Influence of hospital volume on outcomes for patients with heart failure: Evidence from a Canadian national cohort study.

Although the Get with the Guidelines-Heart Failure (GWTG-HF) group recently reported no association between hospital volume and 30-day outcomes in their registry, GWTG-HF hospitals are self-selected and tend to be higher-volume hospitals with active quality improvement departments. Thus, we explored the volume-outcome relationship for HF in an unselected population-based cohort of 241,533 adults admitted with HF as the most responsible diagnosis to any of 591 acute care institutions in Canada-none participate in GWTG-HF. We found inverse associations between volume and in-patient mortality (11.3% in low-volume hospitals compared to 9.0% in high-volume hospitals, adjusted odds ratio 0.90 [0.80-1.00]) and 30-day readmission rates (19.3% in low-volume hospitals versus 17.3% in high-volume hospitals, adjusted odds ratio 0.91 [0.85-0.97]).