Biomedical subjects
Publications and source records attributed to J Victor.
Injuries to the extensor mechanism of the knee require a profound rehabilitation. The authors present a case in which postsurgical weakening was complicated by quadriceps tendon rupture.
The authors report a new case of digitoxin-related thrombocytopenia. It involved a patient hospitalised for torsades de pointe in whom blood digitoxin was 85 micromols/l on admission. This rare complication progressed to a satisfactory conclusion in seven days. The mechanism is immuno-allergic and/or toxic since thrombocytopenia occurs only following therapeutic overdose. The prognosis is determined by the cardiac arrhythmia rather than the hemostasis abnormality. Treatment is symptomatic and should include the withdrawal of digitoxin which can be replaced by digoxin. Oral activated charcoal decreases the plasma half-life by blocking the enterohepatic cycle and is hence recommended in this situation.
A hereditary form of multicentric osteolysis is described in an 11-year-old girl whose father is also affected. The results after corrective surgery on the foot with the Ilizarov fixator and the findings during arthroscopy of the knee are discussed. The literature is reviewed.
Velocity of the middle cerebral artery was recorded with transcranial pulsed doppler in 10 neurally-mediated syncopes elicited by 60 degrees head-up tilt test. Mean arterial blood pressure decreased by -36 +/- 16 percent (P < 0.0001) and heart rate by -6 +/- 27 percent (P < 0.05). Mean middle cerebral artery velocity decreased by -48 +/- 16 percent (P < 0.0001); Pourcelot's resistance index increased by 74 +/- 47 percent (P < 0.0001) and Gosling's pulsatility index by 218 +/- 111 percent (P < 0.0001). However, resistance normalized with mean arterial pressure showed no significant increase (+ 14 +/- 28 percent; NS). The decrease in diastolic velocity as well as mean arterial blood pressure and heart rate was significantly lower when loss of consciousness occurred. Contrary to those of other authors, our results do not support the hypothesis that syncopes result from a paradoxical cerebral vasoconstriction since no significant changes were observed in resistance normalized with mean arterial pressure. Thus, decrease in cerebral perfusion is likely to be the result of a decrease in cerebral perfusion pressure.
The combination of a diffuse pigmented villonodular synovitis and a rotator cuff tear of the shoulder in a 64-year-old man is described. The patient was treated by complete synovectomy, open repair of the rotator cuff tear and a Neer acromioplasty. Six months after this surgical treatment the patient was free of pain, and clinical examination revealed an almost normal range of motion.
A survey of institutionalized adults with severe mental retardation and chronic regurgitation was conducted. A high prevalence of dysphagia and gastroesophageal abnormalities was found. Many of these abnormalities require further evaluation and treatment prior to the diagnosis of rumination. More studies are needed to explore the causes and treatment approaches for chronic regurgitation in adults with developmental disabilities.
Between 1985 and 1986, 109 consecutive patients with unexplained syncope after clinical and standard electrocardiographic examination underwent electrophysiological investigation. In 61 cases (56%), 35 men and 26 women (mean age 69 +/- 13 years) no firm diagnosis could be made. These patients were the study group. Underlying cardiac disease was present in 23%, coronary artery disease in 10% of cases. In 33 cases, the basal ECG was normal (54%). Sixty patients (one lost to follow-up) were studied over an average of 38 +/- 12 months. Global mortality and recurrence rate were 13 and 18% respectively. There were no sudden deaths in the 8 fatalities. The mechanism of the 17 recurrent syncopes was cardiac in 5 cases, vasovagal in 1 case, uncertain in 11 cases. Of the 5 cardiac syncopes, 3 were related to 3rd degree atrioventricular block occurring 7 to 49 months after the initial electrophysiological investigation. No predictive criteria of recurrence could be identified. Empiric treatment proposed to 28% of patients did not prevent recurrent syncope and did not improve global survival. Inconclusive electrophysiological investigation of patients with unexplained syncope defines a population with a low risk of sudden death. Recurrent syncope is common. The recurrence of symptoms is an indication to repeat the aetiological investigations which should include a tilt-test ot another electrophysiological investigation. Empiric treatment has not been shown to be effective.
Human papillomavirus (HPV) types 6 and/or 11 have been associated with benign lesions, while types 16, 18, 31, and 33 are prevalent in malignant lesions. This case report describes the findings in a verrucous carcinoma of the leg, which was examined for HPV types 11, 16, and 18 by in situ DNA hybridization. The lesion gave positive results for HPV subtypes 11 and 18, a combination that, to our knowledge, has not been previously reported in this neoplasm.
