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A 73-year-old woman was studied after admission for anteriorwall ST-segment elevation myocardial infarction. Transthoracicechocardiography (GE Vingmed, Vivid 7, Horten, Norway)  相似文献   
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The class Ic antiarrhythmic agent propafenone was studied by repeated electrophysiologic testing in 54 patients (43 male, aged 54 +/- 10 years, mean ejection fraction of 37.3 +/- 16.9%) with ventricular tachyarrhythmias. Forty patients (74%) had coronary artery disease. Programmed ventricular stimulation (S2, S2S3 during sinus rhythm and/or during S1S1 = 500, 430, 370, and 330 ms) off antiarrhythmic drugs induced sustained ventricular tachycardia, flutter, or fibrillation in all patients. After 450-900 mg of oral propafenone/day for 4-7 days, 51 patients were restudied. In the remaining three patients, spontaneous ventricular tachycardia occurred on drug therapy. Tachycardia induction was suppressed in 9 of 51 patients restudied (18%) and rendered more difficult to induce (basic stimulation drive greater than or equal to 40 beats/min higher than at control study) in another 7 patients (14%) (overall efficacy of 31%). The tachycardia rate decreased from 220 +/- 43 to 177 +/- 44 beats/min (p less than 0.01). The right ventricular effective refractory period increased from 232 +/- 22 to 252 +/- 22 ms (p less than 0.001). Responders to propafenone therapy had higher rates of inducible ventricular tachycardia at control (greater than 230 beats/min: 43%; less than or equal to 230 beats/min: 21%; p less than 0.05), higher ejection fractions, and lower left ventricular end-diastolic pressures than nonresponders. Eleven of the 16 patients showing a positive response to propafenone therapy in electrophysiologic testing were discharged on propafenone alone. During follow-up (17 +/- 12 months), nine patients remained free from ventricular tachycardia, one patient had a relapse, and one patient died of noncardiac death.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Between June 1978 and 1986, 93 consecutive patients underwent electrophysiologically guided operations for life-threatening recurrent sustained ventricular tachycardia mostly associated with other surgical procedures, such as left ventricular resection (aneurysmectomy) and coronary artery bypass grafting. Data: Eighty-seven percent of the surviving patients were free of spontaneous ventricular tachycardia return or sudden death 1 year after the operation and 77% at 5 years. The instantaneous risk of ventricular tachycardia return was highest immediately after operation, declined rapidly, and by 2 weeks postoperatively had merged with the constant hazard phase, which persisted as long as the patients were observed. Endocardial resection, rather than encircling endocardial myotomy, increased the risk of spontaneous ventricular tachycardia return/sudden death. Survival rates, including hospital deaths, were 95% at 30 days, 89% at 1 year, and 70% at 5 years after operation. The most prevalent mode of death was heart failure. The absence of anterolateral left ventricular aneurysms and the use of more extended encircling incisional techniques for ventricular tachycardia ablation increased the risk of early and late death. Survival was particularly poor in that subset of patients in whom recurrent sustained ventricular tachycardia returned after operation; the most prevalent mode of death in this group was also progressive left ventricular failure. Inferences: (1) Complete and partial encircling endocardial myotomy incisions are the most effective surgical techniques for malignant ventricular tachycardia ablation. (2) Because of their adverse effects on left ventricular structure and function, the arrhythmogenic tissues have to be localized as precisely as possible, and the encompassing incisions should be kept as limited as possible. (3) The late return of ventricular tachycardia may be more related to a progressive ischemic left ventricular cardiomyopathy than to an inadequate operation.  相似文献   
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369 (63%) of 586 consecutive patients with confirmed myocardial infarction were admitted to hospital within 6 h of symptom onset. Patients' arrival to hospital followed a characteristic circadian distribution with a marked morning increase between 0600 and 1200 hours, and a corresponding decrease in the late night hours. There were no differences in the occurrence of late potentials and in ECG data between early and late arrival group. The early group (less than 5.9 h) was, however, characterized by significantly higher cardiac enzyme levels than the late group (greater than 6.0 h); they also experienced more arrhythmic events in the acute phase (16.0% vs. 9.7%; p less than 0.032). Catecholamines were significantly more often necessary (26.4% vs. 10.3%; p less than 0.0001). Six-month prognosis after AMI was markedly worse. The time between symptom onset and hospital arrival was not affected by age and risk factors. In univariate analysis, pain history and recurrent infarction also had no influence on delay of admission to hospital. The time interval was, however, significantly shorter when the acute event occurred during the night (18.4% vs. 8.3%; p less than 0.0001). Absence of prodromi in the prehospital phase (18.5% vs. 12.0%; p less than 0.04) and a higher socio-economic level (68.3% vs. 61.0%; p less than 0.077) also shortened the admission time, whereas a hyperactive behavioral pattern prolonged the delay time (21.1% vs. 28.9%; p less than 0.05).  相似文献   
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Oscillatory motion of the normal cervical spinal cord   总被引:2,自引:0,他引:2  
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In supplementation of previously published cardiac sodium channel (SCN5A) gene mutations that were cited in the text, in Table 2 and in Figure 2 we here apply an updated gene mutation nomenclature (Human Genome Variation Society, 2005) to facilitate mutation annotation comparison (SCN5A cDNA reference: NM_198056.1 or GI: 37622906; amino acid reference sequence: SWISS‐PROT entry Q14524, long splice variant, 2,016 amino acids): Mutation: c.2602delC Amino acid change: p.Glu868X Mutation: c.2581_2582delTT Amino acid change: p.Phe861Trp fsX90 Mutation: c.4477_4479delAAG Amino acid change: p.Lys1493del Mutation: c.5425C>A Amino acid change: p.Ser1812X  相似文献   
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It has previously been shown that, in the heterozygous state, mutations in the SOX9 gene cause campomelic dysplasia (CD) and the often associated autosomal XY sex reversal. In 12 CD patients, 10 novel mutations and one recurrent mutation were characterized in one SOX9 allele each, and in one case, no mutation was found. Four missense mutations are all located within the high mobility group (HMG) domain. They either reduce or abolish the DNA-binding ability of the mutant SOX9 proteins. Among the five nonsense and three frameshift mutations identified, two leave the C-terminal transactivation (TA) domain encompassing residues 402-509 of SOX9 partly or almost completely intact. When tested in cell transfection experiments, the recurrent nonsense mutation Y440X, found in two patients who survived for four and more than 9 years, respectively, exhibits some residual transactivation ability. In contrast, a frameshift mutation extending the protein by 70 residues at codon 507, found in a patient who died shortly after birth, showed no transactivation. This is apparently due to instability of the mutant SOX9 protein as demonstrated by Western blotting. Amino acid substitutions and nonsense mutations are found in patients with and without XY sex reversal, indicating that sex reversal in CD is subject to variable penetrance. Finally, none of 18 female patients with XY gonadal dysgenesis (Swyer syndrome) showed an altered SOX9 banding pattern in SSCP assays, providing evidence that SOX9 mutations do not usually result in XY sex reversal without skeletal malformations.   相似文献   
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