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1.
2.
Severe thrombotic events following ovarian stimulation for in-vitrofertilization (IVF) procedures in three women are reported.None of these patients presented any concomitant clinical signof ovarian hyperstimulation syndrome. Coagulation inhibitorswere in the normal range but cardiovascular risk factors werepresent. It is postulated that early thrombosis could be favouredby high endogenous plasma oestrogen concentrations subsequentto ovarian stimulation when associated with another risk factor.Our data are discussed in relation to previous publications.It is suggested that risk factors must be considered individuallybefore each IVF attempt. In patients at high risk, clinicalmanagement of the post-transfer period is recommended.  相似文献   
3.

Background

Information on young patients with Brugada syndrome (BrS) and arrhythmic events (AEs) is limited.

Objectives

The purpose of this study was to describe their characteristics and management as well as risk factors for AE recurrence.

Methods

A total of 57 patients (age ≤20 years), all with BrS and AEs, were divided into pediatric (age ≤12 years; n = 26) and adolescents (age 13 to 20 years; n = 31).

Results

Patients’ median age at time of first AE was 14 years, with a majority of males (74%), Caucasians (70%), and probands (79%) who presented as aborted cardiac arrest (84%). A significant proportion of patients (28%) exhibited fever-related AE. Family history of sudden cardiac death (SCD), prior syncope, spontaneous type 1 Brugada electrocardiogram (ECG), inducible ventricular fibrillation at electrophysiological study, and SCN5A mutations were present in 26%, 49%, 65%, 28%, and 58% of patients, respectively. The pediatric group differed from the adolescents, with a greater proportion of females, Caucasians, fever-related AEs, and spontaneous type-1 ECG. During follow-up, 68% of pediatric and 64% of adolescents had recurrent AE, with median time of 9.9 and 27.0 months, respectively. Approximately one-third of recurrent AEs occurred on quinidine therapy, and among the pediatric group, 60% of recurrent AEs were fever-related. Risk factors for recurrent AE included sinus node dysfunction, atrial arrhythmias, intraventricular conduction delay, or large S-wave on ECG lead I in the pediatric group and the presence of SCN5A mutation among adolescents.

