Intracoronary beta-radiation to reduce restenosis after balloon angioplasty and stenting; the Beta Radiation In Europe (BRIE) study.

AIMS: The BRIE trial is a registry evaluating the safety and performance of (90)Sr delivered locally (Beta-Cath TM system of Novoste) to de-novo and restenotic lesions in patients with up to two discrete lesions in different vessels. METHODS AND RESULTS: In total, 149 patients (175 lesions) were enrolled; 62 treated with balloons and 113 with stents. The restenosis rate, the minimal luminal diameter and the late loss were determined in three regions of interest: (a) in a subsegment of 5mm containing the original minimal luminal diameter pre-intervention termed target segment; (b) the irradiated segment, 28 mm in length, and (c) the entire analysed segment, 42 mm in length, termed the vessel segment. Binary restenosis was 9.9% for the target segment, 28.9% for the irradiated segment, and 33.6% for the vessel segment. These angiographic results include 5.3% total occlusions. Excluding total occlusions binary restenosis was 4.9%, 25% and 29.9%, respectively. At 1 year the incidence of major adverse cardiac events placed in a hierarchical ranking were: death 2%, myocardial infarction 10.1%, CABG 2%, and target vessel revascularization 20.1%. The event-free survival rate was 65.8%. Non-appropriate coverage of the injured segment by the radioactive source termed geographical miss affected 67.9% of the vessels, and increased edge restenosis significantly (16.3% vs 4.3%, P=0.004). It accounted for 40% of the treatment failures. CONCLUSION: The results of this registry reflect the learning process of the practitioner. The full therapeutic potential of this new technology is reflected by the restenosis rate at the site of the target segment. It can only be unravelled once the incidence of late vessel occlusion and geographical miss has been eliminated by the prolonged use of thienopyridine, the appropriate training of the operator applying this new treatment for restenosis prevention, and the use of longer sources.

The ARTS study (Arterial Revascularization Therapies Study).

The rising costs of health care have forced policy makers to make choices, and new treatments are increasingly assessed in terms of the balance between additional costs and additional effects. The recent recognition that stenting has a major and long-lasting effect enhancing balloon PTCA procedure has made it imperative to compare in patients with multivessel disease the standard surgical procedure with multiple stenting in a large scale multinational and multicentre approach (19 countries, 68 sites). Selection and inclusion of patients is based on a consensus of the cardiac surgeon and interventional cardiologist on equal 'treatability' of patients by both techniques with analysis of clinical follow-up (event-free survival) on the short (30 day), medium (1 year), and long-term (3 and 5 year) with analysis of cost-effectiveness and quality of life (EuroQol and SF-36). Of the entire trial, the primary null hypothesis which needs to be rejected is that there will be no difference in event-free survival or effectiveness (E), at 1 year and also that the direct and indirect costs (C) per event-free year are not different between surgery or stenting. For this to become significant with a power of 90% one needs 1200 patients. Between April 97 and June 98, 1205 patients have been randomized with a monthly recruitment of 83 patients. Expected costs, effects and cost-effectiveness ratio (CE ratio) are: Stent high costs 2 VDStent high costs 3 VDStent low costs 2 VDStent low costs 3 VDCABG costs (C)$19.297$24.566$16.638$20.456$21.350 effects (E)81%81%81%81%88% CE ratio$23.876$30.397$20.586$25.322$24.348 Clinically, stenting is not expected to be more effective than CABG, but should be cost effective in both the 2- and 3-VD group when using the lower cost estimate and in the 2 VD group when using the higher cost assumptions.

Stent implantation in acute myocardial infarction using a heparin-coated stent: a pilot study as a preamble to a randomized trial comparing balloon angioplasty and stenting.

