Justin Godown

The utility of handheld echocardiography for early rheumatic heart disease diagnosis: A field study

AIMS The World Heart Federation (WHF) guidelines for rheumatic heart disease (RHD) are designed for a standard portable echocardiography (STAND) machine. A recent study in a tertiary care centre demonstrated that they also had good sensitivity and specificity when modified for use with handheld echocardiography (HAND). Our study aimed to evaluate the performance of HAND for early RHD diagnosis in the setting of a large-scale field screening. METHODS AND RESULTS STAND was performed in 4773 children in Gulu, Uganda, with 10% randomly assigned to also undergo HAND. Additionally, any child with mitral or aortic regurgitation also underwent HAND. Studies were performed by experienced echocardiographers and blindly reviewed by cardiologists using 2012 WHF criteria, which were modified slightly for HAND--due to the lack of spectral Doppler capability. Paired echocardiograms were performed in 1420 children (mean age 10.8 and 53% female), resulting in 1234 children who were normal, 133 who met criteria for borderline RHD, 47 who met criteria for definite RHD, and 6 who had other diagnoses. HAND had good sensitivity and specificity for RHD detection (78.9 and 87.2%, respectively), but was most sensitive for definite RHD (97.9%). Inter- and intra-reviewer agreement ranged between 66-83 and 71.4-94.1%, respectively. CONCLUSIONS HAND has good sensitivity and specificity for diagnosis of early RHD, performing best for definite RHD. Protocols for RHD detection utilizing HAND will need to include confirmation by STAND to avoid over-diagnosis. Strategies that evaluate simplified screening protocols and training of non-physicians hold promise for more wide spread deployment of HAND-based protocols.

Handheld echocardiography versus auscultation for detection of rheumatic heart disease

BACKGROUND: Rheumatic heart disease (RHD) remains a major public health concern in developing countries, and routine screening has the potential to improve outcomes. Standard portable echocardiography (STAND) is far more sensitive than auscultation for the detection of RHD but remains cost-prohibitive in resource-limited settings. Handheld echocardiography (HAND) is a lower-cost alternative. The purpose of this study was to assess the incremental value of HAND over auscultation to identify RHD. METHODS: RHD screening was completed for schoolchildren in Gulu, Uganda, by using STAND performed by experienced echocardiographers. Any child with mitral or aortic regurgitation or stenosis plus a randomly selected group of children with normal STAND findings underwent HAND and auscultation. STAND and HAND studies were interpreted by 6 experienced cardiologists using the 2012 World Heart Federation criteria. Sensitivity and specificity of HAND and auscultation for the detection of RHD and pathologic mitral or aortic regurgitation were calculated by using STAND as the gold standard. RESULTS: Of 4773 children who underwent screening with STAND, a subgroup of 1317 children underwent HAND and auscultation. Auscultation had uniformly poor sensitivity for the detection of RHD or valve disease. Sensitivity was significantly improved by using HAND compared with auscultation for the detection of definite RHD (97.8% vs 22.2%), borderline or definite RHD (78.4% vs 16.4%), and pathologic aortic insufficiency (81.8% vs 13.6%). CONCLUSIONS: Auscultation alone is a poor screening test for RHD. HAND significantly improves detection of RHD and may be a cost-effective screening strategy for RHD in resource-limited settings.

Simplified Rheumatic Heart Disease Screening Criteria for Handheld Echocardiography

