The outcome of patients with acute myocardial infarction ineligible for thrombolytic therapy. Israeli Thrombolytic Survey Group

Characteristics and outcomes of patients with ST-segment elevation myocardial infarction excluded from the harmonizing outcomes with revascularization and stents in acute myocardial infarction (HORIZONS-AMI) trial

Randomized controlled trials assessing new drugs and devices tend to exclude subjects who are at greatest risk. The Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trial incorporated broader inclusion criteria in an attempt to include a more representative spectrum of patients presenting with ST-segment elevation myocardial infarction (STEMI). To identify the differences between this modern trial and the real world, we analyzed the characteristics and outcomes of patients with STEMI who were screened but not enrolled at a high-volume recruiting center. Of 318 consecutive patients with STEMI who were screened, 200 (62.9%) were randomized, and 118 (37.1%) were excluded. The baseline characteristics and 30-day and 1-year clinical outcomes were compared in the 2 groups. The excluded patients had numerous high-risk features compared to those randomized, including being older (67.0 ± 12.8 vs 63.0 ± 11.4 years, p = 0.004), more often had had a previous MI (34.7% vs 8.0%, p <0.001), Killip class III-IV (27.4% vs 4.0%, p <0.001), and lower hemoglobin (13.4 ± 2.3 vs 14.8 ± 1.5 g/dl, p <0.001). The excluded patients had markedly greater 30-day and 1-year rates of all-cause mortality (17.4% vs 2.0%, p <0.001, and 27.6% vs 2.5%, p <0.001, respectively), major adverse cardiovascular events (death, MI, ischemia-driven target vessel revascularization, and stroke), major bleeding, and net adverse clinical events (major adverse cardiovascular events or major bleeding). On multivariate analysis, Killip class III-IV at presentation, age, left ventricular ejection fraction, and final Thrombolysis In Myocardial Infarction flow grade 3 were independent predictors of outcome. In conclusion, despite the broadened entry criteria of the HORIZONS-AMI trial, 37.1% of all patients presenting with STEMI at a center with a high rate of enrollment were judged to be ineligible and were excluded. The excluded patients had a significantly greater risk profile and markedly increased mortality and adverse events compared to the trial-eligible group.

Primary angioplasty in acute myocardial infarction: Hypothetical estimate of superiority over aspirin or untreated controls

BACKGROUND

Primary percutaneous transluminal coronary angioplasty (PTCA) in the setting of ST-segment-elevation myocardial infarction has been compared with intravenous thrombolysis, but its effects versus no treatment are not known. Knowledge of the effects of PTCA in this setting is useful as a substantial minority of patients do not receive thrombolysis because of contraindications.

METHODS

A hypothetical primary PTCA versus placebo/control odds ratio was computed using a recently described statistical technique that employed the logarithm of the odds ratios of the pooled results of meta-analyses of PTCA versus thrombolysis and thrombolysis versus placebo or controlled trials.

RESULTS

Using data from 30 trials, the synthesized odds ratio for mortality for primary PTCA versus placebo/untreated controls is 0.56 (95% confidence interval [CI]: 0.46 to 0.68; P <0.00001), consistent with a 44% reduction. Primary PTCA and aspirin reduces mortality by 69% versus no aspirin (OR = 0.31; 95% CI: 0.21 to 0.45; P <0.00001). In a high-risk group of otherwise eligible patients with thrombolysis contraindications, the absolute benefit is estimated as 93 per 1000 treated (95% CI: 53 to 132 per 1000 treated). The risk of stroke is reduced with primary PTCA (OR = 0.46; 95% CI: 0.30 to 0.71; P = 0.0004).

CONCLUSION

In this setting, primary PTCA would hypothetically reduce the short-term risk of death by 44%. Despite the use of aggressive antithrombotic regimens, the risk of stroke would also be reduced substantially with primary PTCA.

A randomized trial comparing myocardial salvage achieved by coronary stenting versus balloon angioplasty in patients with acute myocardial infarction considered ineligible for reperfusion therapy

OBJECTIVES

We assessed myocardial salvage achieved by reperfusion with percutaneous coronary interventions (PCI) and compared stenting with balloon angioplasty (PTCA) in patients with acute myocardial infarction (AMI) ineligible for thrombolysis.

