After 3 long years of the Corona virus disease 2019 (COVID-19) pandemic, several thoughts come to our minds: We have survived and even successfully managed the pandemic in our country. But:

  • Did we really do a good job?

  • What has the virus taught us?

  • What do we know now, and what can be improved?

These questions and considerations still occupy public opinion [1] and are also the subject of this editorial.

Therefore, let us first address some general aspects of the pandemic, which has now become an endemic, but is not over yet.

Which lessons should our health system take note of, and what should be changed? Here are some episodes and their catchphrases:

The basics were personal hygiene and masks: This type of protection has been known for centuries. But at the beginning of the pandemic, masks and other PPE (personal protective equipment) were not available in the necessary amount. They had to be imported from China or other countries.

Indirect evidence only: We followed the obligatory regulation to wear surgical or FFP2 masks in public transportation or in stores. We obeyed social distancing rules. But we never evaluated their effectivity under daily circumstances. Instead, the findings of numerous experiments were published on droplet size and their dispersion. The only practical information we received was that fewer infections with the common cold or influenza occurred during the pandemic when compared with the pre-pandemic years.

Alternative facts: Every morning, news bulletins informed us about the daily infection rate. And we believed it. In reality, even today we still do not know exactly how many individuals have been infected with COVID-19 in Germany, or when they were infected and where. Many figures were just extrapolations.

A safety illusion: We finally got a “perfect” corona warning app. It came very late and it was claimed that it offered privacy protection and data security. But in fact, it was anonymized too widely. For people in larger cities, who had many contacts in public, it was impossible to find out which of them were critical. Protection of privacy is important, but this warning app overstretched it. When going out for dinner, people preferred the unofficial, simpler luca app.

Just a personal impression: In November 2021 all of the top officials of the local public health department of my hometown were on vacation. At that time almost everyone wanted to receive another vaccination or booster dose. A group of retired physicians were ready to organize a vaccination campaign in cooperation with the biggest department store in town—best to get vaccinated when visiting the store or having a cup of coffee. Official help from the local health authority was unavailable. Nevertheless, we started the campaign with the help of a single general practitioner and a local pharmacist. Eventually, 1111 individuals were vaccinated and all documents were channeled into the central registry of the Robert Koch Institute. This may be a petitesse, but it was a bureaucratic steeplechase in our public health system. It was overcome by private initiative.

Futile testing: Pupils were required to be tested for COVID-19, but we never received hard data on the effectivity of this measure! Instead, schools also underwent complete lockdowns.

Blind flight without data: In countries like Israel or the Scandinavian countries, a functioning electronic patient document was available. Our local health authorities reported infected patients via old-fashioned fax machines, whereas our private communications worked online via email, WhatsApp, or Signal messengers and Zoom conferences. In Israel, physicians knew on time which patients had a high-risk status through infection. They could be warned on time and they were prioritized for vaccinations because, in their country, an electronic patient record was in use.

Uncertainty about intensive care beds: At the beginning of the pandemic, we did not know how many beds in intensive care units were available, until the DIVI (Deutsche Interdisziplinäre Gesellschaft für Intensiv- und Notfallmedizin) reactivated their old registry.

Looking at empty shelves: We remember the rush for toilet paper in stores and the empty shelves found there. Too little prevention, even for the simple must-haves of daily life, and too much hurry by people to collect only for themselves.

Unavailable drugs: For the symptomatic treatment of headache, myalgia or fever in children, drugs became scarce because they were no longer produced in Germany, which had claimed to be the pharmacy of the world in the 20th century.

What were the positive aspects? The solidarity between neighbors was impressive. I still remember the daily corona singing sessions in our street in early 2020, with all of us keeping a distance of 3 m. We were not only neighbors then, but became friends.

Who were the proactive in the medical community? The general practitioners, the physicians in hospitals, and the healthcare workers did a great job. Although they were publicly applauded, many are still waiting on a bonus or an increase in salary. General practitioners were not well informed and poorly supported in the early phase of the pandemic. Although pandemic plans were in existence, they did not consider the ambulatory component of patient care adequately. They had to improvise and acted independently. And it worked.

