Vaccination-Associated Myocarditis and Myocardial Injury

SARS-CoV-2 vaccine-associated myocarditis/myocardial injury should be evaluated in the contexts of COVID-19 infection, other types of viral myocarditis, and other vaccine-associated cardiac disorders. COVID-19 vaccine-associated myocardial injury can be caused by an inflammatory immune cell infiltrate, but other etiologies such as microvascular thrombosis are also possible. The clinical diagnosis is typically based on symptoms and cardiac magnetic resonance imaging. Endomyocardial biopsy is confirmatory for myocarditis, but may not show an inflammatory infiltrate because of rapid resolution or a non-inflammatory etiology. Myocarditis associated with SARS-COVID-19 vaccines occurs primarily with mRNA platform vaccines, which are also the most effective. In persons aged >16 or >12 years the myocarditis estimated crude incidences after the first 2 doses of BNT162b2 and mRNA-1273 are approximately 1.9 and 3.5 per 100 000 individuals, respectively. These rates equate to excess incidences above control populations of approximately 1.2 (BNT162b2) and 1.9 (mRNA-1273) per 100 000 persons, which are lower than the myocarditis rate for smallpox but higher than that for influenza vaccines. In the studies that have included mRNA vaccine and SARS-COVID-19 myocarditis measured by the same methodology, the incidence rate was increased by 3.5-fold over control in COVID-19 compared with 1.5-fold for BNT162b2 and 6.2-fold for mRNA-1273. However, mortality and major morbidity are less and recovery is faster with mRNA vaccine-associated myocarditis compared to COVID-19 infection. The reasons for this include vaccine-associated myocarditis having a higher incidence in young adults and adolescents, typically no involvement of other organs in vaccine-associated myocarditis, and based on comparisons to non-COVID viral myocarditis an inherently more benign clinical course.

Myocardial Injury and Altered Gene Expression Associated With SARS-CoV-2 Infection or mRNA Vaccination

SARS CoV-2 enters host cells via its Spike protein moiety binding to the essential cardiac enzyme angiotensin-converting enzyme (ACE) 2, followed by internalization. COVID-19 mRNA vaccines are RNA sequences that are translated into Spike protein, which follows the same ACE2-binding route as the intact virion. In model systems, isolated Spike protein can produce cell damage and altered gene expression, and myocardial injury or myocarditis can occur during COVID-19 or after mRNA vaccination. We investigated 7 COVID-19 and 6 post-mRNA vaccination patients with myocardial injury and found nearly identical alterations in gene expression that would predispose to inflammation, coagulopathy, and myocardial dysfunction.

Allergy and the Heart: Eosinophilic Myocarditis With Biventricular Thrombi

A 40-year-old woman with history of atopy and peripheral eosinophilia presented with clinical signs of heart failure. Echocardiography revealed a restrictive cardiomyopathy with biventricular thrombi. Hypereosinophilic syndrome resulting in eosinophilic myocarditis (Loeffler’s syndrome) was diagnosed. This case highlights the workup, diagnosis, and management of hypereosinophilic syndrome with eosinophilic myocarditis. (Level of Difficulty: Advanced.)

Dynamic Regulation of SARS-Cov-2 Binding and Cell Entry Mechanisms in Remodeled Human Ventricular Myocardium

Using serial analysis of myocardial gene expression employing endomyocardial biopsy starting material in a dilated cardiomyopathy cohort, we show that mRNA expression of the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) cardiac myocyte receptor ACE2 is up-regulated with remodeling and with reverse remodeling down-regulates into the normal range. The proteases responsible for virus-cell membrane fusion were expressed but not regulated with remodeling. In addition, a new candidate for SARS-CoV-2 cell binding and entry was identified, the integrin encoded by ITGA5. Up-regulation in ACE2 in remodeled left ventricles may explain worse outcomes in patients with coronavirus disease 2019 who have underlying myocardial disorders, and counteracting ACE2 up-regulation is a possible therapeutic approach to minimizing cardiac damage.

Sequential analysis of myocardial gene expression with phenotypic change: Use of cross-platform concordance to strengthen biologic relevance

Objectives

To investigate the biologic relevance of cross-platform concordant changes in gene expression in intact human failing/hypertrophied ventricular myocardium undergoing reverse remodeling.

Background

Information is lacking on genes and networks involved in remodeled human LVs, and in the associated investigative best practices.

