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Shinji Kinoshita - One of the best experts on this subject based on the ideXlab platform.

  • Sinus escape-capture Bigeminy alternating with sinus extrasystolic Bigeminy: dual atrial response and apparent sinus escape.
    Journal of cardiovascular medicine (Hagerstown Md.), 2011
    Co-Authors: Shinji Kinoshita, Takakazu Katoh
    Abstract:

    We report here five cases of sinus Bigeminy in which comparatively long PP intervals alternated with comparatively short PP intervals, suggesting 'sinus escape-capture Bigeminy' or 'sinus extrasystolic Bigeminy'. In three of the cases, these two forms of sinus Bigeminy were found in the same patient. This is the first study on 'sinus escape-capture Bigeminy' alternating with 'sinus extrasystolic Bigeminy'. The electrocardiographic findings in these cases suggest the possibility that 'sinus escape' in the sinoatrial junction is not true escape. Attempts are made to explain that apparent sinoatrial junctional escape occurs as a result of markedly slow conduction through the slow sinoatrial pathway, using the concepts of 'dual sinoatrial pathways' and 'double atrial response'.

  • Atrial escape-capture Bigeminy in dominant atrial rhythm with 2:1 exit block
    Journal of electrocardiology, 2003
    Co-Authors: Takakazu Katoh, Shinji Kinoshita, Yoshihiko Sasaki, Ryuzaburou Yasuda, Yoshinori Tsujimura
    Abstract:

    A 27-year-old woman with atrial Bigeminy is reported in whom long PP intervals alternate with short PP intervals. All P waves are negative in lead II and all PR intervals measure 0.12 s. In the 12-lead electrocardiogram, however, these P waves were definitely different in configuration from each other, and were divided into two groups. Namely, these negative P waves are divided into those of dominant atrial rhythm J1 with 2:1 exit block, and those of atrial escape J2. Long J1-J2 intervals alternate with short J2-J1 intervals. These electrocardiographic findings show the presence of atrial escape-capture Bigeminy. Such atrial escape-capture Bigeminy in dominant atrial rhythm with 2:1 exit block has never been reported before.

  • Sinus escape-capture Bigeminy and sinus extrasystolic Bigeminy.
    Journal of electrocardiology, 2000
    Co-Authors: Shinji Kinoshita, Takakazu Katoh, Yoshinori Tsujimura, Yoshihiko Sasaki, Kazushi Kubo, Masahiro Murata, Yohtaro Oyama
    Abstract:

    Abstract Blocking conduction between the sinus node and the atria(SA block) can be responsible for symptomatic rhythm problems. However, in atrial escape-capture Bigeminy with SA block, when atrial escape P waves originate in a site within or close to the sinus node, the diagnosis of SA block is not easy. Electrocardiograms were selected from 7 people with atrial Bigeminy because (1) all atrial deflections (P waves) were almost the same in shape and in length of PR intervals, (2) comparatively long PP intervals alternated with comparatively short PP intervals, and (3) occasionally the atrial Bigeminy changed to normal regular sinus rhythm in which 2 or more sinus P waves were found in succession. An attempt is made to clarify the mechanism for these cases. When regular sinus rhythm changed to bigeminal rhythm, the long PP interval introduced the Bigeminy in 3 cases, indicating the presence of “sinus” escape-capture Bigeminy; whereas the short PP interval introduced the Bigeminy in the other 4 cases, indicating the presence of “sinus” extrasystolic Bigeminy. In cases of sinus escape-capture Bigeminy associated with SA block, the cases may occasionally be diagnosed wrongly as ordinary sinus arrhythmia not associated with SA block. Therefore, it seems that sinus escape-capture Bigeminy is not so rare as is generally believed. Patients with SA block often require implantation of the artificial pacemaker. Thus, the authors believe that differentiation of sinus escape-capture Bigeminy from other forms of “sinus” Bigeminy is clinically important.

  • Mechanism of tachycardia-dependent appearance of ventricular extrasystoles in concealed Bigeminy
    Journal of Electrocardiology, 1996
    Co-Authors: Shinji Kinoshita, Yoshinori Tanabe, Tatsuo Satoh
    Abstract:

    Abstract A case of concealed ventricular Bigeminy is reported in which the number of sinus QRS complexes intervening between two successive noninter-polated extrasystoles was always uneven. Coupling intervals of manifest extrasystoles to the preceding sinus QRS complexes were almost fixed and much longer than sinus QT intervals. Bradycardia-dependent disappearance of manifest Bigeminy and tachycardia-dependent appearance of extrasystoles occurred in this case. Apparently, 2:1 block of sinus impulses occurred in the reentrant pathway, with markedly depressed conductivity. Concealed electrotonic conduction of blocked sinus impulses in the pathway of extrasystoles may have favored the appearance of the subsequent manifest extrasystoles without concealed conduction owing to two-level block. A possible explanation for the mechanism of such concealed Bigeminy is presented, which uses the concepts of longitudinal dissociation and electrotonic inhibition in the reentrant pathway with markedly depressed conductivity.