Antiviral treatment was promising but also somewhat disappointing. The effects of remdesivir were limited to the early phase of viremia. Paxlovid is of benefit in severe cases only. Nevertheless, sufficient data on their use still have to be collected.

What were the game-changers? The decisive breakthrough was immunization with vaccines, particularly the RNA vaccines from BioNTech and Moderna. They made the difference. It was not the politicians in daily talk shows but the scientific excellence and passion of a few individuals. They did it!

The heart received increasing attention. At the beginning of the pandemic, the respiratory tract, lung infection and inflammation, and their intensive care treatment received the most attention. For the surviving patients or those after infection from less severe mutations, cardiac sequelae and side effects as well as long COVID became a matter of increasing interest [2].

The authors of this special issue of HERZ/Cardiovascular Diseases reviewed the last 3 years of the SARS-CoV‑2 pandemic in their own specialty. We have asked them the same questions as in 2020 [3]: What do we know and what do we need to know after 3 years?

Chen Intensive, Hu We, and Dao Wen Wang from Wuhan were the first to report on the pandemic in early 2020 in HERZ [4]. They reviewed data from their hospital and looked at China as a whole. This time they present their views of the pandemic from the time and the point of origin to the official end of the pandemic in China. They sum up: “Because SARS-CoV‑2 can bind to the angiotensin 2 receptor on the surface of cardiomyocytes, it may also lead to cardiac injury. COVID-19-associated cardiac injury is not rare in clinical practice, and most of it is modest, while a few cases might progress to fulminant myocarditis.”

Junbo Ge from Shanghai reflects on the Chinese way of coping with the pandemic: China has effectively brought the pandemic under control and reached a state of “dynamic zero” cases. A dynamic zero-COVID policy is not identical to a zero-COVID policy, which seeks to completely eliminate the virus. This is virtually impossible. According to Chinese statistics, the number of hospitalized COVID-19 patients reached a peak of 1.625 million on January 5, 2023, and since then declined to 26,000 by February 13. This corresponds to a reduction of 98.4% from the peak. His contribution after 3 years focusses on intensive care issues [5].

Bernd Kowall and Andreas Stang report on excess mortality in the course of the pandemic, which is an important indicator of health consequences. Unlike the evaluation of causes in death statistics, the calculation of excess mortality does not depend on the attribution of causes of death and the quality of the death certificates. It throws light on a problem of statistics on pandemics in general with special insights into the COVID-19 pandemic. Their additional viewpoint “On the gap between objective and perceived risks of COVID-19” throws light on “German angst” and the problem of heuristics in media and in our perception. The contribution in 2020 elaborated on early trends in COVID-19 statistics [6].

Anselm Gitt collected data from one of the very few COVID-19 registries in Germany [7]. He shows that the waves of the pandemic were initially paralleled by the occupation of intensive care beds. During the Omicron wave, there were fewer severe cases despite its increased infectivity.

Bernhard Maisch already focused on cardiac inflammation in the pandemic in 2020 [8]. Now it has become clear that the virus can infect the heart through angiotensin-converting enzyme 2 (ACE2) and IMPRSS receptors. But the virus is rarely found in myocytes, more often in interstitial and endothelial cells and in monocytes. Myocardial lesions occur through vasculitis, small thrombotic events, and by cytokines. The attractive idea of a cytokine storm is less common than initially anticipated. Long COVID and post-COVID syndromes have become a mixed bag of different causes, whereby autoimmune processes in various organs are likely to play a contributory role. Myocarditis and pericarditis can also be found after the second vaccination, particularly in young men. The long-term burden on the individual remains unknown. Guidelines such as the European Society of Cardiology (ESC) Guideline were intended as learning guidance for the medical community [9,10,11].

Karl-Heinz Kuck already reviewed the influence of the pandemic on arrhythmias and sudden cardiac death in 2020 [12] and he also does so in the current issue. Both the pandemic and the vaccination altered heart rate variability and interacted with the risk of arrhythmias and sudden cardiac death. Infection by COVID-19 induced more rhythm disturbances, including serious and lethal disturbances.

