Comparison of the Efficacy and Safety of Sutureless Technique Versus Conventional Surgery in the Initial Treatment of Total Anomalous Pulmonary Venous Connection: A Systematic Review and Meta‐Analysis

ABSTRACT

Total anomalous pulmonary venous connection (TAPVC) is a rare but life‐threatening congenital heart defect that requires surgical correction. The sutureless technique has been developed as an alternative to conventional repair to minimize postoperative complications. This meta‐analysis evaluates and compares the efficacy and safety of the two surgical approaches. A comprehensive literature search was conducted in PubMed, EMBASE, the Cochrane Library, and major Chinese databases for studies published between January 2010 and December 2024. Five retrospective comparative studies including a total of 1,327 patients met the inclusion criteria. Data were analyzed using RevMan version 5.4. Primary outcome measures included the incidence of postoperative pulmonary venous obstruction (PVO), reoperation due to PVO, total postoperative mortality, and late mortality. A random‐effects model was applied to all analyses to account for anticipated clinical heterogeneity. A subgroup analysis based on TAPVC anatomical type was also performed. The meta‐analysis demonstrated that the sutureless technique was associated with a significantly lower postoperative PVO rate (Odds Ratio [OR] = 0.46; 95% Confidence Interval [CI]: 0.28–0.77; p = 0.047) and a reduced reoperation rate due to PVO (OR = 0.25; 95% CI: 0.08–0.77; p = 0.049) compared with conventional surgery. Subgroup analysis indicated that the reduction in postoperative PVO was most evident among patients with infracardiac‐type TAPVC. No statistically significant differences were observed in total postoperative mortality (OR = 0.66; 95% CI: 0.35–1.24; p > 0.05) or late mortality (OR = 0.37; 95% CI: 0.13–1.06; p > 0.05). Across all outcomes, heterogeneity was low to moderate (I² < 50%). Major limitations of this study include the retrospective design of all included studies, small sample sizes for certain analyses, variability in study methodology, and possible publication bias. The sutureless technique appears to be a safe and effective alternative to conventional surgery for primary TAPVC repair. It significantly reduces postoperative PVO and the need for reoperation, with the greatest benefit observed in high‐risk subtypes such as infracardiac TAPVC. However, given that all available evidence is derived from retrospective studies of moderate quality, further large‐scale prospective investigations are required to validate these findings and assess long‐term outcomes.

Abbreviations

CBM

China Biomedical Literature Database

CI

Confidence Interval

CNKI

China National Knowledge Infrastructure

NOS

Newcastle‐Ottawa Scale

OR

Odds Ratio

PRISMA

Preferred Reporting Items For Systematic Reviews And Meta‐Analysis

PVO

Pulmonary Venous Obstruction

RCT

Randomized Controlled Trial

TAPVC

Total Anomalous Pulmonary Venous Connection

TAPVR

Total Anomalous Pulmonary Venous Return

WMD

Weighted Mean Difference

1. Introduction

Total anomalous pulmonary venous connection (TAPVC) is a rare congenital heart defect [1] in which pulmonary veins fail to connect normally to the left atrium, leading to systemic desaturation and early mortality if untreated [2]. Surgical correction remains the only definitive treatment [3], but postoperative pulmonary venous obstruction (PVO) continues to be a major cause of morbidity and mortality, with reported incidences ranging from 10% to 20% after conventional repair [4].

The sutureless technique, introduced as an alternative to conventional surgery, involves creating a wide, tension‐free anastomosis between the pulmonary venous confluence and the left atrium without directly suturing the fragile pulmonary vein tissue [5, 6]. This approach minimizes manipulation, promotes endothelial healing, and potentially reduces postoperative PVO. Recent studies have shown encouraging outcomes with the sutureless technique, especially in high‐risk subtypes such as infracardiac TAPVC [7, 8].

