QRS Duration Research Articles

Conduction Disorders after Rapid Deployment Aortic Valve Replacement Compared to Conventional Aortic Valve Replacement.

We evaluated and compared early postprocedural and midterm incidence and evolution of atrioventricular and intraventricular conduction disorders following rapid deployment aortic valve replacement (RDAVR) and conventional aortic valve replacement (AVR). One hundred and forty-seven patients who underwent isolated rapid deployment AVR between 2017 and 2021 as well as 128 patients after conventional biological AVR in the same period were included in this study. ECGs recorded at baseline, discharge, and 12 months were retrospectively analyzed. Intrinsic rhythm, PQ interval, QRS duration, and atrioventricular and intraventricular conduction were evaluated and compared between both groups. Patients in both groups had comparable Society of Thoracic surgeons risc (STS) scores (2.9 ± 1.6 vs. 3.1 ± 2.2, p = 0.32) and comparable baseline characteristics. The mean age was 73.4 ± 5.7 years in the RDAVR group and 74.2 ± 5.9 years in the AVR group, respectively. At baseline, the mean QRS width was 95.7 ± 25.5 ms in the RDAVR group, and 97.3 ± 23.5 ms in the AVR group, respectively (p = 0.590). At discharge, the mean QRS width in the RDAVR group was significantly increased with 117.4 ± 28.6 ms and a mean ΔQRS width of 21.7 ± 26.3 ms (p < 0.001) compared with baseline. No significant changes in QRS width were found in the AVR group with a mean value of 101.2 ± 24.1 ms and a mean ΔQRS width of 3.9 ± 23.9 ms at discharge (p = 0.193). The left bundle branch block (LBBB) was increased in the RDAVR group after 12 months (19.3% vs. 5.1%, p < 0.001). Permanent pacemaker implantation (PPI) rates were significantly higher in the RDAVR group after 12 months (hazard ratio (HR): 4.68; 95% CI: 2.23-7.43, p < 0.001). Mortality did not differ between both groups after 12 months (HR: 1.09; 95% CI: 0.46-1.83, p = 0.835) CONCLUSION: Patients after RDAVR showed significantly higher rates of LBBB and PPI after 12 months. However, higher mortality was not observed in the RDAVR group.

Right ventricular subclinical dysfunction in high-burden idiopathic outflow tract premature ventricular contraction population.

The relationship between premature ventricular contractions (PVC) and right ventricular (RV) function is not widely known. Left ventricular (LV) dysfunction due to PVC is known as PVC-induced cardiomyopathy (PIC) and suppressing the PVC substrate would improve LV function. The effect of PVC ablation on changes in RV function in patients with subtle RV subclinical dysfunction remains unknown. Understanding the alterations in RV function parameters after PVC ablation. Basic and speckle-tracking echocardiography has been performed on 42 individuals with symptomatic idiopathic outflow tract PVC before and 1 month after a successful ablation. At the baseline of the study, there were 26 patients with RV subclinical dysfunction and 16 patients without RV dysfunction. Patients with RV subclinical dysfunction exhibited significantly higher PVC burden and QRS complex duration than those with normal RV function (p < 0.05). A PVC burden ≥ 21% (OR 9.11, 1.54-53.87, p = 0.015) and a QRS complex duration ≥ 138 ms (OR 5.74, 1.07-30.90, p = 0.042) were independently associated with RV subclinical dysfunction. In both groups, measurements of RV subclinical function before and after ablation, specifically by free wall longitudinal strain (FWLS) and global longitudinal strain (GLS), demonstrated significant changes. These improvements were more pronounced in the group with RV dysfunction (FWLS 9.7 ± 4.0, p < 0.001; GLS 7.5 ± 4.2, p < 0.001). Lower initial FWLS and GLS before ablation emerged as significant parameters in the multivariate analysis for the improvement of RV function post-ablation. Patients with RV subclinical dysfunction had higher PVC burden and wider QRS duration. Patients with idiopathic outflow tract PVC with RV subclinical dysfunction may experience improvements in RV function after successful PVC ablation.

Maternal autoimmune systemic connective tissue disease and vasculitis and electrocardiographic findings in the offspring.

