Long-Term Effects of COVID-19 on the Cardiopulmonary System in Adults and Children: Current Status and Questions to be Resolved by the National Institutes of Health Researching COVID to Enhance Recovery Initiative

TOPIC IMPORTANCE

Long COVID may occur in at least 10% of patients recovering from SARS-CoV-2 infection and often is associated with debilitating symptoms. Among the organ systems that might be involved in its pathogenesis, the respiratory and cardiovascular systems may be central to common symptoms seen in survivors of COVID-19, including fatigue, dyspnea, chest pain, cough, and exercise intolerance. Understand the exact symptomatology, causes, and effects of long COVID on the heart and lungs may help us to discover new therapies. To that end, the National Institutes of Health is sponsoring a national study population of diverse volunteers to support large-scale studies on the long-term effects of COVID-19.

REVIEW FINDINGS

The National Institutes of Health Researching COVID to Enhance Recovery (RECOVER) initiative currently is recruiting participants in the United States to answer critical questions about long COVID. The study comprises adult and pediatric cohorts as well as an electronic health record cohort. Based on symptoms, individuals undergo prespecified medical testing to understand whether abnormalities can be detected and are followed up longitudinally. Herein, we outline current understanding of the clinical symptoms and pathophysiologic features of long COVID with respect to the cardiopulmonary system in adults and children and then determine how the clinical, electronic health record, and autopsy cohorts of the RECOVER initiative will attempt to answer the most pressing questions surrounding the long-term effects of COVID-19.

SUMMARY

Data generated from the RECOVER initiative will provide guidance about missing gaps in our knowledge about long COVID and how they might be filled by data gathered through the RECOVER initiative.

Development of a Definition of Postacute Sequelae of SARS-CoV-2 Infection

Importance

SARS-CoV-2 infection is associated with persistent, relapsing, or new symptoms or other health effects occurring after acute infection, termed postacute sequelae of SARS-CoV-2 infection (PASC), also known as long COVID. Characterizing PASC requires analysis of prospectively and uniformly collected data from diverse uninfected and infected individuals.

Objective

To develop a definition of PASC using self-reported symptoms and describe PASC frequencies across cohorts, vaccination status, and number of infections.

Design, Setting, and Participants

Prospective observational cohort study of adults with and without SARS-CoV-2 infection at 85 enrolling sites (hospitals, health centers, community organizations) located in 33 states plus Washington, DC, and Puerto Rico. Participants who were enrolled in the RECOVER adult cohort before April 10, 2023, completed a symptom survey 6 months or more after acute symptom onset or test date. Selection included population-based, volunteer, and convenience sampling.

Exposure

SARS-CoV-2 infection.

Main Outcomes and Measures

PASC and 44 participant-reported symptoms (with severity thresholds).

Results

A total of 9764 participants (89% SARS-CoV-2 infected; 71% female; 16% Hispanic/Latino; 15% non-Hispanic Black; median age, 47 years [IQR, 35-60]) met selection criteria. Adjusted odds ratios were 1.5 or greater (infected vs uninfected participants) for 37 symptoms. Symptoms contributing to PASC score included postexertional malaise, fatigue, brain fog, dizziness, gastrointestinal symptoms, palpitations, changes in sexual desire or capacity, loss of or change in smell or taste, thirst, chronic cough, chest pain, and abnormal movements. Among 2231 participants first infected on or after December 1, 2021, and enrolled within 30 days of infection, 224 (10% [95% CI, 8.8%-11%]) were PASC positive at 6 months.

Conclusions and Relevance

A definition of PASC was developed based on symptoms in a prospective cohort study. As a first step to providing a framework for other investigations, iterative refinement that further incorporates other clinical features is needed to support actionable definitions of PASC.

Donor heart selection: Evidence-based guidelines for providers

The proposed donor heart selection guidelines provide evidence-based and expert-consensus recommendations for the selection of donor hearts following brain death. These recommendations were compiled by an international panel of experts based on an extensive literature review.

