Suture closure of the femoral arteriotomy following invasive cardiac procedures: a detailed analysis of efficacy, complications, and the impact of early ambulation in 1,200 consecutive, unselected cases.

The purpose of this study was to assess the efficacy and safety of using a percutaneous suture device to close femoral arteriotomies following invasive cardiac procedures. All patients presenting for invasive cardiac procedures performed from the femoral artery were considered for suture closure. Patients were carefully assessed for access site complications, oozing, and the impact of suture closure on the safety of early ambulation. Clinical follow-up at 3-6 months was performed to assess for late complications. Femoral artery suture closures were performed in 1,200 consecutive cases in 1,097 patients. In 12.8% of cases, the patients ambulated within 1 hr. The success rate was 91.2% and the complication rate was 3.4%. Complications included the development of a hematoma (2.1%), the need for vascular surgery (0.6%), retroperitoneal hemorrhage (0.3%), blood transfusion (0.7%), local infection (0.5%), and pseudoaneurysm formation (0.1%). Factors found to be independently predictive of procedural failure were an age > 70 years, an ACT > 300 sec, left femoral artery access, and the performance of primary angioplasty. Follow-up at 3-6 months revealed no major hemorrhagic complications. We conclude that percutaneous suture closure effectively achieves femoral artery hemostasis in patients undergoing invasive cardiac procedures. The technique permits early ambulation and is associated with a relatively low incidence of complication.

Impact of end-stage renal disease on clinical and angiographic outcomes after coronary stenting.

Although patients with end-stage renal disease (ESRD) are at high risk for restenosis that requires repeat revascularization after balloon angioplasty, their restenosis rate after coronary stenting is still unknown. Over a 4-year period, we performed coronary stenting on 40 lesions in 34 patients with ESRD. We compared these lesions with 80 lesions from patients without renal disease who underwent coronary stenting in the STARS and WINS clinical trials, matched for treatment site, diabetes, lesion length, and reference vessel diameter. Quantitative coronary angiography was performed on all lesions and clinical outcomes were assessed at 9-month follow-up. Clinical and angiographic characteristics were well matched between the 2 groups and acute clinical success rates were similar. Despite comparable initial angiographic results over the 9-month follow-up period, repeat target lesion revascularization was twice as frequent in the ESRD group compared with the control group (35% vs 16%, p <0.05). After adjusting for differences in postprocedural minimum lumen diameter and other angiographic and clinical characteristics, ESRD remained the most important predictor of late target lesion revascularization (relative risk = 2.3, p = 0.04). In addition, overall 9-month mortality was higher for ESRD patients than for the control population (18% vs 2%, p <0.01). Thus, despite similar angiographic results, patients with ESRD are at higher risk for target lesion revascularization after coronary stenting than controls. Nonetheless, most patients with ESRD do not develop restenosis after stent placement, suggesting an important role for stenting in the management of this challenging population.

Synergy between intracoronary stenting and abciximab in improving angiographic and clinical outcomes of primary angioplasty in acute myocardial infarction.

This study examined 650 consecutive patients who presented with an acute myocardial infarction and were treated with primary angioplasty within 12 hours of symptom onset between August 1995 and December 1998. Patients were placed into 4 treatment groups depending on the adjunctive therapy they received: group 1, percutaneous transluminal coronary angioplasty (PTCA) ("balloon PTCA alone"; n = 220); group 2, PTCA plus intracoronary stent placement ("stent"; n = 128); group 3, PTCA plus abciximab therapy ("abciximab"; n = 104); and group 4, PTCA plus intracoronary stent placement plus abciximab therapy ("stent/abciximab"; n = 198). The patients' clinical characteristics, severity of disease, and total ischemia time on presentation were similar. At baseline, abciximab and stent/abciximab groups had a higher incidence of thrombus on coronary angiography. Postprocedural quantitative coronary analysis showed a significantly larger minimum luminal diameter in the stent and stent/abciximab groups than PTCA alone. Overall, stents were most efficacious in reducing target vessel revascularization rate, whereas abciximab was associated with a higher postprocedural Thrombolysis In Myocardial Infarction-3 trial flow and less "no reflow." The best angiographic result was achieved in the stent/abciximab group. Similarly, the primary combined end point of death, myocardial infarction, and target vessel revascularization at 30 days was the lowest (6.1%) in the stent/abciximab group. The combination of abciximab and stenting in primary angioplasty for acute myocardial infarction is thus synergistic and is associated with improved angiographic and clinical results at 30-day follow-up.

