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Outcomes of surgical treatment for active infective endocarditis under COVID‐19 pandemic

Abstract Background The coronavirus disease 2019 (COVID‐19) pandemic has been and will continue to be a challenge to the healthcare system worldwide. In this context, we aimed to discuss the impact of the COVID‐19 pandemic on the diagnosis, timing, and prognosis of surgical treatment for active infective endocarditis (IE) during the pandemic and share our coping strategy. Methods A total of 39 patients were admitted for active IE in the year 2020. The number of the same period last year was 50. Medical information of these two groups was extracted from our surgical database. Data were compared between the two groups and differences with or without statistical significance were discussed. Results In the pandemic year, we admitted fewer transferred patients (64.1% vs. 80%, p = .094). Timespan for diagnosis were prolonged (60 vs. 34.5 days, p = .081). More patients were admitted in emergency (41% vs. 20%, p = .030) More patients had heart failure (74.4% vs. 40%, p = .001), sepsis (69.2% vs. 42.0%, p = .018), or cardiogenic shock (25.6% vs. 8.0%, p = .038). Overall surgical risk (EuroSCORE II) was higher (4.15% vs. 3.24%, p = .019) and more commando surgery was performed (7.7% vs. 2.0%, p = .441). However, we did not see more postoperative complications, and early mortality was not worse either (0 vs. 4%, p = .502). Conclusions The negative impact of the COVID‐19 pandemic on the clinical practice of surgical treatment for active IE was multifaceted. However, with the preservation of the effectiveness of multidisciplinary IE surgical team, the early outcomes were comparable with those in the normal years.

the issue of infective endocarditis (IE) should not be neglected under the COVID-19 pandemic. IE is associated with a mortality rate of more than 20%, and 50% when surgery is indicated and not performed. 2,3 An accurate diagnosis and timely surgical decision are extremely important for reducing the mortality of IE. Our study aims to discuss the impact of the COVID-19 pandemic on the diagnosis, surgical timing, and early prognosis of surgical treatment for active IE during the pandemic year and share our experience.

| PATIENTS AND METHODS
Peking Union Medical College Hospital (PUMCH) is located in Beijing.
As the capital of China, the situation here has been grim for the prevention and control of COVID-19. During the past year, provinces like Hubei have been temporarily classified as high-risk districts. Transfer of patients from high-risk districts was either obstructed or delayed.
Under these circumstances, our coping strategy for the practice of IE surgery is described in Figure 1. As a febrile illness, IE outpatients were screened for COVID-19 with quantitative real-time polymerase chain reaction (qRT-PCR), IgG/IgM antibodies, and chest computerized tomography (CT) before admission. For patients with high body temperature, the COVID-19 screening was done in specialized fever clinics where a rapid response team for COVID-19 consisted of specialists from infectious, respiratory, intensive care, and anesthesiology department and an extracorporeal life support team was ready for initiation. The patient would be quarantined, and the rapid response team would be initiated immediately if the diagnosis of COVID-19 infection was confirmed. Otherwise, if COVID-19 was excluded, patients were allowed to be admitted. After admission, the routine preoperative workup for IE like echocardiography, coronary computerized tomography angiography (CTA), or head CT was performed.

