Exercise standards for testing and training: a statement for healthcare professionals from the American Heart Association.
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Adolescent↗
Biomedical subjects
B Chaitman
Publications and source records attributed to B Chaitman.
Moving toward a new definition of acute myocardial infarction for the 21st century: status of the ESC/ACC consensus conference. European Society of Cardiology and American College of Cardiology.
The European Society of Cardiology and American College of Cardiology established their initial Joint Consensus Conference in July 1999 to develop a new definition of Acute Myocardial Infarction. This action was deemed necessary because of the development of new sensitive biochemical markers of myocardial necroses: Troponins T and I. There were 5 working groups, including one in Electrocardiography. The Conference adopted a definition that required only a history of "ischemic symptoms" and "a typical rise and fall" of at least one of the biochemical markers. The ECG Working Group strongly advised that a term distinctive from "myocardial infarction" such as "myocardial necrosette" be adopted as the diagnosis for an acute coronary event during which the peak biochemical marker level is below that which occurs when serial evolutionary ECG changes are observed. A pilot substudy from the GUSTO IIa Clinical Trial has identified the low end of the "ECG Change Range" to be: >2x the upper limit of normal for CK-MB, > 11 x for Troponin T, and >6 x for Troponin I.
Creatine Kinase↗
Effect of transient abrupt vessel closure during otherwise successful angioplasty for unstable angina on clinical outcome at six months. Hirulog Angioplasty Study Investigators.
OBJECTIVES: The objective of this study was to identify predictors of major adverse cardiac events after successful coronary angioplasty. BACKGROUND: The acute complications of angioplasty are related to baseline clinical and angiographic variables, and early complications adversely affect long-term outcome. However, the predictors of enduring success after uncomplicated angioplasty are less well defined. METHODS: Of 4,098 patients undergoing angioplasty in the Hirulog Angioplasty Study, 3,899 (95%) had a successful procedure without in-hospital death, emergent bypass surgery or clinical evidence of myocardial infarction. Baseline and procedural variables for these 3,899 patients were examined. RESULTS: Major adverse cardiac events occurred in 22% of the patients with initially successful procedures at 6 months: death in 1%, myocardial infarction in 2% and repeat revascularization in 21%. Univariable predictors of increased events included successful salvage from abrupt vessel closure (p < 0.001), emergency stenting (p < 0.001), multilesion angioplasty (p < 0.001), diabetes (p=0.02), target lesion in the left anterior descending artery (p=0.02), unstable angina (p=0.03) and smaller final luminal diameter (p=0.04). There was a trend toward increased events among patients with prior angioplasty (p=0.08), but asymptomatic elevation of the creatine kinase was not predictive (p=0.5). In a multivariable model, abrupt vessel closure was the strongest independent predictor of major adverse cardiac events at 6 months (p < 0.001; odds ratio [95% confidence interval]=3.6 [2.5 to 5.1]), while multivessel angioplasty, target lesion in the left anterior descending artery and diabetes also remained independent predictors (all p < or = 0.02). CONCLUSIONS: This analysis suggests that "uncomplicated" abrupt vessel closure is a powerful predictor of adverse clinical outcome following successful angioplasty. Improved techniques to reduce abrupt closure during angioplasty are thus urgently needed, and patients who experience "uncomplicated" closure require closer surveillance during follow-up.
Aged↗
Factors associated with failure of medical therapy in patients with unstable angina and non-Q wave myocardial infarction. A TIMI-IIIB database study.