  • Bradycardia- and tachycardia-dependent termination of ventricular Bigeminy: Mechanism of ventricular extrasystoles with fixed coupling
    American heart journal, 1995
    Co-Authors: Shinji Kinoshita, Go Konishi, Fumihiko Okada, Makoto Kinoshita, Shinsaku Ogawa
    Abstract:

    Fourteen men with intermittent ventricular Bigeminy were selected for this study because coupling intervals of the extrasystoles were considerably long and usually fixed, and bradycardia-dependent (10 cases) and/or tachycardia-dependent (12 cases) termination of Bigeminy occurred. In all cases, when the heart rate ranged between two certain values, ventricular Bigeminy with fixed-coupled extrasystoles was sustained. In all cases showing bradycardia-dependent termination, Bigeminy was suddenly terminated with no changes in coupling of the preceding extrasystoles when the heart rate was decreased below a certain lower value. In all cases showing tachycardia-dependent termination except one, when the heart rate increased beyond a certain higher value, coupling intervals gradually lengthened until Bigeminy was terminated. These findings strongly suggest the possibility that, in a considerably large number of clinical cases, ventricular extrasystoles with fixed coupling are caused by longitudinal dissociation of conduction in the reentrant pathway of extrasystoles.

Fumihiko Okada - One of the best experts on this subject based on the ideXlab platform.

  • Bradycardia- and tachycardia-dependent termination of ventricular Bigeminy: Mechanism of ventricular extrasystoles with fixed coupling
    American heart journal, 1995
    Co-Authors: Shinji Kinoshita, Go Konishi, Fumihiko Okada, Makoto Kinoshita, Shinsaku Ogawa
    Abstract:

    Fourteen men with intermittent ventricular Bigeminy were selected for this study because coupling intervals of the extrasystoles were considerably long and usually fixed, and bradycardia-dependent (10 cases) and/or tachycardia-dependent (12 cases) termination of Bigeminy occurred. In all cases, when the heart rate ranged between two certain values, ventricular Bigeminy with fixed-coupled extrasystoles was sustained. In all cases showing bradycardia-dependent termination, Bigeminy was suddenly terminated with no changes in coupling of the preceding extrasystoles when the heart rate was decreased below a certain lower value. In all cases showing tachycardia-dependent termination except one, when the heart rate increased beyond a certain higher value, coupling intervals gradually lengthened until Bigeminy was terminated. These findings strongly suggest the possibility that, in a considerably large number of clinical cases, ventricular extrasystoles with fixed coupling are caused by longitudinal dissociation of conduction in the reentrant pathway of extrasystoles.

  • Differentiation between parasystole and reentry in concealed Bigeminy.
    Cardiology, 1992
    Co-Authors: Shinji Kinoshita, Go Konishi, Fumihiko Okada
    Abstract:

    There are two different theories to explain the mechanism of concealed Bigeminy: one is '2:1 concealed reentry'; the other is 'irregular parasystole.' Two exemplary cases of the even-number variant of concealed Bigeminy are presented. In case 1, the mechanism can be explained by an irregular parasystole due to a modulated parasystole; however, findings during temporary sinus arrest caused by vagal stimulation indicate that this case is not governed by a parasystole, but by a 2:1 concealed reentry. In case 2, the mechanism can be explained by a 2:1 concealed reentry without parasystole; however, findings during temporary sinus arrest indicate that this case is governed by an irregular parasystole due to a type-I second-degree entrance block. Thus, in cases of concealed Bigeminy without pure ectopic cycles, it does not seem easy to explain the mechanism of concealed Bigeminy on the theory of a modulated parasystole.

Noriaki Ikeda - One of the best experts on this subject based on the ideXlab platform.

