Introduction

Cardiovascular diseases (CVD) are the most common cause of death, contributing to almost one-third of all deaths around the world [1]. In 2030, according to projections, CVD would cause more than 23 million deaths worldwide [2]. Among these diseases, ischaemic heart disease (IHD) remains the most common cause of death. IHD is estimated to affect 1,655 out of every 100 000 people, amounting to more than 120 million people worldwide [3]. In the vast majority of cases, coronary artery disease (CAD) is caused by a narrowing of the coronary arteries by atherosclerotic plaques.

In the case of significant atherosclerotic involvement of more than one coronary artery or left main coronary artery, one can speak of multivessel coronary artery disease (MVD). Patients with MVD have an increased risk of acute coronary syndromes and sudden cardiac death [4].

To date, many recognised risk factors of CAD have been identified, including an increased low-density lipoprotein (LDL) cholesterol fraction, decreased high-density lipoprotein cholesterol fraction, increased triglycerides, smoking and comorbidities such as hypertension, impaired glucose tolerance or diabetes and atherosclerosis of other arteries. In addition, male gender, older age, genetic predisposition and excessive body weight together with insufficient physical activity contribute to an increased risk of the disease [5].

A number of diagnostic methods are available to help determine the degree of myocardial ischaemia, and thus the approximate degree of stenosis in individual coronary arteries. Non-invasive imaging is an increasingly important option in the diagnostics of IHD, compared to the invasive method — coronary angiography, which was widely used not so long ago [6].

Material and methods

Study design and population

We have conducted a retrospective study of patients with diagnosed MVD and stable angina. One hundred and six participants were enrolled during the period 2020–2022, after hospitalisation in the Cardiology Department of the Central Clinical Hospital in Lodz. Eligible patients were aged 18 years or older, with a diagnosis of CAD according to the European Society of Cardiology Guidelines [7].

The findings of coronary computed tomography angiography (CCTA) and invasive coronary angiography (ICA) in patients with MVD were analysed and the results of the significance of coronary artery stenosis in both imaging methods were compared.

Coronary computed tomography angiography was performed on an outpatient basis in various computed tomography laboratories in the city of Lodz with the use of different CT scanners with a resolution of at least 64 slices. An iodine contrast agent was used in the examination. Significant stenosis of the coronary arteries was defined by the CCTA described as significant, critical, severe or > 70% of the coronary artery lumen.

Invasive coronary angiography was performed in the Cardiology Department of the Central Clinical Hospital in Lodz. Significant stenosis of the coronary arteries in ICA was defined as more than 50% in the left main coronary artery and more than 70% in the rest of the epicardial arteries. ICA was performed no more than 12 months after the CCTA in the same patient.

Exclusion criteria were defined as permanent atrial fibrillation, acute coronary syndrome or stroke within the last 3 months. The study complied with the Declaration of Helsinki and was approved by the local medical ethics committee. Written informed consent was provided by all patients before they participated in the study.

Subjects’ demographic and clinical data

Patient characteristics were collected, such as age, gender, and body mass index (BMI), calculated as weight in kilograms divided by height in meters squared. Clinical information was also acquired from the medical record, such as left ventricular ejection fraction, New York Heart Association functional class, Canadian Cardiovascular Society class, the history of cigarette smoking, alcohol abuse, comorbidities: heart failure, arterial hypertension, hyperlipidaemia, diabetes mellitus type 2, chronic kidney disease, chronic obstructive pulmonary disease and blood tests such as the concentrations of haemoglobin, N-terminal pro-B-type natriuretic peptide, uric acid, LDL, high-density lipoprotein, total cholesterol, triglycerides and estimated glomerular filtration rate.

Data analysis

All the data from the study were analysed using Python SciPy (v1.10) stats library. Graphical data were presented using the matplotlib (v3.6) package. Categorical data were expressed as numbers and as a percentage of the whole study population. Left ventricular ejection fraction was expressed as a percentage of the heart failure patient group. The normal distribution of the continuous variables was assessed using the Shapiro–Wilk test and a histogram.

After the normality analysis, the continuous variables that followed the normal distribution (age and BMI) were presented by means of the standard deviation. Due to the skewed non-normal distribution of other continuous variables, they are described using the median value with lower and upper quartiles. Cohen’s κ was used to determine the concordance between CCTA and ICA results in the assessment of the significance of coronary artery stenosis. The concordance between CCTA and ICA was defined as both examinations showing significant stenosis or an absence of significant stenosis in a coronary artery. In accordance with other authors’ suggestions, the κ values in the range of 0.21–0.4 were identified as a fair agreement and the values 0.41–0.6 as a moderate agreement between the diagnostic methods mentioned above [8].

Results

The study population was predominantly male (n = 69.8%). The average age of the study population was 69.42 ± 8.28 years, with a mean BMI of 27.91 ± 4.44 kg/m2. Chronic heart failure (CHF), chronic kidney disease and diabetes mellitus type 2 were diagnosed in 52.8%, 18.9% and 35.8% of the study population, respectively.

Over 92.5% of the study participants had a history of hypertension, 100% — hyperlipidaemia, and 5.7% — chro­nic obstructive pulmonary disease. Patients’ angina symptoms were most commonly (over 44%) classified as Canadian Cardiovascular Society class II. The detailed characteristics of the study population are presented in Table 1.

