Magnetocardiography and 32-lead potential mapping: repolarization in normal subjects during pharmacologically induced stress

Signals from 37 magnetocardiographic sensors and simultaneously recorded 32 ECG leads were obtained in three healthy male subjects (including two reinvestigations). After recordings at rest, the heart rate was increased by pharmacologic stress (117 to 142 beats/min). Comparison of the repolarization of rest and stress showed substantial changes in the magnetocardiogram (MCG) up to T wave inversions during stress. In the ECG only junctional ST-T segment shifts were present. For quantification, correlation coefficients between pairs of rest and stress MCG and rest and stress ECG distributions were calculated for the same time instant at the beginning of T wave under rest and stress conditions. In addition, equivalent electrical current dipole moment and magnetic dipole moment vectors were calculated from the MCG, and their change from rest to stress evaluated. Correlation coefficients for MCG comparison ranged from 0.3 to 0.5; ECG comparison suggested much less change from stress, ranging from 0.7 to 1.0. Current dipole moment changes at T wave onset were marginal; in contrast, the magnetic dipole moment changed substantially. Since the magnetic dipole reflects vortex currents, changes in its intensity and/or orientation during repolarization suggest this as the biophysical basis of the striking difference in the response of the MCG and ECG to pharmacologic stress. Normal ECG findings at rest and under stress in healthy subjects support the conclusion that the repolarization changes in the MCG were of nonpathologic origin.

Diagnosis of small non-cleaved cell lymphoma by fine needle aspiration utilizing cytomorphologic features combined with cytogenetic analysis

OBJECTIVE

To determine the utility of cytogenetic studies in the diagnosis of small non-cleaved cell lymphoma by fine needle aspiration.

STUDY DESIGN

Cases of suspected lymphoma were identified in a prospective fashion by an immediate examination of the fine needle aspirate material by the pathologist. In these instances, additional material was aspirated directly into RPMI 1640 medium for cytogenetic studies.

RESULTS

Four cases of suspected small non-cleaved cell lymphoma were identified on fine needle aspirate material, and the diagnosis was confirmed in all cases by the presence of the characteristic (8;14) translocation or associated variant translocation in cytogenetic studies from the aspirated material.

CONCLUSION

Cytogenetic analysis is useful as an additional ancillary technique applicable to fine needle aspiration material. In the case of suspected small non-cleaved cell lymphoma, the finding of a translocation (8;14) or associated variant translocation, along with the characteristic cytomorphology, allows a definitive diagnosis by fine needle aspiration and may alleviate the need for biopsy.

Morphometric techniques in the evaluation of pulmonary vascular changes due to congenital heart disease

Open lung biopsy is performed in patients with congenital heart disease to determine the suitability for surgical correction. Controversy exists as to whether arterial density can be graded with certainty. We studied the influence on the grading (Heath-Edwards) of two morphometric techniques. Lung tissue from 14 controls and biopsy specimens from 80 patients with atrial septal defect (n=10) ventricular septal defect (n=27), complete atrioventricular canal (n=27), miscellaneous lesions (n=8) and tetralogy of Fallot (n=8) were analyzed with a planimetric method. Additionally, wall thickness was determined in 52 patients by distance measurements. The ratio of alveoli/arteries per area of lung tissue was measured. Medial thickness was "increased" on distance measurements in 15% of the cases where planimetric data showed normal wall thickness. The ratio of alveoli/arteries varied up to 43% from the mean. Hemodynamic data obtained at a median (range) time of 2 months (1 day to 18 months) before the operation did not correlate with morphologic findings. In 27 patients hemodynamic data were recorded at a median time of 1 year (3 days to 44 months) after the operation. Intimal fibrosis occupying more than 10% of the vessel lumen was associated with persistent high pulmonary vascular resistance. We conclude that morphometric techniques are useful to determine the degree of fibrosis in advanced vascular lesions. Arterial density cannot be determined in biopsy specimens with adequate certainty.

