The effect of the COVID-19 pandemic on acute coronary syndrome hospitalizations and out-of-hospital cardiac arrest in Greece.

OBJECTIVES: After coronavirus disease 2019 (COVID-19) outbreak, striking decreases in the number of hospital admissions for acute coronary syndromes (ACSs) and rises in rates of out-of-hospital cardiac arrest (OHCA) have been noted. STUDY
DESIGN: This is an analysis of prospectively collected data from a cardiology department in a single, large volume hospital of the National Health System of the Metropolitan area of Athens.
METHODS: We investigated the numbers of OHCA and hospital admissions for ACS during a 1-year period and made comparisons between the pre-COVID-19 and the COVID-19 outbreak periods.
RESULTS: One hundred and eighty five patients were admitted during the total period of observation with the diagnosis of ACS. The mean monthly number of admissions for ACS for the pre-COVID-19 era was significantly higher than that for the post-COVID-19 era (20.1 ± 7.8 vs 8.8 ± 6.5 admissions, Ρ = 0.024). The cases of OHCA which were transferred to our emergency room department by emergency medical services during the same period were nominally lower in the prepandemic compared with the postpandemic era (1.9 ± 1.7 vs 4.0 ± 4.6, P = 0.28).
CONCLUSIONS: The present study provides hints on the potential unintended consequences of the pandemic in countries characterized by fewer COVID-19 cases and fatalities but prompt measures of social contact restrictions and lockdown.

To face the coronavirus disease 2019 (COVID-19) pandemic, strict social containment measures have been implemented worldwide, and healthcare systems have been reorganized to cope with the expected surge in the numbers of critically ill patients. However, Greek authorities adopted strict and timely social distancing policies to contain COVID-19 spread. These policies were proven highly efficient as Greece reported one of the lowest incidence and fatality rates worldwide during the first pandemic wave. After COVID-19 outbreak, striking decreases in the number of hospital admissions for acute coronary syndromes (ACSs) have been noted. , Similarly, early studies from regions severely affected by the pandemic have supported that the rates of out-of-hospital cardiac arrest (OHCA) have significantly risen during this period. Furthermore, mechanical complications of ACS, which have been rendered infrequent in the era of timely coronary reperfusion, have resurfaced during the pandemic. Lockdown measures which hinder access to healthcare services and/or fear of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) contraction, which deters patients from seeking health care, could be advocated as potential explanations for aforementioned trends. Nonetheless, data from countries, which have been least affected by the pandemic, such as Greece, are for the time limited. The aim of the present analysis was to investigate the numbers of (a) hospital admissions for ACS and (b) OHCA during a 1-year period (July 1, 2019–June 30, 2020) and make comparisons between the pre-COVID-19 and the COVID-19 outbreak periods.

This is an analysis of prospectively collected data from a cardiology department in a single, large volume hospital of the National Health System of the Metropolitan area of Athens (Laiko General Hospital, Athens). Based on an ad hoc design form, we collected demographic data, data pertaining to patient history, clinical presentation, laboratory profile, treatment, and in-hospital outcomes of patients presenting with ACS. We divided the study period into two subperiods: 1st July 2019 up to 31st January 2020 (prepandemic period) and 1st February up to 30th June 2020 (COVID-19 outbreak period). To assess for simultaneous trends in OHCA, we analyzed all cases of OHCA which were transferred to our emergency department during the same period by emergency medical services (EMSs). We collected demographic data (such as age and gender) and data pertaining to patient history among the latter patients. The study was approved by the ethics committee of our institution and was carried out in accordance with the Declaration of Helsinki.

One hundred and eighty five patients were admitted during the total period of observation with the diagnosis of ACS. The mean monthly number of admissions for ACS for the pre-COVID-19 era was significantly higher than that for the post-COVID-19 era (20.1 ± 7.8 vs 8.8 ± 6.5 admissions, Ρ = 0.024, Supplementary Fig. 1A). The number of hospitalizations for ACS was remarkably lower for the months that aggressive lockdown measures (quarantine) were enforced (March and April 2020) when compared with the other months of the pandemic (5.5 ± 2.1 vs 11.8 ± 6.8, P = 0.16).

