Letter to the Editor Regarding: Acute Coronary Syndrome in the COVID-19 Pandemic: Reduced Cases and Increased Ischaemic Time by Sutherland et al. Heart Lung Circ. 2022;31(1):69-76.

Sutherland and colleagues recently reported a reduction in patients admitted with acute coronary syndrome (ACS) and an increase in total ischaemic time during the first and second wave of the COVID-19 outbreak in Melbourne [[1]Sutherland N. Dayawansa N.H. Filipopoulos B. Vasanthakumar S. Narayan O. Ponnuthurai F.A. et al.Acute coronary syndrome in the COVID-19 pandemic: reduced cases and increased ischaemic time.Heart Lung Circ. 2022; 31: 69-76https://doi.org/10.1016/j.hlc.2021.07.023Abstract Full Text Full Text PDF PubMed Scopus (2) Google Scholar]. They also observed a 20% rebound increase in ACS presentations following the relaxation of public health restrictions in November–December 2020 compared to the same period of 2019 and suggested that this could represent long-term sequelae of untreated ACS including reinfarction and heart failure. However, several additional mechanisms could play a role. A trend of reduced hospitalisations for all ACS types during the pandemic has been observed worldwide [1Sutherland N. Dayawansa N.H. Filipopoulos B. Vasanthakumar S. Narayan O. Ponnuthurai F.A. et al.Acute coronary syndrome in the COVID-19 pandemic: reduced cases and increased ischaemic time.Heart Lung Circ. 2022; 31: 69-76https://doi.org/10.1016/j.hlc.2021.07.023Abstract Full Text Full Text PDF PubMed Scopus (2) Google Scholar, 2Fardman A. Oren D. Berkovitch A. Segev A. Levy Y. Beigel R. et al.Post Covid-19 acute myocardial infarction rebound.Can J Cardiol. 2020; 36: 1832.e15-1832.e16Abstract Full Text Full Text PDF Scopus (10) Google Scholar, 3Rattka M. Dreyhaupt J. Winsauer C. Stuhler L. Baumhardt M. Thiessen K. et al.Effect of the COVID-19 pandemic on mortality of patients with STEMI: a systematic review and meta-analysis.Heart. 2021; https://doi.org/10.1136/heartjnl-2020-318360Crossref Scopus (25) Google Scholar]. Besides social distancing, stay-at-home orders, and fear of acquiring the infection, attenuated exposure to well-recognised ACS triggers, particularly reduced air pollution, and decreased physical and work activities, has been linked to this phenomenon [[3]Rattka M. Dreyhaupt J. Winsauer C. Stuhler L. Baumhardt M. Thiessen K. et al.Effect of the COVID-19 pandemic on mortality of patients with STEMI: a systematic review and meta-analysis.Heart. 2021; https://doi.org/10.1136/heartjnl-2020-318360Crossref Scopus (25) Google Scholar,[4]Čulić V. AlTurki A. Proietti R. Covid-19 pandemic and possible rebound phenomenon in incidence of acute myocardial infarction.Can J Cardiol. 2021; 37: 1294Abstract Full Text Full Text PDF PubMed Scopus (2) Google Scholar]. The alleviation of restrictions after the pandemic waves restored the level of exposure to ACS triggers which could have contributed to a gradual increase in ACS hospitalisations [[4]Čulić V. AlTurki A. Proietti R. Covid-19 pandemic and possible rebound phenomenon in incidence of acute myocardial infarction.Can J Cardiol. 2021; 37: 1294Abstract Full Text Full Text PDF PubMed Scopus (2) Google Scholar]. Moreover, fear of lack of medical care, lockdown stress, anger, loneliness, job loss, financial stress, and binge smoking have been suggested as ACS triggers due to the ramification of the pandemic [[5]Hammoudeh A. Abu-Hantash H. Tabbalat R. Al-Mousa E. Madanat E. Al-Muhaisen R. et al.The Covid-19 pandemic and triggered acute myocardial infarction among non-infected individuals.Int J Clin Cardiol. 2020; 7: 185Google Scholar]. Along this line, a post-restriction increase in hospitalisations for ST-segment elevation myocardial infarction has been documented in Israel [[2]Fardman A. Oren D. Berkovitch A. Segev A. Levy Y. Beigel R. et al.Post Covid-19 acute myocardial infarction rebound.Can J Cardiol. 2020; 36: 1832.e15-1832.e16Abstract Full Text Full Text PDF Scopus (10) Google Scholar]. Anti-pandemic measures favour sedentary behaviour, physical inactivity, unhealthy nutritional habits, weight gain, and increased alcohol consumption, as confirmed by recent meta-analyses [[6]Bakaloudi D.R. Barazzoni R. Bischoff S.C. Breda J. Wickramasinghe K. Chourdakis M. Impact of the first COVID-19 lockdown on body weight: a combined systematic review and a meta-analysis.Clin Nutr. 2021; https://doi.org/10.1016/j.clnu.2021.04.015Abstract Full Text Full Text PDF Scopus (21) Google Scholar,[7]Bakaloudi D.R. Jeyakumar D.T. Jayawardena R. Chourdakis M. The impact of COVID-19 lockdown on snacking habits, fast-food and alcohol consumption: a systematic review of the evidence.Clin Nutr. 2021; https://doi.org/10.1016/j.clnu.2021.04.020Abstract Full Text Full Text PDF Scopus (20) Google Scholar]. Consequent negative effects on metabolism likely worsened the population’s cardiovascular health and, given their presence for over a year now, could have increased the number of vulnerable coronary patients [[4]Čulić V. AlTurki A. Proietti R. Covid-19 pandemic and possible rebound phenomenon in incidence of acute myocardial infarction.Can J Cardiol. 2021; 37: 1294Abstract Full Text Full Text PDF PubMed Scopus (2) Google Scholar]. Accordingly, increased population cardiovascular vulnerability coupled with enhanced exposure to ACS triggers could be important mechanisms of a rebound increase in ACS. Letter to the Editor: Acute Coronary Syndrome Trends and COVID-19 Waves (Response to the Letter of Čulić et al.)Heart, Lung and CirculationVol. 31Issue 3PreviewWe would like to thank Professor Čulić and colleagues for their interest in our paper [1] and for their comments [2]. We agree that multiple factors contributed to both a reduction in acute coronary syndrome (ACS) presentations during the first and second waves of the COVID-19 pandemic in Melbourne, as well as for the rebound in presentations when restrictions were eased. Full-Text PDF