Background: The ALKK registry contains about 20% of the invasive and interventional cardiological procedures performed in Germany.
Methods: In 2003 a total of 82,282 consecutive diagnostic invasive and 30,689 interventional procedures from 75 hospitals were centrally collected and analyzed.
Results: The main indication for an invasive diagnostic procedure was coronary artery disease in 92.5% of cases, myocardial disease in 1.6%, impaired left ventricular function in 4.0%, valve disease in 4% and other indications in 1.9%. An acute coronary syndrome was present in 25% of the patients. The rate of severe complications in patients with a lone diagnostic invasive procedure was low (<0.5%). The indication for percutaneous coronary intervention (n=30,689) was stable angina in 44.1%, ST elevation myocardial infarction in 22.3%, non ST elevation myocardial infarction in 14.8%, unstable angina in 10.0%, silent ischemia in 2.2%, prognostic in 5.2% of patients. The majority of interventions were performed directly after the diagnostic procedure (n=23,887=78.6%). The intervention was successful in 94.6% of cases. Stent implantation was performed in 77.2%, with 1 stent in 88.4%, two stents in 7.6% and 3 or more stents in 3.3%. A drug-eluting stent was implanted in 3.6% of the cases. The complication rate after PCI was influenced by the indication for the intervention. The in-hospital mortality in patients with cardiogenic shock was 33%, while in patients with stable angina, silent ischemia and prognostic indication only 0.2% died.
Conclusion: There is an increase of invasive diagnostic and interventional procedures in patients with acute coronary syndromes, with 47% of PCIs performed in these patient. PCIs were performed in 75% of the cases directly after the diagnostic procedure. The rate of stent implantation seems to have reached a plateau at around 80%, while drug-eluting stents were implanted only in a minority of cases. The complication rate is mainly dependent on the clinical presentation of the patients and the indication for PCI.