Background: This review concerns the putative benefit of percutaneous coronary intervention (PCI) over optimal medical therapy (OMT) for symptomatic patients with stable angina pectoris, or for asymptomatic persons in whom screening tests have revealed coronary heart disease (CHD; this entity has been newly designated chronic coronary syndrome, or CCS). Moreover, it addresses the question whether the indications for which PCI is now performed in Germany on patients with CCS are consistent with current scientific knowledge.
Methods: The pathophysiological concept of CHD and ischemia induction is discussed in the light of the scientific literature. This concept implies that PCI might be beneficial in the treatment of CCS. The benefit of PCI over OMT has now been evaluated in seven randomized trials (the so-called milestone trials). The current situation in Germany is presented here as well, on the basis of the available data.
Results: The pathophysiological concept of CHD implies that the particular coronary artery stenoses that are likely to give rise to a myocardial infarction (the so-called vulnerable plaques) cannot be identified prospectively with current methods. Moreover, a coronary artery stenosis will not necessarily cause myocardial ischemia. All of the randomized trials carried out to date that have compared OMT to PCI-plus-OMT in patients with CCS have led to the conclusion that PCI, because it focuses on individual coronary artery stenoses, cannot prolong survival or lower the incidence of myocardial infarction over the long term. This remains the case even if a single coronary artery stenosis is known to be causing moderate or severe myocardial ischemia (a conclusion of the ISCHEMIA trial). A PCI performed only because the coronary stenosis or stenoses meet certain morphological criteria, without any demonstration of a resulting functional disturbance, is generally detrimental to the health of the patient, with rare exceptions, and is inconsistent with the recommendations of current guidelines. The number of PCIs being performed in Germany at present is high compared to other countries; this arouses concern that the indications for it may be dubious in many cases.
Conclusion: Current data imply that PCI for CCS does not improve outcomes in a large percentage of cases. A symptomatic benefit exists only in patients with frequent angina pectoris. The selection of CCS patients for PCI needs to be more strictly bound to the recommendations of current guidelines, particularly in Germany.