Methods

We measured mRNA expression in ventricular septal endomyocardial biopsies from 47 idiopathic dilated cardiomyopathy patients, at baseline and after 3–12 months of β-blocker treatment to effect left ventricular (LV) reverse remodeling as measured by ejection fraction (LVEF). Cross-platform gene expression change concordance was investigated in reverse remodeling Responders (R) and Nonresponders (NR) using 3 platforms (RT-qPCR, microarray, and RNA-Seq) and two cohorts (All 47 subjects (A-S) and a 12 patient “Super-Responder” (S-R) subset of A-S).

Results

For 50 prespecified candidate genes, in A-S mRNA expression 2 platform concordance (C_cpT), but not single platform change, was directly related to reverse remodeling, indicating C_cpT has biologic significance. Candidate genes yielded a C_cpT (PCR/microarray) of 62% for Responder vs. Nonresponder (R/NR) change from baseline analysis in A-S, and ranged from 38% to 100% in S-R for PCR/microarray/RNA-Seq 2 platform comparisons. Global gene C_cpT measured by microarray/RNA-Seq was less than for candidate genes, in S-R R/NR 17.5% vs. 38% (P = 0.036). For S-R global gene expression changes, both cross-cohort concordance (C_ccT) and C_cpT yielded markedly greater values for an R/NR vs. an R-only analysis (by 22 fold for C_ccT and 7 fold for C_cpT). Pathway analysis of concordant global changes for R/NR in S-R revealed signals for downregulation of multiple phosphoinositide canonical pathways, plus expected evidence of a β₁-adrenergic receptor gene network including enhanced Ca²⁺ signaling.

Conclusions

Two-platform concordant change in candidate gene expression is associated with LV biologic effects, and global expression concordant changes are best identified in an R/NR design that can yield novel information.

Intravenous Iron Therapy in Heart Failure

Iron deficiency anemia is both a comorbid condition and an indicator of poor prognosis in heart failure. The mechanisms by which this occurs are multiple and complex. Recent robust randomized clinical trials have shown significant improvements in quality of life and rates of hospitalization with intravenous repletion of iron. In this article, we review the mechanisms by which iron deficiency impacts heart failure and the evidence behind repletion. There remains a good deal to learn about long-term effects of intravenous iron repletion, and clinical trials are ongoing in this regard.

Structural and Functional Phenotyping of the Failing Heart: Is the Left Ventricular Ejection Fraction Obsolete?

Diagnosis, prognosis, treatment, and development of new therapies for diseases or syndromes depend on a reliable means of identifying phenotypes associated with distinct predictive probabilities for these various objectives. Left ventricular ejection fraction (LVEF) provides the current basis for combined functional and structural phenotyping in heart failure by classifying patients as those with heart failure with reduced ejection fraction (HFrEF) and those with heart failure with preserved ejection fraction (HFpEF). Recently the utility of LVEF as the major phenotypic determinant of heart failure has been challenged based on its load dependency and measurement variability. We review the history of the development and adoption of LVEF as a critical measurement of LV function and structure and demonstrate that, in chronic heart failure, load dependency is not an important practical issue, and we provide hemodynamic and molecular biomarker evidence that LVEF is superior or equal to more unwieldy methods of identifying phenotypes of ventricular remodeling. We conclude that, because it reliably measures both left ventricular function and structure, LVEF remains the best current method of assessing pathologic remodeling in heart failure in both individual clinical and multicenter group settings. Because of the present and future importance of left ventricular phenotyping in heart failure, LVEF should be measured by using the most accurate technology and methodologic refinements available, and improved characterization methods should continue to be sought.

Outcome of hepatitis B virus infection in homosexual men and its relation to prior human immunodeficiency virus infection

To investigate the effect of human immunodeficiency virus type 1 (HIV-1) infection on subsequent hepatitis B virus (HBV) infection, HIV antibody was sought in homosexual men who developed HBV infection during a hepatitis B vaccine trial. Among 134 unvaccinated HIV-1-negative men, 7% became HBV carriers, 64% had viremia, and 42% had clinical illness. Among vaccinated HIV-1-negative men, HBV infection severity decreased with number of vaccine doses administered. When adjusted for prior hepatitis B vaccination status, persons with HIV-1 infection preceding HBV infection had a significantly higher risk of developing HBV carriage, viremia, prolonged ALT elevation, and clinical illness. Among HIV-1-infected men, the risk of HBV carriage was increased in unvaccinated persons (21%) and those who failed to respond to vaccination (31%) and further increased in those who received vaccine doses at the time they developed new HBV infection (56%-80%), suggesting inactivated hepatitis B vaccine may temporarily impair the immune response to HBV infection in HIV-1-infected persons. HIV-1 infection was also associated with reduced alanine aminotransferase elevations during the first 36 months of follow-up of men who became HBV carriers.

