COVID-19 Pandemic Impact on Percutaneous Coronary Intervention for Acute Coronary Syndromes: An Australian Tertiary Centre Experience

Abstract

Background: Countries who suffered large COVID-19 outbreaks reported a decrease in acute coronary syndrome (ACS) presentations and percutaneous coronary intervention (PCI). The impact of the pandemic in countries like Australia, with relatively small outbreaks yet significant social restrictions, is relatively unknown. There is also limited and conflicting data regarding the impact on clinical outcomes, symptom-to-door time (STDT) and door-to-balloon time (DTBT).

Methods: Consecutive ACS patients treated with PCI were prospectively recruited from a tertiary hospital network in Melbourne, Australia. The pre-pandemic period (11 March 2019-10 March 2020) was compared to the pandemic period (11 March 2020-10 May 2020) using an interrupted time series analysis with a primary endpoint of number PCI-treated ACS per day. Secondary endpoints included STDT, DTBT, total mortality and major adverse cardiac events (MACE).

Results: A total 984 ACS patients (14.8% during the pandemic period) received PCI. Mean number of PCI-treated ACS per day did not differ between the two periods (2.3 vs 2.4, p=0.61) with no difference in STDT [+51.3 mins, 95% confidence interval (CI) -52.4 to 154.9, p=0.33], 30-day mortality (5% vs 5.3%, p=0.86) or MACE (5.2% vs 6.1%, p=0.68). DTBT was significantly longer during the pandemic versus the pre-pandemic period (+18.1 mins, 95% CI 1.6-34.5, p=0.03) and improved with time (slope estimate: -0.76, 95% CI -1.62 to 0.10).

Conclusions: Despite significant social restrictions imposed in Melbourne, numbers of ACS treated with PCI and 30-day outcomes were similar to pre-pandemic times. DTBT was significantly longer during the COVID-19 pandemic period, likely reflecting infection control measures, which reassuringly improved with time.

Keywords: Acute coronary syndrome; COVID-19; Pandemic; Percutaneous coronary intervention.

Figure 1

Time series of PCI number per day pre- and post-pandemic period with estimated slopes for the pre-pandemic period and pandemic period. Legend: There was no difference in number of PCI per day between the pre-pandemic and pandemic periods (2.3 vs 2.4, p=0.61) on interrupted time series analysis. The rate of change of PCI per day within each period was also similar (slope ratio=1.002, [CI]: 0.998–1.006, p=0.45). 11 March corresponds to when COVID-19 was declared a pandemic by the World Health Organization (WHO). Abbreviation: PCI, percutaneous coronary intervention.

Figure 2

Interrupted time series analysis of median STDT per day pre- and post-pandemic period with estimated slopes. Legend: 446 and 85 STEMI patients met the inclusion criteria for symptom to door time analysis in the in the pre-pandemic and pandemic periods respectively. There was no statistically significant difference in STDT on interrupted time series analysis between the two periods (difference in midpoint estimates: +51.3 min, 95% CI -52.4 to 154.9, p=0.33). There was also no significant difference in the rate of change in STDT throughout the course of each period (slope ratio=0.44, [CI]: -4.24 to 5.11, p=0.85). Abbreviations: STEMI, ST elevation myocardial infarction; STDT, symptom-to-door time.

Figure 3

Time series of median DTBT per day pre- and post-pandemic period with estimated slopes. Legend: There were 246 STEMI patients in the pre-pandemic period and 44 in the pandemic period who met the criteria for inclusion in the DTBT analysis. DTBT was significantly increased during the pandemic period (difference in the mid-point estimate: 18.1 min [95% CI 1.6–34.5, p=0.03]). The prolongation in DTBT during the pandemic period was greatest at the beginning of this period and improved with time (slope estimate: -0.76, 95% CI -1.62 to 0.10). Abbreviations: DTBT, door-to-balloon time; STEMI, ST elevation myocardial infarction.

Supplemental Figure 1