New insights into resting and exertional right ventricular performance in the healthy heart through real-time pressure-volume analysis

KEY POINTS

Despite growing interest in right ventricular form and function in diseased states, there is a paucity of data regarding characteristics of right ventricular function - namely contractile and lusitropic reserve, as well as ventricular-arterial coupling, in the healthy heart during rest, as well as submaximal and peak exercise. Pressure-volume analysis of the right ventricle, during invasive cardiopulmonary exercise testing, demonstrates that that the right heart has enormous contractile reserve, with a three- or fourfold increase in all metrics of contractility, as well as myocardial energy production and utilization. The healthy right ventricle also demonstrates marked augmentation in lusitropy, indicating that diastolic filling of the right heart is not passive. Rather, the right ventricle actively contributes to venous return during exercise, along with the muscle pump. Ventricular-arterial coupling is preserved during submaximal and peak exercise in the healthy heart.

ABSTRACT

Knowledge of right ventricular (RV) function has lagged behind that of the left ventricle and historically, the RV has even been referred to as a 'passive conduit' of lesser importance than its left-sided counterpart. Pressure-volume (PV) analysis is the gold standard metric of assessing ventricular performance. We recruited nine healthy sedentary individuals free of any cardiopulmonary disease (42 ± 12 years, 78 ± 11 kg), who completed invasive cardiopulmonary exercise testing during upright ergometry, while using conductance catheters inserted into the RV to generate real-time PV loops. Data were obtained at rest, two submaximal levels of exercise below ventilatory threshold, to simulate real-world scenarios/activities of daily living, and maximal effort. Breath-by-breath oxygen uptake was determined by indirect calorimetry. During submaximal and peak exercise, there were significant increases in all metrics of systolic function by three- to fourfold, including cardiac output, preload recruitable stroke work, and maximum rate of pressure change in the ventricle (dP/dtmax ), as well as energy utilization as determined by stroke work and pressure-volume area. Similarly, the RV demonstrated a significant, threefold increase in lusitropic reserve throughout exercise. Ventricular-arterial coupling, defined by the quotient of end-systolic elastance and effective arterial elastance, was preserved throughout all stages of exercise. Maximal pressures increased significantly during exercise, while end-diastolic volumes were essentially unchanged. Overall, these findings demonstrate that the healthy RV is not merely a passive conduit, but actively participates in cardiopulmonary performance during exercise by accessing an enormous amount of contractile and lusitropic reserve, ensuring that VA coupling is preserved throughout all stages of exercise.

Heart Failure With Preserved Ejection Fraction and Diabetes: JACC State-of-the-Art Review

Heart failure with preserved ejection fraction (HFpEF) is now the most common form of HF, affecting over 3 million adults in the United States alone. HFpEF is a heterogenous syndrome. One important phenotype may be related to comorbid conditions, including diabetes mellitus (DM). DM has a prevalence of approximately 45% in HFpEF, but characteristics and outcomes of this population are poorly understood. In this review, the authors summarize data from several clinical trials of HFpEF therapeutics and provide original data from a large cohort using the Get With The Guidelines-HF registry, which together suggest that DM is associated with increased morbidity and long-term mortality in HFpEF. The authors then discuss several common pathological mechanisms in HFpEF and DM, including sodium retention, metabolic derangements, impaired skeletal muscle function, and potential therapeutic targets. As the understanding of comorbid HFpEF and DM improves, it is hoped clinicians will be better equipped to offer effective, patient-centered treatments.

Zinc responsive dermatopathy in goats: two field cases

Two adult female goats presented with symmetrical alopecia, rough hair coats, weight loss, and generalized unthriftiness. In light of the history and clinical signs, we suspected a mineral deficiency or endocrine imbalance. These animals were being fed a diet of alfalfa, a legume high in calcium, which can block zinc uptake. Serum zinc levels were low, and skin biopsies supported the diagnosis of zinc deficiency. Therefore, these findings suggest that the main factor blocking zinc absorption was increased dietary calcium.

