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PubMed2005

Rhinocerebral mucormycosis: pathways of spread.

Rhinocerebral mucormycosis is an invasive, opportunistic fungal infection usually seen in immunocompromised patients, and particularly in the setting of diabetes or immune deficiency. It is assumed that the port of entry is colonization of the nasal mucosa, allowing the fungus to spread via the paranasal sinuses into the orbit. Involvement of the brain and cavernous sinus occurs by way of the orbital apex; therefore, spheno-ethmoidectomy with or without maxillectomy seems to be the definitive method to eradicate this infection. We conducted a prospective study of ten patients with rhinocerebral mucormycosis from February 2000 to April 2004. Rhinocerebral mucormycosis was clinically diagnosed in 11 patients, 10 of whom were included in our study upon histopathological confirmation. Diabetes was the most common underlying disorder seen in nine out of ten patients. In this study, the patients were assessed for predisposing factors, presenting signs and symptoms, sites of extension, the number and sites of surgical debridement, as well as the outcome. Ocular, sinonasal and facial soft tissue involvement was common. Involvement of the pterygopalatine fossa at the time of debridement was evident in all patients. No invasion through the lamina papiracea or the walls of the maxillary sinus was identified. At the time of this communication, six out of ten patients were alive. For the four who died, the causes were hypokalemia, cardiac arrythmia and refractory pneumonia. Pterygopalatine fossa is considered to be the main reservoir for rhinocerebral mucormycosis, and extension into the orbit and facial soft tissues usually follows this route. After proliferation in the nasal cavity, the mucor reaches the pterygo-palatine fossa, inferior orbital fissure and finally the retroglobal space of the orbit, resulting in ocular signs. The facial soft tissues, palate and infratemporal fossa can be infected through connecting pathways from the pterygo-palatine fossa; therefore, debridement of the pterygopalatine fossa seems to be the definitive method of managing this infection.

Adult↗

PubMed1997

Electrophysiological investigation of central, peripheral and autonomic nerve function in workers with long-term low-level exposure to carbon disulphide in the viscose industry.

OBJECTIVE: Neurotoxicity of carbon disulphide (CS2) is well known. The air concentration at the workplace at which such adverse effects can first be observed is the subject of controversial discussion. METHODS: In a cross-sectional study on CS2-exposed workers peripheral motor and sensory nerve conduction studies, somatosensory evoked potentials, thermotesting and investigation of forced respiration sinus arrythmia have been carried out. The data from 222 workers exposed to CS2 in the viscose industry were evaluated and compared with data from 191 employees from the same factory with similar physical and psychological stress factors but without detectable occupational contact to neurotoxic substances. Median exposure to CS2 was below the currently valid occupational-medical threshold limit value (MAK-value) of 10 ppm. Multiple linear or multiple logistic regression analysis was used to check for statistical differences. RESULTS: Binary evaluation (comparison of exposed persons versus controls after multiple linear regression) revealed a slightly lower value in the exposed group for the motor nerve conduction velocity (MNCV, -0.76 m/s, median 48 m/s), but a long way from pathological thresholds. No dose-response relationship could be found within the exposed group for any evaluation criteria of CS2-exposure. Somatosensory evoked potentials, thermotesting and analysis of heart rate variability yielded no indication of a neurotoxic effect of CS2. CONCLUSION: Isolated decrease of MNCV in binary evaluation is, with regard to the known mechanism of CS2-neurotoxicity and the lack of a dose-response relationship, obviously not due to toxic effects. We interpret our results as showing that an adverse effect of carbon disulphide at the exposure ranges found was not detectable in the exposed group.

Adult↗

PubMed1999

The determination of cardioventilatory coupling from heart rate and ventilatory time series.

In 35 anaesthetised human subjects, we examined the effect of cardioventilatory coupling on R-R interval and ventilatory period time series. We observed that, in the presence of coupling: (a) ventilatory period fluctuated in a quantal manner, each quantal step corresponding to a multiple (or a little less) of the heart period; (b) heart period fluctuations, associated with respiratory sinus arrythmia, were identical for consecutive ventilatory periods. The regularity of heart period variation lead to geometric patterning of raw R-R time series, R-R consecutive difference time series, the phase portrait (R-R(n) vs R-R(n+1)) and the map of R-R interval variation (DeltaR-R(n) vs DeltaR-R(n+1)). These geometric features may be useful for the determination of cardioventilatory coupling from heart rate time series.

