Clinical characteristics and long-term outcome of patients in whom congestive heart failure develops after thrombolytic therapy for acute myocardial infarction: development of a predictive model

Ischemic heart disease is the most common cause of congestive heart failure, which often begins after acute myocardial infarction. To better delineate the clinical characteristics and outcomes of patients in whom congestive heart failure develops after acute myocardial infarction in the thrombolytic era, we prospectively evaluated patients enrolled in six of the TAMI trials. The study cohort comprised 1619 consecutive patients who had at least 1 mm of ST-segment elevation in two contiguous electrocardiographic leads within 6 hours of the onset of acute myocardial infarction and who received intravenous thrombolytic therapy. We prospectively collected clinical characteristics, baseline demographics, acute and 1-week angiographic variables, and in-hospital and 1-year outcome data. We performed stepwise multivariable regression analysis to determine the noninvasive and invasive predictors of the development of in-hospital congestive heart failure. Congestive heart failure developed in 301 patients in the hospital (19% of 1521 patients admitted were not in heart failure). These patients were likely to be older and female, have diabetes mellitus and previous myocardial infarction, and have an anterior wall myocardial infarction. On acute angiography, they had lower ejection fractions and a higher incidence of multivessel disease. Patency at 90 minutes was lower in the patients with congestive heart failure, and acute mitral regurgitation occurred in 1.6% versus 0.21% of patients without congestive heart failure. Patients with congestive heart failure had higher mortality, more in-hospital complications, and longer hospitalizations. At 1-year follow up, 21% of the patients in whom congestive heart failure developed had died versus 5% in the group without congestive heart failure. Predictors of new congestive heart failure included increased age, anterior wall myocardial infarction, lower pulse pressure and systolic blood pressure, diabetes mellitus, and the presence of rales on admission. The acute angiographic variables of reduced ejection fraction, increased number of diseased vessels, and attempted percutaneous intervention improved the concordance of the predictive model by 6%. Congestive heart failure remains a common clinical problem after acute myocardial infarction and is associated with a twofold increase in in-hospital morbidity and a fourfold increase in in-hospital and 1-year mortality. The development of congestive heart failure in the hospital can be predicted from noninvasive and invasive baseline characteristics. We present a simple table to predict congestive heart failure from baseline characteristics and invasive information.

Bilateral renal artery occlusion: an unusual presentation of atrial fibrillation and hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy predisposes patients to atrial fibrillation and the development of systemic embolization. We describe a rare case of bilateral renal artery thrombosis which presented as acute renal failure requiring dialysis. The patient was successfully treated with a selective, continuous infusion of urokinase which resulted in the return of adequate renal function.

Clinical importance of thrombocytopenia occurring in the hospital phase after administration of thrombolytic therapy for acute myocardial infarction. The Thrombolysis and Angioplasty in Myocardial Infarction Study Group

OBJECTIVES

The purpose of this study was to examine the incidence and clinical implications of thrombocytopenia that occurs in hospital after administration of thrombolytic therapy for acute myocardial infarction.

BACKGROUND

The use of thrombolytic therapy in patients with acute myocardial infarction has improved mortaltiy rates, but hemorrhage remains a major complication. Because thrombocytopenia may be associated with hemorrhage after thrombolytic therapy, we examined the incidence and clinical implications of thrombocytopenia after administration of thrombolytic therapy for acute myocardial infarction.

METHODS

The patient population comprised 1,001 patients enrolled in Phases 2, 3 and 5 of the Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) trial and the urokinase trial. Patients received recombinant tissue-type plasminogen activator, urokinase or combination therapy in various dosing schemes. All patients received heparin, aspirin and a calcium-channel blocking agent. Thrombocytopenia occurring anytime after thrombolytic therapy was defined as a nadir platelet count either < 100,000/microliters or < 1/2 baseline. Blood loss was quantified by a bleeding index. Multiple logistic regression was used to evaluate the independent contribution of thrombocytopenia in a model predicting in-hospital mortality.

RESULTS

Thrombocytopenia occurred in 16.4% of patients, with no difference among the thrombolytic regimens. Patients with thrombocytopenia had a lower median acute ejection fraction and a higher likelihood of three-vessel coronary artery disease than patients without thrombocytopenia. Patients with thrombocytopenia had more hemorrhage, a higher in-hospital mortality rate and a more complicated hospital course than patients without thrombocytopenia, even after consideration of other important variables, including age, acute ejection fraction, number of diseased vessels, bypass surgery and use of intraaortic balloon counterpulsation.

