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Byline: Rephael Mohr, Yaron Moshkovitch, Itzhak Shapira, Gabriel Amir, Hanoch Hod, Jacob Gurevitch Abstract: Objective: Between January 1992 and December 1994, 57 patients having an acute myocardial infarction with coronary anatomy suitable for coronary artery bypass grafting without cardiopulmonary bypass underwent this procedure within 1 week of the infarction. We describe the surgical results of these high-risk patients. Methods: The study population included 43 male patients (75%) and 14 female patients (25%) whose mean age was 58.5 [+ or -] 10.4 years. Thirty-two patients (56%) underwent emergency bypass grafting within 48 hours of an acute myocardial infarction, 4 of them (12.5%) as a bailout procedure after complicated percutaneous transluminal coronary angioplasty. Of these 32 patients, 7 patients (22%) were in cardiogenic shock, and 10 patients (31%) required preoperative intra-aortic balloon pump. Twenty-five patients (44%) underwent coronary bypass grafting 2 to 7 days after an acute myocardial infarction. The mean number of grafts per patient was 1.8 (range, 1-4), and the internal thoracic artery was used in 47 patients (82%). Only 7 patients (12%) received grafts to a circumflex marginal branch. Results: Operative mortality was 1.7% (1 patient), and the mean postoperative hospital stay was 6.8 [+ or -] 3 days. One- and 5-year actuarial survivals were 94.7% and 82.3%, respectively. Angina returned in 7 patients (12%), 1 of whom underwent reoperation. Multivariate analysis revealed renal failure and preoperative cardiogenic shock to be independent predictors of overall mortality. Old myocardial infarction and operation within the first 48 hours were independent predictors of overall unfavorable outcome events. Conclusions: These results suggest that coronary artery bypass grafting without cardiopulmonary bypass is a relatively low-risk procedure for patients having an infarction with coronary anatomy suitable for this technique. (J Thorac Cardiovasc Surg 1999;118:50-6) Author Affiliation: From The Department of Thoracic and Cardiovascular Surgery, Tel Aviv Sourasky Medical Center, Tel Aviv,.sup.a and The Heart Institute, The Chaim Sheba Medical Center, Tel Hashomer,.sup.b affiliated to the Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel Article History: Received 17 September 1998; Revised 4 November 1998; Revised 3 March 1999; Accepted 3 March 1999 Article Note: (footnote) [star] Address for reprints: Rephael Mohr, MD, The Department of Thoracic and Cardiovascular Surgery, Tel Aviv Sourasky Medical Center, 6 Weizman St, Tel Aviv 64239, Israel., [star][star] 12/1/98437

Background: Patients with a history of stroke presenting with acute myocardial infarction (MI) are often excluded from thrombolytic therapy owing to fear of intracranial hemorrhage. Few data, however, are available on the risks vs the benefits of thrombolysis in patients with an acute MI and a prior cerebrovascular event (PCE). Methods: Data were derived from 2 nationwide surveys of 2012 consecutive patients with acute MI admitted to all 25 coronary care units in Israel during 1992 and 1994. Thrombolytic therapy was given to patients with a PCE at the discretion of the treating physicians. Outcomes were compared between patients with an acute MI with and without a PCE and between patients with a PCE treated with or excluded from thrombolysis. Results: Patients with a PCE (n=115 [6%]) were older, with higher rates of atherosclerotic risk factors and in-hospital complications than their counterparts without a prior event (n=1897). They were treated less often with thrombolysis or mechanical reperfusion. The 1-year mortality rates were higher among patients with a PCE (28% vs 19%, P[is less than].01), but not after multivariate adjustments for clinical characteristics (adjusted hazard ratio, 1.08; 95% confidence interval, 0.75-1.55). Patients with an acute MI and a PCE who were treated with thrombolysis (n=29 [25%]) were compared with 46 patients found ineligible for thrombolysis primarily because of their PCE. The timing of the PCE was comparable in both groups (one fifth in the preceding year), while prior transient ischemic attacks were more prevalent among patients who had undergone thrombolysis. The patients who were treated with thrombolysis (n=29) were older, had a higher rate of anterior infarction, and, while in the hospital, received aspirin, anticoagulants, and [Beta]-blockers more often than their counterparts (n=46). In-hospital intracranial hemorrhage did not occur in either group. The 1-year mortality rates were 2-fold higher among patients who had not undergone thrombolysis compared with those who had (33% vs 18%; adjusted hazard ratio, 2.44; 95% confidence interval, 0.78-7.64). Conclusions: These findings, derived from 2 nationwide surveys of consecutive patients with acute MI, suggest that patients with PCEs have an adverse outcome attributed to their older age and less favorable risk profile. Thrombolytic therapy, however, based on our preliminary data, may be beneficial in selected patients with an acute MI with a nonrecent PCE. Arch Intern Med. 1998;158:601-606

