Recurrent ischemia after thrombolysis: importance of associated clinical findings. GUSTO-I Investigators. Global Utilization of Streptokinase and t-PA [tissue-plasminogen activator] for Occluded Coronary Arteries

Dynamic TIMI risk score for STEMI

Background

Although there are multiple methods of risk stratification for ST‐elevation myocardial infarction (STEMI), this study presents a prospectively validated method for reclassification of patients based on in‐hospital events. A dynamic risk score provides an initial risk stratification and reassessment at discharge.

Methods and Results

The dynamic TIMI risk score for STEMI was derived in ExTRACT‐TIMI 25 and validated in TRITON‐TIMI 38. Baseline variables were from the original TIMI risk score for STEMI. New variables were major clinical events occurring during the index hospitalization. Each variable was tested individually in a univariate Cox proportional hazards regression. Variables with P<0.05 were incorporated into a full multivariable Cox model to assess the risk of death at 1 year. Each variable was assigned an integer value based on the odds ratio, and the final score was the sum of these values. The dynamic score included the development of in‐hospital MI, arrhythmia, major bleed, stroke, congestive heart failure, recurrent ischemia, and renal failure. The C‐statistic produced by the dynamic score in the derivation database was 0.76, with a net reclassification improvement (NRI) of 0.33 (P<0.0001) from the inclusion of dynamic events to the original TIMI risk score. In the validation database, the C‐statistic was 0.81, with a NRI of 0.35 (P=0.01).

Conclusions

This score is a prospectively derived, validated means of estimating 1‐year mortality of STEMI at hospital discharge and can serve as a clinically useful tool. By incorporating events during the index hospitalization, it can better define risk and help to guide treatment decisions.

A research method for detecting transient myocardial ischemia in patients with suspected acute coronary syndrome using continuous ST-segment analysis

Each year, an estimated 785,000 Americans will have a new coronary attack, or acute coronary syndrome (ACS). The pathophysiology of ACS involves rupture of an atherosclerotic plaque; hence, treatment is aimed at plaque stabilization in order to prevent cellular death. However, there is considerable debate among clinicians, about which treatment pathway is best: early invasive using percutaneous coronary intervention (PCI/stent) when indicated or a conservative approach (i.e., medication only with PCI/stent if recurrent symptoms occur).

There are three types of ACS: ST elevation myocardial infarction (STEMI), non-ST elevation MI (NSTEMI), and unstable angina (UA). Among the three types, NSTEMI/UA is nearly four times as common as STEMI. Treatment decisions for NSTEMI/UA are based largely on symptoms and resting or exercise electrocardiograms (ECG). However, because of the dynamic and unpredictable nature of the atherosclerotic plaque, these methods often under detect myocardial ischemia because symptoms are unreliable, and/or continuous ECG monitoring was not utilized.

Continuous 12-lead ECG monitoring, which is both inexpensive and non-invasive, can identify transient episodes of myocardial ischemia, a precursor to MI, even when asymptomatic. However, continuous 12-lead ECG monitoring is not usual hospital practice; rather, only two leads are typically monitored. Information obtained with 12-lead ECG monitoring might provide useful information for deciding the best ACS treatment.

Purpose. Therefore, using 12-lead ECG monitoring, the COMPARE Study (electroCardiographic evaluatiOn of ischeMia comParing invAsive to phaRmacological trEatment) was designed to assess the frequency and clinical consequences of transient myocardial ischemia, in patients with NSTEMI/UA treated with either early invasive PCI/stent or those managed conservatively (medications or PCI/stent following recurrent symptoms). The purpose of this manuscript is to describe the methodology used in the COMPARE Study.

Method. Permission to proceed with this study was obtained from the Institutional Review Board of the hospital and the university. Research nurses identify hospitalized patients from the emergency department and telemetry unit with suspected ACS. Once consented, a 12-lead ECG Holter monitor is applied, and remains in place during the patient's entire hospital stay. Patients are also maintained on the routine bedside ECG monitoring system per hospital protocol. Off-line ECG analysis is done using sophisticated software and careful human oversight.

Long-term prognosis of patients with early post-infarction angina

BACKGROUND

Most studies have shown that early post-infarction angina (EPA) implies an unfavorable long-term prognosis among patients with acute myocardial infarction (AMI). However, some studies have failed to establish a link between the occurrence of EPA and increased mortality and recurrent infarction rates.

