Prognostic value of chronic total occlusions detected on coronary computed tomographic angiography

The added value of coronary CTA in chronic total occlusion percutaneous coronary intervention: a systematic review and meta-analysis

OBJECTIVES

To systematically investigate and summarize the utility of coronary computed tomographic angiography (CCTA) in the management of chronic total occlusion (CTO)-percutaneous coronary intervention (PCI).

METHODS

The authors searched the four databases between 2005 and 2023 for studies investigating the role of CCTA and invasive coronary angiograms (ICA) images when used as the pre-procedural tool for CTO-PCI. Efficacy and safety of CCTA in CTO-PCI treatment as a pre-procedural assessment tool was evaluated.

RESULTS

Forty-seven studies were finally chosen for this systematic review. CCTA had a high degree of agreement with ICA when applied for J-CTO scoring system. A J-CTO (Multicenter CTO Registry in Japan) score > 3, together with calcification, occlusion length ≥ 20 mm, blunt stump, and bending > 45° were shared imaging risk factors on both ICA and CCTA for technique failure and guidewire crossing over 30 min. Additionally, negative remodeling and multiple diseased vessel were significant indicators on CCTA. Although patients with pre-procedural CCTA showed a trend of higher success rate and easier guidewire crossing, and CCTA showed a slightly higher predictive accuracy for process success, no significant improvement in post-PCI major adverse cardiac events of using CCTA for assessment has been achieved.

CONCLUSIONS

CCTA is a safe and effective pre-operative tool of CTO-PCI. Except for the shared imaging risk factors with ICA for a hard CTO-PCI including calcification, occlusion length ≥ 20 mm, blunt stump, bending > 45°, and J-CTO score > 3, factors like negative remodeling and multiple diseased vessel were also recognized as significant pre-operative assessment indicators on CCTA.

CLINICAL RELEVANCE STATEMENT

A pre-procedural assessment based on coronary computed tomographic angiography has the potential to aid in the management of chronic total occlusion percutaneous coronary intervention.

KEY POINTS

• A coronary computed tomographic angiography-based pre-procedural assessment can help chronic total occlusion-percutaneous coronary intervention management. • The recognized high-risk features detected via coronary computed tomographic angiography and invasive coronary angiograms are comparable in detecting difficult lesions and chronic total occlusion-percutaneous coronary intervention failure. • Coronary computed tomographic angiography has an additional value to be a safe and effective pre-procedural assessment tool for chronic total occlusion-percutaneous coronary intervention.

Computed Tomography Radiomics Model Predicts Procedure Success of Coronary Chronic Total Occlusions

BACKGROUND

Coronary computed tomography (CT) angiography imaging is useful for the preprocedural evaluation of chronic total occlusion (CTO). However, the predictive value of CT radiomics model for successful percutaneous coronary intervention (PCI) has not been studied. We aimed to develop and validate a CT radiomics model for predicting PCI success of CTOs.

METHODS

In this retrospective study, a radiomics-based model for predicting PCI success was developed on the training and internal validation sets of 202 and 98 patients with CTO, collected from 1 tertiary hospital. The proposed model was validated on an external test set of 75 CTO patients enrolled from another tertiary hospital. CT radiomics features of each CTO lesion were manually labeled and extracted. Other anatomical parameters, including occlusion length, entry morphology, tortuosity, and calcification burden, were also measured. Fifteen radiomics features, 2 quantitative plaque features, and CT-derived Multicenter CTO Registry of Japan score were used to train different models. The predictive values of each model were evaluated for predicting revascularization success.

RESULTS

In the external test set, 75 patients (60 men; 65 years [58.5, 71.5]) with 83 CTO lesions were assessed. Occlusion length was shorter (13.00 mm versus 29.30 mm, P=0.007) in PCI success group whereas the presence of tortuous course was more commonly presented in PCI failure group (1.49% versus 25.00%, P=0.004). The radiomics score was significantly smaller in PCI success group (0.10 versus 0.55, P<0.001). The area under the curve of CT radiomics-based model was significantly higher than that of CT-derived Multicenter CTO Registry of Japan score for predicting PCI success (area under the curve=0.920 versus 0.752, P=0.008). The proposed radiomics model accurately identified 89.16% (74/83) CTO lesions with procedure success.