Sexual behavior before AIDS: the hepatitis B studies of homosexual and bisexual men

Data on sexual practices, collected during studies of hepatitis B virus (HBV) infection in 1978 and 1979, were analyzed for 4910 homosexual and bisexual men from Chicago, Denver, Los Angeles, San Francisco, and St Louis. Data on sexual practices in 1978 showed that white participants had larger numbers of non-steady male sexual partners and engaged in oral-genital activities more frequently but were equally likely to engage in anal intercourse as black and Hispanic participants. San Francisco participants had more non-steady sex partners and were more likely to engage in receptive anal intercourse with non-steady partners than participants from all other sites. Analysis of data on 606 HBV-antibody-negative men interviewed on three occasions in 1978 and 1979 showed no changes in risk indices for insertive and receptive anal intercourse between these years, except in San Francisco where significant declines occurred in insertive anal intercourse and receptive anal intercourse without ejacultion in a small, highly select group of participants.

Delta hepatitis in homosexual men in the United States

To assess the incidence and prevalence of delta hepatitis in homosexual men, we tested serum specimens for delta markers in participants in two previous studies: a hepatitis B vaccine trial among homosexual men conducted in the early 1980's and the Centers for Disease Control sentinel counties hepatitis study for 1983-1984. In the vaccine trial, men found to be hepatitis B surface antigen positive at the time of enrollment and those men who had serologic evidence of new hepatitis B virus infection during follow-up were tested. In the sentinel counties study that determined risk factors for viral hepatitis in reported cases, all homosexual men with acute and chronic hepatitis B virus infections were tested for delta markers. Specimens were tested for delta antigen and IgM and total delta antibody. In seven different cities, among 321 men found to be HBsAg positive at the time of screening, eight (2%) were positive for any delta marker. Among 290 men with new hepatitis B virus infections during follow-up, three (two coinfections, one superinfection) had serologic evidence of delta hepatitis. In the sentinel counties study, 0/63 acute hepatitis B virus infections in homosexual men were associated with delta hepatitis. This study indicates that the delta agent is an infrequent cause of viral hepatitis in homosexual men in the United States.

Long-term immunogenicity and efficacy of hepatitis B vaccine in homosexual men

To study the duration of antibody persistence and protection provided by the hepatitis B vaccine, we followed 773 homosexual men for five years after completion of vaccination. Among the 635 participants in whom antibody levels above 9.9 sample ratio units (SRU) developed after vaccination, 15 percent lost antibody altogether, and in another 27 percent, antibody levels declined below 10 SRU within five years. The extent of the maximal antibody response strongly predicted the persistence of protective antibody. Hepatitis B infection occurred in 55 men; 8 of these infections were clinically important (characterized by the presence of the hepatitis B surface antigen and elevation of liver-enzyme levels), and two of the patients became hepatitis B virus carriers. The long-term risk of hepatitis B infection was inversely related to the maximal antibody response to vaccine. Most severe infections occurred among those who responded poorly or had no response to the vaccination. The risk of late infection with hepatitis B in those with an initially adequate vaccine response increased markedly when antibody levels decreased below 10 SRU, but only 1 of 34 late infections resulted in viremia and liver inflammation. A second series of vaccinations induced a moderate antibody response in 50 percent of the subjects who initially had no response or a poor response; however, the persistence of antibody was poor. Both antibody loss and the risk of severe disease should be considered when booster-dose strategies for the hepatitis B vaccine are being designed.

Sexually transmitted diseases and homosexuality

An epidemic of sexually transmitted diseases, culminating in the emergence of acquired immune-deficiency states, has developed among homosexually active men during the past ten to 15 years. This epidemic is reviewed in relation to causative factors, priorities for control, and recommendations for control and prevention. Causative factors are divided into physical, behavioral, cultural, and political factors. Given the complicated interactions of these factors and the numerous diseases epidemic in the homosexuality active population, priorities need to be established for research and control programs that take into account the overall health impact of each disease and the effectiveness of available and potential resources. Finally, educational programs must be developed that will overcome the limited effectiveness of public health control efforts in this area, or we may expect even more serious and widespread health care problems.