CONCLUSIONS

Thrombocytopenia after thrombolytic therapy is a common event and is associated with excess hemorrhage and mortality. Platelet counts should be monitored daily after administration of thrombolytic therapy because the appearance of thrombocytopenia identifies a subset of patients at increased risk for hemorrhage and death.

Successful prolonged local infusion of urokinase for the hypothenar hammer syndrome

Ulnar artery thrombosis secondary to trauma, also known as the hypothenar hammer syndrome, has been most commonly been treated by surgical techniques. Applying concepts of local lysis of thrombotic occlusion used in cardiac and peripheral vascular intervention, we describe a method of correction of the hypothenar hammer syndrome by prolonged urokinase infusion.

Minimizing the risk of inappropriately administering thrombolytic therapy (Thrombolysis and Angioplasty in Myocardial Infarction [TAMI] study group)

Despite the proven benefits of thrombolytic therapy in acute myocardial infarction, concern for its complications, especially in patients misdiagnosed with myocardial infarction, has led to hesitancy in its use. Historical, clinical and electrocardiographic criteria were developed for enrolling patients with suspected acute myocardial infarction into thrombolytic trials by noncardiovascular specialists. The incidence of misdiagnosis of myocardial infarction and the clinical outcomes when these criteria were used were evaluated for 1,387 consecutive patients given thrombolytic therapy. Twenty-five community hospitals and 7 interventional centers were the sites of enrollment. Most patients (63%) were enrolled from community hospitals. Criteria for thrombolytic therapy included: symptoms of acute myocardial infarction < 6 hours but > 20 minutes, and not relieved by nitroglycerin; and ST-segment elevation > or = 1 mm in 2 contiguous leads or ST-segment depression of posterior myocardial infarction. Exclusion criteria reflecting increased risk of bleeding were used. A final diagnosis of myocardial infarction was based on creatinine kinase-MB, electrocardiographic and ventriculographic evaluation. Acute myocardial infarction was misdiagnosed in 20 patients (1.4%; 95% confidence interval 0.8-2.0%). These patients were demographically similar to those with acute myocardial infarction. All misdiagnosed patients survived; no significant adverse events occurred. Thus, in several clinical settings, a simple algorithm with specific criteria was used for diagnosing acute myocardial infarction and administering thrombolytic therapy. The inclusion criteria used in this study led to a low rate of misdiagnosis.

Intracoronary stenting compared with conventional therapy for abrupt vessel closure complicating coronary angioplasty: a matched case-control study

OBJECTIVES

A case-control analysis was performed to compare clinical outcome after intracoronary stenting with that after conventional therapy for abrupt vessel closure.

BACKGROUND

Previous studies have demonstrated that stenting after abrupt vessel closure results in marked angiographic improvement and preservation of coronary flow, leading to the anticipation of similar improvement in clinical outcome.

METHODS

Sixty-one of 92 consecutive patients treated at two clinical sites by intracoronary stenting for abrupt vessel closure were matched, according to angiographic features of closure and estimated left ventricular mass threatened by ischemia, with patients treated conventionally during the 18 months before stent availability. In 33 pairs of matched patients, vessel closure was established; in 28 pairs, it was threatened (coronary dissection or worsening stenosis with preservation of normal anterograde flow). Baseline clinical and angiographic characteristics were comparable in the two matched groups. Patients with indeterminate mechanisms of total occlusion (31%) or dissections < 15 mm long (43%) predominated; patients with visible thrombus (8%) or dissections > 15 mm long (18%) were infrequently represented. Stents were successfully deployed in 60 of 61 patients at a median of 52 min (range 3 to 269) after the onset of closure.

RESULTS

When compared with conventional treatment, stenting resulted in less residual stenosis (26% vs. 49% diameter stenosis, p < 0.001), a greater likelihood of restoration of Thrombolysis in Myocardial Infarction (TIMI) grade 3 blood flow (97% vs. 72%, p < 0.001) and a reduction in the need for emergency bypass surgery (4.9% vs. 18%, p = 0.02). However, the incidence of Q wave myocardial infarction was nearly the same in the two groups (32% vs. 20%, respectively, p = NS). In the group with stenting, peak creatine kinase level and the frequency of Q wave infarction after established vessel closure increased with the time to stent placement (p = 0.001 and 0.054, respectively); the incidence of procedure-related Q wave infarction in patients who underwent stenting within 45 min of closure was very low (3.9%). In-hospital death occurred in 3.3% of patients in each treatment group. At a mean of 6.3 months of follow-up after hospital discharge, survival free from late cardiac death, myocardial infarction, bypass surgery or coronary angioplasty was 74.9% and 81.3% in the stent and the control treatment group, respectively (p = NS).

