Ann Thorac Surg 1995;59:1169-1176
© 1995 The Society of Thoracic Surgeons
Coronary Artery Bypass Grafting Within 30 Days of an Acute Myocardial Infarction
Tej K. Kaul, FRCS,
Barry L. Fields, MD,
Shefton L. Riggins, MD,
Guillermo C. Dacumos, MD,
David A. Wyatt, MD,
Christopher R. Jones, MD
Division of Cardiac Surgery, Princeton Baptist Medical Center, Birmingham, Alabama
Accepted for publication January 28, 1995.
 |
Abstract
|
|---|
Risks and benefits of performing coronary artery bypass grafting (CABG) within 30 days of an acute myocardial infarction (AMI) were examined. In 642 patients operated on between January 1988 and December 1993, emergent CABG was performed in 46 patients for cardiogenic shock mainly for failed thrombolysis in patients with an evolving AMI. The remaining patients underwent urgent (<72 hours) or elective (>72 hours) revascularization for failed percutaneous transluminal coronary angioplasty (n = 73), postinfarction angina (n = 381), vein graft stenosis (n = 100), and complications after an AMI (n = 42). In patients who underwent primary CABG for an uncomplicated AMI, the infarct was subendocardial in 68, anterolateral or septal in 200, inferior or posteroinferior in 200, and posterolateral in 32 patients. Early mortality (<30 days) was 5.9% for the entire series and 0%, 4.5%, 4.5%, 29%, 9%, 8%, 10%, and 26% for the subsets of patients with subendocardial infarct, anterolateral or septal infarct, inferior or posteroinferior infarct, ischemic mitral regurgitation, left ventricular aneurysm, redo CABG, age more than 70 years, and left ventricular ejection fraction less than 0.30, respectively. By multivariate analysis, independent predictors of early mortality were left ventricular ejection fraction less than 0.30, age more than 70 years, and cardiogenic shock. Five-year survival for the subsets of patients with subendocardial infarct, anterolateral or septal infarct, inferior or posteroinferior infarct, ischemic mitral regurgitation, left ventricular aneurysm, redo CABG, age greater than 70 years, and left ventricular ejection fraction less than 0.30 were 94%, 75%, 70%, 39%, 88%, 74%, 73%, and 52%; and cardiac event-free survivals were 66%, 68%, 73%, 22%, 68%, 62%, 62%, and 42%, respectively. Emergent or urgent CABG for AMI is indicated in case of evolving AMI with failed tissue plasminogen activator or percutaneous transluminal coronary angioplasty, postinfarction angina, and complications after AMI. Early revascularization is preferred in patients with an uncomplicated AMI in the presence of persistent ischemia or life-threatening coronary anatomy.
|
Introduction
|
|---|
Acute myocardial infarction (AMI) remains the most important cause of death in the western hemisphere [1]. Prognosis after an episode of AMI depends on the myocardial function lost, risk of infarct extension or reinfarction, and the measures taken to revascularize the salvageable myocardium. The timing of revascularization after an episode of AMI has remained controversial. Conventional wisdom in the past had favored a conservative approach because the risks of early coronary artery bypass grafting (CABG) after an AMI were too high [2]. However, delayed revascularization carries a risk of infarct completion or extension [3, 4] and ultimately a poor survival [3]. Conversely, early revascularization has been shown to limit the infarct size [5], reduce electromechanical ventricular dysfunction, and improve patient survival [6]. During the last decade an aggressive policy has been recommended to revascularize salvageable myocardium after an episode of AMI [7]. At present, most medical centers initially would use intravenous or intracoronary thrombolysis [1, 8], percutaneous transluminal coronary angioplasty (PTCA) [8, 9], or a combination of these to open an occluded coronary artery. Coronary artery bypass grafting frequently is considered to be the most reliable method to salvage the ischemic myocardium [4, 9–11], especially when thrombolysis and PTCA have failed. In this retrospective study, risks and benefits of performing CABG within 30 days of an AMI have been evaluated.
