Experience and perspective with intravascular imaging and invasive coronary physiology: Insights from allied health professionals.

BACKGROUND: Although intravascular imaging (IVI) and invasive coronary physiology (ICP) are utilized in percutaneous coronary intervention (PCI) with robust positive clinical evidence, their adoption in cardiac catheterization laboratories (CCLs) is still limited. AIMS: The aim of our survey was to assess the perspectives on the experiences of allied health professionals in CCLs' utility of IVI and ICP. METHODS: An anonymous online survey was conducted through multiple channels, including the Cardiovascular Research Technologies (CRT) 2023 Nurses and Technologists Symposium, social media, Cath Lab Digest link, and field requests, leading to diverse representation of allied health professionals. RESULTS: A total of 101 CCL members participated in the survey. First, 59% of responders noted an increased use of IVI in their institutions over recent years. For those experiencing an increase, 49% credited training, 45% emerging evidence, and 34% attributed new CCL members. Barriers to IVI usage were perceived increased procedure time (58%), staff resistance (56%), procedural cost (48%), and difficulty interpreting findings (44%). Regarding ICP, 61% reported using it in approximately 25% to 75% of cases, while 10% utilized it in 75% to 100% of CCL procedures. Interpreting ICP results was mixed, with 56% confident in interpreting all ICP results and 6% unable to interpret any ICP results. CONCLUSION: Our findings highlight opportunities for increasing routine utilization of IVI and ICP in the CCL through allied health professionals. By providing education and training, we can elevate familiarity with the equipment and subsequently build a CCL culture that advocates for both IVI and ICP.

Assessing the efficacy of saline flush in frequency-domain optical coherence tomography for intracoronary imaging.

BACKGROUND: The increased amount of contrast media in frequency-domain optical coherence tomography (FD-OCT) imaging during percutaneous coronary intervention (PCI) has raised potential concerns regarding impairment of renal function. OBJECTIVES: This study aimed to evaluate the effectiveness of heparinized saline flush in FD-OCT-guided PCI and identify clinical factors contributing to optimal image quality. METHODS: We retrospectively collected 100 lesions from 90 consecutive patients, and a total of 200 pullbacks were analyzed for the initial and final evaluation in which saline was used as the flushing medium. RESULTS: The study population had a mean age of 73, with 52% having chronic kidney disease (CKD). The median amount of contrast used was 28 ml, and no complications were observed associated with saline flush OCT. Imaging quality was then categorized as excellent, good, or unacceptable. Among the total runs, 87% demonstrated clinically acceptable image quality, with 66.5% classified as excellent images and 20.5% classified as good images. Independent predictors of excellent images included lumen area stenosis ≥ 70% (adjusted odds ratio [OR] 2.37, 95% confidence interval [CI] 1.02-5.47, P = 0.044), and the use of intensive flushing (adjusted OR 2.06, 95% CI 1.11-3.86, P = 0.023) defined as a deep engagement of guiding catheter (GC) or a selective insertion of guide extension catheter (GE). Intensive flushing was performed in 60% of the total pullbacks, and it was particularly effective in improving image quality in the left coronary artery (LCA). CONCLUSION: The use of saline flush during FD-OCT imaging was safe and feasible, which had a benefit in renal protection with adequate imaging quality.

Intracoronary imaging to guide percutaneous coronary intervention: from evidence to guidelines.

Despite notable advances in devices and techniques, percutaneous coronary intervention (PCI) is still affected by a substantial number of complications and failure rates. Over the years, the use of intracoronary imaging (ICI) has dramatically improved the understanding of mechanical and technical factors related to successful and failed PCI, becoming a mainstay in complex trans-catheter interventions. However, ICI modalities are invasive, time-consuming, and costly, and a net clinical benefit needs to be shown in order to recommend their routine use in clinical practice. In the past, the lack of evidence from randomized trials has been reflected in the scepticism shown by international guidelines. The recent publication of large randomized clinical trials conducted worldwide has provided new evidence regarding the clinical usefulness of ICI guidance in PCI. The consistent reduction of adverse events achieved in these trials, also demonstrated in an updated meta-analysis, suggested that the use of ICI in PCI is compelling to achieve optimal technical results and better outcomes, especially in complex high-risk interventions. Also considering the burden of information provided by ICI on coronary artery disease, looking from the inside seems today an opportunity that modern cardiology cannot ignore anymore.