Preliminary experience with primary stenting in myocardial infarction has suggested a greater benefit in clinical outcome than has been obtained with direct balloon angioplasty. However, subacute thrombosis (SAT) remains a limitation for this new mode of therapy. In the BENESTENT II Pilot and main trials, the incidence of SAT with the heparin-coated Palmaz-Schatz stent was only 0.15%. Therefore, as a preamble to a large randomized trial, the feasibility and safety of the use of the Heparin-Coated Palmaz-Schatz trade mark Stent in Acute Myocardial Infarction (AMI) was tested in 101 patients enrolled between April and September 1996 in 18 clinical centres. In 101 stent-eligible AMI patients, as dictated by protocol, a heparin-coated stent was implanted. The primary objectives were to determine the in-hospital incidence of major adverse cardiac events (MACE: death, MI, target lesion revascularization) and bleeding complications, while the secondary objectives were the procedural success rate and the MACE, the restenosis and reocclusion rates at 6.5 months. Stent implantation (n 3 129 stents) was successful in 97 patients of the 101 who were included in this trial. During their hospital stay, two patients died and no patient experienced re-infarction, ischaemia prompting re-PTCA or CABG. Four patients suffered a bleeding complication, three major and one minor, of whom three required surgical repair. At 210 days follow-up, 81% of the patients were event free. At 6.5 months restenosis was documented in 18% of the 88 patients who underwent follow-up angiography, including three total occlusions. The results, both with respect to QCA and the occurrence of MACE, compare favourably with studies using elective stenting in both stable and unstable angina patients. As a result of this pilot study, a large randomized trial comparing direct balloon angioplasty with direct stenting in 900 patients with AMI was initiated in December 1996.

Randomized comparison of angioplasty of complex coronary lesions at a single center. Excimer Laser, Rotational Atherectomy, and Balloon Angioplasty Comparison (ERBAC) Study.

BACKGROUND: The purpose of this study was to test whether coronary revascularization with ablation of either excimer laser or rotational atherectomy can improve the initial angiographic and clinical outcomes compared with dilatation (balloon angioplasty) alone. METHODS AND RESULTS: At a single center, a total of 685 patients with symptomatic coronary disease warranting elective percutaneous revascularization for a complex lesion were randomly assigned to balloon angioplasty (n = 222), excimer laser angioplasty (n = 232), or rotational atherectomy (n = 231). The primary end point was procedural success (diameter stenosis < 50%, absence of death, Q-wave myocardial infarction, or coronary artery bypass surgery). The patients who underwent rotational atherectomy had a higher rate of procedural success than those who underwent excimer laser angioplasty or conventional balloon angioplasty (89% versus 77% and 80%, P = .0019), but no difference was observed in major in-hospital complications (3.2% versus 4.3% versus 3.1%, P = .71). At the 6-month follow-up, revascularization of the original target lesion was performed more frequently in the rotational atherectomy group (42.4%) and the excimer laser group (46.0%) than in the angioplasty group (31.9%, P = .013). CONCLUSIONS: Procedural success of rotational atherectomy is superior to laser angioplasty and balloon angioplasty; however, it does not result in better late outcomes. The role of plaque debulking before balloon dilatation in percutaneous coronary revascularization remains to be fully defined.

Prospective case-control comparison of percutaneous transluminal coronary revascularization in patients with multivessel disease treated in 1986-1987 versus 1991: improved in-hospital and 12-month results. Multivessel Angioplasty Prognosis Study (MAPS) Group.