Adult↗

PubMed2006

Voltage-sensitive ion channels and cancer.

Plasma membrane voltage-sensitive ion channels classically have been associated with a variety of inherited diseases or "channelopathies" that range in the severity of symptoms from mild to lethal. Ion channels are found throughout the body and are responsible for facilitated diffusion of ions down the electrochemical gradient across cells membranes in various tissues. Voltage-sensitive ion channels open in response to changes in the membrane potential and are primarily found in excitable cells and tissues. Potassium, calcium, and sodium channels play critical roles in the development of major diseases, such as hyperkalemia, epilepsy, congenital myotonia and several cardiac arrythmias. Recently, cancer studies have begun to define the role of voltage-sensitive ion channels in the progression of cancer to a more malignant phenotype. In cancer, the increased expression or increased kinetics of voltage-sensitive ion channels is associated with an increasing malignant potential as evinced by their role in cell proliferation, migration and survival; as such, these channels are becoming the targets of significant drug development efforts to block or reduce voltage-sensitive ion channel activity in order to prevent or combat malignant disease.

Humans↗

PubMed2004

Ventricular arrhythmias after LV remodelling: surgical ventricular restoration or ICD?

UNLABELLED: Ventricular arrhythmias cause ~50% of deaths in remodeled ventricles after myocardial infarction, and the Multicenter Automatic Defibrillator Implantation Trial (MADIT II) showed that the Implantable Cardioverter Defibrillator (ICD) saved lives in high risk coronary patients with advanced left ventricular dysfunction. We studied 382 patients with remodeled hearts by preoperative Ventricular stimulation (PVS) to evaluate surgical ventricular restoration (SVR) that excludes scar and lower ventricular volume alters the early and late arrhythmia process without ICD utilization. METHODS: Clinical and hemodynamic results before and after SVR in post-infarction patients, are compared to contrast spontaneous and/or inducible ventricular tachycardia to patients without arrhythmias. Study arrhythmia groups included: Spontaneous in 87 patients with clinical documented ventricular arrhythmias and inducible or not inducible ventricular tachycardia: Inducible in 105 patients without clinical ventricular arrhythmias but PVS inducible ventricular tachycardia; and No arrhythmias in 190 patients without spontaneous or PVS inducible ventricular tachycardia. RESULTS: Preoperative LV end systolic volume index helped define preoperative arrythmia potential: Spontaneous > 120/m(2), inducible > 100 ml/m(2), and none < 100ml/m(2). Overall operative mortality rate was 7.6% (29/382). Sudden cardiac death rate was 2.5% causing 18.7% of all deaths. Surgical management reduced inducible ventricular tachycardia, from 41% preoperatively (144/352) to 8% (26/307) at early study, and 8% (14/177) one year later. Cardiac mortality was low at 5-years and not different between groups, despite use of only one late ICD device. CONCLUSIONS: Favorable electrical success rate and low mortality always included volume reduction to interrupt functional re-entry circuits, but also added endocardiectomy, cryoablation, CABG and mitral repair when needed. Overall SVR findings show volume and shape alteration limits ventricular arrhythmias that impair prognosis, and suggests ICD devices are not needed.

Cardiac Surgical Procedures↗

PubMed2005

Incidence of pulmonary vein stenosis in patients submitted to atrial fibrillation ablation: a comparison of the Selective Segmental Ostial Ablation vs the Circumferential Pulmonary Veins Ablation.

INTRODUCTION: Pulmonary vein (PV) stenosis is an important complication of the AF ablation and could be underestimated if their assessment is not systematically done. Selective Segmental Ostial Ablation (SSOA) and Circunferential Pulmonary Veins Ablation (CPVA) have demonstrated efficacy in atrial fibrillation (AF) treatment. In this study the real incidence of PV stenosis in patients (pts) submitted to both SSOA and CPVA was compared. METHODS: Those pts with focal activity and normal left atrial size were submitted to SSOA, remaining pts were submitted to CPVA to treat refractory, symptomatic AF. Contrast enhanced magnetic resonance angiography (MRA) was routinely performed in all patients 4 months after the procedure. RESULTS: A series of 73 consecutive patients (mean age of 51 +/- 11 years; 75% male) were included. SSOA was performed in 32 patients, and the remaining 41 patients underwent to CPVA, obtaining similar efficacy rates (72% vs 76% arrythmia free probability at 12 months; log rank test p = NS). Six patients had a significant PV stenosis, all in SSOA group none in CPVA group (18.8% vs 0%; p = 0.005). All patients were asymptomatic and the stenosis was detected in routine MRA. No predictors of stenosis has been identified analysing patient procedure characteristics. CONCLUSION: PV stenosis is a potential complication of SSOA not seen in CPVA. The study confirms than MRA is useful for identifying patients with asymptomatic PV stenosis.