Although some studies have compared the efficacy and safety of the sutureless technique and traditional surgery in the treatment of TAPVC, systematic evaluations remain necessary to synthesize evolving evidence. While a similar meta‐analysis was published by Zhao et al. [6] and Thanh et al. [9] in 2022, our study incorporates more recent literature and aims to provide an updated synthesis of evidence, with a specific focus on subgroup analyses that were not previously explored. Existing studies are often limited by small sample size [10], single‐center [11, 12], and significant heterogeneity in research methods and intervention protocols [13, 14], making it challenging to draw consistent conclusions regarding the true benefits of the sutureless technique in TAPVC treatment. Despite these reported benefits, controversy remains regarding the long‐term safety and efficacy of the sutureless technique compared with traditional repair. Therefore, this meta‐analysis aims to comprehensively evaluate comparative outcomes between the two techniques, with a specific focus on postoperative PVO and related complications.

2. Methods

2.1. Sources of Literature and Retrieval Methods

This meta‐analysis was conducted and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) 2020 statement [15]. A comprehensive literature search was performed across the following electronic databases: PubMed, EMBASE, Web of Science, Cochrane Library, China National Knowledge Infrastructure (CNKI), VIP Full‐Text Database, Wanfang Database, and the Chinese Biomedical Literature Database (CBM). The inclusion of Chinese databases aimed to capture studies from regions with a high volume of cardiac surgeries and to minimize potential language and publication bias. In addition to peer‐reviewed journal articles, relevant conference proceedings, dissertations, and other scholarly materials were also screened. The search was supplemented by manual tracing of references from included studies. Both Medical Subject Headings (MeSH) and free‐text terms were used to maximize search sensitivity. The search strategy combined the following keywords and their variations: (“sutureless” OR “sutureless repair” OR “sutureless technique”) AND (“conventional surgery” OR “traditional surgery” OR “standard repair”) AND (“total anomalous pulmonary venous connection” OR “TAPVC” OR “total anomalous pulmonary venous return” OR “TAPVR”). The comprehensive search covered studies published from January 2010 to December 2024. An updated search conducted in November 2025 identified no new eligible studies. Gray literature sources (conference abstracts, dissertations, and ongoing clinical trial registries such as ClinicalTrials. gov) were screened; however, no additional eligible unpublished or ongoing studies were identified. The results of the gray literature search have been explicitly stated to ensure transparency.

2.2. Literature Inclusion and Exclusion Criteria

2.2.1. Inclusion Criteria

Study type: Retrospective or prospective cohort studies or case‐control studies comparing sutureless technique with traditional surgery in the treatment of primary TAPVC, conducted both domestically and internationally.

Study subjects: Patients diagnosed with TAPVC based on clinical criteria and confirmed by imaging methods (such as cardiac ultrasound, CT, or MRI). These patients must have met the surgical indications for primary surgical repair.

Intervention measures: The experimental group received sutureless technique treatment, while the control group underwent traditional surgical intervention.

Outcome measures: Studies must report at least one of the following outcome indicators: a) Postoperative PVO ratio; b) Reoperation rate due to PVO; c) Total postoperative mortality; d) Late postoperative mortality, etc. e) Definitions of outcomes such as “late mortality” (e.g., death after 30 days or hospital discharge) were recorded as reported by the original studies.

2.2.2. Exclusion Criteria

Studies that were not comparative cohort or case‐control studies (e.g., single‐arm case series).

Studies with incomplete data that cannot be used for analysis.

Duplicate studies, or studies with overlapping patient populations, in which case the publication with the most comprehensive data was included.

Studies focusing on reoperations or PVO repair rather than primary TAPVC correction.

Review articles.

Case reports.

2.3. Quality Assessment and Data Extraction

2.3.1. Bias Risk Assessment

Two authors (L.S. and N.D.) independently assessed the methodological quality of the included studies using the Newcastle‐Ottawa Scale (NOS), which is suitable for non‐randomized studies. The scale evaluates studies on three domains: selection of study groups, comparability of groups, and ascertainment of the outcome of interest. Scores range from 0 to 9 stars, with studies scoring ≥ 7 considered high quality. Discrepancies were resolved through discussion or by consulting a third researcher (Z.L.).

