Fascicular Block Research Articles

Unveiling cardiac amyloidosis, its characteristics and outcomes among patients with mitral regurgitation undergoing transcatheter edge-to-edge mitral valve repair

Abstract Background Mitral regurgitation (MR) and cardiac amyloidosis (CA) both primarily affect older patients. Data on co-existence and prognostic implications of MR and CA are currently lacking. Purpose We aimed to identify prevalence, clinical characteristics and outcomes of MR-CA compared to lone MR. Methods Consecutive patients undergoing transcatheter edge-to-edge repair (TEER) for MR were screened for concomitant CA at two Austrian centers using a multi-parametric approach including core-lab 99mTc-DPD bone scintigraphy and echocardiography, and immunoglobulin light-chain assessment. Transthyretin-CA (ATTR) was diagnosed by DPD (Perugini Grade-1: early infiltration; Grades-2/3: clinical CA) and absence of monoclonal protein, and light-chain-(AL)-CA via tissue biopsy. Mass spectroscopy was performed in case of conflicting immunohistochemical results. All-cause mortality and hospitalization for heart failure (HHF) served as composite endpoint. Results In total, 120 patients (76.9±8.1 years, 55.8% male) were recruited. Clinical CA was diagnosed in n=14 (11.7%; 12 ATTR, 1 AL, 1 combined ATTR/AL), and early amyloid infiltration in n=9 (7.5%). MR-CA had higher troponin levels, thicker left ventricular walls, and a higher prevalence of carpal tunnel syndrome and left anterior fascicular block compared to lone MR (all p<0.05). Independent predictors of MR-CA were increased posterior wall thickness, and presence of left anterior fascicular block on ECG. Procedural success (MR reduction ≥1 grade) and periprocedural complications of TEER were similar in MR-CA and lone MR (p for all=n.s.). After a median of 1.7 years, 25.8% had experienced death and/or HHF. MR-CA had worse outcomes compared to lone MR with regard to the composite endpoint (HR 2.2, 95% confidence interval [95% CI] 1.0–4.7, p=0.039), driven by a 2.5-fold higher risk for HHF (HR 2.5, 95% CI 1.1–5.9), but comparable mortality (HR 1.6, 95% CI 0.4–6.1; Graphical abstract). Conclusions Dual pathology of MR-CA is common in elderly MR patients undergoing TEER, and has worse post-interventional outcomes compared to lone MR. Given technical feasibility of TEER in MR-CA, valvular repair should be considered as an option to improve forward volume in a state with typically low output. Future studies should evaluate the prognostic benefits of TEER and CA-specific treatment in MR-CA. Funding Acknowledgement Type of funding sources: None.

Impact of bundle branch block morphology on outcomes of patients with syncope and bifascicular block: A SPRITELY (POST 3) substudy

Permanent pacing is often considered for patients with syncope and bifascicular block. The purpose of this study was to determine whether QRS morphology or other electrocardiographic characteristics can identify patients who may benefit from permanent pacing. The Syncope: Pacing or Recording in the Later Years (SPRITELY) trial was a multicenter trial that randomized patients with bifascicular block and syncope (n = 115) to empiric pacemaker implantation vs implantable loop recorder (ILR) monitoring. In this SPRITELY subanalysis, baseline 12-lead electrocardiograms were evaluated for bundle branch block (BBB) morphology, QRS width, and PR and QT intervals and their impact on clinical outcomes was assessed. There were 41 patients with left BBB (36%), 69 patients with right bundle branch block (RBBB) and left anterior fascicular block (60%), and 5 patients with RBBB and left posterior fascicular block (4%). Pacemaker implant compared with ILR was associated with a significant reduction of major study-related events (MSREs) in both patients with left BBB (23.8% vs 78.9%; P = .001) and those with RBBB (27% vs 72.9%; P < .0001). Similarly, a reduction of MSREs was observed in both patients with trifascicular block (23% vs 84.6%; P < .0001) and those with bifascicular block (26.6% vs 68.9%; P = .002). In the group randomized to ILR monitoring, the type of BBB was not a predictor of recurrent syncope (P = .30), bradycardia requiring pacemaker (P = .15), or MSREs (P = .42). The presence ofPR interval prolongation or QRS width in this group did not predict MSREs (P = .22 and P = .96, respectively). In patients with syncope and bifascicular block, pacemaker implantation reduces adverse events as compared with ILR monitoring, irrespective of the type of BBB or the presence of PR interval prolongation.

Chagas’ disease: the hidden enemy around the world

Trypanosoma cruzi (T. cruzi) infection is endemic in Latin America.1 T. cruzi can be transmitted to human beings through the feces of a kissing bug, congenitally, blood transfusion, oral transmission, laboratory contamination, and organ transplantation.1 In 14–30% of patients, acute T. cruzi infection is followed by a long, clinically silent period before the clinical presentation of chronic Chagas’ disease (CD). The T. cruzi infection may result in heterogeneous heart (H) phenotypes, including bradycardia; right bundle-branch block, left anterior fascicular block; cardiomyopathy; heart failure (HF), thromboembolism; arrhythmias; sudden death; and syncope.