|
Patients and Methods
|
|---|
Between January 1988 and December 1993, 2,922 consecutive patients were admitted with an AMI to our medical center. Of these, 642 patients (22%) underwent CABG within 30 days of an episode of AMI (Appendix 1). Mean age was 66 ± 3.6 years, 26.6% (n = 171) were 70 years or older, and 75.23% (n = 483) were male. In order of frequency coronary risk factors present in this series were systemic hypertension (39%; n = 251), diabetes mellitus (20.7%; n = 133), smoking (19.4%; n = 125), hyperlipidemia (9.8%; n = 63), a family history of coronary artery disease (8.56%; n = 55), and a previous history of AMI (9%; n = 58). Indications for surgical intervention, infarct location, its sequlae, and timing of operation are summarized in Tables 1–4.
View this table:
[in this window]
[in a new window]
|
Table 2. . Perioperative Mortality (30 days) and Hospital Mortality for CABG in Relation to Infarct Location and Sequelae in 642 Patients
|
|
In this series, 150 patients were admitted within 6 hours of onset of an AMI. During these early hours, an attempt was made to recanalize the infarct-related coronary artery by thrombolytic therapy (intracoronary in 43 and intravenous in 100) or with PTCA (n = 7). All remaining patients were hospitalized within the next 72 hours.
Electrocardiographic monitoring and a serial estimation of creatine kinase (CK) and CK-MB were made in our medical center or in a referring center to establish the diagnosis of AMI and to differentiate between transmural (new Q wave, ST-T elevation greater than 1 mm in one or two leads and an increase in CK-MB value to 13% to 33% of the total CK value) and nontransmural AMI (ST-T elevation of greater than 1 mm in one or two leads, absence of a Q wave, and CK-MB value greater than 10 IU units or greater than 8% of total CK value). Measurements of CK-MB also were made to confirm the diagnosis of reinfarction, infarct extension, or postoperative myocardial infarction. Although CK-MB measurement is regarded as a most sensitive index of myocardial necrosis, its limitations in quantification of an AMI, especially in patients undergoing thrombolytic therapy, PTCA, or CABG, are well known [1]. Therefore, to assess the viability and functional status of the myocardium, we mainly have relied on two-dimensional echocardiography, multigated acquisition scan, and dipyridamole thallium 201 scintigraphy. These were repeated as indicated. Concomitantly, coronary angiography was performed in almost 70% of our patients within the first week after an episode of AMI. During the second week a limited exercise test, along with electrocardiographic monitoring and a thallium scan were performed to detect the element of ischemia before coronary angiography.
Only a few patients with a nontransmural AMI were allowed home, and they were readmitted on reappearance of symptoms. All other patients in this series underwent surgical intervention during a single hospital admission. An emergent surgical revascularization (<6 hours) was performed for refractory cardiogenic shock (systolic blood pressure <90 mm Hg; cardiac index, 1.8 L/m2; pulmonary capillary wedge pressure >20 mm Hg; no improvement with inotropic support or intraaortic balloon pump support) in 46 patients (7.16%), and urgent CABG (<72 hours) in 40.65% (n = 261), predominantly for failed PTCA (n = 73), inadequate relief with thrombolytic therapy, or postinfarction angina. Mean interval between the initiation of thrombolytic therapy and CABG was 4.6 ± 0.4 days. By 2
weeks 95.56% of our patients were operated on predominantly for postinfarction angina (n = 381), the presence of a critical coronary arterial stenosis in patients with a previous coronary artery operation (n = 87), or a complication after an AMI (n = 20). In 20 (4.35%) remaining patients (10 redo and 18 with a complication after an AMI), surgical intervention was delayed in view of extensive myocardial necrosis but these patients had a satisfactory response to medical therapy or circulatory support (or both). Other preoperative features present in these patients were cerebrovascular accident (n = 12), permanent pacemaker insertion for complete heart block (n = 14), temporary pacing (n = 6), and thrombocytopenic purpura or polycythemica (n = 3). The subgroup of patients with an anterior AMI had more patients with a left ventricular ejection fraction (LVEF) less than 0.30 than the subgroup of patients presenting with an inferior myocardial infarction (17% versus 8%; p < 0.01) or a subendocardial infarction (17% versus 10.3%; not significant). The subgroup of patients presenting with an anterior infarction also had a greater number of patients on preoperative intraaortic balloon pump support (16%) than the other subgroups, but the differences were not significant.