OBJECTIVES: This study sought to ascertain whether early and 12-month clinical outcomes after percutaneous coronary revascularization have improved between 1986-1987 and 1991. BACKGROUND: Since the mid-1980s, when the results of percutaneous revascularization were considered to be somewhat static, justifying large-scale clinical trials of percutaneous transluminal coronary angioplasty versus other modes of therapy, balloon technology has improved, and several new percutaneous revascularization techniques have become available. The clinical results of the current integrated approach to revascularization compared with those for coronary angioplasty alone in the late 1980s are not known. METHODS: In this prospective case-control study, 200 consecutively treated patients with multivessel disease in 1991 were studied prospectively and compared with 400 consecutive patients from the same centers during 1986-1987. Patients from 1991 were matched with earlier patients on the basis of four previously described prognostic determinants (left ventricular ejection fraction, presence of unstable angina, diabetes and target lesion morphology score) and the treating institution and were assessed for treatment outcome (completeness of revascularization, procedural success and event-free survival [freedom from death, myocardial infarction and further revascularization]). RESULTS: The 1991 cohort of patients was older (mean [+/- SD] age 62 +/- 11 vs. 58 +/- 11 years, p < 0.001) and tended to have slightly worse left ventricular function (ejection fraction 56 +/- 10% vs. 58 +/- 11%, p = 0.009) than the 1986-1987 cohort. Overall lesion morphology risk scores were similar. New devices (other than coronary angioplasty) were used in 26% of patients. The 1991 patient cohort had more frequent total revascularization (35% vs. 21%, p = 0.003), fewer emergency bypass operations (1.0% vs. 5.5%, p = 0.006) and an improved overall procedural success rate (90% vs. 84%, p = 0.04). In addition, at 12 months the event-free survival rate was superior in the 1991 cohort (73.3% vs. 63.6%, p = 0.02), although there was no difference in infarct-free survival rate (94.6% vs. 93.2%, p = NS). CONCLUSIONS: Improved results with percutaneous revascularization in 1991 have important implications for patient care and interpretation of ongoing randomized trials enrolling patients in the late 1980s and intending to compare standard coronary angioplasty with other forms of therapy.

Randomized trial comparing two devices: the Palmaz-Schatz stent and the Strecker stent in bail-out situations.

UNLABELLED: To assess whether differences in design (geometry, flexibility) and material (electrostatic behavior) may influence the acute and late outcome following intracoronary stent implantation in the treatment of acute or threatened closure after prolonged balloon inflations, 50 patients were randomized to receive either a Palmaz-Schatz stent (n = 25) or a Strecker stent (n = 25). RESULTS: [table: see text] CONCLUSION: Both Palmaz-Schatz and Strecker stents are equally effective in restoring vessel patency in bail-out situations. The incidence of complications is high and similar for both stents if they were used after failed prolonged balloon inflations. Differences in design and material do not seem to influence the results.

Prophylactic versus standby cardiopulmonary support for high risk percutaneous transluminal coronary angioplasty.

OBJECTIVES: Data from a national registry of 23 centers using cardiopulmonary support (CPS) were analyzed to compare the risks and benefits of prophylactic CPS versus standby CPS for patients undergoing high risk coronary angioplasty. BACKGROUND: Early data from the CPS registry documented a high angioplasty success rate as well as a high procedural morbidity rate. Because of this increased morbidity some high risk patients were placed on standby CPS instead of prophylactic CPS. METHODS: Patients in the prophylactic CPS group had 18F or 20F venous and arterial cannulas inserted and cardiopulmonary bypass initiated. Patients in the standby CPS group were prepared for institution of cardiopulmonary bypass, but bypass was not actually initiated unless the patient sustained irreversible hemodynamic compromise. RESULTS: There were 389 patients in the prophylactic CPS group and 180 in the standby CPS group. The groups were comparable with respect to most baseline characteristics, except that left ventricular ejection fraction was lower in the prophylactic CPS group. Thirteen of the 180 patients in the standby CPS group sustained irreversible hemodynamic compromise during the angioplasty procedure. Emergency institution of CPS was successfully initiated in 12 of these 13 patients in < 5 min. Procedural success was 88.7% for the prophylactic and 84.4% for the standby CPS group (p = NS). Major complications did not differ between groups. However, 42% of patients in the prophylactic CPS group sustained femoral access site complications or required blood transfusions, compared with only 11.7% of patients in the standby CPS group (p < 0.01). Among patients with an ejection fraction < or = 20%, procedural morbidity remained significantly higher in the prophylactic CPS group (41% vs. 9.4%, p < 0.01), but procedural mortality was higher in the standby group (4.8% vs. 18.8%, p < 0.05). CONCLUSIONS: Patients in the standby and prophylactic CPS groups had comparable success and major complication rates, but procedural morbidity was higher in the prophylactic group. When required, standby CPS established immediate hemodynamic support during most angioplasty complications. For most patients, standby CPS was preferable to prophylactic CPS during high risk coronary angioplasty. However, patients with extremely depressed left ventricular function (ejection fraction < 20%) may benefit from institution of prophylactic CPS.