Inflammatory infiltration of the cardiac conduction system in acute lymphocytic myocarditis.

A 53-year-old man with prior history of bone marrow transplant after acute myeloblastic leukaemia was admitted in the acute cardiac care unit due to suspected acute myocarditis. At admission, his electrocardiogram (ECG) showed right bundle branch block and left anterior fascicular block (Panel A). Previously, he had been assessed regularly in a dedicated cardio-oncology clinic, with normal ECG and transthoracic echocardiography (see Supplementary material online, Videos S1 and S2). Despite high-dose pulses of methylprednisolone, he developed both complete atrio-ventricular (AV) block and progressive left ventricular systolic dysfunction (see Supplementary material online, Videos S3 and S4), leading to cardiogenic shock requiring temporary transvenous pacing and mechanical circulatory support with VA-ECMO. However, he died on day 9 due to multiorgan failure. Gross examination of the heart (Panel B) was normal, but histopathology and immunohistochemistry showed significant infiltration of the ventricular myocardium (Panel C), AV node (Panel D) left anterior fascicle (Panel E), and right bundle branch (Panel F) by mononuclear CD3 + T cells, consistent with the diagnosis of lymphocytic myocarditis. High-definition images S1-S8 are included in the Supplementary material online.

Comparison between conduction system pacing and cardiac resynchronization therapy in right bundle branch block patients.

A significant number of right bundle branch block (RBBB) patients receive cardiac resynchronization therapy (CRT), despite lack of evidence for benefit in this patient group. His bundle (HBP) and left bundle pacing (LBP) are novel CRT delivery methods, but their effect on RBBB remains understudied. We aim to compare pacing-induced electrical synchrony during conventional CRT, HBP, and LBP in RBBB patients with different conduction disturbances, and to investigate whether alternative ways of delivering LBP improve response to pacing. We simulated ventricular activation on twenty-four four-chamber heart geometries each including a His-Purkinje system with proximal right bundle branch block (RBBB). We simulated RBBB combined with left anterior and posterior fascicular blocks (LAFB and LPFB). Additionally, RBBB was simulated in the presence of slow conduction velocity (CV) in the myocardium, left ventricular (LV) or right ventricular (RV) His-Purkinje system, and whole His-Purkinje system. Electrical synchrony was measured by the shortest interval to activate 90% of the ventricles (BIVAT-90). Compared to baseline, HBP significantly improved activation times for RBBB alone (BIVAT-90: 66.9 ± 5.5 ms vs. 42.6 ± 3.8 ms, p < 0.01), with LAFB (69.5 ± 5.0 ms vs. 58.1 ± 6.2 ms, p < 0.01), with LPFB (81.8 ± 6.6 ms vs. 62.9 ± 6.2 ms, p < 0.01), with slow myocardial CV (119.4 ± 11.4 ms vs. 97.2 ± 10.0 ms, p < 0.01) or slow CV in the whole His-Purkinje system (102.3 ± 7.0 ms vs. 75.5 ± 5.2 ms, p < 0.01). LBP was only effective in RBBB cases if combined with anodal capture of the RV septum myocardium (BIVAT-90: 66.9 ± 5.5 ms vs. 48.2 ± 5.2 ms, p < 0.01). CRT significantly reduced activation times in RBBB in the presence of severely slow RV His-Purkinje CV (95.1 ± 7.9 ms vs. 84.3 ± 9.3 ms, p < 0.01) and LPFB (81.8 ± 6.6 ms vs. CRT: 72.9 ± 8.6 ms, p < 0.01). Both CRT and HBP were ineffective with severely slow CV in the LV His-Purkinje system. HBP is effective in RBBB patients with otherwise healthy myocardium and Purkinje system, while CRT and LBP are ineffective. Response to LBP improves when LBP is combined with RV septum anodal capture. CRT is better than HBP only in patients with severely slow CV in the RV His-Purkinje system, while CV slowing of the whole His-Purkinje system and the myocardium favor HBP over CRT.

Prevalence and incidence of intraventricular conduction disturbances among Chinese adults: Results from the Kailuan study.