Conclusions

Young BrS patients with AE represent a very arrhythmogenic group. Current management after first arrhythmia episode is associated with high recurrence rate. Alternative therapies, besides defibrillator implantation, should be considered.  相似文献   
4.
Ventricular fibrillation in patients without recognizable heart disease is uncommon and electrophysiologic data on such patients is limited. Over a 7 year period, five patients (three men and two women, ranging in age from 24 to 52 years) without demonstrable heart disease underwent electrophysiologic studies with pharmacologic drug testing because of single (four patients) or multiple (one patient) documented episodes of ventricular fibrillation. The arrhythmic event was unrelated to myocardial ischemia or infarction, metabolic or electrolyte disturbances, drug toxicity, preexcitation, or prolonged QT syndromes. In all three patients receiving no antiarrhythmic drugs and in two pretreated with amiodarone, a rapid poorly tolerated ventricular tachyarrhythmia requiring cardioversion was induced by programmed ventricular stimulation with up to two extrastimuli. In all instances, addition of either oral quinidine or oral disopyramide prevented the induction of sustained ventricular arrhythmias. All five patients were placed on antiarrhythmic drug regimens found effective during electrophysiologic studies and remained asymptomatic during follow-up periods ranging from 12 to 93 (mean 52) months. We conclude that in the patients with idiopathic ventricular fibrillation in our study: programmed ventricular stimulation reliably replicated the spontaneous arrhythmia, class I antiarrhythmic agents effectively prevented induction of the arrhythmia in the laboratory, and in contrast to the severity of the presenting arrhythmia, a benign clinical course was observed during long-term therapy with class I antiarrhythmic agents.  相似文献   
5.
The sensitivity and specificity of a new protocol of programmed ventricular stimulation were evaluated in 71 consecutive patients who were divided into 2 groups: group 1 included 41 patients, of whom 25 had sustained ventricular tachycardia (VT) not associated with cardiac arrest and 16 had ventricular fibrillation (VF) not precipitated by any obvious factor; group 2 included 30 patients without demonstrable heart disease and no suspected or documented sustained ventricular tachyarrhythmias. The study consisted of a standard protocol (up to 2 extrastimuli given only once for each extrastimulus prematurity, 2 right ventricular sites and 3 basic pacing cycle lengths, as well as rapid ventricular pacing) in which double extrastimulation at the shortest coupling intervals that allowed ventricular capture was repeated 10 times. A stimulus current of 3 mA was used. Sustained ventricular tachyarrhythmias were induced in 23 of 25 (92%) patients who presented with sustained VT, 14 of 16 (88%) patients who presented with VF and 2 of 30 (7%) group 2 patients. Eighteen of 25 (72%) patients with sustained VT but only 4 of 16 (25%) with VF had arrhythmias inducible at "immediate" trials of single or double extrastimulation (p less than 0.01). Repetition of double extrastimulation increased the yield of inducible sustained ventricular tachyarrhythmia to 92% in patients with sustained VT (+20%, p = 0.14) and 75% (+50%, p = 0.013) in patients with VF. Rapid right ventricular pacing added a 13% increase in the overall yield in patients with VF. This new protocol of programmed ventricular stimulation has both high sensitivity (90%) and specificity (93%) for induction of sustained VT.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
6.
The cytomegalovirus (CMV) antigenemia assay has been used frequently for rapid diagnosis of CMV infection, and antigenemia threshold values are recommended for triggering preemptive therapy. Hybrid capture of CMV's DNA and quantitative polymerase chain reaction (qPCR) are increasingly being adopted for early detection of CMV. The performance of the antigenemia assay, qPCR in plasma and hybrid capture in leukocytes were compared in 110 immunocompromised patients (38 bone-marrow transplants, 50 renal transplants and 22 AIDS patients). The most sensitive test was hybrid capture for transplants, while antigenemia and the qPCR showed similar performance for patients with AIDS. QPCR and hybrid capture thresholds requiring antiviral therapy were calculated using a receiver-operating-characteristic curve for antigenemia values corresponding to 2 positive cells for bone-marrow transplants and to 10 positive cells for renal transplants and AIDS patients. These threshold values varied with the group of patients considered, with corresponding sensitivities higher than 86% and specificities higher than 76% for hybrid capture, and sensitivities higher than 61% and specificities higher than 75% for qPCR in plasma. Hybrid capture in leukocytes can substitute for antigenemia in the case of transplants, and qPCR in plasma can substitute for it in the case of AIDS patients.  相似文献   
7.
Transcatheter electrical shock ablation of a concealed posteroseptal accessory pathway was performed on a 57-year-old man with drug-refractory paroxysmal supraventricular tachycardia. A single 300-joules shock delivered at the ostium of the coronary sinus abolished conduction in the accessory pathway and resulted in long-term cure of the arrhythmia. No complications were observed during the procedure.  相似文献   
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9.
Flow-mediated vasodilation (FMD) of human blood vessels is essential to adaptation and regulation of peripheral blood flow, and is mediated by endogenously produced nitric oxide. Endothelial function is impaired in many pathologic states, especially in coronary heart disease. We questioned in this study whether exogenous nitric oxide (NO) would restore endothelial dysfunction in peripheral arteries of patients with coronary artery disease (CAD). In a randomized double-blinded case-control assay, we used computerized A-mode ultrasonography to measure diastolic diameters of the brachial artery before and after hyperemia in two groups of 10 patients with CAD. Each group received orally either placebo or 12 mg molsidomine a day for 48 h. In the molsidomine group, FMD was improved with a 60% increase after the first intake of molsidomine, and the same trend was observed after the last intake, although less pronounced. Significant increase in diastolic diameter was observed after the last molsidomine intake, but not after the first one. Thus molsidomine has an early positive effect on FMD in addition to a delayed vasodilator effect. Improvement of endothelial dysfunction by molsidomine in patients with CAD may uncover new therapeutic perceptive in the use of nitrovasodilators.  相似文献   
10.
The ability to detect coronary artery disease (CAD) in patients with normal, conventional electrocardiograms (ECG) was studied using high frequency electrocardiography and an advanced method of signal averaging in three groups of subjects. Group A consisted of ten healthy subjects under the age of 30; Group B of 15 patients with chest pains and normal coronary arteries; and Group C of 20 patients with chest pains and CAD. Four hundred ECG waveforms from leads V3, V4 and V5 were recorded, and the recorded analog data were digitized. The digitized waveforms were averaged using a cross-correlation function which operates in the frequency domain (fast-Fourier transform algorithm). The signals were filtered with a digital band pass filter with 150 and 250 Hz low and high cut-off frequencies, respectively. Zones of reduced amplitude in the envelope of the filtered QRS complex of at least two precordial leads were found more significantly in patients with CAD (75%) than in patients without CAD (12% for Groups A and B, p less than 0.00003). However, no significant difference was found between the voltage over the high frequency QRS complex and that of its envelope between the three groups. It is concluded that the morphology of the high frequency QRS complex as determined by this advanced method of analysis of the signal averaged ECG may be a useful indicator for the presence of CAD in patients with normal conventional ECG's.  相似文献   
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