Correlation between AV synchrony and device collected AM-VP sequence counter in atrioventricular synchronous leadless pacemakers: A real-world assessment.

INTRODUCTION: Micra atrioventricular (AV) provides leadless atrioventricular synchronous pacing by sensing atrial contraction (A4 signal). Real-world operation and reliability of AV synchrony (AVS) assessment using device data have not been described. The purposes of this study were to (1) assess the correlation between AVS and atrial mechanical sensed-ventricular pacing (AM-VP) percentages in patients with permanent high-degree AV block and (2) report on the real-world effectiveness of Micra AV. METHODS: The correlation between ECG-determined AVS in-clinic and device-collected %AM-VP was assessed using data from 40 patients with high-degree AV block enrolled in the Micra Atrial tRacking using a Ventricular AccELerometer (MARVEL) 2 study. A retrospective analysis to assess continuously-sampled %AM-VP since last session, device programming, and electrical parameters was performed using Micra AV transmissions from the Medtronic CareLink database. Patients with transmissions ≥180 days postimplant were included. RESULTS: Among the 40 MARVEL 2 AV block patients with a median %VP of 99.7%, AVS was highly correlated with AM-VP (median AVS 87.1%, median AM-VP 79.1%; R2 = 0.764, p < .001). The CareLink cohort included 4384 patients programmed to VDD mode. The mean A4 amplitude was 2.3 ± 1.8 m/s2 at implant and 2.3 ± 1.6 m/s2 at 28 weeks. In patients with %VP >90% (n = 1662), the median %AM-VP was 74.7%. For the full cohort, median %VP was 65.6% and median projected battery longevity was 10.5 years. CONCLUSION: In patients with a high pacing burden, %AM-VP provides a reasonable estimation of AVS. The first large real-world analysis of Micra AV patients with >90% VP showed stable atrial sensing over time with a median %AM-VP, a correlate of AVS, of 74.7%.

Comparability between Computed Tomography Morphological Vascular Parameters and Echocardiography for the Assessment of Pulmonary Hypertension in Patients with Severe Aortic Valve Stenosis-Results of a Multi-Center Study.

Background: Computed tomography (CT) of the aorta and cardiac vessels, which is performed in patients with severe aortic valve stenosis (AS) before transcatheter aortic valve replacement (TAVR), offers the possibility of non-invasive detection of pulmonary hypertension (PH), for example, by determining the diameter of the main pulmonary artery (PA), the right pulmonary artery (RPA) or the left pulmonary artery (LPA). An improvement of the significance of these radiological parameters is often achieved by indexing to the body surface area (BSA). The aim of this study was to compare different echocardiographic systolic pulmonary artery pressure (sPAP) values with radiological data in order to define potential clinical cut-off values for the presence or absence of PH. Methods: A total of 138 patients with severe AS undergoing TAVR underwent pre-interventional transthoracic echocardiography with determination of sPAP values and performance of CT angiography (CTA) of the aorta and femoral arteries. Radiologically, the PA, RPA, LPA, and ascending aorta (AA) diameters were obtained. Vascular diameters were not only indexed to BSA but also ratios were created with AA diameter (for example PA/AA-ratio). From these CT-derived vascular parameters, AUROC curves were obtained regarding the prediction of different sPAP values (sPAP 40−45−50 mmHg) and finally correlation analyses were calculated. Results: The best AUROC and correlation analyses were generally obtained at an sPAP ≥ 40 mmHg. When considering diameters alone, the PA diameter was superior to the RPA and LPA. Indexing to BSA generally increased the diagnostic quality of the parameters, and finally, in a synopsis of all results, PA/BSA had the best AUC 0.741 (95% CI 0.646−0. 836; p < 0.001; YI 0.39; sensitivity 0.87; specificity 0.52) and Spearman's correlation coefficient (r = 0.408; p < 0.001) at an sPAP of ≥40 mmHg. Conclusions: Features related to pulmonary hypertension are fast and easily measurable on pre-TAVR CT and offer great potential regarding non-invasive detection of pulmonary hypertension in patients with severe AS and can support the echocardiographic diagnosis. In this study, the diameter of the main pulmonary artery with the additionally determined ratios were superior to the values of the right and left pulmonary artery. Additional indexing to body surface area and thus further individualization of the parameters with respect to height and weight can further improve the diagnostic quality.

Intraprocedural dynamics of cardiac conduction during transcatheter aortic valve implantation: Assessment by simultaneous electrophysiological testing.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) is an established treatment for patients with severe aortic stenosis and high to intermediate surgical risk. However, the proximity of the conduction system to the prosthesis landing zone bears the risk of atrioventricular conduction disorders. The underlying pathophysiology is not fully understood. OBJECTIVE: The purpose of this study was to characterize the impact of TAVI on the conduction system as assessed by simultaneous electrophysiological testing. METHODS: AH and HV intervals and QRS duration were measured using a quadripolar His catheter and surface electrocardiogram in 108 patients at baseline (BL), after balloon predilation (timepoint 1 [T1]), after implantation of the valve prosthesis (T2), and after postdilation, if deemed necessary (T3). RESULTS: Between BL and T2, significant increases of HV interval and QRS duration were observed, with a mean delta of +12.4 ms and +32.7 ms, respectively. Both balloon predilation and valve implantation had an impact on infranodal conduction. No significant increase of AH intervals was documented. The increase of QRS duration led to left bundle branch block (LBBB) in 57 patients (52.8%). Implantation depth positively correlated with QRS prolongation (ρ = 0.21, P = .042) but not with changes of AH or HV interval (ρ = -0.03, P = .762; and ρ = 0.15, P = .130, respectively). CONCLUSION: Electrophysiological testing during TAVI shows impairment of infranodal atrioventricular conduction by balloon predilation and valve implantation. This impairment is positively correlated with valve implantation depth and results in an increase of QRS duration with mainly LBBB pattern on surface electrocardiogram.

