Intermittent Left Bundle Branch Block Research Articles

LIDOCAINE-INDUCED INTERMITTENT LEFT BUNDLE BRANCH BLOCK AND CHATTERJEE PHENOMENON

TOPIC: Cardiovascular Disease TYPE: Medical Student/Resident Case Reports INTRODUCTION: The frequency of new onset left bundle branch block (LBBB) during anaesthesia and surgery is rare. The most common causes for LBBB are structural heart diseases, acute myocardial infarction, dilated cardiomyopathy, heart failure, and exercise-induced LBBB[1]. We present a rare case of Lidocaine-induced Intermittent Left Bundle Branch Block. CASE PRESENTATION: A 63-year-old female with no medical history had hysterectomy/high uterosacral ligament suspension as an elective procedure for uterine prolapse. The baseline EKG was normal. She went to the operating room as scheduled, but after the injection of 100 mg local Lidocaine, she developed a LBBB on the EKG with ST-T changes (Figure-1). The surgery was aborted, and cardiology was consulted Cardiac enzymes were normal. Upon evaluation by the cardiology team, the patient had no particular complaints, and soon her LBBB had resolved spontaneously without any intervention. A follow-up EKG done a few hours later showed normal sinus rhythm with evidence of T-wave inversion suggestive of cardiac memory or "Chatterjee's phenomenon" (Figure-2). Echocardiogram and Nuclear stress testing were performed, and which were negative for ischemic changes. DISCUSSION: There have been several reports of adverse effects of lidocaine on cardiac conduction after standard doses of intravenous lidocaine. These have included the appearance of type II second-degree heart block, asystole, and complete heart block in an infant. One of the first cases of transient LBBB induced by lidocaine was reported back in 1989 by Tagliente et al[2]. It is not understood how lidocaine may induce a transient LBBB; however, the literature has suggested that lidocaine in high doses can cause a conduction delay within the Purkinje system and subsequently leading to a conduction block. Cardiac memory, or Chatterjee's phenomenon, first described in 1969 by Kanu Chatterjee et al., is defined as a deep inversion of T-wave with ST depression in the un-paced heart following ventricular pacing[3]. It has also been described to occur in other patients with abnormal electricity, including those with intermittent LBBB, WPW, and episodic tachycardia. CONCLUSIONS: On rare occasions, Lidocaine can induce intermittent left bundle branch block. REFERENCE #1: Sarter BH, Hook BG, Callans DJ, Marchlinski FE. Effect of bundle branch block on local electrogram morphologic features: implications for arrhythmia diagnosis by stored electrogram analysis. American heart journal. 1996;131(5):947-52. REFERENCE #2: Tagliente TM, Jayagopal S. Transient left bundle branch block following lidocaine. Anesthesia & Analgesia. 1989;69(4):545-7. REFERENCE #3: Chatterjee K, Harris A, Davies G, Leatham A. Electrocardiographic changes subsequent to artificial ventricular depolarization. British heart journal. 1969;31(6):770 DISCLOSURES: No relevant relationships by Mostafa Abohelwa, source=Web Response No relevant relationships by Monica Botros, source=Web Response No relevant relationships by Zeyad Elharabi, source=Web Response No relevant relationships by Mohamed Elmassry, source=Web Response No relevant relationships by Peter Khalil, source=Web Response No relevant relationships by Sima Shahbandar, source=Web Response No relevant relationships by Victor Test, source=Web Response

The Efficacy and Medium to Long-Term Follow-Up of Transcatheter Retrograde Closure of Perimembranous Ventricular Septal Defects via the Femoral Artery With Amplatzer Duct Occluder II in Children.