BACKGROUND

A substantial proportion of patients with AMI are currently considered ineligible for thrombolysis, and reperfusion treatment is frequently not recommended for them. It is not known whether these patients benefit from PCI.

METHODS

The Stent or PTCA for Occluded Coronary Arteries in Patients with Acute Myocardial Infarction Ineligible for Thrombolysis (STOPAMI-3) trial, a randomized, open-label study, included 611 patients with AMI who were ineligible for thrombolysis (lack of ST-segment elevation on the electrocardiogram, late presentation >12 h after symptom onset, and contraindications to thrombolysis). Patients were randomly assigned to receive either coronary artery stenting (n = 305) or PTCA (n = 306). Scintigraphic myocardial salvage index (proportion of the initial myocardial perfusion defect that was salvaged by reperfusion) was the primary end point of the study.

RESULTS

A considerable myocardial salvage was achieved with both stenting and PTCA. In patients assigned to receive stenting, the median size of the salvage index was 0.54 (25th and 75th percentiles, 0.29 and 0.87), as compared with a median of 0.50 (25th and 75th percentiles, 0.26 and 0.82) in the group assigned to receive PTCA (p = 0.20). Mortality at six months was 8.2% in the group of patients assigned to receive stenting and 9.2% in the group of patients assigned to receive PTCA (p = 0.69).

CONCLUSIONS

Patients with AMI who are currently considered ineligible for thrombolysis by conventional guidelines may greatly benefit from primary PCI. The benefit seems to be comparable when a strategy of stenting is compared with a strategy of PTCA in these patients.

Outcome of patients with post acute myocardial infarction ischemia hospitalized in intensive cardiac care units with and without on-site catheterization laboratories

BACKGROUND

This study addresses the impact of availability of on-site catheterization laboratories on the 1-year survival of patients with post-acute myocardial infarction ischemia (P-AMI-I), a high-risk subgroup of AMI patients.

METHODS

A prospective 5 month national survey was conducted in 1996 in all operating intensive care units (ICCUs) in Israel (N=26) and included 2377 patients. Four hundred and three (17%) had P-AMI-I, 317 of them were admitted to 18 ICCUs with on-site catheterization laboratories (CATH+) and 86 patients to 8 ICCUs without such facilities (CATH-). A retrospective analysis was performed comparing the in-hospital course and 7 day, 1 month and 1 year mortality data of CATH+ vs. CATH- patients.

RESULTS

Patient characteristics in both groups were similar with regard to age, gender AMI location, risk factors, hemodynamic parameters on admission and rate of thrombolytic therapy. Of patients in CATH+, 79% were catheterized before hospital discharge vs. 42% in CATH- (P<0.0001), 45 vs. 15% had PTCA (P<0.0001) and 19 vs. 9% had CABG (P<0.05). At 30 days, patients in CATH+ still had significantly more revascularization procedures (71 vs. 48%, P<0.001). Patients hospitalized in ICCUs with CATH+ and CATH- facilities had similar cardiac mortality rates at 7 days (2.0 vs. 2.3%), 30 days (5.7 vs. 4.7%) and at 1 year (7.6 vs. 7.0%).

CONCLUSIONS

Despite a more invasive strategy used during the index hospitalization of patients with P-AMI-I hospitalized in CATH+ ICCUs, their survival was similar to CATH- patients at 7 days, 30 days and at 1 year follow-up.

Cardiac rehabilitation: socially deprived patients are less likely to attend but patients ineligible for thrombolysis are less likely to be invited

OBJECTIVE

To identify factors associated with the uptake of cardiac rehabilitation following acute myocardial infarction.

DESIGN

Retrospective analysis using multivariate logistic regression modelling.

SETTING

Two large teaching hospitals in Nottingham.

PATIENTS

Cohorts of patients admitted with acute myocardial infarction in 1992 and 1996.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Factors in multivariate analysis found to be associated with attendance at cardiac rehabilitation. Use of secondary prevention in those who were and were not invited and those who did and did not attend cardiac rehabilitation.