Self-assessment of medical students and young physicians in training : Self-confidence of clinical competencies and working or learning environment.

BACKGROUND: In 2015 medical training regulations have been restructured for postgraduate medical training in Austria resulting in a significant shortening of the training period. Furthermore, a restriction of working hours for physicians to 48 h per week was implemented affecting the framework of postgraduate medical training. The aim of this study was to obtain a self-assessment of students and young physicians in Austria regarding their self-confidence in clinical skills and their working and learning environment. METHODS: In this study 6th year medical students, physicians in their basic training (common trunk), physicians in family medicine training, and residents in their first 18 months of training were asked to participate in a survey. Self-reported data were collected for five different prespecified domains (communication, motor skills, knowledge, documentation, and emergency). RESULTS: In all domains, self-confidence increased significantly during medical training. Analysis further revealed better results of residents compared with all other groups in all domains, whereas physicians in family medicine training only rated themselves better in the documentation domain (p = 0.010); however, the interest in family medicine was low, even among physicians in family medicine training. The workload significantly increased during medical education, with the highest stress levels for physicians in family medicine training and residents (p = 0.001). CONCLUSIONS: Self-confidence of young physicians but also their stress levels increased during the medical training. Further studies are needed to answer the question why the interest in family medicine was so unexpectedly low in this cohort.

Economic assessment of traditional surgical intervention versus use of a new innovative radiofrequency based surgical system in device replacements.

INTRODUCTION: Intra-operative complications like mechanical damages to the leads, infections and hematomas during generator replacements of implantable pacemakers and defibrillators contribute to additional costs for hospitals. The aim of this study was to evaluate operation room use, costs and budget impact of generator replacements using either a traditional surgical intervention (TSI) with scissors, scalpel and electrocautery vs. a new radiofrequency energy based surgical system, called PEAK PlasmaBladeTM (PPB). MATERIALS AND METHODS: We conducted a retrospective analysis of a population including 508 patients with TSI and 254 patients with PPB who underwent generator replacement at the Kepler University Hospital in Linz or the St. Josef Hospital in Braunau, Austria. The economic analysis included costs of resources used for intra-operative complications (lead damages) and of procedure time for TSI vs. PPB. RESULTS: Proportion of males, mean age and type of generator replaced were similar between the two groups. Lead damages occurred significantly more frequent with TSI than with PPB (5.3% and 0.4%; p< 0.001) and the procedure time was significantly longer with TSI than with PPB (47.9±24.9 and 34.1±18.1 minutes; p<0.001). Shorter procedure time and a lower rate of lead damages with PPB resulted in per patient cost savings of €81. Based on estimated 2,700 patients annually undergoing generator replacement in Austria, the use of PPB may translate into cost savings of €219,600 and 621 saved operating facility hours. CONCLUSION: PPB has the potential to minimize the risk of lead damage with more efficient utilization of the operating room. Along with cost savings and improved quality of care, hospitals may use the saved operating room hours to increase the number of daily surgeries.

An electrical plasma surgery tool for device replacement--retrospective evaluation of complications and economic evaluation of costs and resource use.

BACKGROUND: Device replacements bear many potential risks for patients. Electrocautery should be used cautiously because of heating of the cautery tip which may lead to insulation melting. The PEAK PlasmaBlade™ (Medtronic Inc., Minneapolis, MN, USA) uses a novel technology to cut tissue. The objective of this study was to evaluate if this instrument is less destructive and can decrease complications and shorten procedure times. METHODS AND RESULTS: Two groups were compared: in group 1, surgery was done with scissors and conventional electrocautery, whereas the PEAK PlasmaBlade™ was used in group 2. Procedure time and complication rates were retrospectively investigated. Group 1 comprised 509 patients, while group 2 consisted of 102 patients. Procedure time in group 2 was significantly shorter with 28.4 ± 8.9 minutes than in group 1 with 47.5 ± 24.5 minutes (P < 0.001). The hospital stay was also reduced (2.1 ± 2.2 days versus 3.1 ± 2.4 days, P < 0.001). One major complication occurred in only 2.4% (two patients) of group 2 and in 6.9% (35 patients) of group 1. There were no damaged leads in group 2 compared to 5.7% in group 1 (P = 0.008). Cost analyses showed that the use of The PEAK PlasmaBlade™ instead of conventional electrocautery resulted in cost savings of €120/patient. CONCLUSION: Device replacement is associated with a notable complication risk. Our investigation showed that a new device for generator replacement resulted in significantly reduced procedure time and length of hospital stay while completely avoiding lead damage, which translated into considerable cost savings in a real world setting.