Linear and nonlinear parameters of heart rate variability in ischemic stroke patients.

INTRODUCTION: Cardiovascular system presents cortical modulation. Post-stroke outcome can be highly influenced by autonomic nervous system disruption. Heart rate variability (HRV) analysis is a simple non-invasive method to assess sympatho-vagal balance. OBJECTIVES: The purpose of this study was to investigate cardiac autonomic activity in ischemic stroke patients and to asses HRV nonlinear parameters beside linear ones. METHODS: We analyzed HRV parameters in 15 right and 15 left middle cerebral artery ischemic stroke patients, in rest condition and during challenge (standing and deep breathing). Data were compared with 15 age- and sex-matched healthy controls. RESULTS: There was an asymmetric response after autonomic stimulation tests depending on the cortical lateralization in ischemic stroke patients. In resting state, left hemisphere stroke patients presented enhanced parasympathetic control of the heart rate (higher values for RMSSD, pNN50 and HF in normalized units). Right hemisphere ischemic stroke patients displayed a reduced cardiac parasympathetic modulation during deep breathing test. Beside time and frequency domain, using short-term ECG monitoring, cardiac parasympathetic modulation can also be assessed by nonlinear parameter SD1, that presented strong positive correlation with time and frequency domain parameters RMSSD, pNN50, HFnu, while DFA α1 index presented negative correlation with the same indices and positive correlation with the LFnu and LF/HF ratio, indicating a positive association with the sympatho-vagal balance. CONCLUSIONS: Cardiac monitoring in clinical routine using HRV analysis in order to identify autonomic imbalance may highlight cardiac dysfunctions, thus helping preventing potential cardiovascular complications, especially in right hemisphere ischemic stroke patients with sympathetic hyperactivation.

[Prospective epidemiologic and clinical observations on the prevalence of risk factors for stroke, performed on 374 inpatients, during the period of June 2001-June 2004]. / Observatii prospective epidemiologice si clinice asupra prevalentei factorilor de risc pentru accidentul vascular cerebral, realizate pe un lot de 374 de bolnavi, în perioada iunie 2001-iunie 2004.

UNLABELLED: Within the framework of cardiovascular pathology, with an epidemopandemic aspect, the stroke, through its mortality and sequels, represents, worldwide, a major problem of community health. In this context, we present the results of an epidemiological and clinical study, both prospective and interdisciplinary, performed on a sample of 374 inpatients suffering from stroke, hospitalized in the Neurology Ist Clinic of Iasi, during the period June 2001-June 2004. The characteristics of the studied sample: age--78.8% over 51 years old, sex--53.7% male; residence--51.4% urban; provenance: rural--70.0% (p<0.001); studies: higher education--7.7% ; pensioners--76.2%; passive finding--96.8%; previous hospitalizations for cardiovascular diseases and/or diabetes mellitus: 48.2%; blood groups: OI and AII--86.61%. RESULTS: Risk factors for stroke: 56.6%--BMI > 25; "A" behavior type (Bortner's test)--63.8%; stress: familial--74.1% and occupational--25.9%; excess consumption: alcohol--11.4%; salt--32.8%; tobacco--24.9%; passive smoking--10.8%. Releasing and aggravating risk factors: arterial hypertension (AHT)--55.4% (p<0.001); obesity--12.9%; diabetes mellitus--12.5%. Hereditary antecedents: AHT--46.8%; ischemic cardiopathy and myocardial infarction--15.6%; obesity and dyslipidemia--15.0%; stroke--10.8%. CONCLUSIONS: In this study, the multifactorial and associative etiology of stroke is confirmed once more, and the estimate costs of 1.21 milliard lei, only for the 10-day average hospitalization, for each of the 374 inpatients.

[Autonomic dysfunction in acute inflammatory demyelinating polyneuropathy]. / Manifestari disautonomice în polineuropatiile demielinizante inflamatorii acute.

Acute inflammatory demyelinating polyneuropathy (AIDP) is an autoimmune process that is characterized by progressive weakness, mild sensory changes and autonomic dysfunction. It is a rare disorder, afflicting about 1 person in 100,000. Yet, since the decline in the number of polio cases, it represents the most common cause of acute neuromuscular paralysis. AIDP is thought to arise as a result of the production of antibody to bacterial Campylobacter jejuni, sugar-containing surface antigen(s) that, due to molecular mimicry, cross-react with the myelin sheath and the axons of nerve cells. Antibody and/or cell mediated immune reactions are believed to produce degeneration of the nerve or interruption of neurotransmission. Autonomic dysfunction include: transient hypertension or, less often, hypotension, sinus tachycardia, bradycardia, urinary retention who usually improves in parallel with motor and sensory function. Our purpose was to study the disturbances of autonomic function of the patients with acute idiopathic demyelinating polyneuropathy. We had studied 36 patients with AIDP admitted in I-st Clinic of Neurology, Iassy, between 1998 and 2002. Analyzing the evolution of these autonomic disturbances we observed the early onset together with motor symptoms, tachycardia and tachypnea was more persistent and a real vital risk factor.

[Absence seizure--recent physiopathologic data]. / Absentele epileptice--actualitati în fiziopatologie.

The progresses in clarifying the normal and pathologic cellular and molecular mechanisms are reflected in the elucidation of the way some of the most common forms of generalized seizure--absence seizures--occur and are produced. Intrinsic properties of the thalamic neurons that give them the ability to release or preserve oscillatory, low-frequency neuronal discharges, and the thalamo-cortical feedback mechanism seem to explain the pathogenesis of absence seizures. The involvement of GABA receptors in the regulation of membrane calcium channels, as well as their genetically-induced changes are new pieces in the pathogenic puzzle.

[Neurogenetics in Parkinson's disease]. / Neurogenetica în boala Parkinson.

The pathogenesis of Parkinson's disease, a progressive degenerative disorder of the central nervous system, remains obscure. 20% of cases are familial. The disorder may be due to a combination of genetic and environmental factors. Some monogenic forms of Parkinson's disease have been described. Many genetic studies explore whether a candidate gene may confer an increased risk for this disease. The search for a genetic susceptibility may lead to establish a preventive therapy.

[Clinical imaging correlations in lacunar infarcts]. / Corelatii clinico-imagistice în infarctele lacunare.

PURPOSE: This paper is a study concerning the clinical-imagistic correlations in lacunar infarcts causes and associated lesions in these ones. We made an attempt to find out and emphasize the risk factors, causes and pathogenic mechanisms involved in lacunar syndromes. MATERIALS AND METHODS: We studied 138 patients with lacunar infarcts diagnosed by clinical examination and computer tomography. The investigation of risk factors evidenced arterial hypertension in 75 cases (54%). The clinical features of lacunar syndromes were: 1) pure motor stroke 41c; 2) pure sensory stroke 8c; 3) ataxic hemiparesis 9c; 4) dysarthria-clumsy hand 1c; 5) sensorimotor stroke 21c; 6) Landry syndrome 1c. RESULTS: We correlated the clinical manifestations and complementary investigations what enabled us to charge in determining of lacunar infarcts: focal microangiopathy-small artery disease (75c), cardio-embolic mechanism (12c), arterio-arteriolar embolic mechanism (15c). The risk factors and pathogenic mechanisms need more adequate research in order to find appropriate prevention and medical attendance.