Newswise — Barcelona, Spain – 18 April 2023

Research presented at the 2023 EHRA scientific congress of the European Society of Cardiology (ESC) indicates that individuals with severe COVID-19 requiring mechanical ventilation have a 16-fold higher likelihood of developing ventricular tachycardia within six months compared to those who did not experience severe infection. Additionally, the study found that the risks of other heart rhythm disorders were also increased.

Dr. Marcus Stahlberg of the Karolinska Institute in Stockholm, Sweden, who conducted the study, noted that while the likelihood of developing ventricular tachycardia or other arrhythmias after severe COVID-19 is still low for an individual patient, it is significantly higher than in those who did not experience severe infection.

The main goal of this study was to examine the risk of arrhythmias in the long term after being discharged from an intensive care unit (ICU) for COVID-19 and requiring mechanical ventilation. To achieve this objective, the researchers utilized the Swedish ICU register to identify all COVID-19 patients who were treated with mechanical ventilation and were discharged alive from an ICU between March 2020 and June 2021. The researchers then matched each patient with up to 10 individuals from the general population who shared the same age, sex, and district of residence. To record any new diagnoses of arrhythmias after discharge from the ICU, the researchers used multiple mandatory national registries.

The main outcome that the researchers were interested in was hospitalization due to various heart rhythm disturbances, including ventricular tachycardia, atrial fibrillation, other tachyarrhythmias, or bradycardia/pacemaker implantation. Ventricular tachycardia is a serious and potentially life-threatening heart rhythm disorder where the ventricles beat too quickly, causing inadequate blood supply to the body. Atrial fibrillation is an irregular and rapid heartbeat that can lead to shortness of breath and increase the risk of stroke. "Other tachyarrhythmias" refers to a rapid heartbeat that is not caused by atrial fibrillation. "Bradycardia or pacemaker implantation" is a combined outcome that includes slow heart rate or the need for a pacemaker due to a slow heart rate.

The researchers conducted an analysis to determine the likelihood of developing each type of arrhythmia in individuals with severe COVID-19 compared to those without severe infection. To ensure accurate results, the analyses were adjusted for various factors known to be associated with the development of heart rhythm disorders, such as age, sex, high blood pressure, diabetes, high blood lipids, chronic kidney disease, and socioeconomic status (including education level, marital status, and income).

The study involved a total of 3,023 patients who had severe COVID-19 and required mechanical ventilation at an ICU in Sweden, and a control group of 28,463 individuals from the general population who had not been in an ICU with COVID-19 requiring mechanical ventilation. The average age of participants was 62 years, and 30% were women. As noted by Dr. Stahlberg, older age and male sex are two significant risk factors for developing severe COVID-19, and these factors were reflected in the study participants.

The average follow-up period for the study was nine months. Among patients who had severe COVID-19 and required mechanical ventilation, the incidence rates of ventricular tachycardia, atrial fibrillation, other tachyarrhythmias, and bradycardia/pacemaker implantation were 15.4, 78.4, 99.3, and 8.5 per 1,000 person-years, respectively. In comparison, the incidence rates of the same conditions in the control group were much lower at 0.9, 6.0, 6.7, and 0.9 per 1,000 person-years, respectively.

The study found that patients who had severe COVID-19 requiring mechanical ventilation had a significantly higher risk of developing heart rhythm disorders compared to the control group. Specifically, they had a 16-fold higher risk of developing ventricular tachycardia, a 13-fold higher risk of developing atrial fibrillation, a 14-fold higher risk of developing other tachyarrhythmias, and a 9-fold higher risk of requiring bradycardia/pacemaker implantation, as compared to individuals in the control group.

Dr. Stahlberg emphasized the importance of monitoring for heart rhythm disorders in COVID-19 patients who required mechanical ventilation, as they may already have underlying health conditions. He advised that patients who experience palpitations or irregular heartbeats after hospital discharge should seek medical attention promptly to be evaluated for possible arrhythmias. Early detection and treatment of heart rhythm disorders can help prevent further health complications and improve outcomes.

Dr. Stahlberg concluded that previous studies have also reported an increased risk of heart rhythm disorders in COVID-19 patients who did not require ICU treatment, which, combined with their new findings, suggests that hospital systems should prepare for a potential increase in patients requiring management for new onset arrhythmias. With over 650 million reported COVID-19 cases globally, healthcare providers should remain vigilant and ready to provide appropriate care to patients with potential heart rhythm disorders following COVID-19 infection.