How Does COVID-19 Affect the Heart?

PURPOSE OF REVIEW: Cardiac consequences occur in both acute COVID-19 and post-acute sequelae of COVID-19 (PASC). Here, we highlight the current understanding about COVID-19 cardiac effects, based upon clinical, imaging, autopsy, and molecular studies. RECENT FINDINGS: COVID-19 cardiac effects are heterogeneous. Multiple, concurrent cardiac histopathologic findings have been detected on autopsies of COVID-19 non-survivors. Microthrombi and cardiomyocyte necrosis are commonly detected. Macrophages often infiltrate the heart at high density but without fulfilling histologic criteria for myocarditis. The high prevalences of microthrombi and inflammatory infiltrates in fatal COVID-19 raise the concern that recovered COVID-19 patients may have similar but subclinical cardiac pathology. Molecular studies suggest that SARS-CoV-2 infection of cardiac pericytes, dysregulated immunothrombosis, and pro-inflammatory and anti-fibrinolytic responses underlie COVID-19 cardiac pathology. The extent and nature by which mild COVID-19 affects the heart is unknown. Imaging and epidemiologic studies of recovered COVID-19 patients suggest that even mild illness confers increased risks of cardiac inflammation, cardiovascular disorders, and cardiovascular death. The mechanistic details of COVID-19 cardiac pathophysiology remain under active investigation. The ongoing evolution of SARS-CoV-2 variants and vast numbers of recovered COVID-19 patients portend a burgeoning global cardiovascular disease burden. Our ability to prevent and treat cardiovascular disease in the future will likely depend on comprehensive understanding of COVID-19 cardiac pathophysiologic phenotypes.

Noninvasive Physiologic Assessment of Cardiac Allograft Vasculopathy Is Prognostic for Post-Transplant Events.

BACKGROUND: Cardiac allograft vasculopathy (CAV) causes impaired blood flow in both epicardial coronary arteries and the microvasculature. A leading cause of post-transplant mortality, CAV affects 50% of heart transplant recipients within 10 years of heart transplant. OBJECTIVES: This analysis examined the outcomes of heart transplant recipients with reduced myocardial blood flow reserve (MBFR) and microvascular CAV detected by 13N-ammonia positron emission tomography (PET) myocardial perfusion imaging. METHODS: A total of 181 heart transplant recipients who underwent PET to assess for CAV were included with a median follow-up of 4.7 years. Patients were classified into 2 groups according to the total MBFR: >2.0 and ≤2.0. Microvascular CAV was defined as no epicardial CAV detected by PET and/or coronary angiography, but with an MBFR ≤2.0 by PET. RESULTS: In total, 71 (39%) patients had an MBFR ≤2.0. Patients with an MBFR ≤2.0 experienced an increased risk for all outcomes: 7-fold increase in death or retransplantation (HR: 7.05; 95% CI: 3.2-15.6; P < 0.0001), 12-fold increase in cardiovascular death (HR: 12.0; 95% CI: 2.64-54.12; P = 0.001), and 10-fold increase in cardiovascular hospitalization (HR: 10.1; 95% CI: 3.43-29.9; P < 0.0001). The 5-year mean survival was 302 days less than those with an MBFR >2.0 (95% CI: 260.2-345.4 days; P < 0.0001). Microvascular CAV (adjusted HR: 3.86; 95% CI: 1.58-9.40; P = 0.003) was independently associated with an increased risk of death or retransplantation. CONCLUSIONS: Abnormal myocardial blood flow reserve, even in the absence of epicardial CAV, identifies patients at a high risk of death or retransplantation. Measures of myocardial blood flow provide prognostic information in addition to traditional CAV assessment.

COVID-19 and Cardiovascular Disease.

