Volume and Outcome

Key Points

• An inverse relationship between experience and outcome for higher-risk procedures has been repeatedly demonstrated over the past 30 years.

• In the case of percutaneous coronary angioplasty, the minimum volume thresholds involve low numbers of fewer than four cases per week for hospitals and one case per week for physicians.

• The volume standards affect relatively few patients (4% of all patients undergo percutaneous coronary intervention [PCI] at low-volume hospitals and 7% are treated by low-volume physicians), but relatively larger numbers of operators (27% of hospitals and 44% of physicians perform fewer than 200 and 75 cases per year respectively).

• In considering the evidence, studies must be viewed according to representation by low-volume providers, event rates, and regression techniques.

• Supporting evidence and concern for patients compels the medical community to foster experienced interventional operators and facilities to the extent possible.