ObjectivesEpidemiological data on intraventricular conduction disturbances (IVCDs) are limited in the Chinese population. We aimed to investigate the prevalence and incidence of different types of IVCDs among Chinese adults.MethodsFrom June 2006 to October 2007, a total of 100,250 individuals from the Kailuan Study underwent electrocardiogram examinations. Follow-up visits were performed biennially. The prevalence and incidence of right bundle branch block (RBBB), incomplete RBBB (IRBBB), left bundle branch block (LBBB), incomplete LBBB, left anterior fascicular block (LAFB), left posterior fascicular block (LPFB) and non-specific IVCD (NIVCD) were calculated. Their association with risk factors and cardiovascular diseases was also investigated.ResultsThe prevalence and incidence of all IVCDs were 3.19 and 1.70%, respectively. RBBB, IRBBB, and LAFB were the IVCD types that had the highest prevalence and incidence. The prevalence (3.67% vs. 1.29%; P < 0.001) and incidence (1.93% vs. 0.84%; P < 0.001) of IVCDs were higher among males than among females. The prevalence and incidence of most IVCD types increased with age. IRBBB, LBBB, and LAFB were significantly associated with hypertension. LBBB and NIVCD were associated with diabetes mellitus. In addition, LBBB and LAFB were related to prior myocardial infarction.ConclusionIVCDs differ in prevalence and incidence according to sex and age group. They also show disparate associations with other cardiovascular comorbidities. These differences need to be considered in daily clinical practice.

Unveiling Cardiac Amyloidosis, its Characteristics, and Outcomes Among Patients With MR Undergoing Transcatheter Edge-to-Edge MV Repair

BackgroundMitral regurgitation (MR) and cardiac amyloidosis (CA) both primarily affect older patients. Data on coexistence and prognostic implications of MR and CA are currently lacking. ObjectivesThis study sought to identify the prevalence, clinical characteristics, and outcomes of MR CA compared with lone MR. MethodsConsecutive patients undergoing transcatheter edge-to-edge repair (TEER) for MR at 2 sites were screened for concomitant CA using a multiparametric approach including core laboratory 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid bone scintigraphy and echocardiography and immunoglobulin light chain assessment. Transthyretin CA (ATTR) was diagnosed by 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid (Perugini grade 1: early infiltration; grades 2/3: clinical CA) and the absence of monoclonal protein, and light chain (AL) CA via tissue biopsy. All-cause mortality and hospitalization for heart failure (HHF) served as the endpoints. ResultsA total of 120 patients (age 76.9 ± 8.1 years, 55.8% male) were recruited. Clinical CA was diagnosed in 14 patients (11.7%; 12 ATTR, 1 AL, and 1 combined ATTR/AL) and early amyloid infiltration in 9 patients (7.5%). Independent predictors of MR CA were increased posterior wall thickness and the presence of a left anterior fascicular block on electrocardiography. Procedural success and periprocedural complications of TEER were similar in MR CA and lone MR (P for all = NS). After a median of 1.7 years, 25.8% had experienced death and/or HHF. MR CA had worse outcomes compared with lone MR (HR: 2.2; 95% CI: 1.0-4.7; P = 0.034), driven by a 2.5-fold higher risk for HHF (HR: 2.5; 95% CI: 1.1-5.9), but comparable mortality (HR: 1.6; 95% CI: 0.4-6.1). ConclusionsDual pathology of MR CA is common in elderly patients with MR undergoing TEER and has worse postinterventional outcomes compared with lone MR.

Combining electrocardiographic criteria for predicting acute total left main coronary artery occlusion.

BackgroundPrediction of left main artery (LM) occlusion may contribute to the administration of early reperfusion. We sought to identify electrocardiographic (ECG) features associated with acute total LM occlusion and explore the relationship between ECG features and collateral circulation.MethodsWe retrospectively studied ECGs in 84 consecutive patients with LM occlusion between January 2001 and April 2022. The ECG findings in these patients were compared with those in 468 consecutive patients with LM subtotal occlusion and non-LM occlusion.ResultsThree main ECG patterns were described according to the characteristics of ST elevation (STE) in LM occlusion: ST-segment elevation myocardial infarction (STEMI), STE in aVR with diffuse ST depression, and STE in both aVR and aVL. These ECG patterns were associated with different collateral filling territories. One-third STEMI in LM occlusion showed STE in the precordial leads including V1, while 2/3 STEMI showed STE in the precordial leads from V2 to V5 without STE in V1. The following ECG characteristics predicted LM occlusion: STE in both aVR and aVL; STE in I, aVL, and V2–V5 without V1; left anterior fascicular block (LAFB); right bundle branch block (RBBB) + LAFB; and prolongation of the QRS interval. The incidences of STE in aVR and STE in aVR and V1 were higher in LM subtotal occlusion than in LM occlusion. The combination of two different STE criteria (STE in aVR and aVL and STE in I, aVL, V2-V5 without V1) predicted LM occlusion with 62% sensitivity and 95% specificity. The combination of the STE criteria and fascicular block criteria (LAFB and LAFB + RBBB) further improved the specificity to 99% but reduced the sensitivity to 39%.ConclusionThe combination of STE criteria predicted LM occlusion with high specificity and moderate sensitivity, and the addition of fascicular block criteria further improved the specificity with some loss of sensitivity.