2.3.2. Literature Screening and Data Extraction

Two researchers independently screened the literature, extracted the data, and evaluated the quality of the studies. Discrepancies were resolved through discussion or by consulting a third researcher. Reference management software (EndNote) and Excel were used to manage and extract the data. If any study had incomplete data, the authors were contacted to provide the missing information. The extracted data included:

Basic information: Author, publication year, study design, number of cases, patient demographics, and TAPVC type distribution;

Intervention measures: Treatment regimen, course of treatment;

Outcome indicators: Postoperative PVO ratio, reoperation rate due to PVO, total postoperative mortality, late postoperative mortality, etc. A supplementary table (Supporting Table S1) summarizes how each included study defined key outcome variables, including PVO, criteria for reoperation, and timing definitions for total and late mortality.

2.4. Statistical Processing

Meta‐analysis was performed using RevMan 5.4 software, developed by the Cochrane Collaboration. The Odds Ratio (OR) was used as the effect indicator for dichotomous data. For continuous data, such as results from the nine‐hole nail test, motor index measurement, muscle balance tests, modified functional reach test, and T‐shirt test, the mean and standard deviation were used for analysis in RevMan 5.4. The weighted mean difference (WMD) was used as the effect indicator, and a 95% confidence interval (95% CI) was calculated.

Initially, χ² test was used to assess heterogeneity among the studies. Given the anticipated clinical and methodological diversity across the studies (e.g., variations in patient populations, surgical experience, and follow‐up duration), a random‐effects model was chosen a priori for all analyses, as it provides a more conservative estimate of the treatment effect by accounting for both within‐study and between‐study variance. Statistical heterogeneity was quantified using the I² statistic. I² values of 0%–25% represented low heterogeneity; 26%–50% moderate heterogeneity; and > 50% substantial heterogeneity. If heterogeneity remained high (e.g., I² ≥ 75%) and no clear source of heterogeneity could be identified, sensitivity analyses or subgroup analyses were planned to explore potential reasons. A subgroup analysis was performed based on the anatomical type of TAPVC (e.g., supracardiac, infracardiac) to investigate whether the treatment effect differed across these groups. To further assess publication bias, an inverted funnel plot was drawn. Visual inspection of the funnel plot's asymmetry was performed. Due to the small number of included studies (< 10), formal statistical tests for funnel plot asymmetry like Egger's test were not performed, as they have low power and can be misleading in such scenarios [16].

3. Results

3.1. Literature Search Results and Basic Information of Included Studies

The literature search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta‐Analysis (PRISMA) guidelines. A total of 993 articles were retrieved from computer database searches. After removing 116 duplicates using EndNote and an additional 158 records flagged by automation tools or for other reasons, 719 articles were retained for screening. During a preliminary review of titles and abstracts (n = 719), we excluded 314 studies that were not relevant to the comparison of surgical techniques for TAPVC. The full texts of the remaining 405 articles were sought for retrieval, of which 132 could not be obtained. The full texts of 273 articles were assessed for eligibility. Of these, 268 articles were excluded for various reasons: 149 had incomplete data for meta‐analysis, 75 did not meet the predefined inclusion criteria (e.g., were single‐arm studies or focused on reoperations), and 44 had unclear outcome indicators or definitions. Ultimately, five retrospective comparative studies were included in the analysis, involving a total of 1,327 patients [17, 18, 19, 20, 21]. The literature screening flow chart is shown in Figure 1, and the basic characteristics of the included studies are summarized in Table 1.

Figure 1.

PRISMA flow diagram of literature screening and selection. The diagram shows the systematic process of identifying, screening, and selecting studies included in the meta‐analysis. Of the 993 articles retrieved, 719 remained after duplicates were removed, 5 retrospective comparative studies (totaling 1,327 patients) were finally included in the analysis. Full‐text exclusion reasons are detailed in the Results section.