Combined superwarfarin and ethylene glycol ingestion. A unique case report with misleading clinical history

A markedly elevated prothrombin time (PT) and activated partial thromboplastin time (APTT) were observed in a 24-year-old man who was admitted with a history of ethylene glycol ingestion. Further laboratory evaluation suggested that the coagulopathy was related to acquired factor deficiencies. The PT and APTT improved transiently on usual doses of vitamin K, but rapidly became abnormal again. The coagulopathy was controlled only after large doses of vitamin K for at least 37 days. On further questioning, the patient admitted to consuming a large quantity of a rodenticide. The second generation anticoagulant rodenticides (superwarfarins) result in a potent and prolonged anticoagulant effect by reducing the activity of the vitamin K dependent factors (II, XII, IX, and X). To our knowledge, this is the first reported concomitant ingestion of both ethylene glycol and a superwarfarin compound. This case serves to illustrate how a logical laboratory evaluation can lead to the proper diagnosis, despite a misleading clinical history.

Plasma endothelin-1 in patients with left-to-right shunt

Endothelin-1 (ET-1) has been implicated in the pathogenesis of pulmonary vascular disease in patients with congenital heart disease. We studied the effect of pulmonary blood flow on plasma ET-1 concentrations. Systemic venous, pulmonary arterial, and pulmonary venous blood samples were obtained from 40 patients with atrial septal defect II (n = 21), ventricular septal defect (n = 10), persistent ductus arteriosus (n = 6), and complete (n = 2) and partial (n = 1) atrioventricular canal at cardiac catheterization and analyzed by radioimmunoassay. Median age (range) was 5.2 years (8 months to 66 years), and the resistance ratio (Rp/Rs) was 0.08 (0.03 to 0.67). Pulmonary vein to pulmonary artery ET-1 ratio in patients with "high flow" (n = 26, Qp/Qs > or = 1.5; ET-1 ratio = 0.8) did not differ from those with "low flow" (n = 14, Qp/Qs < 1.5; ET-1 ratio = 1.0). We conclude that an increase in pulmonary blood flow alone does not result in an increase in plasma ET-1.

[Incidence and characterization of large-cell anaplastic lymphoma]

PURPOSE

Large cell anaplastic lymphoma (LCAL) is a new entity among large cell lymphoma. Diagnosis is based upon morphology and on positivity to Ki1 antigen. The objectives of this study were: 1) to determine the incidence of LCAL in the patient population seen at the Instituto Roffo between 1981 and 1993; 2) to study the immunological phenotype; 3) to study the association with Epstein-Barr virus and HIV; 4) To study the expression of oncogen bcl-2 and 5) to evaluate tumoral growth factor.

MATERIAL AND METHODS

The study was done on 1030 biopsies of nodal and extranodal lymphoproliferative diseases, with Hodgkin and non-Hodgkin lymphoma. Of the 1030 consecutive cases, 67 were selected. They revealed pleomorphic cells with sinusoidal disposition. Biotin and avidin peroxidase techniques were used to identify the following antigens: CD30(Ki 1), CD45RO (UCHL1), CD20(L26), CD45(CL), Epstein Barr virus (VEB), human immunodeficiency virus (HIV), CD15, CD68, PCNA, bcl-2 oncogen, vimentin, membrane epithelial antigen (EMA). Of these cases, only 10 revealed strong positive reaction to CD 30 (Ki1), thus they were considered to fulfill criteria to be classified as LCAL.

RESULTS

1. Incidence of LCAL in the lymphoma population under study was 1%. 2. Phenotype was B in 3 cases, T in 3, and macrophage in 1.3. There was 1 case of positive EBV and 3 positive HIV. 4. Eight of 10 LCAL cases were positive for bcl-2 protein. 5. Tumoral growth factor was 57%. Also, it was noted that most cases were secondary to Hodgkin lymphoma, and a few secondary to polymorphic immunoblastic lymphoma, with negative reaction to CD15 and EMA and positive for Vimentin.