Imaging the brachial plexus and peripheral nerves in infants and children

Imaging of the brachial plexus and peripheral nerves is challenging in the pediatric patient. Magnetic resonance imaging is the modality of choice as it is not invasive and demonstrates proximal and distal lesions. This may be used to detect nerve root avulsions, nerve ruptures, pseudo-meningoceles, brachial plexus scarring, post-traumatic neuromas, brachial plexus edema, spinal cord damage, abnormalities of the shoulder joint, trauma, neoplasms, and infection. Imaging allows diagnosis and careful preoperative evaluation of children suffering from brachial plexus injuries and peripheral nerve disorders.

Molecular analysis of the 18S rRNA gene of Cryptosporidium serpentis in a wild-caught corn snake (Elaphe guttata guttata) and a five-species restriction fragment length polymorphism- based assay that can additionally discern C. parvum from C. wrairi

An adult wild-caught corn snake (Elaphe guttata guttata) was presented for humane euthanasia and necropsy because of severe cryptosporidiosis. The animal was lethargic and >5% dehydrated but in good flesh. Gastric lavage was performed prior to euthanasia. Histopathologic findings included gastric mucosal hypertrophy and a hemorrhagic erosive gastritis. Numerous 5- to 7-microm-diameter round extracellular organisms were associated with the mucosal hypertrophy. A PCR, acid-fast stains, Giemsa stains, and an enzyme immunoassay were all positive for Cryptosporidium spp. PCR and restriction fragment length polymorphism (RFLP) analysis on gastric lavage and gastric mucosal specimens, and subsequent sequencing of the 18S rRNA gene, enabled a distinct molecular characterization of the infecting organism as Cryptosporidium serpentis. Until recently, studies on snake Cryptosporidium have relied on host specificity and gross and histopathologic observations to identify the infecting species. A multiple alignment of our sequence against recently published sequences of the 18S rRNA gene of C. serpentis (GenBank accession no. AF093499, AF093500, and AF093501 [L. Xiao et al., unpublished data, 1998]) revealed 100% homology with the C. serpentis (Snake) sequence (AF093499) previously described by Xiao et al. An RFLP method to differentiate the five presently sequenced strains of Cryptosporidium at this locus was developed. This assay, which uses SpeI and SspI, complements a previously reported assay by additionally distinguishing the bovine strain of Cryptosporidium from Cryptosporidium wrairi.

Diffuse cerebral vasospasm with ischemia after resection of a cerebellopontine angle primitive neuroectodermal tumor in a child

This case report describes a 15-month-old female who developed diffuse cerebral vasospasm after resection of a cerebellopontine angle primitive neuroectodermal tumor. The patient developed an acute dense left hemiparesis 16 days postoperatively with partial right ptosis. Initial magnetic resonance imaging and diffusion study were unremarkable, though a magnetic resonance angiography 1 day later demonstrated severe intracranial vasospasm of both carotid and vertebral arteries. The vasospasm was confirmed with cerebral angiography. The patient progressed to bihemispheric infarcts with laminar necrosis despite combination therapy with anticoagulation, pharmacological hypertension, hypervolemia, and nimodipine. The clinical course, radiographic, and pathological findings are presented.

Cerebral aneurysmal arteriopathy in childhood AIDS

OBJECTIVE

To identify cerebral aneurysmal arteriopathy in children with longstanding AIDS.

BACKGROUND

Five cases are described from the authors' experience, and eight additional cases are reviewed from the literature. Details are presented in regard to the clinical picture as well as brain imaging with cerebral angiography and magnetic resonance angiography in some cases. Autopsy information is available in four cases, including one of the authors' patients.