CONCLUSIONS

Although early treatment of established vessel closure by intracoronary stenting was associated with a low incidence of both myocardial infarction and emergency bypass surgery, the likelihood or severity of infarction was not reduced among those in whom stents were implanted later. Patients with threatened vessel closure could not be shown to benefit from stent treatment. These data provide preliminary indications for stent placement in the acute period to be validated in larger randomized studies.

Thrombolytic therapy in patients requiring cardiopulmonary resuscitation

Cardiopulmonary resuscitation (CPR) is often considered a contraindication to thrombolytic therapy for acute myocardial infarction. Of 708 patients involved in the first 3 Thrombolysis and Angioplasty in Myocardial Infarction trials of lytic therapy for acute infarction, 59 patients required less than 10 minutes of CPR before receiving lytic therapy (CPR greater than 10 minutes was an exclusion of the trials) or required CPR within 6 hours of treatment. The patients receiving CPR were similar to the remainder of the group with respect to baseline demographics. The indication for CPR was usually ventricular fibrillation (73%) or ventricular tachycardia (24%). The median duration of CPR was 1 minute, with twenty-fifth and seventy-fifth percentiles of 1 and 5 minutes, respectively. The median number of cardioversions/defibrillations performed was 2 (twenty-fifth and seventy-fifth percentiles of 1 and 3 minutes, respectively). Patients receiving CPR were more likely to have anterior infarctions (66 vs 39%), the left anterior descending artery as the infarct-related artery (63 vs 38%) and lower ejection fractions on the initial ventriculogram (46 +/- 11 vs 52 +/- 12%) than those not receiving CPR. In-hospital mortality was 12 vs 6% with most deaths due to pump failure (57%) or arrhythmia (29%) in the CPR group and pump failure (38%) or reinfarction (25%) in the non-CPR group. At 7 day follow-up the CPR group had a significant increase in ejection fraction (+5 +/- 9%) compared with no change in non-CPR group. There were no bleeding complications directly attributed to CPR.(ABSTRACT TRUNCATED AT 250 WORDS)

Rapid thrombus dissolution by continuous infusion of urokinase through an intracoronary perfusion wire prior to and following PTCA: results in native coronaries and patent saphenous vein grafts

Even with aspirin and heparin therapy, thrombus present prior to or forming after percutaneous transluminal coronary angioplasty (PTCA) results in significant complications. We report on 33 patients who were treated with continuous infusion of Urokinase through an intracoronary perfusion wire for 24 hr because of visible intracoronary thrombus. Seventeen native vessels (9 pre-PTCA and 8 post-PTCA) and sixteen saphenous vein grafts (12 pre-PTCA and 4 post-PTCA) were treated. All vessels were patent at the time of perfusion wire placement. Complete thrombus resolution, successful PTCA and sustained patency was seen in 31 of 33 patients. One native vessel treated post PTCA (originally occluded) re-occluded. One saphenous vein graft treated prior to PTCA showed improvement in thrombus but distal embolization with balloon inflation occurred. No significant complications related to the intracoronary infusion technique were observed. In conclusion, rapid lysis of intra-coronary thrombus can be accomplish safely using this technique and can result in improved PTCA outcome.

Identification of acute myocardial infarction patients suitable for early hospital discharge after aggressive interventional therapy. Results from the Thrombolysis and Angioplasty in Acute Myocardial Infarction Registry

BACKGROUND

Very early (day 4) hospital discharge has recently been proposed for selected patients with acute myocardial infarction (MI). The purpose of this study was to determine the most useful factors for identifying acute MI patients treated with aggressive interventional therapy who could be safely discharged on day 4.

METHODS AND RESULTS

We studied 708 patients enrolled in the Thrombolysis and Angioplasty in Acute Myocardial Infarction trials I-III. Patients dying in the first 3 days and those with early (days 1-3) emergency coronary artery bypass graft surgery (CABG), late elective CABG (greater than or equal to day 4), or urgent/emergency CABG resulting from a late elective coronary angioplasty were excluded. The remaining 580 patients were randomly divided into a training sample (group 1) that was used to build a logistic regression model for predicting the absence of a late major complication and a test sample (group 2) that was used to validate this model. For this study, patients were considered appropriate for day 4 hospital discharge if they did not experience any of the following for 30 days after MI: death, reinfarction, cardiogenic shock, pulmonary edema, sustained hypotension, sustained ventricular tachycardia, high-grade atrioventricular block, acute ventricular septal defect, and recurrent ischemia necessitating urgent CABG. In group 1, four variables were independent predictors of freedom from late major complications: absence of early sustained ventricular tachycardia or ventricular fibrillation, absence of early sustained hypotension or cardiogenic shock, fewer coronary arteries with significant (greater than or equal to 75%) stenosis, and a higher left ventricular ejection fraction. In group 2, 23% of patients had a logistic model prediction of a 3% or less chance of a late complication. These patients had no deaths or reinfarctions by day 30 and a 3% late major complication rate.