Intracoronary Diagnostics in Patients with Acute Coronary Syndrome.

Despite the increasing number of coronary interventions in China, long-term adverse cardiovascular events remain high, especially in patients with acute coronary syndromes (ACS). The advent of intracoronary imaging and coronary physiological diagnostic techniques, such as optical coherence tomography (OCT), intravascular ultrasound (IVUS), near infrared spectroscopy (NIRS), and flow reserve fraction (FFR), has optimized the diagnosis and risk classification of patients with ACS. Intracoronary diagnostics compensate for the deficiencies of conventional coronary angiography in identifying and incriminating lesions and high-risk lesions. The combination of intracoronary imaging and physiological techniques is expected to achieve a comprehensive evaluation of the structural features and physiology of the coronary arteries, thus further tailoring and improving the prognosis of patients.

Calcified coronary lesions.

The treatment of calcific coronary lesions is still a major interventional issue in haemodynamics laboratories. The prevalence of the disease is even increasing, considering the general ageing of the population undergoing coronarography, as well as the often associated comorbidities. In recent years, new devices have been developed that allow both better identification and also better treatment of these lesions. The aim of this review is to summarize both imaging modalities and dedicated techniques and materials, thus providing a kind of compendium for the treatment approach.

Intracoronary Imaging of Coronary Atherosclerotic Plaque: From Assessment of Pathophysiological Mechanisms to Therapeutic Implication.

Atherosclerotic cardiovascular disease is the leading cause of morbidity and mortality worldwide. Several cardiovascular risk factors are implicated in atherosclerotic plaque promotion and progression and are responsible for the clinical manifestations of coronary artery disease (CAD), ranging from chronic to acute coronary syndromes and sudden coronary death. The advent of intravascular imaging (IVI), including intravascular ultrasound, optical coherence tomography and near-infrared diffuse reflectance spectroscopy has significantly improved the comprehension of CAD pathophysiology and has strengthened the prognostic relevance of coronary plaque morphology assessment. Indeed, several atherosclerotic plaque phenotype and mechanisms of plaque destabilization have been recognized with different natural history and prognosis. Finally, IVI demonstrated benefits of secondary prevention therapies, such as lipid-lowering and anti-inflammatory agents. The purpose of this review is to shed light on the principles and properties of available IVI modalities along with their prognostic significance.

Risk Factors for Vulnerable Plaque Detected Using Near-Infrared Spectroscopy in Patients Receiving Statin Therapy with No History of Coronary Artery Disease.

Residual risk of atherosclerosis remains high despite the use of lipid-lowering therapy with statins. Near-infrared spectroscopy intravascular ultrasound imaging (NIRS-IVUS) can identify vulnerable plaque via the detection of lipid-rich plaque. This study aimed to reveal the clinical characteristics of patients with vulnerable plaque despite statin therapy.NIRS-IVUS was used to determine the maximum 4 mm Lipid Core Burden Index (MaxLCBI4 mm) values of 38 de novo culprit lesions from 32 patients with acute coronary syndrome (53%) (mean age: 73.1 ± 13.1 years) who underwent percutaneous coronary intervention after a minimum 6 months of statin therapy for primary prevention. A patient with vulnerable plaque was defined as an individual presenting at least 1 target lesion with a vulnerable plaque (MaxLCBI4 mm > 400). Overall, the average low-density lipoprotein cholesterol (LDL-C) level was 95.5 ± 27.2 mg/dL. Patients in the vulnerable plaque group were younger and had higher LDL-C, triglycerides, and non-high-density lipoprotein cholesterol (HDL-C) levels than those in the non-vulnerable plaque group. The MaxLCBI4 mm was positively correlated with LDL-C (P = 0.0002), triglycerides (P = 0.0003), and non-HDL-C (P = 0.0001). In multivariate analysis, all 3 treatable lipid components failed to show an independent relationship with the patients with vulnerable plaque. Using receiver-operating characteristics curve analysis, the cutoff points for LDL-C, triglycerides, and non-HDL-C were determined to be 78 mg/dL, 108 mg/dL, and 111 mg/dL, respectively, at MaxLCBI4 mm > 400. In conclusion, this study supports a more comprehensive and aggressive lipid-lowering therapy for the primary prevention of coronary artery disease.

