The SWISS PCI Survey—Coronary and Structural Heart Interventions in Switzerland 2020

Summary

For almost 35 years, the Swiss Working Group for Interventional Cardiology of the Swiss Society of Cardiology has evaluated and assessed the invasive diagnostic and therapeutic heart interventions performed annually in Switzerland. The aim of this survey, which was completed by 36 centres using a standardised questionnaire, was to report the data for the year 2020. Overall, 53,088 coronary angiographies with 48.8% subsequent percutaneous coronary interventions, i.e., 8.6% less than in 2019, were performed. Regarding structural interventions, there were 1790 transcatheter aortic valve implantations, with a decrease of 6.4% compared with 2019. This decrease was most likely due to the coronavirus disease (COVID-19) pandemic and its consequences on the Swiss healthcare system.

Introduction

Despite major improvements in diagnostic and therapeutic options, such as broad and early access to coronary angiography, cardiovascular disease including acute myocardial infarction remains the leading cause of death worldwide, with 176 million people dying per annum [1]. Therefore, current international guidelines highlight the importance of established international and national networks for the management of acute and chronic heart disease [2,3]. The Working Group for Interventional Cardiology of the Swiss Society of Cardiology (SSC) has coordinated the annual assessment of invasive diagnostic and therapeutic procedures performed in Switzerland since 1987 [4]. Based on a standardised questionnaire, the number of diagnostic and therapeutic procedures are self-reported by each centre and published by the Swiss Working Group for Interventional Cardiology of the SSC [5,6,7,8,9,10]. In contrast to previous years, the performed procedures in 2020 were influenced by the evolving coronavirus disease (COVID-19) pandemic.

Methods

We contacted all interventional cardiology centres in Switzerland and asked them to complete the standardised online questionnaire via the Survio® platform. In the case of technical difficulties or according to their preference, the questionnaire was completed using a standardised pdf-file. In total, we assessed 69 items including basic information on the catheterisation centres, and more specific details on the type and indications of interventions, material used and outcome (if available). Detailed information on the assessed variables is given in the online appendix.

Data were collected using Excel® for Windows® and we solely used descriptive statistics without formal statistical analysis. As no specific patient data were assessed, and as data collection and analysis for in-hospital mortality after interventional procedures were for quality assurance/control purposes only, no formal approval by local institutional review boards and/or written patient consent was required.

Results

In the year 2020, 36 of 38 (94.7%) Swiss centres with interventional cardiology available on site reported their numbers. Of note, the Herzklinik Hirslanden Zurich and HerzZentrum Hirslanden Zurich reported their numbers together as one centre. The Kantonsspital Baden and the Herz-Gefäss-Klinik Bethanien Zurich did not report any numbers. The participating centres consisted of 5 university hospitals, 15 non-university public hospitals and 16 private institutions. Centres from 17 of the 26 cantons of Switzerland participated. Sixteen (46%) of these centres have cardiac surgery on site with the possibility to perform procedures with surgical back-up (

Table 1. Interventional cardiology centres in Switzerland in 2020.

).

Diagnostic and interventional procedures for coronary heart disease

Overall, 205 percutaneous coronary intervention (PCI) operators performed 53,088 coronary angiographies (CAGs) in 65 catheterisation laboratories at 36 centres.

Of note, we observed a relative reduction in CAG cases of 8.4% compared with 2019. In 25,933 (48.8%) CAG cases, a subsequent PCI was performed (Figure 1), with a PCI per CAG rate ranging between 24% and 68% among different centres (

Table 2. Overall cases performed in 2020 versus 2019 and specific indications for percutaneous coronary interventions.

). The average number of total cases/year and PCIs/year per operator were 255 and 124, respectively (Table 1 and Table 2). The overall numbers of diagnostic and interventional cases per centre, ranked by absolute numbers, are shown in Figure 2. Similarly to 2019 [10], radial access was used in 66% of all cases. However, we still observed a wide range from 18% to 98%, depending on site and operator preference (

Table 3. Access route, stent types and balloons used.

).Thirty-two centres provided complete data on PCI indications. Among emergency PCIs (39% of total PCIs), non-ST-elevation acute coronary syndrome (NSTE-ACS), ST-elevation myocardial infarction (STEMI) and cardiogenic shock accounted for 59%, 37% and 4% of cases, respectively (Table 2). Interventions for chronic total occlusions (CTOs) accounted for 5.3% of PCIs and were primarily performed using an antegrade approach (65%). Among all coronary interventions, drug-eluting stents (DES) were the most used stent type at 99.7% of cases (bare metal stents 0.1%, self-expandable stents 0.1%, bioabsorbable scaffolds 0.2%, and bifurcation dedicated stents 0.1%; Table 3). The use of drug-coated balloons (DCBs) remained stable at 2.9% versus 2.8% of all cases in 2020 and 2019, respectively.