Coronavirus disease 2019 (COVID-19) is a global pandemic affecting 185 countries and >3 000 000 patients worldwide as of April 28, 2020. COVID-19 is caused by severe acute respiratory syndrome coronavirus 2, which invades cells through the angiotensin-converting enzyme 2 receptor. Among patients with COVID-19, there is a high prevalence of cardiovascular disease, and >7% of patients experience myocardial injury from the infection (22% of critically ill patients). Although angiotensin-converting enzyme 2 serves as the portal for infection, the role of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers requires further investigation. COVID-19 poses a challenge for heart transplantation, affecting donor selection, immunosuppression, and posttransplant management. There are a number of promising therapies under active investigation to treat and prevent COVID-19.

Understanding the Link Between Obesity and Severe COVID-19 Outcomes: Causal Mediation by Systemic Inflammatory Response.

BACKGROUND: Obesity is an established risk factor for severe COVID-19 outcomes. The mechanistic underpinnings of this association are not well-understood. OBJECTIVE: To evaluate the mediating role of systemic inflammation in obesity-associated COVID-19 outcomes. METHODS: This hospital-based, observational study included 3828 SARS-CoV-2-infected patients who were hospitalized February to May 2020 at Massachusetts General Hospital (MGH) or Columbia University Irving Medical Center/New York Presbyterian Hospital (CUIMC/NYP). We use mediation analysis to evaluate whether peak inflammatory biomarkers (C-reactive protein [CRP], erythrocyte sedimentation rate [ESR], D-dimer, ferritin, white blood cell count and interleukin-6) are in the causal pathway between obesity (BMI ≥ 30) and mechanical ventilation or death within 28 days of presentation to care. RESULTS: In the MGH cohort (n = 1202), obesity was associated with greater likelihood of ventilation or death (OR = 1.73; 95% CI = [1.25, 2.41]; P = 0.001) and higher peak CRP (P < 0.001) compared with nonobese patients. The estimated proportion of the association between obesity and ventilation or death mediated by CRP was 0.49 (P < 0.001). Evidence of mediation was more pronounced in patients < 65 years (proportion mediated = 0.52 [P < 0.001] vs 0.44 [P = 0.180]). Findings were more moderate but consistent for peak ESR. Mediation by other inflammatory markers was not supported. Results were replicated in CUIMC/NYP cohort (n = 2626). CONCLUSION: Findings support systemic inflammatory pathways in obesity-associated severe COVID-19 disease, particularly in patients < 65 years, captured by CRP and ESR. Contextualized in clinical trial findings, these results reveal therapeutic opportunity to target systemic inflammatory pathways and monitor interventions in high-risk subgroups and particularly obese patients.

Admission Cardiac Diagnostic Testing with Electrocardiography and Troponin Measurement Prognosticates Increased 30-Day Mortality in COVID-19.

Background Cardiovascular involvement in coronavirus disease 2019 (COVID-19) is common and leads to worsened mortality. Diagnostic cardiovascular studies may be helpful for resource appropriation and identifying patients at increased risk for death. Methods and Results We analyzed 887 patients (aged 64±17 years) admitted with COVID-19 from March 1 to April 3, 2020 in New York City with 12 lead electrocardiography within 2 days of diagnosis. Demographics, comorbidities, and laboratory testing, including high sensitivity cardiac troponin T (hs-cTnT), were abstracted. At 30 days follow-up, 556 patients (63%) were living without requiring mechanical ventilation, 123 (14%) were living and required mechanical ventilation, and 203 (23%) had expired. Electrocardiography findings included atrial fibrillation or atrial flutter (AF/AFL) in 46 (5%) and ST-T wave changes in 306 (38%). 27 (59%) patients with AF/AFL expired as compared to 181 (21%) of 841 with other non-life-threatening rhythms (P<0.001). Multivariable analysis incorporating age, comorbidities, AF/AFL, QRS abnormalities, and ST-T wave changes, and initial hs-cTnT ≥20 ng/L showed that increased age (HR 1.04/year), elevated hs-cTnT (HR 4.57), AF/AFL (HR 2.07), and a history of coronary artery disease (HR 1.56) and active cancer (HR 1.87) were associated with increased mortality. Conclusions Myocardial injury with hs-cTnT ≥20 ng/L, in addition to cardiac conduction perturbations, especially AF/AFL, upon hospital admission for COVID-19 infection is associated with markedly increased risk for mortality than either diagnostic abnormality alone.

