A difference between front-loaded streptokinase and standard-dose recombinant tissue-type plasminogen activator in preserving left ventricular function after acute myocardial infarction (the Central Illinois Thrombolytic Therapy Study).

A blinded, randomized trial compared the effects of front-loaded streptokinase with those of the conventional dose of intravenous recombinant tissue-type plasminogen activator (rt-PA) on left ventricular (LV) function after acute myocardial infarction (AMI). Thrombolytic therapy was administered in the emergency departments of 30 community hospitals in central Illinois, and subsequent studies were performed at 1 tertiary referral center. Patients aged < or = 75 years with a first AMI who could be treated within 4 hours of the onset of chest pain were randomly assigned to receive either streptokinase (375,000 IU bolus, followed by 1,125,000 IU over 1 hour) or rt-PA (10 mg bolus, followed by 50 mg in the first hour, and 20 mg/hour for the next 2 hours). All patients were treated with aspirin (325 mg) and intravenous heparin. Patients were transferred for angiography within 24 hours. During the 30-month study, 253 patients were treated with intravenous thrombolytic therapy 2.4 +/- 1.0 hour after the onset of AMI. In patients with anterior wall AMI (n = 90), global LV ejection fraction measured by angiography within 24 hours was 45 +/- 12% with rt-PA, and 39 +/- 13% with streptokinase (p < 0.03). Convalescent radionuclide angiography documented a persistent beneficial effect of rt-PA on LV regional wall contractility, but not global ejection fraction. There were no differences between rt-PA and streptokinase in preserving global or regional LV function in patients with inferior wall AMI.

Nephrotoxicity of nonionic low-osmolality versus ionic high-osmolality contrast media: a prospective double-blind randomized comparison in human beings.

To test whether a nonionic, low-osmolality contrast medium (iopamidol) administered for coronary angiography was less harmful to renal function than ionic, high-osmolality medium (sodium diatrizoate), a prospective, double-blind randomized study of 70 patients with normal or mildly depressed renal function (serum creatinine < or = 2.0 mg/dL (175 mumol/L) was performed. Creatinine clearance was determined before coronary angiography and 24 and 48 hours after. There were no significant differences between the low- and high-osmolality groups with regard to age, baseline creatinine clearance, or dose of contrast medium given. In patients receiving low-osmolality medium (n = 35), creatinine clearance decreased by 19% +/- 13 (1 standard deviation) at 24 hours and recovered by 48 hours. In patients receiving high-osmolality medium (n = 35), creatinine clearance decreased by 40% +/- 16 at 24 hours and remained depressed by 47% +/- 14 at 48 hours. In patients with normal or mildly depressed renal function, use of a non-ionic, low-osmolality contrast medium minimized nephrotoxicity as measured by reductions in creatinine clearance after coronary angiography.

Six-year survival after coronary thrombolysis and early revascularization for acute myocardial infarction.

Six-year follow-up was conducted in a consecutive series of 192 patients receiving thrombolytic therapy for acute myocardial infarction (AMI) with ST-segment elevation. Cardiac catheterization was performed within a day, and patients with an open infarct artery routinely had early revascularization: 99 (67%) underwent coronary bypass surgery and 18 (12%) coronary angioplasty. With this treatment strategy, 6-year cardiac mortality was 14.5%, 6% (12 patients) in hospital and 9% (16 patients) for survivors of hospitalization. Multivariate analysis showed that predictors of cardiac death among survivors of hospitalization were a closed infarct artery at catheterization (p less than 0.01), diabetes (p less than 0.01) and anterior myocardial infarction (p = 0.01). A subset of 146 patients underwent radionuclide angiography before hospital discharge; for them, predictors of mortality were a closed infarct artery at catheterization (p less than 0.01), anterior wall AMI (p = 0.02), and Killip class III to IV on admission (p less than 0.06). Left ventricular ejection fraction was not a significant predictor of mortality for this subset of patients.

Determinants of hospital charges for coronary artery bypass surgery: the economic consequences of postoperative complications.

This is a prospective study of 500 consecutive patients having coronary artery bypass surgery; mean hospital charge from time of surgery to discharge was +11,900 +/- 12,700. Multiple regression analysis was performed using preoperative variables and postoperative complications. No preoperative clinical feature was a significant predictor of higher average charge. Sternal wound infection (p = 0.0001), respiratory failure (p = 0.0001) and left ventricular failure (p = 0.017) were associated with higher average hospital charge. The absence of any complication predicted a lower average charge, and postoperative death (4.4 +/- 4.5 days after surgery) was also associated with lower average charge. A cost equation was developed: hospital charge equalled $11,217 + $41,559 of sternal wound infection, + $28,756 for respiratory failure, + $5,186 for left ventricular failure, - $1,798 for no complication and - $6,019 for death. Recognition of the influence of complications on charges suggests that low average charges can only be achieved by surgical programs with a low complication rate.

