Comparison of usefulness of percutaneous coronary intervention guided by angiography plus computed tomography versus angiography alone using intravascular ultrasound end points

The Role of Multimodality Imaging (CT & MR) as a Guide to the Management of Chronic Coronary Syndromes

Chronic coronary syndrome (CCS) is one of the leading cardiovascular causes of morbidity, mortality, and use of medical resources. After the introduction by international guidelines of the same level of recommendation to non-invasive imaging techniques in CCS evaluation, a large debate arose about the dilemma of choosing anatomical (with coronary computed tomography angiography (CCTA)) or functional imaging (with stress echocardiography (SE), cardiovascular magnetic resonance (CMR), or nuclear imaging techniques) as a first diagnostic evaluation. The determinant role of the atherosclerotic burden in defining cardiovascular risk and prognosis more than myocardial inducible ischemia has progressively increased the use of a first anatomical evaluation with CCTA in a wide range of pre-test probability in CCS patients. Functional testing holds importance, both because the role of revascularization in symptomatic patients with proven ischemia is well defined and because functional imaging, particularly with stress cardiac magnetic resonance (s-CMR), gives further prognostic information regarding LV function, detection of myocardial viability, and tissue characterization. Emerging techniques such as stress computed tomography perfusion (s-CTP) and fractional flow reserve derived from CT (FFRCT), combining anatomical and functional evaluation, appear capable of addressing the need for a single non-invasive examination, especially in patients with high risk or previous revascularization. Furthermore, CCTA in peri-procedural planning is promising to acquire greater importance in the non-invasive planning and guiding of complex coronary revascularization procedures, both by defining the correct strategy of interventional procedure and by improving patient selection. This review explores the different roles of non-invasive imaging techniques in managing CCS patients, also providing insights into preoperative planning for percutaneous or surgical myocardial revascularization.

Appropriateness criteria for the use of cardiac computed tomography, SIC-SIRM part 2: acute chest pain evaluation; stent and coronary artery bypass graft patency evaluation; planning of coronary revascularization and transcatheter valve procedures; cardiomyopathies, electrophysiological applications, cardiac masses, cardio-oncology and pericardial diseases evaluation

In the past 20 years, cardiac computed tomography (CCT) has become a pivotal technique for the noninvasive diagnostic workup of coronary and cardiac diseases. Continuous technical and methodological improvements, combined with fast growing scientific evidence, have progressively expanded the clinical role of CCT. Randomized clinical trials documented the value of CCT in increasing the cost-effectiveness of the management of patients with acute chest pain presenting in the emergency department, also during the pandemic. Beyond the evaluation of stents and surgical graft patency, the anatomical and functional coronary imaging have the potential to guide treatment decision-making and planning for complex left main and three-vessel coronary disease. Furthermore, there has been an increasing demand to use CCT for preinterventional planning in minimally invasive procedures, such as transcatheter valve implantation and mitral valve repair. Yet, the use of CCT as a roadmap for tailored electrophysiological procedures has gained increasing importance to assure maximum success. In the meantime, innovations and advanced postprocessing tools have generated new potential applications of CCT from the simple coronary anatomy to the complete assessment of structural, functional and pathophysiological biomarkers of cardiac disease. In this complex and revolutionary scenario, it is urgently needed to provide an updated guide for the appropriate use of CCT in different clinical settings. This manuscript, endorsed by the Italian Society of Cardiology (SIC) and the Italian Society of Medical and Interventional Radiology (SIRM), represents the second of two consensus documents collecting the expert opinion of cardiologists and radiologists about current appropriate use of CCT.

Practical utilization of cardiac computed tomography for the success in complex coronary intervention

Percutaneous coronary intervention (PCI) for complex lesions is still technically demanding and is associated with less favorable procedural parameters such as lower success rate, longer procedural time, higher contrast volume and unexpected complications. Because the conventional angiographic analysis is limited by the inability to visualize the plaque information and the occluded segment, cardiac computed tomography has evolved as an adjunct to invasive angiography to better characterize coronary lesions to improve success rates of PCI. Adding to routine image reconstructions by coronary computed tomography angiography, the thin-slab maximum intensity projection method, which is a handy reconstruction technique on an ordinary workstation, could provide easy-to-understand images to reveal the anatomical characteristics and the lumen and plaque information simultaneously, and then assist to build an in-depth strategy for PCI. Especially in the treatment of chronic total occlusion lesion, these informations have big advantages in the visualization of the morphologies of entry and exit, the occluded segment and the distribution of calcium compared to invasive coronary angiography. Despite of the additional radiation exposure, contrast use and cost for cardiac computed tomography, the precise analysis of lesion characteristics would consequently improve the procedural success and prevent the complication in complex PCI.