Atrial Fibrillation↗

PubMed1979

Coronary arteriography in acute transmural myocardial infarction.

Coronary arteriography was performed 16 +/- 3 days (range 7 to 21 days) in 106 patients with acute transmural myocardial infarction (61 posterior infarct, 45 anterior infarct). Coronary arteriography was performed without serious complications. Only 44% of patients with anterior infarct had total occlusion of the left anterior descending artery while a significant stenosis of the vessel was observed in the others -27% had a single vessel disease, 49% had two lesions and 22% had three lesions; one patient had angiographically normal coronary arteries. Among the patients with posterior infarction, 21% had one vessel disease and double or triple lesions accounted for 39% of each. Sixty per cent of patients with anterior infarction and 45% with posterior infarction had no collateral vessels. In the others patients collateral circulation had a protective effect only in anterior infarction. Age has no effect on the distribution and number of lesions nor on the development of a collateral circulation. The location and severity of the lesions were not different in patients who presented with arrythmias and those who did not.

Acute Disease↗

PubMed1992

Prognostic value of changes in R-wave amplitude during exercise testing after a first acute myocardial infarction.

To investigate the prognostic value of exercise-induced changes in R-wave amplitude and their relation to other exercise and angiographic variables, 303 consecutive patients who underwent maximal exercise testing and coronary angiography within 2 months of a first acute myocardial infarction were studied. R-wave amplitude at peak exercise increased or was unchanged in 159 patients (57.4%) and decreased in 118 (42.6%). Increased R-wave amplitude was significantly related to underlying 3-vessel disease (p = 0.0001), the extent of ST-segment depression on exercise (p = 0.0001), and the time to 1 mm ST depression (p less than 0.05). Follow-up information was available in 285 patients (86.4%) at a mean of 4 +/- 1.8 years. Death from cardiac causes occurred in 25 patients (9%); 18 (6.5%) developed recurrent myocardial infarction, and 32 (11.6%) developed angina. Variables with a predictive value for cardiac death were maximal exercise heart rate (p = 0.0005), occurrence of exercise-related supraventricular arrythmia (p = 0.02), and number of diseased vessels (p = 0.02). R-wave changes had no predictive value. No variable had a predictive value for recurrent infarction. Maximal exercise heart rate (p = 0.02) and increased R-wave amplitude (p = 0.0001) were significantly related to the occurrence of angina at follow up. Exercise-related R-wave increases were associated with the presence of angina at follow-up, but had no predictive value for cardiac death or recurrent infarction; their association with subsequent angina appears to reflect an association with more severe underlying coronary disease.

Angina Pectoris↗

PubMed1981

Myocardial involvement in idiopathic hemochromatosis. Morphologic and clinical improvement following venesection.

We describe a 31 year old male patient who presented with severe cardiomyopathy caused by primary hemochromatosis. After a stormy course, complicated by heart failure and severe ventricular arrythmias, improvement in clinical status and myocardial function occurred. Depletion of myocardial iron was documented by the technique of serial endomyocardial biopsy. Myocardial iron stores were not yet depleted when hypoferremia and iron deficiency anemia occurred. This is the first reported study of myocardial morphology in a successfully treated patient with hemochromatotic cardiomyopathy.

Adult↗

PubMed1975

Intrauterine diagnosis and control of fetal ventricular arrhythmia during labor.

A very rare case of a sustained fetal ventricular arrythmia in the form of bigeminy, trigeminy, and quadrigeminy during labor is described. The rhythm distrubance failed to respond to sedatives and narcotics but was successfuly reverted to sinus rhythm following the administration of intravenous propranolol to the mother. The significance and possible mechanism of the arrhythmia is discussed.

Adult↗

PubMed1983

The identification of specific serotonergic nuclei inhibited by cardiac vagal afferents during acute myocardial ischemia in the rat.