BACKGROUND Using 2012 World Heart Federation criteria, standard portable echocardiography (STAND) reveals a high burden of rheumatic heart disease (RHD) in resource-poor settings, but widespread screening is limited by cost and physician availability. Handheld echocardiography (HAND) may decrease costs, but World Heart Federation criteria are complicated for rapid field screening, particularly for nonphysician screeners. The aim of this study was to determine the best simplified screening strategy for RHD detection using HAND. METHODS In this prospective study, STAND (GE Vivid q or i or Philips CX-50) was performed in five schools in Gulu, Uganda; a random subset plus all children with detectable mitral regurgitation or aortic insufficiency also underwent HAND (GE Vscan). Borderline or definite RHD cases were defined by 2012 World Heart Federation criteria on STAND images, by two experienced readers. HAND studies were reviewed by cardiologists blinded to STAND results. Single and combined HAND parameters were evaluated to determine the simplified screening strategy that maximized sensitivity and specificity for case detection. RESULTS In 1,439 children (mean age, 10.8 ± 2.6 years; 47% male) with HAND and STAND studies, morphologic criteria and the presence of any mitral regurgitation by HAND had poor specificity. The presence of aortic insufficiency was specific but not sensitive. Combined criteria of mitral regurgitation jet length ≥ 1.5 cm or any aortic insufficiency best balanced sensitivity (73.3%) and specificity (82.4%), with excellent sensitivity for definite RHD (97.9%). With a prevalence of 4% and subsequent STAND screening of positive HAND studies, this would reduce STAND studies by 80% from a STAND-based screening strategy. CONCLUSIONS In resource-limited settings, HAND with simplified criteria can detect RHD with good sensitivity and specificity and decrease the need for standard echocardiography. Further study is needed to validate screening by local practitioners and long-term outcomes.

Variation in the use of surveillance endomyocardial biopsy among pediatric heart transplant centers over time

EMB is widely utilized for graft surveillance after HTx; however, there is significant variation in the frequency of surveillance EMB use during the first year post‐HTx. The aim of this study was to assess changes in the utilization of surveillance EMB over time among member institutions of PHTS. A survey of PHTS centers assessing the frequency of surveillance EMB use during the first year post‐HTx was conducted in 2006. The same survey was repeated in 2014 to assess changes in practice over time. The number of EMB in infants ranged from 0 to 9 and in adolescents 0 to 16. The number of EMB decreased or remained unchanged in the majority of centers. Fewer EMB are performed in infants compared to adolescents and this practice did not change over time. There was a significant decrease in surveillance EMB use in adolescents (p = 0.012). International centers perform significantly fewer EMB in adolescents when compared to centers within the United States (p = 0.006). There continues to be significant variation in the utilization of surveillance EMB, with a shift toward less reliance on EMB for adolescents in the current era. Further research is necessary to determine the optimal frequency of invasive monitoring that reduces costs without compromising outcomes.

Differential effect of body mass index on pediatric heart transplant outcomes based on diagnosis

The impact of nutritional status on HTx waitlist mortality in children is unknown, and there are conflicting data regarding the role of nutrition in post‐HTx survival. This study examined the influence of nutrition on waitlist and post‐HTx outcomes in children. Children 2–18 yr listed for HTx from 1997 to 2011 were identified from the OPTN database and stratified by BMI percentile. Multivariable logistic regression evaluated the influence of BMI on waitlist mortality. Cox proportional hazard regression assessed the impact of BMI on post‐HTx mortality. When all 2712 patients were analyzed, BMI did not impact waitlist, one‐, or five‐yr mortality. However, when stratified by diagnosis, BMI > 95% (AOR 1.96; 95% CI 1.24, 3.09) and BMI < 1% (AOR 2.17; 95% CI 1.28, 3.68) were independent risk factors for waitlist mortality in patients with CM. BMI did not impact waitlist mortality in CHD and did not impact post‐HTx outcomes, regardless of diagnosis. BMI > 95% and BMI < 1% are independent risk factors for waitlist mortality in patients with CM, but not CHD. This suggests differing risk factors based on disease etiology, and an individualized approach to risk assessment based on diagnosis may be warranted.

Expanding the donor pool: regional variation in pediatric organ donation rates.

There are limited published data on pediatric organ donation rates. The aim of this study was to describe the trends in pediatric organ donation over time and to assess the regional variation in pediatric deceased organ donation. OPTN data were utilized to assess the trends in pediatric organ donation over time. The number of deceased pediatric organ donors was indexed using regional mortality data obtained from the National Center for Health Statistics and compared across UNOS regions and two different eras. The number of pediatric deceased organ donors has declined in the recent era, largely driven by fewer adolescent donors. For all age groups, there is significant regional variation in organ donation rates, with identifiable high‐ and low‐performing regions. Expansion of the donor pool may be possible by optimizing organ donation in regions demonstrating lower recruitment of pediatric donors. Using the region with the highest donation rate for each age group as the gold standard, we estimate a potential 24% increase in the number of donors if all regions performed comparably, equating to 215 new pediatric donors annually.