Short- and medium-term outcome differences in women and men after primary percutaneous transluminal mechanical revascularization for acute myocardial infarction.

Women presenting with acute myocardial infarction (AMI) have a higher mortality with conventional medical and thrombolytic therapy when compared with men. The outcome after primary percutaneous transluminal mechanical revascularization has not yet been fully investigated. This study was performed to compare the characteristics and the short- and medium-term outcomes of women and men with AMI treated with primary percutaneous revascularization. A total of 182 consecutive patients (62 women and 120 men) were included. Baseline clinical characteristics were similar except that women were older than men, presented more often in cardiogenic shock, and had smaller reference vessel diameters. Stents and abciximab were used equally, but abciximab was stopped more often in women before completion of the 12-hour infusion because of higher bleeding rates. Acute procedural success rates were similar (92% and 97%) but mortality was much higher in women, both at 30-day follow-up (100% vs 0.9%; p <0.05) and during a mean follow-up of 6.9 +/- 4.1 months (15% vs 4.4%; p <0.05). Women also experienced more unfavorable cardiovascular events (recurrent unstable angina or AMI, target vessel revascularization) than men. However, after control for baseline clinical differences in a multivariate analysis, gender was not an independent predictor of survival, whereas age, cardiogenic shock, and completion of a 12-hour abciximab infusion were.

Clinical and angiographic characteristics of exertion-related acute myocardial infarction.

CONTEXT: Vigorous physical exertion transiently increases the risk of acute myocardial infarction (MI), but little is known about the clinical characteristics of exertion-related MI. OBJECTIVE: To compare the clinical and angiographic characteristics of patients who had an exertion-related acute MI vs those who experienced an MI not related to exertion. DESIGN AND SETTING: Prospective observational cohort study of patients with an acute MI referred to a tertiary care hospital for primary angioplasty. PATIENTS: Of 1048 patients with acute MI, 640 (64 who experienced an exertion-related MI and 576 who did not) were selected for treatment with primary angioplasty and admitted between August 1995 and November 1998. MAIN OUTCOME MEASURES: Clinical characteristics of the patients, including their habitual physical activity (determined by the Framingham Physical Activity Index and the Lipid Research Clinic Physical Activity Questionnaire), angiographic findings during coronary angiography, and the relative risk (RR) of MI during exertion. RESULTS: Patients who experienced exertion-related MI were more frequently men (86% vs 68%), hyperlipidemic (62% vs 40%), and smokers (59% vs 37%), were more likely to present with ventricular fibrillation (20% vs 11%), Killip classification III or IV heart failure (44% vs 22%), single-vessel disease (50% vs 28%), and a large thrombus in the infarct artery (64% vs 35%) and were more likely to be classified as having very low or low activity (84% vs 66%). The RR of experiencing an MI during exertion was 10.1 times greater than the risk at other times (95% confidence interval [CI], 1.6-65.6), with the highest risk among patients classified as very low active (RR, 30.5; 95% CI, 4.4-209.9) and low active (RR, 20.9; 95% CI, 3.1-142.1). CONCLUSION: These results show that exertion-related MIs occur in habitually inactive people with multiple cardiac risk factors. These individuals may benefit from modest exercise training and aggressive risk-factor modification before they perform vigorous physical activity.

Enhanced local intracoronary delivery of heparin with the Infiltrator catheter: a comparative study.