  • ectopic cycle length estimation from the quantified distribution patterns of ventricular Bigeminy and trigeminy
    Heart Rhythm O2, 2021
    Co-Authors: Kan Takayanagi, Shiro Nakahara, Yoshihiko Sakai, Yuiti Hori, Isao Taguchi, Noriaki Ikeda
    Abstract:

    Background Ectopic cycle length (ECL) and the distribution patterns of ventricular Bigeminy and trigeminy, expressed as their postextrasystolic intervals (PEIs) and interectopic intervals (IEIs), have been poorly pursued. Objective Based on modulation theory, we hypothesized that the PEIs of Bigeminy and trigeminy determine their IEIs and ECL. Methods Ambulatory electrocardiograms of 1290 patients with ventricular premature complexes (≥3000/day) were studied. To quantify their distribution pattern on the PEI vs IEI curve (PIC), we introduced the following 2 ratios: PEI of trigeminy to PEI of Bigeminy ratio (T/B-PEI) and IEI of trigeminy to IEI of Bigeminy ratio (T/B-IEI). Distribution patterns were divided into 3 types by T/B-PEI: standard type ( 1.20). ECL was defined as the average of the Bigeminy and trigeminy intervals in the standard type, and Bigeminy intervals in the other 2 types. Results T/B-IEI disclosed significant linear relationship with T/B-PEI (P Conclusion We confirmed that T/B-PEI determines T/B-IEI and ECL by discriminating the 3 distribution patterns. Among them, trigeminy PEI/ECL decided the 2 types of modulation by the first sinus QRS, starting at the early delay phase or the later acceleration phase.

  • Ectopic cycle length estimation from the quantified distribution patterns of ventricular Bigeminy and trigeminy
    Heart Rhythm O2, 2021
    Co-Authors: Kan Takayanagi, Shiro Nakahara, Yoshihiko Sakai, Yuiti Hori, Isao Taguchi, Noriaki Ikeda
    Abstract:

    Abstract Background Ectopic cycle length (ECL) and the distribution patterns of ventricular Bigeminy and trigeminy, expressed as their postextrasystolic intervals (PEIs) and interectopic intervals (IEIs), have been poorly pursued. Objective Based on modulation theory, we hypothesized that the PEIs of Bigeminy and trigeminy determine their IEIs and ECL. Methods Ambulatory electrocardiograms of 1,290 patients with ventricular premature complexes(VPCs; ≥ 3,000/day) were studied. To quantify their distribution pattern on the PEI vs. IEI curve (PIC), we introduced the following two ratios; PEI of trigeminy to PEI of Bigeminy ratio (T/B-PEI) and IEI of trigeminy to IEI of Bigeminy ratio (T/B-IEI). Distribution patterns were divided into three types by T/B-PEI: standard type ( 1.20). ECL was defined as the average of the Bigeminy and trigeminy intervals in the standard type, and Bigeminy intervals in the other two types. Results T/B-IEI disclosed significant linear relationship with T/B-PEI (p Conclusion We confirmed that T/B-PEI determines T/B-IEI and ECL by discriminating the three distribution patterns. Among them, trigeminy PEI/ECL decided the two types of modulation by the first sinus QRS, starting at the early delay phase or the later acceleration phase. 242 Words

  • Strong modulation of ectopic focus as a mechanism of repetitive interpolated ventricular Bigeminy with heart rate doubling
    Heart rhythm, 2013
    Co-Authors: Kan Takayanagi, Shiro Nakahara, Noritaka Toratani, Ryuji Chida, Sayuki Kobayashi, Yoshihiko Sakai, Akihiro Takeuchi, Noriaki Ikeda
    Abstract:

    Background Repetitive interpolated ventricular Bigeminy (RIVB) can introduce a doubling of the ventricular rate. Objective To clarify the mechanism of RIVB, we hypothesized that it was introduced by a strong modulation of the ventricular automatic focus. Methods RIVB, defined as more than 7 Bigeminy events, was detected by instantaneous heart rate and Bigeminy interval (BI) tachograms in 1450 successive patients with frequent ventricular premature contractions (≥3000 per day). Postextrasystolic interval Bigeminy interval curves were plotted to determine the degree of modulation. Mean sinus cycle length Bigeminy interval curves were plotted for selection. RIVB was simulated by using a computer-based parasystole model. Results RIVB was observed in 7 patients (age 60 ± 16 years; 2 men and 5 women) with a heart rate of 58.2 ± 6.5 beats/min during a rest period both during the day and at night. The tachograms disclosed the onset of the RIVB with a doubled ventricular rate to 112.3 ± 8.5 beats/min. On the postextrasystolic interval Bigeminy interval curves, compensatory Bigeminy and interpolated Bigeminy constituted overlapping regression lines with slopes close to 1.00 and RIVB was located in the lower left portion. RIVB lasting for up to 3 hours was quickly detected by mean sinus cycle length Bigeminy interval curve. The PQ interval immediately after RIVB was prolonged in comparison with baseline (0.18 ± 0.02 to 0.21 ± 0.02 seconds; P Conclusions Our findings support the hypothesis that RIVB was introduced by strongly modulated ventricular pacemaker accelerated by an intervening normal QRS.

