Coronary artery ectasia (CAE) is a relatively rare coronary artery diseases (CAD) variant. It is characterized by abnormal portion enlargement or the entire length of a coronary artery (CA), measuring at least 1.5 times wider than a nearby normal segment. Ectasia is most often associated with atherosclerotic CAD [1][2]. The incidence of CAE varies significantly, ranging from 0.3 to 12%, as observed in autopsy findings and diagnostic techniques like coronary angiography or multi-detector computed tomography [3]. This variability largely depends on the methods used and the specific population studied [4].

There are several approaches to defining the CAE based on its severity and distribution. Various definitions have been proposed depending on the study methodology. Yang X, et al. [5] described ectasia as a CA segment greater than that of the adjacent normal segment. Meanwhile, Sheikh AS, et al. [6] developed a classification system to categorize CAE based on the extent of arterial involvement: Type I (diffuse in two to three vessels), Type II (diffuse in one vessel and localized in another), Type III (diffuse in a single vessel), and Type IV (localized or segmental dilatation).

In adults, most cases of CAE and CA aneurysms are associated with atherosclerosis or result from vessel wall damage following coronary interventions such as stent placement, balloon angioplasty, and/or atherectomy [7]. In contrast, in early age groups, vasculitic conditions, particularly Kawasaki disease, are more frequent. Less commonly, coronary aneurysms may arise because of factors such as cocaine use or systemic infections [8]. Evidence also suggests a genetic predisposition to the development of both CAE and aneurysms [9].

Aneurysmal dilation often leads to turbulent (sluggish) coronary blood flow, increasing the risk of typical exertional myocardial infarction (MI) and angina irrespective of the associated stenosis. Individuals with isolated CAE — representing ~15% of cases — tend to have a relatively more benign prognosis. However, ~39% of these individuals still exhibit signs of previous MI [10].

Earlier research, which highlighted considerable flow disturbances in ectatic segments, proposed chronic anticoagulation as a primary treatment approach. However, this therapy has not been thoroughly tested in prospective studies; therefore, it cannot be recommended without further supporting evidence from future research. When CAE coexists with obstructive CAD, its prognosis and management are typically aligned with those of CAD alone. However, in cases of isolated CAE, prognosis tends to be more favorable, and antiplatelet therapy remains the cornerstone of treatment [11].

Evidence suggests that CAE may not be as benign as previously believed. The individuals with CA aneurysms presented with a significantly greater 5-year mortality rate, with an adjusted hazard ratio of 1.56 (95% confidence interval (CI): 1.01-2.41) [12]. Another study reported that 54% of patients with coronary aneurysms detected via computed tomography imaging experienced high adverse cardiovascular events over a median following-up of 4 years [13].

Doi T, et al. reported that CAE was independently associated with significantly increased risks of cardiac death (3-fold increase; p=0.004) and non-fatal MI (5-fold increase; p<0.001) [14].

Due to limited evidence, long-term anticoagulation therapy is typically reserved for high-risk patients, such as those with multivessel ectasia or those experiencing recurrent thrombotic events despite being on dual antiplatelet therapy. The common coexistence of CAE with obstructive lesions, coupled with the documented risk of MI in some cases, justifies the routine use of aspirin in all CAE patients [15].

Data on percutaneous coronary intervention in the context of incidental coronary aneurysms remain limited, mostly derived from small case series [16]. In acute coronary syndrome, percutaneous coronary intervention involving aneurysmal segments is associated with poor prognosis, including least procedural success, greater rates of no-re-flow and distal embolization, increased risk of stent thrombosis, need for frequent revascularization, and greater long-term mortality [17].

The aim of this study was to assess CAE prevalence among subjects who underwent coronary angiography and intervention, as well as the possible factors associated with ectasia. Anatomical distribution of vessels involved.

Study design and setting. An observational comparison analytic study was conducted in Ibn Al-Baitar and Al-Nasirya cardiac centers between February 2020 and February 2021, involving 263 patients who underwent elective and emergency coronary angiography.

Ethical approval. The Medical Ethical Committee of The Department of Medicine approved this study (no. 398 on 20-01-2019).

Coronary angiography intervention. Coronary angiography was performed based on clinical indications, such as a history of angina, prior or acute MI, or positive results from noninvasive diagnostic testing. Every patient underwent an ECG performed as a routine evaluation, and coronary angiography was performed using Philips devices in both centers, using (Seldinger) technique with the femoral or radial approach. The findings were interrupted by two senior interventional cardiologists during the procedure for every case [18][19].

Data collection and excluding criteria. Patient data were collected by using a study-specific questionnaire. Individuals with congenital or valvular heart disease as well as cardiomyopathies were excluded from the study, as these conditions are more commonly associated with congenital forms of ectasia and arterial dilatation, according to previous reports.

Statistical analysis. Data were analyzed using the Statistical Package for the Social Sciences (SPSS) version-22. Categorical variables are presented as frequencies and percentages, and the associations between them were measured using Pearson’s test. Logistic regression is a robust method for evaluating the relationship between one or more predictor variables (continuous or categorical) and the presence or absence of CAE. It estimates the odds ratio for each factor, and statistical significance is assessed through 95% CI. Continuous parametric data were compared between study groups using an independent two-tailed t-test with significant statistical p-value <0.05.

