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61.
Invoking unacceptable operative risks, many institutions have adopted a conservative policy toward carotid stenosis in patients who require cardiopulmonary bypass (CPB). We have continued to apply simultaneous carotid endarterectomy/coronary artery bypass grafting (CEA/CABG) in selected patients, and in order to place operative risk in perspective, our experience with CEA/CABG was reviewed and contrasted with both CEA and CABG performed as isolated procedures. Seventy-one CEA/CABG were performed from 1978 to 1987, with the bulk of the experience (51/71) accumulated over the past 5 years. CEA/CABG was applied when the carotid lesion was severe (greater than or equal to 75% diameter stenosis). Clinical characteristics of patients with CEA/CABG (e.g., presence of unstable angina, left main coronary artery disease, and impairment of ventricular function) suggested these patients were at higher risk for complications when compared to patients with CABG alone. Yet, other factors influencing stroke risk during cardiopulmonary bypass (patient age, duration of CPB time) were similar between patients with CEA/CABG and patients with only CABG. Most complications in patients with CEA/CABG occurred in the early years of the study. Considering the recent (1983-87) patient cohorts of CEA/CABG and isolated CABG, respectively, there was no significant difference in either operative mortality (2.0% as compared to 2.2%) or perioperative stroke (2.0% as compared to 0.6%). Whereas precise patient selection criteria remain undefined, these findings verify the safety of the combined CEA/CABG approach for most patients who require treatment of both lesions.  相似文献   
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Eight patients with a posteroseptal accessory pathway and symptomatic atrial fibrillation and/or orthodromic reciprocating tachycardia underwent attempted transcatheter ablation of the accessory pathway. A quadripolar electrode catheter was positioned within the coronary sinus such that the proximal pair of electrodes straddled the os. This proximal pair of electrodes was made electrically common and connected to the cathodal output of a defibrillator. A patch electrode placed over the midthoracic spine was connected to the anodal sink of the defibrillator. Two to three transcatheter shocks were delivered, with a cumulative energy of 600 to 900 J. Immediately after the shocks were delivered, retrograde accessory pathway conduction was absent in each patient. Anterograde conduction through the posteroseptal accessory pathway was absent in six patients. In one patient, retrograde accessory pathway conduction was absent and anterograde conduction was present but was slower than at baseline. In this patient, orthodromic tachycardia was no longer inducible and the ventricular rate during induced atrial fibrillation was 150 beats/min, compared with 220 beats/min before the attempted ablation. He has remained asymptomatic without antiarrhythmic drug therapy for 18 months. In one patient, the transcatheter shocks had no long-term effect on accessory pathway conduction. The shocks delivered at the os of the coronary sinus were well tolerated.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Adenosine was administered to test the hypothesis that it would maximize preexcitation and facilitate noninvasive localization of accessory pathways in 22 patients with suspected accessory pathway-mediated tachycardias. Twelve-lead electrocardiograms and 2-dimensional echocardiograms were recorded at baseline and during adenosine-augmented ventricular preexcitation to localize the accessory pathway. Phase analysis was performed on digitized 4-chamber and short-axis views using a first harmonic Fourier transformation. At baseline, 15 patients had manifest preexcitation. In 14 of these patients (93.3%), preexcitation became more prominent after adenosine. Four patients without preexcitation at baseline clearly had it after adenosine. In patients who had preexcitation in response to adenosine, the electrocardiogram correctly identified the accessory pathway locations in 18 of 19 patients at a regional level and was incorrect in 1 of 19 patients. Echocardiographic phase analysis correctly identified the accessory pathway location in all 17 patients, who had technically adequate studies, at a regional level. In conclusion, administration of adenosine accentuates preexcitation, allowing for more accurate electrocardiographic and echocardiographic accessory pathway localization.  相似文献   
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Avulsion of permanent teeth is one of the most serious dental injuries. Prompt and correct emergency management is essential for attaining the best outcome after this injury. The International Association of Dental Traumatology (IADT) has developed these Guidelines as a consensus statement after a comprehensive review of the dental literature and working group discussions. It represents the current best evidence and practice based on that literature search and expert opinions. Experienced researchers and clinicians from various specialties and the general dentistry community were included in the working group. In cases where the published data did not appear conclusive, recommendations were based on consensus opinions or majority decisions of the working group. They were then reviewed and approved by the members of the IADT Board of Directors. The purpose of these Guidelines is to provide clinicians with the most widely accepted and scientifically plausible approaches for the immediate or urgent care of avulsed permanent teeth. The IADT does not, and cannot, guarantee favorable outcomes from adherence to the Guidelines. However, the IADT believes that their application can maximize the probability of favorable outcomes.  相似文献   
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Fifty-six patients with acute myocardial infarction complicated by sinus bradycardia (SB) were treated with intravenous atropine and monitored in a coronary care unit. Atropine decreased or completely abolished premature ventricular contractions (PVCs) and/or bouts of accelerated idioventricular rhythm in 27 of 31 patients (87%) and brought systemic blood pressure up to normal in 15 of 17 patients (88%) with hypotension. In addition, atropine administration was associated with improved atrioventricular conduction in 11 of 13 patients (85%) with acute inferior myocardial infarction associated with 2 degrees or 3 degrees atrioventricular block. Seven patients developed ten significant adverse effects: ventricular tachycardia or fibrillation in three, sustainedsinus tachycardia in three, increased PVCs in three, and toxic psychosis in one. These major adverse effects correlated with either a higher initial dose of atropine (i.e., 1.0 mg aa compared with the usual 0.5 or 0.6 mg) or a total cumulative dose exceeding 2.5 mg over 21/2 hours. Atropine is the drug of choice for management of patients with SB and hypotension and is effective in the treatment of ventricular arrhythmias as well as conduction disturbances in patients with inferior myocardial infarction. Serious adverse effects, however, preclude use of atropine without careful medical supervision.  相似文献   
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