METHODS AND RESULTS

In order to evaluate a long-term prognosis in patients with EPA, we assessed the 5-year prognosis of 80 patients with AMI by the presence or absence of EPA. During the 5-year follow up, the occurrence of death, cardiac death, recurrent infarction, unstable angina, heart failure, revascularization and cardiac events were recorded. A cardiac event was defined as an occurrence of any of the following events: cardiac death, recurrent infarction, unstable angina, heart failure and revascularization. Survival analysis showed no differences between patients with and without EPA in the probability of death (p=NS), cardiac death (p=NS), recurrent myocardial infarction (p=NS) and unstable angina (p=NS). Patients with EPA had a higher probability of developing cardiac events (p=0.0285) and undergoing revascularization procedures (p=0.0188).

CONCLUSIONS

EPA increases the risk of patients developing cardiac events and undergoing revascularization procedures, and thereby implies a poor long-term prognosis for patients with AMI.

Prediction of infarction-related artery occlusion and multivessel disease in postinfarction angina

CONDENSED ABSTRACT

To investigate the predictive value of clinical data for infarction-related artery (IRA) occlusion and multivessel coronary disease in postinfarction angina (PIA), we studied 181 consecutive patients presenting PIA following a first uncomplicated ST elevation AMI. Multivariate analysis showed ECG changes during PIA and the absence of thrombolytic therapy as independent predictors of IRA occlusion. Independent clinical predictors of multivessel coronary disease were age, previous history of angina and the number of cardiovascular risk factors. We conclude that reversible ECG changes during PIA correlated to IRA occlusion but failed to predict a multivessel coronary disease.

AIM

To identify clinical variables predictive of infarction-related artery (IRA) occlusion and multivessel coronary disease in patients with postinfarction angina pectoris (PIA) after a first uncomplicated acute myocardial infarction (AMI).

METHODS

We studied 181 consecutive patients with PIA following a first uncomplicated AMI. Clinical variables included cardiovascular risk factors, clinical history of angina before the event of inclusion, use of thrombolytic therapy in the previous AMI, ST-T changes during PIA, time to onset, number of episodes and delay to angiography after PIA. Angiographic variables were IRA TIMI flow, number of diseased vessels and ventricular function.

RESULTS

The IRA was occluded in 67 patients with PIA (37.0%). Reversible ECG changes during PIA were detected in 121 patients (67.0%): 79 cases (43.6%) with ST/T elevation and 42 cases (23.2%) with ST/T depression. Multivariate logistic regression analysis showed ECG changes during PIA (OR 3.12 CI 95% 1.48-6.54, p<0.01) and the absence of thrombolytic therapy (OR 2.21 95% CI 1.11-4.43, p<0.05) as independent predictors of IRA occlusion. We found multivessel coronary disease in 89 patients (49.2%) without any correlation to ECG changes during PIA. Independent clinical predictors of multivessel coronary disease were age (OR 1.03 95% CI 1.01-1.06, p<0.05), previous history of angina (OR 2.37 95% CI 1.06-5.28, p<0.05) and the number of cardiovascular risk factors (OR 1.37 95% CI 0.97-1.92, p=0.07).

CONCLUSIONS

ECG changes during PIA was correlated to IRA occlusion in spite of previous thrombolytic therapy but failed to predict a multivessel coronary disease in our patients.

ST-deviation patterns in recurrent myocardial infarctions

Myocardial infarction (MI) may be classified as ST-elevation MI (STEMI) or non-STEMI (NSTEMI). We used the term "recurrent MI" (RMI) to denote repeat MI episodes in a particular patient in which a different coronary site is responsible for each episode. We investigated whether the type of RMI is more likely to be of the same type as the index MI or whether patients may have the 2 types of MI at random. The analysis included 305 patients who had >or=2 MI episodes. Acute MIs were classified as STEMI or NSTEMI. We attempted to include only MIs of native vessels, without the presence of extracardiac conditions that intensify myocardial ischemia. Most patients (76%) had repeat episodes of the same MI type, i.e., STEMI or NSTEMI. Recurrent STEMI occurred in 44% of patients, recurrent NSTEMI in 32%, and STEMI and NSTEMI in 24%. Thus, most patients with RMI episodes will have STEMIs or NSTEMIs but not the 2 types, suggesting a predilection of some patients to repeat episodes of occlusive thrombi and others to repeat episodes of nonocclusive thrombi.