CONCLUSIONS

The results of early cardiac catheterization and the absence of selected early (days 1-3) major complications do allow identification of a low risk subgroup of acute MI patients that may be suitable for very early discharge.

The use of intraaortic balloon pumping as an adjunct to reperfusion therapy in acute myocardial infarction. The Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) Study Group

To assess the risk and possible benefits of use of the percutaneous IABP in patients given thrombolytic therapy as treatment for acute myocardial infarction, we prospectively evaluated 810 consecutive patients entered into the TAMI trials. During hospitalization the 85 patients treated with the IABP had more cardiac risk factors, were slightly older (58 vs 56 years), and more often had anterior infarction (62% vs 38%). At acute cardiac catheterization, patients treated with the IABP also had more multivessel coronary disease (67% vs 43%), more frequent TIMI grade 0 or 1 flow (44% vs 28%), lower global ejection fraction (40% vs 52%), and worse regional infarct (-3.2 vs -2.5 SD/chord) and noninfarct (-0.67 vs +0.36 SD/chord) zone function. Although mortality rates (32% vs 4%) and in-hospital complications were greater in patients treated with the IABP, a greater improvement in global (delta ejection fraction: +1.9% vs +0.7%) and noninfarct zone (delta SD/chord: +0.11 vs -0.09) left ventricular function was observed in patients treated with the IABP at 1-week follow-up angiography. In addition, no reinfarction or reocclusion of the infarct-related artery occurred while patients were being treated with the IABP. These results suggest that the IABP may have a specific role after thrombolytic therapy in treating patients at high risk for reocclusion or at high risk for hemodynamic deterioration because of large infarction or critical stenoses in coronary vessels supplying the noninfarct zone.

Myocardial infarction with minimal coronary atherosclerosis in the era of thrombolytic reperfusion. The Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) Study Group

The incidence of minimal residual atherosclerotic coronary obstruction after successful intravenous thrombolytic therapy was evaluated in 799 patients with acute myocardial infarction. Minimal residual coronary obstruction (less than or equal to 50%) was observed on selective coronary angiography performed 90 min after initiation of thrombolytic therapy in 43 patients (5.5%). In 42 other patients (5.4%), a greater than 50% but less than 100% residual stenosis noted at 90 min demonstrated further resolution of obstruction to less than 50% at an angiographic follow-up study 7 to 10 days later. Patients with minimal residual coronary obstruction were significantly younger (52 +/- 10.7 versus 56.7 +/- 10 years; p = 0.002) and had less multivessel coronary disease (p less than 0.001), better initial left ventricular ejection fraction (54 +/- 12% versus 50.2 +/- 11.4%; p = 0.006) and a lower in-hospital mortality rate (1% versus 7%; p = 0.04) than did patients who had a significant (greater than 50%) residual coronary obstruction after intravenous thrombolysis. Long-term follow-up study of patients with a minimal coronary lesion (average 1.5 +/- 0.6 years) and those with significant residual stenosis (average 1.6 +/- 0.7 years) demonstrated that the incidence of death (2.4% in patients with minimal stenosis versus 3.5% in those with significant stenosis) and recurrent myocardial infarction (5% each) were similar in both groups. New strategies are needed to prevent coronary rethrombosis in patients with minimal atherosclerosis after thrombolytic therapy for acute myocardial infarction.

Fate of patients with acute myocardial infarction with patency of the infarct-related vessel achieved with successful thrombolysis versus rescue angioplasty

Patients with failure of infarct-related artery recanalization after thrombolytic therapy have a poor clinical outcome. These patients have been considered for rescue angioplasty 90 min after thrombolytic therapy at the time of emergency catheterization in the course of five Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) trials. The outcome of 776 patients with patent infarct-related vessels after emergency catheterization was analyzed--607 with thrombolysis-mediated patency of the infarct-related vessel and 169 with patency achieved by angioplasty. Baseline characteristics of the thrombolysis and angioplasty patency groups were similar except for a higher acute left ventricular ejection fraction (51.3% versus 48.2%) in the thrombolysis group (p = 0.003). Seven to 10 day left ventricular ejection fraction was higher (52.3% versus 48.1%), infarct zone functional recovery was greater (0.44 versus 0.21 standard deviation/chord, or 18% versus 7%, p = 0.001) and reocclusion was less (11% versus 21%) in the thrombolysis compared with the angioplasty group. Despite these differences, angioplasty patency was associated with the same low in-hospital mortality rate (5.9% versus 4.6%) and long-term mortality rate (3% versus 2%) as thrombolysis patency. Reocclusion adversely affected the mortality rate and ventricular functional recovery. Technical failure of rescue angioplasty was associated with a much higher mortality rate than was technical success (39.1% versus 5.9%). Thrombolysis patency was preferable to angioplasty patency after thrombolytic therapy in acute myocardial infarction, but both were associated with the same low in-hospital and long-term mortality rates, suggesting that rescue angioplasty is beneficial in some patients with failure of infarct-related artery recanalization after thrombolytic therapy.

