Background. Coronavirus disease 2019 (COVID-19) pandemic had an impact on the quality of healthcare services and led to many changes in the treatment of cardiac pathologies.
Objectives. To assess the differences in the clinical manifestations, management and outcomes of patients with aortic valve diseases (AVDs) treated invasively before and during the pandemic.
Materials and methods. This retrospective single-center study involved patients with AVDs treated by means of balloon aortic valvuloplasty (BAV), transcatheter aortic valve implantation (TAVI) or surgical aortic valve replacement (SAVR) in 2019 and 2020. They were divided into groups with respect to the year of intervention (2019 compared to 2020) and the priority of admission (urgent compared to elective). Preoperative characteristics, early outcomes and probability of annual survival were compared between the groups.
Results. The number of patients admitted urgently increased from 37 in 2019 to 54 in 2020, with a higher prevalence of men in 2020 (83.3% compared to 56.8%, respectively). Elective cases, on the other hand, declined from 279 in 2019 to 256 in 2020. Among the latter, more subjects had manifestations of heart failure (p < 0.001), coronary artery disease (CAD; p = 0.002), hypertension (p = 0.006), as well as had a history of a stroke (p = 0.002). In the meantime, more TAVI and fewer SAVR procedures were performed in 2020 (86 compared to 127 and 192 compared to 125, respectively; p < 0.001). In 2020, TAVI individuals had risk of death (according to the EuroSCORE scale) than in 2019 (p < 0.001). The probability of annual survival was comparable (p = 0.769) among AVD patients treated before and during the coronavirus pandemic (91.3% compared to 88.3%, respectively).
Conclusions. Although during the COVID-19 pandemic more nonelective and higher-risk AVD individuals received interventional treatment, the outcomes were comparable to the pre-pandemic era (2019). Our findings support highly valuable, less invasive therapeutic methods for treating aortic pathologies during the pandemic.
Key words: outcomes, coronavirus, aortic valve replacement, transcatheter aortic valve implantation, aortic valve disease
Coronavirus disease 2019 (COVID-19) pandemic has affected healthcare systems globally. Consequently, the number of admissions to general hospitals1, 2 and cardiology departments in particular decreased markedly.3, 4 Hence, a reduction in the number of cardiology services and procedures, especially elective cases, has been observed.3, 5, 6 A marked decline in the majority of cardiac procedures performed at National Health Service (NHS) hospitals (in the UK) was obvious after the pandemic outbreak.6 A similar trend was also observed in Poland.7, 8
In the meantime, special attention was paid to minimizing hospitalization times of patients and shifting to minimally invasive procedures, although these were not always considered the method of choice.9 This trend was observed in many prevalent cardiac diseases such as aortic valve diseases (AVDs), aortic stenosis (AS) and coronary artery disease (CAD) that can be potentially treated by either interventional cardiologists or cardiac surgeons. Patients with AS can be treated surgically with cardiopulmonary bypass (CPB) and surgical aortic valve replacement (SAVR), or by transcatheter aortic valve implantation (TAVI).10
This study aimed to assess how the COVID-19 pandemic affected the clinical profiles, priority of treatments, form of applied therapeutic methods, and outcomes of patients with AVD, treated at a cardiac surgical center experienced in both SAVR and TAVI procedures.
Materials and methods
This retrospective study evaluated consecutive patients treated for significant AVD between January 1, 2019, and December 31, 2020, at the Department of Cardiac Surgery and Transplantology in Poznań, Poland. The groups were divided based on the year (2019 – before the coronavirus pandemic outbreak, compared to 2020 – after the outbreak) of admission, the method of treatment (SAVR compared to TAVI) performed, and the priority of the intervention (elective compared to nonelective – urgent/emergent). Medical charts were retrospectively reviewed and baseline data (Table 1, Table 2) were collected and analyzed.
Patients were treated with SAVR (218 in 2019 and 168 in 2020) using a complete or upper partial median sternotomy and CPB with cardioplegic arrest. Some patients required additional procedures (see Table 1). Catheter-based methods included TAVI carried out through percutaneous puncture or surgical exposure of the femoral arteries (91 in 2019 and 134 in 2020) and balloon aortic valvuloplasty (BAV; 7 in 2019 and 8 in 2020).
Early morbidity and mortality as well as annual survival probability were taken into consideration. Early or in-hospital outcome analysis during the first 30 days after the procedures irrespective of place (hospital, rehabilitation center or home) was performed.
The normality of continuous variables was checked using the Shapiro–Wilk test. Data that met the criteria of normal distribution were shown as means with standard deviations (SDs). Non-normal data were presented using medians with interquartile ranges (IQRs: Q1–Q3). The Levene’s test was used to assess the equality of variances between normally distributed data from 2019 and 2020. Student’s t-tests were used to compare unpaired continuous variables. The other variables were compared using a nonparametric Mann–Whitney U test and a χ2 test with or without Yates’s correction. Statistical significance was defined as p < 0.05. The probability of survival was calculated using the Kaplan–Meier method and the differences between the groups were analyzed using a log-rank test. The analysis was performed with Statistica v. 13.3 (TIBCO Software Inc., Palo Alto, USA).