A randomized trial of late reperfusion therapy for acute myocardial infarction. Thrombolysis and Angioplasty in Myocardial Infarction-6 Study Group.

BACKGROUND: Experimental and observational clinical studies of acute coronary occlusion have suggested that late reperfusion prevents infarct expansion and facilitates myocardial healing. The purpose of this trial was to assess whether infarct vessel patency could be achieved in late-entry patients and what benefit, if any, can be demonstrated. METHODS AND RESULTS: In a double-blind fashion, 197 patients with 6 to 24 hours of symptoms and ECG ST elevation were randomly assigned to tissue-type plasminogen activator (100 mg over 2 hours) or placebo. Coronary angiography within 24 hours was used to determine infarct vessel patency status. Patients with infarct-related occluded arteries were then eligible for a second randomization to either angioplasty (34 patients) or no angioplasty (37 patients). Ventricular function and cavity size were reassessed at 1 month by gated blood pool scintigraphy and at 6 months by repeat cardiac catheterization. The primary end point, infarct vessel patency, was 65% for plasminogen activator patients compared with 27% in the placebo group (p less than 0.0001). There were no differences between these groups in ejection fraction or infarct zone regional wall motion at 1 or 6 months. At 6 months, infarct vessel patency was 59% in both groups. In the placebo group, there was a significant increase in end-diastolic volume from acute phase of 127 ml to 159 ml at 6-month follow-up (p = 0.006) but no increase in cavity size for the plasminogen activator group patients. Coronary angioplasty was associated with an initial 81% recanalization success and improved ventricular function at 1 month, but by late follow-up no advantage could be demonstrated for this procedure, and there was a 38% spontaneous recanalization rate in the patients assigned to no angioplasty. CONCLUSIONS: The study demonstrates that it is possible to achieve infarct vessel recanalization in the majority of late-entry patients with either thrombolytic therapy or angioplasty. Thrombolytic intervention had a favorable effect on prevention of cavity dilatation and left ventricular remodeling, but there are no late benefits on systolic function after thrombolysis or coronary angioplasty. The conclusions concerning overall potential benefit of applying late reperfusion therapy will require data from large-scale trials designed to assess mortality reduction.

Reduction of ischemia with a new flow-adjustable hemoperfusion pump during coronary angioplasty. The Coronary Hemoperfusion Ischemia Prevention Study (CHIPS) Investigators.

A new flow-adjustable pump for coronary hemoperfusion to prevent ischemia during routine coronary angioplasty was evaluated in a multicenter prospective study of 110 patients. The protocol included patients who had angina or ST segment elevation during a control balloon inflation of less than or equal to 3 min. Hemoperfusion was performed by means of a new large lumen angioplasty catheter utilizing the patient's renal vein or femoral artery blood. Vessels perfused were the left anterior descending coronary artery (n = 74), right coronary artery (n = 39), left circumflex artery (n = 9) and coronary vein grafts (n = 15). Mean (+/- SD) perfusion flow was 41 +/- 9 ml/min (range 17 to 70); mean perfusion time was 9.3 +/- 4 min (median 8.5, range 2 to 30). Chest pain score (0 to 4) decreased from 2.9 +/- 1 to 1.4 +/- 1 during hemoperfusion (p less than 0.001); ST segment elevation score (0 to 4) decreased from 2.6 +/- 1 to 0.7 +/- 1 (p less than 0.005) and inflation time increased from 1.3 +/- 0.9 to 7 +/- 4 min, (p less than 0.001). At least a 50% increase in tolerated inflation time was obtained in 104 patients (95%). Free plasma hemoglobin and creatine kinase levels did not increase significantly over baseline values. Angioplasty was successful in 107 patients (97%), with mean stenosis reduced from 87 +/- 11% to 20 +/- 17%; 3 patients had urgent bypass surgery, 2 (1.8%) had a myocardial infarction (1 Q wave, 1 non-Q wave) and 2 (1.8%) died later in the hospital of probable noncoronary causes.(ABSTRACT TRUNCATED AT 250 WORDS)

Determinants of 2-year outcome after coronary angioplasty in patients with multivessel disease on the basis of comprehensive preprocedural evaluation. Implications for patient selection. The Multivessel Angioplasty Prognosis Study Group.

