Second-generation cryoballoon ablation for recurrent atrial fibrillation after an index procedure with radiofrequency versus cryo: Different pulmonary vein reconnection patterns but similar long-term outcome-Results of a multicenter analysis.

INTRODUCTION: Repeated procedures are often needed for long-term success of atrial fibrillation ablation. There are scarce data regarding cryoballoon use for such procedure. METHODS AND RESULTS: We analyzed acute effect and long-term follow-up of second-generation cryoballoon ablation, performed as a repeat procedure after an index radiofrequency vs cryoballoon ablation. Sixty-one patients from three centers were included. In 36 cases radiofrequency (RF-I) and in 25 cryoballoon ablation (CB-I) was the index procedure. During redo procedure, pulmonary vein reconnection was less frequent in CB-I vs RF-I (51.5% vs 66.9%; P = 0.017). After cryoballoon, left inferior (P = 0.027) and right superior (P = 0.06) pulmonary veins were less likely to exhibit reconnection. Moreover, patients after initial RF ablation frequently presented multiple-vein reconnection (P = 0.018), while patients after cryoablation more often had only one vein reconnected (P = 0.008). During reablation procedures, all 149 reconnected veins in both groups were isolated, with no differences in procedural parameters, except for procedure time, shorter in CB-I group (65.5 vs 71.1 minutes; P = 0.04). Transient phrenic nerve palsy was the only complication in both groups (5.6% and 8.0%; ns). After mean follow-up of 15 ± 9 months, 70.3% of patients were free from atrial fibrillation (AF), with no differences between the groups (P = 0.71). In multivariate Cox-regression analysis, the persistent form of arrhythmia (P = 0.009) and relapse in the blanking period (P = 0.0004) were the only independent predictors of AF recurrence. CONCLUSIONS: The use of second-generation cryoballoon is associated with less frequent pulmonary vein reconnection compared with RF ablation. Cryoballoon is safe and effective for repeated AF ablation, regardless of the technique used for the initial procedure.

[MicroRNA--a new diagnostic tool in coronary artery disease and myocardial infarction]. / Mikro-RNA--nowe szanse diagnostyczne w chorobie niedokrwiennej i zawale serca.

Coronary artery disease remain one of the leading causes of mortality in the world, indicating the need for innovative therapies and diagnosis for heart disease. MicroRNAs (miRNAs) have recently emerged as one of the central players in regulating gene expression which implicatate in normal cardiac development and many pathological process of the cardiovascular system, including cardiac arrhythmia, heart failure, cardiac fibrosis, coronary artery disease and myocardial infarction. iRNA are small noncoding RNAs 18-23 nucleotides in length that regulate expression of target genes through sequence-specific hybridization to the 3' untranslated region of messenger RNAs and block translation. miRNAs are not only found intracellularly, but also detectable outside cells, including various body fluids (i.e. serum, plasma, saliva, urine). This review will highlight recent findings in the regulation of miRNA biogenesis and secretion, modulation of the cardiovascular pathological process in CAD and AMI and the potential as non-invasive biomarkers for cardiac ischemia.

[Matrix metalloproteinases and atherosclerosis]. / Metaloproteinazy w miazdzycy naczyn krwionosnych.

Matrix metalloproteinases (MMPs), a family of proteolytic enzymes that degrade extracellular matrix (ECM), seem to have an important role in pathogenesis of atherosclerosis. Released by inflammatory cells and smooth muscle cells, MMPs regulate the vascular remodeling process. The expression and activity of MMPs is regulated at the level of transcription by a variety of cytokines, proenzyme activation by several cellular and serum proteases, as well as by endogenous and exogenous inhibitors. Overproduction of MMPs could promote arteriosclerosis, leading to atherosclerotic plaque formation, and plaque rupture, resulting in clinical consequences such as myocardial infarction, or critical limb ischemia. Increased plasma levels of some MMPs are now regarded as potential biomarkers of atherosclerosis and cardiovascular risk. The potential significance of MMP inhibitors in atherosclerosis therapy is discussed.