Τhe baseline characteristics of the patients hospitalized for ACS during the study period and the characteristics of their hospitalizations stratified by the two subperiods are depicted in Table 1 . There were not significant differences in terms of age, history, and other available parameters indicating severity (type of ACS, high-sensitivity troponin T levels, left ventricular ejection fraction). Patients presenting before the COVID-19 era had significantly lower levels of total cholesterol (168 ± 43 vs 185 ± 48 mg/dl, P = 0.036) and a trend toward lower levels of low-density lipoprotein (LDL) cholesterol (99 ± 37 vs 111 ± 37 pg/ml, P = 0.067), compared with patients presenting during the pandemic. These differences are most probably attributed to the higher rates of statin receipt among patients of the pre-COVID-19 era (45.4% vs 22.7%, P = 0.007). Importantly, patient outcome rates in terms of invasive therapy and death did not differ between the two subperiods (Table 1). Interestingly though, the patients presenting before the COVID-19 era had significantly more diseased vessels compared with patients of the COVID-19 era (1.9 ± 1.0 vs 1.5 ± 0.8, P = 0.018), reinforcing the notion that, in the pandemic period, patients with more extended coronary artery disease may have not reached the hospital alive. The cases of OHCA which were transferred to our emergency room department by EMSs during the same period were nominally lower in the prepandemic compared with the postpandemic era (1.9 ± 1.7 vs 4.0 ± 4.6, P = 0.28, Supplementary Fig. 1B). Moreover, in the COVID-19 era, one patient (2.3%) developed a ventricular septal rupture after presenting delayed with a large anterior myocardial infarction. No mechanical complication had been witnessed in the pre-COVID-19 era.

Table 1

Baseline and hospital-related characteristics of study patients.

Variable	Prepandemic era (Ν = 141)	Pandemic era (Ν = 44)	P
Age, years	65.4 ± 12.1	65.8 ± 12.9	0.88
Male gender, %	83.7	75.0	0.19
Coronary artery disease, %	29.1	22.7	0.41
Dyslipidemia, %	54.6	45.5	0.29
Statin, %	45.4	22.7	0.007
Hypertension, %	57.4	45.5	0.16
Smoking, %			0.48
Current	41.8	34.1
Former	12.1	18.2
Chronic kidney disease, %	9.2	9.1	0.98
Diabetes mellitus, %	33.3	22.7	0.18
Serum creatinine, mg/dl	1.3 ± 1.4	1.5 ± 1.4	0.54
High sensitivity troponin T, pg/ml	2,242 ± 4030	1,742 ± 2,966	0.38
Total cholesterol, mg/dl	168 ± 43	185 ± 48	0.036
LDL cholesterol, mg/dl	99 ± 37	111 ± 37	0.067
HDL cholesterol, mg/dl	41 ± 14	40 ± 11	0.80
Left ventricular ejection fraction, %	51 ± 10	50 ± 10	0.64
ACS type, %			0.26
Unstable angina	15.6	15.9
NSTEMI	48.9	61.4
STEMI	35.5	22.7
Coronary angiogram performed, %	92.2	95.5	0.46
Diseased vessels, n	1.9 ± 1.0	1.5 ± 0.8	0.018
Mechanical complication, %	0.0	2.3	0.24
Outcome, %			0.99
Conservative	26.2	25.0
PCI	49.6	52.3
CABG referral	21.3	20.5
Death	2.8	2.3
Length of stay, days	5.9 ± 3.1	5.4 ± 2.9	0.54

* ACS: acute coronary syndrome; CABG: coronary artery bypass grafting; HDL: low density lipoprotein; LDL: low density lipoprotein; NSTEMI: non-ST-elevation myocardial infarction; STEMI: ST-elevation myocardial infarction; PCI: percutaneous coronary intervention.

In conclusion, the COVID-19 pandemic is associated with reduced numbers of ACS admissions, possibly due to the restrictive measures in healthcare facilities. Even so, the ACS patient profiles during the pandemic did not significantly differ, a fact implying that this trend was not guided by a true reduction in healthcare needs, but rather than to limited seeking of healthcare services on patients' end. The simultaneous increases in OHCAs corroborate, although do not prove, this hypothesis. Similar trends have been recently reported from New York City, USA, a region dramatically afflicted by the pandemic. The present study, however, is the first to provide hints on the potential unintended consequences of the pandemic in countries characterized by fewer COVID-19 cases and fatalities but prompt measures of social contact restrictions and lockdown. Future studies should address the impact of the pandemic on the population-level morbidity and mortality rates of such populations. Importantly, the rates of selected treatment modalities did not differ before and after the pandemic outbreak. Thus, contrary to what has been reported elsewhere, our data indicate that physicians' decision-making on the course of treatment in the setting of ACS was not affected by the pandemic. Nonetheless, this warrants confirmation in larger studies.

Author statements

Ethical approval

The study was approved by the Ethics Committee of our institution and was carried out in accordance with the Declaration of Helsinki.

Funding

The project was partially supported by an unrestricted grant from Hellas. Boehringer Ingelheim Hellas was not involved in the study design, roll-out, data collection, and data analysis.

Comepting interests

On behalf of all authors, the corresponding author states that there is no conflict of interest.