Stroke and acute myocardial infarction in the thrombolytic era: clinical correlates and long-term prognosis

Thirteen (1.8%) of 708 patients with acute myocardial infarction treated with recombinant tissue-type plasminogen activator in the Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) I, II and III trials developed a stroke. Four strokes were hemorrhagic and nine were nonhemorrhagic. Of five prespecified risk factors for intracranial hemorrhage (age greater than 65 years, history of hypertension, history of prior cerebrovascular disease, aspirin use and acute hypertension), two patients had two risk factors and one patient had one risk factor. However, 80% of patients without intracranial hemorrhage had at least one risk factor and 31% had two risk factors. No patient with a prior stroke or transient ischemic attack (all greater than 6 months previously) had an intracranial hemorrhage. Of three prespecified risk factors for nonhemorrhagic stroke (atrial fibrillation, prior cerebrovascular disease and large anterior wall infarction), only the occurrence of a large anterior myocardial infarction (with ejection fraction less than 45%) was a predictor (p = 0.0015). The in-hospital death rate was 25% for patients with hemorrhagic stroke versus 11% for patients with a non-hemorrhagic stroke and 6% for those patients without a stroke. Furthermore, the hospital stay was greater than 50% longer in patients who had a stroke than in those who did not. Thus, intracranial hemorrhage remains an unpredictable risk in patients treated with thrombolytic therapy and cerebral infarction is related to anterior myocardial infarction and poor left ventricular function. Both types of stroke are associated with substantial morbidity and mortality.

Brachial approach to emergency cardiac catheterization during thrombolytic therapy for acute myocardial infarction. TAMI Study Group

The use of the brachial approach to acute coronary intervention has not been previously studied. In the course of the Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) trials, we used the transbrachial approach to cardiac catheterization with or without angioplasty in 202 of 704 (28.6%) patients. The baseline characteristics of age, sex, risk factors, medical history, time from symptom onset to therapy, and left ventricular function were similar for the 2 different approaches. Time from therapy to coronary angiography was not delayed by the brachial approach compared with the femoral approach: 97.1 +/- 26 min vs. 99.9 +/- 133.8 min, respectively. Chemical patency was established in 78 vs. 73% of patients and technical success with acute PTCA with the brachial approach was 89% vs. 78% with the femoral approach. Clinical outcomes were quite similar with respect to death (6 vs. 6%), reocclusion (10 vs. 14%), and emergency coronary bypass surgery (5 vs. 6%). Baseline hematocrit was 43.9 +/- 4.4 and 43.5 +/- 4.8, respectively with a nadir of 32.9 +/- 5.6 vs. 33.0 +/- 5.4. The need for vascular repair occurred in 1% vs. 3% of patients and retroperitoneal hemorrhage was documented in 1% vs. 1% of patients. This study indicates that in the hands of experienced operators the transbrachial approach to acute coronary intervention in the acute phase of treatment with thrombolytic therapy can be used with equal risks and efficacy as the femoral approach.

Complex coronary angioplasty: use of a new microprobe balloon catheter

Since the introduction of coronary angioplasty by Gruntzig et al. (Circulation [Suppl II] 56:84, 1977), a key determinant to overall success has been advancement in equipment technology. Major advances have been made in the availability of low-profile catheters in the last 5 years that have facilitated penetration of high-grade distal and complex lesions. The USCl probe TM catheter is an example of a low-profile catheter that has shown favorable applicability in dilating high-grade stenoses. Preliminary data indicate that this device has good trackability and an extremely low profile, which allows penetration of stenoses where other current low-profile catheters have failed.

