With the advancements in interventional cardiology in the Republic of Croatia over the last two and a half decades, the goal of this study was to analyze the number and complexity of percutaneous coronary intervention (PCI) procedures in individual centers. Between 2010 and 2014, an average of 9,494 PCI procedures was performed annually in a total of 13 centers. Seven centers are classified as high-volume centers: the Magdalena Clinic with the highest number of PCI procedures performed annually, with an average annual increase of 6.2% (1545 to 1941 PCI over analyzed period), the University Hospital Centre (UHC) Zagreb with an average annual decrease of 1.8% in procedure numbers (1474 to 1308), UHC Rijeka with an average annual increase of 15.8% (1013 to 1632), University Hospital (UH) Dubrava with an average annual decrease of 5.7% (1153 to 905), and the UHC "Sestre milosrdnice” with an average annual increase of 2.3%; however this hospital experienced a decrease of procedures in the last year of period (1082 to 815). These are followed by the UHC Split with an average annual increase of 6.7% (662 to 821) and the UHC Osijek with an increase of 12.4% (677 to 905). Five centers are classified as medium-volume centers: the UH Merkur with an average annual decrease in PCI procedures of 3.7% (670 to 506), whereas the number of procedures increased in the rest of the medium-sized centers: in General Hospital (GH) Slavonski Brod by 29.1% annually (264 to 660), UH "Sveti Duh” by 7.5% annually (306 to 382), in the GH Zadar by as much as 70.5% annually (105 to 430), and in the GH Dubrovnik by 32.4% annually (84 to 232). In Croatia overall, the percentage of complex procedures on two or more vessels was 9.7%. It was highest in the UHC Rijeka (18.2%) and UH Dubrava (17.1%), followed by the GH Zadar (15.3%), UHC Split (11.0%), and the Magdalena Clinic (10.4%). The UHC Zagreb had a value similar to the national average (10.1%), as did the GH Dubrovnik (8.6%). Lower percentages of complex procedures were present in the UH "Sveti Duh” (7.9%), UHC "Sestre milosrdnice” (6.9%), and the GH Slavonski Brod (6.3%), whereas the lowest rate of complex procedures was found in the UHC Osijek (3.5%) and the UH Merkur (1.7%). With such advancements in coronary interventions and once the introduction of a registry of coronary interventions and certificates for centers and staff is completed, the next step in Croatia should be the introduction of a plethora of new procedures in patients with acquired or congenital structural heart diseases that are currently underdeveloped.
Analyzing the rate of percutaneous coronary interventions (PCI) is one of the fundamental determinants in the assessment of the level of cardiologic development. In addition to collection of epidemiological data on cardiovascular diseases on the population and hospital levels, this analysis is the basis for planning the allocation of material and human resources in cardiology and the health care system in general.
Past data indicate significant progress in interventional cardiology in the Republic of Croatia (RC) over the last two decades. For instance, the PCI rate in 2010 was 2,102 per million inhabitants, which is more than an average in OECD member countries (1,808) or EU21 countries (1,910). (
According to intervention volume, the following seven (54%) are classified as high-volume centers: Magdalena Clinic, UHC Zagreb, UH Dubrava, UHC "Sestre milosrdnice”, UHC Rijeka, UHC Split, and UHC Osijek. Medium-volume centers group consists of the following four (30.7%): UH Merkur, General Hospital (GH) Slavonski Brod, UH "Sveti Duh”, GH Zadar, and GH Dubrovnik, while the GH Karlovac performed only diagnostic procedures. (
The aim of this study was to analyze the number of PCI procedures in interventional centers in the period from 2010 to 2014 and assess their complexity, based on data from the Croatian Health Insurance Fund (CHIF). This is only a preliminary study, since the Croatian Registry of Cardiologic Interventions is currently being prepared and will, in addition to precise numerical data, contain internationally comparable indicators of performance and intervention complexity.
Data on the number of PCI procedures were gathered according to the CHIF claims for hospital treatment from 2010 to 2014. The research methodology, study limitations, and criteria for center classification based on annual PCI procedures into high-volume (more than 600) and medium-volume (from 200 to 600) centers have been previously described. (
When analyzing the complexity of PCI procedures, complex procedures were considered to be those under the following CHIF codes: percutaneous transluminal coronary angioplasty (PTCA) on two or more coronary arteries (CHIF code 35305-00) and percutaneous implantation of 2 or more transluminal stents into multiple coronary arteries (CHIF code 35310-02). This classification of complexity for coronary interventions has already been applied previously and is used in the National Cardiovascular Data Registry of the United States of America (the CathPCI Registry). (
From 2010 to 2014, seven Croatian centers fulfilled the classification criteria for high-volume centers: Magdalena Clinic, UHC Zagreb, UHC Rijeka, UH Dubrava, UHC "Sestre milosrdnice”, UHC Split, and UHC Osijek, where the number of PCI procedures was slightly below the high-volume threshold only in 2011 (n=526) (
Percutaneous coronary interventions (PCI) in seven Croatian high-volume PCI centers in 2010–2014.