In total, 263 cases were included in this study who underwent coronary angiography, 39 patients had CAE in one or more vessels, while 224 were non-ectatic (did not have ectasia), with age (mean) of the non-ectatic group was (62.1±9) years. The age (mean) of the ectasia group was greater, since CAE was more common in the older age group. Approximately, the non-ectatic group males to female ratio was 1.52:1, whereas in the ectatic group, it was 2.55:1. The non-ectatic group included patients with diabetes mellitus (DM) type-II greater by 3-folds than in the ectatic group. Regarding smoking habits, the non-ectatic group had active smoker cases more than in the ectatic group by 3-times. The non-ectatic group had cases with positive ischemic heart disease (IHD) family history more than the ectatic group, by 3-folds. History of IHD was presented more in the non-ectatic group than the ectatic group by 4-folds. Among healthy people, hypercholesterolemia was almost 3 times more common than in patients with ectasia (table 1).

The logistic regression analysis identified several significant factors. Increased age was significantly associated with elevated ectasia rate. DM, hypertension (HTN), smoking history, and IHD positive family history were also strong and statistically significant factors. Notably, a previous history of IHD showed the strongest association, indicating that patients with prior IHD were substantially more likely to develop the ectasia (table 2).

Among the study participants, involvement of the coronary arteries was most frequently observed in the right coronary artery (RCA), which was affected in 25 patients (64.1%). The left circumflex artery was involved in 17 patients (43.6%), while the anterior descending artery (LAD) was affected in 16 patients (41%). These findings indicate that RCA involvement was the most common among the coronary vessels assessed.

In our study, CAE was more common (14.8%) than its prevalence in similar studies done across the world [20]. This high prevalence may be attributed to the elevated CAD prevalence and atherosclerosis conditions in the Middle East or may be attributed to the increased genetic predisposition to the development of CAE.

Ectatic patients were mostly over 40-years-old (65 to 70 years). CAE was predominant in males in this study. This finding is supported by previous studies that mentioned man dominance for CAE, with an M:F ratio of 2:1 [21]. However, this ratio was higher in a large study performed in Singapore (3:1), although the incidence of ectasia was less than that in this study [4]. This may be attributed to the fact that no exclusion criteria were mentioned in the study, while in our study, we mentioned valvular heart disease, congenital, and cardiomyopathy disease as exclusion criteria.

Overall, logistic regression in this study provided a structured and statistically rigorous approach to evaluate how each factor contributes to disease likelihood, highlighting the factor associated with ectasia such as prior IHD family history, HTN and DM type-II. A meta-analysis showed that DM was present in cases with CAE in percentage around 8-33% and suggested DM as a protective against the development of CAE [22], while the incidence of DM in our study was higher at 84.6%). This may be due to the high prevalence of DM type-II in middle-aged people [23]. These results are supported by previous studies in our region [24].

In this study, a significant majority of patients with CAE — 79.4%) were found to have HTN, and 76.9% were current smokers. These factors for CAD align with findings from other studies, which have also shown a strong association between HTN, smoking, and CAE [25]. A significant number (74.4%) of cases had a positive history of IHD or presented with acute angina, these results come in line with the results presented by Nyamu P, et al. [25] and Demopoulos VP, et al. [26].

These observations may introduce ectasia as a factor for IHD and sudden cardiac death due to slow flow, coronary spasm, coronary dissection, and CA thrombosis [27]. We found that approximately 89.7% of cases had hypercholesterolemia on statin therapy. Our results revealed a significant correlation between hypercholesterolemia and ectasia. Many studies have also highlighted the prevalence of hypercholesterolemia among patients with CAE, with rates reported as 63% in Singapore, 59% in Saudi Arabia [24], and 41.7% in Iran [20]. These findings, including those from our study, are consistent with those of other studies that have shown a clear association between hypercholesterolemia and the presence of CAE, showing that this lipid disorder was very common in patients with coronary ectasia. However, patients with hypertriglyceridemia showed no statistical significance in terms of CAE, which is supported by many studies [28-32].

Consistent with previous studies, the RCA was the most frequently affected vessel in our study. However, Nyamu et al. found that the LAD was the most commonly affected vessel [25]. They also observed that ectasia in the LAD typically presented as discrete, whereas the RCA showed a more diffuse pattern of ectasia, a finding also noted in Demopoulos et al.’s study [26].

This study has several limitations that should be acknowledged. First, the study was conducted in two cardiac centers only, which may restrict the generalizability of the findings to the wider population. Second, angiographic assessment was used to diagnose CAE without intravascular imaging modalities, which could provide more precise measurements of ectatic segments. In addition, some potential confounding factors, such as inflammatory markers, lipid subfractions, or genetic predispositions, were not evaluated. Finally, the relatively small sample size may have limited the power to detect weaker associations. Despite these limitations, the study provides valuable insight into the prevalence and factors of CAE in the Iraqi population.

The CAE prevalence in the two Iraqi cardiac centers was higher than the expected level in the Middle East. The distribution of common CHD factors was the most prevalent in CAE subjects. Except for an increase in triglyceride levels, there was no statistical significance in this study. Future studies should aim to include larger, multicenter cohorts to improve the generalizability of findings and to better represent different regions and populations. The use of advanced imaging techniques such as intravascular ultrasound, optical coherence tomography, or coronary computed tomography angiography is recommended to provide a more accurate assessment of CAE morphology and extent. In addition, prospective cohort studies are needed to clarify the causal relationship between identified factors and CAE development. Further research should also explore the pathophysiological mechanisms underlying CAE, including the role of inflammation, endothelial dysfunction, and genetic susceptibility. Finally, studies assessing the long-term clinical factors associated with ectasia and optimal management strategies for patients with CAE would be valuable in guiding prevention and treatment approaches.

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