| RESULTS
The pandemic of COVID-19 broke out in the winter of 2019, and the severity of the epidemic in China peaked in February 2020. The nationwide social distancing policy and traffic restriction policy for high-risk districts managed to subdue the increasing spread of the total number of confirmed COVID-19 cases. However, the number of newly admitted IE patients per month was stable despite the changing situation of the pandemic nationwide ( Figure 2).
Thanks to the strict prevention and control measures, no COVID-19 infection was confirmed among our IE surgical patients (Table 1). However, the practice of diagnosis and surgical treatment for active IE was impacted in multiple aspects. Diagnosis efficiency seemed to be impacted by the COVID-19 pandemic. The interval between the first symptom onset and the definite diagnosis of IE was longer in the 2020 group (60 vs. 34.5 days), though the difference was not significant (p = .081). Patients' admission was also impacted, the absolute number of IE patients who underwent cardiac surgery in the COVID-19 pandemic year was 39, less than 80% of that of the year 2019, which was 50. This year we admitted more native patients than the year 2019, while fewer referral patients were transferred from provinces outside Beijing (64.1% vs. 80%, p = .094). Moreover, the rate of emergency admission this year was statistically higher than that of the last year (41% vs. 20%, p = .030). Detailed patients' characteristics are listed in Table 1 42.0%, p = .018) and cardiogenic shock (25.6% vs. 8.0%, p = .038) before surgery. The percentage of IE with only echocardiography F I G U R E 2 Graphical representation of the accumulative number of patients who underwent surgeries for active IE, with the accumulation of total COVID-19 cases and COVID-19-related deaths nationally. The pandemic was most serious around February, while the monthly increase of IE surgical cases was steady. COVID-19, coronavirus disease 2019; IE, infective endocarditis features of valve malfunction other than symptomatic HF was significantly lower in 2020 (23.1% vs. 58.0%, p = .001). The percentage of local cardiac and embolic complications did not show significant differences between the two groups.
Although symptoms were more severe for the 2020 group, the surgical decision and timing were similar between the two groups. Information about surgery is listed in Table 2. The commonest indication for cardiac surgery was valve malfunction with or without HF, seen in 87.2% of patients in 2020 and 90% in 2019. More patients underwent surgery due to persistent infection in the pandemic year than in 2019 (28.2% vs. 12.0%, p = .054). We assessed the surgical risk preoperatively using the European System for Cardiac Operative Risk Evaluation II (EuroSCORE II) and Carlson Comorbidity Index. The EuroSCORE II of 2020 patients were significantly higher than that of 2019 patients (4.15% vs. 3.24%, p = .019) were impacted in many aspects. First, the nationwide social distancing policy and traffic restriction policy targeted to high-risk districts constituted a barrier to patients seeking medical care and interhospital transport. Patients with high body temperature had to undergo COVID screenings repeatedly during their referral process before they got the definite diagnosis of IE. As a result, the start of intravenous antibiotics treatment and the diagnosis of IE could be delayed, and the general condition of patients could be worse at admission. Second, as a febrile disease, the differential diagnosis from COVID-19 was necessary whenever patients present new onset of fever during the treatment after the diagnosis of IE, which means Difference between the two groups was not statistically significant but was considered potentially meaningful and was also discussed. b Difference between the two groups was statistically significant.

F I G U R E 3
Mann-Whitney U test was conducted for continuous variables, indicating that the timespan for diagnosis was prolonged (60 vs. 34.5 days, p = .081). Surgical timing was not impacted (6 vs. 6 days, p = .656), while surgical risk (EuroSCORE II) raised significantly (4.15% vs. 3.24%, p = .019). Charlson comorbidity score was similar between the two groups

| STUDY STRENGTHS AND LIMITATIONS
This retrospective study summarized and analyzed the impact of the COVID-19 pandemic on the diagnosis, indication, timing, risk, and early prognosis of surgical treatment for active IE during the past year and proposed our coping strategy. However, the study is limited by its retrospective nature. As a single-centered retrospective study, all our patients were diagnosed, operated on, and cared perioperatively by our multidisciplinary team in PUMCH. Moreover, we must be aware of the uncertainty around this evolving pandemic and the regional variability around the world. All these factors may reduce the credibility and impact the extrapolation of our conclusions.

| CONCLUSIONS
The negative impact of the COVID-19 pandemic on the clinical practice of surgical treatment for active IE was multifaceted. The diagnosis, early treatment, and referral for IE patients were delayed by the pandemic.
Patients admitted to referral centers were in more critical condition.
Overall surgical risk raised significantly and more high-risk surgeries like the commando surgery were performed. However, with the preservation of the effectiveness of multidisciplinary IE surgical team through online meetings, and by adhering to the principle of early surgery for active IE, the early outcomes were comparable with those in the normal years.