Standard cardiopulmonary bypass with moderate hypothermia (28°C) was used in all cases. Cold blood cardioplegia was delivered by combined antegrade retrograde route or via retrograde route alone in the reoperative patients. An internal thoracic artery was used in 156 patients (24.3%; 115 primary CABG and 41 reoperative CABG). The internal thoracic artery had to be used infrequently because of hemodynamic instability and unpredictability of graftable vessels [9] in a large number of our patients. As of April 1994, follow-up was complete in all patients by records of outpatient attendance, telephone contact, or questionnaire.
The values are expressed as mean ± standard error of the mean or as percent of the total. Paired data were compared by Student's t test, unpaired data by 
2 or Fisher's exact test for univariate analysis. All variables listed in Tables 1 through 4
were entered for univariate analysis to determine the predictors of perioperative (30-day) and hospital mortality (all deaths during hospitalization after operation), which were no different. The variables with a p value less than 0.1 then were entered for stepwise multivariate analysis. The variables entered to determine the independent predictors of 30-day mortality were female sex, age greater than 70 years, hypertension, diabetes, preoperative congestive heart failure, cardiogenic shock, postinfarction angina, left main coronary artery disease, two-vessel or one-vessel occlusion, LVEF less than 0.30, and ischemic mitral regurgitation. The following variables were entered for Cox's proportional hazard model (risk factor present versus risk factor absent) to detect the predictors of late survival: age greater than 70 years; double-vessel coronary occlusion; single-vessel coronary occlusion; left main coronary artery disease; preoperative congestive heart failure; ventricular dysrhythmias; anterior, inferior, or subendocardial infarction; and LVEF less than 0.30. Actuarial analysis (Kaplan-Meier) was used to construct survival and event-free survival curves, which then were compared with Mantel's test [12]. A p value less than 0.05 was considered significant. Statistical software (Statpack) developed locally was used for all statistical analysis.
|
Results
|
|---|
Perioperative (30-day) as well as hospital mortality for the entire series was 5.9% (38/642). Table 2 shows hospital mortality for the pertinent subsets of patients, and Table 3 shows important differences between the pertinent subsets of our patients. Timing of surgical intervention at variable intervals within 30 days after an AMI had no significant impact on hospital mortality (see Table 4). The predictors of hospital mortality by univariate and multivariate analysis are shown in Table 5. Postoperative complications causing mortality and morbidity are outlined in Table 6. Cumulative survival and cardiac event-free survival (cardiac-related deaths, PTCA, redo CABG, myocardial infarction class IV angina) of our patients with an uncomplicated AMI are summarized in Table 7. Cumulative survival and cardiac event-free survival of the other pertinent subsets of patients is shown in Table 8. Causes of late deaths were as follows:
Ischemic cardiomyopathy46 Ventricular tachycardia/ventricular fibrillation4 Multiorgan failure2 Aspiration pneumonia1 Suicide1 Cancer2 Graft closure2 Renal failure2 Unknown2 Late mitral regurgitation2 Mediastinitis2
The only significant predictor of late mortality by Cox proportional hazard model was LVEF less than 0.30 (Fig 1).