  • Two types of distribution patterns of Bigeminy and trigeminy in long-term ECG: a model-based interpretation
    2008 Computers in Cardiology, 2008
    Co-Authors: Noriaki Ikeda, Akihiro Takeuchi, K. Takayanagi, Noritaka Mamorita, H. Miyahara
    Abstract:

    Two types of distribution patterns of Bigeminy and trigeminy are found in analysis of long-term ECG. To investigate the mechanism underlying this finding, a simplified equation of a modulated parasystole model was used and symbolic solutions for cyclic VPC patterns were obtained. The map of these solutions in a model parameter plane showed two different solutions for Bigeminy, four kinds of trigeminy, two kinds of quadrigeminy, combinations of these patterns, and apparently normal ECG. These results are used to explain the features of the distribution patterns.

Shinsaku Ogawa - One of the best experts on this subject based on the ideXlab platform.

  • Bradycardia- and tachycardia-dependent termination of ventricular Bigeminy: Mechanism of ventricular extrasystoles with fixed coupling
    American heart journal, 1995
    Co-Authors: Shinji Kinoshita, Go Konishi, Fumihiko Okada, Makoto Kinoshita, Shinsaku Ogawa
    Abstract:

    Fourteen men with intermittent ventricular Bigeminy were selected for this study because coupling intervals of the extrasystoles were considerably long and usually fixed, and bradycardia-dependent (10 cases) and/or tachycardia-dependent (12 cases) termination of Bigeminy occurred. In all cases, when the heart rate ranged between two certain values, ventricular Bigeminy with fixed-coupled extrasystoles was sustained. In all cases showing bradycardia-dependent termination, Bigeminy was suddenly terminated with no changes in coupling of the preceding extrasystoles when the heart rate was decreased below a certain lower value. In all cases showing tachycardia-dependent termination except one, when the heart rate increased beyond a certain higher value, coupling intervals gradually lengthened until Bigeminy was terminated. These findings strongly suggest the possibility that, in a considerably large number of clinical cases, ventricular extrasystoles with fixed coupling are caused by longitudinal dissociation of conduction in the reentrant pathway of extrasystoles.

Claudia Lerma - One of the best experts on this subject based on the ideXlab platform.

  • mutual information analysis reveals Bigeminy patterns in andersen tawil syndrome and in subjects with a history of sudden cardiac death
    Physica A-statistical Mechanics and Its Applications, 2012
    Co-Authors: Elisa Nunezacosta, Claudia Lerma, Manlio F Marquez, Marco V Jose
    Abstract:

    Herein we introduce the Mutual Information Function (MIF) as a mathematical method to analyze ventricular Bigeminy in certain pathological conditions of the heart known to be associated with frequent ventricular arrhythmias. In particular, we show that the MIF is sensitive enough to detect the Bigeminy pattern in symbolic series from patients with Andersen–Tawil syndrome as well as in a group of patients from the Sudden Cardiac Death Holter Databases. The results confirm that MIF is an adequate method to detect the autocorrelation between the appearance of sinus and ventricular premature beats resulting in a Bigeminy pattern. It is also shown that MIF reflects the Bigeminy patterns as a function of the percentage of ventricular premature beats present in the symbolic series and also as a function of the percentage of Bigeminy. The MIF was also useful to establish a consistent difference in the Bigeminy pattern related to the diurnal and nocturnal periods presumably associated to the circadian rhythm of the heart. Understanding of the ventricular Bigeminy patterns throughout 24-hours could provide some insights into the pathogenesis of ventricular tachyarrhythmias in these pathological conditions.

  • Mutual information analysis reveals Bigeminy patterns in Andersen–Tawil syndrome and in subjects with a history of sudden cardiac death
    Physica A: Statistical Mechanics and its Applications, 2012
    Co-Authors: Elisa Núñez-acosta, Claudia Lerma, Manlio F Marquez, Marco V Jose
    Abstract:

    Abstract Herein we introduce the Mutual Information Function (MIF) as a mathematical method to analyze ventricular Bigeminy in certain pathological conditions of the heart known to be associated with frequent ventricular arrhythmias. In particular, we show that the MIF is sensitive enough to detect the Bigeminy pattern in symbolic series from patients with Andersen–Tawil syndrome as well as in a group of patients from the Sudden Cardiac Death Holter Databases. The results confirm that MIF is an adequate method to detect the autocorrelation between the appearance of sinus and ventricular premature beats resulting in a Bigeminy pattern. It is also shown that MIF reflects the Bigeminy patterns as a function of the percentage of ventricular premature beats present in the symbolic series and also as a function of the percentage of Bigeminy. The MIF was also useful to establish a consistent difference in the Bigeminy pattern related to the diurnal and nocturnal periods presumably associated to the circadian rhythm of the heart. Understanding of the ventricular Bigeminy patterns throughout 24-hours could provide some insights into the pathogenesis of ventricular tachyarrhythmias in these pathological conditions.