Complete atrioventricular block (AVB) following radiotherapy has been reported rarely, usually after high dose mediastinal irradiation for Hodgkin's disease or lung or breast carcinoma. We report six new cases of episodic complete infranodal AVB, requiring permanent pacemaker implantation. The mean age was 48-years old (ranging from 25-60) at the first Adams Stokes attack, mean delay was 12 years after irradiation (10-18), and mean radiation dose was 5,200 rads (4,000-6,500). All patients had abnormal interval electrocardiograms (right bundle branch block in two, left bundle branch block in three, alternating left and right bundle branch block in one). Electrocardiograms during the episode of AVB or Holter recordings were consistent with infranodal block in all patients; electrophysiological study performed in five patients confirmed infranodal AVB in four, and one was normal. Pericardial disease was constant, which included pericardial constriction in four patients. Two patients died after failure of pericardiectomy to improve congestive heart failure, due to epicardial, myocardial, and endocardial involvement. Noncardiac mediastinal lesions were present in four cases. Since this delayed complication may occur in patients of such age that the relation between the AVB and the chest irradiation is questionable, we propose the following etiologic criteria; high radiation dose (over 4,000 rads); delay of 10 years or more; abnormal interval tracings; pericardial involvement; and associated cardiac or mediastinal radiation-induced lesions.
In both radiological and orthopedic journals the value of MRI for diagnosing internal derangement of the knee has been assessed recently. However, results vary widely and no study reports on the differentiation among types of ACL tears. As far as meniscal pathology is concerned, attention has been drawn by Reicher et al. (11) and Glashow et al. (5) upon the false positive tears of the posterior horn of the medial meniscus. Where most authors consider signal inversion in the posterior horn of the meniscus as a normal finding in children--due to the higher water content--the same fact in adults can be interpreted as a false positive image or a missed tear at arthroscopy (5).
Explore the source record for details and available documents.
In patients with Wolff-Parkinson-White syndrome the anterograde conduction properties of the accessory pathway determine the ventricular rate in case of atrial fibrillation (AF). Anterograde conduction in the accessory pathway was evaluated in 20 patients (mean age 31 years) by means of transoesophageal atrial pacing with increasing frequency (up to 460 per minute), first at rest, then during exercise on an ergometric bicycle and upon immediate recovery. The exploration was completed by a search for the disappearance of pre-excitation during exercise and after an intravenous injection of ajmaline 1 mg/kg. The shortest cycle (SC) of atrial pacing with 1:1 conduction by the accessory pathway regularly decreased by 80 +/- 26 ms (n = 18), i.e. 27 p. 100 of its value at rest. At immediate recovery SC increased by 40 +/- 53 ms (n = 9). Atrial fibrillation was induced at rest and/or during exercise in 12 patients. The shortest interval (SI) between two pre-excited ventricular complexes was 290 +/- 80 ms (n = 8) at rest and 244 +/- 53 ms (n = 8) during exercise. With a substantial group of values (n = 12) there was good correlation between SC and SI both at rest and during exercise. With a smaller group of values (n = 3) SI was clearly greater than SC, suggesting a concealed conduction in the accessory pathway during atrial fibrillation. Disappearance of pre-excitation during exercise was observed in 4 patients, 3 of whom had a short (less than 250 ms) SC and/or SI.(ABSTRACT TRUNCATED AT 250 WORDS)
The purpose of this study was to assess the ability of isoproterenol (IPNA) to provoke chest pain, electrocardiographic (ECG) changes and transient defects on thallium 201 myocardial scintigraphy for coronary artery disease (CAD) diagnosis. Thirty patients without prior myocardial infarction who underwent coronary angiography were included. Significant stenosis was found in 15 and absent in the other 15. The most relevant clinical and ECG data were observed in the few minutes that followed IPNA perfusion: 1) angina pectoris occurred in ten patients of whom eight had CAD (sensitivity: 53 p. cent + 13 p. cent; specificity: 87 p. cent + 9 p. cent); 2) ST segment depression was observed in 11 CAD and 3 non-CAD patients (sensitivity: 73 p. cent + 11 p. cent; specificity: 30 p. cent + 10 p. cent); 3) reversible perfusion defects on planar myocardial thallium 201 scintigrams occurred in 16 patients of whom 13 had CAD. Thallium scintigraphy sensitivity was 87 p. cent + 9 p. cent and specificity was 80 p. cent + 10 p. cent. The combined interpretation and stochastic sequential analysis of two or three presumed independent criteria increased significantly the diagnostic value of the test. We conclude that the isoproterenol test is a safe and reliable method to provoke myocardial ischemia with clinical, ECG and myocardial scintigraphic expression. It has an information content nearly identical to exercise stress test for CAD detection. Because it allows a three step sequential probability analysis, the diagnosis is more reliable than with other pharmacological tests which apply only to scintigraphy.
