Percutaneous patent ductus arteriosus (PDA) closure has become the preferred therapeutic alternative since its introduction more than three decades ago, where it is also recommended by the American Heart Association/American College of Cardiology (AHA/ACC) and the European Society of Cardiology (ESC). Even though the occluder and device delivery systems have been modified throughout the years, fluoroscopy has been utilized as the gold standard for guidance modality (1, 2). With the advancement of technology, it is now feasible to be performed with limited fluoroscopic exposure. However, the detrimental effects of radiation should not be overlooked, especially for both pediatric patients and interventional cardiologists (3, 4). Pediatric patients are more sensitive toward radiation when compared to adult patients, and they have a longer life expectancy, increasing the chances of lifetime attributable risks of radiation (5). Interventional cardiologists are repeatedly exposed to radiation, thus accumulating the risks of radiation (6). Since Ewert et al. reported the first successful transcatheter closure of atrial septal defect (ASD) under transesophageal echocardiographic (TEE) guidance, many centers explored transcatheter procedures without fluoroscopy, such as ours (7). Our center has been routinely performing transcatheter closure under echocardiographic guidance in 220 patients with ASD or ventricular septal defects (VSDs) with satisfactory outcomes (8). Therefore, this single-center study is aimed to show the feasibility and safety of percutaneous PDA closure under echocardiography-only guidance during our 1-year experience.

This study included 60 patients in total, where 30 patients were allocated to the echocardiography (test) group and 30 patients were allocated to the fluoroscopy (control) group. The summarized baseline characteristics of subjects and the approaches used, time taken for the procedures, crossing catheter, and devices used can be seen in Table 1.

Transcatheter closure has become the main approach for most PDA closures as it has lower complications and shorter hospital stay when compared to the surgical approach (1, 9). The 2018 AHA/ACC and the 2020 ESC guidelines for the management of congenital heart disease recommend transcatheter closure for all PDAs with evidence of LV volume overload regardless of symptoms, except in patients with Eisenmenger physiology, lower limb desaturation on exercise, PA systolic pressure greater than two-thirds of systemic systolic pressure or PVR greater than two-thirds of systemic vascular resistance adults (10, 11). For the last four decades, transcatheter PDA closure under fluoroscopy guidance has been the most popular choice due to its convenience as it can localize the wire and device accurately (12). Since the success of the first echocardiography-guided balloon atrial septostomy, which was performed by Rashkind in 1966 (13), many cardiologists have been experimenting with using echocardiography as guidance for many procedures, such as PDA closure (8, 14).

The frequent use of fluoroscopy may cause long-term side effects, depending on the dosage and duration of radiation exposure. In addition, the complexity of a procedure also adds to the duration of exposure, as in transcatheter PDA closure (15). Prolonged radiation not only harms pediatric patients who are more sensitive to radiation than adults (5), but it is also a risk to interventionists, especially those who routinely perform these procedures. While the advancement of technology allows for minimal fluoroscopic exposure through non-ionic contrast, the accumulated exposure on interventionists should not be overlooked (6), where side effects may show as late as the 70–90 s (16). Studies have shown that radiation increases the risks of skin injuries, cataracts, hair loss, and neoplasms (17). A study by Roguin et al. reported 44 interventional cardiologists with brain and neck cancer on their left side as it is exposed to more radiation than the right (18, 19).

In this study, we compared the time taken for PDA closure procedures using fluoroscopy and echocardiography. The median procedural time of using both antegrade and retrograde approaches for the test and control groups was insignificant (p = 0.575). The retrograde approach had a shorter procedural time in comparison to the antegrade approach where the catheter needs more manipulation to be directed into the right ventricle and PA to reach the PDA (see Figures 2C,D). However, the retrograde approach is limited to patients with low body weight or large PDA since complications might occur through arterial access, such as thrombosis at the access site. Regardless of the approach, the difference in procedural time between the echocardiography group and the fluoroscopy group was insignificant (p = 0.09). These results mean that using only echocardiography did not compromise procedural time.