Table 1.

Basic characteristics of the literature.

Included literature	Year of publication	Sample size		Interventions		Type of study	Outcome measures	Newcastle‐Ottawa scale (NOS) score	Median age (days, range)	Emergency cases (n, %)
		C	T	C	T
Rito Lo [17]	2015	126	69	CS	ST	Retrospective cohort	①②③④	6	36 (4–85)	18 (2–52%)**
Zhang [18]	2015	98	81	CS	ST	Retrospective cohort	①②③④	5	13 (2–123)	12 (1–60%)**
Shi [19]	2017	690	78	CS	ST	Retrospective cohort	①	4	202.6 ± 41.0*	53 (7.7%)
Yamashita [20]	2013	5	7	CS	ST	Retrospective cohort	①②③④	6	93 (42–147)	NR
Qiu ZH [21]	2021	130	43	CS	ST	Retrospective cohort	③	5	90 (30–180)	16 (12%)

Note: * data represent as mean ± SD; ** estimated from raw data provided in original studies.

Abbreviations: C, Control group (Conventional Surgery); CS, conventional surgery; NR, Not Reported; ST, sutureless technique; T, Treatment group (Sutureless Technique); ①, postoperative PVO ratio; ②, reoperation rate due to PVO; ③, total postoperative mortality; ④, late postoperative mortality.

3.2. Assessment of Methodological Quality of Included Studies

All five retrospective comparative studies included in this meta‐analysis reported baseline patient characteristics. Each study provided detailed descriptions of the intervention methods, outcome measures, and specific grouping methods. Based on the Newcastle‐Ottawa Scale (NOS), the quality of the included studies ranged from 4 to 6 stars (Table 1), indicating a moderate risk of bias. To ensure clarity, abbreviations for the intervention groups were standardized across the manuscript and tables: ‘C’ denotes the control group (conventional surgery), and ‘T’ denotes the treatment group (sutureless technique). The major limitations of this meta‐analysis stem from the retrospective design of all included studies, the absence of blinding, and incomplete reporting of follow‐up in several cases. None of the studies provided detailed descriptions of blinding procedures, allocation concealment, or participant follow‐up status, including the number and reasons for withdrawals. This lack of methodological transparency introduces potential bias and reduces the internal validity of the pooled findings. The risk of bias assessment for each study is presented in Figures 2 and 3. Although funnel plots were used to evaluate potential publication bias, the small number of included studies limits the statistical power of this approach; therefore, the presence of publication bias cannot be completely excluded.

Figure 2.

Risk of bias summary (study‐level overview). Each bar represents the risk of bias across the main domains (selection, comparability, and outcome assessment) for each included study. The figure highlights moderate methodological quality overall, consistent with NOS scores ranging from 4 to 6.

Figure 3.

Risk of bias distribution (domain‐level distribution). The proportion of studies categorized as low, unclear, or high risk of bias is shown for each bias domain. Most studies were judged as moderate risk due to retrospective design and incomplete follow‐up reporting.

3.3. Meta‐Analysis Results

3.3.1. Postoperative Pulmonary Venous Obstruction (PVO) Rate

For postoperative PVO, heterogeneity was moderate (Chi² = 6.78, df = 4, p = 0.15, I² = 41%), consistent with small‐study effects and sample size limitations. The random‐effects model analysis demonstrated a significantly lower PVO rate in the sutureless group (OR 0.46, 95% CI 0.28–0.77; p = 0.047), as shown in Figure 4.

Figure 4.

Forest plot comparing postoperative pulmonary venous obstruction (PVO) between sutureless technique and conventional surgery. Using a random‐effects model, the pooled analysis shows a statistically significant reduction in postoperative PVO with the sutureless technique (OR 0.46, 95% CI 0.28–0.77, p = 0.047; I² = 41%). The plot indicates that most individual studies favor the sutureless approach, with moderate heterogeneity across studies.

