Beta-blockers for the treatment of arrhythmias: Bisoprolol - a systematic review.

OBJECTIVES: Beta-blockers have long been successfully used for the treatment of both supraventricular and ventricular arrhythmias. However, differences exist between their chemical structure, pharmacokinetic and pharmacodynamic properties (absorption, bioavailability, metabolism, hydrophilic or lipophilic character, selective or non-selective nature, the presence or absence of intrinsic sympathomimetic activity), which may confer different antiarrhythmic properties to different beta-blockers. The aim of this study was to analyze the current existing evidence for bisoprolol for the treatment of both supraventricular and ventricular arrhythmias. MATERIAL AND METHODS: Using the keywords "bisoprolol" and "arrhythmias" or "atrial fibrillation" or "ventricular tachycardia" or "premature ventricular complexes" or "ventricular fibrillation", the Medline database was searched for articles in English or French until April 2020 assessing the role of bisoprolol in the treatment of arrhythmias. Data was then analyzed according to the type of arrhythmia treated and the quality of evidence using the GRADE approach. RESULTS: A total of 325 studies were identified, of which 28 were considered relevant to the current topic. Among these studies, 19 assessed the role of bisoprolol for the treatment of supraventricular arrhythmias, 8 its role in treating ventricular arrhythmias and 1 its role in supraventricular and ventricular arrhythmias. The quality of evidence varied from low (7 studies) to high (5 studies). CONCLUSION: Current evidence exists supporting the use of bisoprolol for the treatment of supraventricular arrhythmias, especially for rate control during atrial fibrillation. Evidence also exists for its efficacy in the treatment of ventricular arrhythmias, both in primary and in secondary prevention.

Chronic oral trimethylamine-N-oxide administration induces experimental incipient atherosclerosis in non-genetically modified mice.

Atherosclerosis is a chronic inflammatory disease of the arterial wall involving inflammation, redox imbalance, and impaired cholesterol transport. A high level of trimethylamine-N-oxide (TMAO) produced by meat and fat metabolism are involved in atherosclerosis development, but the exact relationship with inflammation is not completely clear. The study aimed to identify a possible association between TMAO; atherosclerotic changes in the aortic root; oxidative stress; and inflammation quantified by highly sensitive C-reactive protein (hsCRP), tumor necrosis factor alpha (TNF-α), and interleukin-1beta (IL-1ß) levels. TMAO dihydrate was administered via gastric gavage to 20 male Wistar rats for 90 days; one separate group received vehicle. The TMAO-treated animals were divided into two groups: one group received a low dose of TMAO (20 mg/day) and the other group received a high dose of TMAO (40 mg/day). Malondialdehyde (MDA), proinflammatory markers - IL-1ß, TNF-α, and hsCRP, total cholesterol, high-density lipoprotein (HDL)-cholesterol, triglycerides, and glucose were assessed 30 and 90 days after TMAO administration. Additionally, conventional histopathology and immunohistochemistry for collagen I distribution were performed. MDA, hsCRP, TNF-α, and IL-1ß levels increased after 90 days of TMAO administration in conjunction with significant changes suggestive of incipient atherosclerosis and inflammation of the aortic root. The increase was higher in the group treated with 40 mg/day TMAO compared with the group treated with 20 mg/day TMAO. Additionally, blood levels of TMAO were significantly correlated with hsCRP, TNF-α, IL-1ß levels, but also with MDA, low HDL-cholesterol levels, and high triglyceride levels. The increase in MDA and inflammatory cytokines and modification of lipid metabolism markers may explain the pro-atherogenic effect of TMAO.

Correlations between the surface ECG and the intracavitary electrocardiogram in typical atrial flutter.

