Background: Right ventricular apical pacing has been used since the early years of pace-makers, despite the fact that it determined nonphysiological ventricular depolarization. As medical technologies developed, septal lead implantation became feasible, in order to outrun the above mentioned inconveniences. The question whether the apical or septal lead position is better still gives rise to a lot of controversies. Different echocardiographic parameters are currently used to assess the impact of specific sites of stimulation on ventricular function. The aim of the study was to determine which of the followed synchronicity parameters varied significantly during apical stimulation, compared to septal stimulation in patients requiring single chamber pacing.
Material and method: Fifty-nine patients admitted between January 1st - December 31st 2012 either for battery replacement or for first implant of a single chamber pace-maker were included in this prospective study. Thirty-eight of them had the lead placed in the apex of the right ventricle and 21 on the interventricular septum. All were subjected to echocardiografic examination after device implantation. Measurements included complete chamber and valvular assessment, apart from the synchronicity evaluation, that comprised interventricular mechanical delay (IVMD), septal to posterior wall delay (SPWMD) and electro systolic delays (ESD), in order to assess the presence and compare the relevance of interventricular and intraventricular dissyncrony. All the investigations were in accordance with the Declaration of Helsinki.
Results: Although preejection times were significantly different, there were no statistically significant differences (p = 0.06) between the values of IVMD in the two groups, as well as regarding the longitudinal intraventricular dyssynchrony expressed by ESD. Significant differences appeared though, between the values of SPWMD, reflecting the fact that radial intraventricular dissyncrony is present in apical stimulation.
Conclusions: During apical right ventricular pacing, radial intraventricular dissyncrony appears, while in the case of septal pacing this parameter is close to normal. Surprisingly, although right ventricular pacing determines interventricular and longitudinal intraventricular dissincrony, we found no significant differences in this respect, between apical and septal pacing.
Iron deficiency and anemia affect approximately half of the chronic heart failure patients and they are associated with increased hospitalization rate, lower functional capacity, lower quality of life, and higher mortality. The exact mechanism of iron deficiency in heart failure patients is still not fully understood. Current guidelines recommend ferritin as the most accurate serum biomarker for the diagnosis of iron deficiency. The use of erythropoiesis-stimulating agents is no longer recommended because of the lack of improvement on mortality or hospital readmission rate, and it was associated with a higher rate of thromboembolic events. Intravenous iron replacement therapy is safe and generally well tolerated, with fewer side effects compared to oral administration. Large randomized studies with ferric carboxymaltose demonstrated its effectiveness and superiority to oral administration, and it was associated with a decreased rate of hospitalization rate and worsening heart failure, and improvement of functional capacity and quality of life. Intravenous iron supplementation for chronic heart failure is strongly recommended by European guidelines. Further studies are needed for a better knowledge of this complex pathology and determination of the long-term safety and effectiveness of iron administration in chronic heart failure patients. .
Recent studies demonstrated that despite restoration of the sinus rhythm, patients with a positive history of atrial fibrillation (AF) are still at risk of thromboembolic events. The primary objective of this study is to identify new imaging-derived biomarkers provided by modern imaging technologies, such as cardiac computed tomography angiography, delayed enhancement magnetic resonance imaging, or speckle tracking echocardiography, as well as hematological biomarkers, associated with the risk of intracavitary thrombosis in patients with AF, in order to identify the imaging-derived characteristics associated with an increased risk of cardioembolic events. Imaging data collected will be post-processed using advanced techniques of computational modeling, in order to fully characterize the degree of structural remodeling and the amount of atrial fibrosis. The primary endpoint of the study is represented by the rate of thromboembolic events. The rate of cardiovascular death, the rate of major adverse cardiovascular events, and the rate of AF recurrence will also be determined in relation to the degree of structural remodeling and atrial fibrosis.
Atrial fibrillation is the most frequent arrhythmia in adults, becoming more frequent with age. Recent clinical studies demonstrated that epicardial fat is linked with atrial fibrillation induction and recurrence. The arrhythmogenic mechanism consists in the fact that the epicardial adipose tissue is metabolically active, inducing local inflammation and enhancing the oxidative stress, which lead to atrial fibrillation as well as atherosclerosis. Having metabolic activity and secreting various anti- and pro-inflammatory biomarkers, the fat surrounding the heart has been linked to the complex process of coronary plaque vulnerabilization. This clinical update aims to summarize the role of epicardial adipose tissue in the pathogenesis, persistence, and severity of atrial fibrillation.