The effect of coronavirus infection on QT and QTc intervals of hospitalized patients in Qazvin, Iran

Electrocardiographic (ECG) changes have been investigated in the condition of coronavirus disease (COVID-19) indicating that COVID-19 infection exacerbates arrhythmias and triggers conduction abnormalities. However, the specific type of ECG abnormalities in COVID-19 and their impact on mortality fail to have been fully elucidated. The present retrospective, tertiary care hospital-based cross-sectional study was conducted by reviewing the medical records of all patients diagnosed with COVID-19 infection who were admitted to Booali Sina Hospital in Qazvin, Iran from March to July 2020. Demographic information, length of hospital stay, treatment outcome, and electrocardiographic information (heart rate, QTc interval, arrhythmias, and blocks) were extracted from the medical records of the patients. Finally, a total of 231 patients were enrolled in the study. Atrial fibrillation was a common arrhythmia, and the left anterior fascicular block was a common cardiac conduction defect other than sinus arrhythmia. The deceased patients were significantly older than the recovered ones (71 ± 14 vs. 57 ± 16 years, p < 0.001). Longer hospital stay (p = 0.036), non-sinus rhythm (p < 0.001), bundle and node blocks (p = 0.002), ST-T waves changes (p = 0.003), and Tachycardia (p = 0.024) were significantly prevalent in the deceased group. In baseline ECGs, no significant difference was observed in terms of the absolute size of QT; however, a prolonged QTc in the deceased was about twice of the recovered patients (using Bazett, Sagie, and Fridericia’s formula). Serial ECGs are recommended to be taken from all hospitalized patients with COVID-19 due to increased in-hospital mortality in patients with prolonged QTc interval, non-sinus rhythms, ST-T changes, tachycardia, and bundle, and node blocks.

Bundle branch block and nonspecific intraventricular conduction delay prevalence using Chinese nationwide survey data.

ObjectiveWe aimed to determine the prevalence of and the factors associated with intraventricular conduction disturbance in the Chinese population.MethodsElectrocardiographic data from 42,031 people were retrospectively analysed. The weighted prevalences of left bundle branch block (LBBB), right bundle branch block (RBBB), bifascicular block and nonspecific intraventricular conduction delay (NS-IVCD) were calculated. The independently associated factors were determined using logistic regression analysis.ResultsThe weighted prevalence for Chinese people older than 45 years was 0.17% for LBBB, 2.16% for RBBB and 0.44% for NS-IVCD. The weighted prevalence for RBBB combined with left anterior fascicular block was 0.17%, and 0.05% for RBBB combined with left posterior fascicular block. There were significant differences in the weighted prevalences of RBBB and NS-IVCD between men and women. The weighted prevalence of LBBB and RBBB increased markedly with increasing age. Age and diabetes were independent factors associated with LBBB, compared with age and sex for RBBB and sex and coronary artery disease for NS-IVCD.ConclusionsThis study provided reliable data for the weighted prevalence of and factors associated with LBBB, RBBB and NS-IVCD in Chinese adults.

Myocardial Injury in Patients With Acute and Subacute Chagas Disease in the Brazilian Amazon Using Cardiovascular MagneticResonance.

BackgroundChagas disease is a neglected tropical disease that is still considered a global health emergency. In the Amazon region, most of the reports are of acute cases that are associated with oral transmission. This study aimed to evaluate myocardial injury in patients with acute Chagas disease before and after treatment.Methods and ResultsWe evaluated 23 patients with acute Chagas disease in 3 different stages of progression. Group 1 had 12 patients evaluated during the acute phase, at the time of diagnosis, and 1 year after treatment, and Group 2 had 11 patients in the late postacute phase who were evaluated 5.2 years on average after diagnosis and treatment. ECGs with the Selvester score, 24‐hour Holter exam, and cardiovascular magnetic resonance imaging were performed. The mean age of the 23 patients was 44.3±18.9 years, and they were mostly men (15/65.24%) from Amazonas state (22/95.6%). In 69.6% (n=16) of the patients, some ECG alterations were found, the most frequent being left anterior fascicular block and ventricular repolarization. In Group 1, the 24‐hour Holter exam showed atrial tachycardia in 3 (25%) patients and ventricular extrasystoles in 2 (16.7%) patients. In Group 2, 1 patient had ventricular extrasystoles. Myocardial injury was observed in 7 patients (58.3%) at the acute phase and in 5 (50%) patients at the 1‐year follow‐up in Group 1 and in 2 (18.2%) patients in Group 2.ConclusionsThis article describes, for the first time, myocardial injury shown by cardiovascular magnetic resonance imaging in a group of patients with acute Chagas disease and reveals the importance of early detection and follow‐up of the cardiac impairment in these patients.