UNLABELLED: Typical atrial flutter (cavo-tricuspid isthmus-dependent) has as an electrophysiological substrate a macro-reentry circuit localized in the right atrium. Depending on the right atrial depolarization sequence, the rotation of the macro-reentry circuit can be counterclockwise (with an inferior to superior activation of the right atrium free wall and superior to inferior activation of the interatrial septum), characterized by negative F waves in inferior leads (DII, DIII, aVF) and V6, and positive in V1 on the surface electrogram (ECG), or clockwise (with a superior to inferior activation of the right atrium free wall and inferior to superior activation of the interatrial septum) characterized by positive F waves in inferior leads (DII, DIII, aVF) and V6, and negative in V1. Nevertheless, it is considered that for the diagnosis of the typical or atypical nature of this arrhythmia, the surface ECG has limited value. The purpose of this study was to compare the relationship between the flutter rotation sequence determined by the intracavitary electrogram and the morphology of the F waves on the surface ECG. METHODS: The study included 387 patients admitted to the Cardiology - Rehabilitation Hospital from Cluj-Napoca between January 2007 and May 2010, diagnosed with typical atrial flutter during an electrophysiological study. Using the intracavitary electrograms the flutter rotation sequence was determined (clockwise or counterclockwise). The F waves' aspect on the surface ECG in leads DII, DIII, aVF, aVL, V1 and V6 was then analyzed. RESULTS: One hundred and fifty two patients (39.3%) were diagnosed with clockwise atrial flutter and 235 patients (60.7%) with counterclockwise atrial flutter. The positive predictive value (PPV) of negative F waves in inferior leads and positive in V1 was, in the case of counterclockwise atrial flutter 98%; the negative predictive value (NPV) was 79%; sensitivity (Se) was 83% and specificity (Sp) was 97%. For typical clockwise atrial flutter, the PPV of the positive F waves in the inferior leads and negative in V1 was 94% (p < 0.001); the NPV was 85%; Se was 73% and Sp was 97%. CONCLUSION: The surface ECG has a high value in determining the macroreentry circuit rotation sequence in the case of typical atrial flutter.

Assessment of the correlation between two defining criteria for bidirectional isthmic block in the ablation of typical atrial flutter.

BACKGROUND: A complete, bidirectional conduction block in the cavotricuspid isthmus (CTI) represents the end-point of the typical atrial flutter ablation. We investigated the correlation between two criteria for successful ablation, one based on the atrial bipolar electrogram morphology before and after complete CTI conduction block, compared to the standard criteria of differential pacing and reversal in the right atrial depolarization sequence during coronary sinus (CS) pacing. METHOD: We conducted a retrospective study in 111 patients (81 males, average age 62±10 years) who underwent an atrial flutter ablation during September 2007 - July 2009 in the Cardiology - Rehabilitation Hospital, UMF Cluj-Napoca. We assessed the presence of a bidirectional block at the end of the procedure using the standard criteria. We then analyzed the morphology of the bipolar atrial electrograms adjacent to the ablation line, before and after CTI conduction block. RESULTS: A change from a qRs morphology to a rSr' morphology when pacing from the coronary sinus and from a rsr' morphology to a QRS morphology when pacing from the low-lateral right atrium was associated with a CTI conduction block. Sensitivity (Se), specificity(Sp), positive predictive value (PPV), negative predictive value (NPV) were 96%, 89%, 99% and 67% respectively. CONCLUSION: Our study suggests that the analysis of the atrial bipolar electrogram next to the ablation line before and after CTI ablation may be used as a reliable criterion to validate CTI conduction block due to its high sensitivity, specificity and positive predictive value.

The role of radiofrequency ablation as a first line therapy in the treatment of atrial flutter.

UNLABELLED: Cavo-tricuspid isthmus radiofrequency (RF) ablation is an efficient option in the treatment of atrial flutter. In the case of a well-tolerated, first episode of atrial flutter, it has a class II indication, level of evidence B, the current first-line therapeutic option being electrical cardioversion, pharmacological cardioversion or atrial overdrive pacing followed by long-term antiarrhythmic therapy. The purpose of this study was to evaluate, in a prospective manner, the recurrence rate of these two different therapeutic options after the treatment of a first episode of atrial flutter. MATERIAL AND METHODS: Between January 2007 and May 2009, for 99 patients admitted to the hospital for a first episode of atrial flutter, cardioversion was attempted either by RF ablation (group 1-42 patients), or by electrical cardioversion, pharmacological cardioversion or atrial overdrive pacing followed by long-term Amiodarone therapy (group 21-57 patients). We compared the recurrence rate of atrial flutter in the 2 groups after a follow-up period of one year. RESULTS: In group 1, sinus rhythm was achieved in all patients, with bidirectional isthmic block being obtained for 37 patients (88.1%). In group 2, conversion to sinus rhythm was obtained in all cases. The recurrence rate was 6 times higher in group 2 vs group 1 (57.9% = 33 patients vs 9.5% = 4 patients) (p = 0.01). CONCLUSION: RF ablation should be considered as a therapeutic option in the treatment of the first episode of atrial flutter, due to its significant efficiency in maintaining sinus rhythm and to its low recurrence rate.

Cardiac peptides during exercise test in ischemic and non-ischemic heart failure patients.