Accuracy of RESOLVE score derived from coronary computed tomography versus visual angiography to predict side branch occlusion in percutaneous bifurcation intervention

INTRODUCTION

Visually estimated angiographic V-RESOLVE score was developed as a simple and accurate prediction tool for side branch (SB) occlusion in patients undergoing coronary bifurcation intervention. Data on the use of coronary computed tomography angiography (coronary CTA) for guiding percutaneous coronary intervention in bifurcation lesions is scarce.

OBJECTIVES

We aimed to validate the ability of quantitative CTA-derived RESOLVE score for predicting SB occlusion in coronary bifurcation intervention and to compare its predictive value with that of the angiography-based V-RESOLVE score.

METHODS

We included 363 patients with 400 bifurcation lesions. Angiographic V-RESOLVE score and CTA-derived RESOLVE score were calculated utilizing the weights from the QCA-based RESOLVE score. The scoring systems were divided into quartiles, and classified as the non-high-risk group and the high-risk group. Accuracy was assessed using areas under the receiver-operator characteristic curve (AUC). SB occlusion was defined as any decrease in Thrombolysis in Myocardial Infarction flow grade (including the absence of flow) in the SB after main vessel stenting.

RESULTS

In total, 28 SB occlusions (7%) occurred. CTA-derived RESOLVE and V-RESOLVE scores achieved comparable predictive accuracy (0.709 vs. 0.752, respectively, p = 0.531) for predicting SB occlusion, and the analysis of AUC for each constituent element of the scores did not show any significant difference between CTA and visual angiography. The total net reclassification index was -18.6% (p = 0.194), and there were no significant differences in the rates of SB occlusion in the non-high-risk group (4.9% vs. 3.8%, p = 0.510) and the high-risk group (13.8% vs. 18.6%, p = 0.384) between CTA-derived RESOLVE and V-RESOLVE scores.

CONCLUSIONS

The quantitative CTA-derived RESOLVE score is an accurate and reliable alternative to the visually estimated angiographic V-RESOLVE score for prediction of SB occlusion in coronary bifurcation intervention.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT03709836.

Stent sizing strategies in renal artery stenting: the comparison of conventional invasive renal angiography with renal computed tomographic angiography

Introduction

Randomized trials comparing invasive treatment of renal artery stenosis with standard pharmacotherapy did not show substantial benefit from revascularization. One of the potential reasons for that may be suboptimal procedure technique.

Aim

To compare renal stent sizing using two modalities: three-dimensional renal computed tomography angiography (CTA) versus conventional angiography.

Material and methods

Forty patients (41 renal arteries), aged 65.1 ±8.5 years, who underwent renal artery stenting with preprocedural CTA performed within 6 months, were retrospectively analyzed. In CTA analysis, reference diameter (CTA-D) and lesion length (CTA_LL) were measured and proposed stent diameter and length were recorded. Similarly, angiographic reference diameter (ANGIO_D) and lesion length (ANGIO_LL) as well as proposed stent dimensions were obtained by visual estimation.

Results

The median CTA_D was 0.5 mm larger than the median ANGIO_D (p < 0.001). Also, the proposed stent diameter in CTA evaluation was 0.5 mm larger than that in angiography (p < 0.0001). The median CTA_LL was 1 mm longer than the ANGIO_LL (p = NS), with significant correlation of these variables (r = 0.66, p < 0.0001). The median proposed stent length with CTA was equal to that proposed with angiography. The median diameter of the implanted stent was 0.5 mm smaller than that proposed in CTA (p < 0.0005) and identical to that proposed in angiography. The median length of the actual stent was longer than that proposed in angiography (p = 0.0001).

Conclusions

Renal CTA has potential advantages as a tool adjunctive to angiography in appropriate stent sizing. Careful evaluation of the available CTA scans may be beneficial and should be considered prior to the planned procedure.

Noninvasive Cardiac Imaging in Patients with Known and Suspected Coronary Artery Disease: What is in it for the Interventional Cardiologist?

