Dynamic bubble trap can replace an arterial filter during cardiopulmonary bypass surgery

OBJECTIVE: The arterial filter (AF) and the dynamic bubble trap (DBT) reduce the number of air microbubbles passing through these devices. The aim of the study was to confirm that the DBT diminishes microbubbles in the arterial line similar to, or better than, the AF, and can replace it. METHODS: In a clinical study, we evaluated 60 patients undergoing cardiopulmonary bypass surgery, divided into two groups (30 patients each). In the first group, we used an open extracorporeal system, and in the second group, a closed system. For 15 patients in each group, the AF was incorporated, the other 15 patients received the DBT. The microbubbles were counted before and after the AF or DBT, using two-channel-ultrasonic Doppler devices. RESULTS: The exposure of patients to small bubbles (< 45 microm) is significantly higher in the AF than in the DBT group. The DBT reduces large bubbles (> 45 microm) better than the AF, with a rate exceeding 16%. CONCLUSION: The use of the DBT instead of the AF yields higher air microbubble removal efficacy, allowing replacement of the AF, assuming the AF is used for air removal purpose only.     

Eleven-years long follow-up in a patient after myocardial infarction, with low ejection fraction and recurrent ventricular tachycardia. The role of implantable cardioverter defibrillator and selective ablation

The selective ablation of the recurrent ventricular tachycardia (VT) in a 75-year old patient after extensive inferior myocardial infarction (24 years ago), with low ejection fraction was performed. In 1995 the cardioverter-defibrillator was implanted due to recurrent, symptomatic VT. The coronary angiography in 1995 and in 2006 revealed the occlusion of the right coronary and the circumflex arteries. One year after implantation, he had electrical storm caused by proarrhythmic effect of amiodarone with prolongation of QT/QTc interval. During follow up episodes of VT (approximately 5/year) were successfully terminated by ATP and rarely by cardioversion. Recently, the patient was admitted to the hospital because of the very frequent (25/day) episodes of slow (500-560 ms), sustained ventricular tachycardia. The pharmacological treatment was unsuccessful. CARTO mapping and entrainment pacing revealed VT circuit around mitral annulus. A few applications at the paraseptal part of the mitral isthmus terminated VT, which was no longer inducible. During following days there were no VTs requiring ICD interventions.     

Ventricular fibrillation in a patient with three accessory pathways, Ebstein anomaly and intermittent long QT interval. RF ablation and electrophysiologic considerations

We present a case of a 19-year old man with minor Ebstein's anomaly, intermittent long QT interval and WPW syndrome in whom atrial fibrillation, degenerating into ventricular fibrillation was the first symptom. QRS complex morphologies during atrial fibrillation revealed the presence of three accessory pathways (septal, right inferior paraseptal and antero-inferior). Immediately after resuscitation the patient was treated with amiodarone, which resulted in a significant prolongation of QT interval to 700 ms. After RF ablation of accessory pathways patient remains asymptomatic during 6-month follow up, however QTc interval is about 500 ms.     

The influence of antibiotic use on the occurrence of vancomycin-resistant enterococci

