Baseline characteristics by annual hospital volume
| Lower volume (<200 procedures/year) (n=2835) | Higher volume (≥200 procedures/year) (n=11 602) | |
| Demographics | ||
| Female | 611 (22.8%) | 2329 (21.1%) |
| Age | 67.4±11.0 | 67.8±11.1 |
| BMI | 24.4±3.6 | 24.1±3.6 |
| Medical history | ||
| Diabetes (%) | 1067 (37.6%) | 4658 (40.1%) |
| Hypertension (%) | 2016 (71.1%) | 8202 (70.7%) |
| Smoker (%) | 1021 (36.0%) | 3471 (29.9%) |
| Dyslipidaemia (%) | 1701 (60.0%) | 7328 (63.2%) |
| Chronic renal failure (%) | 976 (39.6%) | 4621 (42.5%) |
| Dialysis (%) | 116 (4.1%) | 551 (4.7%) |
| Chronic lung disease (%) | 71 (2.5%) | 355 (3.1%) |
| Peripheral vascular disease (%) | 146 (5.1%) | 1059 (9.1%) |
| Previous heart failure (%) | 211 (7.4%) | 1029 (8.9%) |
| History of MI (%) | 645 (22.8%) | 2637 (22.7%) |
| Cerebral artery disease (%) | 186 (6.6%) | 1017 (8.8%) |
| History of PCI (%) | 988 (34.9%) | 4243 (36.6%) |
| Clinical presentation | ||
| STEMI (%) | 630 (22.2%) | 2147 (18.5%) |
| NSTEMI (%) | 201 (7.1%) | 818 (7.1%) |
| Unstable angina (%) | 485 (17.1%) | 2059 (17.7%) |
| Heart failure symptom (%) | 348 (12.3%) | 266 (10.9%) |
Values are presented as n (%) or mean±SD, as indicated.
BMI, body mass index; MI, myocardial infarction; NSTEMI, non-ST-elevation myocardial infarction; PCI, percutaneous coronary intervention; STEMI, ST-elevation myocardial infarction.