CONTEXT: Current management of patients with unstable angina and non-Q wave myocardial infarction generally consists of intensive medical therapy, with angiography and revascularization sometimes limited to those who fail such therapy. AIM: To determine if certain baseline characteristics are predictive of patients who fail medical therapy, since such patients could then be expeditiously directed to a more invasive strategy in a cost-effective manner. METHODS: The study cohort consisted of the 733 patients in the Thrombolysis in Myocardial Ischemia (TIMI) IIIB study who were randomized to conservative strategy. Patients were to be treated with bedrest, anti-ischaemic medications, aspirin, and heparin, and were to undergo risk-stratifying tests, consisting of an exercise test with ECG and thallium scintigraphy, scheduled to be performed within 3 days prior to, or 5 days after, hospital discharge and 24 h Holter monitoring scheduled to begin 2-5 days after randomization. Baseline clinical and ECG characteristics were compared between patients who 'failed' medical therapy and those who did not 'fail'. Failure was defined using clinical end-points (death, myocardial infarction, or spontaneous ischaemia by 6 weeks after randomization) or a strongly positive risk-stratifying test. For each test an ordered failure profile of results was calculated and consisted of death, myocardial infarction, or rest ischaemia occurring prior to performance of the test, a markedly abnormal test result, and no abnormality. RESULTS: Clinical end-points occurred in 241 (33%) patients and were more likely to occur in patients who at presentation were older, had ST-segment depression on the qualifying ECG, or were being treated with heparin or aspirin. Characteristics independently predictive of developing a clinical event or an abnormal exercise treadmill test included: ST-segment depression on the qualifying ECG, history of prior angina, family history of premature coronary disease (i.e. onset <55 years of age), prior use of heparin or aspirin, and increasing age. By combining these baseline risk characteristics for each outcome the incidence of developing a clinical event ranged from 8% if none was present to 63% if all six were present, and of developing a markedly abnormal risk stratifying test from 8-21% if none were present to approximately 90% if all six were present. CONCLUSIONS: Baseline characteristics associated with developing a clinical event or a markedly abnormal risk stratifying test were similar: rest anginal episode accompanied by ST-segment depression and occurring despite treatment with aspirin and heparin, a history of angina, older age, and family history of coronary disease. Patients with these characteristics are appropriate candidates for expeditious cardiac catheterization and consideration for revascularization, while patients without them may be suitable for medical management alone.
Aged↗
Heterogeneity among cardiac ischemic and anginal responses to exercise, mental stress, and daily life.
The objectives of this study were to compare and contrast indicators of ischemia in a well-characterized group of 196 patients with coronary artery disease, documented angiographically or by verified history of myocardial infarction, and a positive exercise test result. Myocardial ischemia occurs frequently in response to everyday stressors in patients with coronary artery disease. The Psychophysiological Interventions in Myocardial Ischemia study provides a unique opportunity to study neuroendocrine and psychological manifestations of ischemia. Patients with exercise-induced ischemia underwent exercise radionuclide ventriculography and electrocardiographic monitoring and 2 laboratory mental stressors (Speech and Stroop) after being withdrawn from cardiac medications. In addition, 48-hour ambulatory electrocardiograms were recorded during routine daily activities. Patients with a history of angina within the past 3 months reported angina during the bicycle or treadmill test with a much higher frequency than patients without such an anginal history (77% vs 26%). Ejection fraction (EF) responses to the Stroop test were abnormal in 48% of patients with an abnormal EF response to the Speech task, versus 17% in patients with a normal EF response (p <0.01). Seventy-six percent of patients had an abnormal EF response to bicycle exercise. Three indicators of ischemia (ST-segment depression, wall motion abnormality, and EF response) were compared during the same laboratory stressor and across different types of stress tests. Presence of the 3 indicators was only moderately associated during exercise, and only weak or nonsignificant associations occurred among the presence of the 3 ischemic markers during mental stress. Occurrence of the same ischemic markers was moderately associated between the 2 mental stress tasks, but few associations were found between the occurrence of the same ischemic marker during exercise and mental stress. There is a marked heterogeneity of responses to psychological and exercise stress testing using electrocardiography, ambulatory electrocardiography, or radionuclide criteria for ischemia during stress. The heterogeneity may be related to differences in the magnitude or types of physiologic responses provoked and to differences in the sensitivity and specificity of the different tests used to identify ischemia.
Aged↗
Recommendations for cardiovascular screening, staffing, and emergency policies at health/fitness facilities.
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Cardiovascular Diseases↗
Identifying high yield sources of patients with coronary artery disease for clinical trials: lessons from the Asymptomatic Cardiac Ischemia Pilot (ACIP) experience. The ACIP Study Group.