The efficacy of local drug delivery in the treatment of coronary artery disease is limited by the relatively low delivery efficiency of the available devices. A unique local drug delivery device, the Infiltrator catheter (InterVentional Technologies, Inc.), has been designed specifically to enhance efficiency by injecting drugs directly into the arterial wall through microports mounted on the balloon surface. The purpose of this study was to assess the efficiency of delivery of this device in the porcine coronary model and to compare it to a previously validated device, the hydrogel balloon (Boston Scientific, Maple Grove, Minnesota). Studies were also performed to assess the pattern of intramural heparin deposition following delivery with the Infiltrator catheter and to assess the effect of the microports on vascular integrity. The efficiency of delivery was significantly greater with the Infiltrator catheter than with the hydrogel balloon (4.5% vs. 0.08%; p = 0.02). Similarly, the absolute amount of intramurally deposited heparin was greater with the Infiltrator (111.3 +/- 38.5 units vs. 2.4 +/- 0.85 units; p = 0.02) despite the fact that more heparin was delivered with the hydrogel catheter. Histologic studies revealed characteristic discrete puncture channels in the vessel wall due to penetration of the microports. Other than this histologic finding, there was no significant difference in the extent of architectural disruption between the Infiltrator and conventional balloon inflations. Fluorescein-labeled heparin studies revealed heparin to be diffusely distributed throughout the vessel wall immediately following delivery with the Infiltrator. We conclude that the Infiltrator catheterOs unique mechanism of delivery improves the efficiency of local drug delivery without excessive vessel wall trauma.

Abciximab in primary coronary angioplasty for acute myocardial infarction improves short- and medium-term outcomes.

OBJECTIVES: The purpose of this study was to compare the outcome of primary percutaneous transluminal coronary angioplasty for acute myocardial infarction (MI) when performed with or without the platelet glycoprotein IIb/IIIa antibody, abciximab. BACKGROUND: Abciximab improves the outcome of angioplasty but the effect of abciximab in primary angioplasty has not been investigated. METHODS: Data were collected from a computerized database. Follow-up was by telephone or review of outpatient or hospital readmission records. RESULTS: A total of 182 consecutive patients were included; 103 received abciximab and 79 did not. The procedural success rate was 95% in the two groups. At 30-day follow-up, the composite event rate of unstable angina, reinfarction, target vessel revascularization and death from all causes was 13.5% in the group of patients who did not receive abciximab, 4% (p < 0.05) in the abciximab group and 2.4% (p < 0.05) in the subgroup of patients (n = 87) who completed the 12-h abciximab infusion. At the end of follow-up (mean 7+/-4 months), the composite event rate was 32.4%, 17% (p < 0.05) and 13.1% (p < 0.01) in these three categories respectively. Abciximab bolus followed by a 12-h infusion was an independent predictor of event-free survival, in a Cox proportional hazards model (relative risk 0.49; 95% confidence interval 0.24 to 0.99; p < 0.05). CONCLUSIONS: Abciximab given at the time of primary angioplasty may improve the short- and medium-term outcome of patients with acute MI, especially when a 12-h infusion is completed.

Coronary angioplasty induces a systemic inflammatory response.

C-reactive protein (CRP) levels increased more than sixfold above baseline when measured 48 hours after elective percutaneous transluminal coronary angioplasty (PTCA) in patients without underlying inflammatory conditions and did not change significantly in controls undergoing coronary angiography. Only 3 of the 42 PTCA patients had clinical restenosis and underwent target vessel revascularization during the 6-month follow-up, but 2 of the 3 had very high CRP levels 48 hours after the procedure.

Site-specific intracoronary thrombolysis with urokinase-coated hydrogel balloons: acute and follow-up studies in 95 patients.