Combined tissue-type plasminogen activator and prostacyclin therapy for acute myocardial infarction. Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) 4 Study Group

Current limitations of recombinant tissue-type plasminogen activator (rt-PA) therapy for acute myocardial infarction include failure to achieve recanalization in 25% of patients, reocclusion and reperfusion injury. Iloprost, a stable analogue of prostacyclin (PGI2), has been demonstrated to facilitate thrombolysis and reduce myocardial stunning in experimental models. To evaluate combined therapy, rt-PA (100 mg 3 h) and Iloprost (2 ng/kg per min for 48 h) were administered to 25 patients and then rt-PA alone (same dose) was given to an additional 25 patients with evolving myocardial infarction. At 90 min after drug administration, infarct-related vessel patency was observed in 11 (44%) of 25 who received rt-PA plus Iloprost compared with 15 (60%) of 25 who received rt-PA alone (p = 0.26). At 1 week, reocclusion had occurred in 3 (14%) of 21 patients who received combined therapy compared with 6 (26%) of 23 patients treated with rt-PA alone (p = 0.46). Ejection fraction increased significantly from baseline to 7 days for rt-PA alone whereas it decreased with combined therapy (rt-PA alone whereas it decreased with combined therapy (rt-PA alone: 47.3 +/- 11.5% at baseline to 50.4 +/- 9.8% at 7 days; rt-PA plus Iloprost: 51.3 +/- 10.1% at baseline to 49.0 +/- 9.4% at 7 days; difference between groups p = 0.05). At 4 h after therapy, fibrinogen decreased 33% for rt-PA plus Iloprost compared with a 52% for rt-PA alone (p = 0.001). Fibrinogen degradation products increased 60% more for rt-PA alone than for rt-PA plus Ilprost. Thus, the combination of rt-PA plus Iloprost at the doses employed did not improve immediate or follow-up coronary artery patency or left ventricular functional recovery compared with that achieved with rt-PA alone.

Favorable early and long-term prognosis following coronary bypass surgery therapy for myocardial infarction: results of a multicenter trial. TAMI Study Group

Coronary bypass surgery was performed before hospital discharge on 82 (21%) of 386 consecutive patients enrolled in the Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) multicenter trial of intravenous tissue plasminogen activator and coronary angioplasty for acute myocardial infarction. Time from infarct symptom onset to coronary bypass surgery was 7.3 +/- 1.9 hours for 24 patients operated upon on an emergency basis and 9.3 +/- 5.2 days for 58 patients having late in-hospital surgery. There were no operative deaths and five in-hospital deaths in the surgical group, all of which occurred in patients with preoperative cardiogenic shock. Although patients in the surgical group were older (59.7 +/- 10.4 years versus 54.9 +/- 10.2 years; p = 0.03), had more extensive coronary artery disease (42% three-vessel disease versus 11%; p = 0.001), and had a higher incidence of anterior wall myocardial infarction (48% versus 39%; p = 0.02), in-hospital mortality for the surgical group (6%) was similar to that in 301 patients not undergoing surgery (7%) in this trial. For patients discharged from the hospital, mortality at 1 year was 2.5% in the surgical group and 1.8% in patients not having coronary bypass surgery before hospital discharge. At a 1 year follow-up, there were no significant differences in the frequency of cardiac or noncardiac-related hospitalizations or in event-free survival between surgical and nonsurgical groups. The majority of patients in both groups considered themselves to be in excellent or good condition. Coronary bypass surgery can be performed with low morbidity and mortality rates in close temporal association to acute myocardial infarction.(ABSTRACT TRUNCATED AT 250 WORDS)

A randomized controlled trial of intravenous tissue plasminogen activator and early intravenous heparin in acute myocardial infarction

To evaluate the coronary thrombolytic efficacy of tissue plasminogen activator (t-PA) and early intravenous heparin, 134 patients with acute myocardial infarction were randomly assigned to combination therapy or t-PA only. At a median of 2.78 hours from symptom onset, 64 patients received both t-PA (1.5 mg/kg/4 hr) and a bolus of 10,000 units heparin, whereas 70 patients received t-PA alone at the same dose. All patients underwent coronary angiography 90 minutes after initiation of therapy to determine infarct vessel patency status, after which time the control group patients were eligible to receive heparin. Baseline demographic and angiographic characteristics were similar for the groups. Infarct vessel patency was 50 of 63 (79%) for combination t-PA and heparin and 54 of 68 (79%) for t-PA alone. Bleeding complications, as reflected by need for transfusion, were similar in the two groups: 13% in the patients treated with t-PA and heparin compared with 18% in patients treated with t-PA only (p = 0.53). The only intracranial hemorrhage in the trial occurred in a patient initially treated without heparin. Fibrinogen at 50 minutes after therapy was 32% decreased from baseline for the t-PA and heparin-treated patients compared with a 39% decrease in the control group. Predischarge left ventricular ejection fraction was similar for the two groups: 49.0 +/- 10.1% versus 50.2 +/- 11.9% for combined versus t-PA only therapy, respectively. We conclude that early intravenous heparin does not facilitate the fibrinolytic effect of t-PA at the doses tested.(ABSTRACT TRUNCATED AT 250 WORDS)

