Periictal heart rate variability analysis suggests long-term postictal autonomic disturbance in epilepsy.

BACKGROUND: One of the possible pathomechanisms of sudden death in epilepsy (SUDEP) is a postictal dysregulation of autonomic nervous system. We performed a heart rate variability (HRV) analysis of the periictal state to analyze whether a cardiac autonomic disturbance exists after an epileptic seizure. METHODS: We included 31 periictal video-EEG-ECG recordings of 31 patients with epilepsy who had consecutively undergone pre-surgical evaluation. Nine generalized tonic-clonic (GTCS), 15 complex partial, and seven simple motor seizures were included. HRV was evaluated by analyzing 5-min-long ECG epochs, sampling from baseline, direct preictal, early-postictal (<15 min after the seizure), and late-postictal (5-6 h after the seizure) periods. RESULTS: The heart rate was elevated immediately after the seizures, but 5-6 h postictally returned to the baseline level. Time-domain components of HRV decreased after the seizure and this decrease lasted for 5-6 h. Low-frequency power decreased in the early-postictal phase and high-frequency power of HRV dropped in the late-postictal phase. GTCS had an impact on short-term but not on long-term postictal HRV decrease. CONCLUSIONS: We found decreased HRV immediately after the seizures, which lasted at least 5-6 h postictally, indicating a long-term postictal disturbance of the autonomous nervous system. GTCS were accompanied by a more decreased HRV than other seizures. Our results may have relevance in explaining pathomechanism of SUDEP.

In vivo R1-enhancement mapping of canine myocardium using ceMRI with Gd(ABE-DTTA) in an acute ischemia-reperfusion model.

PURPOSE: To demonstrate the usefulness of normalized DeltaR1 (DeltaR1(n)) mapping in myocardial tissue following the administration of the contrast agent (CA) Gd(ABE-DTTA). MATERIALS AND METHODS: Ischemia-reperfusion experiments were carried out in 11 dogs. The method exploited the relatively long tissue lifetime of Gd(ABE-DTTA), and thus no fast R1 measurement technique was needed. Myocardial perfusion was determined with colored microspheres (MP). RESULTS: With varying extent of ischemia, impaired wall motion (WM) and lower DeltaR1(n) values were detected in the ischemic sectors, as opposed to the nonischemic sectors where normal WM and higher DeltaR1(n) were observed. Based on the DeltaR1(n), data from the myocardial perfusion assay and the DeltaR1(n) maps were compared in the ischemic sectors. A correlation analysis of these two parameters demonstrated a significant correlation (R = 0.694, P < 0.005), validating the DeltaR1(n)-mapping method for the quantitation of ischemia. Similarly, pairwise correlations were found for the MP, DeltaR1(n), and wall thickening (WT) values in the same areas. Based on the correlation between DeltaR1(n) and MP, DeltaR1(n) maps calculated with a pixel-by-pixel resolution can be converted to similarly high-resolution myocardial perfusion maps. CONCLUSION: These results suggest that the extent of the severity of ischemia can be quantitatively represented by DeltaR1(n) maps obtained in the presence of our CA.

The role of free radicals in endogenous adaptation and intracellular signals.

Oxidative stress can generate a mass of oxygen free radicals (OFR) in the cells, and these OFRs can induce several acute and chronic symptoms and diseases. If the amount of the generated OFRs overwhelms the antioxidant capacity of the cells, the pathophysiological changes may lead to the death of the cell or the development of chronic degenerative diseases.The phenomenon of ischemic preconditioning has demonstrated the important role of these aggressive and harmful molecules in the endogenous adaptation mechanism of the cells to oxidative stress. After sublethal oxidative stress - mild ischemic insult - the resulting development of a few OFRs can stimulate the intracellular signal-transduction cascade of ischemic preconditioning and, through the induction of severe transcription factors, new antioxidant enzymes and heat shock proteins will be synthesized. These newly synthesized proteins will protect the cellagainst another, more serious oxidative insult in the future.

Heart rate variability analysis.

