions (34.2%) and managed with RA (39%, n = 21), OA (33%, n = 18), or IVL (28%, n = 15). The IVL group exhibited a larger minimal lumen diameter, maximum calcium arc, and maximum calcium thickness. Post-PCI OCT demonstrated comparable MSA (RA: 6.23 ± 0.34 mm², OA: 5.75 ± 0.39 mm², IVL: 6.24 ± 0.46 mm²; p = 0.62) and MSA at CN site (7.17 ± 0.43 mm², 6.46 ± 0.49 mm², 7.86 ± 0.56 mm², respectively; p = 0.55) after adjusting for morphologic factors. The incidence of TVF at 1 year was similar among the group (RA: 19.0%, OA: 22.2%, IVL: 13.3%, p = 0.81).

CONCLUSIONS

In patients undergoing PCI for CN, similar procedural and clinical outcomes can be achieved using RA, OA, or IVL. These findings warrant further investigation in larger, prospective trials.

Serial Optical Coherence Tomography Assessment of Coronary Atherosclerosis and Long-Term Clinical Outcomes

BACKGROUND

The impact of high-risk coronary artery plaques identified using optical coherence tomography on late luminal narrowing and clinical events remains poorly understood.

METHODS AND RESULTS

This multicenter prospective study included 176 patients who underwent percutaneous coronary intervention and serial optical coherence tomography at baseline and 1-year follow-up to investigate nontarget regions with angiographically intermediate stenosis. At 1 year after percutaneous coronary intervention, the coronary artery lumen area decreased significantly from 6.06 (95% CI, 5.60-6.53) mm2 to 5.88 (95% CI, 5.41-6.35) mm2 (difference, -0.18; 95% CI, -0.22 to -0.14 mm2; P<0.001), particularly in thin-cap fibroatheromas, thick-cap fibroatheromas, mixed plaques, and fibrous plaques. The prevalence of fibroatheroma decreased from 38% to 36% (P<0.001), whereas calcified plaque increased from 31% to 34% (P<0.001), accompanied by a significant increase in calcium thickness and angle. Diabetes and current smoking habits were independently associated with increasing calcium prevalence. Patients with thin-cap fibroatheroma had a significantly higher 3-year risk of ischemia-driven nontarget vessel revascularization (hazard ratio, 2.42 [95% CI, 1.03-5.71]; P=0.04), primarily due to revascularization in the imaged region. No significant association was observed between coronary artery calcium prevalence and clinical outcomes within 3 years.

CONCLUSIONS

The coronary artery lumen area significantly decreased over a 1-year interval, particularly in thin-cap fibroatheromas, thick-cap fibroatheromas, mixed plaques, and fibrous plaques. Although thin-cap fibroatheroma prevalence was associated with higher risk of ischemia-driven nontarget vessel revascularization, no significant association was noted between coronary artery calcium prevalence and clinical outcomes within 3 years. The interaction between calcium progression and long-term clinical events necessitates further investigation.

REGISTRATION

URL: https://www.umin.ac.jp/ctr/; Unique Identifier: UMIN000031937.

Calcified coronary lesions: Imaging, prognosis, preparation and treatment state of the art review

Calcific coronary artery stenosis is a complex disease associated with adverse outcomes and suboptimal percutaneous treatment. Calcium plaque modification has emerged as a key strategy to tackle the issues that accompany calcific stenosis - namely reduced device deliverability, unpredictable lesion characteristics, and difficult dilatation. Atherectomy has traditionally been the treatment modality of choice for heavily calcified coronary stenoses. Contemporary technologies have emerged to aid with planning, preparation, and treatment of calcified coronary stenosis in an attempt to improve procedural success and long-term outcomes. In this State Of The Art Review, we synthesize the body of data surrounding the diagnosis, imaging, and treatment of calcific coronary disease, with a focus on i) intravascular imaging, ii) calcific lesion preparation, iii) treatment modalities including atherectomy, and iv) updated treatment algorithms for the management of calcified coronary stenosis.

A Review Paper on Optical Coherence Tomography Evaluation of Coronary Calcification Pattern: Is It Relevant Today?