Thrombolysis and Angioplasty in Myocardial Infarction (TAMI-1) trial: influence of infarct location on arterial patency, left ventricular function and mortality

The influence of infarct location on arterial patency, left ventricular function and mortality after 150 mg of intravenous recombinant tissue-type plasminogen activator (rt-PA) and selective coronary angioplasty was studied in 386 patients with acute myocardial infarction. In 329 patients with acute and 1 week angiograms, the 90 min infarct-related artery patency rate after rt-PA in the left anterior descending, the left circumflex and the right coronary artery was 77, 68 and 68%, respectively. Angioplasty, performed in half the patients, resulted in a final acute patency rate of 93%, which was not related to arterial distribution. Repeat catheterization and revascularization were required in 12% of patients before day 7 and were independent of arterial distribution. The reocclusion rate for the right coronary artery (21%) was higher than that for the left anterior descending (12%) or left circumflex (5%) artery (p = 0.01). Acute and 1 week contrast ventriculograms suitable for analysis were available in 266 patients. Whereas serial left ventricular ejection fraction did not improve during the course of this study, serial regional wall motion (centerline chord method) improved in each arterial distribution. The in-hospital mortality rate of 6% was not related to arterial distribution, although death was twice as likely with proximal compared with distal lesions. Ten of 11 patients who died in the group with the left anterior descending artery as the infarct-related artery had a lesion proximal to the first septal perforator branch.(ABSTRACT TRUNCATED AT 250 WORDS)

Failure of simple clinical measurements to predict perfusion status after intravenous thrombolysis

To determine whether coronary patency could be detected early during thrombolytic therapy, commonly used markers of perfusion were recorded in 386 patients with acute myocardial infarction treated with tissue plasminogen activator. Infarct artery angiography 90 minutes after initiation of therapy was used to determine perfusion status. Of patients with complete resolution of ST segment elevation before the angiogram, 96% (95% confidence interval, 79% to 100%) showed perfusion on the angiogram, and among those with partial improvement, 84% (95% confidence interval, 76% to 90%) showed perfusion, but these findings occurred in only 6% and 38% of patients respectively. When complete resolution of chest pain occurred before the angiogram, 84% of patients (95% confidence interval, 75% to 90%) showed perfusion, but this finding occurred in only 29% of patients. Although arrhythmias occurred frequently in the first 90 minutes of therapy, none were associated with a higher patency rate. No other factors predicted coronary patency. A logistic regression model showed 25% of patients with 90% or greater probability of patency, but 56% of patients with no ST segment or symptom resolution had patent arteries.

Characteristics and outcome of patients in whom reperfusion with intravenous tissue-type plasminogen activator fails: results of the Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) I trial

To examine the outcome of patients with persistent coronary artery occlusion despite treatment with intravenous tissue-type plasminogen activator (t-PA), the clinical course of 96 patients with persistent occlusion after 90 min of therapy was evaluated. All patients underwent cardiac catheterization 90 min after initiation of intravenous t-PA. Immediate coronary angioplasty (PTCA) was attempted when the infarct-related artery failed to reperfuse unless the vessel was technically unsuitable or the infarct was thought to be small. No baseline differences could be found between these 96 patients and 288 patients who achieved perfusion with the same protocol. Although patients with and without successful perfusion after t-PA had similar clinical courses before cardiac catheterization, those without perfusion had more complications (ventricular fibrillation, severe bradycardia, hypotension) during catheterization. PTCA achieved reperfusion with less than 50% residual stenosis in 73% of the 86 patients in whom it was attempted, while 16% were left with a high-grade (greater than 50%) residual stenosis and PTCA failed in 11%. Mortality was highest in the nine patients with complete PTCA failure (44%), compared with a 6% mortality in the 63 patients with an insignificant residual stenosis after PTCA and a 14% mortality in the 14 patients with reperfusion, but a greater than 50% residual stenosis after PTCA. In 10 patients with small infarcts (six), unsuitable anatomy (two), or "spontaneous" drug induced (but later) opening before contemplated PTCA (two), PTCA was not attempted and no mortality occurred. The in-hospital reocclusion rate after successful PTCA was 29%, despite the use of heparin and antiplatelet agents.(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary arterial thrombolysis with combined infusion of recombinant tissue-type plasminogen activator and urokinase in patients with acute myocardial infarction