BACKGROUND: Several studies have documented the influence of antibiotic selective pressure, mainly from the use of glycopeptides, third-generation cephalosporins, quinolones and lincosamides, on the frequency of vancomycin-resistant enterococci (VRE) occurrence in hospitals. The aim of this study was to evaluate the relationship between VRE occurrence and antibiotic use in the Department of Hemato-Oncology of the Teaching Hospital in Olomouc (DHO), Czech Republic, over a 6-year period under standard and unchanged hygienic and epidemiological conditions. METHODS: During the period of 1998-2003, Enterococcus sp. strains and VRE were isolated by standard methods from clinical samples taken from DHO in-patients. The frequency of VRE occurrence was expressed as the number of isolated strains per 100 bed-days/year. DHO antibiotic consumption data were processed according to the anatomical therapeutic chemical (ATC)/defined daily dose (DDD) system valid in 2003 and expressed in defined daily dose per 100 bed-days (DDD/100 bed-days) for each year of the period. RESULTS: Since 1998, the occurrence of VRE decreased significantly (from 0.28 to 0.17 VRE/100 bed-days in 2001). Between 2001 and 2003, a significant (P < 0.05) increase from 0.17 to 0.38 was observed. The antibiotic use decreased from 205.2 in 1998 to 161.0 DDD/100 bed-days in 1999 and after an increase in 2001 (to 181.8 DDD/100 bed-days) it remained relatively stable. A significant decrease was observed in third-generation cephalosporins and quinolones (from 29.5 to 9.7 and from 42.2 to 30.2 DDD/100 bed-days respectively) between 1998 and 1999. In 2002-2003, the use of third-generation cephalosporins and glycopeptides increased substantially (from 10.1 to 13.9 and from 11.3 to 15.2 DDD/100 bed-days respectively). The Pearson correlation value was significantly positive (P < 0.05) for VRE occurrence and the use of glycopeptides and third-generation cephalosporins. CONCLUSIONS: While our study confirms the effect of use of glycopeptides and third-generation cephalosporins on occurrence of VRE, no influence of quinolones and lincosamides over the 6-year period was shown.     

The telomere-telomerase axis and the heart

The preservation of myocyte number and cardiac mass throughout life is dependent on the balance between cell death and cell division. Rapidly emerging evidence indicates that new myocytes can be formed through the activation and differentiation of resident cardiac progenitor cells. The critical issue is the identification of mechanisms that define the aging of cardiac progenitor cells and, ultimately, their inability to replace dying myocytes. The most reliable marker of cellular senescence is the modification of the telomere-telomerase axis, together with the expression of the cell cycle inhibitors p16INK4a and p53. Cellular senescence is characterized by biochemical events that occur within the cell. In this regard, one of the most relevant processes is represented by repeated oxidative stress that may evolve into the activation of the cell death program or result in the development of a senescent phenotype. Thus, the modulation of telomerase activity and the control of telomeric length, together with the attenuation of the formation of reactive oxygen species, may represent important therapeutic tools in regenerative medicine and in prevention of aging and diabetic cardiomyopathies.     

Effect of carvedilol on portal hypertension depends on the degree of endothelial activation and inflammatory changes

OBJECTIVE: Bleeding from esophageal varices is a major complication of liver cirrhosis. Non-selective beta-blockers exert an influence on the functional part of portal hypertension, thereby reducing the risk of bleeding. Direct measurement of this functional part is not possible; nevertheless, pro-inflammatory markers as well as parameters of endothelial dysfunction might serve as surrogate markers. The aim of study was to assess the correlation between the therapeutic efficacy of carvedilol and markers of endothelial dysfunction and systemic inflammation in patients with liver cirrhosis and portal hypertension. MATERIAL AND METHODS: Thirty-six patients with cirrhosis and portal hypertension were given carvedilol, 25 mg q.i.d. for 30 days. Hepatic venous pressure gradient (HVPG) and biochemical determinations were performed prior to and after the treatment. Eight healthy individuals served as controls for comparison of biochemical markers. RESULTS: In the whole group of cirrhotic patients, HVPG decreased from 17.7+/-3.8 to 14.9+/-4.8 mmHg (p<0.001). Complete response was seen in 15 patients (42%). Baseline serum levels of E-selectin were significantly higher in responders than in non-responders (119.8+/-70.6 versus 52.6+/-25.7 ng/ml; p=0.023) and in controls (28.8+/-22.2 ng/ml; p=0.004). Furthermore, baseline TNF-alpha levels were significantly higher in responders than in non-responders (22.8+/-15.7 versus 7+/-8.9; p=0.047) and in controls (5.5+/-5.9 pg/ml; p=0.005). Serum levels of ICAM-1 showed the same trend (4360+/-2870 versus 2861+/-1577 versus 651+/-196 ng/ml), although differences did not reach statistical significance. CONCLUSIONS: Markers of systemic inflammation and endothelial dysfunction seem to predict the hypotensive effect of carvedilol on portal hypertension in patients with liver cirrhosis and may be useful in the assessment of the efficacy of the therapy.