PM1030: Appropriateness of Echocardiograms and Resource Utilization in Outpatient Management of Small Muscular Ventricular Septal Defects

Background: Isolated small muscular ventricular septal defects (smVSD) are hemodynamically insignificant and have a high rate of spontaneous closure. In the Appropriate Use Criteria (AUC) document, transthoracic echocardiogram (TTE) for routine surveillance at 1-2 years in an asymptomatic child with a smVSD is rated Rarely Appropriate, while surveillance at 3-5 years is rated Appropriate. The purpose of this study was to assess the appropriateness of TTEs performed in patients with smVSD, and to characterize outpatient resource utilization since their initial diagnosis.

Methods: The AUC have been integrated within our electronic ordering system since May 2020. Patients who had a TTE for a smVSD between May 2020-April 2022 were included. The AUC indication (chosen by the provider) and its corresponding rating was retrieved from the electronic health records. Patient age, physician experience, total number of clinic visits, electrocardiograms (ECG), TTEs since diagnosis, discharge practices and outcomes were reviewed. Charge data was obtained from our financial department (Table 1). Each patient’s total charge was calculated by summation of initial clinic visit consultation, ECG and complete TTE, with optimal charges for smVSD being $3751 for initial evaluation.

Results: TTEs were ordered using AUCs in 131 patients (71 female) by 32 providers. Of the 131 TTEs, 62 were Rarely appropriate and 69 Appropriate. Patients who had TTEs for Rarely Appropriate indication were significantly younger than those who had it for Appropriate indication (mean age 2.9±2.7 years vs 9.1±5.4, p< 0.0001). Median age at diagnosis was 1 month (IQR 0-24 months). The number of clinic visits, ECGs, TTEs and charges related to these during a median outpatient follow-up of 3.4 years (IQR 1.8-6.4 years) is shown in Table 2. After excluding the optimal charges, there was an overall excess utilization of $532,459. At their most recent visit, 57% (n=75) were recommended to continue follow-up with cardiology and 43% (n=56) were discharged. The median age at discharge was 30 months (IQR 20-59 months). Of these patients, 76% (n=43) were discharged after documenting closure of the smVSD by TTE and 24% (n=13) were discharged with smVSD. These 13 patients had been followed for a median of 4 years (IQR 3-5.16 years) at the time of discharge and 84% were discharged by providers with > 10-year experience. No adverse outcomes including arrhythmias or endocarditis were recorded in any patient.

Conclusion: There is wide practice variation in resource utilization and discharge practices in patients with smVSD with half the TTEs for surveillance ordered for Rarely Appropriate indication. Given the natural history of smVSDs and no adverse outcomes noted during the follow-up, the utility of ECG and TTE (including Appropriate indication) during follow-up should be questioned. Instead, a more conservative approach with clinic visits limited to auscultation or discharge should be considered.