Eligibility for reperfusion therapy and outcome in elderly patients with acute myocardial infarction

Practice variation and missed opportunities for reperfusion in ST-segment-elevation myocardial infarction: findings from the Global Registry of Acute Coronary Events (GRACE)

BACKGROUND

The benefits of reperfusion therapy for patients with acute coronary syndromes have been established, but there is much variation in the type of reperfusion given and decisions about which patients are eligible. This study assessed current practices in relation to reperfusion therapy of ST-segment-elevation myocardial infarction from data collected in the multinational, prospective Global Registry of Acute Coronary Events.

METHODS

94 hospitals in 14 countries are recruiting patients for the registry. Hospitals are organised into population-based clusters that reflect the population characteristics of the region. Information about patients' demographic characteristics, presenting symptoms, medical history, time between symptom onset and presentation, and clinical and electrocardiographic features is recorded in a standard case record.

FINDINGS

Of the 9251 patients enrolled, 1763 presented within 12 h of symptom onset with ST-segment-elevation myocardial infarction. Of these, 30% did not receive reperfusion therapy. Elderly patients (75 years and older), those presenting without chest pain, and those with a history of diabetes, congestive heart failure, myocardial infarction, or coronary bypass surgery were less likely to receive reperfusion therapy. The rate of primary percutaneous coronary intervention was highest in the USA and lowest in Australia, New Zealand, and Canada. The rate at sites with a catheterisation laboratory was 19% compared with zero at sites without this facility.

INTERPRETATION

A substantial proportion of patients who are eligible for reperfusion therapy still do not receive this treatment. These typically high-risk patients can be identified in advance, and reasons for the underuse of these beneficial treatments need to be clarified.

Primary angioplasty for acute myocardial infarction in the elderly

Elderly patients with acute myocardial infarction present a formidable therapeutic challenge. Although there appears to be a survival benefit from thrombolytic therapy for the eligible elderly patient, persistent concerns regarding the risk of intracranial hemorrhage impedes utilization in this age group. Primary or direct angioplasty of the infarct artery has been proven to be an effective modality for reperfusion. Randomized comparisons suggest an advantage over thrombolysis in terms of achieving superior patency and mitigating recurrent ischemic events. Primary angioplasty expands the reperfusion population by including many patients ineligible for thrombolysis and is more effective for treating patients at high risk, such as those with cardiogenic shock. Acute angiography accumulates important prognostic and decision-facilitating information. The benefits of primary angioplasty are more impressive for the aging patient. The survival gain and reduction in intracranial hemorrhage may combine to magnify the advantages of performing angioplasty on patients in this group. Emerging evidence concerning the aging population validates continued examination of this invasive reperfusion approach.

Can we provide reperfusion therapy to all unselected patients admitted with acute myocardial infarction?

OBJECTIVES

This study sought to assess the maximal rate of acute Thrombolysis in Myocardial Infarction (TIMI) grade 3 patency that can be achieved in unselected patients.

BACKGROUND

Early and complete (TIMI grade 3 flow) reperfusion is an important therapeutic goal during acute myocardial infarction. However, thrombolysis, although widely used, is often contraindicated or ineffective. The selective use of primary and rescue percutaneous transluminal coronary angioplasty (PTCA) may increase the number of patients receiving reperfusion therapy.

METHODS

A cohort of 500 consecutive unselected patients with acute myocardial infarction were prospectively treated using a patency-oriented scheme: Thrombolysis-eligible patients received thrombolysis (n = 257) and underwent 90-min angiography to detect persistent occlusion for treatment with rescue PTCA. Emergency PTCA (n = 193) was attempted in patients with contraindications to thrombolysis, cardiogenic shock or uncertain diagnosis and in a subset of patients admitted under "ideal conditions." A small group of patients (n = 38) underwent acute angiography without PTCA. Conventional medical therapy was used in 12 patients with contraindications to both thrombolysis and PTCA.

RESULTS

Ninety-eight percent of patients received reperfusion therapy (thrombolysis, PTCA or acute angiography), and angiographically proven early TIMI grade 3 patency was achieved in 78%. Among patients with TIMI grade 3 patency, thrombolysis alone was the strategy used in 37%, emergency PTCA in 40% and rescue PTCA after failed thrombolysis in 15%; spontaneous patency occurred in 8%.

CONCLUSIONS

Reperfusion therapy can be provided to nearly every patient (98%) with acute myocardial infarction. Rescue and direct PTCA provided effective early reperfusion to patients in whom thrombolysis failed or was excluded.