Objective: The aim of this study was to assess the efficacy and safety of transcatheter retrograde closure of perimembranous ventricular septal defect (pmVSD) via the femoral artery with an Amplatzer Duct Occluder II (ADO II) in children.Methods: The clinical and follow-up data of 102 children who had successfully undergone transcatheter retrograde closure of pmVSD via the femoral artery with Amplatzer Duct Occluder II (ADO II) from February 2012 to June 2019 in our center were retrospectively reviewed.Results: In 102 of 103 patients, the defects were successfully closed (99.0%). The average age was 4.03 ± 1.84 years and the mean weight was 17.50 ± 5.58 kg. The mean diameter of the defects was 2.58 ± 0.63 mm. Hundred of the occluders had a waist length of 4 mm. The complete closure rate was 89.2% 24 h after the procedure and 98% at the last follow-up. The follow-up period ranged from 6 to 92 months, with a median of 36 months. One child developed new mild aortic regurgitation (AR), and 9 patients developed new mild tricuspid regurgitation (TR). During follow-up, TR disappeared in 5 patients and decreased in 4 patients, and AR relieved in one patient. One patient developed intermittent complete left bundle branch block 4 days after the procedure and recovered sinus rhythm 2 days later. No serious complications occurred.Conclusion: Transcatheter retrograde closure of pmVSD via the femoral artery with ADO II in children is safe, feasible, and effective in selected patients.

A case report of a rare cardiac complication in novel coronavirus disease

BackgroundSince late 2019, the outbreak of COVID-19 has rapidly spread worldwide. As it is a newly emerged disease, many of its manifestations and complications are unknown to us. Cardiac involvement and arrhythmias are another aspect of the disease about which very little is known.Case summaryA 71-year-old male patient presented at the Emergency Department complaining of fever, a dry cough, and dyspneoa. He was admitted due to these symptoms suggestive of COVID-19, and a chest CT and PCR test confirmed the diagnosis. During admission, cardiac involvement was detected, i.e. second-degree atrioventricular block with intermittent left bundle branch block (LBBB) which progressed to fixed LBBB and eventually developed into atrial fibrillation/flutter with bradycardia. Both cardiac troponin and echocardiographic findings for detecting myocarditis were negative. We waited 14 days for resolution of atrioventricular block before permanent pacemaker implantation, but the condition still did not improve after the waiting period.DiscussionCOVID-19 is mainly a respiratory infection but cardiac involvement is not uncommon in the course of the disease. Arrhythmia, during this infection, seems to be caused by an inflammatory response in the myocardium, electrolyte disturbances, and hypoxia; the course of the disease in our case study shows that the virus can preferentially and irreversibly involve the cardiac conduction system.

Real-time validation of the Sgarbossa and modified Sgarbossa criteria in intermittent left bundle branch block

The modified Sgarbossa criteria have been established to aid in the diagnosis of ST-elevation myocardial infarction in patients with left bundle branch block. Thus far, the sensitivities and specificities of the Sgarbossa signs have only been evaluated retrospectively in cohorts of patients with and without occlusive myocardial infarctions. These statistical analyses were based on correlating ST abnormalities with serum markers of myocardial injury and/or results of emergent cardiac catheterization. We present a patient with acute cardiovascular emergency where electrocardiograms revealed intermittent left bundle branch block. In serial ECGs, highly dynamic ST abnormalities on the narrow QRS beats were associated with similarly dynamic ST changes in the left bundle branch block beats. Our findings provided direct and real-time confirmation of the usefulness of the Sgarbossa and the modified Sgarbossa criteria in the diagnosis of acute ST elevation in patients with left bundle branch block.

Worth Remembering: Cardiac Memory Presenting as Deep Anterior T-Wave Inversions Explained by Intermittent Left Bundle Branch Block

Cardiac memory is a common cause of deep T-wave inversions (TWI) in the anterior precordial leads and can be difficult to distinguish from alternative causes of TWI such as myocardial ischemia. Cardiac memory is generally a benign condition except in the setting of prolonged QT when it can contribute to the precipitation of torsades de pointes. Herein, we describe the presentation and clinical course of a case of cardiac memory due to intermittent left bundle branch block (LBBB) that presented asymptomatically to our outpatient cardiology clinic with deep anterior TWI. We discuss common causes of and mechanisms underlying cardiac memory and how to distinguish it from alternative causes of TWI based on 12-lead electrocardiogram. In conclusion, intermittent LBBB is an under-recognized cause of cardiac memory that can present as deep anterior TWI mimicking cardiac ischemia, and awareness of this clinical entity may help prevent unnecessary invasive and expensive testing on otherwise healthy patients.