Three centers had a medium number of PCI procedures both annually and on average: UH Merkur, GH Slavonski Brod, and UH "Sveti Duh”. The GH Zadar had more than 200 procedures annually on average and after 2012, whereas the GH Dubrovnik had more than 200 procedures annually since 2013 (
The Magdalena Clinic had the highest number of PCI procedures performed in all years, with an average annual increase of 6.2%. Of the high-volume centers, an average annual increase in PCI numbers was noted in the UHC Rijeka (15.8%), the UHC Osijek (12.3%), and the UHC Split (6.7%), whereas an average annual decrease in the number of PCI procedures was noted in the UHC Zagreb (1.8%) and the UH Dubrava (5.7%). The UHC "Sestre milosrdnice” had sharp decrease in PCI procedures performed in 2014, but the hospital experienced the average annual increase of 2,3% over observed period.
The relative ratio of PCI procedures in comparison with the previous year in high-volume centers is shown in
Annual change in frequency of percutaneous coronary interventions (PCI) compared with the previous year in seven Croatian high-volume PCI centers in 2010–2014.
Among the medium-volume centers, the UH Merkur had the highest number of annual PCI procedures at the start of the study period, at the level of a high-volume center (n=670); however, this center was the only one experiencing an average annual decrease in PCI procedures (3.7%). The number of interventions increased in all other centers. In the GH Zadar the average annual increase was 75%, and in 2012 the number of procedures performed was over 200. In the GH Dubrovnik the average annual increase was 32%, and although the annual average of PCI procedures during the study period was only 160, it was higher than 200 for the last two studied years with an average of 235. The GH Slavonski Brod saw a 29.1% increase, while the UH "Sveti Duh” had an average annual increase of 7.5%. Moreover, the UH "Sveti Duh” had the highest number of PCI procedures in the medium-volume group in 2012 and 2013, but a sharp decrease in the next year, 2014 (
Percutaneous coronary interventions (PCI) in five Croatian medium-volume PCI centers in 2010–2014.
Average annual change in frequency of percutaneous coronary interventions (PCI) in Croatian PCI centers in 2010–2014.
Annual change in frequency of percutaneous coronary interventions (PCI) compared with the previous year in five Croatian medium-volume PCI centers in 2010–2014.
The average percentage of complex PCI procedures in the RC from 2010 to 2014 was 9.7%. These complex interventions were most common in the UHC Rijeka (18.2%) and the UH Dubrava (17.1%). Above-average rates of complex procedures were noted in the GH Zadar (15.3%), the UHC Split (11.0%), and the Magdalena Clinic (10.4%), whereas they were similar to average in UHC Zagreb (10.1%) and GH Dubrovnik (8.6%) and less common in the UH "Sveti Duh” (7.9%), UHC "Sestre milosrdnice” (6.9%), and GH Slavonski Brod (6.3%). Low rates of complex procedures were found in the UHC Osijek (3.5%) and the UH Merkur (1.7%) (
The frequency of percutaneous coronary interventions (PCI) on two or more vessels in Croatian PCI centers in 2010–2014.
In the high-volume center group, the rate of complex PCI procedures grew over the study period in the UHC Osijek, remained similar in the UHC Rijeka and to an extent in the UH Dubrava, and went down in the UHC Split as well as dropping by more than half in the UHC Zagreb and UHC "Sestre milosrdnice” (
The frequency of percutaneous coronary interventions (PCI) on two or more vessels in Croatian high-volume PCI centers in 2010–2014.
The percentage of complex PCIs in medium-volume centers is shown in
The frequency of percutaneous coronary interventions on two or more vessels in Croatian medium-volume PCI centers in 2010–2014.
Interventional cardiology in the RC experienced significant progress over the last two and a half decades, which is supported by numerical indicators. The PCI rate of 474 per million inhabitants in 2001 was two and a half times lower than the European average (1,267), three times lower than in Austria (1,494), and lower than in the transitional countries analyzed at the time: the Czech Republic (1,171), Slovenia (599), and Hungary (522). (
Most centers in Croatia, as many as seven (54%), are classified as high-volume centers and five (38%) as medium-volume centers. (
Comparing the total annual number of PCI procedures in the high-volume centers with the previous year, there is a notable drop in PCI procedures of 11% in 2011, followed by a 26% increase in 2012. This is followed by a period of relatively stable PCI numbers in these centers. However, stable average numbers in the high-volume centers include significant yearly oscillations in some centers on an annual basis. For instance, the UHC "Sestre milosrdnice” saw a 44% decrease followed by an 81% increase, and the UHC Rijeka had a 65% increase in 2014. The reasons for these large yearly oscillations, both positive and negative, are likely to be found at the local level. The oscillations could be the result of the redistribution of resources within hospitals or the allocation of invasive cardiologists to other tasks, for instance work in general cardiologic outpatient offices or laboratories for non-invasive testing, in order to reduce the waiting lists in line with the policies of the Ministry of Health. Furthermore, the influence of the introduction of a national tender for consumables for cardiologic interventions have yet to be assessed, as well as changes in hospital administration during the process of hospital financial recovery and their position towards interventional cardiology.