3.3.2. Reoperation Due to PVO

For reoperation due to PVO, three clinical control studies were included(17, 18, 20), with a total of 386 samples. No heterogeneity was detected (Chi² = 0.09, df = 2, p = 0.96, I² = 0%). A random‐effects model analysis indicated a significantly lower reoperation rate in the sutureless group (OR 0.25, 95% CI 0.08–0.77; p = 0.049), as shown in Figure 5. To assess robustness, sensitivity analyses were conducted. For the PVO outcome, excluding the largest study [19] yielded a consistent result (OR 0.49, 95% CI 0.29–0.82). For reoperation rates, excluding the study with the smallest sample size [20], which might be prone to small‐study effects, also confirmed the findings favoring the sutureless technique (OR 0.27, 95% CI 0.08–0.93). The forest plots for these sensitivity analyses are presented in Supporting Figure S1 and Supporting Figure S2.

Figure 5.

Forest plot comparing reoperation rates due to PVO between sutureless technique and conventional surgery. The pooled odds ratio indicates a significantly lower reoperation rate in the sutureless group (OR 0.25, 95% CI 0.08–0.77, p = 0.049; I² = 0%). The consistent direction of effects across studies supports the robustness of this finding.

3.3.3. Postoperative Overall Mortality

Four clinical control studies were analyzed [17, 18, 20, 21] with 559 participants. A meta‐analysis of total postoperative mortality was conducted. The heterogeneity test showed Chi² = 1.23, df = 3, p = 0.75, I² = 0%, indicating no significant heterogeneity among the included studies. The random‐effects model analysis revealed no statistically significant difference in total postoperative mortality between the study group and the control group (OR 0.66, 95% CI 0.35–1.24; p > 0.05), as shown in Figure 6.

Figure 6.

Forest plot of total postoperative mortality for sutureless versus conventional surgery. No statistically significant difference was found between groups (OR 0.66, 95% CI 0.35–1.24, p = 0.21; I² = 0%). The low heterogeneity suggests that mortality outcomes were relatively consistent across studies.

3.3.4. Late Postoperative Mortality

The meta‐analysis of late postoperative mortality also included three clinical control studies [17, 18, 20], with a total of 348 participants. The heterogeneity test showed Chi² = 3.32, df = 2, p = 0.19, I² = 40%, indicating low to moderate heterogeneity among the studies. The random‐effects model analysis showed no statistically significant difference in late postoperative mortality between the two groups (OR 0.37, 95% CI 0.13–1.06; p > 0.05), as shown in Figure 7.

Figure 7.

Forest plot of late postoperative mortality for sutureless versus conventional surgery. The pooled analysis shows no significant difference (OR 0.37, 95% CI 0.13–1.06, p = 0.07; I² = 40%). Although the result trends toward favoring the sutureless technique, the evidence remains statistically inconclusive.

3.3.5. Subgroup Analysis by TAPVC Type

We conducted a subgroup analysis for the primary outcome of postoperative PVO based on the predominant TAPVC type reported in the studies. Due to limited data, we were only able to extract sufficient information for a comparison in infracardiac‐type TAPVC from two studies [17, 18]. The analysis, including 68 patients in the sutureless group and 95 in the conventional group, showed a significant reduction in PVO with the sutureless technique (OR 0.22, 95% CI 0.06–0.81; p = 0.02), with no heterogeneity (I² = 0%). This suggests the benefit of the sutureless technique may be more pronounced in this high‐risk patient subgroup. Detailed results are presented in Table 2. Although pooled odds ratios were used as the standardized measure of effect, inspection of raw data suggests that the sutureless technique corresponded to an absolute risk reduction of approximately 8%–12% in postoperative PVO compared with conventional surgery.

Table 2.

Subgroup Analysis of Postoperative PVO for Infracardiac TAPVC.

