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Characteristics of Cardiac Abnormalities in Pediatric Patients With Acute COVID-19

Pasternack, Daniel; Singh, Rakesh K; Minocha, Prashant K; Farkas, Jon S; Ramaswamy, Prema; Better, Donna; Verma, Sourabh; Phoon, Colin K
Introduction Coronavirus disease 2019 (COVID-19) is known to cause cardiac abnormalities in adults. Cardiac abnormalities are well-described in multisystem inflammatory syndrome in children, but effects in children with acute COVID-19 are less understood. In this multicenter study, we assessed the cardiac effects of acute COVID-19 among hospitalized children (<21 years) admitted to three large healthcare systems in New York City. Methods We performed a retrospective observational study. We examined electrocardiograms, echocardiograms, troponin, or B-type natriuretic peptides. Results Of 317 admitted patients, 131 (41%) underwent cardiac testing with 56 (43%) demonstrating cardiac abnormalities. Electrocardiogram abnormalities were the most common (46/117 patients (39%)), including repolarization abnormalities and QT prolongation. Elevated troponin occurred in 14/77 (18%) patients and B-type natriuretic peptide in 8/39 (21%) patients. Ventricular dysfunction was identified in 5/27 (19%) patients with an echocardiogram, all of whom had elevated troponin. Ventricular dysfunction resolved by first outpatient follow-up. Conclusion Electrocardiogram and troponin can assist clinicians in identifying children at risk for cardiac injury in acute COVID-19.
PMID: 37065296
ISSN: 2168-8184
CID: 5459202

Prospective Evaluation of High Titer Autoantibodies and Fetal Home Monitoring in the Detection of Atrioventricular Block Among Anti-SSA/Ro Pregnancies

Buyon, Jill P.; Masson, Mala; Izmirly, Caroline G.; Phoon, Colin; Acherman, Ruben; Sinkovskaya, Elena; Abuhamad, Alfred; Makhoul, Majd; Satou, Gary; Hogan, Whitnee; Pinto, Nelangi; Moon-Grady, Anita; Howley, Lisa; Donofrio, Mary; Krishnan, Anita; Ahmadzia, Homa; Levasseur, Stephanie; Paul, Erin; Owens, Sonal; Cumbermack, Kristopher; Matta, Jyothi; Joffe, Gary; Lindblade, Christopher; Haxel, Caitlin; Kohari, Katherine; Copel, Joshua; Strainic, James; Doan, Tam; Bermudez-Wagner, Karla; Holloman, Conisha; Sheth, Shreya S.; Killen, Stacy; Tacy, Theresa; Kaplinski, Michelle; Hornberger, Lisa; Carlucci, Philip M.; Izmirly, Peter; Fraser, Nicola; Clancy, Robert M.; Cuneo, Bettina F.
Objective: This prospective study of pregnant patients, Surveillance To Prevent AV Block Likely to Occur Quickly (STOP BLOQ), addresses the impact of anti-SSA/Ro titers and utility of ambulatory monitoring in the detection of fetal second-degree atrioventricular block (AVB). Methods: Women with anti-SSA/Ro autoantibodies by commercial testing were stratified into high and low anti"“52-kD and/or 60-kD SSA/Ro titers applying at-risk thresholds defined by previous evaluation of AVB pregnancies. The high-titer group performed fetal heart rate and rhythm monitoring (FHRM) thrice daily and weekly/biweekly echocardiography from 17"“26 weeks. Abnormal FHRM prompted urgent echocardiography to identify AVB. Results: Anti"“52-kD and/or 60-kD SSA/Ro met thresholds for monitoring in 261 of 413 participants (63%); for those, AVB frequency was 3.8%. No cases occurred with low titers. The incidence of AVB increased with higher levels, reaching 7.7% for those in the top quartile for anti"“60-kD SSA/Ro, which increased to 27.3% in those with a previous child who had AVB. Based on levels from 15 participants with paired samples from both an AVB and a non-AVB pregnancy, healthy pregnancies were not explained by decreased titers. FHRM was considered abnormal in 45 of 30,920 recordings, 10 confirmed AVB by urgent echocardiogram, 7 being second-degree AVB, all <12 hours from normal FHRM and within another 0.75 to 4 hours to echocardiogram. The one participant with second/third-degree and two participants with third-degree AVB were diagnosed by urgent echocardiogram >17 to 72 hours from an FHRM. Surveillance echocardiograms detected no AVB when the preceding interval FHRM recordings were normal. Conclusion: High-titer antibodies are associated with an increased incidence of AVB. Anti-SSA/Ro titers remain stable over time and do not explain the discordant recurrence rates, suggesting that other factors are required. Fetal heart rate and rhythm (FHRM) with results confirmed by a pediatric cardiologist reliably detects conduction abnormalities, which may reduce the need for serial echocardiograms. (Figure presented.).
ISSN: 2326-5191
CID: 5615912