The process of coronary calcification represents one of the numerous pathophysiological mechanisms involved in the atherosclerosis continuum. Optical coherence tomography (OCT) represents an ideal imaging modality to assess plaque components, especially calcium. Different calcification patterns have been contemporarily described in both early stages and advanced atherosclerosis. Microcalcifications and spotty calcifications correlate positively with macrophage burden and inflammatory markers and are more frequently found in the superficial layers of ruptured plaques in acute coronary syndrome patients. More compact, extensive calcification may reflect a later stage of the disease and was traditionally associated with plaque stability. Nevertheless, a small number of culprit coronary lesions demonstrates the presence of dense calcified plaques. The purpose of the current paper is to review the most recent OCT data on coronary calcification and the interrelation between calcification pattern and plaque vulnerability. How different calcified plaques influence treatment strategies and associated prognostic implications is of great interest.

In-stent restenosis caused by a reprotruding calcified nodule and stent fracture in the hinged coronary artery

Calcified nodules (CNs) cause in-stent restenosis (ISR) frequently. Although reprotrusion of CNs through stent struts is one of the mechanisms of ISR, the process of this phenomenon has not been understood. Furthermore, little is known about stent fracture (SF) occurring at the site of CNs. We are presenting a case of an 82-year-old male who developed early ISR due to the combination of an in-stent CN and SF in the hinged right coronary artery. The process of progression of the in-stent CN was recorded sequentially with angiography and intravascular ultrasound (IVUS). IVUS from the fulcrum of hinge motion revealed the repetitive protruding movement of the CN into the stent lumen.

Distinct Challenges of Eruptive and Non-Eruptive Calcified Nodules in Percutaneous Coronary Intervention

PURPOSE OF REVIEW

To provide a summary of prevalence, pathogenesis, and treatment of coronary calcified nodules (CNs).

RECENT FINDINGS

CNs are most frequently detected at the sites of hinge motion of severely calcified lesions such as in the middle segment of right coronary artery and left main coronary bifurcation. On histopathology, CNs exhibit two distinctive morphologies: eruptive and non-eruptive. Eruptive CNs, which have a disrupted fibrous cap with adherent thrombi, are biologically active. Non-eruptive CNs, which have an intact fibrous cap without thrombi, are biologically inactive, representing either healed eruptive CNs or protrusion of calcium due to plaque progression. Recent studies using optical coherence tomography (OCT) have shown a difference in the mechanism of stent failure in the two subtypes, demonstrating early reappearance of eruptive CNs in the stent (at ~ 6 months) as a unique mechanism of stent failure that does not seem to be preventable by simply achieving adequate stent expansion. The cause of CN reappearance in stent is not known and could be due to acute or subacute intrusion or continued growth of the CN. Whether modification of CN is needed, the most effective calcium modification modality and effectiveness of stent implantation in eruptive CNs has not been elucidated. In this review, we discuss pathogenesis of CNs and how intravascular imaging can help diagnose and manage patients with CNs. We also discuss medical and transcatheter therapies beyond conventional stent implantation for effective treatment of eruptive CNs that warrant testing in prospective studies.

Mechanism of Stent Failure in Patients With Eruptive Calcified Nodule Treated With Rotational Atherectomy

BACKGROUND

Percutaneous coronary intervention (PCI) for lesions with eruptive calcified nodules (CNs) is associated with worse outcomes compared with that for other calcified lesions. We aimed to clarify the relationship between eruptive CNs at index PCI, optical coherence tomography (OCT) findings at the 8-month follow-up, and clinical outcomes using serial OCT.

METHODS

This retrospective observational study used data from a prospective, single-centre registry. We conducted consecutive PCI for calcified lesions requiring rotational atherectomy (RA) with OCT guidance. We categorized 51 patients (54 lesions) into those with (16 patients [16 lesions]) and without eruptive CNs (35 patients [38 lesions]).

