Does the External Pericardial Lateral Tunnel Fontan Pathway Enlarge to Accommodate Somatic Growth? A Preliminary Analysis.

Objectives: An ideal Fontan pathway should be capable of adapting to changes in circulatory demands. The external pericardial lateral tunnel Fontan (EPLTF) is constructed of viable, autologous tissue and may be capable of changing in size. We investigated the ability of the EPLTF to enlarge with increasing physiologic demands of somatic growth. Methods: Retrospective review of echocardiographic images for patients with a minimum of five years follow-up after EPLTF. Serial echocardiographic measurements of the EPLTF pathway were obtained at three distinct locations: the inferior vena cava junction with the EPLTF, midsection of the EPLTF, and cross-sectional area of the EPLTF visualized in a four-chamber view. Body surface area (BSA) was calculated at the time of each echocardiographic measurement. Changes in echocardiographic measurements over time were analyzed and compared with changes in BSA. Results: A total of 332 echocardiographic studies from 38 patients were reviewed. Significant enlargement of the EPLTF pathway is observed at the inferior vena caval junction (P < .001), midsection (P < .01), and cross-sectional area (P < .001). Repeated measures correlation between pathway measurements and BSA is highly significant (P < .001). Conclusions: The EPLTF pathway enlarges over time in correlation with increasing BSA. Further research is needed to define ideal pathway size, differentiate normal physiologic growth from pathologic enlargement, and correlate changes with clinical outcomes.

Novel handheld ultrasound technology to enhance non-expert screening for rheumatic heart disease in the Republic of Palau: A descriptive study.

AIM: Non-expert training in rheumatic heart disease (RHD) detection is a valuable strategy in resource-limited settings. Here we present an innovative handheld ultrasound application featuring views of correct probe position, imaging protocol and echocardiographic loops of RHD pathology versus normal, accessible during real-time scanning. METHODS: This prospective study was implemented into a pre-existing school health screening programme at an elementary school in Koror, Palau. Six learners with no prior ultrasound experience were taught a simplified screening protocol in which a mitral regurgitation jet ≥1.5 cm and/or presence of aortic insufficiency were considered a positive screen. All consented children underwent echocardiographic screening by experts with standard portable echocardiography. All positive cases and 25% of negative cases were referred for handheld scans by learners. RESULTS: A total of 26 (4.1%) children were diagnosed with borderline or definite RHD. Mean sensitivity and specificity compared to expert RHD diagnosis over all learners was 71% (standard deviation (SD) 11.3) and 92% (SD 4.9), respectively. For the three highest scanning learners, mean sensitivity was 88% (SD 4.9) and mean specificity was 90% (SD 5.7). For all definite RHD cases, sensitivity was 100% for all but one learner, who achieved sensitivity of 60%. The novel application was used in 229 of 624 (36%) of all handheld scans and 50 of 112 (45%) of expert-diagnosed positive scans, with protocol and reference features most frequently used. Utilisation of the novel application overall decreased per day of scanning per learner. CONCLUSION: Adjunctive handheld ultrasound technology may help ease non-experts into RHD screening.

The personal and clinical impact of screen-detected maternal rheumatic heart disease in Uganda: a prospective follow up study.

BACKGROUND: Pre-existing maternal cardiac disease is a significant contributor to adverse maternal, fetal, and neonatal outcomes. In 2015-2017, our team conducted the first community-based study of maternal rheumatic heart disease (RHD) in sub-Saharan Africa and identified RHD in 88% of those with pre-existing heart disease. Here we conducted a follow up investigation of women previously identified with RHD, describing clinical and echocardiographic outcomes, identifying barriers to medical adherence and evaluating the personal impact of RHD. METHODS: A 2 week prospective follow up was completed at sites in Central and Eastern Uganda. Participants underwent a three-step mixed methods study comprising of 1) direct structured interview targeting clinical history and medication adherence, 2) echocardiogram to evaluate left-sided heart valves, and 3) semi-structured guideline interview to elicit personal impacts of RHD. RESULTS: The team evaluated 40 (80%) of the original 51 mothers with RHD at a median post-partum time of 2.5 years after delivery (IQR 0.5). Echocardiographic data showed improvement in nine women with the remaining 31 women showing stable echocardiographic findings. Adherence to Benzathine penicillin G (BPG) prophylaxis was poor, with 70% of patients either poorly adherent or non-adherent. Three major themes emerged from interviews: 1) social determinants of health (World Health Organization, Social determinants of health, 2019) negatively affecting healthcare, 2) RHD diagnosis negatively affecting female societal wellbeing, 3) central role of spouse in medical decision making. CONCLUSIONS: Screening echocardiography can identify women with pre-existing rheumatic heart disease during pregnancy, but long-term follow-up in Uganda reveals adherence to medical care following diagnosis, including BPG, is poor. Additionally, mothers diagnosed with RHD may experience unintended consequences such as social stigmatization. As identification of occult RHD is critical to prevent adverse pregnancy outcomes, further research is needed to determine how to best support women who face a new diagnosis of RHD, and to determine the role of screening echocardiography in high-risk settings.

Troponin I Levels Correlate with Cardiac MR LGE and Native T1 Values in Duchenne Muscular Dystrophy Cardiomyopathy and Identify Early Disease Progression.

Cardiomyopathy is the leading cause of death in Duchenne muscular dystrophy (DMD). Elevated troponin levels are observed in DMD and may vary with disease progression. We studied troponin levels in DMD related to cardiac fibrosis and native T1 measures. This is a prospective, cross-sectional, observational study of 30 DMD subjects measuring native T1 levels and late gadolinium enhancement (LGE) on cardiac MR imaging (CMR) correlated with temporally associated serum troponin I levels. Non-parametric analyses including Spearman correlations and Kruskal-Wallis test were performed between groups. p values resulting from the pair-wise comparisons were adjusted for multiple comparisons using the Sidak method where appropriate. There were 15 DMD subjects with no LGE (age 12 ± 3 yo; EF% 60 ± 5) and troponin I level of 0.05 ± 0.08 ng/ml, of which three had an abnormal troponin level (over 0.04 ng/ml); 7 DMD subjects with mild LGE (age 17 ± 5 yo, EF% 52 ± 8) and troponin I level of 0.28 ± 0.36 ng/ml, of which five had an abnormal troponin level; and 8 DMD subjects with moderate-to-severe LGE (age 16 ± 6 yo; EF% 54 ± 8) and troponin I level of 0.11 ± 0.14 ng/ml, of which four had an abnormal troponin level. Troponin I levels in DMD subjects with mild LGE was significantly increased compared to subjects with no LGE (p = 0.02). There was a statistically significant positive correlation between troponin I levels and MOLLI septal native T1 values (r2 = 0.173, p = 0.02). Overall, MOLLI lateral native T1 levels were increased with moderate-severe LGE compared to mild and none (p < 0.01). Serum biomarker troponin I levels were increased in DMD subjects with mild LGE and correlated with MOLLI septal native T1 values. Troponin I levels may be a useful minimally invasive outcome marker to monitor myocardial disease progression in DMD cardiomyopathy.