Genetic Basis of Left Ventricular Noncompaction

Rojanasopondist, Pakdee; Nesheiwat, Leigh; Piombo, Sebastian; Porter, George A; Ren, Mindong; Phoon, Colin K L
BACKGROUND:Left ventricular noncompaction (LVNC) is the third most common pediatric cardiomyopathy characterized by a thinned myocardium and prominent trabeculations. Next-generation genetic testing has led to a rapid increase in the number of genes reported to be associated with LVNC, but we still have little understanding of its pathogenesis. We sought to grade the strength of the gene-disease relationship for all genes reported to be associated with LVNC and identify molecular pathways that could be implicated. METHODS:Following a systematic PubMed review, all genes identified with LVNC were graded using a validated, semi-quantitative system based on all published genetic and experimental evidence created by the Clinical Genome Resource (ClinGen). Genetic pathway analysis identified molecular processes and pathways associated with LVNC. RESULTS:We identified 189 genes associated with LVNC: 11 (6%) were classified as definitive, 21 (11%) were classified as moderate, and 140 (74%) were classified as limited, but 17 (9%) were classified as no evidence. Of the 32 genes classified as definitive or moderate, the most common gene functions were sarcomere function (n=11; 34%), transcriptional/translational regulator (n=6; 19%), mitochondrial function (n=3; 9%), and cytoskeletal protein (n=3; 9%). Furthermore, 18 (56%) genes were implicated in noncardiac syndromic presentations. Lastly, 3 genetic pathways (cardiomyocyte differentiation via BMP receptors, factors promoting cardiogenesis in vertebrates, and Notch signaling) were found to be unique to LVNC and not overlap with pathways identified in dilated cardiomyopathy and hypertrophic cardiomyopathy. CONCLUSIONS:LVNC is a genetically heterogeneous cardiomyopathy. Distinct from dilated or hypertrophic cardiomyopathies, LVNC appears to arise from abnormal developmental processes.
PMID: 35549379
ISSN: 2574-8300
CID: 5214612

The remarkable Harriet Lane

Phoon, Colin KL
ISSN: 2155-3017
CID: 5295612

LPGAT1 controls the stearate/palmitate ratio of phosphatidylethanolamine and phosphatidylcholine in sn-1 specific remodeling

Xu, Yang; Miller, Paighton C; Phoon, Colin K L; Ren, Mindong; Nargis, Titli; Rajan, Sujith; Hussain, M Mahmood; Schlame, Michael
Most mammalian phospholipids contain a saturated fatty acid at the sn-1 carbon atom and an unsaturated fatty acid at the sn-2 carbon atom of the glycerol backbone group. While the sn-2 linked chains undergo extensive remodeling by deacylation and reacylation (Lands cycle), it is not known how the composition of saturated fatty acids is controlled at the sn-1 position. Here, we demonstrate that lysophosphatidylglycerol acyltransferase 1 (LPGAT1) is an sn-1 specific acyltransferase that controls the stearate/palmitate ratio of phosphatidylethanolamine (PE) and phosphatidylcholine. Bacterially expressed murine LPGAT1 transferred saturated acyl-CoAs specifically into the sn-1 position of lysophosphatidylethanolamine (LPE) rather than lysophosphatidylglycerol and preferred stearoyl-CoA over palmitoyl-CoA as the substrate. In addition, genetic ablation of LPGAT1 in mice abolished 1-LPE:stearoyl-CoA acyltransferase activity and caused a shift from stearate to palmitate species in PE, dimethyl-PE, and phosphatidylcholine. Lysophosphatidylglycerol acyltransferase 1 KO mice were leaner and had a shorter life span than their littermate controls. Finally, we show that total lipid synthesis was reduced in isolated hepatocytes of LPGAT1 knockout mice. Thus, we conclude that LPGAT1 is an sn-1 specific LPE acyltransferase that controls the stearate/palmitate homeostasis of PE and the metabolites of the PE methylation pathway and that LPGAT1 plays a central role in the regulation of lipid biosynthesis with implications for body fat content and longevity.
PMID: 35131264
ISSN: 1083-351x
CID: 5175992