Alexander Dutsch and Heribert Schunkert observed that, contrary to initial views that the use of ACE inhibitors/angiotensin receptor blockers (ARBs) may increase the risk for a deleterious disease course, these agents, such as telmisartan, may actually be beneficial or remain neutral in patients affected by COVID-19. A small trial with metoprolol also reported a benefit on treatment. The authors deliberated on this aspect back in 2020 [13].

Rolf Dörr assesses the patients and their problems during the pandemic from the viewpoint of his cardiology practice [14]. His summary can be shared by medical generalists too: Vaccination was the most effective protective measure against COVID-19. His perspective is that countries should continue to work toward vaccinating at least 70% of their population, prioritizing the vaccination of 100% of healthcare workers and 100% of the most vulnerable groups. This includes people over 60 years of age and immunocompromised patients.

Rainer Moosdorf covers two main problems faced by cardiac surgeons during the pandemic: Acute respiratory distress made extracorporeal oxygenation necessary in a variable number of patients, who had to be treated in postanesthesia care units and even more so in cardiac surgical intensive care units. This organizational measure left only a limited number of beds in the intensive care units available for elective surgery cases. In addition, heart surgical interventions during the pandemic were associated with an increased risk-adjusted mortality [15] and significantly higher hospital costs.

Holger Thiele covered the spectrum of cardiac emergencies in 2020 [16, 17]. Together with Uwe Zeymer he now looks behind the decreasing rates of acute coronary syndrome (ACS) and the reduction in cardiovascular mortality and morbidity during the pandemic. Reduced hospitalization rates of patients with ACS, ST-segment elevation myocardial infarction (STEMI), or arrhythmias were observed worldwide. It remains unclear whether this reduction occurred due to a true decrease in coronary disease, or less stress in the home office, or reduced social contacts, or less air pollution because of decreased car and air traffic.

Juliane Heitmann, Julian Kreutz, Sümeya Aldudak, Elisabeth Schieffer, Bernhard Schieffer, and Ann-Christin Schäfer present the case of a 38-year-old female patient with complex symptoms such as exercise-induced dyspnea, palpitations, thoracic burning, blood pressure dysregulations, Raynaud’s syndrome, muscle pain, and post-exertional malaise in temporal relation after vaccination against SARS-CoV‑2 and a twofold infection. She was successfully treated in the Long COVID Outpatient Clinic through H.E.L.P. apheresis.

Julian Kreutz, Juliane Heitmann, Ann-Christin Schäfer, Sümeya Aldudak, Bernhard Schieffer, and Elisabeth Schieffer point to a link between the transmission of SARS-CoV‑2 and the severity of the disease with various environmental factors. Air pollution with fine particulate matter is thought to play a crucial role. Both climatic and geographic aspects must be taken into account.

More than chronic fatigue? This is the topic of Ulf Seifart’s contribution on long COVID syndrome. Its incidence is estimated to be about 15% of all symptomatically infected patients. The etiology of long COVID is not fully understood. The following pathogenetic processes are discussed: an endothelial dysfunction with microcirculatory disturbances and subsequent organ damage, a residual virus or virus particles, and/or an excessive autoimmune process.

Altogether, this issue of HERZ covers many aspects relevant to the cardiologist and internist during the pandemic. We know more about the virus as well as about the mechanisms, causes, and consequences in different settings. Most of all, we are fortunate to have experienced that the breakthrough in prevention by vaccination has “changed the game” and that numerous members of the medical profession have successfully tried their best to save lives or mitigate the different manifestations of SARS-CoV‑2. The end of the pandemic is just the beginning of the endemic phase of the viral disease, which remains difficult to treat. The editors and authors of this issue of HERZ hope that we have learned a lot. But there is still much to do to prevent the next endemic or pandemic that is likely to come.

Yours,

Prof. Dr. med. Bernhard Maisch

Dr. med. Rolf Dörr