PURPOSE: The aim of this study was to determine the proportion of patients with acute myocardial infarction (AMI) excluded from thrombolytic therapy on a national basis and to evaluate the prognosis of these patients by reasons of ineligibility and according to the alternative therapies that they received during hospitalization. PATIENTS AND METHODS: During a national survey, 1,014 consecutive patients with AMI were hospitalized in all the 25 coronary care units operating in Israel. RESULTS: Three hundred and eighty-three patients (38%) were treated with a thrombolytic agent and included in the GUSTO study. Ineligible patients for GUSTO were treated: (1) without any reperfusion therapy (n = 449), (2) by mechanical revascularization (n = 97), or (3) given 1.5 million units of streptokinase (n = 85) outside of the GUSTO protocol. The in-hospital and 1-year post-discharge mortality rates were 6% and 2% in patients included in the GUSTO study; 6% and 5% in those mechanically reperfused; 15% and 10% in those treated with thromoblysis despite ineligibility for the GUSTO trial, and 15% and 13% among patients not treated with any reperfusion therapy. CONCLUSIONS: Ineligibility for thrombolysis among patients with AMI remains high. Patients ineligible for thrombolysis according to the GUSTO criteria, but nevertheless treated with a thrombolytic agent were exposed to an increased risk.

Background: Since the introduction of thrombolytic therapy for patients with acute myocardial infarction, the use of coronary angiography has substantially increased. We sought to determine whether the presence of on-site coronary angiographic facilities influenced the utilization of coronary procedures in patients with acute myocardial infarction hospitalized in Israel's coronary care units. Methods: A prospective survey was conducted in January and February 1992 in the 25 coronary care units operating in Israel, 15 of which had on-site catheterization facilities. Data on demographics, clinical features, thrombolytic therapy, and the type of coronary diagnostic or therapeutic procedures performed during the current in-hospital stay were recorded. Mortality, both in-hospital and 1 year after discharge, was assessed for all patients in the survey. Results: One thousand fourteen consecutive patients with acute myocardial infarction were hospitalized during the survey, 307 (30%) of whom were admitted to 10 coronary care units without and 707 of whom were treated in hospitals with on-site coronary angiography facilities. Demographic and baseline characteristics were similar in both groups. Thrombolytic therapy was provided equally (46%) to patients admitted to hospital with and without catheterization laboratories. Patients admitted to hospitals with these laboratories underwent coronary angiography (26%) and percutaneous transluminal angioplasty and/or coronary artery bypass grafting (12%) in greater numbers than counterparts admitted to hospitals without such laboratories (10% and 5%, respectively). Hospital and cumulative 1-year mortality rates were 11% and 18%, respectively, in patients admitted to hospitals with on-site catheterization facilities vs 10% and 17%, respectively, in the patient group admitted to the other hospitals. Patients receiving thrombolytic therapy had similar hospital mortality rates unrelated to the availability of coronary catheterization laboratories. Conclusion: This national survey showed that the availability of invasive coronary facilities led to increased use of diagnostic and therapeutic coronary procedures among patients with acute myocardial infarction. There was no difference in hospital or 1-year mortality rates in patients admitted to hospitals with or without on-site coronary angiographic facilities.

A national study was performed in early 1992 in the 25 operating coronary care units in Israel, which enabled the assessment of whether the therapeutic management of patients with acute myocardial infarction was affected by patient gender. During a 2-month period, 1,014 consecutive patients with acute myocardial infarction were hospitalized. Thrombolytic therapy wa given to 47% of men (362 of 769), and 43% of women 106 of 245) (p = NS). After adjustment for age, no gender differences in the administration of thrombolytic therapy were noted (odds ration 0.95; 95% confidence interval 0.73-1.23). Coronary angiography was more frequently performed n men (22%) than in women (16%) (p