RESULTS

Seven patients acquired HIV infection perinatally, five patients were infected by blood transfusions, and one patient had both risk factors. In the four postmortem patients, the vascular pathology was similar, showing ectasia and aneurysmal dilatation confined to the large arteries of the circle of Willis. Medial fibrosis and loss of muscularis with destruction of the internal elastic lamina and intimal hyperplasia was common. The latency period following infection varied from 2 to 11 years. Once a diagnosis of aneurysmal arteriopathy was made, the patients deteriorated rapidly, with death occurring in less than 6 months.

CONCLUSIONS

The development of cerebral aneurysmal arteriopathy in childhood AIDS tends to occur after a prolonged delay and is usually followed by death in a short period of time. The etiology for the vasculitis is unknown. Varicella zoster virus may be the etiology in some of the cases because of its potential to cause this pathology and the striking unilateral arterial involvement found in Case 5. HIV vasculitis is also a possibility, as suggested by the detection of HIV protein or genomic material in two of the four autopsy cases.

Epilepsy surgery in the first three years of life

PURPOSE

Partial seizures in early postnatal life may be catastrophic and associated with poor long-term outcome. Epilepsy surgery can alleviate partial seizures in older children and adults, but there is little experience with surgical therapy in infancy apart from hemispheric epilepsy syndromes.

METHODS

We analyzed the results of cortical resection to treat medically refractory partial epilepsy in 31 children (16 boys, 15 girls) aged <3 years (mean, 18.3 months). Subjects were included only if seizure relief was the primary indication for surgery.

RESULTS

Follow-up of at least 1 year (mean, 4.6 years) in 26 patients revealed that 16 were seizure-free, 4 had >90% seizure reduction, and 6 had <90% reduction. There was no significant difference in seizure outcome between hemispherectomy/multilobar resections and lobar resections or temporal versus extratemporal resection. Seizure outcome was independent of the amount of cortex removed in nonlesional patients. Only the presence of a discrete lesion on preoperative neuroimaging correlated with a favorable outcome. Family perceptions of accelerated development in seizure-free patients were not confirmed on developmental assessment.

CONCLUSIONS

We conclude that cortical resection often benefits very young children with catastrophic partial seizures, but does not guarantee enhanced neurological development. The location and extent of the excised cortex may not be critical as long as the entire epileptogenic region and lesion are removed.

Bilateral aplasia of the optic nerves, chiasm, and tracts in an otherwise healthy infant

PURPOSE

To report bilateral aplasia of the optic nerves, chiasm, and tracts in an otherwise healthy infant.

METHOD

Case report.

RESULTS

Ophthalmologic examination disclosed bilateral microphthalmos and optic nerve aplasia. Physical, neurologic, and genetic evaluations were otherwise normal. Magnetic resonance imaging of the brain and orbits disclosed bilateral aplasia of the optic nerves, chiasm, and tracts.

CONCLUSION

Bilateral aplasia of the optic nerves, chiasm, and tracts may occur in an otherwise healthy infant.

Preoperative clinical, EEG, and imaging findings do not predict seizure outcome following temporal lobectomy in childhood

Although certain clinical, electroencephalographic (EEG), magnetic resonance imaging (MRI), and pathologic findings in adults with intractable temporal lobe epilepsy predict seizure outcome following temporal lobectomy, predictors of seizure outcome have not been studied systematically in pediatric temporal lobectomy series. We retrospectively analyzed preoperative clinical, EEG, and neuroimaging findings with reference to seizure outcome (seizure free or non-seizure free) in 33 children (mean age, 9.3 years) who underwent tailored temporal lobe resections for intractable temporal lobe epilepsy. Trends were apparent with (1) younger age at seizure onset, younger age at surgery, shorter duration of epilepsy, localized unilateral temporal lesions on MRI, and right-sided surgery more frequently associated with a seizure-free outcome, and (2) significant prior history, daily preoperative seizures, generalized motor seizures, mental retardation, and localized unilateral temporal epileptiform EEG activity more frequently associated with a non-seizure-free outcome. However, none of these findings, alone or in combination, correlated with postoperative seizure status at a statistically significant level. Submitting the four variables generally considered to be most predictive of favorable outcome (ie, normal intelligence, unilateral ictal and interictal EEG discharges, and focal temporal MRI lesion) to a multiple-cutoff procedure did not predict seizure freedom. Our data indicate that predictors of outcome of temporal lobectomy in adults may not apply in children, perhaps due to inherent neurobiologic differences in the etiology and expression of temporal lobe epilepsy, and should therefore not be used as sole determinants of surgical candidacy in children.