RESULTS

Post-PCI, stent expansion was comparable between the 2 groups, and CN-like protrusion was found in 75% of lesions with eruptive CNs. Follow-up OCT at 8 months revealed in-stent CNs in 54% of treated eruptive CN lesions, whereas lesions without eruptive CNs lacked in-stent CNs. Multivariate linear regression analysis demonstrated that eruptive CN was associated with maximum neointimal tissue (NIT) thickness (regression coefficient 0.303; 95% confidence interval, 0.057-0.549; P = 0.02). Consequently, patients with eruptive CNs exhibited a higher clinically driven target lesion revascularization (TLR) rate than did those without at 1 year (31.3% vs 2.9%, P = 0.009) and 5 years (43.8% vs 11.4%, P = 0.02). TLR primarily occurred in lesions with maximum eruptive CN arc angles > 180°.

CONCLUSIONS

Following RA treatment with acceptable stent expansion, eruptive CNs before PCI correlated with greater NIT formation with in-stent CNs, resulting in a higher TLR rate, particularly in lesions with maximum eruptive CN arc angles exceeding 180°.

Coronary calcified nodules versus nonnodular coronary calcifications: a systematic review and meta-analysis

BACKGROUND

Percutaneous coronary intervention (PCI) on severely calcified coronary lesions is challenging. Coronary calcified nodule (CN) refers to an eccentric and protruding coronary calcification associated with plaque vulnerability and adverse clinical events. This study aims to conduct an extensive review of CNs, focusing on its prognostic impact in comparison with nonnodular coronary calcification (N-CN).

METHOD

A systematic literature review on PubMed, MEDLINE, and EMBASE databases was conducted for relevant articles. Observational studies or randomized controlled trials comparing CNs and N-CNs were included.

RESULTS

Five studies comparing CNs and N-CNs were pertinent for inclusion. The total number of individuals across these studies was 1456. There were no significant differences in the baseline demographic, clinical, and angiographic data between the CN and N-CN groups. Intracoronary imaging was always utilized. At follow-up, CNs were associated with significantly increased, target vessel revascularization [odds ratio (OR) 2.16; 95% confidence interval (CI): 1.39-3.36, P-value < 0.01, I2 = 0%] and stent thrombosis (OR 9.29; 95% CI: 1.67-51.79, P-value = 0.01, I2 = 0%) compared with N-CN. A trend for greater cardiac death was also assessed in the CN group (OR 1.75; 95% CI: 0.98-3.13, P-value = 0.06, I2 = 0%).

CONCLUSION

CN has a significantly negative impact on outcomes when compared with N-CN.

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.

Calcified Nodule in Percutaneous Coronary Intervention: Therapeutic Challenges

Calcified nodules (CNs) are among the most challenging lesions to treat in contemporary percutaneous coronary intervention. CNs may be divided into 2 subtypes, eruptive and noneruptive, which have distinct histopathological and prognostic features. An eruptive CN is a biologically active lesion with a disrupted fibrous cap and possibly adherent thrombus, whereas a noneruptive CN has an intact fibrous cap and no adherent thrombus. The use of intravascular imaging may allow differentiation between the 2 subtypes, thus potentially guiding treatment strategy. Compared with noneruptive CNs, eruptive CNs are more likely to be deformable, resulting in better stent expansion, but are paradoxically associated with worse clinical outcomes, in part because of their frequent initial presentation as an acute coronary syndrome and subsequent reprotrusion of the CN into the vessel lumen through the stent struts. Pending the results of ongoing studies, a tailored therapeutic approach based on the distinct features of the different CNs may be of value.

Unusual optical coherence tomography findings resembling sea anemone tentacles after orbital atherectomy for nodular calcification lesions in a haemodialysis patient: a case report

Background

Optical coherence tomography (OCT) can be used to characterize the details of calcified plaques because it allows high-resolution evaluation of coronary plaques, thrombi, and calcium.

Case summary

A 72-year-old man on haemodialysis who had stenosis with a severe calcified lesion at the left anterior descending artery underwent percutaneous coronary intervention. Pre-intervention OCT imaging identified a nodular calcification (NC) that protruded into the lumen of the left anterior descending artery. To treat this lesion, we performed orbital atherectomy using the Diamondback 360 coronary orbital atherectomy system. After ablation of the nodular lesions at low and high speed, OCT showed newly emerged granular and filamentous structures that resembled sea anemone tentacles (these represented calcified nodule-like OCT findings). These structures appeared to extend from the proximal part of the ablated small NC, and shifted distally after balloon dilatation. Stent implantation was performed to entirely cover these structures, with no resulting complications. However, early in-stent restenosis occurred at 4 months follow-up.