P144 PEMBROLIZUMAB–INDUCED MYOCARDITIS

Abstract Introduction Patients treated with Immunocheckpoint Inhibitors (ICI) can develop adverse cardiovascular events, most frequently myocarditis, but also arrhythmias, conduction abnormalities, pericarditis, Takotsubo syndrome, ACS, heart failure, cardiac arrest. Myocarditis occurs early, within the first 3–4 administrations of therapy, and is fraught with a high mortality rate. Case Presentation 80–year–old patient with renal pelvic carcinoma who underwent nephroureterectomy and subsequent adrenalectomy. Twenty days after the first cycle of Pembrolizumab, the patient is admitted to cardiology for syncope and ECG finding of Left Posterior Fascicular Block (LPFB) and right bundle branch block (RBBB) with significant increase in troponin without any alterations in regional kinetics and normal ventricular function (EF). The patient also complains of widespread muscle pain and severe hyponatremia on blood tests. On ECG monitoring, alternation of RBBB with associated LPFB and Left Posterior Fascicular Block, left bundle branch block, first and second degree atrio–ventricular block (AV block) and on day II appearance of complete paroxysmal AV block controlled with temporary pacemaker implantation. On the 4th day, we documented changes in the segmental motion of the left ventricle (LV) and progressive gradual worsening of the EF. During the hospitalization the patient manifested episodes of general malaise with profuse sweating and marked hypotension with possible SIADH picture. In suspicion of acute myocarditis, peripheral myositis and possible Pembrolizumab SIADH, the patient was treated with high dose methylprednisolone (1000 mg / day) with little benefit. On the 6th day the patient was found in critical condition, severely suffering, hypotensive and oliguric, resigned herself. Conclusions Our case highlights how even a single dose of Pembrolizumab can trigger an acute inflammatory pattern affecting the myocardium with prevalent involvement of the conduction tissue even before the appearance of alterations in the kinetics and ventricular dysfunction. During ICI therapy cycles it is therefore important to monitor the ECG and troponin levels in order to be able to diagnose myocardial involvement early. In fact, although this complication is rare, it is burdened by a high mortality rate. The only treatment currently available involves the suspension of immunotherapy and the administration of high–dose methylprednisolone.

P419 CARDIAC SARCOIDOSIS IN A CARRIER OF TTR GENE MUTATION

Abstract Abstract A 39–year–old man came to our attention after being identified as a carrier of the mutation lle68Leu in the transthyretin (TTR) gene, following his father’s diagnosis of cardiac amyloidosis. From then on, the patient underwent periodical follow–up for early detection of target organs involvement, with normal echocardiographic results of blood test and echocardiography. At the age of 41, he was hospitalized after a transient loss of consciousness (TLS) episode while riding a bicycle. The echocardiogram showed normal systolic function with an akinetic basal septum. A coronary angiogram excluded the presence of coronary artery disease. One year later, ECG abnormalities developed, with a new–onset right bundle branch block and posterior fascicular block. The echocardiogram showed a dilated cardiomyopathy with severe left systolic function impairment (ejection fraction 30%). SPECT with bisphosphonate ruled out cardiac amyloidosis. Cardiac MRI was significant for patchy areas of late gadolinium enhancement in the left ventricle. Before the following cardiological evaluation for a possible ICD implantation the patient was again hospitalized after a resuscitated cardiac arrest.Thoracic CT, performed in the emergency department, was significant for hilar lymphadenopathies and pulmonary nodules highly suggestive for sarcoidosis. FDG–PET showed multiorgan phlogistic–infiltrative involvement, including the myocardium. A subsequent hepatic CT–guided biopsy eventually confirmed the diagnosis of sarcoidosis. In secondary prevention, the patient underwent ICD implantation but continued to experience arrhythmic events.