RESULTS

58% of all patients were offered cardiac rehabilitation. Attendance rates were 60% in 1992 and 74% in 1996. Invitations were more likely to be offered to younger patients, those who had received thrombolysis, and to patients admitted to one of the two Nottingham hospitals. Use of secondary prevention was only 48% in 1992 but this increased to 80% in 1996. Patients not receiving secondary prevention were less likely to be invited to cardiac rehabilitation. Social deprivation was the only factor significantly associated with poor uptake of cardiac rehabilitation in both years. There was no difference in the use of secondary prevention between those who did and did not attend cardiac rehabilitation.

CONCLUSION

Those invited to attend a cardiac rehabilitation programme are likely to be in a good prognosis group, comprising those who are young and have received thrombolysis. Those at greatest risk, particularly patients from socially deprived areas, seem to be missing out on the potential benefits of cardiac rehabilitation. High risk patients should be specifically targeted to ensure that they are invited to, and encouraged to, attend a programme of cardiac rehabilitation.

Long-term (three-year) prognosis of patients treated with reperfusion or conservatively after acute myocardial infarction. Israeli Thrombolytic Survey Group

OBJECTIVES

This survey sought to assess the frequency of the use of thrombolytic therapy, invasive coronary procedures (ICP) (angiography, percutaneous transluminal coronary angioplasty and coronary artery bypass grafting [CABG]), variables associated with their use, and their impact on early (30-day) and long-term (3-year) mortality after acute myocardial infarction (AMI).

BACKGROUND

Few data are available regarding the implementation in daily practice of the results of clinical trials of treatments for AMI and their impact on early and long-term prognosis in unselected patients after AMI.

METHODS

A prospective community-based national survey was conducted during January-February 1994 in all 25 coronary care units operating in Israel.

RESULTS

Among 999 consecutive patients with an AMI (72% men; mean age 63+/-12 years) acute reperfusion therapy (ART) was used in 455 patients (46%; thrombolysis in 435 patients [44%] and primary angioplasty in 20 [2%]). Its use was independently associated with anterior AMI location and hospitals with on-site angioplasty facilities, whereas advancing age, prior myocardial infarction (MI) and prior angioplasty or CABG were independently associated with its lower use. The three-year mortality of patients treated with ART was lower than in counterpart patients (22.0% vs. 31.4%, p = 0.0008), mainly as the result of 30-day to 3-year outcome (12.4% vs. 21.1%; hazard ratio = 0.73, 95% confidence interval [CI] 0.52 to 1.03). Independent predictors of long-term mortality were: age, heart failure on admission or during the hospitalization, ventricular tachycardia or fibrillation and diabetes. The outcome of patients not treated with ART differed according to the reason for the exclusion, where patients with contraindications experienced the highest three-year (50%) mortality rate. After ART, coronary angiography, angioplasty and CABG were performed in-hospital in 28%, 12% and 5% of patients, respectively. Their use was independently associated with recurrent infarction or ischemia, on-site catheterization or CABG facilities, non-Q-wave AMI and anterior infarct location. In the entire study population, and in patients with a non-Q-wave AMI, performance of ICP was associated with lower 30-day mortality (odds ratio [OR] = 0.53, 95% CI 0.25 to 0.98, and OR = 0.21, 0.03 to 0.84, respectively), but not thereafter.

CONCLUSIONS

This survey demonstrates the extent of implementation in daily practice of ART and ICP and their impact on early and long-term prognosis in an unselected population after AMI.

Relevance of clinical trial results in myocardial infarction to medical practice: comparison of four year outcome in participants of a thrombolytic trial, patients receiving routine thrombolysis, and those deemed ineligible for thrombolysis

OBJECTIVE

To assess the medium to long term outcome of patients ineligible for thrombolysis compared to those enrolled in a clinical trial of thrombolysis and patients receiving non-trial thrombolysis.

DESIGN

Cohort study based on the Nottingham heart attack register.

SETTING

Two district general hospitals serving a defined urban/rural population.

SUBJECTS

All patients admitted with a confirmed acute myocardial infarction during 1992 categorised as either participants of a thrombolytic trial (group A, n = 140), receiving non-trial thrombolysis (group B, n = 329), or deemed ineligible for lytic treatment (group C, n = 431).