The long-standing coronary artery disease (CAD) paradigm simplified by the discrimination between patients with or without CAD warrants to be revisited by the insightful information provided by noninvasive cardiac imaging, leading to a comprehensive physiopathological assessment rather than a mainly anatomical approach. This review will address (1) the role of non-invasive cardiac imaging for the appropriate selection of stable patients referred to invasive coronary angiography (ICA), and the evolving concept and prognostic implications of myocardial ischemia; (2) the usefulness of computed tomography coronary angiography for the guidance of percutaneous coronary interventions; and (3) the role and potential clinical impact of novel anatomical and functional non-invasive prognostic markers.

Coronary artery computed tomography as the first-choice imaging diagnostics in patients with high pre-test probability of coronary artery disease (CAT-CAD)

Introduction

The primary diagnostic examination performed in patients with a high pre-test probability of coronary artery disease (CAD) is invasive coronary angiography. Currently, approximately 50% of all invasive coronary angiographies do not end with percutaneous coronary intervention (PCI) because of the absence of significant coronary artery lesions. It is desirable to eliminate such situations. There is an alternative, non-invasive method useful for exclusion of significant CAD, which is coronary computed tomography angiography (CCTA).

Aim

We hypothesize that use of CCTA as the first choice method in the diagnosis of patients with high pre-test probability of CAD may reduce the number of invasive coronary angiographies not followed by interventional treatment. Coronary computed tomography angiography also seems not to be connected with additional risks and costs of the diagnosis. Confirmation of these assumptions may impact cardiology guidelines.

Material and methods

One hundred and twenty patients with indications for invasive coronary angiography determined by current ESC guidelines regarding stable CAD are randomized 1 : 1 to classic invasive coronary angiography group and the CCTA group.

Results

All patients included in the study are monitored for the occurrence of possible end points during the diagnostic and therapeutic cycle (from the first imaging examination to either complete revascularization or disqualification from the invasive treatment), or during the follow-up period.

Conclusions

Based on the literature, it appears that the use of modern CT systems in patients with high pre-test probability of CAD, as well as appropriate clinical interpretation of the imaging study by invasive cardiologists, enables precise planning of invasive therapeutic procedures. Our randomized study will provide data to verify these assumptions.

Korean guidelines for the appropriate use of cardiac CT

The development of cardiac CT has provided a non-invasive alternative to echocardiography, exercise electrocardiogram, and invasive angiography and cardiac CT continues to develop at an exponential speed even now. The appropriate use of cardiac CT may lead to improvements in the medical performances of physicians and can reduce medical costs which eventually contribute to better public health. However, until now, there has been no guideline regarding the appropriate use of cardiac CT in Korea. We intend to provide guidelines for the appropriate use of cardiac CT in heart diseases based on scientific data. The purpose of this guideline is to assist clinicians and other health professionals in the use of cardiac CT for diagnosis and treatment of heart diseases, especially in patients at high risk or suspected of heart disease.

Coronary computed tomography angiography in planning of percutaneous coronary interventions in bifurcation lesions - study design and rationale

Percutaneous treatment of coronary bifurcations is a complex issue due to numerous possible techniques and high risk of complications. Because of increasing interest in non-invasive imaging in interventional cardiology and growing quality of obtained images, we designed a prospective, randomized, single-blinded trial to evaluate the role of coronary computed tomography angiography (CCTA) in the planning of percutaneous coronary interventions (PCI) of bifurcation lesions. Eighty eligible patients scheduled for PCI of bifurcations in stable coronary artery disease will undergo additional CCTA examination and will be randomized 1: 1 to either planning of PCI using angiography and CCTA or to PCI planning with use of angiography alone. Primary endpoints will include PCI strategy (one or two stents), technique, size of implanted stents and direct angiographic effect of the procedure. Immediate PCI effect measured with intravascular ultrasound (IVUS) and the effect on fractional flow reserve (FFR) in the side branch (in a subgroup of patients), as well as plaque morphology assessed in CCTA, patient radiation exposure and amount of contrast will be compared in secondary analysis. The study is intended to clarify the influence of CCTA analysis on the technique and direct effect of PCI of bifurcations and to provide evidence on the relevance of performing a CCTA scan prior to PCI of bifurcation lesions.

Relation between coronary plaque calcium deposits as described by computed tomography coronary angiography and acute results of stent deployment as assessed by intravascular ultrasound

Introduction

The findings from intravascular ultrasound studies on the impact of calcium deposits on the results of stent implantation are conflicting.