Study	Year	Sutureless technique (Events/Total)	Conventional surgery (Events/Total)	Odds ratio (OR)	95% CI
Rito Lo [17]	2015	2/21	6/35	0.50	0.09–2.80
Zhang [18]	2015	1/47	8/60	0.14	0.02–1.12
Total		3/68	14/95	0.22	0.06–0.81

Note: Heterogeneity: Chi² = 0.52, df=1 (p = 0.47); I² = 0%. Overall Effect: Z = 2.29 (p = 0.02). Random‐effects model used.

3.3.6. Publication Bias Analysis

Funnel plots were generated for the postoperative PVO ratio, reoperation rate due to PVO, total mortality, and late mortality of the two groups, and publication bias was assessed (Figures 8, 9, 10, 11). Funnel plots for PVO and reoperation outcomes appeared largely symmetrical, suggesting minimal publication bias. Mild asymmetry was observed for total and late mortality, likely due to the small number of included studies (< 10) and small sample sizes, which limit the interpretive value of funnel plots. Therefore, publication bias cannot be ruled out.

Figure 8.

Funnel plot for postoperative PVO ratio. The relatively symmetrical distribution of studies suggests minimal publication bias for this outcome, though small sample size limits definitive interpretation.

Figure 9.

Funnel plot for reoperation rate due to PVO. A relatively symmetrical funnel shape indicates limited evidence of publication bias; however, small‐study effects cannot be excluded.

Figure 10.

Funnel plot for total postoperative mortality. Mild asymmetry suggests potential underrepresentation of small studies reporting neutral or unfavorable results, which may indicate possible publication bias.

Figure 11.

Funnel plot for late postoperative mortality. Some asymmetry is visible, reflecting potential small‐study bias; however, the limited number of studies (< 10) restricts the interpretability of funnel plots in this context.

4. Discussion

Traditional surgical methods have long been a cornerstone in the treatment of TAPVC. The decision to opt for traditional surgery is primarily based on the patient's specific condition, including the complexity of the cardiac structure, the degree of pulmonary venous abnormality, and the patient's age and overall health [22, 23]. For example, in patients with obstructed TAPVC and significant pulmonary hypertension, traditional surgery provides an effective means to correct the blood flow path and relieve the hypertension [24]. However, traditional surgery is not without risks, particularly the development of postoperative PVO, and thus there remains a need for alternative treatment options to address the needs of different patient groups [4]. It is important to clarify that conventional surgery is frequently and successfully performed in neonates, who represent a significant portion of TAPVC patients, and is not contraindicated based on age alone [25].

The sutureless technique, as an innovative surgical technique, has several advantages over traditional methods. The key benefit of this technique is its potential to reduce postoperative complications by minimizing the use of sutures directly on the pulmonary vein orifices and optimizing the anastomosis. Some studies have reported that compared to traditional surgery, the sutureless technique can lead to lower rates of PVO [6, 9]. Moreover, the wide, tension‐free anastomosis created with a pericardial patch provides more even tension distribution compared to traditional interrupted suturing, which helps reduce the risk of suture line stricture [5].

This study included 5 retrospective comparative studies with a total of 1,327 samples, and a meta‐analysis was performed on the postoperative PVO ratio of the two groups. The results showed that the postoperative PVO ratio was significantly lower in the sutureless technique group compared to the traditional surgery group. This outcome may be closely related to the technical characteristics of the sutureless repair. The sutureless technique avoids direct suturing of the friable pulmonary vein tissue, creating a large, unobstructed pathway into the left atrium, which reduces trauma and the risk of inflammatory response and subsequent scar formation [26]. Compared with traditional surgery, sutureless techniques help maintain a smoother connection between the pulmonary veins and the left atrium, which reduces the risk of postoperative anastomotic stenosis and thrombosis, ultimately lowering the incidence of postoperative PVO. Our subgroup analysis further suggests that this benefit may be particularly significant for patients with infracardiac TAPVC, a subtype known for a higher risk of postoperative PVO. In addition, the reoperation rate due to PVO was significantly lower in the sutureless technique group compared to the traditional surgery group. This indicates that the sutureless technique may be more effective in ensuring the stability of the anastomosis. The precise and refined nature of the sutureless technique minimizes traction damage to the pulmonary vein tissue during the anastomosis construction, reducing the risk of both early and late postoperative pulmonary vein stenosis. This could be one of the primary reasons for the lower reoperation rate in the sutureless technique group [27].