BACKGROUND AND HYPOTHESIS: Successful recruitment strategies for ischemic heart disease (IHD) clinical trials must identify high yield sources and efficient methods for selecting patients likely to have coronary artery disease (CAD) and ischemia, but such information is lacking. METHODS: Data from the recently completed Asymptomatic Cardiac Ischemia Pilot (ACIP) Trial were used as a model contemporary CAD/IHD trial to determine the relative patient yields, within a specific time frame, for various recruitment sources. RESULTS: Over 15 months, a total of 88,881 patient records was screened at 10 sites. The highest yield source was found by screening records of patients directly referred by a physician for possible study entry. This source accounted for 595 of 814 or 73% of potential patients and for 30% of patients eventually randomized. The largest volume of potential patients was observed from coronary angiographic laboratory record screening, and this source accounted for 39% (n = 7.542) of potential patients and for 24% of those randomized. The exercise electrocardiography (ECG) laboratory patient records yielded only 16% (5,340/33,784) of potential patients and 35% of patients randomized, but this source required considerably more time and resources for screening. CONCLUSION: Considering that time and resources for screening are fixed by budget in any trial, there is a need to balance high volume-moderate yield sources with low volume-high yield sources in order to optimize recruitment in future larger scale trials, and these data provide information and direction to focus such screening efforts.
Coronary Disease↗
Analyses of coronary graft patency after aprotinin use: results from the International Multicenter Aprotinin Graft Patency Experience (IMAGE) trial.
OBJECTIVE: We examined the effects of aprotinin on graft patency, prevalence of myocardial infarction, and blood loss in patients undergoing primary coronary surgery with cardiopulmonary bypass. METHODS: Patients from 13 international sites were randomized to receive intraoperative aprotinin (n = 436) or placebo (n = 434). Graft angiography was obtained a mean of 10.8 days after the operation. Electrocardiograms, cardiac enzymes, and blood loss and replacement were evaluated. RESULTS: In 796 assessable patients, aprotinin reduced thoracic drainage volume by 43% (P < .0001) and requirement for red blood cell administration by 49% (P < .0001). Among 703 patients with assessable saphenous vein grafts, occlusions occurred in 15.4% of aprotinin-treated patients and 10.9% of patients receiving placebo (P = .03). After we had adjusted for risk factors associated with vein graft occlusion, the aprotinin versus placebo risk ratio decreased from 1.7 to 1.05 (90% confidence interval, 0.6 to 1.8). These factors included female gender, lack of prior aspirin therapy, small and poor distal vessel quality, and possibly use of aprotinin-treated blood as excised vein perfusate. At United States sites, patients had characteristics more favorable for graft patency, and occlusions occurred in 9.4% of the aprotinin group and 9.5% of the placebo group (P = .72). At Danish and Israeli sites, where patients had more adverse characteristics, occlusions occurred in 23.0% of aprotinin- and 12.4% of placebo-treated patients (P = .01). Aprotinin did not affect the occurrence of myocardial infarction (aprotinin: 2.9%; placebo: 3.8%) or mortality (aprotinin: 1.4%; placebo: 1.6%). CONCLUSIONS: In this study, the probability of early vein graft occlusion was increased by aprotinin, but this outcome was promoted by multiple risk factors for graft occlusion.
Adult↗
Statement on exercise: benefits and recommendations for physical activity programs for all Americans. A statement for health professionals by the Committee on Exercise and Cardiac Rehabilitation of the Council on Clinical Cardiology, American Heart Association.
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Adult↗
Clinical outcome of deferring angioplasty in patients with normal translesional pressure-flow velocity measurements.
OBJECTIVES: The objective of this study was to determine the feasibility, safety and outcome of deferring angioplasty in patients with angiographically intermediate lesions that are found not to limit flow, as determined by direct translesional hemodynamic assessment. BACKGROUND: The clinical importance of some coronary stenoses of intermediate angiographic severity frequently requires noninvasive stress testing. Direct translesional pressure and flow measurements may assist in clinical decision making in patients with such stenoses. METHODS: Translesional spectral flow velocity (Doppler guide wire) and pressure data were obtained in 88 patients for 100 lesions (26 single-vessel and 74 multivessel coronary artery lesions) with quantitative angiographic coronary narrowings (mean +/- SD diameter narrowing 54 +/- 7% [range 40% to 74%]). Target lesion angioplasty was prospectively deferred on the basis of predetermined normal values, defined as a proximal/distal velocity ratio < 1.7 or a pressure gradient < 25 mm Hg, or both. Patients were followed up for 9 +/- 5 months (range 6 to 30). RESULTS: In the deferred angioplasty group, translesional velocity ratios were similar to those of a normal reference group (mean 1.1 +/- 0.32 vs. 1.3 +/- 0.55) and significantly lower than those of a reference cohort of patients who had undergone angioplasty (2.27 +/- 1.2, p < 0.05). The mean translesional pressure gradient in the deferred angioplasty group was also lower than that in the angioplasty group (10 +/- 9 vs. 45 +/- 22 mm Hg, p < 0.001). At follow-up in the deferred angioplasty group, four, six, zero and two patients, respectively, had had subsequent angioplasty, coronary artery bypass graft surgery or myocardial infarction or had died. In one patient, death was related to angioplasty of a nontarget artery lesion, and one patient with multivessel disease had a cardiac arrest due to ventricular fibrillation 12 months after lesion assessment. Among the 10 patients requiring later angioplasty or coronary artery bypass grafting, only six procedures were performed on target arteries. No patient had a complication of translesional flow or pressure measurements. CONCLUSIONS: These data demonstrate the safety, feasibility and clinical outcome of deferring angioplasty of coronary artery narrowings associated with normal translesional coronary hemodynamic variables. Given the practice of performing angioplasty without ischemic testing or when testing is inconclusive, translesional hemodynamic data obtained at diagnostic catheterization can identify patients in whom it is safe to postpone angioplasty.