Maternal autoimmune systemic connective tissue diseases (CTDs) and their related antibodies have been associated with adverse fetal outcomes, including complete heart block. In this study, we assessed the association between maternal CTD or vasculitis and neonatal electrocardiographic (ECG) parameters. Our study population was drawn from the Copenhagen Baby Heart Study (CBHS), a prospective, population-based cohort study open to all neonates born in the Copenhagen area. All CBHS neonates born to mothers with CTD or vasculitis were matched 1:3 to neonates born to mothers without these diseases on sex, gestational age, age and weight at time of examination, and maternal age at delivery. Maternal CTD and vasculitis diagnoses were validated through medical record review. Our primary analyses compared ECG parameters for exposed and unexposed neonates overall. Where numbers allowed, subanalyses were then conducted by specific CTD diagnoses and autoantibody types. Among 17,862 CBHS neonates with an available ECG, 40 neonates of mothers with CTDs or vasculitis (50% males, median age 12 [interquartile range 8-16] days) were matched to unexposed neonates. Overall, no significant differences in heart rate, PR interval, QRS axis, QRS duration, QT/QTc interval, or R- or S-wave amplitudes were found when comparing exposed and unexposed neonates (all p>0.05). Similarly, separate analyses of the 10 neonates with anti-Ro/SSA-positive mothers and their matched comparators revealed no significant between-group differences. However, neonates born to mothers with antiphospholipid syndrome (n=15) had a significantly longer QRS duration (median 56ms vs. 52ms, p=0.02) and corrected QT interval (median QTcBaz 430ms vs. 414ms, p=0.01), compared with matched unexposed neonates. In this population-based study, no significant overall differences in ECG parameters were found between neonates exposed to maternal CTD or vasculitis and unexposed neonates. However, neonates exposed to maternal antiphospholipid syndrome had significantly longer QRS- and QTc intervals than unexposed neonates. The potential clinical implications of these findings are unknown and, combined with the limitations of this study, warrant further investigation in larger cohorts.

Efficacy and safety of the adenosine administration test in the management of Wolff-Parkinson-White pattern in children with delta waves.

The Wolff-Parkinson-White pattern is a delta wave frequently detected in school-based cardiovascular screening programs in Japan. Although most children with Wolff-Parkinson-White pattern are asymptomatic, initial symptoms may include syncope or sudden death, necessitating accurate diagnosis and management. Delta waves can also indicate a fasciculoventricular pathway, which poses no risk and does not require management. We reviewed the medical records of patients referred to our hospital between April 2008 and March 2022 to evaluate the electrocardiographic signs of the Wolff-Parkinson-White pattern. The existence of Wolff-Parkinson-White syndrome and fasciculoventricular pathway were determined based on atrioventricular block and QRS waveform changes after adenosine administration during sinus rhythm. The study cohort included 127 children (65 males; median age: 12.8 years, resting heart rate: 75 beats/min, PR interval: 109 ms, and QRS duration: 101 ms). The adenosine administration test revealed a fasciculoventricular pathway, Wolff-Parkinson-White syndrome, and indeterminate findings in 64, 54, and 9 children, respectively. More than 60% of children with a QRS duration ≤ 120 ms had a fasciculoventricular pathway. Age ≤ 12 years, QRS duration >120 ms, and type A category (children with R/S ratios >1 in lead V1) were identified as independent risk factors for Wolff-Parkinson-White syndrome. No adverse events were observed in any child. The adenosine administration test is safe and feasible for differentiating Wolff-Parkinson-White syndrome from fasciculoventricular pathways and can reduce the unnecessary management of children with fasciculoventricular pathways.

A new insight into the anatomical ablation approach at R-L ILT for VAs with a left ventricular summit origination: electrophysiological characteristics and catheter ablation.

Ventricular arrhythmia (VA) originating from the left ventricular summit (LVS) poses particular challenges, with higher rates of ablation failure. To further evaluate the anatomical ablation approach from the subaortic region for LVS VAs and their electrophysiological characteristics. The study enrolled 27 consecutive patients with sympatomatic VAs originating from LVS and who received an anatomical ablation approach from R-L ILT in our center. Three different mapping results were obtained as the earliest activation sites (EAS) were observed in the RVOT region (group 1), R-L ILT (group 2), and epicardial region (group 3), respectively. A higher percentage of rS/QS patterns in lead I was observed in Groups 1 and 3. A narrower QRS duration was observed in Group (1) A presystolic potential was recorded at R-L ILT for most VAs in group (2) All VAs were successfully ablated at R-L ILT in groups 1 and 2, though poor pace mapping results were observed at R-L ILT. 4/7 VAs in group 3 ultimately failed after an ablation in both the endocardial and epicardial regions. An anatomical ablation approach at R-L ILT was effective for most VAs with an LVS origin. Different ECG and electrophysiological characteristics could be observed in VAs with different EAS. Poor pace mapping results in all regions with an EAS in the epicardial region had predictive value for the failure of the ablation procedure.