Our use of random‐effects modeling for all analyses was deliberate, as clinical diversity among included studies was anticipated even where statistical heterogeneity was low. While I² values ranged from 0% to 41%, random‐effects models provide more conservative estimates that account for between‐study variability. The exact P‐values (p = 0.047 for postoperative PVO and p = 0.049 for reoperation) indicate borderline statistical significance, suggesting that results should be interpreted cautiously rather than as definitive. Sensitivity analyses excluding the largest study confirmed the robustness of findings (Supporting Figures S1 and S2). However, given the modest number of included studies and their retrospective nature, small changes in data weighting could influence significance thresholds.

Despite these benefits, our meta‐analysis found no statistically significant difference in mortality rates between the sutureless technique group and the traditional surgery group. A potential reason for this finding could be that mortality in TAPVC surgery is influenced by multiple factors beyond the surgical technique itself, such as the severity of concomitant cardiac anomalies, the presence of pulmonary hypertension, and the overall preoperative clinical status. Additionally, the relatively limited number of included studies and the short‐ to mid‐term follow‐up durations might not have captured longer‐term survival benefits.

Compared to traditional surgery, the sutureless technique offers the advantage of more accurately maintaining the connection between the pulmonary veins and the left atrium, thus reducing the risk of postoperative complications such as anastomotic stenosis, thrombosis, and PVO [28]. Additionally, the reduced reoperation rate in the sutureless technique group indicates that this technique may provide better long‐term stability for the pulmonary vein anastomosis [29].

Although the sutureless technique demonstrates favorable early outcomes, evidence regarding its long‐term effectiveness remains limited. Theoretically, late complications may still arise due to progressive fibrotic remodeling at the pulmonary venous–left atrial interface or residual hemodynamic gradients not evident immediately post‐surgery. Most available studies report follow‐up durations under 5 years, which may be insufficient to capture late stenosis or pulmonary hypertension recurrence. Therefore, continuous long‐term follow‐up and multicenter registries are needed to clarify whether the early benefits of the sutureless approach persist beyond the medium term.

Nevertheless, it is important to acknowledge several limitations in our meta‐analysis. First, it is important to interpret our findings in the context of the evidence quality. All five included studies were retrospective cohorts with Newcastle–Ottawa Scale scores ranging from 4 to 6, indicating moderate to low methodological quality. None met the predefined threshold for high‐quality evidence (≥ 7). Consequently, inherent limitations such as selection bias, lack of blinding, and incomplete follow‐up reporting may have influenced the pooled results. These factors reduce the internal validity of the meta‐analysis and limit the generalizability of our conclusions. Therefore, the overall strength of recommendation for the sutureless technique should be considered moderate at best, pending confirmation by future prospective or randomized trials. Second, heterogeneity among the included studies (e.g., patient selection, surgical experience, and follow‐up duration) may affect the generalizability of our conclusions. Although we employed a random‐effects model to account for heterogeneity, differences in study design and patient populations might still have influenced the pooled estimates. Additionally, heterogeneity in outcome definitions across studies likely introduced variability in pooled estimates. In particular, the threshold for defining PVO and the timeframes for ‘late mortality’ varied among included studies (Supporting Table S1). Nonetheless, definitional inconsistency may attenuate the precision of effect estimates and should be standardized in future studies. Third, the definition of key outcomes like “late mortality” may have varied across studies, contributing to unmeasured heterogeneity. For instance, some studies defined it as post‐discharge mortality, while others used a 30‐day cutoff. Fourth, subgroup analyses for supracardiac, cardiac, and mixed TAPVC were not performed because the majority of included studies did not provide disaggregated data by anatomical subtype. Only two studies reported detailed data for infracardiac TAPVC, which allowed a limited subgroup meta‐analysis. Accordingly, the observed pronounced benefit of the sutureless technique in infracardiac cases should be interpreted cautiously due to the small sample size and incomplete data for other subtypes. Fifth, a total of 132 full‐text articles could not be obtained, primarily due to restricted access to conference proceedings, unpublished dissertations, or non‐English publications not indexed in accessible databases. While titles and abstracts suggested minimal relevance to comparative TAPVC surgery, the exclusion of these studies may introduce publication or selection bias. This limitation is acknowledged as a potential source of bias affecting comprehensiveness.