The primary care physician and thrombolytic therapy for acute myocardial infarction: comparison of intravenous streptokinase in community hospitals and the tertiary referral center.

From September 1982 through December 1987, 1012 patients were treated with intravenous streptokinase within 6 hours of acute myocardial infarction. Most of them (816/1012, 81 percent) were treated in community hospitals by primary care physicians. The remaining 196 (19 percent) were treated in the referral center, usually by a cardiologist. Cardiac catheterization within 2 days showed an open infarct artery in 87 percent of the community hospital and 83 percent of the referral center patients (P = NS). Predischarge ejection fraction was similar for community hospital and referral center patients (49 percent +/- 14 percent versus 51 percent +/- 14 percent, respectively), and there was a similar rate of bleeding complications (10 percent versus 13 percent, respectively). We conclude that primary physicians can use intravenous streptokinase effectively and safely in the treatment of patients in community hospitals.

Early and late results of operation after thrombolytic therapy for acute myocardial infarction.

Recent reports have established the efficacy of thrombolytic therapy in limiting myocardial infarction. Between September 1981 and September 1984, 355 patients were treated with intracoronary (87) or intravenous (268) streptokinase within 6 hours of acute myocardial infarction. Thrombolysis was successful in 63% of patients receiving intracoronary streptokinase and 81% of those receiving intravenous streptokinase. Because residual critical stenosis is usually present and predisposes the patient to reinfarction, revascularization procedures were investigated as an extension of thrombolytic therapy. One hundred ninety-one patients aged 56 +/- 10 (25 to 77) years underwent early surgical revascularization 4.1 +/- 3.6 days after intracoronary or intravenous streptokinase for acute myocardial infarction. Results of this treatment were successful in 89% (170/191) of the patients. Thirteen patients (6.8%) underwent emergency coronary artery bypass grafting for failed percutaneous angioplasty. There were 3.2 +/- 1.4 grafts per patient and 3.8 +/- 2.9 units of blood were administered in the perioperative period. Operative mortality was 4.2% (8/191) with a 15.4% mortality (2/13) in the group in which angioplasty failed. Mean hospitalization time after operation was 10.9 +/- 6.8 days. Follow-up was 27 +/- 8 (12 to 48) months and was obtained on all patients. Late cardiac mortality was 1.0% (2/183). Ninety percent of the follow-up group was without angina and only 1.7% showed no improvement after operation. Reinfarction occurred in four patients (2.2%), with graft failure documented by coronary arteriography in two of these patients. This experience indicates that early revascularization after thrombolytic therapy may be performed with low operative mortality and morbidity and is associated with excellent late results.

Thrombolytic therapy followed by early revascularization for acute myocardial infarction.

During a 24-month period, 192 patients with acute myocardial infarction were treated with intracoronary or intravenous streptokinase (SK). In 147 patients (77%) an open infarct artery was demonstrated by coronary angiography; 117 of these 147 patients were judged to have viable myocardium supplied by a critically narrowed coronary artery and underwent revascularization 3 +/- 2 days after SK therapy. In-hospital mortality was 6% (12 of 192). The mortality rate over the subsequent 20 +/- 7 months of follow-up was lower for those in whom SK therapy was successful (1 of 137, 0.7%) than in those in whom it was not (6 of 43, 14%) (p less than 0.001), and tended to be lower for those treated with intravenous (2 of 111, 2%) rather than intracoronary SK (5 of 69, 7%, p = 0.11). Reinfarction occurred in 3% of the 180 survivors of hospitalization, angina pectoris in 11% and congestive heart failure in 7%. Clinical outcome was similar for patients treated with intravenous and intracoronary SK and for patients treated in community hospitals and the referral center.

Percutaneous transluminal coronary angioplasty as palliation for patients considered poor surgical candidates.

Thirty-one patients with angina inadequately controlled by medical therapy, but who were poor surgical candidates because of advanced age and poor general condition, or because of depressed left ventricular function, had percutaneous transluminal coronary angioplasty (PTCA). These high-risk patients were identified prospectively, and coronary artery bypass surgery (CABS) was planned only in the event of arterial occlusion and chest pain. PTCA was successful in 11 of 17 (65%) high-risk geriatric patients, in 11 of 12 (92%) patients with left ventricular ejection fraction less than 40%, and in two additional patients having PTCA without surgical stand-by because of technically difficult vascular anatomy for CABS. There were no PTCA-related deaths; three of the 31 high-risk patients had emergency surgery because of arterial occlusion, and the remaining four patients with PTCA failure remain on medical therapy for angina. The clinical course of the 31 high-risk patients was similar to that of 155 patients having PTCA during the study period who were considered good candidates for either PTCA or CABS. PTCA may thus be considered an intermediate, palliative procedure for patients with inadequate control of ischemic symptoms who are poor surgical candidates.

Reliability of Q-wave formation and QRS score in predicting regional and global left ventricular performance in acute myocardial infarction with successful reperfusion.