BACKGROUND: Cardiac peptides are increased at rest in heart failure patients representing a useful diagnostic tool for this condition. Recently it has been demonstrated that cardiac peptides increase also during myocardial ischemia. Cardiac peptides increase during exercise in heart failure patients, but it has not been established yet if the increase is the same in ischemic and nonischemic patients. METHODS: There were studied 50 heart failure patients, 32 ischemic and 18 nonischemic, 35 males and 15 females aged 61.8 +/- 11.61 after the relief of congestive syndrome, which was submitted to a symptom-limited exercise stress test on a cycloergometer. Blood samples were obtained at rest and at a peak effort and the plasmatic values of NT-proBNP (NV<250 fmoles/mL) and of NT-proANP (NV<1950 fmoles/mL) were determined using the ELISA method. RESULTS: At rest, both NT-proBNP and NT-proANP were more increased in nonischemic (1104.33 +/- 730; 3275.55 +/- 3424) than in ischemic patients (685.68 +/- 452.01, 2265.0 +/- 2552.32) with significant differences only for NT-proBNP (p=0.016). During exercise NT-proBNP increase from 836.40 +/- 596.34 to 1403.92 +/- 2126.21 and NT-proANP from 2628.80 +/- 2903.41 to 3701.30 +/- 3237.76, the final values being again more increased in nonischemic patients (NT-proBNP-2945.44 +/- 3257.89; NT-proANP-3174 +/- 2905); for NT-proBNP p<0.05. The results suggest that the stretching effect during exercise is more increased at the ventricular level in comparison with the atrial level (67% increase for NT-proBNP and only 40% for NT-proANP). Surprisingly, myocardial ischemia does not increase additionally cardiac peptides either at rest or during exercise. Our data suggest that the intracardiac pressure is more important than ischemia in determining the increase of cardiac peptides in heart failure patients because the left ventricular ejection fraction was lower in nonischemic patients (40.03 +/- 5.5 vs 38.11 +/- 4.07). CONCLUSION: Cardiac peptides are increased, both at rest and during exercise, in nonischemic heart failure patients in comparison with ischemic ones, probably in relationship with the lower left ventricular systolic function.

Chlamydia pneumoniae antibodies and inflammatory reaction in patients with ischemic heart disease.

We studied the relationship between Chlamydia pneumoniae antibodies, C-reactive protein (CRP) and interleukine 8 (IL-8) in 87 patients with ischemic heart disease: 29 patients with acute myocardial infarction, 18 patients with unstable angina pectoris and 40 patients with stable effort angina. We determined in all patients IgG and IgA antibodies to Chlamydia pneumoniae, CRP and IL-8. Species specific antibodies to Chlamydia pneumoniae (IgG and IgA) were detected by indirect ELISA technique (Savyon Diagnostics Ltd, Israel). Interleukine-8 measured by a commercially available ELISA kit (CLB, Amsterdam, The Netherlands). CRP was determined by radial immunodiffusion (Mancini). The IgG antibodies were present in 25 patients (29%), the greatest percentage being noted in patients with unstable angina pectoris (50%). The IgA antibodies were present, as a sign of chronic Chlamydia pneumoniae infection, in 56% of the patients with IgG antibodies. CRP was positive in 52% of the 25 patients with positive IgG antibodies, but in only 34% of the 62 patients without IgG antibodies (p < 0.01). IL-8 was positive in 12% of the patients with IgG antibodies, and in 21% of the patients without IgG antibodies but the difference is not significant (p > 0.05). It is concluded that there is a relationship between the presence of the Chlamydia pneumoniae infection and inflammatory reaction in patients with ischemic heart disease, but the neutrophils are not implied in this process.

[The primary prevention of arterial hypertension. A meta-analysis of controlled clinical studies]. / Preventia primara a hipertensiunii arteriale. Meta-analiza studiilor clinice controlate.

OBJECTIVE: To assess the efficacy of non pharmacological primary prevention of hypertension. METHODS: Analysis of all the available trials with a minimal one-year follow-up and one recently study with 8 weeks follow-up. The outcomes consisted in blood pressure changes and incidence of hypertension at the end of the study. RESULTS: Five reviewed randomized controlled trials with a minimal one year follow-up and one recently study with eight weeks follow-up assessed the following intervention: advice about sodium restriction, weight reduction, physical exercise and relaxation, a diet rich in fruits vegetables and low fat dairy foods. All the results were available according to the "intention to treat principle". The feasibility appeared to be initially good, but decreased with time, confirming the difficulty of long term prevention. The prevention effect was mild with a decrease in hypertension incidence of a few percent (2%) and blood pressure decrease of only a few mmHg reduction (mean of 3 mmHg). Three community studies were reviewed. The prevention interventions were carried out on entire populations. The feasibility was bad (great number of lost-follow-up). The results on the blood pressure incidence were available in only one study and the blood pressure decrease estimates were heterogeneous, so the results cannot be generalized. CONCLUSION: The primary prevention of hypertension shows disappointing results when the intervention duration is above one year. It leaves little hope for a significant effect on blood pressure dependent cardiovascular events.