The present retrospective study included a cohort of 102 patients who were diagnosed with AAOCA and whose data were collected from April 2003 to July 2022 at Beijing Anzhen Hospital, Capital Medical University. Relevant clinical data, including essential demographic information such as sex and age; blood pressure measurements (systolic and diastolic); pulse rates; occurrence of sudden death outside the hospital setting; in-hospital events, including syncope, heart failure, myocardial infarction, and mortality rates; utilization of adjunctive cardiac support devices such as extracorporeal membrane oxygenation (ECMO) or intra-aortic balloon pump (IABP); and imaging research findings, including echocardiography (ECHO), coronary angiography (CAG), and coronary computed tomography angiography (CCTA), were extracted from the hospital database.

In this study, only patients with AAOCA were included while patients with congenital heart diseases, such as atrial or septal defects and patent ductus arteriosus, were excluded. ECHO was performed to assess the ejection fraction (EF) and left ventricular end-diastolic diameter (LVEDD) before and after surgery. The AAOCA patients were categorized into two groups: anomalous left coronary artery from the pulmonary artery (ALCAPA) patients and non-ALCAPA patients. The pertinent information on the two groups of patients was collected, including major clinical manifestation data such as syncope, heart failure, myocardial infarction, and incidence of hospital death, as well as diagnostic methods such as ECHO, CCTA, and CAG. Comparisons of EF and LVEDD on ECHO were conducted before and after surgery for the two groups. Additionally, based on the symptoms of the AAOCA patients, they were categorized into two other groups: symptomatic or asymptomatic. Comparisons between these two groups were made in terms of clinical manifestation data. Some data could not be obtained due to limitations in the database system.

The ECHO procedure was performed using a Philips IE33 (Best, Eindhoven Metropolitan Area, Netherlands), EPIC 7C color Doppler ultrasound diagnostic instrument equipped with an S5-1 probe operating at a frequency range of 1.5–3.5 MHz. Cardiac morphology and valve regurgitation were comprehensively assessed, encompassing measurements of EF and LVEDD recorded preoperatively and postoperatively.

The Siemens Somation Definition Flash dual-source computed tomography (CT) scanner was used for CCTA. For adult patients, the examination encompassed the region from 10 mm below the tracheal bifurcation to the level of the diaphragm, whereas for pediatric patients, it extended from the chest entrance to the diaphragmatic level. Prospective electrocardiographic gating technology was used for image acquisition. The nonionic contrast agents Euro Naipaike (350 mg I/mL) or Weishi Paike (320 mg I/mL) were intravenously administered at the elbow via injection. The scan was triggered by automatic tracking technology synchronized with the administration of the contrast agent.

CAG procedures were conducted using a standard technique to administer coronary contrast agents, followed by the completion of angiography and simultaneous image recording.

In our institution, surgeons consistently apply personalized surgical techniques with favorable outcomes. The choice of surgical technique was left to the discretion of the surgeon based on the individual anatomy and clinical status.

Statistical analyses were conducted using the SPSS 20 software (SPSS, Chicago, IL, USA). The normality test was performed using the Kolmogorov-Smirnov test, and the results demonstrated that the data follows a normal distribution. Quantitative variables are reported as the mean $\pm$ standard deviation, whereas categorical variables are presented as percentages. Student’s paired or unpaired t-tests and nonparametric ANOVA (Mann-Whitney test) were performed to determine the differences in continuous variables between groups. The differences between dichotomous variables were determined by the $\chi$² test or Fisher’s exact test when appropriate. All differences between groups were considered to be statistically significant at p 0.05.

Between April 2003 and July 2022, 102 patients were diagnosed with AAOCA, including 49 males (48%) and 53 females (52%). Among these cases, 81 cases originated from the pulmonary artery (76 with involvement of the left coronary artery, four with involvement of the right coronary artery, and one with involvement of both coronary arteries), 12 cases with the right coronary artery (RCA) arising from the left sinus, eight cases from the left coronary artery arising from the right sinus, and one case involving an aberrant connection between the left and right coronary arteries. The mean age at diagnosis was 9.39 $\pm$ 14.28 years (range: 28 days–61 years; median: two years). Adults accounted for about 14.7% of all cases, while the rest of the study subjects were minors. The syncope rate among these patients was estimated to be about 7.8% (8/94), whereas the heart failure rate was 50.9% (52/102). Myocardial infarction occurred at a rate of about 5.9% (6/101), whereas sudden death rate was close to 2% (2/100). Additionally, ventricular aneurysms were detected in about 6.8% of patients (7/102), whereas asymptomatic patients accounted for about 38.2% (39/102) (Table 1).

Of the total 102 cases examined, data on EF and LVEDD analysis were accessible for 80 cases in the hospital database (Table 4). After surgery, the LVEDD decreased significantly relative to the preoperative level (p 0.001). However, there was no statistical difference in EF between pre-surgery and post-surgery (p = 0.374).

Based on the distribution of case numbers, the patients were classified into two groups: the ALCAPA group (74.5%) and the non-ALCAPA group (25.5%). The subsequent data were attributed to this discrepancy.

