Sudden Cardiac Death in COVID-19 Patients – A New Potential Risk
According to a study published in BMJ, Researchers have found that cardiac arrest is common in critically ill COVID-19 patients. The risk increases even if CPR is provided – especially in patients aged 80 and above. The same study found that patients who had in-hospital cardiac arrest were older (average age 65 – 70 years) with underlying comorbidities.
COVID-19 and sudden cardiac death: A new potential Risk
Sudden cardiac death (SCD) has emerged as one of the disturbing concerns with COVID-19 infection. COVID-19 has also been associated with higher risk of out-of-hospital cardiac arrest (OHCA) as well.
Heart Rhythm Society carried out a global survey. According to this survey Atrial fibrillation was the most commonly reported tachyarrhythmia (25%) followed by bradycardia (10%) and then complete heart blockage. All these evidences point out some sort of association with COVID-19 infection, SCD and increase in mortality rate.
Arrhythmias and Sudden Cardiac Death
According to a study published in Indian Heart Journal, among the 10 t0 15% of patients hospitalized for severe COVID-19, life threatening arrhythmias have been reported with elevated troponin levels indicating myocardial injury. Therefore, patients with more severe systemic illness in the ICU setting have invariably reported arrhythmias and sudden cardiac death.
There could have been multiple factors involved in such cases – including hypoxia, drug interactions, dyselectrolytemia, acidosis, acute coronary syndrome and myocarditis, and stress cardiomyopathy.
In an observation study which has been recently carried out in recovered patients with a mean duration of 71 days from infection, 78% recovered patients were found to have some cardiac involvement and 60% had ongoing inflammation with pericardial enhancement and regional scar tissue. In another retrospective study 58% patients reported cardiac symptoms with myocardial edema; 54% had gadolinium enhancement and 31% showed perimyocarditis and scarring. This has been seen as the potential cause of sudden cardiac death in some patients after recovery from COVID-19.
A combination of drugs used to treat severe infections – such as azithromycin and ritonavir or lopinavir when used alone or in combination with other drugs have also been implicated to confer a high risk of sudden cardiac death (SCD).
Undiagnosed heart disease can cause Acute Coronary Syndrome
In severe viral infections like COVID-19 acute inflammatory response, increased metabolic demand, reduced cardiac reserve and pre-existing chronic cardiovascular disease can become unstable. And also due to acute infection, the inflammatory activity within atherosclerotic plaques is aggravated – making plaques susceptible to rupture – owing to which they rupture and cause acute coronary syndrome – resulting in SCD.
The Reasons for Fatal Arrhythmias in COVID-19
The direct virus involvement with the lungs may cause hypoxia – which is severe. In addition, severe systemic inflammatory state, cardiac dysfunction, drug side effects, intravascular volume imbalances, electrolyte derangements may also result in fatal arrhythmias.
COVID-19 infections increase the risk of both arterial and venous thrombosis. Acute inflammatory state and immobilization of patients in ICU can contribute further to thrombosis. Coronary thrombosis with myocardial infarction or pulmonary thrombosis (acute thrombosis) can manifest into SCD. In almost 50% of the patients admitted to ICU pneumonia develop thrombotic events. Pulmonary thromboembolism is the most common thrombotic complication. It has been seen in almost one-third of all critically ill patients. Acute pulmonary embolism is a perpetuator of SCD.