Linas Pieteris

Detection and evaluation of ventricular repolarization alternans: an approach to combined ECG, thoracic impedance, and beat-to-beat heart rate variability analysis.

BACKGROUND AND OBJECTIVE Beat-to-beat alteration in ventricles repolarization reflected by alternans of amplitude and/or shape of ECG S-T,T segment (TWA) is known as phenomena related with risk of severe arrhythmias leading to sudden cardiac death. Technical difficulties have caused limited its usage in clinical diagnostics. Possibilities to register and analyze multimodal signals reflecting heart activity inspired search for new technical solutions. First objective of this study was to test whether thoracic impedance signal and beat-to-beat heart rate reflect repolarization alternans detected as TWA. The second objective was revelation of multimodal signal features more comprehensively representing the phenomena and increasing its prognostic usefulness. MATERIALS AND METHODS ECG, and thoracic impedance signal recordings made during 24h follow-up of the patients hospitalized in acute phase of myocardial infarction were used for investigation. Signal morphology variations reflecting estimates were obtained by the principal component analysis-based method. Clinical outcomes of patients (survival and/or rehospitalization in 6 and 12 months) were compared to repolarization alternans and heart rate variability estimates. RESULTS Repolarization alternans detected as TWA was also reflected in estimates of thoracic impedance signal shape and variation in beat-to-beat heart rate. All these parameters showed correlation with clinical outcomes of patients. The strongest significant correlation showed magnitude of alternans in estimates of thoracic impedance signal shape. CONCLUSIONS The features of ECG, thoracic impedance signal and beat-to-beat variability of heart rate, give comprehensive estimates of repolarization alternans, which correlate, with clinical outcomes of the patients and we recommend using them to improve diagnostic reliability.

Full neurologic recovery following prolonged in-hospital cardiac arrest with resuscitation

We present an in-hospital cardiac arrest without prior hypothermia in which the patient made a complete neurologic recovery after 90 min of resuscitation. A 67-year-old woman presented herself to the emergency department with high risk unstable angina pectoris from where she was taken directly to the intensive care unit (ICU) due to changes in electrocardiography. Coronary angiography (CA) showed an occlusion of 99% of coronary bifurcation and additional stenoses of segments S6 (99%), S7 (50%), S9 (65%), S11 (99%) and S12 (90%) — a diagnosis which requires surgical intervention of coronary artery bypass grafting. Before and in the beginning of the CA procedure, the patient was in sinus tachycardia (110 bpm), which was a negative prognostic factor. 15 min after the beginning of CA, blood pressure started to fall, 5 min later — heart rate, and within the next 10 min cardiogenic shock with electromechanical dissociation had evolved. The patient was intubated and resuscitation according to the algorithm of asystole was started. Mean chest press rate was 130 times per minute. As a life-saving and time-sparing tactic, stenting of the bifurcation was chosen instead of bringing the patient to the cardio surgery unit. Stenting was conducted by making regular chest presses at the same time. Heart rhythm (HR) was returning sporadically only under the action of epinephrine, although disappearing as well. In general, there had been 20 ampoules of epinephrine (0.1%) administered. Additionally 10 mg of morphine solution had been administered intravenously. These resuscitative attempts (chest presses and injections of epinephrine) were continued for 90 min until the stents of segments S5, S6 and S11 were placed successfully and normal HR was restored. An intra-aortic balloon pump was placed with the function 1:1 for better maintenance of haemodynamic stability. After the return to the ICU, a clinical diagnosis of an anterior myocardial infarction without Q wave was established. Meanwhile, the patient was unconscious but reacted to the lavage with the pipe. A few hours later, she reacted to instructions and in the evening of the same day was successfully weaned from intubation. At the end of the first day, the administration of epinephrine was discontinued and infusions of nitroglycerin were started. Nine days later, a repeat stenting was performed (for S7, S12). During the in-hospital stay, a recurrent atrial fibrillation was registered, which was initially treated with electro impulse therapy and later on with amiodarone. The neurologist’s consultation was not performed due to the patient’s full neurologic recovery to the initial pre-arrest state. On the 25th day after hospital admission, the patient was discharged without any signs of neurological deficit. Figures 1–3 illustrate resuscitative attempts.