Hemifacial seizures and cerebellar ganglioglioma: an epilepsy syndrome of infancy with seizures of cerebellar origin

We investigated a 6-month-old infant with daily episodes of left hemifacial contraction, head and eye deviation to the right, nystagmoid jerks to the right, autonomic dysfunction, and retained consciousness. The episodes began on day 1 of life and were unresponsive to antiepileptic medication. Interictal and ictal scalp electroencephalographic (EEG) recordings were unremarkable. Magnetic resonance imaging revealed a mass in the left cerebellar hemisphere and peduncle. Ictal single-photon emission computed tomography revealed focal hyperperfusion in the region of the cerebellar mass. Ictal EEG recordings with implanted cerebellar electrodes demonstrated focal seizure discharges in the region of the mass. Resection of the mass resulted in remission of seizures and histopathology revealed ganglioglioma. Six previously reported infants with similar semiology (described as "hemifacial spasm"), imaging findings, and histopathology are reviewed. We believe the previously reported infants and our patient constitute a rare but important clinicopathological syndrome of infancy characterized by epileptic seizures of cerebellar origin.

The developing cerebral surface. Preliminary report on the patterns of sulcal and gyral maturation--anatomy, ultrasound, and magnetic resonance imaging

This literature review provides data on the temporal sequence in which gyri, sulci, and fissures first become apparent on anatomic specimens of the developing brain surface. Ultrasonic display of these anatomic features lags behind the initial appearance of the features by a variable interval, greater in early gestation and diminishing in late gestation. MR imaging, especially three-dimensional surface rendering, displays the degree of surface maturation to advantage. Different publications have provided variable estimates of the time course of surface maturation, leading to discordance in the date tabulated. None-the-less, the overall sequence is clear and the surface features are useful in assessing the degree of fetal-neonatal maturity by ultrasonography and by MR imaging.

Cross-validation of cyanogen bromide-peptide ratios to measure the proportion of type II collagen in pepsin digests of equine articular cartilage, meniscus, and cartilage repair tissue

Collagen type I and type II were purified from equine flexor tendon and articular cartilage, respectively. Equal amounts of these collagens were cleaved with cyanogen bromide, and 11 mixtures containing increasing proportions of type II collagen were separated in seven identical sodium dodecyl sulfate-polyacrylamide gels. The density of bands was measured in wet gels and the peak areas were used to form six ratios of peptide bands that had polynomial relationships with the known proportions of type I and type II collagen in the mixtures. Calibration curves for determining the proportion of type II collagen in the mixtures were constructed using ratios and combinations of ratios of peak areas. Cross-validation was used to identify calibration curves with the smallest squared prediction error or squared average prediction error for all combinations of ratios. Ratios of peak areas of each one of the seven gels were treated, in turn, as the "unknown," and a prediction was carried out using these unknowns and the ratios from the other six gels. Two ratios had the smallest squared average prediction error and calibration curves were computed for these ratios with all seven gels. These curves were used to estimate the proportion of type II collagen in the pepsin-soluble and the pepsin-resistant fractions of articular cartilage inner and outer meniscus, and cartilage repair tissue. Cross-validation enabled selection of the cyanogen bromide-peptide ratios for calibration curves that resulted in the most accurate estimation of the proportion of type II collagen in pepsin digests of tissues.