Accidental quinidine poisoning in two children.

Two cases of acute accidental quinidine poisioning in two children are presented. Both cases are characterized by the same ECG abnormalities consisting of rhythm disorders and AV and intraventricular conduction defects. It is suggested that there is a causal relationship between the electrophysiologic cardiac effects of quinidine and the ECG abnormalities observed. Both patients were successfully treated by continuous intravenous infusion of a hypertonic sodium chloride solution and lidocaine.

A characterization of HRV's nonlinear hidden dynamics by means of Markov models.

A study of the 24-h heart rate variability's (HRV) hidden dynamic is performed hour by hour, in order to investigate the evolution of the nonlinear structure of the underlying nervous system. A hierarchy of null hypotheses of nonlinear Markov models with increasing order n is tested against the hidden dynamic of the HRV time series. The minimum accepted Markov order supplies information about the nonlinearity of the HRV's hidden dynamic and consequently of the underlying nervous system. The Markov model with minimum order is detected for each hour of the RR time series extracted from seven 24-h electrocardiogram records of patients in different pathophysiological conditions, some including ventricular tachycardia episodes. Heart rate, pNN30, and LF/HF index plots are reported to serve as a reference for the description of the patient's cardiovascular frame during each examined hour. The minimum Markov order shows to be a promising index for quantifying the average nonlinearity of the autonomic nervous system's activity.

Circadian variations of heart rate and premature beats in healthy subjects and in patients with previous myocardial infarction.

Chronobiological analysis of the circadian variations of heart rate, ventricular and atrial ectopies, was carried out on 11 patients with previous myocardial infarction matched with 11 controls. Individual circadian rhythms in heart rate were seen in all the control subjects but only in 6 patients with previous myocardial infarction. The behaviour of the individual circadian rhythms of premature beats was not significantly different between the two groups. A significant group rhythm in ectopies was not demonstrated, nevertheless a trend to higher frequency of arrhythmias during the activity span was detected. These results do not allow to postulate a circadian pattern of arrhythmias common to all the subjects examined. Therefore, the individual circadian behaviour of premature atrial and ventricular beats should be recognized for monitoring antiarrhythmic therapy. A significant group rhythm in heart rate was demonstrated for the two populations studied and linear discriminant analysis showed that the amplitude of this rhythm was significantly lower in patients than in controls. Possibly, myocardial infarction may affect the sinus node function producing a "flattened" range of heart rates during the 24 hours.

Knowledge-based and data-driven models in arrhythmia fuzzy classification.

OBJECTIVES: Fuzzy rules automatically derived from a set of training examples quite often produce better classification results than fuzzy rules translated from medical knowledge. This study aims to investigate the difference in domain representation between a knowledge-based and a data-driven fuzzy system applied to an electrocardiography classification problem. METHODS: For a three-class electrocardiographic arrhythmia classification task a set of fifteen fuzzy rules is derived from medical expertise on the basis of twelve electrocardiographic measures. A second set of fuzzy rules is automatically constructed on thirty-nine MIT-BIH database's records. The performances of the two classifiers on thirteen different records are comparable and up to a certain extent complementary. The two fuzzy models are then analyzed, by using the concept of information gain to estimate the impact of each ECG measure on each fuzzy decision process. RESULTS: Both systems rely on the beat prematurity degree and the QRS complex width and neglect the P wave existence and the ST segment features. The PR interval is not well characterized across the fuzzy medical rules while it plays an important role in the data-driven fuzzy system. The T wave area shows a higher information gain in the knowledge based decision process, and is not very much exploited by the data-driven system. CONCLUSIONS: The main difference between a human designed and a data driven ECG arrhythmia classifier is found about the PR interval and the T wave.

False aneurysm of the ascending aorta following cannulation.

The development of a false aneurysm of the ascending aorta following arteriotomy and cannulation of the aorta performed during closure of a ventricular septal defect is described. The evidence suggest that the sutures of the arteriotomy led to rupture of the aortic wall and secondarily late formation of a false aneurysm.

[Reflex syncope as a preliminary symptom of a rhinopharyngeal lymphoma. A case report]. / Sincope riflessa come sintomo d'esordio di un tumore del rinofaringe. Descrizione di un caso clinico.

The authors report a 57 year old patient affected by rhinopharyngeal NH lymphoma that appeared as a parapharyngeal space lesions-syncope syndrome. The activation of a cardioinhybitory reflex by the stimulation of the glossopharyngeal nerve seems to be the pathogenetic basis for his syndrome.

[Changes in pacemakers and the wearers of pacemakers as a result of the use of different electromagnetic energy sources]. / Alterazioni nei pacemaker e nei portatori dei pacemaker in conseguenza dell'uso di varie sorgenti di energia elettromagnetica.

Over the past decade there have been considerable advances in cardiac electrostimulation technologies. However, there are still reports of electromagnetic interference with pacemakers and pacemaker patients. We have studied the effects of various electromagnetic sources (short-wave diathermy, electrosurgical knives, electrotherapy and radiofrequencies) on both humans and animals. The results of the studies were completely negative and, therefore, we are convinced that today's pacemakers are much more reliable and hence less subject to interference from external electromagnetic sources. We performed the following tests: (a) Short-wave diathermy: various electrode positions in pigs and 8 patients with pacemakers. (b) Electrosurgical knives: several tests on pigs with unipolar electrosurgical knife; 6 tests on humans during automatic defibrillator implantation using two-pole electrosurgical knives; 23 pacemaker patients underwent abdominal surgery (3 inguinal hernias, 12 gastric resections; 6 cholecystotomies, 2 aortic aneurysms-with two-pole electrosurgical knives). (c) Electrotherapy (TENS): on pigs. (d) Radiofrequency (RF) for transcatheter ablation-several tests on pigs.