Abnormal nutrition affects waitlist mortality in infants awaiting heart transplant

BACKGROUND Although nutritional status affects survival after heart transplant (HTx) in adults and older children, its effect on outcomes in young children is unknown. This study aimed to assess the effect of pre-HTx nutrition on outcomes in this population. METHODS Children aged 0 to 2 years old listed for HTx from 1997 to 2011 were identified from the Organ Procurement and Transplantation Network database. Nutritional status was classified according to percentage of ideal body weight at listing and at HTx. Logistic regression analysis evaluated the risk of waitlist mortality. Cox proportional hazard models assessed the effect of nutrition on post-HTx survival. RESULTS Of 1,653 children evaluated, 899 (54%) had normal nutrition at listing, 445 (27%) were mildly wasted, 203 (12%) were moderate or severely wasted, and 106 (6%) had an elevated weight-to-height (W:H) ratio. Moderate or severe wasting (adjusted odds ratio, 1.9; 95% confidence interval, 1.3-2.7) and elevated W:H (adjusted odds ratio, 1.7; 95% confidence interval, 1.1-2.6) were independent risk factors for waitlist mortality. HTx was performed in 1,167 patients, and 1,016 (87%) survived to 1-year post-HTx. Nutritional status at listing or at HTx was not associated with increased post-HTx mortality. Nutritional status did not affect the need for early reoperation, dialysis, or the incidences of infection, stroke, or rejection before hospital discharge. CONCLUSIONS Moderate or severe wasting and an elevated W:H are independent risk factors for waitlist mortality in patients aged < 2 years but do not affect post-HTx mortality. Optimization of pre-HTx nutritional status constitutes a strategy to reduce waitlist mortality in this age range.

Regional variation in the use of 1A status exceptions for pediatric heart transplant candidates: is this equitable?

The use of status exceptions (SE) was recently publicized as a strategy to reduce waitlist times for children awaiting heart transplant (HTx). The aim of this study was to assess SE use across UNOS regions and compare survival in patients listed using a SE to those listed by standard criteria. The OPTN database was queried for all pediatric patients listed for HTx (2000–2014). SE use was compared across UNOS regions. Survival curves were generated and compared using the log‐rank test. 1A SE use is uncommon, being utilized in 108 of 4587 pediatric 1A listings (2.4%). There is significant variability in SE use across UNOS regions (0.7%–16.4% of 1A listings, P < .001). Waitlist survival is significantly higher in candidates listed using a 1A SE compared to those listed by standard criteria (P = .001) and is similar to 1B listings. Regional variation in 1A SE use has the potential to introduce bias into a system designed to be equitable. Waitlist survival in patients listed using a SE is similar to those listed status 1B, suggesting these patients may not require 1A status. Careful review of pediatric heart allocation policies is needed to optimize patient outcomes and ensure a fair and unbiased allocation system.

A unique linkage of administrative and clinical registry databases to expand analytic possibilities in pediatric heart transplantation research

Background Large clinical, research, and administrative databases are increasingly utilized to facilitate pediatric heart transplant (HTx) research. Linking databases has proven to be a robust strategy across multiple disciplines to expand the possible analyses that can be performed while leveraging the strengths of each dataset. We describe a unique linkage of the Scientific Registry of Transplant Recipients (SRTR) database and the Pediatric Health Information System (PHIS) administrative database to provide a platform to assess resource utilization in pediatric HTx. Methods All pediatric patients (1999–2016) who underwent HTx at a hospital enrolled in the PHIS database were identified. A linkage was performed between the SRTR and PHIS databases in a stepwise approach using indirect identifiers. To determine the feasibility of using these linked data to assess resource utilization, total and post‐HTx hospital costs were assessed. Results A total of 3188 unique transplants were identified as being present in both databases and amenable to linkage. Linkage of SRTR and PHIS data was successful in 3057 (95.9%) patients, of whom 2896 (90.8%) had complete cost data. Median total and post‐HTx hospital costs were

Risk factors for the development of donor-specific antibodies after pediatric heart transplantation.

518,906 (IQR