Conventional balloon angioplasty in the presence of intracoronary thrombus is associated with an elevated risk for acute myocardial infarction, emergency bypass surgery, and death. The purpose of this study was to assess the safety and efficacy of a new technique to treat thrombus-containing stenoses consisting of the local delivery of urokinase directly to the site of intraluminal clot with hydrogel-coated balloons. Ninety-five patients with angiographically apparent intracoronary thrombus were treated with urokinase-coated hydrogel balloons either prior to (n = 74) or following (n = 21) conventional balloon angioplasty. Clinical diagnoses for the study group included acute myocardial infarction in 50 patients, postinfarction angina in 23 patients, and unstable angina in 22 patients. All hydrogel balloons were initially coated with urokinase by immersing the inflated balloon in a concentrated Abbokinase solution (50,000 units/ml) for 60 s. All patients were subsequently treated with drug-coated balloons using a balloon:artery ratio of 1:1, a mean of 2.2 +/- 1.2 inflations, and a mean total inflation time of 7.5 +/- 4.9 min. Use of urokinase-coated balloons resulted in angiographic disappearance of intracoronary thrombus in 78 patients, improvement in 14, and no change in the remaining 3 patients. Following hydrogel balloon use for the entire 95 patients, TIMI flow increased from 1.4 +/- 1.2 to 2.9 +/- 0.4, minimal lumen diameter increased from 0.4 +/- 0.4 to 2.0 +/- 0.6 mm, and thrombus score decreased from 2.0 +/- 0.9 to 0.2 +/- 0.6 (all P < 0.01). Procedural and early in-hospital complications were noted in 7 of the 95 patients (7.4%) and included abrupt closure in 3 patients, distal embolization in 1 patient, no reflow in 1 patient, sidebranch occlusion in 1 patient, and late closure in 1 patient. Two of the 3 patients with abrupt closure and the single patient with late closure required intracoronary stenting to maintain vessel patency. Two of these 7 patients sustained small myocardial infarctions, although no patient required emergency bypass surgery or experienced a procedural death. Late clinical follow-up (mean = 8.3 +/- 6.6 months; range = 2 wk to 29 mo) demonstrated adverse recurrent events in 29 of the 95 patients (30.5%), including death (n = 5), myocardial infarction (n = 2), and recurrence of angina (n = 22). The results of this study suggest that intracoronary thrombolysis can be safely and rapidly achieved by using limited quantities of urokinase delivered directly to the site of intraluminal clot with hydrogel balloons. Use of this technique may result in improved acute outcomes in comparison with conventional techniques currently being used to treat thrombus-containing stenoses.

Treatment of thrombotic saphenous vein bypass grafts using local urokinase infusion therapy with the Dispatch catheter.

Percutaneous treatment of thrombotic stenoses or total occlusions in aged saphenous vein bypass grafts is associated with a significant incidence of complications primarily related to distal embolization. The purpose of this study was to assess the efficacy of local urokinase delivery with the Dispatch catheter prior to balloon angioplasty and/or intragraft stent placement as a new technique of vein graft revascularization. Local urokinase delivery with the Dispatch catheter was performed in 15 saphenous vein grafts (mean age = 11.7 +/- 2.5 yr) in 13 patients with unstable or postinfarction angina. The target lesion was a total occlusion in 5 of the procedures and a severe vein graft stenosis in the remaining 10. In all cases, urokinase was administered directly to the site of the stenosis/occlusion via the Dispatch catheter at 0.5 cc/min and at a concentration of 30,000 units/cc. The mean urokinase infusion time for the 15 procedures was 33 +/- 10 min (range = 10-60 min) and the mean urokinase dose was 495,000 +/- 158,000 units (range = 150,000-900,000 units). Following Dispatch therapy, mean minimal lumen diameter increased from 0.34 +/- 0.32 to 1.81 +/- 0.78 mm (P < 0.01), mean TIMI flow increased from 1.9 +/- 1.4 to 2.8 +/- 0.8 (P < 0.06), and mean thrombus score was reduced from 2.3 +/- 0.6 to 0.3 +/- 0.8 (P < 0.01). Mild no reflow was noted in two cases, although no patient demonstrated angiographic evidence of gross distal embolization. One of the patients with no reflow also demonstrated a small increase in cardiac enzymes. Subsequent balloon angioplasty/stent placement was successful in 14 of the 15 procedures (93% success rate). This preliminary report suggests that pretreatment of thrombotic saphenous vein graft stenoses with local urokinase delivery via the Dispatch catheter may decrease intragraft thrombus and possibly decrease the incidence of vascular complications associated with percutaneous intervention. This technique may allow for recanalization of totally occluded vein grafts with large clot burdens by using significantly less urokinase and shorter drug administration times than conventional infusion protocols.