View larger version (28K):
[in this window]
[in a new window]
|
Fig 1. . (A) Cumulative 5-year survival after coronary artery bypass grafting for patients with a left ventricular ejection fraction (LVEF) less than 0.30 versus remaining patients in the series. (B) Parametric representation of (A) showing a higher mortality for the patients with LVEF 0.30 in both early and the late phase as compared with the remaining patients in the series. (AMI = acute myocardial infarction; CL = confidence limits.)
|
|
|
Comment
|
|---|
Patients with an AMI may present with diverse clinical problems depending on infarct location, its extent, and the associated complications. It is now well established that the patients treated with conventional medical therapy for AMI have a higher hospital mortality (16%) and a poor long-term survival [12]. Recent reports clearly have demonstrated the benefits of early surgical revascularization in these patients [4, 8–11]. However, there has been a wide variation in the perioperative mortality reported for these patients (Table 9) [3–6, 13–19]. This has been influenced by a number of variables and the timing of CABG in the presence of these variables. The timing of CABG is important in the subset of patients with evolving AMI (mainly for failed thrombolysis or PTCA) [5, 6, 9, 13], postinfarction angina [4, 9, 20–22], rupture of an infarcted myocardium [23], failed PTCA [24], subendocardial infarcts [25], cardiogenic shock [3, 5, 13, 16, 18], advanced age [3], and poor left ventricular function (LVEF <0.30) [18].
CABG for an Uncomplicated AMI
Earlier reports have quoted a high perioperative mortality (7.7% to 46%) [16, 19] for these patients who were operated on between 2 and 7 days after an AMI. In our series and in the most recent reports [3, 18, 22], timing of CABG at intervals within 30 days of an uncomplicated AMI had no significant effect on perioperative mortality. This has been attributed to an improvement in myocardial protection and patient management techniques [3]. Patients who remain stable after an uncomplicated AMI are best suited for elective surgical intervention well after the infarct has healed [1]. An infarct is considered healed when symptoms have subsided, CK-MB level has returned to the baseline, and the electrocardiogram no longer shows evidence of ischemia, ectopy, or arrhythmias [1]. However, evidence in the literature clearly suggests that subsets of the patients in this group in whom postinfarction angina develops or who have clear evidence of threatened ischemia due to critical lesions in the non–infarct-related major coronary vessels are at considerable risk of reinfarction or infarct extension [4]. These patients invariably require urgent or semiurgent revascularization [4, 11]. Our practice has been in accord with this policy.
CABG for an Evolving Myocardial Infarction
Evidence in the literature indicates that early revascularization (6 to 8 hours) for an evolving myocardial infarction is beneficial [5, 6, 13]. At this stage myocardial revascularization would limit the infarct size [5], preserve global and regional myocardial function [5], and improve patient survival [6]. Previous reports clearly have shown that surgical intervention at this stage resulted in a lower perioperative mortality and a better longer-term survival than by operating later [5, 13]. At present, generally an evolving AMI is treated with thrombolytic therapy or PTCA [1, 9]. In this series, when these measures failed, emergent CABG was performed as these patients were also in cardiogenic shock.
CABG for Postinfarction Angina
It is now well recognized that at least 15% of patients after an AMI [16] remain at risk of postinfarction angina or reinfarction [20–22]. Therefore, it has been considered a most frequent as well as an important indication of urgent revascularization early after an AMI [8–10, 16, 21, 22]. In a large series reported by Floten and associates [4] 63% of the patients underwent CABG within 30 days of an AMI for postinfarction angina. Similarly 59.3% of our patients also required urgent or semiurgent surgical intervention for life-threatening continuous ischemia early after an AMI. Invariably these patients also have a critical lesion in the non–infarct-related coronary arteries [22]. The natural history of these patients is dismal, with as many as 56% dying within 6 months and a further 16% having recurrent AMI or requiring CABG [16].
