DISCUSSION
Patients with advanced cardiac disease are at high risk of arrhythmic events that may impact prognosis, such as AF, VT and VF. In this study we have shown that during the 56 days long lockdown due to COVID-19 epidemics, the incidence of both atrial and ventricular arrhythmias was significantly increased in subjects with AICD and ICD/CRT. These data were available through remote device monitoring and raise some interesting issues regarding both cardiac pathophysiology and patients’ clinical management.
In order to contrast the spread of the new COVID-19 epidemic, at the beginning of March 2020 the Italian Government decided for more restrictive containment measures: a sudden and radical change has occurred in the habits and lifestyles of the population, with a drastic reduction of any form of personal contacts and socialisation with relevant social ed economic consequences. These preventive measures did limit the spread of this contagious disease in southern Italy. The effects of lockdown period were explored in different contexts and terms: eating habits and lifestyle changes,10approaches implemented to support teleconsultations and management of AF and heart failure patients.11,12 new-onset of arrhythmic events such as atrial fibrillation,3 impact on interventional electrophysiology units routine and emergency work,13 .
It is well established that patients affected by COVID-19 infection may develop cardiac complications, also in terms of both atrial and ventricular arrhythmias. Such complications are more frequent in severely ill subjects and may represent a negative prognostic factor in terms of morbidity and mortality14 This created major concern for the patients with chronic heart disease. However even in cardiopathic subjects who were not affected by COVID-19 related pneumonia, restrictive measures created distress and cardiac complications.
In our study we investigated the effects of lockdown period in in a cohort of stable patients followed up through AICD and CRT-D remote monitoring in terms of incidence rate of cardiac arrhythmias, by comparing these data with data from the same period in 2019. Study population has shown an increase in the incidence of arrhythmias: during lockdown period VT/VF occurred in 4.8% and new-onset AF in 8.2% of study patients, while the same arrhythmias were respectively observed in 2.3% and 5.2% of subjects during the corresponding 2019 period. These results were strengthened in terms of number of arrhythmic events: VT, VF and AF episodes were recorded during the lockdown time interval much more frequently than the correspondent reference period.
Our study method, based on diagnosis obtained through continuous remote monitoring, has allowed to eliminate the “issue” of potential and dangerous underdiagnosis associated with the routine discontinuous in-office clinical assessment; this issue has become more relevant during the recent COVID-19 pandemic outbreak because of the widely reported patients’ tendency to avoid hospitalization during the epidemic peak phase (Russo, Danish e qualcos’altro) and to the reduction of hospitals’ accessibility. In fact the data of the Danish Registry have shown a 47% drop in registered diagnosed new-onset AF cases, revealing a potential and “dangerous” risk of undiagnosed AF with potential detrimental prognostic effects3 . This tendency, that could possible cause underdiagnosis and underreporting, was bypassed in our investigation by continuous remote monitoring that allowed us to quantify the real arrhythmic burden associated to lockdown in terms of higher incidence of relevant arrhythmias.
To the best of our knowledge, this is the first study to report on the incidence of cardiac arrhythmias related to the COVID-19 outbreak in AICD patients on such a large sample size. Our results are in agreement with the recently published data of a multi-center study performed in our region, that show a significant increase in the number of hospitalizations through the emergency department due to clinically relevant arrhythmias during the lockdown time interval, despite the reduced number of scheduled hospital admissions and rhythm management procedures4.
The increased incidence of dysrhythmias during lockdown may be related to “high-stress conditions” that have characterized lockdown period. As the strict lockdown measures were associated to change in daily habits, social discomfort, economic recession and jobs lay-offs, it is not surprising that in the Italian general population high rates of negative mental health outcomes and different COVID-19 related risk factors were reported15 . Several studies, both in animal models and humans, suggest that emotions and mental stress play a significant role in the onset of arrhythmias and the occurrence of sudden death due to “the heart-brain interaction”.16-18 Emotions and mental stress can influence heart rhythm in several ways, including impaired sympathetic/parasympathetic balance, alterations in the spatial distribution of autonomic input to the heart, or by causing coronary arterial vasoconstriction and ischemia. Anger has been shown to be the commonest emotion prior to the onset of ventricular arrhythmia also in patients with ICD.16,18 Mental stress and anger predispose to atrial arrhythmias particularly in younger patients with ‘lone’ AF; furthermore stress increases both the frequency of cardiac rhythm disturbances and the lethality of ventricular arrhythmias17,18 . Specific regions in the brain may be responsible for mediating the pro-arrhythmic effects of emotions.18 This functional connection between the brain and the heart may be the cause of the increased incidence of arrhythmias in our study population that have experienced lockdown-related stressful life. It is conceivable that this phenomenon, assessed for the general population,18 may be even more pronounced in a population with advanced cardiac disease and might play a causative role of new-onset arrhythmias. In this context, a potential role of disorders of metabolic and hormonal homeostasis caused by mental and psychological stress was not investigated and it cannot be ruled out.
As a change in the incidence of neither atrial nor ventricular arrhythmias was recorded in the year preceding lockdown, it is unlikely that our findings are due to cardiac disease progression.
Our experience confirmed how the use of remote monitoring, recognized as “the new standard of care” for patients with cardiac implantable electronic devices by HRS Expert Consensus Statement5plays an even more crucial role during the current pandemic as clinical follow-up during a period of social distancing and limited access to health facilities represent a difficult challenge for subjects who require regular and/or continuous surveillance.19