[Prognostic value of early post-infarction angina in elderly patients]

Although numerous studies have shown that early post-infarction angina was a predictor of poor prognosis in patients with acute myocardial infarction, not a single study has considered this issue in the elderly. The goal of this study, based on a five-year follow-up of elderly patients with acute myocardial infarction, was to determine whether early post-infarction angina in the elderly had any influence on mortality and the incidence of additional coronary events. The study population consisted of 51 patients, aged 60 years or more, with acute myocardial infarction. Early post-infarction angina occurred in 31 subjects (Group 1), while it did not in 20 subjects (Group 2). Patients were monitored for five years and the incidences of death and new coronary events were recorded. A survival analysis was carried out using the Kaplan-Meier method. The survival analysis showed no difference between the observed groups concerning the following probabilities: death (p = 0.9459), cardiac death (p = 0.8253), myocardial reinfarction (p = 0.7405), new coronary events (p = 0.1708), unstable angina (p = 0.1788), myocardial revascularisation (p = 0.0691), and heart failure (p = 0.7047). In contrast to the younger population, where numerous studies have confirmed the link between early post-infarction angina and poor long-term prognosis, such findings could not be replicated in this study of the elderly population.

Combined Angioplasty and Pharmacological Intervention Versus Thrombolysis Alone in Acute Myocardial Infarction (CAPITAL AMI Study)

OBJECTIVES

We compared a strategy of tenecteplase (TNK)-facilitated angioplasty with one of TNK alone in patients presenting with high-risk ST-segment elevation myocardial infarction (STEMI).

BACKGROUND

Previous trials show that thrombolysis followed by immediate angioplasty for the treatment of STEMI does not improve ischemic outcomes compared with thrombolysis alone and is associated with excessive bleeding complications. Since the publication of these trials, however, significant pharmacological and technological advances have occurred.

METHODS

We randomized 170 patients with high-risk STEMI to treatment with TNK alone (84 patients) or TNK-facilitated angioplasty (86 patients). The primary end point was a composite of death, reinfarction, recurrent unstable ischemia, or stroke at six months.

RESULTS

At six months, the incidence of the primary end point was 24.4% in the TNK-alone group versus 11.6% in the TNK-facilitated angioplasty group (p = 0.04). This difference was driven by a reduction in the rate of recurrent unstable ischemia (20.7% vs. 8.1%, p = 0.03). There was a trend toward a lower reinfarction rate with TNK-facilitated angioplasty (14.6% vs. 5.8%, p = 0.07). No significant differences were observed in the rates of death or stroke. Major bleeding was observed in 7.1% of the TNK-alone group and in 8.1% of the TNK-facilitated angioplasty group (p = 1.00).

CONCLUSIONS

In patients presenting with high-risk STEMI, TNK plus immediate angioplasty reduced the risk of recurrent ischemic events compared with TNK alone and was not associated with an increase in major bleeding complications.

Association of Transient Myocardial Ischemia With Adverse In-Hospital Outcomes for Angina Patients Treated in a Telemetry Unit or a Coronary Care Unit

• Background Little is known about the frequency or consequences of transient myocardial ischemia in patients admitted to a telemetry unit for treatment of angina.

• Objectives To compare the rate of transient myocardial ischemia in a group of patients with angina treated in a telemetry unit with the rate in a similar group treated in a coronary care unit and to determine if transient myocardial ischemia is associated with adverse in-hospital outcomes.

• Methods Continuous 12-lead electrocardiography was used to monitor changes in the ST segment in 186 patients in the coronary care unit (1994–1996) and 186 patients in the telemetry unit (1997–2000). Transient myocardial ischemia was defined as a change from baseline of 100 μV or more in the ST segment in 1 or more leads lasting 60 seconds or longer.

• Results The rate of transient myocardial ischemia was 15% for patients in the telemetry unit and 19% for patients in the coronary care unit. Regardless of hospital unit, patients with transient myocardial ischemia were more likely than those without this complication to experience death or acute myocardial infarction after hospital admission. Most patients did not experience signs or symptoms during transient myocardial ischemia: 71% of patients in the telemetry unit versus 58% of patients in the coronary care unit (P = .28).