Binobaidan et al. (12), Cao et al. (20), and Ye et al. (21) showed success rates of 100% in PDA closure, while only Zhang et al. (22) showed a success rate of 97.1%. These results were similar to our study in which all the procedures were successful in both echocardiography and fluoroscopy groups. Most studies showed no residual shunt and severe complications after 1 month to 2 years of follow-up (12, 20–22). Pan et al. had 8 cases of small residual shunts in 24 h but resolved afterward (6). The minor complications in these studies include device embolization, acute occluder dislodgement, and small residual shunts (6, 12, 20–22). In our study, there were no complications following echocardiography-guided PDA closures with most of the patients only experiencing residual shunts, which disappeared during follow-up. However, one fluoroscopy-guided procedure resulted in moderate tricuspid regurgitation with a thrombus in the tricuspid valve. This may be due to variable confounding factors, such as the complexity of the PDA, operator experience, or the length of the procedure, which may contribute to the complications despite better visualization in the fluoroscopy group. These results showed that the echocardiography-guided procedure is not inferior to the fluoroscopy-guided procedure.

Based on pre-catheterization data, TTE or TEE showed similarities in assessing the defect size. Shyu et al. showed that TEE provided greater sensitivity to TTE in confirming PDA size (97 vs. 42%) (23). The selection of devices in 38 subjects is based on the size of the PDA. The addition of 2–4 mm from the diameter of the smallest PDA was done in device selection, but the device size would be twice the size of the PDA if it presents with pulmonary hypertension (24). Devices, such as Amplatzer Duct Occluder (ADO II) and Multifunctional (MF) Occluder, could be performed both antegradely and retrogradely. However, ADO II could only be used in patients with small PDAs. MF Occluder is now a better choice since it could be used on a large size PDA with a smaller delivery sheath. In our center, the post-procedural residual shunt is commonly found when using MF Occluder, which disappeared within 24–48 h, possibly due to the soft nature of the device. We recommend choosing devices according to the type and size of the PDA, availability, and convenience of the operators (1).

In comparison to fluoroscopic guidance, the largest hurdle of echocardiography-guided closure is to track the guidewire, catheter, and delivery sheath in the two-dimensional echocardiographic view plane, which is related to safety and procedural time. Conventional intervention techniques emphasize simplicity to determine the catheter location as fluoroscopy detects it through projection. A vast understanding of cardiac anatomy and physiology, along with the utilization of the appropriate guidewire, catheter, delivery sheath, and the positioning of the ultrasound probe, would exceedingly increase accuracy. Interventionists with insufficient experience should go for the standard procedure. Future efforts should be directed toward pre-procedural selection criteria for echocardiography-guided transcatheter PDA closure with devices based on the PDA size and surrounding structures.

The small number of subjects is an unavoidable limitation as this is the first pilot study of echocardiography-guided PDA closure to be conducted in Indonesia. The procedures were conducted by different operators, which may affect results concerning procedural times and complications as the procedures were highly dependent on the operators. Therefore, we recommend further studies with more subjects and skilled operators to validate the feasibility and safety of echocardiography-guided PDA closure.

Echocardiography-guided PDA closure is non-inferior, even with a limited window view when compared to using fluoroscopy. The procedural time for echocardiography-guided PDA closure was also not significantly different from fluoroscopy-guided PDA closure, which means that using only echocardiography did not compromise procedural time. However, as this is a new technique, this method is especially operator dependent and requires an experienced team for it to be performed successfully. Unfortunately, it would still require years for this method to be widely used.

The original contributions presented in the study are included in the article/supplementary material, further inquiries can be directed to the corresponding author.

The studies involving human participants were reviewed and approved by the Research Ethics Committee of National Cardiovascular Center Harapan Kita. Written informed consent to participate in this study was provided by the participants’ legal guardian/next of kin.

SS conceived the original idea of the manuscript. SS, RP, BP, YK, OLe, AS, IA, PR, AR, GH, and OLi contributed in collecting data and writing the main text of the manuscript. BM, CC, and MS performed statistical analyses and also helped in writing the manuscript. All authors discussed and agreed with the idea of the manuscript and accepted the proofread manuscript.

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.