Repair and Revascularization for Ruptured Myocardial Infarct
Complete rupture of the infarcted myocardium usually presents as a surgical emergency with cardiogenic shock or heart failure [23]. The incidence of this complication has varied considerably in clinical and autopsy reports [23]. In patients with occlusive coronary artery disease, the reported incidence of free wall rupture was 10%, postinfarct ventricular septal defect 8%, and rupture of a papillary muscle 4% [26]. In this series only 2 patients (0.3%) presented with an acute rupture of an anterior infarct. Both such patients underwent a successful repair using a standard technique [27] within 24 hours along with CABG. Only 1 patient in this series presented with a large basal ventricular septal defect in association with an inferior infarct (who unfortunately died postoperatively). Prognosis of this variety of ventricular septal defect is often worse than that of an apical ventricular septal defect associated with an anterior myocardial infarction [23]. It is well known that a postinfarction ventricular septal defect causing hemodynamic instability requires urgent closure, whereas repair may be undertaken at a later stage in more stable patients when the tissues are not so fragile. In this series, mitral regurgitation due to rupture of a posteromedial papillary muscle in association with an inferior infarct (n = 12) occurred more frequently than rupture of an anterolateral infarct (n = 5). We performed repair or replacement of the valve in 11 of 17 patients within 2 weeks and in 6 of 17 more than 2 weeks after the AMI. Perioperative deaths occurred in 4 of 5 patients who remained in cardiogenic shock after operation.
Repair and Revascularization of Patients With Left Ventricular Psuedoaneurysm After an AMI
Early institution of thrombolytic therapy appears to have reduced the incidence of this complication in patients with an occluded left anterior descending coronary artery [23]. In this series the left ventricular psuedoaneurysm due to partial rupture of infarcted muscle was apical in 21 of 22 patients. Of these, 12 of 22 were operated on 2 weeks after the AMI, but the remaining patients with evidence of clot, history of congestive heart failure, or ventricular dysrhythmias were operated on as soon as possible. These patients had a low perioperative mortality (2%) and acceptable longer term survival (88% at 5 years).
CABG for Failed PTCA in Patients With AMI
Angioplasty has proved to be a very effective way to revascularize acutely ischemic myocardium [13]. However, angioplasty has its limitations in the presence of occluded lesions, especially if the lesions are long and tortuous. All such patients should undergo emergent or urgent CABG after a failed PTCA [13, 18, 24].
CABG in AMI Patients Presenting With Cardiogenic Shock
Optimal timing of surgical intervention in these patients is often difficult and most controversial [22]. Usually there is an extensive infarct, 30% to 40% noncontractile left ventricle, or serious sequelae from a transmural infarct. Hypotension caused by AMI in these patients may reduce the blood supply to the remaining myocardium further, causing hemodynamic instability and arrhythmias. As reported earlier [3, 6, 7, 13, 16–18] (Table 10), perioperative mortality of this subset of our patients clearly was higher than that for our remaining patients. It has been shown that these patients are likely to do better if they had an evolving AMI or a correctable lesion such as a ventricular septal defect, mitral regurgitation, and ruptured ventricle [23]. It appears that it is better to operate on these patients earlier and accept a higher risk of perioperative mortality than to continue with the conventional medical management [10, 17, 22] or circulatory support. The latter may be used as a bridge to cardiac transplantation [15] in a limited number of select cases. Inevitably many of these patients would succumb to multiorgan failure during the waiting period.
CABG for Subendocardial Infarction
Previous studies [7, 16, 17] clearly have shown that nontransmural infarcts are not innocuous. Almost 21% of patients after a subendocardial infarction may have development of a transmural infarct [25] or postinfarction angina [17], and up to 46% may have unstable angina or arrhythmias [26]. As recommended earlier [25] we have treated these patients aggressively [7, 16, 17], but this often was done under more stable conditions within 30 days of presentation.
Reoperative CABG in Patients With AMI
There are no clear guidelines for the management of these patients. As expected our reoperative patients had a higher perioperative mortality (8%) but an acceptable 5-year survival (74%). Our selection and management criteria for these patients were no different than those for our primary CABG patients. However, some of the reoperative patients with bilateral internal mammary grafting or diffuse coronary artery disease may require special surgical considerations (eg, conduit choice, cannulation sites, cardioplegia route).