  • The rule of Bigeminy revisited: analysis in sudden cardiac death syndrome.
    Journal of electrocardiology, 2006
    Co-Authors: Claudia Lerma, Chiu Fan Lee, Leon Glass, Ary L. Goldberger
    Abstract:

    Background: The rule of Bigeminy is commonly explained by a reentrant mechanism. We hypothesize that in patients with prolonged ventricular repolarization, the rule of Bigeminy may be caused by premature ventricular complexes (PVCs) due to early afterdepolarizations. We evaluated these ventricular arrhythmias over extended periods in patients with sudden cardiac death syndrome. Methods: The electrocardiographic (ECG) characteristics of 15 recordings from the PhysioNet Sudden Cardiac Death Holter Database were analyzed for the persistence of Bigeminy, interaction between the underlying cardiac rhythm and the coupling interval, and influence of a prolonged initiating RR cycle on the self-perpetuation of the arrhythmias. Results: Eight (53%) patients had classic torsade de pointes (TdP), 5 (33%) had other polymorphic ventricular tachycardia (VT), and 2 (13%) had monomorphic VT. Group A, which comprised 6 of the patients with TdP, had the following ECG tetrad: (1) frequent ventricular Bigeminy (N5% of total ventricular arrhythmias), (2) long corrected QT interval (N0.5 second), (3) relatively fixed coupling interval, and (4) onset of Bigeminy (n = 4) and TdP (n = 6) after a short-long RR sequence. Patients in group A had slower heart rates (mean RR = 1.12 F 0.26 vs 0.77 F 0.13 seconds, P b .01), longer QT intervals (corrected QT = 0.57 F 0.06 vs 0.45 F 0.06 second; P b .01) and more cases with prominent U waves (83% vs 33%, P b .05) than patients in group B (n = 9), composed of patients who had other types of VT, or TdP without frequent Bigeminy. Conclusions: We identified a set of ECG characteristics that supports the notion that premature ventricular complexes during self-perpetuating ventricular Bigeminy (brule of BigeminyQ) in long QT syndromes may be due to early afterdepolarizations.

  • The rule of Bigeminy revisited: A possible marker of triggered activity preceding torsade de pointes
    Heart Rhythm, 2005
    Co-Authors: Claudia Lerma, Chiu Fan Lee, Ary L. Goldberger, Leon Glass
    Abstract:

    Torsade de pointes (TdP), a form of polymorphic ventricular tachycardia that can lead to sudden cardiac death, is associated with prolongation of repolarization which induces premature ventricular complexes due to early afterdepolarizations (EADs). We hypothesized that analysis of long-term recordings from the open-access Sudden Cardiac Death Holter Database (www.physionet.org) might identify electrocardiographic characteristics that are predictors of TdP. Out of the 23 patients in this database, 14 patients had TdP. These records were analyzed to identify properties of the arrhythmias including the coupling interval and the presence of characteristic arrhythmias such as ventricular Bigeminy, or trigeminy. We identified a subgroup of 6 patients (5 females and 1 male, ages 30-89 years, 4 with sinus rhythm and 2 with atrial fibrillation), who displayed the following triad: i) fixed coupling intervals of ventricular ectopic beats to preceding QRS complexes; ii) frequent ventricular Bigeminy; and iii) onset of Bigeminy following an abnormally long RR interval. Furthermore, the mean corrected QT interval was greater than 0.44s immediately before the onset of Bigeminy in all patients. Pick and Langendorf observed that ventricular Bigeminy tends to perpetuate itself —“the rule of Bigeminy”— and suggested two possible mechanisms, reentry and parasystole. Subsequently, Cranefield suggested that bigeminal rhythms could be due to EADs, where the long compensatory pause following an ectopic beat would predispose towards an EAD which would perpetuate the rhythm. In this subset of patients, our findings are most consistent with the EAD-related mechanism and suggest an electrocardiographic triad of risk for TdP to be tested in larger databases.