A simple mechanistic explanation for Barth syndrome and cardiolipin remodeling

Xu, Yang; Phoon, Colin K L; Ren, Mindong; Schlame, Michael
Barth syndrome is a multisystem disorder caused by an abnormal metabolism of the mitochondrial lipid cardiolipin. In this review, we discuss physical properties, biosynthesis, membrane assembly, and function of cardiolipin. We hypothesize that cardiolipin reduces packing stress in the inner mitochondrial membrane, which arises as a result of protein crowding. According to this hypothesis, patients with Barth syndrome are unable to meet peak energy demands because they fail to concentrate the proteins of oxidative phosphorylation to a high surface density in the inner mitochondrial membrane.
PMID: 34611930
ISSN: 1573-2665
CID: 5067722

Truncus Arteriosus

Chapter by: Bhansali, Suneet; Phoon, Colin
in: StatPearls by
Treasure Island FL : StatPearls, 2022
pp. -
CID: 5295662

Condensed Mitochondria Assemble Into the Acrosomal Matrix During Spermiogenesis

Ren, Mindong; Xu, Yang; Phoon, Colin K L; Erdjument-Bromage, Hediye; Neubert, Thomas A; Rajan, Sujith; Hussain, M Mahmood; Schlame, Michael
Mammalian spermatogenesis is associated with the transient appearance of condensed mitochondria, a singularity of germ cells with unknown function. Using proteomic analysis, respirometry, and electron microscopy with tomography, we studied the development of condensed mitochondria. Condensed mitochondria arose from orthodox mitochondria during meiosis by progressive contraction of the matrix space, which was accompanied by an initial expansion and a subsequent reduction of the surface area of the inner membrane. Compared to orthodox mitochondria, condensed mitochondria respired more actively, had a higher concentration of respiratory enzymes and supercomplexes, and contained more proteins involved in protein import and expression. After the completion of meiosis, the abundance of condensed mitochondria declined, which coincided with the onset of the biogenesis of acrosomes. Immuno-electron microscopy and the analysis of sub-cellular fractions suggested that condensed mitochondria or their fragments were translocated into the lumen of the acrosome. Thus, it seems condensed mitochondria are formed from orthodox mitochondria by extensive transformations in order to support the formation of the acrosomal matrix.
PMID: 35531097
ISSN: 2296-634x
CID: 5214072