Recanalization of totally occluded saphenous vein grafts using local urokinase delivery with the Dispatch catheter.

Current techniques for the percutaneous revascularization of totally occluded vein grafts are limited by a low initial success rate, a significant incidence of distal embolization, and a high rate of early graft reclosure. This case report describes two patients in whom graft recanalization was attempted with the combined use of balloon angioplasty/intra-graft stent placement and local urokinase delivery using a new angiotherapy catheter. Successful recanalization was achieved in both patients without major complications, in spite of a large thrombus burden as demonstrated by angiography.

Treatment of intracoronary thrombus with local urokinase infusion using a new, site-specific drug delivery system: the Dispatch catheter.

BACKGROUND: The presence of intracoronary thrombus significantly increases the risk of conventional balloon angioplasty because of a high incidence of abrupt closure, distal embolization, and no-reflow phenomenon. The purpose of this study was to assess a new technique for treating intracoronary thrombus consisting of the local delivery of urokinase directly to the angioplasty site with a novel, catheter-based, drug delivery system. METHODS: The Dispatch catheter is a new local, drug-delivery device that allows for the prolonged infusion of therapeutic agents at an angioplasty site while still maintaining distal coronary perfusion. Six patients with angiographic or clinical evidence of intracoronary thrombus were treated with 150,000 units of urokinase over a 30-min period using this device prior to or following conventional balloon angioplasty and/or directional atherectomy. RESULTS: Successful delivery of urokinase directly to the angioplasty site was achieved in all 6 patients without hemodynamic or electrocardiographic compromise. In all six cases, local urokinase therapy resulted in complete dissolution of angiographic intracoronary thrombus and/or reduction of the coronary stenosis. Limited ischemia due to side-branch occlusion by the catheter's coils was noted in one patient. Distal embolization or no-reflow phenomenon were not observed in any case. CONCLUSION: The local drug-delivery catheter used in this study was able to successfully and rapidly achieve intracoronary thrombolysis by delivering limited quantities of urokinase directly to the angioplasty site, while still maintaining distal coronary perfusion. This technique of local, thrombolytic drug delivery may be useful in the percutaneous treatment of intracoronary thrombus and thrombus-containing stenoses.

Inhibition of platelet deposition and lysis of intracoronary thrombus during balloon angioplasty using urokinase-coated hydrogel balloons.