BACKGROUND: To assess the likelihood of intermediate-term event-free survival (freedom from death, coronary artery bypass surgery, and myocardial infarction) in patients with multivessel coronary disease undergoing coronary angioplasty, 350 consecutive patients from four clinical sites were carefully evaluated and followed for 22 +/- 10 months. METHODS AND RESULTS: Eight clinical variables were evaluated at the clinical sites, and 23 angiographic variables describing the number, morphology, and topography of coronary stenoses were evaluated at a core angiographic laboratory. Most patients had Canadian Cardiovascular Society class III or IV angina (72%), two-vessel coronary disease (68%), and well-preserved left ventricular function (mean ejection fraction, 58 +/- 12%; range, 18-85%). Follow-up was complete in 99% of patients. At 2 years, event-free survival was 72%, overall survival was 96%, freedom from bypass surgery was 82%, and freedom from nonfatal myocardial infarction without surgery was 96%. Sequential Cox proportional hazards regression analyses allowing stepwise entry of variables prospectively coded as simple, as of intermediate complexity, or as complex found event-free survival to be independently predicted by low Canadian Cardiovascular Society angina class, no diabetes, no proximal left anterior descending stenoses, and the sum of stenosis simplified risk-territory scores of 15 or less. In the absence of class IV angina and these risk factors, 2-year event-free survival was 87% and overall survival was 100%. In the presence of two or more of these risk factors, event-free survival was less than 50%. CONCLUSIONS: Recognition of risk factors for poor long-term outcome in this setting may improve clinical decision making and provide a framework on which to base meaningful subgroup analyses in randomized trials assessing the efficacy of coronary angioplasty.

Predictors of cardiac survival after percutaneous transluminal coronary angioplasty in patients with severe left ventricular dysfunction.

To assess the outcome of percutaneous transluminal coronary angioplasty (PTCA) in patients with severe left ventricular (LV) dysfunction and to determine the predictors of mortality, 73 patients with LV ejection fraction less than or equal to 40% who underwent initial PTCA were analyzed. The majority of patients had prior (greater than 1 week) myocardial infarction (62 patients, 85%). Congestive heart failure and unstable angina were present in 24 (45%) and 49 (67%) patients, respectively. Multivessel coronary artery disease was present in 60 (83%). The LV ejection fraction ranged from 14 to 40% (mean 34%). Intraaortic balloon pump (15%) and percutaneous cardiopulmonary bypass support (4%) was used infrequently. Angiographic success was obtained in 109 of 128 lesions (85%) attempted. Complete revascularization was obtained in 16 of 60 patients with clinical success. Procedure-related mortality was 5% (4 patients). All patients were followed from greater than or equal to 6 to less than or equal to 71 months (average 26). The estimated survival was 79 +/- 5%, 74 +/- 6%, 66 +/- 7% and 57 +/- 8% at 1, 2, 3 and 4 years, respectively. A Cox regression analysis revealed that the presence of congestive heart failure, a lower LV ejection fraction and a higher myocardial jeopardy score for contractile myocardium were independent predictors of survival after PTCA in patients with LV dysfunction. In conclusion, a high-risk subset can be identified among patients with severe LV dysfunction who undergo PTCA.

Predictors of long-term cardiac survival in patients with multivessel coronary artery disease undergoing percutaneous transluminal coronary angioplasty.