Furthermore, while we assessed publication bias, its potential impact on our conclusions should be considered. Because all included studies were retrospective and involved relatively small sample sizes, the results are subject to confounding and potential selection bias. These design limitations constrain the ability to establish causality and limit the strength of the conclusions drawn from this meta‐analysis. Larger multicenter registries and prospective, high‐quality randomized controlled trials (RCTs) could minimize these biases and offer more definitive evidence regarding the comparative benefits of sutureless versus traditional surgical approaches.

In light of these considerations, future research should prioritize conducting well‐designed RCTs that include standardized patient selection criteria, uniform definitions of postoperative outcomes, and long‐term follow‐up. These trials would help validate the benefits of the sutureless technique observed in this meta‐analysis and further elucidate its impact on long‐term mortality, thereby guiding clinicians in selecting the most effective surgical strategy for patients with TAPVC.

5. Conclusion

This systematic review and meta‐analysis provides an updated synthesis of comparative evidence on the sutureless technique versus conventional surgery for primary TAPVC repair. The results suggest that the sutureless approach significantly reduces postoperative pulmonary venous obstruction and the need for reoperation, particularly in high‐risk infracardiac TAPVC. These findings highlight the clinical importance of continued refinement of surgical methods aimed at minimizing postoperative complications and improving survival outcomes in this vulnerable pediatric population. Nevertheless, all available evidence is derived from retrospective cohort studies with moderate methodological quality, and the long‐term durability of the sutureless technique remains uncertain. Large, prospective, multicenter trials with standardized outcome definitions and extended follow‐up are required to confirm these early advantages and fully determine the impact of this technique on long‐term prognosis and quality of life.

Author Contributions

L.S., N.D., H.L., H.Y., and J.Z. conducted the literature search. L.S., G.Z., and Z.L. screened and evaluated the identified papers. L.S., N.D., and Z.L. performed data extraction. L.S., G.Z., and Z.L. prepared the initial manuscript. All authors approved the final manuscript as submitted and agreed to be accountable for all aspects of the work.

Funding

The authors received no specific funding for this work.

Conflicts of Interest

The authors declare no conflicts of interest.

Supporting information

Supporting Figure S1: Sensitivity analysis forest plot for postoperative PVO (excluding Shi et al., 2017). This forest plot demonstrates that even after excluding the largest study, the sutureless technique remains associated with a statistically significant reduction in PVO (OR 0.49, 95% CI 0.29–0.82), confirming the robustness of the primary analysis.

Supporting Figure S2: Sensitivity analysis forest plot for reoperation due to PVO (excluding Yamashita et al., 2013). This supplementary plot confirms that the reduction in reoperation rates remains significant favoring the sutureless technique (OR 0.27, 95% CI 0.08–0.93) after excluding the study with the smallest sample size.

Supplementary Table S1: Definitions of Outcome Measures Used in Included Studies.

Shen L, Ding N, Liu H, Yi H, Zhang J, Zhao G, Li Z, “Comparison of the Efficacy and Safety of Sutureless Technique versus Conventional Surgery in the Initial Treatment of Total Anomalous Pulmonary Venous Connection: A Systematic Review and Meta‐Analysis,” Pulmonary Circulation 16 (2026): 1‐11, 10.1002/pul2.70236.

Data Availability Statement

The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.