BACKGROUND: Conventional balloon angioplasty of intracoronary thrombus is associated with a high incidence of abrupt closure, distal embolization, and no-reflow phenomenon. The purpose of this study was to assess a new technique for treating intracoronary thrombus consisting of the local delivery of urokinase directly to the angioplasty site with urokinase-coated hydrogel balloons. METHODS AND RESULTS: We assessed local urokinase delivery using hydrogel balloons in four protocols. First, we evaluated the pharmacokinetics of urokinase delivery in vitro using 125I-labeled urokinase to measure drug loading onto hydrogel balloons, drug retention by the hydrogel polymer during blood exposure, and drug transfer from the balloon surface to the arterial wall during balloon dilatation. Second, we measured 125I-urokinase washoff from the hydrogel balloon in the intact circulation and intramural drug delivery during in vivo balloon angioplasty in 10 anesthetized New Zealand rabbits. Third, we assessed the effect of local urokinase delivery on 111In-labeled platelet deposition after balloon angioplasty in vivo in 13 porcine carotid or iliac arteries dilated with urokinase-coated balloons and compared them with contralateral control arteries dilated with saline-coated balloons. Finally, we determined the clinical efficacy of urokinase-coated balloons in 15 patients with intracoronary thrombus, including 7 who demonstrated abrupt thrombotic closure after conventional angioplasty. Between 241 and 1509 U urokinase could be loaded onto hydrogel balloons ranging in size from 2 to 8 mm. In vitro and in vivo studies demonstrated that hydrogel balloons absorbed significantly more urokinase and demonstrated less drug wash-off than nonhydrogel balloons (P < .01). Similarly, both in vitro and in vivo studies demonstrated urokinase transfer from the hydrogel to the arterial wall during balloon angioplasty, with greater intramural drug deposition with larger balloons (P < .01). Local urokinase delivery after in vivo porcine angioplasty decreased 111In-labeled platelet deposition by 47% compared with contralateral control vessels (P = .03). Use of urokinase-coated balloons in patients with intracoronary thrombus resulted in thrombus dissolution and reversal of abrupt closure in all cases, without evidence of distal embolization. CONCLUSIONS: With the use of hydrogel-coated balloons, urokinase can be delivered locally to an angioplasty site. This technique decreases platelet deposition after in vivo balloon angioplasty and is efficacious in treating intracoronary thrombus in patients, including those with abrupt thrombotic closure.

Intracardiac ultrasound determination of left ventricular volumes: in vitro and in vivo validation.

OBJECTIVES: This study was designed to assess the feasibility of calculating left ventricular volumes using intracardiac ultrasound. BACKGROUND: Previous studies have validated transthoracic echocardiographic determinations of left ventricular volumes and have indicated the superiority of Simpson rule reconstruction algorithms. The feasibility of imaging the left ventricle with intracardiac ultrasound has also been demonstrated. METHODS: The determination of left ventricular volumes with Simpson rule reconstruction of intracardiac ultrasound images was evaluated in two phases. In vitro validation was performed in 29 animal hearts preserved in either a nondistended or distended state. Latex cast volumes were the reference standard. In vivo studies used 14 pigs, and compared intracardiac ultrasound volumes and ejection fraction with single-plane contrast angiographic values. A 12.5-MHz device was used to record short-axis images at 0.5-cm intervals. These were used to reconstruct the ventricle as a stack of cylindric elements using all imaged levels as well as sections recorded every 1 and 2 cm and at a single midventricular level. RESULTS: In the in vitro hearts, when all recorded sections were used, there was excellent agreement between intracardiac ultrasound and latex cast volumes (intracardiac ultrasound volume = 0.89 latex cast volume + 2.22, r = 0.95; intracardiac ultrasound volume = 0.97 latex cast volume + 0.91, r = 0.99) for nondistended and distended hearts, respectively. In vivo, there was again close correspondence between ultrasound and angiographic volumes (intracardiac ultrasound volume = 1.04 angiographic volume - 3.6, r = 0.91). The relation between intracardiac ultrasound and angiographic ejection fraction was fair (intracardiac ultrasound ejection fraction = 1.00 angiographic ejection fraction + 6.85, r = 0.69). Excellent correlations for the volumes were maintained as the number of cross sections was reduced to those recorded every 1 and 2 cm (r = 0.87 to 0.99). With a single midventricular site more variable but generally good correlations were obtained (r = 0.77 to 0.99). CONCLUSIONS: The application of Simpson rule reconstruction to short-axis images of the left ventricle obtained with intracardiac ultrasound provides accurate determination of left ventricular volumes in animal hearts. This technique may prove useful in the analysis of left ventricular structure and function.

Low pressure radiofrequency balloon angioplasty: evaluation in porcine peripheral arteries.