Expanding benefits from cardiac resynchronization therapy to exercise‐induced left bundle branch block in advanced heart failure

Indications of cardiac resynchronization therapy (CRT) do not include exercise‐induced left bundle branch block, but functional impairment could be improved with CRT in such cases. A 57‐year‐old woman with idiopathic dilated cardiomyopathy (ejection fraction 23%) presented with New York Heart Association Class IV and recurrent hospitalizations. During heart transplant evaluation, a new onset of intermittent left bundle branch block was observed on the cardiopulmonary exercise test. CRT was implanted, and 97% resynchronization rate was achieved. In 12 month follow‐up, both clinical and prognostic exercise parameters improved. In patients with heart failure with reduced ejection fraction and no left bundle branch block at rest, exercise test can uncover electromechanical dyssynchrony that may benefit from CRT.

Pułapka diagnostyczna — dławica piersiowa i intermitujący blok lewej odnogi pęczka Hisa u 68-letniej kobiety z zatorowością płucną. Opis przypadku z obserwacją po roku

In the present communication, a case of a 68 year-old woman consulted at a cardiology service due to angina pectoris is reported. The electrocardiogram (ECG) showed intermittent left bundle branch block. Transthoracic echocardiography revealed signs of pulmonary embolism. The diagnosis was confirmed by computed tomography angiography. The presented case highlights the role of echocardiography in the differential diagnosis of anginal pain and shows that making a correct diagnosis based on ECG may sometimes be challenging.

Expanding Benefits from Cardiac Resynchronization Therapy to Exercise-Induced Left Bundle Branch Block in the Setting of Advanced Heart Failure: A Case Report

Introduction Exercise-induced left bundle branch block (LBBB) is rarely observed in exercise testing, and usually implies a worse prognosis. Cardiac resynchronization therapy (CRT) is well validated in patients with heart failure with reduced ejection fraction (HFrEF) and LBBB. Although the indications of CRT do not include exercise-induced LBBB, the functional impairment secondary to dynamic electromechanical dyssynchrony could potentially be improved with CRT. Case Report A 57-year-old woman with long-standing idiopathic dilated cardiomyopathy (ejection fraction of 23%) presented with clinical deterioration to NYHA functional class 4 and recurrent hospitalizations despite optimal medical treatment. During evaluation for cardiac transplant, new-onset of intermittent LBBB was observed on the cardiopulmonary exercise test (her resting QRS duration was 100ms). A stress echocardiography showed exertion-induced intraventricular and interventricular dyssynchrony. Cardiac resynchronization therapy was then indicated, and 97% resynchronization rate was obtained. There was clinical improvement to NYHA class 2 and no hospitalizations since the CRT initiation. Functional reassessment at 6 and 12 months post-implant demonstrated significant improvement in prognostic exercise parameters (Figure). She currently remains off the transplant list. Summary In HFrEF patients with no LBBB at rest, exercise test and stress echocardiography may uncover dynamic electromechanical dyssynchrony that may benefit from CRT. This is the first report of CRT for treatment of an advanced heart failure patient with worsening symptoms attributed to exercise-induced LBBB.

Determination of the QT Interval in Left Bundle Branch Block: Development of a Novel Formula

BackgroundDetermination of the prolonged QT interval in left bundle branch block (LBBB), which should be of special concern to identify individuals at high risk of potentially fatal cardiac arrhythmia risk, has been problematic. MethodsElectrocardiograms (ECGs) (n = 17) in intermittent LBBB were used to develop a new formula for the calculation of QTc in LBBB. This formula and 5 others were compared in a population with LBBB (n = 2610). The QT was corrected for heart rate (HR) using the Bazett formula (QTcBZT) and the spline QT formula (QTcRBK), which is relatively independent of HR. The JT interval was significantly related to HR. ResultsThe new approach (QTcLBBBNEW = 0.945*QTcRBKLBBB − 26) in LBBB showed the highest correlation with intrinsic QTc (without LBBB) and had minimal HR dependency. Previous formulae to determine the QT interval in LBBB showed significant HR dependency except for one proposed by Rautaharju et al. Inclusion of an HR correction factor in existing formulae blunted HR dependency but not if the QT interval was adjusted by the QTcBZT. In men and women, use of the QTcBZT markedly increases the proportion of individuals with prolonged QTc, which was more evident with increasing HR. The 99th and 97.5th percentiles for QTcLBBBNEW for men and women identified abnormal QT prolongation in LBBB. ConclusionsA new formula that modifies the QT and JT intervals in LBBB predicts the QT interval in the absence of LBBB. Abnormal QT intervals in the 99th and 97.5th percentiles can identify patients with LBBB who have QT interval prolongation.