To determine whether tissue-type plasminogen activator (t-PA) and urokinase (UK) act synergistically to achieve coronary thrombolysis, incremental doses of both drugs were infused intravenously over 60 min. In 146 consecutive patients treated 3.0 +/- 1.0 hr from symptom onset, coronary angiography was performed 90 min after the start of the infusion and at 7 days. The groups of patients treated by different dose regimen were as follows: group I, 14 patients treated with t-PA 25 mg and UK 0.5 million U; group II, 20 patients given t-PA 25 mg and UK 1.0 million U; group III, 24 patients given t-PA 1.0 mg/kg and UK 0.5 million U; group IV, 33 patients treated with t-PA 1.0 mg/kg and UK 1.0 million U; and group V, 55 patients given t-PA 1.0 mg/kg and UK 2.0 million U. In groups I and II, patency of the infarct-related vessel at 90 min was only 36% and 42%, respectively. With 1 mg/kg t-PA and increasing doses of UK (groups III to V), patency ranged from 72% to 75% (overall 73%). Repeat catheterization at 7 days demonstrated reocclusion in groups III to V in 10 of 110 (9%). The patency and reocclusion rates in groups III to V were not significantly different from those in our previous study of 386 patients treated with t-PA alone (150 mg over 6 to 8 hr). In that study the patency rate of the infarct-related vessel at 90 min was 75% (p = .66) and reocclusion occurred in 15% (p = .11).(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of two dose regimens of intravenous tissue plasminogen activator for acute myocardial infarction

Two dosing schedules of intravenous tissue plasminogen activator (t-PA) for acute myocardial infarction were compared in a multicenter trial. At 2.95 +/- 1.1 hours from onset of chest pain, 386 patients received 150 mg of intravenous t-PA. For the first 178 patients (group A), 60 mg were given in the first-hour dose and the remaining 90 mg were infused over 7 hours. In the subsequent 208 patients (group B), the first-hour dose was 1.0 mg/kg and the remaining 150 mg were given over 5 hours. At initial angiography 94 +/- 30 minutes into therapy, the infarct vessel patency was 64% in group A versus 75% in group B (p = 0.02). By final angiography with up to 4 selective contrast injections, patency was 68% versus 77%, respectively (p = 0.06). Repeat angiography at 7 to 10 days demonstrated reocclusion in 17% of group A and 13% of group B patients (p = 0.35). There was no difference in fibrinogen nadir or mean hematocrit drop between the 2 groups: 120 mg/dl and 11 points, respectively, in group A compared with 120 mg/dl and 10 points in group B. However, bleeding was reduced in group B patients as evident by a decrease in requirement for greater than or equal to 2 units of packed red blood cell transfusion (group A 36%, group B 27%, p = 0.05) and lower incidence of gastrointestinal bleeding (group A 12%, group B 4%, p = 0.002). To further study the importance of weight adjustment, patients were divided into 2 groups according to weight (less than or equal to 90 kg versus greater than 90 kg).(ABSTRACT TRUNCATED AT 250 WORDS)

A randomized trial of immediate versus delayed elective angioplasty after intravenous tissue plasminogen activator in acute myocardial infarction

We compared the efficacy of immediate coronary angioplasty after acute myocardial infarction with that of elective angioplasty at 7 to 10 days in patients treated initially with intravenous tissue plasminogen activator. The plasminogen activator (150 mg) was administered 2.95 +/- 1.1 hours after the onset of symptoms, to 386 patients with acute myocardial infarction. Ninety minutes later, patency of the coronary artery serving the area of the infarct was demonstrated by coronary angiography in 288 patients (75 percent). Bleeding problems were frequently encountered, as evidenced by an average drop in hematocrit of 11.7 +/- 6.5 points from base line to nadir and by a need for transfusion not related to bypass surgery in 70 patients (18 percent). After successful thrombolysis, 197 patients with a patent but severely stenotic vessel suitable for angioplasty were randomly assigned to immediate angioplasty (n = 99) or, if indicated 7 to 10 days after infarction, to deferred (elective) angioplasty (n = 98). The incidence of reocclusion was similar in the two groups: 11 percent in the group assigned to immediate angioplasty and 13 percent in the group assigned to elective angioplasty. Neither group had a significant improvement in global left ventricular function, and regional wall motion in the infarct zone improved to a similar extent in the two groups. In the elective-angioplasty group, the rate of crossover to emergency angioplasty for recurrent ischemia was 16 percent (whereas 5 percent of the immediate-angioplasty group required emergency repeated angioplasty; P = 0.01). In 14 percent of the patients in the elective group, the stenosis was substantially reduced by the time of the seven-day follow-up angiography, obviating the need for angioplasty. We conclude that in patients with initially successful thrombolysis and suitable coronary-artery anatomy, immediate angioplasty offers no clear advantage over delayed elective angioplasty.