CONCLUSIONS

1. Incidence of LCAL amongst patients with lymphoma is very low. 2. Immunological phenotype is varied. 3. There was no significant association with EBV or HIV. 4. Oncogen bcl-2 was demonstrated in most cases. 5. There was a high percentage of cells in proliferation.

Malignant histiocytosis: a reassessment of cases formerly classified as histiocytic neoplasms and review of the literature

Malignant histiocytosis (MH) and true histiocytic lymphoma (THL) are hematopoietic malignancies of the mononuclear phagocytic system distinguished from each other by clinical presentation and presumed cell of origin. THL present as a localized mass derived from the fixed tissue histiocyte which may or may not disseminate. MH originates from the circulating monocyte or tissue macrophage and is characterized by a syndrome of systemic symptoms, pancytopenia, adenopathy, hepatosplenomegaly, and wasting. The distinction between MH and THL is at times arbitrary and overlap exists between these syndromes. The clinicopathologic studies that defined these entities were performed prior to the development of immunophenotyping and other molecular techniques currently used to ensure proper classification of hematopoietic malignancies. Nine patients from the University of Minnesota originally diagnosed with MH were retrospectively analyzed using a panel of antibodies reactive against T cell, B cell, and myelomonocytic antigens. Only one patient was reclassified as a possible histiocytic malignancy after reevaluation. Similar immunophenotyping studies have also shown cases previously diagnosed as MH or THL express lymphoid antigens, and would now be classified as Ki-1 positive anaplastic large cell lymphoma (ALCL) or some other hematopoietic neoplasm. These results indicate true histiocytic neoplasms are extremely rare, and previous concepts concerning clinical presentation and therapeutic outcome of the entities are inaccurate. In this paper we summarize the results of multiple retrospective analyses of cases previously diagnosed as MH or THL, including our experience at University of Minnesota, to illustrate the overall rarity of these entities. The current literature on malignant histiocytic disorders is reviewed, and the clinical presentation of patients determined to have histiocytic malignancies using contemporary analytical techniques is discussed.

Multiple plasmacytomas in skin. Harbinger of aggressive B-immunocytic malignancy

A 55-year-old alcoholic man with chronic atypical mycobacterial lung disease developed multiple plasmacytomas in the skin over a 6-month period. There was no evidence of either multiple myeloma or plasma cell leukemia at the time of diagnosis; however, evidence of multiple myeloma became apparent about 7 months later, and the man died, despite therapy for this condition, about 22 months after the initial diagnosis of his plasma cell disorder. Despite the apparent rarity of this clinical presentation, the available evidence suggests it is a harbinger of a relatively aggressive B-immunocytic malignancy.

Long-term variability of heart rate increases with successful closure of patent ductus arteriosus in preterm infants

Long-term variability (LTV) of heart rate was calculated continuously by a microprocessor in 25 preterm infants undergoing indomethacin treatment for closure of patent ductus arteriosus (PDA), in 24 preterm infants without signs of PDA, and in 10 neonates treated with prostaglandin E1 for cyanotic heart malformation. In infants with patent ductus arteriosus, LTV was lower than in controls. Following indomethacin, LTV increased most markedly (from 1.5 to 3.2; p less than 0.01) in infants with improved ventilation. The increase was less marked (from 1.8 to 2.5; p less than 0.05) in infants whose degree of respiratory failure did not change. LTV remained largely unchanged in infants who deteriorated. In 9 out of the 10 neonates treated with prostaglandin E1, LTV increased. We conclude that LTV corresponds to brain stem oxygenation and may be a useful tool to monitor treatment of PDA.

