Age-dependent improvements in survival after hospitalisation with acute myocardial infarction: an analysis of the Myocardial Ischemia National Audit Project (MINAP).

BACKGROUND: recent studies report an age-dependent decline in mortality after acute myocardial infarction (AMI). OBJECTIVE: to investigate age-dependent improvements in survival after hospitalisation with AMI. DESIGN: population-based cohort study using data from the Myocardial Ischaemia National Audit Project. SUBJECTS: a total of 583,466 patients with AMI admitted to 247 hospitals between 1 January 2003 and 31 December 2010. METHODS: six-month relative survival (RS) was calculated from the ratio of observed to expected survival using an age-, sex- and biennial year-matched population from the Office for National Statistics. Risk-adjusted mortality rates (RMAR) were estimated using shared frailty regression. Data were stratified by age group, AMI phenotype [(ST-elevation myocardial infarction, (STEMI) and non-STEMI, (NSTEMI)] and period of admission to hospital. RESULTS: for STEMI, there was an increase in RS for patients aged 65-80 years (84.8 versus 89.2%) and those over 80 years (68.0 versus 71.8%), but not for patients aged 18 to <65 years (96.4 versus 96.9%). For NSTEMI patients aged 18 to <65 years RS was higher, but stable (95.5 versus 96.8%) and improved for patients aged 65-80 years (83.2 versus 88.5%) and patients aged >80 years (68.3% versus 75.5%). Likewise, RMAR improved for patients aged ≥65 years, were stable and higher for patients <65 years. CONCLUSIONS: there were significant improvements in survival after hospitalisation with AMI in the older but not younger patients. The scope for further reductions in mortality is likely to be much greater for older than younger patients with AMI.

Impact of hospital proportion and volume on primary percutaneous coronary intervention performance in England and Wales.

AIMS: To quantify the determinants of primary percutaneous coronary intervention (PCI) performance in England and Wales between 2004 and 2007. METHODS AND RESULTS: All 8653 primary PCI cases admitted to acute hospitals in England and Wales as recorded in the Myocardial Ischaemia National Audit Project (MINAP) 2004-2007. We studied the impact of the volume of primary PCI cases (hospital volume) on door-to-balloon (DTB) times and the proportion of patients treated with primary PCI (hospital proportion) on 30-day mortality and employed regression analysis to identify reasons for DTB time variations with a multilevel component to express hospital variation. The proportion of patients receiving primary PCI increased from 5% in 2004 to 20% in 2007. Median DTB times reduced from 84 min in 2004 to 61 min in 2007. Median DTB times decreased as the number of primary PCI procedures increased. The 30-day all-cause mortality rate for hospitals performing primary PCI on >25% of ST-elevation myocardial infarction patients [5.0%; 95% confidence interval (CI): 3.9-6.1%] was almost double that of hospitals performing primary PCI on more than 75% (2.7%; 95% CI: 2.0-3.5%). Time-of-day, year of admission, sex, and diabetes significantly influenced DTB times. Hospital variation was evident by a hospital-level DTB time standard deviation of 12 min. CONCLUSIONS: There was a large variation in DTB times between the best and worst performing hospitals. Although patient-related factors impacted upon DTB times, the volume and proportion of patients undergoing primary PCI were significantly associated with delay and early mortality-hospitals with the highest proportion of primary PCI had the lowest mortality.

Association between operator volume and mortality in primary percutaneous coronary intervention.

BACKGROUND: There is a paucity of real-world data assessing the association of operator volumes and mortality specific to primary percutaneous coronary intervention (PPCI). METHODS: Demographic, clinical and outcome data for all patients undergoing PPCI in Leeds General Infirmary, UK, between 1 January 2009 and 31 December 2011, and 1 January 2013 and 31 December 2013, were obtained prospectively. Operator volumes were analysed according to annual operator PPCI volume (low volume: 1-54 PPCI per year; intermediate volume: 55-109 PPCI per year; high volume: ≥110 PPCI per year). Cox proportional hazards regression analyses were undertaken to investigate 30-day and 12-month all-cause mortality, adjusting for confounding factors. RESULTS: During this period, 4056 patients underwent PPCI, 3703 (91.3%) of whom were followed up for a minimum of 12 months. PPCI by low-volume operators was associated with significantly higher adjusted 30-day mortality (HR 1.48 (95% CI 1.05 to 2.08); p=0.02) compared with PPCI performed by high-volume operators, with no significant difference in adjusted 12-month mortality (HR 1.26 (95% CI 0.96 to 1.65); p=0.09). Comparisons between low-volume and intermediate-volume operators, and between intermediate and high-volume operators, showed no significant differences in 30-day and 12-month mortality. CONCLUSIONS: Low operator volume is independently associated with higher probability of 30-day mortality compared with high operator volume, suggesting a volume-outcome relationship in PPCI at a threshold higher than current recommendations.

Association of diabetes with increased all-cause mortality following primary percutaneous coronary intervention for ST-segment elevation myocardial infarction in the contemporary era.

BACKGROUND: We investigated the association between diabetes mellitus (DM) and all-cause mortality in a large cohort of consecutive patients treated with primary percutaneous coronary intervention (PPCI) in the contemporary era. METHODS: We conducted a retrospective analysis of a single-centre registry of patients undergoing PPCI for ST-segment elevation myocardial infarction (STEMI) at a large regional PCI centre between 2005 and 2009. All-cause mortality in relation to patient and procedural characteristics was compared between patients with and without DM. RESULTS: Of 2586 patients undergoing PPCI, 310 (12%) had DM. Patients with DM had a higher prevalence of multi-vessel coronary disease (p<0.001) and prior myocardial infarction (p<0.001). Patients with DM were less commonly admitted directly to the interventional centre (p=0.002). Symptom-to-balloon (p<0.001) and door-to-balloon time (p=0.002) were longer in patients with DM. Final infarct-related-artery TIMI-flow grade was lower in patients with DM (p=0.031). All-cause mortality at 30 days (p=0.0025) and 1 year (p<0.0001) was higher in patients with DM. DM was independently associated with increased mortality after multivariate adjustment for potential confounders. CONCLUSIONS: Mortality remains substantially higher in patients with DM following reperfusion for STEMI in comparison with those without diabetes, despite contemporary management with PPCI. Greater co-morbidity, delayed presentation, longer times-to-reperfusion, and less optimal reperfusion may contribute to adverse outcomes.