A coordinated system of care for patients with ST-segment elevation myocardial infarctions that includes prehospital administration of reduced-dose fibrinolytic agents coupled with urgent percutaneous coronary intervention (PCI), termed FAST-PCI, has been shown to be at least as effective as primary PCI (PPCI) alone. However, this reduced-dose fibrinolytic strategy could be associated with increased bleeding risk, especially in elderly patients. The purpose of this study was to examine 30-day outcomes in patients aged ≥75 years with ST-segment elevation myocardial infarctions treated with either strategy. Data from 120 patients aged ≥75 years treated with FAST-PCI were compared with those of 94 patients aged ≥75 years treated with PPCI. The primary comparator was mortality at 30 days. Stroke, reinfarction, and major bleeding were also compared. The groups were well matched for age, cardiac risk factors, and ischemic times. At 30 days, mortality was lower with FAST-PCI than with PPCI (4.2% vs 18.1%, p <0.01). Rates of stroke, reinfarction, and major bleeding (4% vs 2%) were similar in the 2 groups. The FAST-PCI cohort had lower rates of cardiogenic shock on hospital arrival (15% vs 26%, p = 0.05) and completely occluded infarct arteries (Thrombolysis In Myocardial Infarction [TIMI] grade 0 flow, 35% vs 61%, p <0.01). In conclusion, for patients aged ≥75 years with ST-segment elevation myocardial infarctions, a FAST-PCI strategy in a coordinated system of care was associated with reduced 30-day mortality, earlier infarct artery patency, and lower incidence of cardiogenic shock at arrival compared with PPCI, without apparent bleeding, stroke, or reinfarction penalties.
Extensive investigations of treatment strategies for patients with ST-segment elevation myocardial infarctions (STEMIs) have led to many improvements in care. Yet optimal treatment strategies for patients aged ≥75 years with STEMIs are much less clear, and many knowledge gaps remain. Age ≥75 years is an independent predictor of 30-day mortality in STEMI. Although this higher mortality risk generally would dictate more aggressive treatments, recent data have shown, for example, that <1/2 of patients aged ≥80 years with STEMIs are treated with any reperfusion therapies at all.
Our institution for a number of years has used a strategy of field evaluation for STEMI using 12-lead electrocardiograms obtained on the scene by emergency medical service (EMS) personnel and transmitted for overread by emergency center physicians. Eligible patients with STEMIs receive prehospital, reduced-dose fibrinolytic agents along with aspirin, clopidogrel, and heparin and are transported to our STEMI center for urgent percutaneous coronary intervention (PCI). This is termed the FAST-PCI strategy. Patients with STEMIs evaluated by EMS units not equipped with fibrinolytic kits, and those who are not eligible for fibrinolysis, receive aspirin, clopidogrel, and heparin followed by transport for urgent PCI (the primary PCI [PPCI] strategy). The purpose of this retrospective study was to examine differences in outcomes for patients aged ≥75 years treated in this coordinated STEMI system of care according to FAST-PCI or PPCI strategy.
Methods
The prehospital evaluation and treatment protocol our institution has used for >7 years has been described previously. Briefly, there is a field evaluation for STEMI using 12-lead electrocardiograms obtained and transmitted by EMS personnel, with overread by emergency department physicians. Eligible patients with STEMIs are given reduced-dose reteplase (10 U intravenously), aspirin (325 mg orally), clopidogrel (600 mg orally), and heparin (60 U/kg, up to 4,000 U intravenously). Patients with STEMIs who are not eligible for fibrinolysis receive aspirin, clopidogrel, and heparin at the same dosages. Glycoprotein IIb/IIIa inhibitors are used according to local practices or at the discretion of the treating physician.
From March 2006 to February 2013, 1,303 patients with STEMIs were treated at our institution. Of these, 214 (16.4%) were ≥75 years of age and formed the basis of this study. In late 2009, the manufacturer suspended delivery of reteplase, causing our institution to interrupt the FAST-PCI strategy and continue from that point with a completely PPCI protocol for all patients with STEMIs. Patients with STEMIs are still identified in the field, either at the scene or in local referral hospitals. Adjunctive agents including aspirin, clopidogrel, and heparin are still administered and patient transport is initiated, all in a similar manner as when the FAST-PCI and PPCI protocols were in place. Urgent PCI upon hospital arrival also is performed in a similar manner and by the same operators as before.