[Long-term study of anthracycline-induced cardiomyopathy in children and adolescents]

In order to detect changes in cardiac function, electrocardiographic, echocardiographic and radiologic studies were performed in 71 patients (age 1-26 yrs) who had been treated at the University Children's Hospital Berlin because of malignant diseases according to protocols of the DAL/GPO and had received anthracyclines (doxorubicin or daunorubicin) at cumulative doses up to 480 mg/m2 (median 280 mg/m2). Clinically overt cardiomyopathy was observed in one girl and required transient administration of digoxin. In 2 patients echocardiographic changes led to a reduction of the scheduled anthracycline doses. No patient died from congestive heart failure. During treatment, an increase in the cardiothoracic index was observed in 14 children, and in 16 the ECG showed pathological findings. A decrease in contractility to 25% or less as detected by ultrasound was seen in 15 patients. More than 50% of patients developed echocardiographical signs indicating an impairment of myocardial function. However, persistent changes were only found in 1 patient after discontinuation of treatment. Long-term echocardiographic follow-up studies for 4-48 months (median 14 months) after completion of anthracycline therapy were performed in 18 patients and the findings compared to matched-pair controls. The observed M-mode parameters were completely normal, and the ejection fractions calculated from the two-dimensional ultrasound investigations were in the normal range but slightly diminished compared to controls. Cardiac ultrasound is a non-invasive, reproducible and tolerable procedure for early detection of an anthracycline cardiomyopathy. In our patients, time of occurrence and the extent of pathological changes were not associated with the cumulative applied anthracycline doses.(ABSTRACT TRUNCATED AT 250 WORDS)

Catheter technique for ablation of accessory atrioventricular pathway: long-term results

Catheter ablation of an accessory atrioventricular pathway was attempted in six patients with recurrent tachyarrhythmias resistant to medication (four to five trials). Localization of the accessory pathway was performed by potential recordings with an electrode catheter from the region of the tricuspid and mitral valve rings during orthodromic supraventricular tachycardia (n = 4), during sinus rhythm (n = 1), and during ventricular pacing (n = 1). Using this mapping technique, the site of earliest atrial or ventricular activation through the accessory pathway was localized in the anterior septal (n = 2), right free wall (n = 2), posterior septal (n = 2), or left free wall (n = 1) region of the atrioventricular valve rings. The shortest ventriculo-atrial (VA) and atrio-ventricular (AV) intervals measured in the local electrograms ranged from VA = 45-70 ms, and AV = 45-65 ms, respectively. The accessory pathway responsible for the arrhythmia demonstrated exclusive retrograde (n = 4) or bidirectional (n = 2) conduction properties. A total of 13 direct-current transcatheter shocks (one to three per patient) of 20-200 J each were aimed at the site of the accessory pathway. Thereby, conduction through the accessory pathway was abolished (n = 5) or modified (n = 1) and the patients were freed from their syncope and disabling arrhythmias (follow-up: 4.6-5.9 years). The procedure was well tolerated without complications. Mapping-guided catheter ablation of accessory pathways is an effective treatment of refractory supraventricular tachyarrhythmias in selected patients.

Percutaneous intracardiac direct-current shocks in dogs: arrhythmogenic potential and pathological changes

In 12 dogs, a total of 65 direct-current (DC) shocks of 100-300 J were delivered through a standard USCI6F tripolar electrode catheter to selected sites in the heart. Severe arrhythmias were more frequent after electric shocks of high energy to the ventricles and AV-nodal or His-bundle region than after comparable shocks to the left or right atria. There was a direct relationship between the strength of the electric shocks, and the extent and severity of the injury. Application of 300 J shocks led to massive necrosis and damage to all components of the myocardium including the walls of small blood vessels. However, perforation of the atrial and ventricular walls or septum did not occur in any of the animals (mean follow-up period 97 days: range 8 to 167 days). Percutaneous DC shocks up to 250 J proved to be a safe technique for closed-chest ablation of conduction tissue in dogs. These might be of value for patients with arrhythmias requiring electrical ablation of accessory pathways or foci situated in various sites in the heart.

