Heart failure represents one of the most significant diseases due to its high morbidity and mortality, despite the availability of various treatment methods that are being continuously improved. It is more common in older populations, and with the aging of the population it has become a growing global issue. On the other hand, many diseases, especially heart diseases, can manifest as heart failure (HF).

Although those of us who work in the field might feel that the issues surrounding HF are well-known, we can still be surprised by (new) data. Over the last few months, we have witnessed the rise of the COVID-19 (COVID) virus pandemic, that has changed all of our lives and affected many people, in many cases with a lethal outcome. COVID infection primarily affects the respiratory system, but once it has spread it can influence the whole organism via different mechanisms, and HF can also be one of its manifestations, especially in the terminal phase. It should be noted that as many as 80% of patients can have mild or no symptoms while still transmitting the disease. The COVID pandemic has made us face new challenges and taught us or warned us of current problems or of issues that will arise in the near future with regard to both new and previously known infections and diseases.

The working groups of the European Society of Cardiology and Heart Failure Association are continuously developing and implementing numerous activities in addition to providing guidelines and organizing congresses, trainings, and meetings, with the ultimate goal of improving the prognosis of patients with heart failure, and the Croatian Cardiac Society is part of this process. Notably, this participation includes the Heart Failure III Registry, the ATLAS project (with epidemiological data from individual countries), the Heart Failure Awareness Week (this year from May 4 to May 10), and an initiative for general practitioner patient care for patients with HF with the help of specialized medical nurses, and telemedicine support (which was especially useful during the pandemic). In the rest of this article, we will provide a review of the treatment of acute and chronic HF during the COVID-19 pandemic.

Guidelines of the European Society of Cardiology for the diagnosis and treatment of cardiovascular diseases during the COVID-19 pandemic in relation to heart failure

Patients with comorbidities are infected by COVID more often with a higher disease severity and mortality, especially if the comorbidity involves cardiovascular (CV), respiratory, renal, or malignant diseases, diabetes, and arterial hypertension (1). One study (n=8910) followed patients with COVID based on comorbidities. The mortality was 5.8%, and the risk was especially pronounced in the older age group (>65, 10%: 5.8%), in coronary artery disease (CAD, 10.2%: 5.2%), heart failure (15.3%: 5.6%), chronic obstructive pulmonary disease (COPD, 14,2%: 5,6%), arrhythmia (11.5%: 5.6%), and smoking (9.4%: 5.6%). CV diseases significantly increased mortality (2). In a meta-analysis of 6 studies, hypertension and CV diseases were present in 17.1% of those hospitalized for COVID, with up to 3 times higher risk of higher disease severity (3).

COVID affecting the heart usually manifests as cardiac damage and heart failure, arrhythmia, and cardiac arrest. Different signs of infection can be prevalent in patients with COVID (high fever, muscle and joint pain, sore throat, headache, fatigue, skin changes, smell and taste disorders, and disorders of the digestive and urinary systems), and breathing problems accompanied by chest pain are common, which can resemble myocardial infarction. All known clinical methods must be used to establish a diagnosis. If performed, coronarography is usually normal. In a study on patients with COVID from China (1/2020; 552 hospitals, n=1099, average incubation – 4 dana, febrility 43%, lymphocytopenia 83.2%, typical changes observed on lung CT 56%), the severe form of the disease was observed in 6.1% of patients (5% were admitted to intensive care, 2.3% were placed on a respirator, and 1.4% died) (4). A fifth of the infected had signs of myocardial damage, in which case the mortality rate was several times higher. In the deceased, the heart was affected in about 40% of cases, 12% did not have prior CV diseases, whereas 25-50% of patients with pneumonia had comorbidities.

Patients with COVID-19 infection can develop a new CV disease or present with progression of an existing disease (CAD, cardiomyopathies, various form of HF). Heart failure can be the consequence of acute viral myocarditis and a “cytokine storm”, but also the result of exacerbation of chronic HF. The high cardiometabolic burden during infection causes overwork of the heart, while cytokines can exacerbate shock and circulation changes, including the coronary vessels and microthrombosis. Respiratory infections accompanied by hypoxia lead to a higher incidence of mortal outcomes. Approximately one third of patients with the severe form of the infection can develop HF.