Aged↗
Comparison of 15-year survival for men and women after initial medical or surgical treatment for coronary artery disease: a CASS registry study. Coronary Artery Surgery Study.
OBJECTIVES: This study compared the rates of coronary artery bypass graft surgery and 15-year survival for men and women after initial medical or surgical management. BACKGROUND: There has been concern that women with coronary artery disease are managed differently than men and that men and women have a different prognosis. The Coronary Artery Surgery Study (CASS) registry is a large data base of well characterized patients with long-term follow-up. METHODS: Patients underwent cardiac catheterization at 1 of 15 hospitals during 1974 to 1979. Bypass surgery rates were based on 12,452 men and 2,366 women. Survival results were based on 6,018 men and 1,095 women with operable coronary artery disease and initial medical management and 6,922 men and 1,291 women initially managed surgically. RESULTS: At 15 years, bypass surgery rates were 75% for men and 72% for women (p = 0.91). The rates remained similar after adjustment for clinical and angiographic variables. The 15-year survival rate was 50% for men and 49% for women with initial medical treatment (p = 0.53) and 52% for men and 48% for women (p = 0.004) with initial surgical treatment, a difference similar to that for operative mortality (men 2.5%, women 5.3%, p < 0.0001). Survival was improved by bypass surgery in most subgroups, with largest relative risks for high risk patients. Relative risks were similar for men and women. CONCLUSIONS: The rate of bypass surgery did not differ between men and women. There were few differences in the survival of men and women. In general, both men and women with initial surgical treatment survived longer, although benefits were clinically and statistically significant only in those at high risk. The benefit was similar in both men and women.
Cardiac Catheterization↗
Clinical and arteriographic characterization of patients with unstable angina without critical coronary arterial narrowing (from the TIMI-IIIA Trial).
Previous studies have reported that some patients presenting with unstable angina are found at coronary angiography to have no critical coronary stenosis. This study evaluated the clinical presentation and arteriographic findings in patients enrolled in the Thrombolysis in Myocardial Ischemia (TIMI-IIIA) trial, which assessed the effect of tissue-type plasminogen activator added to conventional therapy on the coronary arteriographic findings in patients presenting with ischemic pain at rest. Three hundred ninety-one patients were enrolled in the TIMI-IIIA trial and underwent coronary arteriography within 12 hours of enrollment. Fifty-three patients (14%) had no luminal diameter stenosis of a major coronary artery of > or = 60% on the baseline arteriogram. Compared with patients with unstable angina with an identifiable culprit lesion, patients without critical coronary obstruction were more likely to be women and non-white and less likely to have ST-segment deviation on the presenting electrocardiogram. Arteriography in such patients revealed no visually detectable coronary stenosis in half of the group; the remaining patients had noncritical coronary narrowing (i.e., < 60% luminal diameter stenosis) without morphologic features (ulceration or thrombus) suggestive of unstable or active coronary plaque. Nearly one third of the patients without critical coronary stenosis had impaired angiographic filling, suggesting a possible pathophysiologic role for coronary microvascular dysfunction. These patients with unstable angina and no critical coronary obstruction had an excellent short-term prognosis; 2% died or had myocardial infarction compared with 18% of patients with critical obstruction.
Angina, Unstable↗
Mechanisms of early death despite thrombolytic therapy: experience from the Thrombolysis in Myocardial Infarction Phase II (TIMI II) study.