CONCLUSIONS

CT radiomics-based model outperformed CT-derived Multicenter CTO Registry of Japan score for predicting PCI success. The proposed model is more accurate than the conventional anatomical parameters to identify CTO lesions with PCI success.

Cardiovascular Imaging in China: Yesterday, Today, and Tomorrow

The high prevalence and mortality of cardiovascular diseases in China's large population has increased the use of cardiovascular imaging for the assessment of conditions in recent years. In this study, we review the past 20 years of cardiovascular imaging in China, the increasingly important role played by cardiovascular computed tomography in coronary artery disease and pulmonary embolism assessment, magnetic resonance imaging's use for cardiomyopathy assessment, the development and application of artificial intelligence in cardiovascular imaging, and the future of Chinese cardiovascular imaging.

The Role of Multimodality Imaging for Percutaneous Coronary Intervention in Patients With Chronic Total Occlusions

Background

Percutaneous coronary intervention (PCI) of Chronic total occlusions (CTOs) has been traditionally considered a challenging procedure, with a lower success rate and a higher incidence of complications compared to non-CTO-PCI. An accurate and comprehensive evaluation of potential candidates for CTO-PCI is of great importance. Indeed, assessment of myocardial viability, left ventricular function, individual risk profile and coronary lesion complexity as well as detection of inducible ischemia are key information that should be integrated for a shared treatment decision and interventional strategy planning. In this regard, multimodality imaging can provide combined data that can be very useful for the decision-making algorithm and for planning percutaneous CTO recanalization.

Aims

The purpose of this article is to appraise the value and limitations of several non-invasive imaging tools to provide relevant information about the anatomical characteristics and functional impact of CTOs that may be useful for the pre-procedural assessment and follow-up of candidates for CTO-PCI. They include echocardiography, coronary computed tomography angiography (CCTA), nuclear imaging, and cardiac magnetic resonance (CMR). As an example, CCTA can accurately delineate CTO location and length, distal coronary bed, vessel tortuosity and calcifications that can predict PCI success, whereas stress CMR, nuclear imaging and stress-CT can provide functional evaluation in terms of myocardial ischemia and viability and perfusion defect extension.

Updated diagnostic & prognostic paradigm for CAD: a narrative review

Cardiovascular diseases are the first cause of death globally; early detection of coronary artery disease (CAD) is a challenge for clinicians and radiologists. Over the past 2 decades there have been several improvements in the methods for the assessment of diagnosis and prognosis in patients with suspected CAD; most of these methods are imaging methods and they operate with high-end technologies. Cardiac computed tomography (CCT) as we know it today was introduced in 1998 and has ever progressed with constant pace. The first decade was the technical validation phase of the method while the second decade was the clinical validation phase. CCT has developed an excellent diagnostic and prognostic value; technological development together with radiation dose reduction, contributed to the widening of its clinical indications. The diagnostic value of CCT is particularly important as a first line in symptomatic patients with suspected obstructive CAD and low-to-intermediate cardiovascular risk. It is a test that should come, whenever possible, in front of functional evaluation because of its very high sensitivity and negative predictive value. The prognostic value of CCt is still investigational, even though it is becoming quite evident that the atherosclerotic phenotype plays a major role in the determination of prognosis, and as consequence, in the individualization of optimal pharmacological therapy, especially in the cohort without significant obstructive CAD. Recently, scientific and practical guidelines have been updated taking into account the role of CCT, which is able to provide a reliable and fast diagnosis with an additional resources optimization. Multiple registries and trials have been developed and will be summarized in this review. Recent guidelines highlighted the role of CCT in diagnosing suspected CAD.