MAIN OUTCOME MEASURES

Background characteristics, inhospital treatment, patterns of follow up, referrals to cardiologists, revascularisation rates, and short and long term survival.

RESULTS

Clinical trial recruits were younger by almost 10 years, were less likely to have a previous history of myocardial infarction, and more likely to be in Killip class 1 on admission than those ineligible for thrombolysis. Cardiology follow up was mandatory for all surviving trial participants but 22% of patients in group B and 31% of patients in group C received no follow up, and during four years less than 50% ever saw a cardiologist. Revascularisation was performed in 17.2% of patients in group A, 13.6% of patients in group B, and 7.5% of patients in group C. Cumulative mortality at a median of four years was 24.3% in group A, 36.8% in B, and 59.6% in group C. Adjusting for age, sex, previous myocardial infarction, type of infarction, and Killip class in a logistic regression model the odds ratios (OR) of death at four years for groups B and C were 1.60 (95% confidence intervals (CI) 0.97 to 2.63, p = 0.065) and 2.64 (95% CI 1.61 to 4. 32, p < 0.001), respectively, when compared to group A (OR 1).

CONCLUSIONS

Patients enrolled into thrombolytic trials are at low risk. Patients deemed ineligible for thrombolysis are high risk, receive less surveillance, are less likely to be revascularised or receive trial proven treatments, have a poor long term outcome not entirely explained by increased age or severity of infarction, and deserve further evaluation.

A prospective randomized trial of triage angiography in acute coronary syndromes ineligible for thrombolytic therapy. Results of the medicine versus angiography in thrombolytic exclusion (MATE) trial

OBJECTIVES

The purpose of this study was to determine if early triage angiography with revascularization, if indicated, favorably affects clinical outcomes in patients with suspected acute myocardial infarction who are ineligible for thrombolysis.

BACKGROUND

The majority of patients with acute myocardial infarction and other acute coronary syndromes are considered ineligible for thrombolysis and therefore are not afforded the opportunity for early reperfusion.

METHODS

This multicenter, prospective, randomized trial evaluated in a controlled fashion the outcomes following triage angiography in acute coronary syndromes ineligible for thrombolytic therapy. Eligible patients (n=201) with <24 h of symptoms were randomized to early triage angiography and subsequent therapies based on the angiogram versus conventional medical therapy consisting of aspirin, intravenous heparin, nitroglycerin, beta-blockers, and analgesics.

RESULTS

In the triage angiography group, 109 patients underwent early angiography and 64 (58%) received revascularization, whereas in the conservative group, 54 (60%) subsequently underwent nonprotocol angiography in response to recurrent ischemia and 33 (37%) received revascularization (p=0.004). The mean time to revascularization was 27+/-32 versus 88+/-98 h (p=0.0001) and the primary endpoint of recurrent ischemic events or death occurred in 14 (13%) versus 31 (34%) of the triage angiography and conservative groups, respectively (45% risk reduction, 95% CI 27-59%, p=0.0002). There were no differences between the groups with respect to initial hospital costs or length of stay. Long-term follow-up at a median of 21 months revealed no significant differences in the endpoints of late revascularization, recurrent myocardial infarction, or all-cause mortality.

CONCLUSIONS

Early triage angiography in patients with acute coronary syndromes who are not eligible for thrombolytics reduced the composite of recurrent ischemic events or death and shortened the time to definitive revascularization during the index hospitalization. Despite more frequent early revascularization after triage angiography, we found no long-term benefit in cardiac outcomes compared with conservative medical therapy with revascularization prompted by recurrent ischemia.

Heterogeneity of prognosis in patient subsets treated by primary coronary angioplasty during acute myocardial infarction

Among 377 patients consecutively treated with primary coronary angioplasty for acute myocardial infarction, in-hospital mortality was higher in patients ineligible than in patients eligible for thrombolysis (14.4% vs 7.8%, p <0.05). It remained dismal (75.9%) in patients with cardiogenic shock, but was similar in lytic-eligible patients and in those who were ineligible because of an increased bleeding risk (7.8% vs 7.2%, p = NS), and was zero in patients with nondiagnostic electrocardiograms.