The frequency of electrocardiographic Q-wave formation and the relation of Q wave and QRS score to regional and global left ventricular (LV) performance were determined in 131 patients with acute myocardial infarction (AMI) receiving thrombolytic therapy. Thrombolytic therapy was successful in reperfusing the occluded infarct artery in 100 patients and was unsuccessful in 31. The number of patients who had 1 or more Q waves (88 vs 87%) and 2 or more Q waves (70 vs 74%) was similar. In contrast, normal wall motion was significantly more common in the infarct area in patients in whom reperfusion was successful (42 vs 15%, p less than 0.05). Total QRS scores were similar in patients in whom reperfusion was successful and in those in whom it was not (6.0 +/- 3.2 vs 6.4 +/- 4.2). Despite similar QRS scores, successfully treated patients had significantly higher LV ejection fraction (53 +/- 13% vs 46 +/- 15%, p less than 0.05). Thus, Q-wave formation after successful thrombolytic therapy for AMI is common but does not faithfully reflect regional or global LV performance. Electrocardiographic analysis alone is not a reliable method to assess efficacy of reperfusion therapy.

Transcutaneous pacemaker use in a large hospital.

For an eight-month period temporary transcutaneous and transvenous pacemaker use was analyzed in a 602-bed hospital which had readily available fluoroscopy. Twenty-four patients were treated with transcutaneous pacemaker; 23 of these were treated for asystole during cardiac arrest. The only patient not suffering cardiac arrest could not tolerate the transcutaneous pacemaker because of pain. Two of these 23 patients were treated early in the arrest with successful resuscitation. They became conscious and were able to tolerate the pacemaker well. Most of the other patients were treated late in the arrest with little chance of any therapy being successful. Only four of these 21 patients were treated within 15 minutes of the onset of cardiac arrest. During the same time span, 23 patients received transvenous temporary pacemakers. Only four of this group had suffered cardiac arrest before pacing. We conclude that: transcutaneous pacing can be successful but we did not find it useful when used late in a cardiac arrest; transvenous pacing seemed the approach most often chosen for the non-arrest situation.

Comparative cost of myocardial revascularization: percutaneous transluminal angioplasty and coronary artery bypass surgery.

A consecutive series of 78 patients having percutaneous transluminal coronary angioplasty for single vessel coronary artery disease and 85 patients having single vessel coronary artery bypass graft surgery were followed up prospectively for 1 year. Days in hospital and angiographic and revascularization procedures were counted in the two groups of patients and total cost of care for 12 months was calculated using current billing levels. Angioplasty was initially successful in 74% of patients; because of initial failure in 26% and late restenosis in 18%, bypass surgery was ultimately needed in 23 of 78 patients having coronary angioplasty. Nevertheless, total cost of care per patient was 43% lower for those having angioplasty as an initial procedure for single vessel coronary artery disease.

Early operative intervention after thrombolytic therapy for acute myocardial infarction.

Thrombolytic therapy effectively interrupts acute myocardial infarction but does not correct the underlying plaque causing acute thrombosis. Early operation and treatment of the residual coronary artery disease has therefore been evaluated. Over 29 months, 184 patients with acute myocardial infarction of less than 6 hours duration were treated with intracoronary (IC) or intravenous (IV) streptokinase (SK). Angiography was performed early and thrombolysis found to be successful in 70% of the IC-SK group and 82% of the IV-SK group. One hundred six patients with successful thrombolysis had early revascularization surgery performed 3.3 +/- 2.1 days following SK treatment (range 0 to 11 days). These patients were compared with 110 consecutive patients who underwent coronary artery bypass grafting for standard indications. The SK group had an average of 3.0 +/- 1.4 grafts, 4.3 +/- 3.1 units of blood, and 10.8 +/- 5.3 days in the hospital postoperatively per patient and had an operative mortality rate of 2.7%. The control group averaged 3.6 +/- 1.3 grafts, 4.0 +/- 2.4 units of blood, and 9.6 +/- 3.5 days in the hospital postoperatively per patient with an operative mortality rate of 2.7%. This experience indicates that early operation following SK therapy can be performed with low operative risk and without prolonged hospitalization.

Intravenous versus intracoronary streptokinase therapy for acute myocardial infarction in community hospitals.

A consecutive series of 184 patients with acute myocardial infarction (AMI) received thrombolytic therapy. The first 63 were treated in the catheterization laboratory with intracoronary streptokinase (IC-STK), and 44 (70%) had successful thrombolysis. One hundred twenty-one patients received intravenous (IV) STK immediately after diagnosis of AMI, and 99 (82%) were found to have an open infarct artery. Only 58% of patients (14 of 24) who required transfer from out-of-town hospitals for IC-STK treatment had successful thrombolysis; in contrast, IV-STK given in the local hospital resulted in an 85% (72 of 85) rate of thrombolysis (p = 0.005). IV-STK thus appears at least as effective as IC-STK for AMI and is more effective for patients treated in hospitals without catheterization facilities.