Background Prior studies suggested that obstructive sleep apnea (OSA) promotes recurrence of arrhythmia in patients after atrial fibrillation (AF) ablation. Methods In this prospective, long-term, observational study, we enrolled 290 consecutive patients admitted for AF ablation. Prior to the ablation, all patients underwent a polygraphy sleep study for the diagnosis of OSA. After the procedure, patients were followed up for mean time of 30 months for AF reoccurrence. OSA was diagnosed when apnea–hypopnea index (AHI) was ≥5. Patients were subsequently divided into groups according to the OSA severity: mild OSA (AHI 5–15/h), moderate OSA (AHI >15 and ≤30/h), and severe (AHI >30/h). Results After excluding patients disqualified from the procedure, and those with central sleep apnea, the study population consisted of 251 patients, mean age 57.6 years [163 (64.9 %) male]. OSA was present in 115 (45.8 %) patients, while in 137 (54.6 %) cases, we observed reoccurrence of AF. Recurrence was more often in patients with, than without, OSA (65.2 vs. 45.6 %; p = 0.003). We also observed that along with rising OSA severity rose also the number of patients in whom AF was detected during the follow-up period (45.6 vs. 66.2 vs. 57.6 vs. 81.8 %; p = 0.005; for non-OSA, mild, moderate, and severe, respectively). Conclusions OSA is highly prevalent in AF patients. The presence of OSA lowers chances on successful AF ablation. Early screening, and treatment for OSA in AF patients, may improve low success rates of AF ablation procedures.

In recent years, the diagnosis and understanding of nonalcoholic fatty liver disease (NAFLD), recently redefined as metabolic dysfunction-associated steatotic liver disease (MASLD), and its relationship with cardiovascular diseases (CVD) are gaining better understanding. As MASLD shares common...

Cardiovascular diseases are the leading cause of death worldwide. One of the most important diseases in this group is myocardial infarction (MI). According to the universal definition developed by the European Society of Cardiology (ESC), MI is divided into five main types based on its cause. Type 2 MI is secondary to ischaemia due to either increased demand or decreased supply of oxygen (for example due to coronary artery spasm, anaemia, arrhythmia, coronary embolism, hypertension, or hypotension). To assess the occurrence and aetiology of type 2 acute MI (AMI), and to describe the clinical characteristics and prognosis of study patients. Into a retrospective study, we enrolled 2,882 patients in the Cardiology Department with an initial diagnosis of AMI between 2009 and 2012. Diagnosis of AMI was made based on ESC criteria. In all patients, coronary angiography was performed in order to exclude haemodynamically significant coronary lesions. Among 2,882 patients hospitalised in the described time period, 58 (2%) patients were diagnosed with type 2 AMI.The mean age of the study group was 67.3 ± 13.2 years; and the majority of the study group, 60.3%, were women. Out of them, 23 (39.6%) patients experienced AMI due to coronary artery spasm, 15 (25.9%) due to arrhythmias, 11 (19%) due to severe anaemia, and nine (15.5%) due to hypertension, without significant coronary artery disease. 42 (72.4%) patients, were diagnosed as non-ST-segment elevation MI, 14 (24.1%) as ST-segment elevation MI, and two (3.5%) as AMI in the presence of ventricular paced rhythm. History of classical cardiovascular risk factors including hypertension, diabetes, dyslipidaemia, family history of heart diseases, and smoking was reported in 42 (72.4%), 14 (24.1%), 23 (39.7%), 24 (41.4%), and 16 (27.6%) cases, respectively. All-cause 30-day mortality rate was 5.2%, and six-month was 6.9%. Type 2 AMI patients were more often female, and they were more often diagnosed as non-ST-segment elevation MI. The prevalence of classical cardiovascular risk factors in this subgroup of patients was very high. The leading cause of AMI was coronary artery spasm.

It is expected that use of adult multipotential mesenchymal stem cells (MSCs) for bone tissue engineering (TE) will lead to improvement of TE products. Prior to clinical application, biocompatibility of bone TE products need to be tested in vitro and in vivo. In orthopedic research, sheep are a well-accepted model due to similarities with humans and are assumed to be predictive of human outcomes. In this study we uncover differences between human and ovine bone marrow–derived MSCs (BMSCs) and adipose tissue–derived MSCs (ADSCs) in response to osteogenic media. Osteogenic differentiation of BMSCs and ADSCs was monitored by alkaline phosphatase (ALP) activity and calcium deposition. Mineralization of ovine BMSC was achieved in medium containing NaH₂PO₄ as a source of phosphate ions (Pi), but not in medium containing β-glycerophosphate (β-GP), which is most often used. In a detailed study we found no induction of ALP activity in ovine BMSCs and ADSCs upon osteogenic stimulation, which makes β-GP an unsuitable source of phosphate ions for ovine cells. Moreover, mineralization of human ADSCs was more efficient in osteogenic medium containing NaH₂PO₄. These results indicate major differences between ovine and human MSCs and suggest that standard in vitro osteogenic differentiation techniques may not be suitable for all types of cells used in cell-based therapies. Since mineralization is a widely accepted marker of the osteogenic differentiation and maturation of cells in culture, it may lead to potentially misleading results and should be taken into account at the stage of planning and interpreting preclinical observations performed in animal models. We also present a cell culture protocol for ovine ADSCs, which do not express ALP activity and do not mineralize under routine pro-osteogenic conditions in vitro. We plan to apply it in preclinical experiments of bone tissue–engineered products performed in an ovine model.