Lesion preparation using techniques other than balloon angioplasty were applied in 1937 cases (7.5% of all PCIs). Rotational atherectomy, intravascular lithotripsy, and thrombus aspiration were used in 345 (1.3%), 318 (1.2%), and 1274 (4.9%) cases, respectively (

Table 4. Revascularisation techniques, quantification methods, and use of left ventricular assist devices.

). The degree of coronary artery stenosis was further assessed in 6783 cases (12.9%) and quantified by fractional flow reserve (38.9%), instantaneous wave-free ratio (27.7%), intravascular ultrasound (10.9%) or optical coherence tomography (22.5%). Left ventricular assist devices were used in 468 cases (0.9% of all cases; Table 4).

Interventions for structural heart disease

For the first time since its clinical introduction in Switzerland in 2007 and similarly to CAG, cases of transcatheter aortic valve implantation (TAVI) decreased in 2020 compared with the preceding year. We observed an overall reduction of 122 interventions (-6.4%; Figure 3 and Figure 4). In 2020, 1790 TAVIs were performed with femoral access being used in 94% and trans-apical access in 2.7% of all implantations (

Table 5. Transcutaneous aortic valve implantations (TAVIs) in 2020 with details on access route and use of embolic protection devices.

).

Compared with previous years, we observed a further decrease in mitral edge-to-edge repair procedures from 362 in 2019 to 314 in 2020 (-13.3%,

Table 6a. Mitral and tricupid valve interventions.

a) [9,10]. Similarly, numbers of left atrial appendage (LAA) closures decreased from 317 to 305 (3.8%), and interventional persistent foramen ovale (PFO) closure procedures from 866 to 782 (-9.7%). Catheter-based therapy of pulmonary embolism was used more commonly in 2020 than in 2019 (125 versus 98 cases; Table 6a and

Table 6b. Specific interventional therapy and data on closure devices.

b).

Outcome

Among all participating centres, only 24 (69%) reported data on in-hospital mortality, thus making our findings less representative. Regarding interventions for chronic coronary artery disease, NSTE-ACS, STEMI, and cardiogenic shock, there was an in-hospital mortality of 0.08%, 1.6%, 4.1%, and 52%, respectively. The overall in-hospital mortality of patients undergoing a TAVI procedure was 2% (data reported by five centres only).

Limitations

There are some limitations that need to be highlighted: First, the main limitation results from the study design, with data being submitted on a voluntary basis by the individual centres without monitoring. We aimed to minimise this effect by sending a standardised questionnaire to all involved centres. Second, unfortunately not all centres replied and provided complete data. Due to missing data, some findings of this study are not representative, and their generalisability is limited. Third, definitions of chronic coronary artery disease, NSTE-ACS, STEMI, and cardiogenic shock were based on international guidelines but not predefined by the registry, and therefore may have differed among the centres. Fourth, when comparing the findings of 2020 with those from 2019 one has to consider that only 36 and not 37 centres participated. However, this had no impact on reported TAVI procedures as all Swiss TAVI centres participated in both years.

Conclusion

The national numbers of 2020, as collected by the Swiss PCI Survey, show a decrease in both cases for both coronary and as structural heart disease. Interestingly, TAVI cases decreased for the first time since 2007. Similarly, compared with 2019, we observed an 8.4% reduction in CAG and PCIs. These findings are well in line with several international studies that found a severe impact of the COVID-19 pandemic on the entire field of interventional cardiology and the number of heart interventions compared with preceding years [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16]. Fortunately, although we have observed a reduction, it was not as dramatic as reported elsewhere [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16]. Despite international recommendations, the number of cases with radial access remained stable at only 66%. Especially in times of the COVID-19 pandemic, radial access as the preferred route, which is known to be associated with lower complication rates and shorter hospital stays, might help to reduce the in-hospital resource use. Similarly, local versus general anaesthesia for TAVI could be beneficial, even though previous studies did not show a relevant reduction in the length of hospitalisation [17]. In order to further relieve strained hospital resources, a more liberal approach in identifying patients eligible for PCI or TAVI might be promising. Regarding TAVI procedures, the transfemoral approach was the commonly used access (98.2%). Numbers of other structural interventions, such as the mitral edge-to-edge repair, PFO and LAA occlusions remained stable on a high level. Despite the observed decrease in overall cases due to the COVID-19 pandemic, the presented data still show a comparable performance in interventional cardiology for Switzerland compared with its European neighbours [18,19,20,21].

As a result of a well-organised and functional national network of the Swiss Working Group for Interventional Cardiology, nationwide data were collected on interventions for coronary and structural heart disease. National registries and standardised data collection as well as publication remain a key tool to assess the performance of a healthcare system and confirm outcomes and safety of procedures in interventional cardiology [22,23].

Disclosure statement

No financial support and no other potential conflict of interest relevant to this article was reported.