Imaging in Percutaneous Coronary Intervention.

Intracoronary imaging (ICI) use during percutaneous coronary intervention (PCI) has been shown to effectively improve cardiovascular outcomes, particularly for high-risk subgroups. However, data from randomized controlled trials are limited and the overall utilization rate of ICI remains variable between different countries and centers. Potential benefits of ICI include identification of appropriate lesions for PCI, improved characterization of lesions, and optimization of stent placement. Currently available modalities of ICI include intravascular ultrasound, optical coherence tomography and near infrared spectroscopy. Within this review, we summarize the contemporary evidence surrounding ICI and discuss its application in clinical practice.

Identification and treatment of the vulnerable coronary plaque.

Acute coronary syndrome mostly arises from rupture or erosion of a vulnerable plaque. Vulnerable plaques typically appear as lipid-rich plaques with a thin cap, called thin-cap fibroatheromas. Various intracoronary imaging techniques can be used to detect vulnerable plaques, such as intravascular ultrasound (IVUS), optical coherence tomography (OCT) and near-infrared spectroscopy (NIRS), each visualizing different high-risk plaque characteristics. IVUS and its post-processing techniques, such as virtual histology IVUS, can primarily be used to identify calcified and soft plaques, while OCT is also able to quantitatively measure the cap thickness. The addition of NIRS allows the exact measurement of lipid content in the plaque. Non-invasive imaging techniques to identify vulnerable plaques, such as computed tomography, are less often used but are evolving and may be of additional diagnostic use, especially when prophylactic treatments for vulnerable plaques are further established. Pharmacological treatment with lipid-lowering or anti-inflammatory medication leads to plaque stabilization and reduction of cardiovascular events. Moreover, the implantation of a stent or scaffold for the local treatment of vulnerable plaques has been found to be safe and to stabilize high-risk plaque features. The use of drug-coated balloons to treat vulnerable plaques is the subject of ongoing research. Future studies should focus on non-invasive imaging techniques to adequately identify vulnerable plaques and further randomized clinical studies are necessary to find the most appropriate treatment strategy for vulnerable plaques.

Clinical outcomes for intracoronary imaging strategies at different medical facilities in Japanese patients with coronary artery disease: the SAKURA imaging PCI Registry.

The relationships between intracoronary imaging modalities and outcomes among Japanese patients with coronary artery disease (CAD) based on the type of medical facility providing outpatient care remain unclear. In this multicenter prospective study (SAKURA PCI Registry), we aimed to investigate the clinical outcomes of patients with CAD who underwent percutaneous coronary intervention (PCI) between April 2015 and December 2018. In this registry, we investigated differences in patient characteristics, intracoronary imaging modalities, and clinical outcomes between two types of medical facilities. Of the 414 patients enrolled in this registry, 196 were treated at two university hospitals, and 218 were treated at five community hospitals (median follow-up 11.0 months). The primary endpoint was clinically relevant events (CREs), including a composite of all-cause death, non-fatal myocardial infarction, clinically driven target lesion revascularization, stent thrombosis, stroke, and major bleeding. Patients treated at university hospitals had higher rates of diabetes (50% vs. 38%, p = 0.015) and malignant tumors (12% vs. 6%, p = 0.015) and more frequent use of multiple intracoronary imaging modalities than patients treated at community hospitals (21% vs. 0.5%, p < 0.001). The Kaplan-Meier incidence of CREs at 1 year was comparable between university hospitals and community hospitals (8.8% vs. 7.3%, p = 0.527, log-rank test). Despite the relatively higher risk among patients in university hospitals with frequent use of multi-intracoronary imaging modalities, adverse clinical events appeared to be comparable between patients with CAD treated at university and community hospitals in Japan.

Myocardial bridge evaluation towards personalized medicine: study design and preliminary results of the RIALTO registry.