Pharmacological Agents Targeting Thromboinflammation in COVID-19: Review and Implications for Future Research.

Coronavirus disease 2019 (COVID-19), currently a worldwide pandemic, is a viral illness caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The suspected contribution of thrombotic events to morbidity and mortality in COVID-19 patients has prompted a search for novel potential options for preventing COVID-19-associated thrombotic disease. In this article by the Global COVID-19 Thrombosis Collaborative Group, we describe novel dosing approaches for commonly used antithrombotic agents (especially heparin-based regimens) and the potential use of less widely used antithrombotic drugs in the absence of confirmed thrombosis. Although these therapies may have direct antithrombotic effects, other mechanisms of action, including anti-inflammatory or antiviral effects, have been postulated. Based on survey results from this group of authors, we suggest research priorities for specific agents and subgroups of patients with COVID-19. Further, we review other agents, including immunomodulators, that may have antithrombotic properties. It is our hope that the present document will encourage and stimulate future prospective studies and randomized trials to study the safety, efficacy, and optimal use of these agents for prevention or management of thrombosis in COVID-19.

Characteristics and Outcomes of Recipients of Heart Transplant With Coronavirus Disease 2019.

Importance: Recipients of heart transplant (HT) may be at increased risk of adverse outcomes attributable to infection with coronavirus disease 2019 (COVID-19) because of multiple comorbidities and clinically significant immunosuppression. Objective: To describe the characteristics, treatment, and outcomes of recipients of HT with COVID-19. Design, Setting, and Participants: This case series from a single large academic heart transplant program in New York, New York, incorporates data from between March 1, 2020, and April 24, 2020. All recipients of HT followed up by this center who were infected with COVID-19 were included. Interventions: Heart transplant and a confirmed diagnosis of COVID-19. Main Outcomes and Measures: The primary measure was vital status at end of study follow-up. Secondary measures included patient characteristics, laboratory analyses, changes to immunosuppression, and treatment administered for COVID-19. Results: Twenty-eight patients with HT received a confirmed diagnosis of COVID-19. The median age was 64.0 (interquartile range [IQR], 53.5-70.5) years, 22 (79%) were men, and the median time from HT was 8.6 (IQR, 4.2-14.5) years. Comorbid conditions included hypertension in 20 patients (71%), diabetes in 17 patients (61%), and cardiac allograft vasculopathy in 16 patients (57%). Twenty-two participants (79%) were admitted for treatment, and 7 (25%) required mechanical ventilation. Most (13 of 17 [76%]) had evidence of myocardial injury (median high-sensitivity troponin T, 0.055 [IQR, 0.0205-0.1345] ng/mL) and elevated inflammatory biomarkers (median peak high-sensitivity C-reactive protein, 11.83 [IQR, 7.44-19.26] mg/dL; median peak interleukin 6, 105 [IQR, 38-296] pg/mL). Among patients managed at the study institution, mycophenolate mofetil was discontinued in 16 patients (70%), and 6 (26%) had a reduction in the dose of their calcineurin inhibitor. Treatment of COVID-19 included hydroxychloroquine (18 patients [78%]), high-dose corticosteroids (8 patients [47%]), and interleukin 6 receptor antagonists (6 patients [26%]). Overall, 7 patients (25%) died. Among 22 patients (79%) who were admitted, 11 (50%) were discharged home, 4 (18%) remain hospitalized at the end of the study, and 7 (32%) died during hospitalization. Conclusions and Relevance: In this single-center case series, COVID-19 infection was associated with a case fatality rate of 25% in recipients of HT. Immunosuppression was reduced in most of this group of patients. Further study is required to evaluate the optimal approach to management of COVID-19 infection in the HT population.