Summary

This article presents a registry analysis demonstrating that ST-segment elevation myocardial infarction patients admitted to hospitals with a cath lab are treated with significantly higher rates of reperfusion and guideline-recommended adjunctive therapies and that this treatment is associated with a lower 1-year mortality.

  • myocardial infarction

Alexandros Skarlos, MD, Klinikum Ludwigshafen, Germany, presented a registry analysis demonstrating that STEMI patients admitted to hospitals with a cath lab are treated with significantly higher rates of reperfusion and guideline-recommended adjunctive therapies and that this treatment is associated with a lower 1-year mortality.

The results are based on an analysis of data from the ACOS registry for 8,303 STEMI patients of whom 6,351 (76.5%) were initially admitted to a hospital with a cath lab and 1,952 (23.5%) to a hospital without such a facility.

During the first 24 hours, reperfusion therapy was significantly more common in hospitals equipped with a cath lab (75.6%) vs those without (54%; p<0.0001). A comparison of other treatments and in-hospital and 1-year mortality rates are shown in Table 1.

Table 1.

Treatment and Mortality Differences.

Most therapy guidelines are based on clinical trial results. However, many patients seen in clinical practice are not represented in clinical trials. Oliver Koeth, MD, Klinikum Ludwigshafen, Germany, presented results of a registry designed to assess whether the patients typically excluded from clinical trials would benefit from guideline adherence.

Data for 36,247 STEMI patients from the MITRA (Maximal Individual Therapy of Acute Myocardial Infarction) PLUS registry were analyzed. Patients were assigned to two groups: those who failed to meet the typical inclusion criteria for most clinical trials (n=16,621) and those who met the criteria (n=19,626). Excluded patients were further assigned to subgroups based on common clinical trial exclusion criteria: age ≥75 years (n=9,360), pre-hospital delay >12 hours (n=5,427), pre-hospital CPR (n=1,719), cardiogenic shock (n=1,192), creatinine >2 mg/dL; (n=1,149), previous stroke/TIA (n=893), and oral anticoagulation with INR >2 (n=198).

Patients often excluded from clinical trials tended to be older, were more likely to be women, and more frequently had existing comorbidities (eg, hypertension, diabetes). These patients received significantly less adjunctive therapy (eg, aspirin, clopidogrel, beta-blockers, ACE-inhibitors, and statins) within 48 hours (each p<0.0001) compared to patients who satisfied typical trial criteria. The rate of reperfusion for excluded patients (42%) was also significantly lower than for included patients (73%; p<0.0001), and was particularly low among patients with a pre-hospital delay >12 hours (30%), those with renal failure (34%) and those aged >75 years or with prior stroke (both 38%).

Overall, hospital mortality was significantly higher in excluded (22%) vs included patients (6%; p<0.0001). However, when data were analyzed based on whether patients had received reperfusion therapy, hospital mortality for patients who received reperfusion therapy was significantly improved in all groups, except those with renal insufficiency (Table 2).

Table 2.

Hospital Mortality Within Subgroup.

These results suggest that adherence to guideline therapy, particularly, early reperfusion therapy, may significantly reduce hospital mortality in STEMI patients with characteristics that would usually exclude them from randomized clinical trials.

In clinical practice adherence to guideline-recommended therapies results in improved outcome in STEMI patients, even in those who are not representative of patients enrolled in the randomized clinical trials from which those guidelines are derived.

Important limitations of these registry analyses include the lack of randomization and the difficulty in fully adjusting for differences in patient characteristics and other clinical issues (eg, patient preference) that may have impacted on the care delivered and clinical outcomes.

View Summary