Buyon, J; Deonaraine, K; Carlucci, P; Masson, M; Fraser, N; Phoon, C; Roman, A; Izmirly, P; Saxena, A; Belmont, M; Penfield, C; Mi, Lee Y; Nusbaum, J; Solitar, B; Malik, F; Rackoff, P; Haberman, R; Acherman, R; Sinkovskaya, E; Albuhamad, A; Makhoul, M; Satou, G; Pinto, N; Moon-Grady, A; Howley, L; Levasseur, S; Matta, J; Lindblade, C; Rubenstein, A; Haxel, C; Kohari, K; Copel, J; Strainic, J; Doan, T; Bermudez-Wagner, K; Sheth, S S; Killen, S; Tacy, T; Kaplinski, M; Drewes, B; Clancy, R; Cuneo, B
Introduction Fetal cardiac disease is strongly associated with maternal anti-SSA/Ro antibodies, but gaps in our knowledge include the influence of antibody specificity and titer, maternal diagnosis, overall non-cardiac adverse pregnancy outcomes (APOs), optimal surveillance protocols, and efficacy of rapid treatment. Methods The multi-center Surveillance and Treatment To Prevent Fetal AV Block Likely to Occur Quickly (STOP BLOQ) study recruited pregnant women with commercially positive anti-Ro antibodies and stratified them into high and low titers of anti-Ro60 and Ro52 based on a research ELISA, using a cutoff defined by that obtained for 50 mothers with previous AVB offspring. Mothers with anti-Ro60 and/or 52 antibodies at or above 1,000 I.U. were trained to perform FHRM. From 17-25 weeks of gestation, FHRM was completed 3x/day in addition to weekly or biweekly fetal echocardiograms (echo). Mothers texted all audio sounds to the coordinating center. Texts deemed abnormal by mothers were immediately sent to an on call pediatric cardiologist who either reassured if FHRM was normal or referred for emergency fetal echo in < 6 hours if abnormal. Results 250 anti-Ro pregnant women (22% Hispanic, 50% white, 12% Black, 12% Asian, 4% other) have been consented, including 28 whose previous child had AVB. Of mothers tested to date, 153 were provided home monitors given high titer anti-Ro60 and/or 52 antibodies (26 high titer anti-Ro60 alone, 21 high titer anti-Ro52 alone,105 high titer antibodies to both antigens). The 83 patients with low titers were surveilled with echos per local standard of care. Regarding maternal diagnosis, of 161 assessed to date, 39% were asym/UAS, 11% RA, 31% SS, 19% SLE. Antibody titers did not significantly differ by ethnicity, race or diagnosis (table 1). Non-AVB APOs occurred in 18% and were not predicted by Ro60 or 52 titers but rather SLE diagnosis (table 2). In total, 24,759 FHRM audiotexts were received from 131 patients (90 of whom have delivered) during the monitoring period. Of these, 22 were evaluated by the on-call pediatric cardiologist, who prompted an emergency echo (all completed in < 6 hrs). In 11 cases, the emergency echo was normal. In 9, there were premature atrial contractions, confirming the mother's perception. In 2 with 2degree block on urgent echo (both treated per protocol with IVIG and dexamethasone), 1 reverted to normal sinus rhythm and the other progressed to 3degree block. In 2 others, the mother did not perceive abnormal FHRM for > 24 hrs, echo identified 3degree block, and retrospective cardiology review of FHRM audio captures identified an abnormality prior to obtaining the echo. All 4 AVB developed in fetuses of mothers with high titer antibodies to both Ro60 and 52 (mean 32,451 and 34,991 respectively). Of the 18 mothers with a previous AVB child who followed the 400mg hydroxychloroquine PATCH protocol, 1 developed AVB in accord with the results of Step 1 in that study. Conclusion These data support that APOs in this clinically diverse group of mothers are not influenced by anti-Ro titer or specificity, but rather SLE diagnosis. All conduction defects were initially identified by FHRM and in mothers with high titer anti-Ro60 and 52. Hydroxychloroquine continues to show efficacy in reducing the AVB recurrence rate with rapid intervention of emergent block being promising
ISSN: 2053-8790
CID: 5513372

Strain in children with MIS-C and acute COVID-19

Minocha, Prashant K; Srinivasan, Ranjini; Babb, James; Singh, Rakesh K; Phoon, Colin K L; Better, Donna; Bhatla, Puneet
CONTEXT/UNASSIGNED:Cardiac injury has been described in both acute COVID-19 and the multisystem inflammatory syndrome in children (MIS-C). Echocardiographic strain has been shown to be a sensitive measure of systolic function. AIMS/UNASSIGNED:We sought to describe strain findings in both the groups on initial presentation and follow-up. SETTINGS AND DESIGN/UNASSIGNED:A retrospective study analyzing echocardiograms of all patients presenting with acute COVID-19 infection and MIS-C at our institution between March 2020 and December 2020 was performed. SUBJECTS AND METHODS/UNASSIGNED:TOMTEC software was used for strain analysis in both the study groups (COVID-19 and MIS-C) and age-matched healthy controls. Strain was correlated with LV ejection fraction (EF) and serum troponin levels. RESULTS/UNASSIGNED:= 0.002) and troponin in patients with MIS-C. Abnormal strain persisted in one-third of patients in the MIS-C and acute COVID-19 groups on outpatient follow-up. CONCLUSIONS/UNASSIGNED:Patients with MIS-C and acute COVID-19 can develop myocardial dysfunction as seen by abnormal strain. LV longitudinal strain correlates with cardiac injury as measured by serum troponin in patients with MIS-C. Strain may provide an additional tool in detecting subtle myocardial dysfunction. It can be routinely employed at diagnosis and at follow-up evaluation of these patients.
PMID: 37152504
ISSN: 0974-2069
CID: 5544462