Discussion

A tentacle-like OCT appearance in calcified lesions has not been previously reported. This represents a very rare and interesting imaging finding that reflects the relationship and origins of NCs and calcified nodules. The maturity of the NC lesions and the lateral sanding style of the orbital atherectomy system may have contributed to this striking OCT finding.

Comprehensive clinical outcomes of drug-coated balloon treatment for coronary artery disease. Insights from a single-center experience

BACKGROUND

Some clinical trials have verified the efficacy and safety of paclitaxel drug-coated balloon (DCB) for small vessel coronary artery disease. However, nonsmall vessel and calcified lesions received less attention.

AIMS

This study aimed to investigate the efficacy of DCB treatment for various types of coronary artery lesions, including not only small vessel disease but also nonsmall vessel disease and calcified lesions. In this real-world clinical practice study, in-stent restenosis was excluded.

METHODS

This study consecutively included 934 patients with 1751 nonstented lesions who received DCB at a cardiovascular center in Kyoto Katsura Hospital in Japan between 2009 and 2012 and 2014 to 2019. This study enrolled and retrospectively analyzed all of the patients. Eligible patients routinely underwent follow-up angiography at 6-8 months after percutaneous coronary intervention. The primary endpoint includes target lesion revascularization (TLR) during follow-up. Further, this study calculated the predictor of TLR using multivariate analysis.

RESULTS

This study included the lesions involving 46.4% of type B2/C, 26.9% with severe calcification, and 6.0% with DCB restenosis. Mean DCB diameter and length were 2.75 ± 0.51 mm and 24.2 ± 9.6 mm, respectively. The median follow-up duration was 18 months. Follow-up angiography revealed a TLR rate of 9% and a restenosis rate of 9%. This study identified hemodialysis and current smoking as independent TLR predictors.

CONCLUSION

In routine clinical practice, the effectiveness of DCB was observed consistently across various types of coronary artery disease.

SCAI Expert Consensus Statement on the Management of Calcified Coronary Lesions

The prevalence of calcification in obstructive coronary artery disease is on the rise. Percutaneous coronary intervention of these calcified lesions is associated with increased short-term and long-term risks. To optimize percutaneous coronary intervention results, there is an expanding array of treatment modalities geared toward calcium modification prior to stent implantation. The Society for Cardiovascular Angiography and Interventions, herein, puts forth an expert consensus document regarding methods to identify types of calcified coronary lesions, a central algorithm to help guide use of the various calcium modification strategies, tips for when using each treatment modality, and a look at future studies and trials for treating this challenging lesion subset.

Cardiac Optical Coherence Tomography: History, Current Status, and Perspective

For more than 2 decades since the first imaging procedure was performed in a living patient, intravascular optical coherence tomography (OCT), with its unprecedented image resolution, has made significant contributions to cardiovascular medicine in the realms of vascular biology research and percutaneous coronary intervention. OCT has contributed to a better understanding of vascular biology by providing insights into the pathobiology of atherosclerosis, including plaque phenotypes and the underlying mechanisms of acute coronary syndromes such as plaque erosion, neoatherosclerosis, stent thrombosis, and myocardial infarction with nonobstructive coronary arteries. Moreover, OCT has been used as an adjunctive imaging tool to angiography for the guidance of percutaneous coronary intervention procedures to optimize outcomes. However, broader application of OCT has faced challenges, including subjective interpretation of the images and insufficient clinical outcome data. Future developments including artificial intelligence-assisted interpretation, multimodality catheters, and micro-OCT, as well as large prospective outcome studies could broaden the impact of OCT on cardiovascular medicine.