Predictors of Early and Late Mortality
As reported earlier [6, 13, 16, 18] cardiogenic shock and poor left ventricular function (LVEF <0.30) [3, 18] were the most important predictors of perioperative mortality in our patients. By multivariate analysis other independent predictors of perioperative mortality in our series were age greater than 70 years [3, 18], female sex, diabetes, and hypertension. The only significant predictor of late mortality was LVEF less than 0.30 [2, 13]. The cumulative 5-year survival of our patients with a nontransmural infarct was most favorable, but survival of patients who had sustained an uncomplicated anterior (75%) or inferior (70%) infarct was clearly inferior as compared with our remaining uncomplicated patients who underwent CABG without an AMI (87%) during the same study period. Our patients with left ventricular aneurysm had a good (88%) long-term survival after a successful surgical correction as described previously [28], but our patients with mitral regurgitation had a poor prognosis despite successful surgical correction. To prevent fatal episodes of ventricular dysrhythmias, standard electrophysiologic testing, cryoablation, and prophylactic implantation of an implantable cardiovertor defibrillator system is recommended in select patients with severe segmental dysfunction and dysrhythmias. Patients with anterior or subendocardial infarcts continued to have a greater incidence of cardiac-related events [25, 28].
Patients with AMI are a heterogeneous group, and optimal timing of therapeutic intervention for the different subsets of patients often differs. In general, thrombolytic therapy or PTCA is used as the first line of management. Conventional medical therapy may be used in patients who are unsuitable for these treatment modalities and also in patients with a massive myocardial infarction with multisystem dysfunction. The patients who respond favorably to nonsurgical interventions are hospitalized until the infarct has healed [1], which is determined by cessation of symptoms, return of CK-MB level to baseline, and a complete absence of ischemia, ectopy, and arrhythmias on electrocardiogram [1]. These patients then are subjected to a submaximal exercise test and normally are discharged if they do not show any evidence of ischemia, ectopy, or arrhythmia and readmitted for an elective coronary angiography and CABG between 4 and 6 weeks [1]. Obviously such patients were not included in this series. This series included patients who had failed to respond to thrombolytic therapy or PTCA and underwent emergent or urgent CABG. During 1 to 2 weeks after an AMI most of our patients were operated on for postinfarction angina or for presence of a critical lesion in non–infarct-related major coronary arteries. Although some authors have reported a higher mortality after surgical intervention during this period [19], a risk of death from reinfarction or infarct extension is even higher [4].
Optimal timing of surgical intervention for the subsets of patients older than 70 years [3], those with an LVEF less than 0.30 [3], and patients in cardiogenic shock [29] is most controversial. In our patients who were 70 years old or older, delayed surgical intervention beyond 1 week of an AMI simply increased perioperative mortality due to multisystem failure. In our subset of patients with poor left ventricular due to an AMI, waiting beyond 1 week for the infarct to heal did not improve survival. As expected, in a small subset of our older patients (>70 years) with an LVEF less than 0.30 perioperative mortality was high and the long-term survival was poor. It appears that optimal timing of high-risk patients with an AMI should be guided by the relative presence of an element of ischemia or necrosis. Early surgical intervention is justified when an ischemic element is predominant. In the presence of massive necrosis, risk of surgical intervention is high at any stage after an AMI. Optimal timing of surgical intervention in such cases should be guided by the response to the conventional medical therapy and the circulatory support. If it is possible to stabilize the hemodynamic status then delayed intervention generally is preferred; otherwise, one is left with an unfortunate choice of accepting a high perioperative mortality or accepting a high risk of deaths due to multiorgan failure during the waiting period. On balance, early intervention is likely to result in a better salvage rate than delayed intervention [29].
|
Acknowledgments
|
|---|
We thank Mrs Sandra Siebert for her secretarial help in preparation of the manuscript and Mrs Melinda Hicks for assistance with follow-up of these patients.
|
Footnotes
|
|---|
Address reprint requests to Dr Fields, 817 Princeton Ave, Suite 300, Birmingham, AL 35211.
|
References
|
|---|
- ACC/AHA Task Force Report. Guidelines for the early management of patients with acute myocardial infarction. Am J Cardiol 1990;16:249–92.
