Circulation
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Randomized Controlled Trial Clinical Trial
Starting aspirin therapy after operation. Effects on early graft patency. Department of Veterans Affairs Cooperative Study Group.
Although aspirin therapy started before operation improves vein graft patency after coronary artery bypass grafting, it also causes bleeding. The objective of this prospective, centrally directed, randomized, double-blind, placebo-controlled trial was to compare the effects of aspirin therapy started before operation with aspirin started 6 hours after operation on early (7-10-day) graft patency. ⋯ Thus, preoperative aspirin is associated with increased bleeding complications and offers no additional benefit in early vein graft patency compared with starting aspirin therapy 6 hours after operation. There was a trend, although not significant, toward improved early patency for Y grafts and internal mammary artery grafts with preoperative aspirin.
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Randomized Controlled Trial Multicenter Study Comparative Study Clinical Trial
Intracerebral hemorrhage, cerebral infarction, and subdural hematoma after acute myocardial infarction and thrombolytic therapy in the Thrombolysis in Myocardial Infarction Study. Thrombolysis in Myocardial Infarction, Phase II, pilot and clinical trial.
In the Thrombolysis in Myocardial Infarction, Phase II pilot and clinical trial, 908 patients [326 (35.9%) in the pilot study and 582 (64.0%) in the randomized study] were treated with 150 mg recombinant tissue-type plasminogen (rt-PA) activator in combination with heparin and aspirin, and 3,016 patients [64 (2.1%) in the pilot study and 2,952 (97.9%) in the randomized study] were treated with 100 mg rt-PA in combination with heparin and aspirin. Adverse neurological events occurred in 23 patients treated with 150 mg rt-PA (2.5%) [nine cerebral infarctions (1.0%), 12 intracerebral hemorrhages (1.3%), and two subdural hematomas (0.2%)] and in 33 patients treated with 100 mg rt-PA (1.1%) [20 cerebral infarctions (0.7%), 11 intracerebral hemorrhages (0.4%), and two subdural hematomas (0.1%)]. The difference in adverse neurological events observed comparing the two rt-PA regimens was primarily due to a higher frequency of intracerebral bleeding among patients treated with 150 mg rt-PA (1.3% versus 0.4%, p less than 0.01). ⋯ Mortality at 6 weeks after presentation among 23 patients who had intracerebral hemorrhage was 47.8%. Intracerebral hemorrhage is a severe but infrequent complication of rt-PA therapy for acute myocardial infarction. The combined frequency of intracerebral hemorrhage, subdural hematoma, and cerebral infarction after treatment with 100 mg rt-PA is comparable to that observed in other trials with thrombolytic agents in acute myocardial infarction.
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Randomized Controlled Trial Comparative Study Clinical Trial
Nifedipine reduces the incidence of myocardial infarction and transient ischemia in patients undergoing coronary bypass grafting.
A randomized study was performed on 104 patients undergoing elective coronary artery bypass grafting to examine whether the infusion of nifedipine (n = 53) reduces the incidence of perioperative myocardial ischemia and necrosis in the early postoperative period. Continuous hemodynamic and three-channel Holter monitoring was performed for 24 hours and serial assessment of serum enzymes and 12-lead electrocardiography were performed for 36 hours postoperatively. Nifedipine (minimum dose, 10 micrograms/kg/hr for 24 hours) was applied from the onset of extracorporal circulation. ⋯ Using the combined analyses of electrocardiography and Holter recordings, myocardial ischemia was defined as being either a transient ischemic event (TIE), transient coronary spasm (TCS), or myocardial infarction (MI). The two groups did not differ with respect to preoperative New York Heart Association classification, age, history of myocardial infarction, extracorporal circulation and aortic cross-clamp time, number of distal anastomoses, or systemic and pulmonary hemodynamics. The incidence of perioperative myocardial ischemia was substantially lower in the nifedipine than in the nitroglycerin group [TIE: three of 53 patients (6%) versus nine of 50 patients (18%), p less than 0.001; MI: two of 53 patients (4%) versus six of 50 patients (12%), p less than 0.001; and TCS: none of 53 patients (0%) versus two of 50 patients (4%), p = NS].(ABSTRACT TRUNCATED AT 250 WORDS)
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Randomized Controlled Trial Comparative Study Clinical Trial
Flecainide acetate prevents recurrence of symptomatic paroxysmal supraventricular tachycardia. The Flecainide Supraventricular Tachycardia Study Group.
Oral flecainide acetate was administered to 34 patients with documented symptomatic paroxysmal supraventricular tachycardia (PSVT) with a double-blind, placebo-controlled, 8-week crossover trial design. PSVT was defined as a regular tachycardia of at least 120 beats/min without evidence of atrioventricular dissociation. The study required considerable patient cooperation. ⋯ The median time to the first symptomatic PSVT event was 11 days in the placebo group and greater than 55 days in the flecainide group (p less than 0.001). Likewise, the interval between attacks was a median of 12 days on placebo compared with more than 55 days on flecainide (p less than 0.001). Finally, the flecainide slowed symptomatic PSVT heart rates to 143 +/- 12 beats/min from 178 +/- 12 on placebo (p less than 0.02) in the seven patients who had events in the placebo and flecainide treatment phases.(ABSTRACT TRUNCATED AT 250 WORDS)
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Review Randomized Controlled Trial Clinical Trial
Routine medical management of acute myocardial infarction. Lessons from overviews of recent randomized controlled trials.
In recent years, several large randomized trials have clarified the role of various interventions in acute myocardial infarction. There is clear evidence that thrombolytic therapy, aspirin, and beta-blockers reduce mortality. Both aspirin and beta-blockers also reduce reinfarction and stroke. ⋯ Heparin increases the risk of hemorrhagic complications twofold. Although trials of vasodilators conducted before the widespread use of thrombolytic therapy and aspirin have been promising, newer trials are needed to evaluate their effects among patients receiving these agents. The aggregate of all trials of the routine use of calcium antagonists or antiarrhythmic agents indicates that these agents do not improve survival.