Cardio-cardiac autonomic reflexes mediated by the cardiac vagus during acute myocardial infarction play an important role in determining post-infarction hemodynamic function and the susceptibility of the infarcting heart to lethal arrythmias. In an earlier study we had demonstrated that serotonin-containing neurons in the brain participate in the mediation of these reflexes following left coronary artery ligation in the rat. In this study we identify brain serotonin nuclei involved. The accumulation of serotonin was measured in 19 brain nuclei from rats treated with pargyline, a monoamine oxidase inhibitor. The rats were subjected to either left coronary artery ligation or sham operation with or without bilateral cervical vagotomy or lidocaine applied topically only to the left ventricle. Serotonin accumulation was markedly reduced in the nucleus hypothalamicus posterior, nucleus raphe magnus and nuclei-raphe medianus-centralis superior in the rats subjected to coronary artery ligation as opposed to sham operation; no other brain regions were affected. The topical application of lidocaine to the left ventricle or vagotomy completely obviated the ligation-induced decrease in serotonin turnover. We conclude that there is an inhibition of serotonergic activity in the nucleus hypothalamicus posterior, nucleus raphe magnus and nuclei raphe medianus-centralis superior following left ventricular myocardial infarction in the rat. The afferent signal arises from receptors in the left ventricle and is conducted by the vagus.

Animals↗

PubMed1978

A minicomputer system for display and rate analysis in vectorcardiography.

A system has been constructed for recording vectorcardiographic signal with a FM taperecorder. Off-line AD-conversion and analysis of rates and magnitudes of partial vectors are made with a minicomputer. The reason for studying particularly initial vectorrates is that according to our hypothesis these contain valuable information for classification of certain cardiac arrythmias according to supraventricular or ventricular impulse focus. Preliminary results confirm the hypothesis. In vectorcardiography one difficulty is to give an easily comprehensible presentation of the vectorloop. In this study a method for '3-dimensional' display has been developed, using a graphic display processor and varying intensities of the beam. The system is to a high degree man-machine interactive.

Arrhythmias, Cardiac↗

PubMed1980

Exercise-induced anaphylaxis.

Sixteen patients were seen because of possibly life-threatening exercise-associated symptoms similar to anaphylactic reactions. Asthma attacks, cholinergic urticaria and angioedema, and cardiac arrythmias are recognized as exertion-related phenomena in predisposed patients but are distinct from the syndrome described here. A syndrome characterized by the exertion-related onset of cutaneous pruritus and warmth, the development of generalized urticaria, and the appearance of such additional manifestations as collapse in 12 patients, gastrointestinal tract symptoms in five patients, and upper respiratory distress in 10 patients has been designated exercise-induced anaphylaxis, because of the striking similarity of this symptom complex to the anaphylactic syndrome elicited by ingestion or injection of a foreign antigenic substance. There is a family history of atopic desease for 11 patients and cold urticaria for two others and a personal history of atopy in six. The size of the wheals, the failure to develop an attack with a warm bath or shower or a fever, and the prominence of syncope rule against the diagnosis of conventional cholinergic urticaria. There is no history or evidence of an encounter with an environmental source of antigen during the exercise period.

Adolescent↗

PubMed1992

Replantation of the radial side of the hand in the rhesus monkey: anatomical and functional aspects. A preliminary study to composite tissue allografting.

Before human hand transplantation can even be considered, an appropriate research model must be studied in a non-human primate. The first ray of the hand, augmented with a radial forearm flap, was chosen as a functional composite tissue graft. Four technically successful replantation of the radial unit have been carried out. One monkey died on the first post-operative day due to cardiac arrythmia. Normal wound healing occurred in the other three animals. In three monkeys, functional sensory and motor recovery was almost complete. The monkeys were able to pick up small particles of food with the index finger and thumb. It is suggested that this model could be used for allogeneic composite tissue transplantation in a non-human primate.

Animals↗

PubMed1985

Phase I-II evaluation of carminomycin in adults with acute leukemia.