Diagnosis, Medical Treatment and Liver Transplantation Aspects in Portopulmonary Hypertension

Sio straipsnio tikslas - apžvelgti portopulmoninės hipertenzijos patogenezės, klinikinių israiskų, diagnostikos ir gydymo aspektus. Tobulėjant bei pleciantis transplantologijos mokslui, portopulmoninė hipertenzija tampa vis aktualesne problema. Maždaug 5-8% kepenų transplantacijai ruosiamų pacientų pasireiskia si patologinė būklė. Nustatyta, kad portopulmoninė hipertenzija ženkliai didina komplikacijų, susijusių su kepenų transplantacija, riziką bei blogina pacientų prognoze. Tik nuodugnus pacientų istyrimas ir kompleksinis plaucių kraujotakos hemodinaminių parametrų bei desiniojo skilvelio funkcijos įvertinimas leidžia parinkti optimalią gydymo taktiką. Siuo metu portopulmoninės hipertenzijos patogeneziniai mechanizmai nėra iki galo isaiskinti, bet nustatyta, kad jos issivystymui turi reiksmės plaucių kraujagyslių endotelio pažaida, vazokonstrikcinių mediatorių dominavimas, kraujagyslių remodeliacija ir trombozė. Kol kas portopulmoninės hipertenzijos gydymo standardai yra „pasiskolinti“ is kitų etiologijų plautinių hipertenzijų gydymo algoritmų, kadangi dar nėra užtektinai perspektyvinių atsitiktinių imcių tyrimų bei visuotinai priimtų rekomendacijų. Svarbiausią grandies vietą siuolaikiniame plautinės hipertenzijos gydyme sudaro vazodiliatacinės medžiagos. Ankstyvas ir tinkamas medikamentinis gydymas daugeliui pacientų gali palengvinti simptomus, pagerinti bendrą būkle ir netgi įgalinti sėkmingai atlikti kepenų persodinimo operaciją. doi:10.5200/sm-hs.2012.109

Overdose of Antiarrhytmic Drugs: Efective Medical Assistance

Overdose with antiarrhytmic drugs is very dangerous. Supportive measures are often required during the treatment of intoxication. Antiarrhythmics are known to have significant side effects and these especially include profound hypotension, vasodilation, negative inotropic effects, bradycardia. Although different classification schemes have been proposed, the first scheme (Vaughan-Williams) is still the one that most physicians use when speaking of antiarrhytmic drugs. Management of intoxication with antiarrhytmic agents includes gut decontamination with provision of respiratory support and treatment of cardiovascular system as needed. Hypertonic sodium bicarbonate, by antagonising the inhibitory effect on sodium conductance, may reverse many or all manifestations of cardiovascular toxicity. Glucagon, insulin infusion should be considered in patiens with moderate to severe calcium channel blocker and betaadrenoblocers overdose. Supportive care including the use of phosphodiesterase inhibitors, adrenergic agents, cardiac pacing, balloon pump or extracorporeal circulation is frequently indicated if antidotal therapy is not effective. Intravenous fat emulsion decreases cardiotoxity from several lipid-soluble drugs, including verapamil. Calcium salts may be given to overcome negative inotropic effects, impaired atrioventricular (AV) conduction. Hemodialysis sometimes is useful in case of sotalol overdose. Article in Lithuanian doi:10.5200/sm-hs.2012.115

New Sepsis Biomarker – Presepsin. Its Benefits and Future

Ankstyva sepsio diagnozė yra kritiskai svarbi sėkmingam sepsio gydymui. Ne mažiau svarbu nustatyti sepsio prognoze bei sekti gydymo efektyvumą. Pastaraisiais metais pastebėtas sepsio atvejų augimas, todėl svarbu surasti patikimą ir greitai nustatomą žymenį sepsio diagnostikai ir prognozei vertinti. Sioje apžvalgoje siekta aptarti naująjį sepsio žymenį – presepsiną ir palyginti jį su kitais populiariaisiais diagnostiniais sepsio rodikliais (prokalcitoninu, C-reaktyviu baltymu ir interleukinu 6) pagal specifiskumą, jautrumą ir prognozine verte. Isvados – tyrimų apžvalga parodė, kad didžiausią diagnostine ir prognozine verte pacientų isgyvenamumui turi presepsinas, lyginant su kitais žymenimis, siuo metu naudojamais sepsio diagnostikoje. Norint įsitikinti akivaizdžiu presepsino pranasumu, reikėtų atlikti daugiau klinikinių tyrimų, taciau jau dabar galime teigti, kad sis žymuo klinikinėje praktikoje yra pakankamai patikimas prognozinis sepsio rodiklis. doi:10.5200/sm-hs.2012.072