The number of individuals with severe AVD treated invasively remained virtually unchanged between 2019 (n = 316) and 2020 (n = 310). A significant increase in the number of nonelective cases was observed (from 37 in 2019 to 54 in 2020).
and procedural details
The only difference in the preprocedural clinical presentation (2019 compared to 2020) was the age of the patients (Table 2). The most visible change in nonelective procedures was a marked increase (by 65%) in SAVR cases (26/43) which corresponded with an increase of roughly 10% overall (Figure 1). The rate of concomitant procedures in the SAVR subset of patients was comparable between years (2019 compared to 2020). More detailed data are outlined in Table 1.
Similar to nonelective patients, there was a difference (2019 compared to 2020) in the age of elective patients (Table 2). In this group, a significant shift from SAVR being the dominant procedure in 2019 to a slight predominance of TAVI in 2020 occurred (Figure 1). Moreover, some comorbidities such as CAD, arterial hypertension and history of stroke were significantly more common in 2020 (Table 2).
and one-year probability of survival
Atrial fibrillation was the only early post-procedural adverse event that was found to be more prevalent in 2019 than in 2020 among AVD individuals admitted electively to our department. In the urgent/emergent group of patients, the rates of all in-hospital complications were comparable between the compared years.
A total of 22 patients died during the early post-procedural period. However, the overall mortality in patients undergoing procedures on the aortic valve was almost twice as high in 2020 (4.5%; 14/310) as compared to 2019 (2.5%; 8/316; p = 0.178). In the elective subgroups, in-hospital mortality was 2.2% (n = 6) in 2019 and 3.5% (n = 9) in 2020, whereas among urgently/emergently treated patients, it was 5.4% (n = 2) in 2019 and 5.6% (n = 5) in 2020.
The survival rate for all patients treated invasively for AS was comparable between 2019 and 2020 groups (p = 0.769). Three-month, 6-month and 1-year survival probabilities for patients in 2019 compared to 2020 were calculated using the Kaplan–Meier method and were found to be 95.2% (295 patients at risk) compared to 93.6% (265 patients at risk), 93.4% (273) compared to 90.5% (255), and 91.3% (266) compared to 88.3% (248), respectively. Statistically significant differences were observed among TAVI- and SAVR-treated patients during the consecutive years. In 2020, the annual survival rate was higher among TAVI patients and lower in SAVR patients compared to the survival rates in 2019 (Figure 2).
One of the most important findings of this study was a significant increase in the number of urgently/emergently admitted AVD individuals accompanied by a marked decline in elective admissions. Our observations were not consistent with previously published studies that indicated a reduction in the number of invasive interventions for cardiovascular diseases, irrespective of priority (elective/nonelective), by roughly 50% in the UK.4, 5, 6, 7, 8 A reason for this discrepancy and the increase in the number of nonelective patients in our observational study was the conversion of a second cardiac surgery center in the area, with a similar volume of cases during previous years, into a facility dedicated to the treatment of COVID-19 patients in 2020.
Among elective patients, a significant decrease in the number of SAVR operations and an increase in TAVI procedures were observed. This tendency has been seen for many years.11 In 2020, the numbers of SAVR and TAVI procedures were almost equal. The shift to less invasive procedures was associated with a decline in the length of hospitalization12 and may be linked to reduced exposure to medical personnel.13, 14 For these reasons, the TAVI procedure could prove to be more effective during the pandemic.
In elective patients who received SAVR, men remained the prevalent group. Women underwent slightly more TAVI procedures and this tendency was seen in the following years. Besides the typical risk factors for AVD development such as arterial hypertension, hyperlipidemia and smoking (in many countries more prevalent in middle-aged men), women tended to underreport the manifestations of the disease15 and/or avoid healthcare staff.16 Moreover, some patients may have developed or aggravated their conditions because of a diagnosis of COVID-19 seen in their medical histories.17, 18, 19, 20
No statistical differences in the baseline clinical status of patients were found between the compared years in the urgent/emergent group. However, one cannot exclude that this was probably due to the relatively low number of such patients (37 and 54 cases). In the urgent/emergent patients, 6 of them during 2020 only required the replacement of a previously implanted aortic valve prosthesis (there were no such cases in 2019). These replacements were mainly due to secondary infective endocarditis and paravalvular leaks.
In our study, some interesting findings regarding the mortality rate were noted, e.g., improved survival after TAVI compared to a worse survival after SAVR procedures. Some research has indicated that the mortality rate of elderly patients after TAVI was similar to that of younger patients.21 Other publications have shown the survival in elderly patients after TAVI to be similar to the survival in an age-matched general population.22, 23 In our study, we revealed that the experience of our team resulted in a very good survival rate.
We are aware of some limitations of our study. First of all, it was a retrospective analysis and the nonelective subgroups were relatively small. Despite the aforementioned facts, some findings were of clinical significance.
Despite the fact that during COVID-19 pandemic more nonelective and high-risk AVD individuals received the interventional treatment, the outcomes were comparable to the pre-pandemic era (2019). Our findings support the value of less invasive therapeutic methods for aortic pathologies during the pandemic.