Myocardial bridge (MB) is the most frequent inborn coronary artery variant in which a portion of the myocardium overlies an epicardial coronary artery segment. Although MB has long been considered a benign entity, a growing body of evidence has suggested its association with angina and adverse cardiac events. However, to date, no data on long-term prognosis are available, nor on therapies improving cardiovascular outcomes. We are currently conducting an ambispective, observational, multicentre, study in which we enrol patients with a clinical indication to undergo coronary angiography (CA) and evidence of MB, aiming to describe the incidence of symptoms and cardiovascular events at baseline and at long-term follow-up (FUP). The role of invasive full-physiology assessment in modifying the discharge therapy and eventually the perceived quality of life and the incidence of major cardiovascular events will be analysed. Basal clinical-instrumental data of eligible and consenting patients have been acquired after CA; FUP was performed 6, 12, and 24 months after the angiographic diagnosis of MB. The primary endpoint of the study is the incidence of major adverse cardiovascular events (MACE), defined as the composite of cardiac death, myocardial infarction, cardiac hospitalization, and target vessel revascularization; the secondary endpoints are the rate of patients with Seattle Angina Questionnaire (SAQ) summary score <70 and the incidence of MACE in patients undergoing invasive intracoronary assessment. Among patients undergone FUP visits, we recorded 31 MACE at 6 months (11.6%), 16 MACE at 12 months (6.5%), and 26 MACE at 24 months (13.5%). The rate of patients with SAQ <70 is 18.8% at 6 months, 20.6% at 12 months, and 21.8% at 24 months. To evaluate the prognostic role of invasive intracoronary assessment, we compared MB patients who underwent only angiographic evaluation (Angio group) to those who underwent acetylcholine (ACH) provocative test with indication to calcium-channel blockers (CCBs) at discharge (Angio + ACH + CCBs group) and those who underwent functional assessment with fractional flow reserve (FFR) with indication to beta-blockers (BBs) at discharge (Angio + FFR + BBs group). After 2 years of FUP, the rate of MACE was significantly reduced in both Angio + ACH + CCBs group (6 vs. 25%, P = 0.029) and Angio + FFR + BBs group (3 vs. 25%, P = 0.005) compared with Angio group. The preliminary results of our study showed that MB may be a cause of angina and adverse cardiac events in patients referred to CA for suspected coronary artery disease (CAD). Full-physiology assessment unmasking MB-related ischaemia mechanisms, allowed to guide the treatment, personalizing the clinical management, improving the quality of life, and cardiovascular outcomes in patients with MB.

Near-Infrared Spectroscopy Intravascular-Ultrasound-Guided Intervention in Minimal Coronary Artery Stenosis: A Case Report.

Near-infrared spectroscopy intravascular ultrasounds (NIRS-IVUSs) can identify high-risk plaque morphologies associated with future event risk. However, the usage of NIRS-IVUSs is not universal. We report a case with insignificant coronary angiography (CAG) and high-risk NIRS-IVUS findings. A 58-year-old man with exertional dyspnea was admitted for a CAG evaluation. The CAG of the patient demonstrated mild angiographic stenosis in the mid-left anterior descending artery. However, NIRS-IVUS revealed a high maximum lipid core burden index at 4 mm (MaxLCBI4mm) and an intraluminal calcific protrusion with severe luminal stenosis at the lesion. Therefore, the patient was diagnosed as stable angina, and a drug-eluting stent was implanted in the lesion. A post-stent NIRS-IVUS demonstrated improved MaxLCBI4mm and significantly improved luminal stenosis. The patient did not have any procedural complications. In the present case, a patient with insignificant CAG demonstrated multiple high-risk features on NIRS-IVUS. Therefore, a percutaneous coronary intervention was performed. The presented case highlights the utility of NIRS-IVUS in nonobstructive CAG.

Breaking the deadlock of calcified coronary artery lesions: A contemporary review.