The expansion of heart rate variability analysis has been facilitated by the remarkable development of computer sciences and digital signal processing during the last thirty years. The beat-to-beat fluctuation of the heart rate originates from the momentary summing of sympathetic and parasympathetic influences on the sinus node. According to the extensive associations of the autonomic nervous system, several factors affect heart rate and its variability such as posture, respiration frequency, age, gender, physical or mental load, pain, numerous disease conditions, and different drugs. Heart rate variability can be quantitatively measured by time domain and frequency domain methods that are detailed in the paper. Non-linear methods have not spread in the clinical practice yet. Various cardiovascular and other pathologies as well as different forms of mental and physical load are associated with altered heart rate variability offering the possibility of predicting disease outcome and assessing stress.

Fatal mediastinitis after routine laparoscopic cholecystectomy.

Laparoscopic cholecystectomy is now considered a routine operation with a low complication rate. In this case study, the authors present a laparoscopic cholecystectomy patient who died of masked mediastinitis and concomitant septicemia caused by an unrecognized esophageal perforation after difficult intubation. The authors call attention to the need for early detection of perforating mediastinitis to prevent a lethal outcome from this infrequent but life-threatening condition.

[Molecular, cellular and clinical aspects of myocardial ischemia]. / A myocardialis ischaemia molekuláris, celluláris és klinikai vonatkozásai.

The authors summarize the fundamentals and actualities of the molecular and cellular background of myocardial ischaemia-reperfusion for the clinician. Metabolic changes following acute and chronic ischaemia and the role of free radicals, white blood cells, the endothelium, the heat shock proteins are reviewed. "New ischaemic syndromes" are important intrinsic adaptation mechanisms. Stunning is a transient contractile dysfunction following short periods of coronary occlusion in spite of restored perfusion. Hibernating myocardium is resulted after progressive chronic ischaemia including reversible contractile dysfunction, reduced metabolism and cellular dedifferentiation. Preconditioning means concomitant development of a protected state against lethal ischaemia after mild noxious stimuli. Several strategies are considered for myocardial cytoprotection based on the complex physiopathology of ischaemia-induced injury.

Laparoscopic gastric surgery. Early experiences.

In the Department of General Surgery the authors performed 12 elective laparoscopic gastric operations for gastric pathologies. The indications for the procedures were recurrent or therapy resistant and complicated peptic ulcer in 9 cases, benign gastric tumors in 2 cases and early gastric cancer in 1 case. Operative procedures were the next: posterior truncal vagotomy with anterior lesser curve seromyotomy (5 patients), total truncal vagotomy with gastrojejunostomy (2 patients), total truncal vagotomy with pyloroplasty (1 patient), total truncal vagotomy with antrectomy and Billroth-II reconstruction (1 patient), resection of benign gastric tumor by the transgastric approach (1 patient), Billroth-II resection for benign gastric tumor (1 patient), wedge resection of gastric wall for early gastric cancer (1 patient). Intraoperative gastroscopy was used for location of the lesion in 4 of 12 cases. Apart from delayed gastric emptying (2 cases), patients recovered without any problem. The mean hospital stay was 5.7 days. Early experiences with laparoscopic gastric surgery has shown that there are certain important advantages to the approaches. They hold the promise of less pain, less immobility, quicker alimentation, shorter hospitalization, less wound and respiratory complications and an earlier return to normal activities.

[Alternatives to heart transplantation]. / A szívátültetés alternatívái.

This paper is about the alternatives of curing the drug-refractory heart failure with the exception of cardiac transplantation. It includes even the newest methods mostly being in the phase of animal experiment in the meantime. The authors give a review on the different possibilities of skeletal muscle autotransplantation for cardiac support, such as cardiomyoplasty which has already been done in Hungary too, externally powered mechanical devices for long-term support, molecular and cellular cardiomyoplasty. The partial ventriculectomy and transmyocardial laser revascularization are mentioned as well. Although, most part of the enumerated procedures is not available in Hungary at this time, they are expected to enter the arsenal of medicine in the future.