The median LDL cholesterol blood concentration was 2.26 mmol/L (1.8–3.02), N-terminal pro-B-type natriuretic peptide: 250.0 pg/mL (100.0–753.8), uric acid: 360.5 µmol/L (298.48–438.78) and estimated glomerular filtration rate was 77.8 mL/min/1.73m2 (62.32–89.78). The remaining biochemical parameters are presented in Table 2.

The comparison of CCTA and coronary angiography results took place in 86 patients because the significance of coronary artery stenosis was not assessed in 20 patients due to an excessively high calcium score preventing the use of an iodine contrast agent.

The concordance in the assessment of the significance of coronary artery stenosis by coronary computed tomo­graphy angiography compared with coronary angiography was 73% (κ = 0.47, moderate agreement). The highest concordance in the assessment was noted for the left main coronary artery (78%, κ = 0.5, moderate agreement) and the lowest for the circumflex branch (69%, κ = 0.34, fair agreement). The detailed analysis is presented in Figure 1 and Table 3.

Figure 1. Comparison between coronary angiography (left bar) and coronary computed tomography angiography (right bar) in the assessment of the significant narrowing in coronary arteries; LAD — left anterior descending artery; LCx — left circumflex artery; LM — left main coronary artery; RCA — right coronary artery

Discussion

Although coronary computed tomography angiography is a very good method for coronary artery imaging, the main advantage of this test remains its high negative predictive value [9]. The exclusion of any coronary artery stenosis by CCTA has been shown to be associated with very low mortality in this group of patients (0.28%) [10]. CCTA has a high sensitivity and specificity (97.2% and 87.4%, respectively) confirmed by numerous studies. Its value increases in patients without a history of CAD (97.6% and 89.2%, respectively) and if the patient’s heart rate is as close as possible to 60/minute or lower [11, 12]. The quality of this method in the assessment of coronary arteries is diminished by past interventions, such as coronary artery bypass grafting or percutaneous coronary intervention with stent implantation. Arrhythmias or fast heart rate and obesity in patients also reduce the specificity of CCTA. However, the technique of the 64-slice resolution or higher minimises these limitations [13, 14].

Thanks to its high sensitivity and specificity, CCTA is an extremely useful method for identifying patients at high risk of cardiovascular incidents, also in the case of an asymptomatic CAD [15, 16].

Coronary angiography remains the “gold standard” for coronary artery imaging. As a diagnostic and therapeutic modality, it allows real-time visualisation of the contrast flow through the vessel and enables a percutaneous intervention to dilate the artery stenosis at the same time. In relation to CCTA, ICA is distinguished by its higher spatial and temporal resolution. Unfortunately, it is an invasive method that carries a risk of complications related to the procedure itself, such as bleeding at the insertion site (0.7%) [17] and the risk of death, myocardial infarction or stroke (0.1–0.2%) [18].

Coronary computed tomography angiography is associated with lower sensitivity and specificity in identifying patients with significant stenosis > 70% of the coronary artery lumen and for the arterial segment [19]. This discrepancy between CCTA and ICA results for the significant stenosis currently precludes the planning of coronary revascularisation using CCTA as a single imaging modality. Nevertheless, non-invasive imaging methods like coronary computed tomography angiography are increasingly likely to be the basis for future qualification for revascularisation including percutaneous coronary angioplasty and coronary artery bypass grafting in patients with MVD as demonstrated by the results of the SYNTAX III study [20].

Still, further research is needed to base future decision-making and treatment planning in MVD patients solely on non-invasive imaging i.e., CCTA, and clinical information.

Limitations

There are several limitations to this study. This study was retrospective and involved only one centre. The CCTA examinations were performed by different laboratories and described by different radiologists, which may influence the assessment of stenosis in coronary arteries. In addition, coronary angiography was also performed by different cardiologists. It must be taken into account that CCTA is often subject to limitations due to the differences in the experience level of doctors describing the test result and the quality of the apparatus on which they were performed.

Conclusions

Coronary risk factors are widespread in patients with MVD which is an important issue and highlights the considerable work that needs to be done in educating society about the prevention of CVD. In patients with MVD, there is a moderate agreement between the description of the significance of coronary artery stenosis based on CCTA compared to ICA which rules out the eligibility of CCTA as a standalone preparation method for interventional treatment of these patients nowadays. Nevertheless, the non-invasive methods are in the process of constant perfecting and they constitute the future of cardiology, which may result in a beneficial impact on patients, for example, a reduction of complications associated with invasive procedures.

Article information

Author contributions

DK — concept author, study design, data collection, writing of the publication; OMB — writing the publication; MK — author of methods, statistical analysis; MJ — data collection, analysis and interpretation of results; MP — data collection, amending the publication; JK — data analysis, amending publications; JD — concept author, writing of publication, approval of final version of article.

Conflict of interest

The authors declare no conflict of interest.

Ethics statement

The study complied with the Declaration of Helsinki and was approved by the local medical ethics committee.

Data availability statement

Various source data from the literature describe the concordance between coronary angiography and coronary artery computed tomography. In this study, authors aimed to address the issue of concordance between computed tomography of the coronary arteries and coronarography in assessing the significance of coronary artery stenosis in patients with multivessel coronary artery disease.

Funding

This work was financed from own resources