[Risk stratification in patients with a first myocardial infarct based on simple clinico-instrumental variables]. / Stratificazione del rischio in pazienti con primo infarto miocardico in base ad alcune semplici variabili clinico-strumentali.

UNLABELLED: It is an acknowledged fact that the prognosis for patients with a first myocardial infarction depends mainly on the degree of residual left ventricle function. We wanted to evaluate the importance that certain simple clinical and instrumental variables can have in stratifying post-infarction cardiovascular risk with particular emphasis on chronic obstructive lung disease (COLD). We selected 97 out of the 512 patients treated in the coronary intensive care unit (CICU) from February 1, 1988 to October 31, 1990 according to the following criteria: First myocardial infarction; no cardiogenic shock; no serious concomitant diseases with considered negative prognosis within 6 months. The following variables were considered for all the patients: age; sex; positive family history for ischemic heart disease; history of diabetes mellitus; arterial hypertension; previous cerebrovascular incident; history of obstructive arteriopathy of the lower limbs, of angor and COLD. The following tests were performed on all the patients: echocardiogram prior to discharge form the CICU; angiocardioscintigraphy with Tc-99 between the 20th and 30th day following the acute event; bicycle ergometer stress test on the 30th day. END POINTS: general mortality; cardiac mortality; non-fatal reinfarction; residual angina at 3 months. All the patients were treated with aspirin (325 mg/die) and/or heparin (12,500 units subcutaneously). All 97 patients were monitored for a mean follow-up time of 19.8 months. General mortality was 2.08% (for reinfarction) 24 (24.7%) non-fatal cardiac events.(ABSTRACT TRUNCATED AT 250 WORDS)

Primary coronary angioplasty in acute myocardial infarction: is it possible to prevent postinfarction cardiac rupture?

BACKGROUND: Cardiac rupture is a leading cause of death among patients hospitalized for acute myocardial infarction (AMI). The aim of our retrospective study was to evaluate the impact of primary coronary angioplasty (PTCA) on this not common but usually fatal complication. METHODS: Since January 1998 PTCA has been the routine treatment for AMI patients in our Institution monitored during the first 12 hours from symptom onset. The AMI patients hospitalized between January 1998 and December 1999 (Group A) were retrospectively compared to those observed between January 1996 and December 1997 (Group B, historical control group), mainly treated with systemic thrombolysis. Patients hospitalized after 12 hours of symptom onset were excluded from the study. Data were analyzed on an intention-to-treat design. RESULTS: Group A consisted of 204 patients (148 males, 56 females, mean age 67 +/- 11 years), 165 (81%) of whom underwent coronary angiography. Group B consisted of 185 patients (123 males, 62 females, mean age 71 +/- 12 years), 78 (42%) of whom were treated with thrombolysis and 33 (18%) with PTCA. The groups did not differ as regards the time delay before hospital entry, Killip class at admission and site of AMI. Fourteen patients (6.8 %) of Group A and 20 (10.8%) of Group B died in the Cardiology Division. No deaths due to cardiac rupture were observed among the 165 Group A patients, nor among the 33 Group B patients treated with PTCA. Cardiac rupture was the cause of death for 1 out of 14 (7%) patients in Group A, and for 8 out of 20 (40%) patients in Group B (p < 0.02 Group A vs Group B). Nine Group A patients and 11 Group B patients died because of cardiogenic shock. CONCLUSION: A lower cardiac rupture incidence was observed among Group A patients in comparison to those of Group B. Thus our data, although not randomized, suggest the ability of primary PTCA in preventing post-AMI cardiac rupture.

[Infective endocarditis: a complication of idiopathic hypertrophic subaortic stenosis (author's transl)]. / La endocardite infettiva nella cadiomiopatia ostruttiva.

The idiopathic hypertrophic subaortic stenosis (IHSS) is thought to be infrequently complicated by infective endocarditis. Because IHSS is a disorder of the myocardium and not endocardium is not generally considered to have increased risk of infective endocarditis. Some Authors found, however, that approximately 5% of patients with IHSS develop bacterial endocarditis, because hemodynamically IHSS is like to valvular diseases. Therefore the incidence of endocarditis in IHSS is the same of valvular diseases. The vegetations can be found on anterior mitral valve leaflet, aortic cusps and subaortic endocardium. Some patients have dental surgery prior to the onset of endocarditis and others are infected with oral streptococci. For these reasons prophylactic antibiotics should be administered to patients with IHSS undergoing dental manipulation and in other settings where the risk of developing bacteremia is high. We describe one case of IHSS complicated with streptococcus viridans endocarditis. Vegetations, determined with echocardiography, were present on anterior mitral valve leaflet, aortic right coronary cusp and interventricular septum. In a review of literature we are been able to find twenty-seven cases of IHSS complicated with endocarditis.