P319 SOMETHING MORE OF SIMPLE CARDIAC CONDUCTION DISORDERS

Abstract Background Cardiac amyloidosis (CA) is an infiltrative disease caused by extracellular deposition of amyloid fibrils. Possible cardiac manifestations include heart failure with preserved ejection fraction (EF), aortic valve stenosis, microvascular coronary artery disease, atrial fibrillation (AF), ventricular arrhythmias, and cardiac conduction disorders (CCD). We report a case of advanced CCD in a patient first diagnosed with wild–type transthyretin amyloidosis (ATTRwt). Case Report An 88–year–old man went to Emergency Room for chest pain with minimal elevation of troponin I and increase in NTproBNP. The patient reported a recent syncope with ribs fractures. The medical history showed hypertension, paroxysmal AF, carotid atherosclerosis, vascular encephalopathy and prostate cancer. Troponin I monitoring showed plateau values and there were no clinical signs of heart failure. ECG showed regular sinus rhythm with marked first degree atrioventricular block, right bundle branch block and left anterior fascicular block (Fig. 1A). Cardiac telemetry recorded brief phases of atrioventricular dissociation (AVD). Transthoracic echocardiography showed severe left ventricular concentric hypertrophy (LVCH) with granular–sparkling appearance and preserved EF, reduced global longitudinal strain with apical sparing (Fig. 1B), mitral–aortic valve degeneration and dilation of the ascending aorta. Given the advanced CCD with AVD and the recent syncope, the patient underwent a dual–chamber pacemaker implantation. In consideration of the echocardiographic suspicion of CA, following Gillmore’s diagnostic algorithm (GDA), serum electrophoresis and assay of serum free light chains were performed and resulted normal, while 99mTc–DPD bone scintigraphy was positive for significant radiotracer cardiac uptake (Perugini grade 3) (Fig. 1C). Based on this result, we carried out the search for transthyretin gene mutations which resulted negative, and therefore the diagnosis of ATTRwt was made. Discussion Advanced CCD in patients with transthyretin CA are present in about 9.5% of cases at the time of diagnosis, especially in older patients. It is therefore essential, in case of concomitant LVCH, to suspect the presence of CA as the cause of CCD by searching for the disease red flags and following the GDA to non–invasively confirm or exclude the diagnosis of CA. A correct and timely diagnosis of CA makes it possible to treat the disease and its complications, improving the prognosis.

Group beating bradycardia due to two level AV junctional conduction block including combined Wenckebach and Mobitz 2 fascicular block

A case of a complex advanced two level AV junctional conduction block is described with electrocardiographic features consistent with the combination of incompletely concealed Wenckebach in the left anterior fascicle of the left bundle branch, and most probably in the right bundle branch and with Mobitz type II in the left posterior fascicle of the left bundle branch, resulting in intermittent trifascicular block.

Predicting permanent pacemaker implantation following transcatheter aortic valve replacement: A contemporary meta-analysis of 981,168 patients.

BackgroundHeart block requiring permanent pacemaker (PPM) implantation is a relatively frequent complication of transcatheter aortic valve replacement (TAVR).ObjectiveThe purpose of this study was to perform a contemporary meta-analysis to provide an updated assessment of clinically useful predictors of PPM implantation post-TAVR.MethodsMedline and EMBASE searches were performed to include all studies reporting PPM post-TAVR between 2015 and 2020. Pertinent data were extracted from the studies for further analysis. RevMan was used to create forest plots and calculate risk ratios (RRs).ResultsWe evaluated 41 variables from 239 studies with a total of 981,168 patients. From this cohort, 17.4% received a PPM following TAVR. Strong predictors for PPM implant were right bundle branch block (RBBB) (RR 3.12; P <.001) and bifascicular block (RR 2.40; P = .002). Intermediate factors were chronic kidney disease (CKD) (RR 1.53; P <.0001) and first-degree atrioventricular block (FDAVB) (RR 1.44; P <.001). Weak factors (RR 1–1.50; P <.05) were male gender, age ≥80 years, body mass index ≥25, diabetes mellitus (DM), atrial fibrillation (AF), and left anterior fascicular block (LAFB). These factors along with increased left ventricular outflow tract (LVOT) area (>435 mm2) and/or aortic annulus diameter (>24.4 mm) were incorporated to propose a new scoring system to stratify patients into high- and low-risk groups.ConclusionMale gender, age ≥80 years, FDAVB, RBBB, AF, DM, CKD, Medtronic CoreValve, transfemoral TAVR, increased LVOT, and aortic annulus diameter were significant predictors of post-TAVR PPM implantation. Preprocedural assessment should consider these factors to guide clinical decision-making before TAVR. Validation of our scoring system is warranted.

A community-based study on electrocardiographic abnormalities of adult population from South India - Findings from a cross sectional survey

BackgroundThere are no data on electrocardiographic (ECG) findings from general population of Indian subcontinent. We analyzed ECG abnormalities of in adults as part of a community survey of prevalence of coronary artery disease and risk factors from South India. Methods and resultsIn this cross-sectional study of men and women between the ages 20 to 79 years, ECGs recorded digitally were analyzed using the Minnesota code. Electrocardiograms were analyzed for abnormalities in 4630 participants (women 59.6%). The overall prevalence of ECG abnormalities (39.9%) was higher in men (47.24% vs. 34.9% p <0.0001). QRS axis deviation, first degree AV block, fascicular blocks, incomplete right bundle branch block, sinus bradycardia and ST elevation in the anterior chest leads were markedly higher in men. Sinus tachycardia and low voltage QRS occurred more often in women. The overall prevalence of atrial fibrillation was 0.32% which was markedly lower than the western data. Brugada and early repolarisation patterns occurred in 1.06% and 1.56% respectively, equal in both age groups, but markedly higher in men. Brugada pattern occurred more often than in the west, but much less than the Far East population. Early repolarisation pattern was similar to rest of Asian population, but significantly less than the Caucasian population ConclusionIn this community-based study, prevalence of major electrocardiographic abnormalities was high. Overall, men had significantly higher ECG abnormalities.