In the subset of 214 patients aged ≥75 years, the FAST-PCI strategy was used in 120 (56%) and PPCI in 94 (44%). For this retrospective cohort study, we analyzed demographics, clinical features, laboratory data, angiographic data, and outcomes of the 2 strategies. Ischemic time was defined as the time from pain onset to first device activation (first balloon inflation or thrombus aspiration). The primary end point comparison was 30-day mortality. Secondary end points included stroke, reinfarction, and major bleeding. A composite end point of mortality, stroke, reinfarction, or major bleeding was also analyzed. Stroke was defined as the development of new neurologic deficit not present on initial screening examination, neurologist diagnosis of stroke, or new intracranial bleeding diagnosed by computed tomography or magnetic resonance imaging. Reinfarction was defined as new significant Q waves in 2 contiguous leads different from the initial STEMI, reelevation of creatine kinase-MB to normal or higher (or by another 50%, if already normal or higher), and reelevation of creatine kinase-MB to >3 or >5 times the upper limit of normal after angioplasty or surgery, respectively. Major bleeding was defined as bleeding resulting in hemodynamic instability requiring intervention and assessed using Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO) trial criteria. Patients were followed up for events after hospital discharge by telephone call, outpatient visit, or both at 30 days after the index STEMI.
Categorical variables are expressed as numbers and percentages of patients, while continuous variables are expressed as medians and interquartile ranges. Differences were assessed for significance using chi-square tests for categorical variables and Kruskal-Wallis tests for continuous variables. A p value ≤0.05 was considered significant.
Results
Table 1 lists demographics, clinical features, laboratory data, and angiographic data of the 214 patients with STEMIs treated with the FAST-PCI and PPCI strategies. The groups were comparable, except for cardiogenic shock present on admission (hospital arrival) and Thrombolysis In Myocardial Infarction (TIMI) grade 0 flow on initial angiography before PCI. Glycoprotein IIb/IIIa inhibitor use was equivalent in the 2 groups. The 2 groups had similar rates of left anterior descending coronary artery culprit vessel, as well as 3-vessel coronary artery disease. Door-to-balloon time and ischemic time were comparable between the 2 groups.
| Variable | FAST-PCI (n = 120) | PPCI (n = 94) | p Value |
|---|---|---|---|
| Age (yrs) | 78 (76–79) | 77 (76–79) | 0.92 |
| Men | 65 (54%) | 52 (55%) | 0.87 |
| Previous PCI | 26 (22%) | 21 (22%) | 0.91 |
| Previous myocardial infarction | 20 (17%) | 15 (16%) | 0.89 |
| Previous coronary bypass | 8 (7%) | 6 (6%) | 0.93 |
| Hypertension | 90 (75%) | 74 (79%) | 0.52 |
| Smoker | 70 (58%) | 53 (56%) | 0.77 |
| Hyperlipidemia | 70 (58%) | 57 (61%) | 0.73 |
| Diabetes mellitus | 40 (33%) | 36 (38%) | 0.45 |
| Shock on admission | 18 (15%) | 24 (26%) | 0.05 |
| Ischemic time (minutes) | 151 (117–185) | 165 (100–195) | 0.70 |
| Door-to-balloon time (minutes) | 44 (39–51) | 45 (40–57) | 0.06 |
| TIMI grade 0 flow at presentation | 42 (35%) | 57 (61%) | <0.01 |
| 3-vessel coronary artery disease | 32 (27%) | 26 (28%) | 0.87 |
| Left anterior descending coronary artery culprit vessel | 63 (53%) | 56 (60%) | 0.30 |
| Glycoprotein IIb/IIIa inhibitors used | 32 (27%) | 25 (27%) | 0.99 |
| Baseline creatinine (mg/dl) | 1.1 (0.9–1.6) | 0.9 (0.8–1.5) | 0.09 |
| Peak creatine kinase (IU/L) | 978 (348–2,599) | 1,380 (718–2,767) | 0.24 |
Table 2 and Figure 1 display outcomes in the FAST-PCI and PPCI groups. FAST-PCI patients had a 30-day mortality rate approximately 1/4 that of PPCI patients (4.2% vs 18.1%, p <0.01). Secondary end points (stroke, reinfarction, and major bleeding) individually were not significantly different between the 2 groups. There were 5 bleeding events in 120 FAST-PCI patients and 2 in 94 PPCI patients. The composite end point of mortality, stroke, reinfarction, or major bleeding was lower in the FAST-PCI than in the PPCI cohort (11.7% vs 22.3%, p = 0.04). Most of the outcome events in the PPCI cohort were deaths, whereas in the FAST-PCI cohort, events were equally distributed among deaths, strokes, and major bleeding. Of 3 strokes in the PPCI cohort, 2 appeared to be cardioembolic and related to atrial fibrillation; 1 of these patients underwent hemorrhagic conversion. The other stroke appeared to be ischemic. Of 6 strokes in the FAST-PCI cohort, 3 appeared to be cardioembolic and related to atrial fibrillation, and 1 of these patients underwent hemorrhagic conversion. Two of the strokes were ischemic. The final stroke in this cohort occurred in the setting of extremely high blood pressure after PCI, and it was associated with hemorrhagic conversion. Finally, FAST-PCI patients had a slightly shorter length of hospitalization compared with PPCI patients.
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