OBJECTIVES: The purpose of this study was to evaluate the efficacy of radiofrequency-powered thermal balloon angioplasty in an in vivo porcine model. BACKGROUND: Various modes of thermal energy used adjunctively during balloon angioplasty have demonstrated the potential to enhance the results of acute lumen dilation. METHODS: In normal pigs, 75 peripheral arteries were dilated with a newly designed, radiofrequency-powered, thermal angioplasty balloon. All inflations were performed at 2-atm pressure for 85 s. Dilations were performed either with (hot) or without (cold) the application of heat. Lumen dimensions and vessel morphology were assessed with intravascular ultrasonography. At the end of each study, dilated arterial segments were harvested for histologic examination. RESULTS: Single cold balloon inflations resulted in a 12.7% increase in arterial cross-sectional area whereas single hot inflations resulted in a 22.9% increase (p < 0.03). Similarly, when multiple cold inflations were compared with multiple hot inflations, two, three and four sequential hot inflations resulted in a significantly greater increase in cross-sectional area than an equivalent number of cold inflations (p < 0.03). Histologic examination demonstrated a temperature-dependent effect on the depth of medial necrosis and extent of arterial wall thinning (p < 0.001) as well as evidence for uniform alteration of elastic tissue fibers at temperatures of > or = 60 degrees C (p < 0.03). CONCLUSIONS: Low pressure radiofrequency thermal balloon angioplasty results in a greater increase in cross-sectional area in porcine peripheral arteries than does nonheated conventional balloon angioplasty. The pathologic basis for this enhanced dilation may be a temperature-dependent effect on medial necrosis, thinning of the arterial wall or alteration of vascular elastic fibers, alone or in combination.

Epoprostenol sodium (prostacyclin) infusion in acute myocardial infarction.

Epoprostenol (prostacyclin) is a potent inhibitor of platelet aggregation and causes relaxation of vascular smooth muscle. These effects may be beneficial in patients with acute myocardial infarction. The effect of epoprostenol infusion in patients with acute myocardial infarction was evaluated in a randomised double blind study of 45 patients with evidence of myocardial infarction of less than 16 hours' duration. The patients were given a 72 hour infusion of epoprostenol (23) or placebo (22). The maximum dose was 5 ng/kg/min. The mean time to treatment was 8.3 hours (range 3.8-15.9 hours). The mean dose was 4.9 ng/kg/min. The patients were followed until day 30. No significant differences were found between the groups in mortality, development of congestive heart failure, cardiogenic shock, arrhythmias, recurrent chest pain, reinfarction, peak creatine kinase concentration, or the time taken to attain peak creatine kinase concentration. No significant difference in baseline ejection fraction was noted between groups, and no significant change in ejection fraction occurred within each group or between groups. The only significant side effect was the development of facial flushing in the epoprostenol group. In this pilot study epoprostenol was well tolerated by patients with acute myocardial infarction. No benefit from epoprostenol could be demonstrated at the dose range used when the drug was administered within 16 hours of the onset of symptoms.

Effect of aging on the clinical significance of fever in ambulatory adult patients.

To study the effect of age on ultimate outcome of febrile illness, the authors prospectively studied 1,202 adult patients who came to an emergency room/walk-in clinic setting with temperatures of 101.0 degrees F (38.3 degrees C) or more. The patients were divided into four age categories: 17 to 40 years, 40 to 59 years, 60 to 79 years, and 80 years old or older. Advancing age was significantly (P less than 0.0005) associated with more serious disease, a higher rate of bacterial pathogen isolation, and a higher rate of life-threatening or deadly consequences. Of patients 17-39 years old, 58.2 per cent had viral syndromes, otitis media, or pharyngitis as the causes of fever. Of patients aged 40-59 years, only 20.7 per cent had one of these diseases. However, of patients 60 years old or older, only 4.1 per cent (15 of 370) had viral syndromes, otitis media, or pharyngitis, and the overall rate of hospitalization for this group was 92.5 per cent. The authors conclude that febrile patients 60 years old or older seen in emergency room/ambulatory care settings are extremely likely to have serious diseases. Caution should be exercised before concluding that their fevers are of benign origin.