Aim

To evaluate whether calcium deposits as assessed by (CTCA) influence results of stent deployment.

Material and methods

The study population comprised 60 patients (43 male; age 64.2 ±8.6 years) who underwent CTCA before stent implantation. Lesion calcium score, total calcium length, and maximal area and maximal thickness of calcium deposits within the lesion segment were assessed. Plaques were divided into those with calcium score ≥ median (group 1), calcium score < median (group 2), and without calcium (group 3). Intravascular ultrasound (IVUS) was performed after attainment of optimal angiographic results of the stent procedure. Focal and diffuse stent expansion was defined as either minimum stent area (MSA) or mean stent area over the length of the stent divided by reference lumen area.

Results

The proximal reference segments of lesions with higher calcium score contained a larger plaque burden (47 ±12% vs. 41 ±9% vs. 34 ±18%, p = 0.02) – respectively for groups 1, 2, and 3. Positive correlation was observed between lesion calcium score and frequency of post-dilation (R = 0.28, p = 0.03). There was no difference in focal stent expansion (71 ±14% vs. 65 ±15% vs.71 ±15%, p = 0.3) or diffuse stent expansion (92 ±30% vs. 85 ±30% vs. 93 ±38%, p = 0.7) comparing groups 1, 2, and 3. Lesion calcium score, total length of calcium, and maximum area and thickness of calcium deposits did not correlate with focal or diffuse stent expansion.

Conclusions

Lesions with a higher CTCA calcium score had larger reference plaque burden after stent implantation and more likely required post-dilation, but final stent expansion as assessed by IVUS was not affected by the amount of CTCA calcium provided an angiographically optimal result was achieved.

Comparison of stent length reported by the stent's manufacturer to that determined by quantitative coronary angiography at the time of implantation versus that determined by coronary computed tomographic angiography at a later time

The aim of this study was to assess whether coronary computed tomographic angiography (CCTA) would allow accurate length measurements that may help select optimal stent length. In 19 patients who underwent stent implantation and CCTA, the lengths of 30 implanted stents were assessed independently using quantitative coronary angiography (QCA) at the time of implantation and CCTA during follow-up. Measurements on CCTA and QCA were compared with the actual lengths of the implanted stents. The mean actual stent length was 17.3 ± 6.3 mm; the mean length of the stents measured using CCTA was 17.25 ± 5.54 mm, and the mean length of the stents measured using QCA was 15.92 ± 5.86 mm. There was a stronger positive correlation between measurements on CCTA versus actual stent lengths (R = 0.99, p = 0.0001) than between measurements on QCA versus actual stent lengths (R = 0.82, p = 0.0001) (p <0.0001 for the difference between correlation coefficients). In conclusion, the length measurements obtained with CCTA correlate better with an anatomic gold standard (actual stent lengths) than those obtained using QCA.

Extraluminal atherosclerosis: an under-recognised finding in human aortocoronary venous bypass grafts

BACKGROUND

Coronary artery bypass grafting (CABG) is commonly compromised by graft atherosclerosis. Histopathologic studies confirm various forms of atherosclerosis, including positively remodelled lesions in native coronary arteries but there are no histopathologic reports of extraluminal atherosclerosis in vein grafts.

METHODS

We prospectively investigated the histopathologic presence and pattern of extraluminal atherosclerosis in human old vein grafts in a two-year interval among patients undergoing redo-CABG at three university hospitals in Tehran. We separately documented clinical and angiographic findings.

RESULTS

We evaluated 100 segments from 20 human old vein grafts obtained during the redo CABG. All but four segments demonstrated some degrees of luminal narrowing. Luminal atherosclerotic plaques were detectable in 61 segments. We detected extraluminal atheroscleoris in seven segments. Mean vessel wall thickness was greater in segments containing extraluminal plaques (1.41±0.26 mm versus 0.91±0.04 mm, P=0.008). Angiographic findings had a modest correlation with presence or absence of luminal atheromatous lesions (Spearman's rho: 0.331, P=0.007). Angiographic degree of stenosis could not predict the presence of positively remodelled atherosclerotic plaques (Spearman's rho: -2.21, P=0.073).

CONCLUSION

Previous studies suggested positive remodelling in vein grafts. Out study provides histopathologic evidence on extraluminal atherosclerosis in human aortocoronary vein grafts.