Heart attacks (myocardial infarction) occur when ischemia (decrease in oxygen supply due to reduced or no blood flow) is so severe that a portion of the heart muscle can not function and may die. Heart attacks may be precipitated by the lodging or formation of a clot in a coronary artery. A relatively novel therapeutic approach has been to give thrombolytic (clot-breaking) agents that disrupt the clot and restore blood flow. However, thrombolytic therapy is not successful in a number of heart attack patients, who may need emergency treatment if they are to survive. To improve survival of patients with myocardial infarction, it is important to determine which patients are most likely to be responsive to thrombolytic therapy. Electrocardiogram provides an indication of heart function during each heartbeat, and elevation of the ST segment of the electrocardiogram has generally been regarded as an indicator of heart ischemia. However, some studies have suggested that ST elevation is not sensitive enough to detect restoration of coronary artery flow following a heart attack. The usefulness of ST elevation and other indicators of heart function were evaluated in 286 heart attack patients treated with alteplase, a thrombolytic agent. Alteplase was given within four hours of symptom onset, the period when thrombolytic therapy is most likely to be effective. ST elevation diminished quickly in 189 patients, but persisted in 97 patients. Rapid resolution of ST elevation was significantly associated with a good medical outcome; the group in which this occurred had a better initial medical status. However, early reperfusion was independent of this factor and correlated significantly with better heart function and a lower rate of illness and death. Although angiography was used to determine if reperfusion of coronary arteries occurred, correction of ST segment elevation was a better predictor of medical outcome. Rapid resolution of pain was not associated with persistent elevation or normalization of ST segment. Resolution of ST elevation may also reflect the contribution of other factors important to survival of heart tissue, as well as reperfusion. The results also indicate that high-risk patients, such as those with congestive heart failure, may require additional therapy, in spite of resolution of ST elevation. (Consumer Summary produced by Reliance Medical Information, Inc.)

Although both the European Cooperative Study Group and the Thrombolysis in Myocardial Infarcdon IIB trial indicated that aregiography and angioplasty as routine measures after thrombolytic treatment do not improve clincal outcome in patients with acute myocardial infraction, the potential benefit of angioplasty may have been negated by the fact that the precedure was too soon ( (Am J Cardiol 1990;66:538-545), A major heart attack, or an acute myocardial infarction (MI), results from the deterioration of heart tissue due to the cessation of blood supply to the heart. Patients with MI are treated with thrombolytic agents that break up blood clots blocking the blood supply to the heart. Invasive procedures, such as angiography (the X-ray of the blood vessels supplying the heart) and angioplasty (the repair of the narrowed or obstructed blood vessels) may also be performed. Studies have shown that such invasive procedures do not improve the outcome of patients with MI after thrombolytic therapy. However, it is possible that angioplasty is not beneficial when it is performed too early (less than 32 hours after admission). The effectiveness of delayed angioplasty was compared with that of conservative treatment in 201 patients with acute MI. All patients received recombinant-type plasminogen activator, which prevents blood clot formation. The invasive group consisted of 97 patients who underwent angiography and angioplasty five days after drug treatment. The conservative group consisted of 104 patients who only underwent angiography after recurrent chest pain associated with MI or exercise. In the invasive group, 92 patients underwent angiography, 49 had angioplasty, and 11 required coronary artery bypass grafting (CABG), a surgical procedure to restore the blood flow to the heart. Among patients of the conservative group, 40 developed ischemia, an insufficient blood supply to the heart; 39 underwent angiography; 20 had angioplasty; and four required CABG. The recurrence of MI and maintenance of left ventricle function were similar for both invasive and conservative groups eight weeks after discharge from the hospital. If only the deaths which occurred after the scheduled invasive procedures are considered, 5 of 97 patients in the invasive group and none of 100 patients of the conservative group died within the 10-month follow-up period. Re-hospitalization was more frequent among patients of the conservative group and was associated with a history of chest pain. These findings suggest that conservative treatment is preferable to invasive treatment of patients with acute MI. (Consumer Summary produced by Reliance Medical Information, Inc.)

A very important aspect in the successful treatment of patients following an acute myocardial infarction (MI) is prompt initiation of thrombolytic treatment. Thrombolysis relies upon drugs that are capable of dissolving clots in the area of the infarction, the tissue death resulting from reduced blood supply. A thrombolytic agent has been demonstrated to be most effective if administered within two hours after the onset of pain. This prompt drug therapy can preserve heart function, specifically, left ventricular function, and can reduce short- and long-term mortality. The goal of this study was to correlate clinical outcome with the time from onset of symptoms to initiation of thrombolytic treatment with a recently approved new drug, recombinant tissue plasminogen activator (rt-PA). One hundred ninety patients with AMI were administered rt-PA an average of two hours after the onset of their symptoms. Prehospitalization thrombolysis was possible in a substantial number of these patients by use of mobile intensive care units. Short- and long-term effects of early versus late administration of rt-PA were evaluated by examining left ventricular function, and cardiac morbidity and mortality. The overall two-year mortality was low; there were 10 deaths out of the 190 patients treated. Eight of those deaths (4 percent) were cardiac in nature. The patients that were treated within two hours from the onset of symptoms had a lower 60-day and 24-month mortality than patients treated two to four hours after symptoms began. It is also important to understand that the 96 patients who received early treatment were generally more seriously ill, which can be interpreted to mean that sicker patients seek treatment sooner. It is essential that patients seek early treatment in order to salvage heart muscle tissue. Unfortunately, many patients delay seeking treatment by one to two hours and the initiation of valuable thrombolytic treatment is delayed. Mobile intensive care units are valuable in providing treatment early in the homes of patients and this method was found to be both safe and effective. The authors recommend this prehospital therapy to shorten the interval between symptom onset and treatment initiation to potentially reduce mortality. (Consumer Summary produced by Reliance Medical Information, Inc.)

