-
JACC. Clinical Electrophysiology Sep 2021This study sought to assess the predictive value of the proposed electrocardiogram and intracardiac electrogram characteristics for confirmation of left bundle branch...
OBJECTIVES
This study sought to assess the predictive value of the proposed electrocardiogram and intracardiac electrogram characteristics for confirmation of left bundle branch (LBB) capture.
BACKGROUND
Previously proposed criteria to distinguish left bundle branch pacing (LBBP) and left ventricular septum (LVS) pacing (LVSP) have not been fully validated.
METHODS
A His bundle pacing lead, an LBBP lead, and a multielectrode catheter at the LVS were placed. Direct LBB capture was defined as demonstration of retrograde His potential on the His bundle pacing lead and/or anterograde left conduction system potentials on the multielectrode catheter during LBBP. The routinely used parameters-His, LBB potential, time from stimulus to peak ventricular activation (Stim-LVAT), and paced QRS morphology during LVSP and LBBP at various depths and outputs were analyzed.
RESULTS
Thirty patients (21 non-left bundle branch block [LBBB], 9 LBBB) who demonstrated direct LBB capture using the defined criteria were included. The proportion of paced right bundle branch block was 100% during LBB capture in all patients compared to 23.4% in non-LBBB and 44.4% in LBBB during LVSP. LBB potential was recorded in all patients during intrinsic rhythm (non-LBBB group) or His corrective pacing in LBBB. Paced QRS duration was longer during selective LBBP compared to nonselective LBBP or LVSP only. All patients with characteristics of selective LBBP or abrupt decrease in Stim-LVAT of ≥10 ms demonstrated LBB capture.
CONCLUSIONS
Direct LBB capture can be confirmed by recording retrograde His potential and anterograde left conduction system potentials. Abrupt decrease in Stim-LVAT of ≥10 ms and demonstration of selective LBBP could be used as simple criteria to confirm LBB capture.
Topics: Bundle of His; Bundle-Branch Block; Cardiac Pacing, Artificial; Heart Rate; Humans; Ventricular Septum
PubMed: 33933414
DOI: 10.1016/j.jacep.2021.02.018 -
Europace : European Pacing,... Jan 2022We 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...
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.
Topics: Bundle of His; Cardiac Pacing, Artificial; Electrocardiography; Heart Conduction System; Humans; Ventricular Septum
PubMed: 34255038
DOI: 10.1093/europace/euab164 -
Anatomical Record (Hoboken, N.J. : 2007) Jan 2019The complete division of the atrial cavity by a septum, resulting in a left and right atrium, is found in many amphibians and all amniotes (reptiles, birds, and... (Review)
Review
The complete division of the atrial cavity by a septum, resulting in a left and right atrium, is found in many amphibians and all amniotes (reptiles, birds, and mammals). Surprisingly, it is only in eutherian, or placental, mammals that full atrial septation necessitates addition from a second septum. The high incidence of incomplete closure of the atrial septum in human, so-called probe patency, suggests this manner of closure is inefficient. We review the evolution and development of the atrial septum to understand the peculiar means of forming the atrial septum in eutherian mammals. The most primitive atrial septum is found in lungfishes and comprises a myocardial component with a mesenchymal cap on its leading edge, reminiscent to the primary atrial septum of embryonic mammals before closure of the primary foramen. In reptiles, birds, and mammals, the primary foramen is closed by the mesenchymal tissues of the atrioventricular cushions, the dorsal mesenchymal protrusion, and the mesenchymal cap. These tissues are also found in lungfishes. The closure of the primary foramen is preceded by the development of secondary perforations in the septal myocardium. In all amniotes, with the exception of eutherian mammals, the secondary perforations do not coalesce to a secondary foramen. Instead, the secondary perforations persist and are sealed by myocardial and endocardial growth after birth or hatching. We suggest that the error-prone secondary foramen allows large volumes of oxygen-rich blood to reach the cardiac left side, needed to sustain the growth of the extraordinary large offspring that characterizes eutherian mammals. Anat Rec, 302:32-48, 2019. © 2018 The Authors. The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.
