Purpose: To evaluate potential changes in clinical indications and the composition of the patient population undergoing percutaneous coronary intervention (PCI) in Iceland from 1987 to 1998. Furthermore, to assess changes in success rate and major complications for the procedure during the study interval in a small nation with one PCI centre.
Material and methods: The first PCI was performed in Iceland in May 1987. A registry has been kept from the start that includes clinical and procedural data, and records of complications and mortality. During the study interval a total of 2440 PCIs were performed. The annual procedure rate was low at first, with a steep rise during the last years. Based on procedural changes over the years the study interval was divided into three periods: I. 1987-1992 (471 procedures); the learning years, II. 1993-1995 (796 procedures); increasing number of PCIs and the method established, III. 1996-1998 (1173 procedures); increasing use of stents and new antiplatelet regime used.
Results: From period I to III, the rate of elective PCI declined from 82% to 52% (p<0.001), subacute procedures increased from 14% to 44% (p<0.001), acute PCI from 0.8% to 3% (p<0.05), and ad hoc procedures from 0.4% to 28% (p<0.001). This reflects an increase in PCI on patients with acute coronary syndromes, as the ratio of patiens with unstable angina increased from 15% to 36% (p<0.001). Also, 1-vessel PCI decreased proportionally from 93% to 83%, while 2 and 3 vessel procedures increased from 7% to 17% (p<0.001). The proportion of patients 70 years or older increased from 7% to 27% (p<0.001). Still, the success rate for PCI increased from 83% to 93% (p<0.001) and the use of stents rose sharply from 0% to 56%. The ratio of PCI due to restenosis declined somewhat between period II and III, from 15% to 12% (p=0.06). Simultaneously, the rate of acute coronary bypass surgery after PCI decreased from 4.2% to 0.2% (p<0.001) and significantly fewer patients had elevated creatinine kinase levels (4.0% vs 2.7%, respectively, p<0.05). However, clinical acute myocardial infarction after PCI remained similar at 1.3% and 0.9%, and the in hospital mortality was 0.6% and 0.4%.
Conclusions: On a national basis the rate of PCI in Iceland is amongst the highest in Europe. Thus, in 1998, when the population in Iceland was 275,000, 453 PCIs were done (1647 procedures per million inhabitants). An increased number of subacute and acute PCIs is carried out, more complicated procedures are performed in patients with widespread disease, and the patient population is growing older. Still, the success rate is high and the frequency of complications and mortality relatively low.