In a series of 2286 single radiographic examinations of the knee in 1985, 6 dorsal defects of the patella (DDP) were detected. The diagnosis was made if a round lucent lesion of the dorsal superolateral surface of the patella was found abutting against articular cartilage. In four of our patients, an association with a multipartite patella (MP) was found. Biopsy of one lesion showed dense connective tissue and areas of bone necrosis. In one patient, the pattern of reossification of the lesion could be demonstrated. Our observations provide further evidence that the DDP is a stress-induced anomaly of ossification rather than a post-traumatic subarticular cyst of the patella, a diagnosis sometimes suggested by the clinical context. The initial lesion is probably a traction lesion at the insertion of the vastus lateralis muscle rather than ulceration of articular cartilage. We suggest a possible relationship between dysfunction of the quadriceps mechanism, patellar subluxation, and the genesis of the DDP.
Diagnostic reagents for detection of human immunodeficiency virus (HIV) exposure with improved reliability may be provided by viral encoded proteins produced by recombinant DNA techniques or by synthetic peptides corresponding to appropriate viral epitopes. We have expressed at high levels in E. coli a gag gene segment corresponding to approximately 97% of the p55 gag precursor protein, as well as a novel gag/env fusion protein that contains antigenic determinants in common with gag p24, env gp41, and env gp120. The gag and gag/env proteins were purified from insoluble inclusion bodies by sequential extraction with increasing concentrations of urea. These components were tested for reactivity with antisera to HIV proteins and peptides. We have also chemically synthesized a peptide corresponding to env residues 578-608, representing a portion of env gp41. The final preparation of gag and gag/env proteins in 8 M urea reacted with sheep anti-HTLV-III p24 gag antibodies and acquired immune deficiency syndrome (AIDS) patient sera. The gag/env fusion protein also reacted with rabbit anti-HIV env 500-511 peptide antibody. Both recombinant proteins and the env peptide were suitable as reagents for evaluation of serum samples by enzyme-linked immunosorbent assay (ELISA). Results of ELISA assays utilizing the recombinant viral proteins and synthetic peptide were in good agreement with results obtained using disrupted virus as antigen in ELISA assays and immunoblotting.
The efficacy of transcutaneous pacing was studied in 33 patients during general anaesthesia. The temporary pacing was effective in all cases. Stimulation thresholds ranged from 85 to 150 mA (mean : 110 +/- 17). In all 33 patients, external pacing was effective in producing a pulse without significantly reducing arterial pressure. Stimulation thresholds were only influenced by electrode position; age, weight, thoracic diameter and cardiothoracic ratio did not have any effect on them. No adverse effects of transcutaneous pacing were recorded. Transcutaneous pacing can be an alternative to transvenous right ventricular endocardiac pacing in the operating room in some circumstances.
Explore the source record for details and available documents.
The finding of a first-degree atrioventricular block suggests various mechanisms of atrioventricular (AV) node alteration: organic lesion, or functional disorder related to the autonomic nervous system, or a combination of both. The influence of the autonomic nervous system was evaluated by administration of Jose's regimen, i.e. intravenous injection of propranolol 0.2 mg/kg bodyweight and atropine 0.04 mg/kg bodyweight. This regimen was tested in 101 patients divided into two groups: 38 subjects with normal sinus node and AV node acting as controls, and 63 patients with abnormal AV node. In the control group the autonomic nervous system had no influence on atrio-hisian (AH) conduction time or on the effective refractory period of the AV node under an imposed cycle of 600 ms. Wenckebach's period significantly (p less than 0.01) increased from 352 +/- 40 ms to 376 +/- 47 ms. Parasympathetic activity was found to predominate in the sinus node. In the group with pathological AV node three types of response were observed after pharmacological inhibition of the autonomic nervous system: (a) improvement or even complete normalization (40%) of AV node conduction ability (AH, Wenckebach's period) suggesting vagal hyperactivity, as also found in the sinus node; (b) changes similar to those observed in the control group and reflecting the same behaviour of the autonomic nervous system, and (c) increase in AH conduction abnormalities reflecting the presence of a sympathetic overdrive tending to minimize the consequences of an atrioventricular organic lesion. This sympathetic overdrive was also found to be present in the sinus node.