Mechanisms of death among patients who died within 18 h of enrollment in the Thrombolysis in Myocardial Infarction Phase II (TIMI II) study were analyzed. Of 3,339 patients enrolled, 32 died within the 1st 4 h and 31 died within the subsequent 14 h. Thirteen of the 63 patients had shock at enrollment; 22 had advanced hemodynamic compromise without shock and 28 initially had minimal to no compromise. Prior infarction was present in 16 patients (25%). Pump failure was responsible for 39 early deaths (62%), ventricular rupture for 10 (16%), arrhythmia for 8 (13%) and complications of therapy for 6 (10%). Nine of 720 patients randomized to immediate intravenous beta-adrenergic blocking agent therapy had an early death compared with 6 of 714 assigned to deferred beta-blocker therapy. Thus, mortality is highest in the early hours after myocardial infarction, even in patients treated with thrombolytic therapy and is most frequently due to pump failure. These results imply that efforts to reduce mortality during this critical time period should be directed at prevention, limitation or palliation of early pump failure.
Adrenergic beta-Antagonists↗
Statement on exercise. Benefits and recommendations for physical activity programs for all Americans. A statement for health professionals by the Committee on Exercise and Cardiac Rehabilitation of the Council on Clinical Cardiology, American Heart association.
Explore the source record for details and available documents.
American Heart Association↗
Double-blind, dose-response, placebo-controlled multicenter study of nisoldipine. A new second-generation calcium channel blocker in angina pectoris.
BACKGROUND: Nisoldipine is a potent 1:4 dihydropyridine calcium channel antagonist, and doses of 5 or 10 mg administered either once or twice daily have been claimed to exert antianginal effects. There is, however, little information regarding the dose-response relation and whether the drug exerts any consistent effects throughout the dosing interval. In this placebo-controlled, parallel-design study, the dose-response relation of monotherapy with nisoldipine administered twice daily was studied in patients with stable angina pectoris. METHODS AND RESULTS: Two hundred thirty-one patients received single-blind placebo for 2 weeks; of these, 185 patients who reproducibly stopped treadmill exercise because of angina of moderate severity and had greater than or equal to 1 mm ST segment depression during exercise and experienced an average of three episodes of anginal attacks per week were randomized in a double-blind manner to one of the four treatment groups: placebo (n = 48), nisoldipine 2.5 mg (n = 47), nisoldipine 5 mg (n = 44), or nisoldipine 10 mg (n = 46). Nisoldipine or placebo was administered twice daily for 4 weeks and symptom-limited exercise tests were repeated at 2 and 10-14 hours after the double-blind medication. One hundred sixty-eight patients completed the study and 181 patients were valid for efficacy analysis. Compared with double-blind placebo, there were marginally significant trends toward increases for time to onset of angina for the 10-mg-b.i.d. group (83 versus 108 seconds, p = 0.08), time to 1 mm ST segment depression for the 5-mg-b.i.d. group (54 versus 83 seconds, p = 0.08), and total exercise time for the 5- (30 versus 50 seconds, p = 0.10) and 10-mg-b.i.d. (30 versus 58 seconds, p = 0.06) groups at 2 hours after the dose (peak effect) after 4 weeks of therapy. At 10-14 hours after the dose (trough effect), no differences between placebo and any of the nisoldipine doses on any of the exercise parameters were found after 4 weeks of therapy. A subset analysis of patients who stopped exercise within 10 minutes because of angina of moderate severity during single-blind placebo therapy (n = 123) revealed significant increase in total exercise duration and time to 1 mm ST segment depression at 2 hours after the dose in the 5- and 10-mg-b.i.d. dose groups compared with double-blind placebo (p less than 0.04). No significant trough effects, however, were observed even in this subgroup after any of the doses of nisoldipine. The frequency of anginal attacks decreased by 44%, 41%, 30%, and 41% after twice-daily therapy with 2.5 mg, 5 mg, 10 mg nisoldipine, and placebo groups, respectively (p = NS, nisoldipine versus placebo). The incidence of adverse events (minor and major) was 43.8% in the placebo group and 42.6%, 45.5%, and 56.5% in the nisoldipine 2.5-, 5-, and 10-mg-b.i.d. groups, respectively (p = NS compared with placebo). However, four patients developed unstable angina while on nisoldipine therapy (two in the 2.5-mg, one in the 5-mg, and one in the 10-mg-b.i.d. group) and two patients died suddenly in the nisoldipine 10-mg-b.i.d. group. CONCLUSIONS: Monotherapy with 2.5, 5, and 10 mg nisoldipine twice a day was not superior to placebo therapy in treating patients with angina pectoris, and the 10-mg-b.i.d. therapy resulted in a statistically insignificant but clinically important increase in the incidence of serious adverse events.
