The relationship between hospital or operator volume and outcomes of coronary patients undergoing percutaneous coronary interventions.

The relationship between volume and outcome in medicine has been intensively investigated in the last few decades. The large amount of accumulated data demonstrates that for many surgical or non-surgical procedures and medical conditions, patients being treated in high-volume hospitals or by high-volume physicians have lower mortality rates and better quality of life compared to those treated by low-volume hospitals or by low-volume physicians. Although the degree of the relationship between high volume and better outcome varies, it is persistent across a wide range of procedures and conditions. Percutaneous coronary interventions (PCIs) have an important impact on public health, given the frequency of coronary heart disease for which these procedures are performed. Studies carried out before and after the advent of stents on the relationship between volume and outcome for PCIs have almost consistently reported that performance of PCIs in high-volume institutions or by high-volume operators is associated with improved outcomes for patients, regardless of the specific indication for PCI. For those procedures for which a relationship between high volume and better outcome has been clearly demonstrated, patients as well as their referring physicians should be informed that patients can benefit both in terms of reduced mortality and improved quality of life if they are treated by high-volume health care providers. Consequently, for these procedures, a health care policy aiming at their concentration in high-volume institutions should be strongly considered.