Pacemaker-mediated tachycardias: a new modality of treatment

Three patients with pacemaker interactive drug resistant tachycardia underwent invasive electrophysiological studies. In the first patient, the retrograde conduction of the artificial reciprocating tachycardia was provided by two right-sided accessory pathways and the antegrade conduction by an atrial synchronous pulse generator. In addition, AV-nodal tachycardia occurred alternately. In the second patient with intermittent atrial flutter, the AV node and, coincidentally, an AV sequential pulse generator provided high-rate antegrade conduction to the ventricles. In the third patient with surgical complete heart block, intermittent AV-nodal tachycardia induced retrograde atrial activation while an atrial synchronous pacemaker provided the antegrade conduction. Electrode catheter exploration of the heart allowed localization and closed-chest ablation of the accessory pathways or AV node by delivering two to seven 200-joule direct-current shocks through the appropriate electrode of the exploring catheter. Thereby, pacemaker-mediated arrhythmias could be controlled in these patients in the follow-up of 6 to 8 months.

The preoperative and postoperative findings in 627 patients with tetralogy of Fallot

The preoperative and postoperative findings in 627 patients operated for correction of tetralogy of Fallot (TOF) in the period 1960 to 1984 were analyzed in order to evaluate the clinical and hemodynamic late results. The average age was 7.2 years (range 9 months to 30 years). The patients were divided into 4 groups in order to determine the long-term prognosis in relation to the severity of the underlying anatomy; group I = without outflow tract patch; group II = with a patch up to the valve base; group III = with a transannular patch (TAP); group IV = TAP or valved conduit in patients with pulmonary atresia. Preceding shunt operations had been performed in 350 patients (55.8%); a primary correction was carried out in 277 cases (44.1%). Hospital mortality for all patients operated from 1960 to 1984 was 14.0%, late mortality, by contrast, was only 1.1%. In the last 4 years (1980 to 1983), the overall mortality considerably decreased to 3.4% (n = 29) for patients without TAP and to 8.0% for all operated patients including those with pulmonary atresia (n = 50). A comparison of the actuarial survival curves, moreover, demonstrates that the prognostic survival rate is unequivocally dependent on the severity of the anatomy of a TOF. The hemodynamic results obtained from 271 recatheterized patients from all 4 groups were designated excellent in 106 patients (39.1%), good in 100 (39.9%) and poor in 65 (23.9%). Proximal residual gradients across the right ventricular outflow tract (RVOT) were found in 30.2% of the corrected patients, and distal gradients in 24.3%. Fifty-two patients out of the 627 (8.2%) had to be reoperated for residual VSD, RVOT aneurysm, valvular pulmonary stenosis or peripheral stenosis. Intracardial electrophysiological tests carried out in 166 patients postoperatively showed an antegrade effective refractory period of the AV-node lasting over 400 ms in 47 patients (28.3%), as well as additional ventricular action potentials in 117 patients (70.4%), which could be correlated to extrasystoles or ventricular tachycardia in 37.9% of the cases. Additional AV-pathways were disclosed in 3 patients.(ABSTRACT TRUNCATED AT 400 WORDS)

Sodium and chloride transport in the isolated human cornea

22Na and 36Cl fluxes in isolated human cornea preparations were measured under short-circuited conditions. At pH 7.3-PH 7.6 sodium net flux was directed from aqueous humour to tear side, chloride net flux was statistically not different from zero. Alkalinization of the bathing solution to pH 8.6 stimulated unidirectional sodium and chloride fluxes from aqueous humour to tear side resulting in net sodium and chloride fluxes towards the tear side which both were statistically different from zero. Cyclic AMP (10(-3) M) was found to stimulate sodium and chloride unidirectional fluxes from aqueous humour to tear side, thus leading to significant net sodium and chloride fluxes in the same direction. Epinephrine (10(-4) M) increased the unidirectional chloride flux from aqueous humour to tear side more pronounced than in the opposite direction, producing a significant net chloride flux towards the tear side. The results are consistent with the hypothesis that the electrolyte pumps may under certain conditions contribute to the dehydration of the stroma.