Though ASD2 closure via device placement has become the first choice of most ASD2 repairs, surgical ASD2 repair is still performed in some circumstances [3]. Despite low morbidity and low mortality in surgical closure of ASD2 [3, 4], current North American guidelines recommend lifelong intermittent (every 2 to 5 years) TTE even in patients with mild or no sequelae [6, 7]. In this preliminary analysis evaluating the utility of follow-up TTE in an uncomplicated cohort of patients who had undergone ASD2 surgical repair, no significant abnormalities were noted on follow-up TTE. No clinical changes were made based on follow-up TTE > 6 months after surgical repair.

Surgical ASD2 closure is relatively safe, with estimated mortality < 0.3% [10]. Major complications after surgical ASD2 repair are also relatively low, though minor complications have been reported to range from 20% to 80% [11, 12]. Many of the cardiac complications noted after ASD2 such as residual shunts, pericardial effusions, and arrhythmias are noted in hospital or during the early follow-up period [11, 12]. Because of these issues and in the absence of high-quality evidence, routine surveillance within a year following surgical ASD2 closure in an asymptomatic patient with no or mild sequelae is recommended, scoring 9/9 in consensus national guidelines in North America [6, 7].

The long-term outcomes after surgical ASD2 repair are usually good, with a low incidence of complications [4, 5, 8, 9, 13, 14]. The main long-term cardiac concerns related to surgical ASD2 repair may include issues such as arrhythmias, heart failure, and pulmonary hypertension. However, those patients who develop late complications after surgical ASD2 closure can usually be identified as being high risk either preoperatively or in the first 6–12 months postoperatively. Older age at repair, male sex, presence of peri-operative arrhythmias, peri-operative heart failure, and higher peri-operative mean pulmonary artery pressures have been documented to be risk factors for late complications in this cohort of patients [5, 8, 14,15,16].

The results of this study are essentially consistent with the previous publications. In a cohort of patients with ASD2 and minimal to no risk factors, surgical repair had excellent short-, medium-, and long-term outcomes. No patient had any evidence of documented arrhythmias, pulmonary hypertension, or heart failure. A small percentage of patients did have qualitatively mild right-sided dilation, but in the absence of objective measurements, no conclusion can be drawn. One study showed that despite right-sided dilation, the exercise capacity and incidence of arrhythmias was not different from those of patients who did not have right-sided dilation after surgical ASD2 repair [4]. Furthermore, since the ASD2 was repaired, one may assume that further right-sided dilation would no longer occur or would even potentially regress.

These data, in conjunction with previous publications, call into question the utility of lifelong TTE in patients post-ASD2 repair with no complications. The data are also consistent with the European guidelines for follow-up of patients undergoing surgical ASD2 repair [17]. The European guidelines state “Patients repaired at age < 25 years without relevant sequelae or residua (no residual shunt, normal pulmonary artery pressures, normal right ventricle, no arrhythmias) do not require regular follow-up, though families should be made aware of the occurrence of late arrhythmias”. Along with the previously cited publications, these data support the European guidelines for follow-up indications in patients with ASD2 versus the lifelong TTE recommendations from the North American guidelines. It may be reasonable to follow these patients for a set period of time with TTE, but after this period, then clinical follow-up may be all that is needed unless other concerns arise. This study used a 6-month TTE as a starting point marker for inclusion in the study to increase the study population evaluated, but the time interval proposed could be 1 or even 5 years after repair before stopping routine TTE follow-up. Assuming that an ASD2 is repaired at 5 years of life and assuming an average life span of 80 years, obtaining a TTE every 2–5 years could mean up to approximately 15–35 extra TTE over the patient’s life. Regardless of the time period chosen, it is unlikely that lifelong is the most cost-efficient time period to choose for follow-up TTE. In addition to the lack of cost efficiency, there may be other unintended consequences of lifelong TTE evaluations such as scheduling and transportation burden for the patient, persistent patient apprehension, and the risk of identifying incidental but clinically irrelevant findings, prompting further unneeded investigations. In this study, the follow-up TTE > 6 months after repair did not change medical management.

This study has multiple limitations. It is a single-center retrospective study with all the inherent limitations of such a design. The sample size was small despite the study collecting data over a 25-year period. The patient population was relatively homogeneous, with a strong pediatric age predilection. This may limit the generalizability of these results to patients who had their ASD2 repaired as adults. Cardiac chamber dilation and right ventricular function was graded qualitatively versus quantitatively. The longest follow-up time evaluated in this uncomplicated cohort was 19 years, so no specific comment can be made beyond that time frame. A third of patients were lost to follow-up; however, if there were any subsequent complications noted, the patients who were lost to follow-up would likely have been referred back to our surgical center.