Validation of administrative claims to identify ultrasound enhancing agent use

BACKGROUND

Ultrasound enhancing agents (UEAs) are an invaluable adjunct to stress and transthoracic echocardiography (STE) to improve left ventricular visualization. Despite multiple single center studies evaluating UEA use, investigation into the rates, sources of variation, and outcomes of UEA use on a national level in the United States (US) has been limited by lack of validation of UEA codes for claims analyses.

METHODS

We conducted a retrospective cross-sectional study, 2019-2022, using linked multicenter electronic medical record (EMR) data from > 30 health systems linked to all-payor claims data representing > 90% of the US population. Individuals receiving STE in both EMR and claims data on the same day during the study window were included. UEA receipt as identified by presence of a Current Procedural Terminology (CPT) or National Drug Code (NDC) for UEA use within 1-day of the index STE event. We evaluated the performance of claims to identify UEA use, using EMR data as the gold standard, stratified by inpatient and outpatient status.

RESULTS

Amongst 54,525 individuals receiving STE in both EMR and claims data, 12,853 (23.6%) had a UEA claim in EMR, 10,461 (19.2%) had a UEA claim in claims, and 9140 (16.8%) had a UEA claim in both within the 1-day window. The sensitivity, specificity, accuracy, positive, and negative predictive values for UEA claims were 71.1%, 96.8%, 90.8%, 87.4%. and 91.6% respectively. However, amongst inpatients, the sensitivity of UEA claims was substantially lower (6.8%) compared to outpatients (79.7%).

CONCLUSIONS

While the overall accuracy of claims to identify UEA use was high, there was substantial under-capture of UEA use by claims amongst inpatients. These results call into question published rates of UEA use amongst inpatients in studies using administrative claims, and highlight ongoing need to improve inpatient coding for UEA use.

Anaphylaxis to Lumason Contrast Agent in Echocardiography after Immune Sensitization: A Case Report and Literature Review

With the continued evolution of echocardiography techniques, novel contrast agents have been introduced to aid in evaluating cardiac structure and function. Lumason is an FDA-approved ultrasound-enhancing agent made of Sulfur hexafluoride lipid-type A microspheres. We report a case of Lumason-induced immune sensitization and subsequent anaphylaxis on re-exposure in a middle-aged male patient presenting with symptoms concerning for a cerebrovascular accident. The patient was successfully treated with steroids and antihistamines. Providers, including physicians, echocardiography technicians, and mid-level providers should be aware of and be prepared to respond to the possibility of anaphylaxis to contrast-enhancing agents used in echocardiography.

Echocardiography in the time of Covid-19: Ultrasound enhancing agents save time and augment diagnostic information

BACKGROUND

There are currently no clear guidelines regarding the use of ultrasound enhancing agents (UEAs) with transthoracic echocardiography (TTE) for patients hospitalized with Covid-19. We investigated whether the performance of TTE with UEAs provides more diagnostic information and allows for shorter acquisition time compared to unenhanced TTE imaging in this patient population.

METHODS

We analyzed the TTEs of 107 hospitalized Covid-19 patients between April and June 2020 who were administered UEAs (Definity®, Lantheus). The time to acquire images with and without UEAs was calculated. A level III echocardiographer determined if new, clinically significant findings were visualized with the addition of UEAs.

RESULTS

There was a mean of 11.84±3.59 UEA cineloops/study vs 20.74±8.10 non-UEA cineloops/study (p < 0.0001). Mean time to acquire UEA cineloop images was 72.28±28.18 s/study compared to 188.07±86.04 s/study for non-UEA cineloop images (p < 0.0001). Forty-eight patients (45%) had at least one new finding on UEA imaging, with a total of 62 new findings seen. New information gained with UEAs was more likely to be found in patients with acute respiratory distress syndrome (21 vs 9, p < 0.001) and in those on mechanical ventilation (21 vs 15, p = 0.046).

CONCLUSIONS

TTE with UEAs required less time and fewer cineloop images compared to non-UEA imaging in patients hospitalized with Covid-19. Additionally, Covid-19 patients with severe respiratory disease benefited most with regard to new diagnostic information. Health care personnel should consider early use of UEAs in select hospitalized Covid-19 patients in order to reduce exposure and optimize diagnostic yield.

Identification of Need for Ultrasound Enhancing Agent Study (the IN-USE Study)

BACKGROUND

Ultrasound enhancing agents (UEAs) are routinely used to improve transthoracic echocardiographic (TTE) image quality, yet anticipation of UEA need is a barrier to their use.

METHODS

Structured report data from 171,509 consecutive TTE studies in 97,515 patients who underwent TTE imaging from January 26, 2000, to September 20, 2018, were analyzed. Trends in UEA use and suboptimal image quality were examined. Among outpatients (92,291 TTE examinations, n = 56,479), the data set was randomly split into a 75% derivation sample and a 25% validation sample. Logistic regression was used to model the composite of either UEA receipt or suboptimal image quality (two or more nonvisualized segments) using only variables available at the start of the TTE examination. Model performance was tested in the validation sample.

RESULTS

A total of 4,444 TTE examinations (2.6%) in 3,827 patients (3.9%) involved UEAs, and 28,468 TTE examinations (16.6%) in 21,994 patients (22.5%) were suboptimal. UEA use increased over the observation period. Among TTE studies with suboptimal image quality, UEA use was lower in women (P < .0001). Among outpatients referred for TTE imaging, older age, greater weight, and higher heart rate best predicted UEA use or suboptimal image quality. Model performance in the validation sample was excellent (C statistic = 0.74 [95% CI, 0.73-0.75]; calibration slope = 1.11 [95% CI, 1.06-1.15]).

CONCLUSIONS

In this large, single-center, retrospective study, UEA use remained substantially below rates of suboptimal image quality, despite increases over time. Among outpatients, a simple prediction rule using three routinely collected variables available before TTE image acquisition predicted potential benefit from UEAs with high accuracy. If confirmed in other cohorts, this rule may be used to identify patients who may benefit from intravenous placement for UEA administration before TTE image acquisition, thus potentially improving work-flow efficiency.