Percutaneous coronary intervention (PCI) of severely calcified lesions is known to result in lower procedural success rates, higher complication rates, and worse long-term clinical outcomes compared to noncalcified lesions. Adequate lesion preparation through calcium modification is crucial in ensuring procedural success and reducing adverse cardiovascular outcomes. There are numerous calcium modification devices currently available whose usefulness depends on the nature of the calcific disease and its anatomical distribution. It can be challenging for the interventionists to decide which device is best suited for their patient. There is also emerging evidence for intravascular imaging in guiding selection of calcium modification devices using parameters such as calcium distribution and depth that directly impact on procedural success and clinical outcomes. In this review we aim to discuss the pathophysiology of coronary calcification, evaluate strategies and technologies of calcium modification and propose an A-M-A-S-A algorithm in managing calcified coronary lesions.

New interventional solutions in calcific coronary atherosclerosis: drill, laser, shock waves.

In the percutaneous treatment of coronary stenoses, it is essential to take into account the presence of calcifications as this influences the short- and long-term post-procedural outcomes. Today in the catheterization laboratory, there are several tools for the treatment of calcium; exploiting the different operating mechanisms, possibly even combining them together, is part of a modern approach to coronary angioplasty that aims to optimize results. To this end, each procedure must be properly planned and, in this perspective, intracoronary imaging (such as optical coherence tomography and intravascular ultrasound) is an essential aid to guide the procedure and show results.

Recent developments in diagnosis and risk stratification of non-ST-elevation acute coronary syndrome.

In the past year, a number of important papers have been published on non-ST-elevation acute coronary syndrome, highlighting progress in clinical care. The current review focuses on early diagnosis and risk stratification using biomarkers and advances in intracoronary imaging.

Associations of 26 Circulating Inflammatory and Renal Biomarkers with Near-Infrared Spectroscopy and Long-term Cardiovascular Outcome in Patients Undergoing Coronary Angiography (ATHEROREMO-NIRS Substudy).

PURPOSE OF REVIEW: The purpose of this study was to investigate the association of 26 inflammatory biomarkers (acute phase proteins, cytokines, chemokines) and renal markers with coronary lipid core burden index (LCBI) assessed by near-infrared spectroscopy (NIRS) imaging, as well as the association of these biomarkers with long-term cardiovascular outcome. RECENT FINDINGS: NIRS-derived LCBI has recently been shown to be an independent predictor of major adverse cardiac events (MACE). However, studies on the association between circulating biomarkers and NIRS-derived characteristics have not yet been performed. Between 2008 and 2011, 581 patients underwent diagnostic coronary angiography or percutaneous coronary intervention for stable angina pectoris or acute coronary syndrome (ACS). NIRS of a non-culprit vessel was performed in a subset of 203 patients. In multivariable analyses, TNF-α tended to be associated with higher LCBI (beta 0.088 ln (pg/ml) increase per unit LCBI; 95% CI 0.000-0.177, p = 0.05) after adjustment for clinical characteristics. However, this association did not persist after Bonferroni correction (statistical threshold 0.0019). Major adverse cardiac events (MACE) were registered in 581 patients during a median follow-up time of 4.7 years (IQR: [4.2-5.6] years). After adjustment for clinical characteristics and Bonferroni correction, IL-8 (HR 1.60; 95% CI [1.18-2.17] per ln (pg/ml), p = 0.002) was borderline associated with MACE and significantly associated with all-cause mortality or ACS (HR 1.75; 95% CI [1.24-2.48] per ln (pg/ml), p = 0.0015). In conclusion, we found that IL-8 was independently associated with clinical outcome, but altogether, the multiplex panel we investigated here did not render a useful blood biomarker of high LCBI.

Real-time optical coherence tomography coregistration with angiography in percutaneous coronary intervention-impact on physician decision-making: The OPTICO-integration study.