Left Bundle Branch Area Pacing Versus Right Ventricular Pacing in Patients With Atrioventricular Block: A Systematic Review and Meta-Analysis.

Left bundle branch area pacing (LBBAP) is a new technique for patients with atrioventricular block (AVB) and preserved left ventricular ejection fraction (LVEF), potentially offering better cardiac function than right ventricular pacing (RVP). We searched databases and registries for studies that compared LBBAP with RVP in patients with AVB and preserved LVEF. We extracted data on various outcomes and pooled the effect estimates using random-effects models. Our meta-analysis included 14 studies (10 observational and 4 RCTs) involving 3062 patients with AVB. The analysis revealed that the QRS duration was significantly shorter in the LBBAP group compared to the RVP group [MD = -35.56 ms; 95% CI: (-39.27, -31.85), p < 0.00001]. Patients in the LBBAP group also exhibited a significant increase in left ventricular ejection fraction (LVEF) [MD = 5.48%; 95% CI: (4.07%, 6.89%), p < 0.00001], and a significant reduction in left ventricular end-diastolic diameter (LVEDD) compared to RVP [MD = -3.98 mm; 95% CI: (-5.88, -2.09 mm), p < 0.0001]. In terms of clinical outcomes, LBBAP was associated with a significantly lower risk of heart failure hospitalizations (HFHs) compared to RVP [OR = 0.26; 95% CI: (0.16, 0.44), p < 0.0001]. However, no significant differences were observed between the two groups in the implant success rate, pacing impedance, or pacing threshold. The RVP group demonstrated a significantly higher R-wave amplitude increase than the LBBAP group [MD = 0.85 mV; 95% CI: (0.23, 1.46), p = .007]. Lastly, there was no significant difference in the incidence of complications between the two groups [OR = 2.12; 95% CI: (0.29, 15.52), p = 0.46]. LBBAP outperforms RVP in several cardiac function indicators, suggesting it may be a superior pacing method for AVB patients with preserved LVEF. However, the small sample size in studies and the result in heterogeneity call for more research to validate these findings and assess LBBAP's long-term effects.

Comparison of 6-lead smartphone ECG and 12-lead ECG in athletes and a genetic heart disease population

ABSTRACT Background Smartphone electrocardiograms (iECGs) are an innovative method of capturing transient arrhythmias which are occasionally experienced by athletes. This study aimed to assess the accuracy of a 6-lead iECG compared with 12-lead ECG in athletes and those with known genetic heart disease (positive controls). Research design and methods Each participant had a resting 12-lead ECG (supine) and a 30 second 6-lead iECG (seated) taken within 2 hours. Manual measurements of heart rate, QTc and PR intervals, and QRS duration were completed using digital calipers. Bland-Altman analysis was used to assess the quantitative agreement of measurements. Results The 6-lead readings for heart rate were faster than the 12-lead in athletes (n = 233) and positive controls (n = 49). All other measurements were shorter in the 6-lead. QTc mean difference was smaller in the positive controls (4.7 ± 26.0 ms) than in athletes (12.5 ± 25.0 ms). The largest difference was in PR intervals, both in athletes (12.8 ± 17.7 ms) and positive controls (7.6 ± 18.9 ms). QRS duration had the smallest mean difference (0.6 ± 9.0 ms in athletes, 1.0 ± 12.7 ms in positive controls). Conclusions The 6-lead readings had reasonable agreement with the 12-lead ECG. A 6-lead iECG is a reasonable option to opportunistically capture arrhythmias that may occur infrequently, but should not replace a 12-lead if available.

A Novel Electrocardiographic Marker for Predicting Total Mortality in Ischemic Stroke: Frontal QRS-T Angle.