• Conclusions Transient myocardial ischemia is common among patients with angina treated in a telemetry unit. ST-segment monitoring may be useful for detecting patients with ischemia who may benefit from more aggressive therapies aimed at abolishing ongoing ischemia.

Recurrent ischemia after thrombolysis for acute myocardial infarction

BACKGROUND

Reliable predictors have yet to be found for recurrent ischemia after thrombolysis for acute myocardial infarction (AMI), nor do we know whether early angiography can herald recurrent ischemia. This study sought to investigate the relationship between recurrent ischemia and cardiac procedures after thrombolysis for AMI.

METHODS

The Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO-I) trial prospectively studied recurrent ischemia, which was defined as the presence of angina and changes in hemodynamics or the electrocardiogram. Cox regression analysis was used to identify predictors of recurrent ischemia. Other variables examined included time to coronary angiography and revascularization.

RESULTS

Of 21,772 US GUSTO-I patients, 6313 (29%) had recurrent ischemia before discharge. Women (hazard ratio [HR] 1.25, 95% confidence interval [CI] 1.17-1.33) and patients with hypercholesterolemia (HR 1.14, 95% CI 1.07-1.22) or prior angina (HR 1.40, 95% CI 1.32-1.49) had a higher likelihood of recurrent ischemia. Current smoking and hours to thrombolysis were inversely related to recurrent ischemia (HR 0.86, 95% CI 0.81-0.92, HR 0.97, 95% CI 0.95- 0.99, respectively). Patients who underwent angiography before recurrent ischemia had a marginally increased risk of ischemia within 12 hours after angiography (HR 1.2, 95% CI 1.1-1.4); ultimately, they had a considerably lower risk 1 week after angiography than did patients without angiography (HR 0.57, 95% CI 0.45-0.72).

CONCLUSIONS

Female sex, hypercholesterolemia, prior angina, and nonsmoking status weakly predict recurrent ischemia. Early coronary angiography reduces recurrent ischemia, probably because high-risk patients are identified and revascularized.

[In-hospital evolution and current prognosis of unstable angina]

INTRODUCTION AND PROGNOSIS

The prognosis of patients with unstable angina has improved in recent years resulting in a progressive reduction in hospital stay and treatment. The aim of this study was to know the current prognosis of patients with unstable angina in a non-selected population followed for up to 3 months.

PATIENTS AND METHODS

478 consecutive patients with unstable angina were studied. They were treated following a strict protocol and a management policy guided by symptoms and the results of an exercise test or a pharmacological stress test performed before hospital discharge.

RESULTS

The mean age was 66 +/- 11 years with 30% being females. Thirty-five percent had a prior history of myocardial infarction, 61% presented ischemic changes on the admission ECG, and 16% had elevation of the CK-MB plasma levels. An echocardiogram was performed in 80% of the patients, a stress test in 62%, coronary angiography in 51%, and a revascularization procedure in 27% of the patients. During hospitalization, the incidence of mortality or myocardial infarction, refractory angina or ischemic complications was of 3.6%, 11% and 13%, respectively. After hospital discharge and during a 3-month follow-up, the incidence of these complications was of 3.3%, 9% and 10% (NS compared to the in-hospital period). Overall, from the time of hospital admission to the 3-month follow-up, 4.2% of the patients died, 7% died or had an infarction, 20% had refractory angina, and 26% had some ischemic complication.

CONCLUSION

The in-hospital prognosis of unstable angina is currently good. However, patients discharged from hospital after stabilization, present an important number of ischemic complications during the following 3 months, similar to that presented by all patients during the acute phase.

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.

[The clinical management guidelines of the Sociedad Española de Cardiología in acute myocardial infarct]

In the recent years, new possibilities have emerged in the diagnosis and management of acute myocardial infarction with ST segment elevation and its complications. Moreover, a deep transformation has taken place in the health care system organization, particularly in aspects related to care of patients presenting non-traumatic chest pain, both in pre-hospital and hospital areas. All these issues warrant a consensus document in Spain dealing with the role that these important changes should play in the whole management of myocardial infarction patients. This document revises and updates all the main clinical issues of acute myocardial infarction patients from the moment they contact with the health care system outside the hospital until they return home, after staying at the coronary care unit and the general hospitalization ward. All those aspects are considered not only in the uncomplicated myocardial infarction but also in the complicated one. This review also includes a set of recommendations on structural and organisational aspects, mainly referred to the prehospital and emergency levels.