Of the total 47,470 PCI procedures in the RC from 2010 to 2014, 18.5% i.e. 8,767 were performed in five medium-volume centers. The total volume of all medium-volume centers is comparable to the volume of the private Magdalena Clinic. However, despite this ratio, medium-volume centers have an extremely important place in the Croatian Primary PCI Network in the treatment of patients with acute coronary syndrome. Over the last decade, more than 15,000 patients with ST-segment elevation myocardial infarction (STEMI) have been treated in this network. More and more centers joined the network over this period, and today cardiologists in eleven PCI centers work 24/7, caring for on average 384,000 inhabitants per center and annually treating and managing 540-550 patients with STEMI per million inhabitants. (
The Croatian Primary PCI Network does not include the UH Merkur, which is classified as a medium-volume center, despite the fact that at the start of the study period it fulfilled the criterion for a high-volume center with 670 PCI annually. However, this was the only medium-volume center with an average annual decrease in PCI procedures (of 3.7%), while all other centers showed average annual increase, highest in the GH Zadar (70.5%), followed by the GH Dubrovnik (32.4%) and GH Slavonski Brod (29.1%), which approached the criterion for a high-volume center with 660 procedures in 2014. The reasons for the reduction in the number of interventions in the CH Merkur and the increase in the other medium-volume centers are yet to be investigated, as well as the reasons for significant fluctuations in some centers, for instance the UH "Sveti Duh” that had the largest number of PCI procedures in the medium-volume group in 2012 and 2013, only for that number to drop sharply in 2014. There was also a noticeable increase in the number of PCI procedures in comparison with the previous year in 2012 in the GH Zadar, in the GH Dubrovnik in 2013, and in the GH Slavonski Brod in 2014. In addition to local hospital policies, according to personal contacts, this increase can be partially explained in some centers by the arrival of younger colleagues from their cardiology residence and in others by the employment of experienced cardiologists from other centers, and the technical completion of some laboratories.
In addition to a precise count of performed procedures, indicators of performance and intervention complexity will certainly be important parameters in the future national registry of cardiologic interventions, which will allow comparison with international data, precise evaluation of work, and improvement of clinical practice. Currently the complexity of the performed PCI procedures can be estimated solely on a single criterion – the ratio of concurrent procedures on two or more coronary arteries. This criterion is well-established in the literature and is for instance, in addition to other criteria, applied in the National Cardiovascular Data Registry of the United States of America (the CathPCI Registry). (
The introduction of a national registry of cardiologic procedures will be the crowning achievement of this phase of the development of cardiology in Croatia, which has come close to the very best in Europe in coronary intervention results. Further steps will surely include standardization, which assumes the establishment of criteria and certification of institutions and laboratory staff. In contemporary interventional cardiology at the global level, there has been significant progress in a range of new procedures in patients with acquired structural heart diseases and patients with adult congenital heart disease, which are, as opposed to coronary interventions or transplantation medicine, still underdeveloped in our country. The list of these new procedures is long (
Transseptal left heart catheterization |
Closure of the patent foramen ovale |
Forming teams to conduct these procedures in Croatia will represent a great challenge not only for the Croatian Cardiac Society and the Working Group on Interventional Cardiology, but also for the Ministry of Health, CHIF, and other providers of medical services. A significant role in planning will be taken up by financial resources on the one hand and the quality level of comprehensive care in individual centers on the other, including radiology, cardiac surgery, and vascular surgery. However, the most important factors in planning are epidemiological data, which are currently not available in Croatia. We will thus have to use European statistics at the start while simultaneously developing registries for these two groups of diseases. Based on these data, it will be possible to assess which procedures are not reasonable or cost-effective to perform in our country and send these patients to other centers abroad, such as, as an example and according to our personal opinion, transcatheter pulmonary valve implantation (TPVI), whereas other procedures will require a careful assessment of whether there is even a need to develop a single center for the procedure in the RC (for instance, closure of pulmonary vascular malformations and aortopulmonary collaterals). Other procedures will perhaps require only a single center in the country, for instance ventricular septal ablation. However, we are already significantly lagging in the development of some of the procedures listed in