Agnieszka Bednarek

Bio: Agnieszka Bednarek is an academic researcher from Jagiellonian University Medical College. The author has contributed to research in topics: QRS complex & Heart failure. The author has an hindex of 9, co-authored 31 publications receiving 222 citations. Previous affiliations of Agnieszka Bednarek include The Commonwealth Medical College.

Programmed deep septal stimulation: A novel maneuver for the diagnosis of left bundle branch capture during permanent pacing

Abstract: Introduction Permanent deep septal stimulation with capture of the left bundle branch (LBB) enables maintenance/restoration of the physiological activation of the left ventricle. However, it is almost always accompanied by the simultaneous engagement of the local septal myocardium, resulting in a fused (nonselective) QRS complex, therefore, confirmation of LBB capture remains difficult. Methods We hypothesized that programmed extrastimulus technique can differentiate nonselective LBB capture from myocardial-only capture as the effective refractory period (ERP) of the myocardium is different from the ERP of the LBB. Consecutive patients undergoing pacemaker implantation underwent programmed stimulation delivered from the lead implanted in a deep septal position. Responses to programmed stimulation were categorized on the basis of sudden change in the QRS morphology of the extrastimuli, observed when ERP of LBB or myocardium was encroached upon, as: "myocardial," "selective LBB," or nondiagnostic (unequivocal change of QRS morphology). Results Programmed deep septal stimulation was performed 269 times in 143 patients; in every patient with the use of a basic drive train of 600 milliseconds and in 126 patients also during intrinsic rhythm. The average septal-myocardial refractory period was shorter than the LBB refractory period: 263.0 ± 34.4 vs 318.0 ± 37.4 milliseconds. Responses diagnostic for LBB capture ("myocardial" or "selective LBB") were observed in 114 (79.7%) of patients. Conclusions A novel maneuver for the confirmation of LBB capture during deep septal stimulation was developed and found to enable definitive diagnosis by visualization of both components of the paced QRS complex: selective paced LBB QRS and myocardial-only paced QRS.

The V6-V1 interpeak interval: a novel criterion for the diagnosis of left bundle branch capture.

Abstract: Aims We hypothesized that during left bundle branch (LBB) area pacing, the various possible combinations of direct capture/non-capture of the septal myocardium and the LBB result in distinct patterns of right and left ventricular activation. This could translate into different combinations of R-wave peak time (RWPT) in V1 and V6. Consequently, the V6-V1 interpeak interval could differentiate the three types of LBB area capture: non-selective (ns-)LBB, selective (s-)LBB, and left ventricular septal (LVS). Methods and results Patients with unquestionable evidence of LBB capture were included. The V6-V1 interpeak interval, V6RWPT, and V1RWPT were compared between different types of LBB area capture. A total of 468 patients from two centres were screened, with 124 patients (239 electrocardiograms) included in the analysis. Loss of LVS capture resulted in an increase in V1RWPT by ≥15 ms but did not impact V6RWPT. Loss of LBB capture resulted in an increase in V6RWPT by ≥15 ms but only minimally influenced V1RWPT. Consequently, the V6-V1 interval was longest during s-LBB capture (62.3 ± 21.4 ms), intermediate during ns-LBB capture (41.3 ± 14.0 ms), and shortest during LVS capture (26.5 ± 8.6 ms). The optimal value of the V6-V1 interval value for the differentiation between ns-LBB and LVS capture was 33 ms (area under the receiver operating characteristic curve of 84.7%). A specificity of 100% for the diagnosis of LBB capture was obtained with a cut-off value of >44 ms. Conclusion The V6-V1 interpeak interval is a promising novel criterion for the diagnosis of LBB area capture.

Esc guidelines for the diagnosis and treatment of acute and chronic heart failure 2008 (ending)

Abstract: ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure 2008 (ending).

The Effect of Diaphragmatic Breathing on Attention, Negative Affect and Stress in Healthy Adults

Abstract: A growing number of empirical studies have revealed that diaphragmatic breathing may trigger body relaxation responses and benefit both physical and mental health However, the specific benefits of diaphragmatic breathing on mental health remain largely unknown The present study aimed to investigate the effect of diaphragmatic breathing on cognition, affect, and cortisol responses to stress Forty participants were randomly assigned to either a breathing intervention group or a control group The breathing intervention group received intensive training for 20 sessions, implemented over 8 weeks, employing a real-time feedback device, and an average respiratory rate of 4 breaths/minute, while the control group did not receive this treatment All participants completed pre- and post-tests of sustained attention and affect Additionally, pre-test and post-test salivary cortisol concentrations were determined in both groups The findings suggested that the breathing intervention group showed a significant decrease in negative affect after intervention, compared to baseline In the diaphragmatic breathing condition, there was a significant interaction effect of group by time on sustained attention, whereby the breathing intervention group showed significantly increased sustained attention after training, compared to baseline There was a significant interaction effect of group and time in the diaphragmatic breathing condition on cortisol levels, whereby the breathing intervention group had a significantly lower cortisol level after training, while the control group showed no significant change in cortisol levels In conclusion, diaphragmatic breathing could improve sustained attention, affect, and cortisol levels This study provided evidence demonstrating the effect of diaphragmatic breathing, a mindbody practice, on mental function, from a health psychology approach, which has important implications for health promotion in healthy individuals

Validation of non-invasive central blood pressure devices: ARTERY Society task force consensus statement on protocol standardization

Abstract: Brachial cuff blood pressure (BP) is clinically important, but may be an inaccurate substitute for central BP. Many non-invasive devices have been developed that purport to estimate central BP from peripheral artery sites, yet with no standardized guidelines; the accuracy testing of these new devices has not been undertaken in a uniform fashion with comparable protocols. This is an abridged paper describing the recommendations reached by an international task force convened to identify issues that need to be addressed and reach consensus relating to methods for assessing and reporting the accuracy (validation) of central BP devices. The recommendations are endorsed by the Association for Research into Arterial Structure and Physiology (ARTERY) Society, as well as the European Society of Hypertension (ESH) Working Group on Arterial Structure and Function, and the ESH Working Group on Blood Pressure Monitoring and Cardiovascular Variability. Researchers interested in validating central BP monitors should read the full version of the statement.

Methodology and technology for peripheral and central blood pressure and blood pressure variability measurement: Current status and future directions - Position statement of the European Society of Hypertension Working Group on blood pressure monitoring and cardiovascular variability

Abstract: Office blood pressure measurement has been the basis for hypertension evaluation for almost a century. However, the evaluation of blood pressure out of the office using ambulatory or self-home monitoring is now strongly recommended for the accurate diagnosis in many, if not all, cases with suspected hypertension. Moreover, there is evidence that the variability of blood pressure might offer prognostic information that is independent of the average blood pressure level. Recently, advancement in technology has provided noninvasive evaluation of central (aortic) blood pressure, which might have attributes that are additive to the conventional brachial blood pressure measurement. This position statement, developed by international experts, deals with key research and practical issues in regard to peripheral blood pressure measurement (office, home, and ambulatory), blood pressure variability, and central blood pressure measurement. The objective is to present current achievements, identify gaps in knowledge and issues concerning clinical application, and present relevant research questions and directions to investigators and manufacturers for future research and development (primary goal).