Practice Variations in Pediatric Echocardiography Laboratories

Contemporary transesophageal echocardiography practice patterns among paediatric cardiology centres in the United States and Canada

OBJECTIVE

To characterise transesophageal echocardiography practice patterns among paediatric cardiac surgical centres in the United States and Canada.

METHODS

A 42-question survey was sent to 80 echocardiography laboratory directors at paediatric cardiology centres with surgical programmes in the United States and Canada. Question domains included transesophageal echocardiography centre characteristics, performance and reporting, equipment use, trainee participation, and quality assurance.

RESULTS

Fifty of the 80 centres (62.5%) responded to the survey. Most settings were academic (86.0%) with 42.0% of centres performing > 350 surgical cases/year. The median number of transesophageal echocardiograms performed/cardiologist/year was 50 (26, 73). Pre-operative transesophageal echocardiography was performed in most surgical cases by 91.7% of centres. Transesophageal echocardiography was always performed by most centres following Norwood, Glenn, and Fontan procedures and by < 10% of centres following coarctation repair. Many centres with a written guideline allowed transesophageal echocardiography transducer use at weights below manufacturer recommendations (50.0 and 61.1% for neonatal and paediatric transducers, respectively). Most centres (36/37, 97.3%) with categorical fellowships had rotations which included transesophageal echocardiography participation. Large surgical centres (>350 cases/year) had higher median number of transesophageal echocardiograms/cardiologist/year (75.5 [53, 86] versus 35 [20, 52], p < 0.001) and more frequently used anaesthesia for diagnostic transesophageal echocardiography ≥ 67% of time (100.0 versus 62.1%, p = 0.001).

CONCLUSIONS

There is significant variability in transesophageal echocardiography practice patterns and training requirements among paediatric cardiology centres in the United States and Canada. Findings may help inform programmatic decisions regarding transesophageal echocardiography expectations, performance and reporting, equipment use, trainee involvement, and quality assurance.

Guidelines for Performing a Comprehensive Pediatric Transthoracic Echocardiogram: Recommendations From the American Society of Echocardiography

Echocardiography is a fundamental component of pediatric cardiology, and appropriate indications have been established for its use in the setting of suspected, congenital, or acquired heart disease in children. Since the publication of guidelines for pediatric transthoracic echocardiography in 2006 and 2010, advances in knowledge and technology have expanded the scope of practice beyond the use of traditional modalities such as two-dimensional, M-mode, and Doppler echocardiography to evaluate the cardiac segmental structures and their function. Adjunct modalities such as contrast, three-dimensional, and speckle-tracking echocardiography are now used routinely at many pediatric centers. Guidelines and recommendations for the use of traditional and newer adjunct modalities in children are described in detail in this document. In addition, suggested protocols related to standard operations, infection control, sedation, and quality assurance and improvement are included to provide an organizational structure for centers performing pediatric transthoracic echocardiograms.

Utility of apical four-chamber longitudinal strain in the assessment of childhood cancer survivors: A multicenter study

BACKGROUND

A previous multicenter study showed that longitudinal changes in standard cardiac functional parameters were associated with the development of cardiomyopathy in childhood cancer survivors (CCS). Evaluation of the relationship between global longitudinal strain (GLS) changes and cardiomyopathy risk was limited, largely due to lack of quality apical 2- and 3-chamber views in addition to 4-chamber view. We sought to determine whether apical 4-chamber longitudinal strain (A4LS) alone can serve as a suitable surrogate for GLS in this population.

METHODS

A4LS and GLS were measured in echocardiograms with acceptable apical 2-, 3-, and 4-chamber views. Correlation was evaluated using Pearson and Spearman coefficients, and agreement was evaluated with Bland-Altman plots. The ability of A4LS to identify normal and abnormal values compared to GLS as the reference was evaluated.

RESULTS

Among a total of 632 reviewed echocardiograms, we identified 130 echocardiograms from 56 patients with adequate views (38% female; mean age at cancer diagnosis 8.3 years; mean follow-up 9.4 years). Correlation coefficients between A4LS and GLS were .89 (Pearson) and .85 (Spearman), with Bland-Altman plot of GLS-A4LS showing a mean difference of -.71 ± 1.8. Compared with GLS as the gold standard, A4LS had a sensitivity of 86% (95% CI 79%-93%) and specificity of 82% (69%-95%) when using normal range cutoffs and 90% (82%-97%) and 70% (58%-81%) when using ±2 standard deviations.

CONCLUSION

A4LS performs well when compared with GLS in this population. Given the more recent adoption of apical 2- and 3-chamber views in most pediatric echocardiography laboratories, A4LS is a reasonable stand-alone measurement in retrospective analyses of older study cohorts and echocardiogram biorepositories.

Survey of centers performing cardiovascular magnetic resonance in pediatric and congenital heart disease: a report of the Society for Cardiovascular Magnetic Resonance

BACKGROUND

There are few data on practice patterns and trends for cardiovascular magnetic resonance (CMR) in pediatric and congenital heart disease. The Society for Cardiovascular Magnetic Resonance (SCMR) sought to address this deficiency by performing an international survey of CMR centers.

METHODS

Surveys consisting of 31 (2014) and 33 (2018) items were designed to collect data on the use of CMR for the evaluation of pediatric and congenital heart disease patients. They were sent to all SCMR members in 2014 and 2018. One response per center was collected.