Within the patient cohort examined in this study, a slightly greater proportion of female individuals than male individuals were observed. Additionally, most of the included patients in the sample were pediatric patients. The prevailing clinical presentations included heart failure, syncope episodes, myocardial infarctions, ventricular aneurysms, and cases of SCD, with most patients exhibiting one to several of these clinical presentations. Heart failure was the most commonly encountered syndrome among all cases. A subgroup of asymptomatic individuals (38.2%) did not manifest any of the aforementioned syndromes but instead reported atypical symptoms such as fever, dyspnea, or chest pain. These unique cases were sporadically identified in local healthcare facilities.

In terms of the diagnostic methods used, ECHO was the most widely used noninvasive and cost-effective technique without the use of radiation. In this study, children constituted about 85.3% of the sample population, highlighting the advantages of ECHO for the diagnosis of pediatric cases. A study has reported that AAOCA can be reliably identified with intramural courses via ECHO [3]. Consequently, the proportion of ECHO diagnoses was also relatively high in this context. CCTA, as an alternative noninvasive modality, shows superior applicability (50%). These two primary approaches are commonly and routinely used because of their noninvasive characteristics, particularly when dealing with pediatric patients. Therefore, they serve as primary diagnostic methods that effectively optimize medical resource utilization.

Most patients (63.7%) could be diagnosed using a single method, whereas 34.3% required two methods for diagnosis. Noninvasive techniques are extensively used in clinical practice because of their convenience and cost-effectiveness. ECHO provides a convenient and cost-effective diagnostic approach; however, it cannot detect myocardial infarction [16]. Hence, there is a consistent need for supplementary diagnostic modalities. Intravascular ultrasound (IVUS), through simulated methodologies, facilitates the reliable assessment of myocardial infarction [17]. However, its high cost restricts its routine application in China. In this study, CCTA and CAG were integrated with other diagnostic approaches to perform accurate diagnosis.

In the general population, the prevalence of ALCAPA is about 0.021% [18]. Within our cohort of 102 patients, ALCAPA accounted for about 74.5%, which was similar to the findings of previous studies. The prevalence of heart failure was about 63.2%. Considerable differences were found in the incidence of syncope and heart failure among ALCAPA patients; The incidence of syncope was low, while the incidence of heart failure was high. These findings suggested that patients with ALCAPA face a greater risk of developing heart failure than experiencing syncope. Because the left coronary artery arises from the pulmonary artery instead of the aorta. After birth, as pulmonary artery pressure drops, the left coronary artery receives deoxygenated blood, leading to myocardial ischemia. This impairs left ventricular function, causing progressive heart muscle damage and eventual heart failure. Syncope in ALCAPA is less common and may arise from acute ischemia-induced arrhythmias or sudden drops in cardiac output. The syncope risk here likely stems from secondary arrhythmias.

In this study, 38.2% of the total population consisted of asymptomatic patients. The incidence of coronary anomalies with an interarterial course was significantly greater in asymptomatic patients (30.8%) than in symptomatic patients (4.8%), suggesting a greater prevalence among those without symptoms.

Regarding surgical techniques, specific recommendations are available for each approach, with an emphasis on their distinctive characteristics [12]. Although the coronary “unroofing” technique is commonly used for AAOCA [19], our findings indicated limited application of this technique due to the presence of these symptom-free individuals. Instead, this study cohort predominantly underwent procedures such as coronary artery ostioplasty and pedicled left coronary artery transplantation as patients candidates for simpler surgical techniques like unroofing were often treated in local hospitals and therefore nor referred to our institution for treatment and inclusion in the present analysis. Surgeries such as coronary “unroofing” were feasible; however, more complex procedures were necessary under specific circumstances.

In this study, coronary artery ostioplasty was performed in 66 patients (64.7%), making it the most frequently used surgical approach for ALCAPA because it can address all anatomical issues directly. However, this procedure presents challenges requiring expertise and specialized nursing care [20, 21].

After surgical intervention, the LVEDD decreased significantly compared to the baseline condition before surgery; however, no substantial change in the EF was noted after surgery. This indicated that significant changes in post-surgery cardiac function was combined with a positive outcome resulting from surgical intervention, indicating significant changes in post-surgery cardiac function, a positive outcome resulting from surgical intervention on cardiac functionality.

Before and after surgery, asymptomatic patients consistently presented higher EF values than symptomatic patients. However, no significant differences in the LVEDD were observed between the two groups. A retrospective study conducted over 20 years in France revealed that about 25% of asymptomatic patients remain asymptomatic, 65% of patients are at risk of coronary artery abnormalities, and 38% of patients experience interatrial and/or intramural courses of coronary artery anomalies [16]. Considering the risks associated with interatrial abnormalities such as SCD and severe events, timely diagnosis and surgical intervention are crucial for these individuals. Hence, unlike symptomatic patients, asymptomatic individuals do not exhibit specific syndromes but are more prone to interatrial and/or intramural courses of coronary artery anomalies. Appropriate surgical interventions need to be implemented to mitigate the risk of SCD.