Intermittent Left Bundle Branch Block – A Challenging Case of Rare Electrocardiogram Phenomenon

We aim to present this rare phenomenon of intermittent left bundle branch block (LBBB) in a patient with aspergillus endocarditis, as a case for arrhythmia round. Intermittent LBBB is an unusual phenomenon. Though first described over six decades ago, only a few cases have been reported and pathophysiological basis remains unknown.

The Heart Remembers: Anterior T wave inversions in a Patient with Intermittent Left Bundle Branch Block

The Heart Remembers: Anterior T wave inversions in a Patient with Intermittent Left Bundle Branch Block

A New Formula for Estimating the True QT Interval in Left Bundle Branch Block.

QT prolongation is an independent risk factor for cardiac mortality. Left bundle branch block (LBBB) is more common in patients as they age. Widening of the QRS in LBBB causes false QT prolongation and thus makes true QT assessment difficult. We aimed to develop a simple formula to achieve a good estimate of the QT interval in the presence of LBBB. To determine the effect of QRS duration on the QT interval, QRS and QT were measured in sinus rhythm and during right ventricular apical pacing in 62 patients (age 55 ± 11 years, 60% male) undergoing electrophysiology studies. A QT formula for LBBB (QT-LBBB) was derived based on the effect of increased QRSLBBB on QTLBBB . The predictive accuracy of the QT-LBBB formula was then tested in 22 patients (age 66 ± 13 years, 64% male) with intermittent LBBB with comparisons to prior QT formulae and JT index. On average, the net increase in QRSLBBB constituted 92% of the net increase in QTLBBB . A new formula, QT-LBBB = QTLBBB - (0.86 * QRSLBBB - 71), which takes the net increase in QRSLBBB into account, best predicted the QT interval with heart rate corrected QTc in the test set of LBBB ECGs when compared to the baseline value and prior formulae. The QT-LBBB formula developed in this study best estimates the true QT interval in the presence of LBBB. It is simple and therefore can be easily utilized in clinical practice.

Cardiac Memory, an Underdiagnosed Condition

Introduction Cardiac memory, also termed Chatterjee phenomenon, is a known yet uncommonly recognized entity in which myocardial repolarization is altered after abnormal ventricular activation, such as with artificial pacemakers, intermittent left bundle branch block, ventricular premature beats, ventricular pre-excitation or episodes of tachycardia. This phenomenon is characterized by persistent but reversible T-wave changes on surface electrocardiogram (ECG) induced by an abnormal electrical activation pattern. The extent and direction of T-wave deviation depend on the duration and direction of abnormal electrical [...]

Intermittent Left Bundle Branch Block: What is the Mechanism?

Intermittent Left Bundle Branch Block: What is the Mechanism?

Repeat the Electrocardiogram!

A 71-year-old diabetic woman with intermittent chest pain and left bundle branch block was admitted to the hospital for further assessment. A repeat electrocardiogram showed new anterior T-wave inversions concordant with the QRS complexes. Thus, she had myocardial ischemia, and coronary arteriography revealed left main and triple vessel coronary disease. She went for urgent coronary artery bypass operation.

A new experimentally validated formula to calculate the QT interval in the presence of left bundle branch block holds true in the clinical setting

The evaluation of the QT interval in the presence of left bundle branch block (LBBB) is associated with the challenge to discriminate native QT interval from the prolongation due to the increase in QRS duration. The newest formula to evaluate QT interval in the presence of LBBB suggests: modified QT during LBBB = measured QT interval minus 50% of LBBB duration. The purpose of this study is therefore to validate the abovementioned formula in the clinical setting. Validation in two separate groups of patients: Patients who alternated between narrow QRS and intermittent LBBB and patients with narrow QRS who developed LBBB after transcatheter aortic valve implantation (TAVI). The acquired mean native QTc intervals and those calculated by the presented formula displayed no significant differences (p>.99 and p>.75). In this study we proved for the first time the validity and applicability of the experimentally acquired formula for the evaluation of the QT interval in the presence of LBBB in a clinical setting.

Episodic Left Bundle Branch Block-A Comprehensive Review of the Literature.