RESULTS

There were 93 centers that responded in 2014 and 83 in 2018. The results that follow show data from 2014 and 2018 separated by a dash. The median annual number of pediatric/congenital CMR cases per center was 183-209. The median number of scanners for CMR was 2-2 (range, 1-8) with 58-63% using only 1.5T scanners and 4-4% using only 3T scanners. The mean number of attending/staff reading CMRs was 3.7-2.6; among them, 52-61% were pediatric or adult cardiologists and 47-38% were pediatric or adult radiologists. The median annual case volume per attending was 54-86. The median number of technologists per center doing CMRs was 4-5. The median scanner time allocated for a non-sedated examination was 75-75 min (range, 45-120). Among the 21 centers responding to both surveys, the mean annual case volume increased from 320 in 2014 to 445 in 2018; 17 (81%) of the centers had an increase in annual case volume. For this subgroup, the median attending/staff per center was 4 in both 2014 and 2018. The median scanner time allotted per study was unchanged at 90 min. The mean time for an attending/staff physician to perform a typical CMR examination including reporting was 143-141 min.

CONCLUSION

These survey data provide a novel comprehensive view of CMR practice in pediatric and congenital heart disease. This information is useful for internal benchmarking, resource allocation, addressing practice variation, quality improvement initiatives, and identifying unmet needs.

Challenges associated with retrospective analysis of left ventricular function using clinical echocardiograms from a multicenter research study

BACKGROUND

Retrospective multicenter research using echocardiograms obtained for routine clinical care can be hampered by issues of individual center quality. We sought to evaluate imaging and patient characteristics associated with poorer quality of archived echocardiograms from a cohort of childhood cancer survivors.

METHODS

A single blinded reviewer at a central core laboratory graded quality of clinical echocardiograms from five centers focusing on images to derive 2D and M-mode fractional shortening (FS), biplane Simpson's ejection fraction (EF), myocardial performance index (MPI), tissue Doppler imaging (TDI)-derived velocities, and global longitudinal strain (GLS).

RESULTS

Of 535 studies analyzed in 102 subjects from 2004 to 2017, all measures of cardiac function could be assessed in only 7%. While FS by 2D or M-mode, MPI, and septal E/E' could be measured in >80% studies, mitral E/E' was less consistent (69%), but better than EF (52%) and GLS (10%). 66% of studies had ≥1 issue, with technical issues (eg, lung artifact, poor endocardial definition) being the most common (33%). Lack of 2- and 3-chamber views was associated with the performing center. Patient age <5 years had a higher chance of apex cutoff in 4-chamber views compared with 16-35 years old. Overall, for any quality issue, earlier era of echo and center were the only significant risk factors.

CONCLUSION

Assessment of cardiac function using pooled multicenter archived echocardiograms was significantly limited. Efforts to standardize clinical echocardiographic protocols to include apical 2- and 3-chamber views and TDI will improve the ability to quantitate LV function.

Using Quality Improvement Methodology to Standardize Doppler Acquisition in a Pediatric Cardiology Echocardiography Laboratory

In echocardiography, the Doppler principle allows the measurement of tissue velocities. Using the Bernoulli equation, velocities are translated to estimated pressure differences, which dictate the timing of cardiac interventions. Our echocardiography laboratory demonstrated variability in the Doppler interrogation of heart valves, leading to difficulties in comparison over time and study accuracy. To align with previously published quality metrics in echocardiography, our laboratory used quality improvement methodology to achieve measurable improvement in Doppler acquisition.

Methods

We developed a standardized protocol for Doppler acquisition and translated it to a 20-point scoring system. We established a baseline over 4 months via random assessment of 2 first-time, normal studies per day. Interventions included standardizing the process for acquisition, education, visual tracking, and individual feedback.

Results

The percentage of studies with a score of 16 or higher preintervention was 17%. The median score was 13.4. In total, we analyzed 407 studies, 173 pre- and 234 postintervention. Over a 4-month intervention period, the median score improved to 18.1, with 85% of studies achieving a score of 16 or higher. Special cause variation occurred after protocol distribution, education, and feedback.

Conclusions

Our initiative demonstrated significant improvement in the Doppler interrogation of cardiac structures using a measurable scoring system and a concrete goal of incorporating 20 areas of Doppler assessment in normal studies. Our next step is to spread this assessment to abnormal studies, thus developing consistency in evaluating all studies throughout the laboratory.

A standardized imaging protocol improves quality and reduces practice variability in echocardiographic assessment of ventricular function by first-year pediatric cardiology fellows

BACKGROUND

Echocardiography education for pediatric cardiology fellows has been a recent focus leading to the implementation of "boot camps." Less is described about continuing education through fellowship and improving image quality. We noticed practice variation in echocardiograms assessing ventricular function performed on nights and weekends. Thus, we implemented a standardized protocol and assessed its impact on imaging and reporting completeness.

METHODS

We created an imaging protocol for the assessment of ventricular function in the acute setting. The protocol included demographic information, a list of images to be obtained, and the methods to quantify ventricular function. The protocol was explained to first-year fellows and distributed on an electronic quick reference card. Echocardiograms independently performed by first-year fellows during their first 4 months of on-call time were assessed pre- and postintervention using a standard rubric.

RESULTS

Compliance with demographic reporting was high pre- and postintervention, but significantly improved after the standardized protocol (P < 0.001). Use of the protocol increased the median number of unique images obtained per echocardiogram from 13 to 17 (out of 23 required views, P < 0.001). Particularly improved was the performance of quantitative evaluations of function, including Simpson's method for left ventricular ejection fraction (four chamber: 40% vs 67%, P < 0.001; two chamber: 33% vs 67%, P < 0.001) and tricuspid annular plane systolic excursion (45% vs 80%, P < 0.001).

CONCLUSIONS

The introduction of a standardized imaging protocol and its distribution to first-year fellows resulted in improvements in echocardiographic reporting completeness and increased the quality of information obtained by providing more quantitative assessments of ventricular function.