- Dawson JT, Hall RJ, Hallman GL, Cooley DA. Mortality in patients undergoing coronary artery bypass surgery after myocardial infarction. Am J Cardiol 1974;33:483–6.[Medline]
- Applebaum R, House F, Rademaker A, et al. Coronary artery bypass grafting within 30 days of acute myocardial infarction. J Thorac Cardiovasc Surg 1991;102:745–52.[Abstract]
- Floten HS, Ahmad A, Swanson JS, et al. Long-term survival after postinfarction bypass operation: early versus late operation. Ann Thorac Surg 1989;48:757–63.[Abstract]
- Flameng W, Sergeant P, Vanhaecke J, Suy R. Emergency coronary bypass grafting for evolving myocardial infarction: effect on infarct size and left ventricular function. J Thorac Cardiovasc Surg 1987;94:124–31.[Abstract]
- DeWood MA, Spores J, Berg R Jr. et al. Acute myocardial infarction: a decade of experience in 701 patients. Circulation 1983;68(Suppl 2):8–16.
- Braunwald E. The aggressive treatment of acute myocardial infarction. Circulation 1985;71:1087–92.[Free Full Text]
- Nicolau JC, Ardito RV, Garzon SAC, et al. Surgical revascularization after fibrinolysis in acute myocardial infarction. J Thorac Cardiovasc Surg 1994;107:1454–9.[Abstract/Free Full Text]
- Von Segesser LK, Popp J, Amann FW, Turina MI. Surgical revascularization in acute myocardial infarction. Eur J Cardiothorac Surg 1994;8:363–9.[Abstract]
- Sintek CF, Pfeffer TA, Khonsari S. Surgical revascularization after an acute myocardial infarction. J Thorac Cardiovasc Surg 1994;107:1317–22.[Abstract/Free Full Text]
- Naunheim KS, Kesler KA, Kanter KR, Zeef RH. Coronary artery bypass for recent infarction predictors of mortality. Circulation 1988;78(Suppl 1):122–8.
- Mantel N. Evaluation of survival data and two new rank order statistics arising in its consideration. Cancer Chemother Rep 1966;50:163–70.[Medline]
- Phillips SJ, Kongthaworn C, Skinner JR, Zeff RH. Emergency coronary artery reperfusion: a choice therapy for evolving myocardial infarction. Results in 339 patients. J Thorac Cardiovasc Surg 1983;86:679–88.[Abstract]
- Pacifico AD. Surgery for acute myocardial infarction. Ala J Med Sci 1986;23:169–72.[Medline]
- Katz NM, Kubanick TE, Ahmed SW, et al. Determinants of cardiac failure after coronary bypass surgery within 30 days of acute myocardial infarction. Ann Thorac Surg 1986;42:658–63.[Abstract]
- Nunley DL, Grunkemeier GL, Tepley JF, et al. Coronary bypass operation following acute complicated myocardial infarction. J Thorac Cardiovasc Surg 1983;85:485–91.[Abstract]
- Jones RN, Pifarré R, Sullivan HJ, et al. Early myocardial revascularization for postinfarction angina. Ann Thorac Surg 1987;44:159–63.[Abstract]
- Athanasuleas CL, Geer DA, Arciniegas JG, et al. A reappraisal of surgical intervention for acute myocardial infarction. J Thorac Cardiovasc Surg 1987;93:405–14.[Abstract]
- Hochberg MS, Parsonnet V, Gielchinsky I, et al. Timing of coronary revascularization after acute myocardial infarction. Early and late results in patients revascularized within 7 weeks. J Thorac Cardiovasc Surg 1984;88:914–21.[Abstract]
- Levine FH, Gold HK, Leinbach RC. Safe early revascularization for continuing ischemia after acute myocardial infarction. Circulation 1979;60(Part 1):5–9.