Twenty courses of carminomycin were administered to 18 evaluable adult patients with acute leukemia (14 ANLL, 2 ALL, 2 CGL-BC). All but one received daily doses of 6-14 mg/m2 for 5 consecutive days. Two patients older than 60 yr had not prior chemotherapy and the others had refractory or relapsed disease. The median age was 60 yr. Three ANLL patients achieved complete remission for 8, 9 and 9 months respectively, with no maintenance therapy. None of these had proven clinical resistance to daunomycin and/or doxorubicin. Mucositis was dose-related and dose-limiting. Nausea and vomiting were rare. Alopecia was constant. Cardiac arrythmia was ascribed to carminomycin in two patients. One episode of cardiac failure seemed clearly drug-related and recovered with symptomatic treatment. In conclusion, encouraging antileukemic activity was observed with carminomycin in poor-risk patients. At doses up to 12 mg/m2 day X 5, extramedullary toxicity remained acceptable.

Acute Disease↗

PubMed1995

Retrospective evaluation of admission criteria for paediatric electrical injuries.

In the medical community, the practice of admitting all electrical burns for 24-48 h of observation, monitoring and laboratory evaluation is widespread. This retrospective review of paediatric electrical burns was conducted to determine which patients may safely be treated as outpatients. Retrospective analysis of all paediatric burns admitted between 1980 and 1991 identified 35 patients with electrical injuries. Patients were divided into two groups for analysis: those burned by exposure to household voltages (120-240 V; n = 26) and those exposed to high voltages, in excess of 1000 V (n = 9). The majority of household electrical injuries occurred secondary to contact with the household 120 V (21/26). Contact with an extremity accounted for the largest number of these injuries (18/26). The mouth was the second most frequent site of injury (7/26). Most of these patients (20/26) had < 1 per cent BSA burn. No patient in the household-voltage group had an arrythmia that required treatment, nor were there any identified examples of compartment syndrome or other vascular complications. Seven patients did require minimal skin grafting. No deaths occurred in either group. The patients in the household-voltage group were significantly younger. High-voltage electrical injuries occurred in an older patient population and required more aggressive care and surgical intervention. This was evident at the time of initial evaluation. Based on these data, healthy children with small partial-thickness electrical burns and no initial evidence of cardiac or neurovascular injury do not appear to need hospital admission.

Adolescent↗

PubMed1979

"Neuro-cardiovascular" surgery: innovations for the treatment and prevention of cardiovascular disease.

The concept of performing surgery on the conduction system and the nervous system of the heart with the use of peripheral nervous tissue, Purkinje fibers or biophysical means, may solve many enigmas concerning the treatment of arrythmias. More importantly, a correlation is suggested between coronary artery disease, the state of depolarization of the myocardial cells, local electrical and magnetic fields, the state of local innervation of coronary blood vessels, the activity of the specialized conducting system, and higher central nervous system centers. This suggested correlation may contribute significantly in the treatment, and eventually, in the prevention of coronary artery disease.

Arrhythmias, Cardiac↗

PubMed1987

The sudden infant death syndrome induced by "the fear paralysis reflex'?

The sudden infant death syndrome (SIDS) is the greatest single cause of death between one month and one year of age in industrial countries. Its etiology still remains a mystery despite extensive research during the past decades. The outstanding problem is to define the trigger mechanism leading to death. Most theories have dealt with bodily malfunctions, infections and toxic agents, and only minor attention has been paid to a possible psychical trigger mechanism. The hypothesis is advanced that the so-called 'fear paralysis reflex' (for other terms, see below), an atavistic reflex present in the entire animal kingdom, may be a major trigger mechanism for SIDS. The reflex is evoked by fear resulting from any threatening event which is perceived as a danger, and with which the organism is unable to cope, typically in a predator confrontation. Important threatening stimuli in animals, and which may be of particular importance in human infants, are restraint of movement, sudden and unfamiliar noises, separation from the mother and companions, and sudden exposure to an unfamiliar environment. The main response characteristics are an immediate motor 'paralysis' (prolonged and generalized immobility), unresponsiveness, and abrupt and profound bradycardia. The latter may proceed to asystole and fatal cardiac arrythmias. Any hypothesis attempting to explain the cause of SIDS must account for the unique age distribution of SIDS' victims with a peak age incidence at 2-4 months, its frequent occurrence in REM sleep, and the observation that most deaths are silent. Further, it must be consistent with previously established risk factors (genetic determination, opiate-addicted mothers and cigarette smoking). The fear paralysis hypothesis is in accordance with all these facts, and it suggests new and potentially hazardous triggering mechanisms which, one recognized, possibly can be avoided. As a central reflex, it does not leave any trace in the organism, which explains the negative postmortem findings. Suggestions for testing the hypothesis are given, and possible preventive measures are presented.

Age Factors↗