474 A case of Takotsubo cardiomyopathy in SARS-CoV-2 infection

Cardiovascular complications are a frequent occurrence in SARS-CoV-2 infection. Takotsubo cardiomyopathy (also known as stress cardiomyopathy) is a possible cause of transient ST segment elevation (1–3% of total cases) and is characterized by a reversible left ventricular dysfunction with coronary arteries free from critical stenosis. The predominant echocardiographic pattern of this cardiomyopathy is an akinesia of the mid-apical myocardial segments (‘apical ballooning’), with preserved kinetics of the basal segments. The incidence of Takotsubo cardiomyopathy showed a marked increase during the COVID-19 pandemic. The data showed that three factors mainly contribute to the onset of cardiomyopathy in patients with COVID-19: cytokine storm, adrenergic hyperactivation and microvascular dysfunction. A 79-year-old woman was hospitalized in the Pneumology department of our hospital for acute hypoxemic respiratory failure due to bilateral interstitial pneumonia SARS-CoV-2 related. In remote medical history: in 2010 diagnosis of breast cancer, treated with quadrantectomy, adjuvant chemo- and radiotherapy, with negative follow-up for disease recovery, systemic arterial hypertension, hypercholesterolaemia and from 2016 syndrome of reduced mobility as a result of a previous ischaemic stroke. Non-invasive mechanical ventilation with c-PAP was started in the ward and, for the detection of anterolateral electrocardiographic anomalies (diffuse symmetrical negative T waves. Figure) and an increase in myocardionecrosis markers (troponin I peak: 5.4 ng/ml), in the absence of chest pain or equivalent, echocardiographic evaluation was performed, which revealed an akinesia of the mid-apical segments of the left ventricle with preserved kinetics of the basal segments and severely depressed global systolic function (ejection fraction: 30%). BNP (18.100 pg/ml), interleukin-6 (339 pg/ml), and CRP (136 mg/l) were elevated on blood chemistry tests. In the suspicion of Takotsubo cardiomyopathy (InterTAK Score: 67, probability: 79.8%), cardioprotective therapy with ACE inhibitor, beta-blocker, diuretics, low molecular weight heparin, double antiaggregation, and statin was started, deferring coronary angiography to improve clinical conditions. In the following days, due to the respiratory and haemodynamic worsening, the patient was transferred to an intensive setting, where she was intubated and treated with levosimendan and noradrenaline. In the intensive care unit, serial echocardiograms (over 30 days) showed a progressive improvement, up to normalization, of the global systolic function (ejection fraction at the last checkup: 55%), with complete regression of the kinetic anomalies, confirming the diagnostic hypothesis of stress cardiomyopathy. For a pulmonary mycotic superinfection (positive bronchoaspirate for Candida albicans and Candida krusei), complicated by iatrogenic pneumothorax, in the following days the patient died.

Haemophagocytic lymphohistiocytosis (HLH)-associated stress cardiomyopathy secondary to autoimmune conditions successfully treated with anakinra

We describe two young cases of reactive haemophagocytic lymphohistiocytosis (HLH) with the resultant stress cardiomyopathy in the setting of underlying autoimmune diseases, systemic lupus erythematosus (SLE) and Still’s disease. The initial presentation was similar in both cases with fever, hyperinflammatory response, hypotension (vasoplegia), bicytopenia and hyperferritinemia. Despite standard of care and multiple broad-spectrum antibiotics, both cases remained pyrexic and were ultimately admitted to the intensive therapy unit to treat cardiogenic shock. Echocardiogram of both cases showed low ejection fraction, the cause for which was not found until the final diagnosis of HLH was made. Both cases made a complete clinical and cardiac recovery following the initiation of high-dose glucocorticoids and anakinra.

A review of COVID-19 vaccination and the reported cardiac manifestations

In Singapore, 9.03 million doses of the mRNA COVID-19 vaccines by Pfizer-BioNTech and Moderna have been administered, and 4.46 million people are fully vaccinated. An additional 87,000 people have been vaccinated with vaccines in World Health Organization’s Emergency Use Listing. The aim of this review is to explore the reported cardiac adverse events associated with different types of COVID-19 vaccines. 42 studies that reported cardiac side effects after COVID-19 vaccination were included in this study. Reported COVID-19 vaccine-associated cardiac adverse events were mainly myocarditis and pericarditis, most commonly seen in adolescent and young adult male individuals after mRNA vaccination. Reports of other events such as acute myocardial infarction, arrhythmia and stress cardiomyopathy were rare. Outcomes of post-vaccine myocarditis and pericarditis were good. Given the good vaccine efficacy and the high number of cases of infection, hospitalisation and death that could potentially be prevented, COVID-19 vaccine remains of overall benefit, based on the current available data.

The role of the autonomic nervous system in stress cardiomyopathy

Aim. To identify the role of the autonomic nervous system in stress cardiomyopathy in an experimental model of Takotsubo syndrome.Materials and methods. The study was carried out on 120 female Wistar rats. Stress modeling was performed by immobilizing animals on the back for 24 hours. Intact rats were used as controls. The rats were decapitated after termination of immobilization under general anesthesia with ether. Stress cardiomyopathy (SCM) was quantified by accumulation of 99mTc pyrophosphate radiopharmaceutical (99mTc PP) in the myocardium. The pharmacological agents used included the ganglionic blocker hexamethonium, administered five times at a dose of 20 mg / kg; guanethidine (50 mg / kg) administered subcutaneously once a day for three days, the last injection was performed 24 hours before immobilization; the muscarinic receptor antagonist atropine methyl nitrate (1 mg / kg); the α1-AR (adrenergic receptor) antagonist prazosin (2 mg / kg); the α2-AR antagonist yohimbine, administered at a dose of 2 mg / kg; the β1-AR antagonist nebivolol (1.2 mg / kg); the β2-AR antagonist ICI 118,551 (0.3 mg / kg); and the β3-AR antagonist L-748337 (0.1 mg / kg).Results. Three-day administration of guanethidine caused a decrease in the degree of 99mTc-PP accumulation in the heart by 35.9%. Hexamethonium did not affect the degree of SCM. The blockade of the muscarinic receptor caused an increase in accumulation of 99mTc-PP by 26.5%. Inhibition of α1-AR did not affect SCM. The blockade of α2-AR caused a 2.2-fold increase in the accumulation compared with stress control. The blockade of β1-AR reduced 99mTc-PP accumulation by 2.5 times. The blockade of β2-AR by ICI 118,551 increased the degree of 99mTcPP accumulation by 34.6%. Inhibition of β3-AR had no effect on SCM.Conclusion. The adrenergic system and β1-adrenergic receptor play an important role in the development of SCM. The parasympathetic nervous system ensures resistance of the heart to stress.