Topics: Animals; Atrial Septum; Biological Evolution; Embryo, Mammalian; Humans
PubMed: 30338646
DOI: 10.1002/ar.23914 -
Turk Kardiyoloji Dernegi Arsivi : Turk... Jun 2018
Topics: Cardiac Surgical Procedures; Cardiomyopathy, Hypertrophic; Catheter Ablation; Heart Septum; Humans
PubMed: 29853690
DOI: 10.5543/tkda.2018.09076 -
CMAJ : Canadian Medical Association... Feb 2021
Topics: Adult; COVID-19; Echocardiography; Electrocardiography; Heart Septum; Humans; Magnetic Resonance Imaging; Male; Myocardial Infarction; SARS-CoV-2; Thrombosis
PubMed: 33526551
DOI: 10.1503/cmaj.202106-f -
Herzschrittmachertherapie &... Sep 2022To understand the position of a pacing lead in the right ventricle and to correctly interpret fluoroscopy and intracardiac signals, good anatomical knowledge is... (Review)
Review
To understand the position of a pacing lead in the right ventricle and to correctly interpret fluoroscopy and intracardiac signals, good anatomical knowledge is required. The right ventricle can be separated into an inlet, an outlet, and an apical compartment. The inlet and outlet are separated by the septomarginal trabeculae, while the apex is situated below the moderator band. A lead position in the right ventricular apex is less desirable, last but not least due to the thin myocardial wall. Many leads supposed to be implanted in the apex are in fact fixed rather within the trabeculae in the inlet, which are sometimes difficult to pass. In the right ventricular outflow tract (RVOT), the free wall is easier to reach than the septal due to the fact that the RVOT wraps around the septum. A mid-septal position close to the moderator band is relatively simple to achieve and due to the vicinity of the right bundle branch may produce a narrower paced QRS complex. Special and detailed knowledge is necessary for His bundle and left bundle branch pacing.
Topics: Cardiac Pacing, Artificial; Electrocardiography; Heart Conduction System; Heart Ventricles; Humans; Ventricular Septum
PubMed: 35763099
DOI: 10.1007/s00399-022-00872-w -
International Heart Journal 2021
Topics: Bundle of His; Bundle-Branch Block; Humans; Ventricular Septum
PubMed: 33518650
DOI: 10.1536/ihj.20-771 -
The Journal of Thoracic and... Mar 2021
Topics: Atrial Fibrillation; Cardiomyopathy, Hypertrophic; Coronary Artery Bypass; Heart Septum; Humans
PubMed: 33041063
DOI: 10.1016/j.jtcvs.2020.09.035 -
The Journal of Thoracic and... May 2020
Topics: Extracorporeal Membrane Oxygenation; Heart Septal Defects, Ventricular; Heart Ventricles; Hematoma; Humans; Ventricular Septum
PubMed: 32081414
DOI: 10.1016/j.jtcvs.2019.10.026 -
Trends in Cardiovascular Medicine Feb 2020Cardiac resynchronization therapy (CRT) has been a major step in the treatment of heart failure patients and intraventricular conduction delay. As a considerable number... (Review)
Review
Cardiac resynchronization therapy (CRT) has been a major step in the treatment of heart failure patients and intraventricular conduction delay. As a considerable number of patients do not respond adequately to CRT, echocardiographic dyssynchrony selection criteria have been proposed to improve CRT response, but these parameters eventually failed to provide superior selection of CRT candidates. In the last decade, an echo-dyssynchrony parameter called "septal flash" was been reported by several investigators and opinion leaders in the field of CRT. This parameter has a strong pathophysiological rationale and was shown to be a robust and predominant predictor of CRT response in recent observational and retrospective studies. We here provide a comprehensive and balanced overview of septal flash and address several important aspects, questions and potential future implications of septal flash in cardiomyopathy and CRT.
Topics: Action Potentials; Animals; Bundle-Branch Block; Cardiac Resynchronization Therapy; Cardiac Resynchronization Therapy Devices; Clinical Decision-Making; Heart Failure; Heart Rate; Heart Septum; Humans; Recovery of Function; Treatment Outcome; Ventricular Dysfunction, Left; Ventricular Function, Left; Ventricular Remodeling
PubMed: 31000325
DOI: 10.1016/j.tcm.2019.03.008