Adult↗
Percutaneous balloon valvuloplasty and coronary angioplasty for the treatment of calcific aortic stenosis and obstructive coronary artery disease in an elderly patient.
An 81-year-old man with severe calcific aortic stenosis and coronary artery disease who refused surgical therapy was treated with sequential percutaneous balloon aortic valvuloplasty (PBAV) and percutaneous transluminal angioplasty. Before percutaneous balloon valvuloplasty, the mean aortic gradient was 76 mmHg, and the aortic valve area was .45 cm2. The aortic valve was dilated using 15-mm and 18-mm balloons. The mean gradient decreased to 40 mmHG, and the aortic valve area increased to .62 cm2. Percutaneous transluminal coronary angioplasty (PTCA) was performed 2 weeks later, and an 85% proximal left circumflex stenosis was successfully dilated to 20%. No complications were noted during either procedure. At 6-month follow-up, the patient had returned to normal activities and was asymptomatic. Thus, combined therapy with PBAV and PTCA is technically feasible in selected elderly patients with calcific aortic stenosis and anatomically suitable coronary artery disease. This nonsurgical therapeutic approach may be useful in the treatment of selected patients who refuse or who are deferred from cardiac surgery.
Aged↗
Restenosis after multilesion percutaneous transluminal coronary angioplasty.
Experience and new technical advances have resulted in an increasing number of patients with multivessel coronary disease who can be considered for percutaneous transluminal coronary angioplasty (PTCA). In selected patients with multivessel coronary disease, PTCA is a safe and effective procedure for the immediate relief of anginal symptoms. However, many questions remain regarding the long-term therapeutic benefit of the procedure. Few data are available on the incidence and clinical significance of restenosis after multilesion PTCA. Clearly, there is the potential for a higher rate of restenosis in patients who undergo dilatation of more than 1 lesion. Determination of restenosis rates after multilesion PTCA is important in the definition of expanded indications for this procedure. Because of the variations in definitions of restenosis and in patient selection factors, reported recurrence rates after multilesion PTCA are not easily compared between patient series. After multilesion dilatation the risk of developing at least 1 recurrent lesion ranges from 26% to 53% and appears to be greater than that reported for single lesion PTCA. Multilesion restenosis occurs in 7% to 21% of patients who undergo multilesion PTCA and is frequently observed in patients with recurrent symptoms. "Silent" multilesion restenosis (i.e., multiple lesion restenosis without symptoms) is rare. A higher risk of restenosis at one of several dilatation sites in a patient with extensive coronary disease should not be a deterrent in recommending multilesion PTCA to selected patients with multivessel coronary disease because the procedure provides important symptomatic relief to most. Further, recurrent narrowings are usually amenable to a second dilatation attempt if clinically indicated.
Angioplasty, Balloon↗
The Thrombolysis in Myocardial Infarction (TIMI) phase II pilot study: tissue plasminogen activator followed by percutaneous transluminal coronary angioplasty.
The Thrombolysis in Myocardial Infarction (TIMI) Study Group is investigating whether percutaneous transluminal coronary angioplasty or intravenous beta-receptor blockers, or both, are useful adjuncts to recombinant tissue-type plasminogen activator (rt-PA) in the treatment of patients with acute myocardial infarction (TIMI II study). A total of 317 patients with acute myocardial infarction were treated an average of 2.7 hours after the onset of chest pain during the course of a nonrandomized pilot investigation with 150 mg of rt-PA given over 6 hours. This dose of rt-PA resulted in a high rate of infarct-related coronary artery patency (82 and 87% of patients catheterized an average of either 1 or 32 hours after entry, respectively) and a low 21 day mortality rate of 4.4%. Coronary angioplasty was performed successfully in greater than 90% of patients with appropriate anatomy and in greater than 50% of those treated with rt-PA. In 75 patients treated within 2 hours of the onset of chest pain only 2 (2.7%) were dead by 6 weeks. However, five cases of intracranial hemorrhage were noted, and the rt-PA dose was subsequently reduced to 100 mg given over 6 hours. The TIMI II design and the results of the TIMI II pilot study are discussed.
Adrenergic beta-Antagonists↗