The predictors of 5-year cardiac survival in patients with multivessel coronary artery disease (CAD) undergoing percutaneous transluminal coronary angioplasty (PTCA) were analyzed in a series of 637 consecutive patients. The average age was 59 +/- 11 years in 472 men and 165 women. Diabetes mellitus, previous myocardial infarction and unstable angina were present in 119 (19%), 261 (41%) and 305 (47%) patients, respectively. Angiographically, 460 patients had 2-vessel and 177 patients had 3-vessel CAD. The left ventricular contraction score was greater than or equal to 12 in 55 patients. Angiographic success (less than 50% residual stenosis) was achieved in 85% of the 1,343 narrowings and clinical success was obtained in 526 (83%) of the 637 patients. Complete revascularization was obtained in 177 (34%) of 526 successful patients. Procedure-related complications resulted in death in 9 patients (1.4%), in Q-wave myocardial infarction only in 6 patients (0.9%) and in emergency bypass surgery in 44 patients (6.9%) (of whom 10 had Q-wave myocardial infarction). Follow-up for greater than or equal to 1 year and up to 6 years after PTCA was obtained in 608 (95%) of the 637 patients. To determine the predictors of 5-year cardiac survival, 28 clinical, angiographic and procedural variables were analyzed by Cox proportional-hazards regression. The estimated 5-year survival after PTCA was 88 +/- 2% in successful patients and 77 +/- 5% in patients in whom PTCA was unsuccessful (p less than 0.001). When clinical success was forced into the Cox regression, the left ventricular contraction score of greater than or equal to 12, diabetes mellitus and age greater than or equal to 65 years showed additional adverse effects on survival.(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary morphologic and clinical determinants of procedural outcome with angioplasty for multivessel coronary disease. Implications for patient selection. Multivessel Angioplasty Prognosis Study Group.

To assess the likelihood of procedural success in patients with multivessel coronary disease undergoing percutaneous coronary angioplasty, 350 consecutive patients (1,100 stenoses) from four clinical sites were evaluated. Eighteen variables characterizing the severity and morphology of each stenosis and 18 patient-related variables were assessed at a core angiographic laboratory and at the clinical sites. Most patients had Canadian Cardiovascular Society class III or IV angina (72%) and two-vessel coronary disease (78%). Left ventricular function was generally well preserved (mean ejection fraction, 58 +/- 12%; range, 18-85%) and 1.9 +/- 1.0 stenoses per patient had attempted percutaneous coronary angioplasty. Procedural success (less than or equal to 50% final diameter stenosis in one or more stenoses and no major ischemic complications) was achieved in 290 patients (82.8%), and an additional nine patients (2.6%) had a reduction in diameter stenosis by 20% or more with a final diameter stenosis 51-60% and were without major complications. Major ischemic complications (death, myocardial infarction, or emergency bypass surgery) occurred in 30 patients (8.6%). In-hospital mortality was 1.1%. Stepwise regression analysis determined that a modified American College of Cardiology/American Heart Association Task Force (ACC/AHA) classification of the primary target stenosis (with type B prospectively divided into type B1 [one type B characteristic] and type B2 [greater than or equal to two type B characteristics]) and the presence of diabetes mellitus were the only variables independently predictive of procedural outcome (target stenosis modified ACC/AHA score; p less than 0.001 for both success and complications; diabetes mellitus: p = 0.003 for success and p = 0.016 for complications). Analysis of success and complications on a per stenosis dilated basis showed, for type A stenoses, a 92% success and a 2% complication rate; for type B1 stenoses, an 84% success and a 4% complication rate; for type B2 stenoses, a 76% success and a 10% complication rate; and for type C stenoses, a 61% success and a 21% complication rate. The subdivision into types B1 and B2 provided significantly more information in this clinically important intermediate risk group than did the standard ACC/AHA scheme. The stenosis characteristics of chronic total occlusion, high grade (80-99% diameter) stenosis, stenosis bend of more than 60 degrees, and excessive tortuosity were particularly predictive of adverse procedural outcome. This improved scheme may improve clinical decision making and provide a framework on which to base meaningful subgroup analysis in randomized trials assessing the efficacy of percutaneous coronary angioplasty.

Attenuation of pulsus alternans during coronary angiography.