- Breyer RH, Engelman RM, Rousou JA, Lameshow S. Postinfarction angina: an expanding subset of patients undergoing coronary artery bypass. J Thorac Cardiovasc Surg 1985;90:532–40.[Abstract]
- Baumgartner WA, Borkon AM, Zibulewsky J, et al. Operative intervention for postinfarction angina. Ann Thorac Surg 1984;38:265–7.[Abstract]
- Pasternak RC, Braunwald E, Sobel BE. Acute myocardial infarction. In: Braunwald E, ed. Heart disease. A text book of cardiovascular medicine. Philadelphia: Saunders, 1992: 1200–91.
- Parsonnet V, Fisch D, Gielchinsky I, et al. Emergency operation after failed angioplasty. J Thorac Cardiovasc Surg 1988;96:198–203.[Abstract]
- Madigan NP, Rutherford BD, Frye RL. The clinical course, early prognosis and coronary anatomy of subendocardial infarct. Am J Med 1976;60:634–41.[Medline]
- Dubnow MH, Burchell HB, Titus JL. Postinfarction ventricular aneurysm: a clinicopathological and electrocardiographic study of 80 cases. Am Heart J 1965;70:753–60.[Medline]
- Stiegel M, Zimmern SH, Robicsek F. Left ventricular rupture following coronary occlusion treated by streptokinase infusion: successful surgical repair. Ann Thorac Surg 1987;44:413–5.[Abstract]
- Geltman EM, Ehsani AA, Campbell MK, Schechtman K, Roberts R, Sobel BE. The influence of location and extent of myocardial infarction on long term ventricular dysrhythmias and mortality. Circulation 1979;60:805–14.[Free Full Text]
- Guyton RA, Arcidi JM, Langford DA, Morris DC, Liberman HA, Hatcher CR Jr. Emergency coronary bypass for cardiogenic shock. Circulation 1987;76(Suppl 5):22–7.
This article has been cited by other articles:
|
|
|
|
 
K. Fattouch, F. Guccione, P. Dioguardi, R. Sampognaro, E. Corrado, M. Caruso, and G. Ruvolo
Off-pump versus on-pump myocardial revascularization in patients with ST-segment elevation myocardial infarction: a randomized trial.
J. Thorac. Cardiovasc. Surg.,
March 1, 2009;
137(3):
650 - 656.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
K. Miyahara, A. Matsuura, H. Takemura, S. Saito, S. Sawaki, T. Yoshioka, and H. Ito
On-pump beating-heart coronary artery bypass grafting after acute myocardial infarction has lower mortality and morbidity
J. Thorac. Cardiovasc. Surg.,
March 1, 2008;
135(3):
521 - 526.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
A. J. Rastan, J. I. Eckenstein, B. Hentschel, A. K. Funkat, J. F. Gummert, N. Doll, T. Walther, V. Falk, and F. W. Mohr
Emergency Coronary Artery Bypass Graft Surgery for Acute Coronary Syndrome: Beating Heart Versus Conventional Cardioplegic Cardiac Arrest Strategies
Circulation,
July 4, 2006;
114(1_suppl):
I-477 - I-485.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
H. Hirose, A. Amano, S. Yoshida, T. Nagao, H. Sunami, A. Takahashi, and N. Nagano
Surgical management of unstable patients in the evolving phase of acute myocardial infarction
Ann. Thorac. Surg.,
February 1, 2000;
69(2):
425 - 428.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
K. A. Eagle, R. A. Guyton, R. Davidoff, G. A. Ewy, J. Fonger, T. J. Gardner, J. P. Gott, H. C. Herrmann, R. A. Marlow, W. C. Nugent, et al.
ACC/AHA guidelines for coronary artery bypass graft surgery: A report of the American College of Cardiology/ American Heart Association task force on Practice Guidelines (Committee to revise the 1991 Guidelines for Coronary Artery Bypass Graft Surgery)
J. Am. Coll. Cardiol.,
October 1, 1999;
34(4):
1262 - 1347.
[Full Text]
[PDF]
|
|
|
Top
Abstract
Introduction