AIMS: Intracoronary optical coherence tomography (OCT) imaging allows for high-resolution characterization of coronary lesions. Difficulties in matching cross-sectional OCT-images with angiographic lesion localization may limit optimal clinical utilization. We sought to prospectively assess the impact of a novel system of real-time OCT coregistration with angiography (ACR) on physician decision-making during percutaneous coronary interventions (PCI). METHODS AND RESULTS: Strategy for PCI (stent - length, - diameter, - strategy, landing zone) and PCI-optimization (stent-malappostion, -underexpansion, edge-dissections, geographical mismatch) was prospectively assessed in 50 patients with 58 coronary lesions after (I) angiography, (II) OCT imaging, and (III) ACR. Preprocedural OCT imaging altered stent-length (58.9%), diameter (33.9%), and PCI-strategy (12.5%) in 40 (71.4%) lesions. The use of ACR resulted in additional changes in PCI strategy in 40.7% of mostly complex lesions in comparison to OCT imaging alone and involved mainly device landing zone (24.1%) and stent length (22.2%). Postprocedural OCT imaging revealed the need for PCI optimization in 52.2% of the lesions, whereas post-procedural ACR had no further impact. CONCLUSIONS: Real-time OCT ACR had significant impact on PCI strategy, favoring mainly complete lesion coverage especially in complex lesions.

Intracoronary imaging of coronary atherosclerosis: validation for diagnosis, prognosis and treatment.

While coronary atherosclerosis is a leading cause of mortality, evaluation of coronary lesions was previously limited to either indirect angiographic assessment of the lumen silhouette or post mortem investigations. Intracoronary (IC) imaging modalities have been developed that allow for visualization and characterization of coronary atheroma in living patients. Used alone or in combination, these modalities have enhanced our understanding of pathobiological mechanisms of atherosclerosis, identified factors responsible for disease progression, and documented the ability of various medications to reverse the processes of plaque growth and destabilization. These methodologies have established a link between in vivo plaque characteristics and subsequent coronary events, thereby improving individual risk stratification, paving the way for risk-tailored systemic therapies and raising the option for pre-emptive interventions. Moreover, IC imaging is increasingly used during coronary interventions to support therapeutic decision-making in angiographically inconclusive disease, guide and optimize procedural results in selected lesion and patient subsets, and unravel mechanisms underlying stent failure. This review aims to summarize current evidence regarding the role of IC imaging for diagnosis and risk stratification of coronary atherosclerosis, and to describe its clinical role for guiding percutaneous coronary interventions. Future perspectives for in-depth plaque characterization using novel techniques and multimodality imaging approaches are also discussed.

Impact of impaired fractional flow reserve after coronary interventions on outcomes: a systematic review and meta-analysis.

BACKGROUND: FFR is routinely used to guide percutaneous coronary interventions (PCI). Visual assessment of the angiographic result after PCI has limited efficacy. Even when the angiographic result seems satisfactory FFR after a PCI might be useful for identifying patients with a suboptimal interventional result and higher risk for poor clinical outcome who might benefit from additional procedures. The aim of this meta-analysis was to investigate available data of studies that examined clinical outcomes of patients with impaired vs. satisfactory fractional flow reserve (FFR) after percutaneous coronary interventions (PCI). METHODS: This meta-analysis was carried out according to the Cochrane Handbook for Systematic Reviews. The Mantel-Haenszel method using the fixed-effect meta-analysis model was used for combining the results. Studies were identified by searching the literature through mid-January, 2016, using the following search terms: fractional flow reserve, coronary circulation, after, percutaneous coronary intervention, balloon angioplasty, stent implantation, and stenting. Primary endpoint was the rate of major adverse cardiac events (MACE). Secondary endpoints included rates of death, myocardial infarction (MI), repeated revascularisation. RESULTS: Eight relevant studies were found including a total of 1337 patients. Of those, 492 (36.8 %) had an impaired FFR after PCI, and 853 (63.2 %) had a satisfactory FFR after PCI. Odds ratios indicated that a low FFR following PCI was associated with an impaired outcome: major adverse cardiac events (MACE, OR: 4.95, 95 % confidence interval [CI]: 3.39-7.22, p <0.001); death (OR: 3.23, 95 % CI: 1.19-8.76, p = 0.022); myocardial infarction (OR: 13.83, 95 % CI: 4.75-40.24, p <0.0001) and repeated revascularisation (OR: 4.42, 95 % CI: 2.73-7.15, p <0.0001). CONCLUSIONS: Compared to a satisfactory FFR, a persistently low FFR following PCI is associated with a worse clinical outcome. Prospective studies are needed to identify underlying causes, determine an optimal threshold for post-PCI FFR, and clarify whether simple additional procedures can influence the post-PCI FFR and clinical outcome.