Following coronary angiography in a patient with cardiomyopathy and pulsus alternans, we observed a transient but marked attenuation of the alternation in pulse pressure associated with an elevation in pulmonary artery pressure. Attenuation of pulsus alternans has been rarely reported and may represent further deterioration of ventricular function.

Rapid identification of the course of anomalous coronary arteries in adults: the "dot and eye" method.

It is often difficult to delineate the true course of anomalous coronary arteries by angiography because it only provides a 2-dimensional view of a complex 3-dimensional structure. The purpose of this study was to confirm morphologically the radiographic appearance of anomalous coronary arteries and to construct a protocol for rapid determination of their true course. Twenty-one adults who had anomalous origin of coronary arteries without other evidence of congenital heart disease were reviewed. Using an anatomically correct model of the heart, solder wire was placed in the pathologically described anomalous positions and radiographed. With this model the pathologically described courses could be easily recognized and separated radiographically. These courses were confirmed in the operating room in 2 patients and a rare anomaly of posterior origin of a coronary artery was also confirmed by autopsy.

Tissue plasminogen activator followed by percutaneous transluminal coronary angioplasty: one-year TIMI phase II pilot results. TIMI Investigators.

The TIMI phase II pilot study enrolled 288 patients with acute myocardial infarction who were treated with recombinant tissue plasminogen activator (rt-PA) within 4 hours of symptom onset and who were assigned to coronary angioplasty of the infarct-related vessel 18 to 48 hours after rt-PA treatment. The patients were followed to ascertain (1) vital status; (2) whether they suffered a recurrent myocardial infarction; (3) whether they received coronary angioplasty or bypass grafting; and (4) whether they were rehospitalized for a cardiac event. Risk factors for these events or combination of these events were identified and reported. The estimated 6-week, 6-month, and 1-year cumulative event rate of death or myocardial infarction was 9.1 +/- 1.7%, 12.9 +/- 2.0%, and 13.6 +/- 2.0%, respectively. With the exception of repeat hospital admissions, most of the above cardiac events occurred early during the patients' follow-up course. Cox proportional hazard analyses revealed that continuing chest pain after rt-PA administration, history of congestive heart failure, low systolic blood pressure at the time of initial evaluation, and history of hypertension increased the risk of death or recurrent myocardial infarction, while a history of chest discomfort at baseline evaluation and older age was predictive of future hospitalization or a revascularization procedure.

Relation of silent myocardial ischemia after coronary artery bypass grafting to angiographic completeness of revascularization and long-term prognosis.

The prevalence and characteristics of silent myocardial ischemia as detected by 24-hour ambulatory electrocardiography ST-segment depression were prospectively assessed in 94 patients examined early (1 to 3 months) and 184 patients examined late (12 months) after coronary artery bypass grafting (CABG), and followed for a mean of 48 +/- 11 (range 4 to 62) months. The relation of ambulatory electrocardiographic silent ischemia to evidence of completeness of revascularization as defined by cardiac angiography performed 1 and 12 months after CABG, and to prognosis by follow-up of adverse clinical events was analyzed. Silent ischemia was detected early in 20% (19 of 94) and late in 27% (50 of 184) of patients, and showed a mean frequency of episodes ranging from 6 to 10 episodes/24 hours with a mean duration ranging from 15 to 23 minutes. The circadian distribution of episodes disclosed a significant peak of ischemic activity during the period of 6 A.M. to noon and a secondary peak between 6 P.M. and midnight (p less than 0.01 and p less than 0.001, respectively). Silent ischemia was not found by univariate analysis to be associated with graft or anastomotic site occlusions, low graft flow rates, grafted arteries with significant distal residual stenoses or ungrafted stenotic native coronary arteries. Kaplan-Meier analysis of time to cardiac event showed that silent ischemia was not predictive of an adverse clinical event in the early years after CABG. Cox regression analysis of 30 covariates only disclosed age (relative risk 1.06 [95% confidence interval, 1.01 to 2.94]) as having an effect on time to adverse clinical event.(ABSTRACT TRUNCATED AT 250 WORDS)