Episodic (transient/ intermittent) left bundle branch block (LBBB) has been associated with different conditions such as bradycardia, tachycardia, anesthesia, acute pulmonary embolism, changes in intrathoracic pressure, chest trauma, cardiac interventional procedures, mad honey poisoning, and in other clinical settings. Of note, exclusion of an acute coronary syndrome in the setting of episodic LBBB is of great importance. Moreover, episodic LBBB is sometimes symptomatic and may be associated with left ventricular systolic and/or diastolic dysfunction or conduction disturbances leading to syncope. This review article provides a comprehensive overview of the conditions associated with episodic LBBB and discusses the clinical impact of this phenomenon.

Painful left bundle branch block syndrome: Clinical and electrocardiographic features and further directions for evaluation and treatment

Painful left bundle branch block (LBBB) is a rarely diagnosed chest pain syndrome caused by intermittent LBBB in the absence of myocardial ischemia. Its prevalence, mechanism, detailed electrocardiographic (ECG) features, and effective treatments are not well described. The purpose of this study was to characterize clinical and ECG features of patients with painful LBBB syndrome with respect to the LBBB ECG morphology (in particular QRS axis and the precordial S/T wave ratio), clarify diagnostic criteria and possible mechanisms, and provide directions for further evaluation and treatment. We analyzed clinical (n = 50) and ECG (n = 15) features of patients with painful LBBB syndrome (4 patients in our practice and 46 cases identified in the literature). All 15 ECGs of patients with painful LBBB syndrome had an inferior QRS axis and a very low (<1.8) precordial S/T wave ratio, which was consistent with the "new LBBB" pattern. We report a case of painful LBBB syndrome coexisting with coronary artery disease. Right ventricular apical pacing resolved intractable chest pain in 1 case of painful LBBB. Painful LBBB ECG morphology within seconds/minutes of its onset is consistent with the new LBBB pattern with a very low (<1.8) precordial S/T wave ratio and inferior QRS axis. Painful LBBB syndrome can coexist with coronary artery disease, complicating the assessment of chest pain in the setting of LBBB. An electrophysiology study might be considered to investigate whether changing ventricular activation pattern by pacing provides consistent pain control and to select the most effective pacing configuration.

Different ECG manifestations of left ventricular hypertrophy in presence of intermittent LBBB and RBBB

An 86-year-old female with aortic stenosis was qualified for invasive correction of the valvular heart disease. She developed a severe ventricular hypertrophy (LVH) and had an intermittent left bundle branch block (LBBB) and right bundle branch block (RBBB). We report the case of a single electrocardiographic examination showing changes specific for LVH, present in all forms of intraventricular conduction. The case perfectly depicts how the intracardiac vectors of depolarization change due to bundle branch blocks and how it effects QRS complex morphology.

Cardiac memory: diagnostic tool in the making.

Classic definition of the term cardiac memory (CM) refers to the persistent T-wave changes on the ECG after a period of wide QRS rhythms that become evident once normal ventricular activation pattern is restored. It is related to the term ventricular electric remodeling sometimes used in basic science literature. Although CM itself is considered as an adaptive reaction to the change in the ventricular activation sequence, its manifestations (usually T-wave inversions, TWIs) are often confused with pathological conditions manifesting with TWI, such as myocardial ischemia or infarction. Although originally CM was described after restoration of the normal ventricular activation (narrow QRS), recently it was described and studied in wide QRS rhythms significantly expanding the clinical relevance of this phenomenon. Although complex molecular mechanisms of CM have been previously reviewed extensively, practical clinical application of this phenomenon received much less attention. In this article, we will focus on the clinically relevant aspects of CM including its diagnostic use in narrow and wide QRS rhythms. We will also examine how the fundamental CM property of being initiated by the changes in the geometry of the ventricular contraction might open new perspectives in wide QRST morphology analysis by establishing parallels between electric and mechanical functions of the heart. In 1915, White1 was the first to observe the phenomenon of transient TWI after single ventricular premature beats. Later in the 1940s, TWIs after conversion to sinus rhythm were described after paroxysmal tachycardias.2 Since then abnormal T waves of various duration have been documented after intermittent ventricular pre-excitation,3–5 ventricular pacing,6,7 intermittent left bundle branch block (LBBB),8,9 ventricular tachycardia,10 and even QRS widening associated with sodium channel blocker toxicity.11 In 1982, Rosenbaum et al10 introduced the term heart memory and presented the …