PO-672-06 SIMULTANEOUS HIS BUNDLE, LATERAL LV AND LATERAL RV PACING IN A PATIENT WITH REPAIRED TETRALOGY OF FALLOT

Patients with repaired Tetralogy of Fallot (ToF), who have RBBB and predominant right ventricular (RV) dysfunction may benefit from RV electromechanical resynchronization. We describe the case of a patient with repaired ToF, biventricular (BiV) dysfunction and ineffective cardiac resynchronization therapy (CRT) in whom His bundle pacing (HBP) fused with RV wall pacing achieved RV CRT and acute hemodynamic improvement. N/A 58 YOF with repaired ToF and BiV dysfunction presented with decompensated heart failure (HF). BiV implantable cardioverter-defibrillator (ICD) with RA, RV and coronary sinus (CS) leads (Biotronik, Berlin, Germany) was placed at an outside facility one year ago. Underlying EKG showed sinus rhythm with 1stdegree AVB (PR 240 ms), RBBB (QRSd 200ms) and left posterior fascicular block. With presenting CRT, QRS was wider (QRSd 240). Chest Xray revealed RV ICD lead in the right ventricular outflow tract (RVOT) and the CS lead in the anterior interventricular vein with the tip electrode also near RVOT. Given concern for suboptimal CRT, defibrillation vector and limited alternative options, we pursued individualized CRT optimization. Activation mapping showed latest RV activation in the basal lateral tricuspid annulus. Pacing from this site simultaneously with the His Bundle narrowed the QRS significantly and improved RVEF and dyssynchrony on intracardiac echocardiography. Fick cardiac output and index improved to 4.4 and 2.4 respectively from 3.7 and 2.0 at baseline. Thus, we removed the old CS lead and replaced the ICD lead with a new DF-1 defibrillator lead (Medtronic, Minneapolis, MN) in the RV apical septum. Then, we placed a SelectSecureTM His lead (3830 model, Medtronic, Minneapolis, MN). Non-selective His capture threshold was 1.0 V at 0.4 ms. Then, we placed a SelectSecureTM lead (3830 model, Medtronic, Minneapolis, MN) in the RV basal lateral wall and this was Y-adapted to a new LV lead (4196Y model, Medtronic, Minneapolis, MN) which was placed on a lateral branch of the CS. HBP fused with LV and RV lateral wall pacing resulted in a QRS of 120ms. At one year follow up, she has not had HF admissions. Simultaneous HBP and RV basal lateral wall pacing may be a feasible strategy for RV CRT in patients with ToF, RBBB and predominant RV dysfunction.

Cardiac Resynchronization Therapy In A Patient With Cardiac Allograft Vasculopathy