Comparative Clinical Implications of Calcified versus Non-Calcified Tissue Protrusion After Coronary Stent Implantation

Purpose

The prognostic implications of calcified versus non-calcified tissue protrusions (TPs) following stent implantation remain undetermined. This study aimed to evaluate the differential clinical outcomes associated with calcified and non-calcified TP morphologies.

Patients and Methods

Employing intravascular ultrasound (IVUS), we identified calcified TPs as calcium fragment extrusions permeating the stent struts, while non-calcified TPs were characterized as plaque and/or thrombus extensions through the stent into the arterial lumen. The primary endpoint encompassed target lesion failure (TLF), comprising cardiac death, target vessel myocardial infarction, clinically driven target lesion revascularization (TLR), or stent thrombosis, assessed in patients with a follow-up period exceeding one year.

Results

Of 1033 patients subjected to pre- and post-intervention IVUS, 62 exhibited calcified TPs (6.0%), and 279 presented non-calcified TPs (27.0%), forming the basis of this analysis. Multivariable linear regression indicated calcified nodules as a significant predictor of calcified TP [Odds Ratio (OR) 2.47; 95% Confidence Interval (CI) 2.33 to 2.62; P <0.001], with ST-segment elevation myocardial infarction emerging as an inverse correlate [OR 0.82; 95% CI 0.73 to 0.93; P = 0.004]. Two-year data revealed a higher incidence of TLF in patients with calcified TPs versus their non-calcified counterparts (11.3% vs 2.2%, P <0.001), and a marked increase in clinically driven TLR (9.7% vs 1.4%, P <0.001). Calcified TPs were independently correlated with increased TLF risk in the adjusted model [Hazard Ratio (HR) 2.47; 95% CI 1.17 to 5.16; P = 0.027].

Conclusion

After drug-eluting stent implantation, IVUS-identified calcified TPs correlate with adverse clinical outcomes compared to non-calcified TP formations.

Lifetime management of severely calcified coronary lesions: the treatment algorithm focused on the shape of calcification

The concept of lifetime management has not been discussed in the field of percutaneous coronary intervention (PCI), because the durability of drug-eluting stent (DES) is considered to be long enough for most patients. Furthermore, even if in-stent restenosis occurs, the treatment for in-stent restenosis is simple in most cases. On the other hand, the long-term clinical outcomes after DES implantation are worse in severely calcified coronary lesions than in non-calcified lesions. Moreover, the treatment for in-stent calcified restenosis or restenosis due to stent underexpansion is not simple. The concept of lifetime management of severely calcified lesions may be necessary like that of aortic stenosis. Recently, several algorithms have been published in PCI to severely calcified lesions, partly because of the emergence of IVL. These algorithms focus on the selection of cracking and debulking devices for the preparation of stenting. However, the optimal stent expansion does not guarantee the long-term patency, when the target lesion includes calcified nodules. Stent restenosis due to calcified nodules is difficult to manage. In this review article, we propose the algorithm for severely calcified lesions focused on the shape of calcification. We do not need to hesitate stenting when multiple cracks on circumferential calcification are observed by intravascular imaging devices. However, DCB may be an option as final device in some situations, when lifetime management of severely calcified lesions is considered.

The Role of Intracoronary Imaging for the Management of Calcified Lesions

Interventional cardiologists in everyday practice are often confronted with calcified coronary lesions indicated for percutaneous transluminal coronary angioplasty (PTCA). PTCA of calcified lesions is associated with diverse technical challenges resulting in suboptimal coronary stenting and adverse long-term clinical outcomes. Angiography itself offers limited information regarding coronary calcification, and the adjuvant use of intracoronary imaging such as intravascular ultrasound (IVUS) and Optical Coherence Tomography (OCT) can guide the treatment of calcified coronary lesions, optimizing the different stages of the procedure. This review offers a description of why, when, and how to use intracoronary imaging for PTCA of calcified coronary lesions in order to obtain the most favorable results. We used the PubMed and Google Scholar databases to search for relevant articles. Keywords were calcified coronary lesions, intracoronary imaging, IVUS, OCT, coronary calcium modification techniques, PTCA, and artificial intelligence in intracoronary imaging. A total of 192 articles were identified. Ninety-one were excluded because of repetitive or non-important information.