Patients with cardiac arrhythmias, sudden cardiac death, and acute myocardial infarction (MI, heart attack) have been shown recently to have low levels of magnesium in their blood. Low levels of magnesium have also been identified in heart muscle tissue of patients with AMI. A disturbance of magnesium is believed to occur in the acute phase of the MI and there is a high incidence of life-threatening arrhythmias and high mortality during this initial period. Blood levels of magnesium in patients that survive an MI are generally low or normal. Patients diagnosed with acute MI were given either magnesium sulfate injection or placebo shortly after admission, and the incidence of cardiac arrhythmias and congestive heart failure and hospital mortality were examined. A variety of arrhythmias were seen in 45 percent of patients who received placebo and 32 percent of patients who received magnesium. There was a higher mortality in the placebo group, with a total of nine deaths, with only one death in the magnesium group. Rapid administration of magnesium by intravenous injection has a possible protective role; however, it is unknown whether this is due to correction of a condition of low magnesium (hypomagnesemia) or to an increase of magnesium to above normal levels. This study was conducted before the routine use of thrombolytic agents was initiated in the coronary care unit, but magnesium should be considered a safe, simple, and inexpensive method of reducing immediate mortality in patients with MI. (Consumer Summary produced by Reliance Medical Information, Inc.)

To cardiologists, the term ''late potentials'' refers to electrical signals seen on an electrocardiogram (ECG) at the end of what is called the QRS complex or during the ST segment of the heartbeat. It is thought that these signals come from areas in the heart muscle where the electrical impulses have been slowed because of the damage done in those areas. If that is true, then late potentials may be indicators that arrhythmias may occur. When late potentials occur one to four weeks after an acute myocardial infarction (heart attack or AMI; death of heart tissue due to a loss of blood supply), they are carry a higher risk of sudden cardiac death and ventricular tachycardia (ineffective rapid beating of the ventricles) in the next 6 to 24 months. Thrombolytic therapy involves injection into the heart of enzymes to dissolve an existing blood clot in a heart vessel. Performed within a few hours of AMI, thrombolytic therapy has been shown to improve not only patient survival, but to preserve heart muscle (myocardial) function as well. This study of 158 patients during the first 10 days after AMI compared the occurrence of late potentials in patients who did and those who did not receive thrombolytic therapy. Late potentials occurred at about the same rate in both groups in the first two days after infarction. But the incidence of late potentials increased significantly in the untreated group after 7 to 10 days. Thrombolytic therapy does seem to reduce the development of late potentials. Since late potentials and fatal arrhythmias are associated, thrombolytic therapy within four hours of AMI may explain the reduced mortality rate associated with it. (Consumer Summary produced by Reliance Medical Information, Inc.)

Acute myocardial infarction (AMI), heart attack, occurs when an acute partial or total obstruction of one or more coronary arteries results in a reduction of blood flow to the heart (myocardial ischemia). This can cause permanent damage to the cardiac muscle, which in severe cases causes death. A common therapeutic approach to AMI is the administration of thrombolytic (clot-dissolving) drugs such as streptokinase or tissue plasminogen activator. It has been reported that impairment of liver function may be a side effect of thrombolytic therapy. To study the effects of thrombolysis on liver function in more detail, 108 consecutive AMI patients were randomly assigned to receive either recombinant tissue-type plasminogen activator (r-TPA) or streptokinase intravenously. Liver function was determined by measuring bilirubin, and levels of the liver enzymes alkaline phosphatase, alanine aminotransferase, and gamma glutamyl transferase. These measurements were performed at admission, at five-day intervals, and at three-month follow-up. Thirty-two patients who did not consent to thrombolytic therapy or who were excluded from treatment for a variety of reasons were used as an untreated control group. Levels of all three liver enzymes were significantly increased during hospitalization in the patients receiving streptokinase; in the r-TPA group, only alanine aminotransferase showed any tendency to increase. All changes had normalized in both groups by the time of the three-month follow-up. Since r-TPA induced less elevation of liver enzymes than streptokinase, it should probably be the drug of choice for patients with impaired liver function who require thrombolysis. (Consumer Summary produced by Reliance Medical Information, Inc.)