Background Reports describing cardiac resynchronization therapy (CRT) in patients with a cardiac allograft are limited to 2 cases in the setting of a new left bundle branch block. A case of CRT use and response in cardiac allograft vasculopathy (CAV) has not occurred to date. Objective Describe the use of CRT in a patient who developed CAV with right bundle branch block/left anterior fascicular block 5 years after orthotopic heart transplant (OHT). Methods N/A Results A 44-year old male with a history of non-ischemic cardiomyopathy, implantable defibrillator (ICD), and polycystic kidney disease received a dual heart and kidney transplant in May 2015. Annual right heart catheterization in May 2020 showed elevated biventricular filling pressures and cardiac index of 2 L/min/m2. Left heart catheterization showed early CAV. Endomyocardial biopsy results were negative for cellular or antibody-mediated rejection, and infiltrative/inflammatory processes. A transthoracic echocardiogram (ECHO) was significant for a depressed ejection fraction (25%), severe left ventricular global hypokinesis, and moderate to severe right ventricular dysfunction. Despite guideline-directed medical therapy consisting of sacubitril-valsartan, carvedilol, and spironolactone, cardiac function did not change on repeat ECHO. EP consultation noted the progression of ECG changes from a baseline narrow QRS complex post-OHT, to right bundle branch block (QRS 122 ms) January 2019, and right bundle branch block with left anterior fasicular block (QRS 150 ms) September 2020. A CRT-ICD was subsequently implanted. Biventricular pacing was initially set to no interventricular delay. An ECHO 3 months later showed significant improvement in cardiac function with a “mildly depressed” EF (42%), anterior/inferior dyskinesis, normalization of left ventricular end-diastolic dimension (4.8 cm from 5.5 cm), and right ventricular function. Electrocardiographic optimization changed the paced QRS width from 180 ms to 154 ms when left ventricular pacing was programmed 50 ms early, and minimized dyskinesis. Conclusion Response to CRT in OHT patients developing CAV cardiomyopathy with significant ventricular conduction delay can occur, and should be considered before more advanced heart failure therapies are applied. Reports describing cardiac resynchronization therapy (CRT) in patients with a cardiac allograft are limited to 2 cases in the setting of a new left bundle branch block. A case of CRT use and response in cardiac allograft vasculopathy (CAV) has not occurred to date. Describe the use of CRT in a patient who developed CAV with right bundle branch block/left anterior fascicular block 5 years after orthotopic heart transplant (OHT). N/A A 44-year old male with a history of non-ischemic cardiomyopathy, implantable defibrillator (ICD), and polycystic kidney disease received a dual heart and kidney transplant in May 2015. Annual right heart catheterization in May 2020 showed elevated biventricular filling pressures and cardiac index of 2 L/min/m2. Left heart catheterization showed early CAV. Endomyocardial biopsy results were negative for cellular or antibody-mediated rejection, and infiltrative/inflammatory processes. A transthoracic echocardiogram (ECHO) was significant for a depressed ejection fraction (25%), severe left ventricular global hypokinesis, and moderate to severe right ventricular dysfunction. Despite guideline-directed medical therapy consisting of sacubitril-valsartan, carvedilol, and spironolactone, cardiac function did not change on repeat ECHO. EP consultation noted the progression of ECG changes from a baseline narrow QRS complex post-OHT, to right bundle branch block (QRS 122 ms) January 2019, and right bundle branch block with left anterior fasicular block (QRS 150 ms) September 2020. A CRT-ICD was subsequently implanted. Biventricular pacing was initially set to no interventricular delay. An ECHO 3 months later showed significant improvement in cardiac function with a “mildly depressed” EF (42%), anterior/inferior dyskinesis, normalization of left ventricular end-diastolic dimension (4.8 cm from 5.5 cm), and right ventricular function. Electrocardiographic optimization changed the paced QRS width from 180 ms to 154 ms when left ventricular pacing was programmed 50 ms early, and minimized dyskinesis. Response to CRT in OHT patients developing CAV cardiomyopathy with significant ventricular conduction delay can occur, and should be considered before more advanced heart failure therapies are applied.

Electrocardiogram abnormalities in chronic Chagas cardiomyopathy correlate with scar mass and left ventricular dysfunction as assessed by cardiac magnetic resonance imaging

Electrocardiographic (ECG) abnormalities are frequently identified in Chronic Chagas cardiomyopathy (CCC) patients and advanced abnormalities are related to a worse prognosis. Cardiac Magnetic Resonance (CMR) can precisely assess ventricular systolic dysfunction and quantify myocardial fibrosis (MF), both identified as prognostic factors. We sought to investigate if ECG abnormalities in CCC patients were associated with more severe myocardial involvement as evaluated by CMR. MethodsCCC patients with 12‑lead ECG and CMR closely obtained were included. ECG analysis evaluated rhythm, presence, and type of intraventricular conduction disturbances (IVCD) and, ventricular premature beats (VPB). CMR short-axis cine and late gadolinium enhancement images were evaluated to obtain left and right ventricular ejection fractions and MF mass, respectively. Statistical significance was set in 5%. Results194 CCC patients (98 women, 56 ± 14 years) were evaluated, and no IVCD was detected in 71. The most common IVCD was the association of right bundle branch block and left anterior fascicular block (RBBB+LAFB) in 58 patients, followed by isolated RBBB in 34, isolated LAFB in 17, and left bundle branch block (LBBB) in 14 patients. Of patients with no IVCD, 63% had MF and the burden of fibrosis (no IVCD - 7.4 ± 8.6%; RBBB - 6.6 ± 6.5%; p = 1.00), as well as left ventricular ejection fraction (LVEF) (no IVCD - 52 ± 14%; RBBB - 55 ± 10%; p = 1.00) were similar to patients with isolated RBBB. Left conduction system impairment was associated with lower LVEF (LAFB - 39 ± 15%; RBBB+LAFB- 41 ± 15%; and LBBB - 35 ± 15%; p < 0.001) and more MF (RBBB+LAFB - 12.2 ± 10.4%; LBBB - 10.6 ± 7.5%; and LAFB - 12.0 ± 7.0%; p < 0.001). The univariable model showed that the presence of MF was related to RBBB+LAFB (OR 5.0; p = 0.001) and VPB (OR 6.3; p = 0.014). After adjustment for age, gender, and different risk factors in a multivariable model, the same findings were still significantly related to CMR myocardial fibrosis (RBBB+LAFB OR 5.0; p = 0.002 / VPB OR 6.9; p = 0.015). ConclusionsECG without IVCD does not exclude serious cardiac abnormalities in CCC, and isolated RBBB seems to have a benign course. The presence of VPB and left branch conduction impairment, especially LAFB associated with RBBB, indicate a more severe cardiac involvement.