A computed tomography algorithm for crossing coronary chronic total occlusions: riding on the wave of the proximal cap and distal vessel segment

With wider adoption of coronary computed tomography angiography (coronary CTA), chronic total occlusions (CTOs) are being increasingly identified and characterised by non-invasive angiography. In particular, the ability of coronary CTA to clearly delineate atherosclerotic plaque, as well as to display three-dimensional vessel trajectories, has garnered particular attention in the context of preprocedural planning and periprocedural guidance of CTO percutaneous coronary intervention (PCI). Single CTO features and combined scoring systems derived from CTA (mostly exceeding the diagnostic performance of the angiographic J‑CTO score) have been used to predict time-efficient guidewire crossing, and thus grade the CTO difficulty level prior to PCI. In addition, the introduction of three-dimensional CTA/fluoroscopy co-registration for periprocedural navigation during CTO PCI offers the unprecedented opportunity to resolve proximal cap ambiguity and clearly visualise the distal CTO segment, thereby potentially influencing CTO PCI strategies and techniques. In this review, the potential advantages of non-invasive evaluation of CTO by coronary CTA are described, and a CTA-based hybrid algorithm is introduced for further enhancing the efficiency of CTO PCI. Further studies are clearly needed to verify the proposed approach. However, several luminary operators have already implemented coronary CTA for planning and periprocedural guidance of CTO interventions using the hybrid algorithm.

Efficacy of Coronary Computed Tomography Angiography for the De Novo Detection of Chronic Total Occlusion Prior to Coronary Angiography: A Preliminary and Retrospective Study

Coronary computed tomography angiography (CCTA) offers high-resolution anatomic characterization of the coronary vasculature but may be suboptimal for lesions dependent on real-time visualization of flow including chronic total occlusion (CTO). In CTOs, heavy calcification and distal vessel opacification from collateralization may confound luminal assessment. Several studies have examined the role of CCTA in characterizing known CTOs to guide percutaneous coronary intervention (PCI). However, the efficacy of CCTA in the de novo diagnosis of CTOs prior to coronary angiography (CAG) has not been demonstrated. A total of 233 consecutive patients who presented for CAG within a 3-month period of having CCTA were retrospectively reviewed. Those patients with prior diagnosis of CTO or prior bypass of the occluded vessels were excluded. Sensitivity and specificity analysis of CCTA in identifying CTOs using CAG as the gold standard was performed. The prevalence of CTO was 21.11% in the population that met criteria for analysis (n = 199). The sensitivity of CCTA in predicting CTO was 57.1%, while the specificity was 96.8%. The positive predictive value and negative predictive value of CCTA in detection of CTO were 82.8 and 89.4%, respectively. Our study shows that CCTA has excellent specificity but poor sensitivity in the detection of CTO thus limiting its clinical use in de novo diagnosis. Further studies to determine the effect of de novo CTO diagnosis on clinically important procedural factors, such as radiation exposure, contrast use, and need for repeat procedures, are warranted and may implicate a role for CCTA in this setting.

Assessment of image quality and dose in contrast-enhanced head and neck CT angiography of New Zealand rabbit

BACKGROUND

Although computed tomography (CT) is a powerful diagnostic imaging modality for diagnosing vascular diseases, it is some what risky to human health due to the high radiation dosage. Thus, CT vendors have developed low dose computed tomography (LDCT) aiming to solve this problem. Nowadays, LDCT has gradually become a main stream of CT examination.

OBJECTIVE

This study aimed to assess the feasibility of LDCTAin an animal model and compare the imaging features and doses in two clinical scanners.

METHODS

Twenty-two New Zealand rabbit head and neck CTA images pre- and post-contrast agent injection were performed using256-sliceand 64-slice CT scanners. The tube voltages used in the 256-slice and the 64-slice CTA were 70 kVp and 80 kVp, respectively. Quantitative images indices and radiation doses obtained from CTA in these two scanners were compared.

RESULTS

More neck arterial vessels could be visualized in multi-planar reconstruction (MPR) CTA on the 256-slice CT scanner than on the 64-slice CT scanner. After contrast agent injection, all observed neck arterial vessels had higher CT numbers in 256-slice CTA than in 64-slice CTA. There was no significant difference in contrast-to-noise (CNR) of CTA images between these two scanners. CT dose index (CTDI) and dose length product (DLP) for the 256-slice CTA were lower than those for the 64-slice CTA.

CONCLUSIONS

Low dose CTA of rabbits with 70 or 80 kVp is feasible in a 256-slice or a 64-slice CT scanner. The radiation dose from the 256-slice CTA was much lower than that from the 64-slice CTA with comparable SNR and CNR. The technique can be further applied in longitudinal monitoring of an animal stroke model in the future.