This study aimed to investigate the relationship between mortality and the frontal QRS-T angle (FQRS-TA), obtained by calculating the absolute difference between the QRS and T waves electrocardiographically (ECG), in patients diagnosed with ischemic stroke (IS). This research is a retrospective and cross-sectional study. The diagnosis of IS was confirmed through brain imaging and physical examination. Patients with sinus rhythm were included in the study. The FQRS-TA was measured by calculating the absolute difference between the QRS-axis and the T-axis, as automatically measured on the ECG. Patients were divided into two groups: those who died within five years and those who survived, and the groups were compared. A total of 322 patients with IS were included in the study, of whom 290 survived, and 32 died. Age, creatinine level, PR interval, QRS duration, corrected QT (cQT) value, and FQRS-TA value were found to be higher in the deceased group. Cox regression analyses were performed to examine the association between predictors of stroke-related mortality. Age [hazard ratio (HR): 1.091, 95% (1.045-1.140), P < 0.001], high-density lipoprotein (HDL) [HR: 0.914, 95% (0.875-0.955), P < 0.001], and FQRS-TA [odds ratio (OR): 1.011, 95% (1.003-1.019), P = 0.007] were associated with mortality. A FQRS-TA of 68 degrees or higher was associated with cumulative mortality in the Kaplan-Meier survival analysis (log rank [Mantel-Cox] test: P = 0.001). In this study, increased FQRS-TA was found to be associated with mortality in patients with IS. ECG parameters are simple and time-efficient measurements that can provide important prognostic information. To the best of our knowledge, this research is the first study to examine the relationship between FQRS-TA and mortality in patients with IS.

Electrocardiographic Changes in Pregnant Patients With Congenital Heart Disease For the STORCC Investigators.

Electrocardiograms (EKGs) are routinely performed in pregnant patients with pre-existing cardiovascular disease. However, in pregnant patients with congenital heart disease (CHD), EKG changes during gestation have not been explored. We performed a retrospective study of pregnant patients with CHD enrolled in the STORCC initiative. Patients were included if they had at least two EKGs across the perinatal period and were grouped by specific conditions: atrial septal defect (ASD), tetralogy of Fallot, congenital pulmonary stenosis, coarctation of the aorta (CoA), bicuspid aortic valve (BAV), systemic right ventricle (SRV), and Fontan circulation. EKG parameters were measured in all available EKGs by two investigators, blinded to diagnosis and time of gestation. One hundred and seventy pregnant patients were included. There was a statistically significant increase in HR from pre-pregnancy to third trimester in all groups except for those with Fontan and SRV. Patients with ASD and BAV had a statistically significant increase in their QTc (ASD:13 ms, p = 0.017; BAV:7 ms, p = 0.018) during pregnancy. QRS duration was shorter (4 ms) in the third trimester for patients with ASD (p = 0.033) and CoA (p = 0.014). Despite these individual findings, EKG parameters remained within normal limits and regressed to baseline in the postpartum period. Patients with CHD have statistically significant EKG changes throughout pregnancy, but the values remain within normal limits. Like patients without heart disease, those with CHD increase their HR during pregnancy, except individuals with SRV and Fontan, who appear to lack capacity for physiologic HR augmentation.

Heart remodelling affects ECG in rat DOCA/salt model.

Myocardial remodelling involves structural and functional changes in the heart, potentially leading to heart failure. The deoxycorticosterone acetate (DOCA)/salt model is a widely used experimental approach to study hypertension-induced cardiac remodelling. It allows to investigate the mechanisms underlying myocardial fibrosis and hypertrophy, which are key contributors to impaired cardiac function. In this study, myocardial remodelling in rat deoxycorticosterone acetate/salt model was examined over a three-week period. The experiment involved 11 male Sprague-Dawley rats, divided into two groups: fibrosis (n=6) and control (n=5). Myocardial remodelling was induced in the fibrosis group through unilateral nephrectomy, deoxyco-rticosterone acetate administration, and increased salt intake. The results revealed significant structural changes, including increased left ventricular wall thickness, myocardial fractional volume, and development of myocardial fibrosis. Despite these changes, left ventricular ejection fraction was preserved and even increased. ECG analysis showed significant prolongation of the PR interval and widening of the QRS complex in the fibrosis group, indicating disrupted atrioventricular and ventricular conduction, likely due to fibrosis and hypertrophy. Correlation analysis suggested a potential relationship between QRS duration and myocardial hypertrophy, although no significant correlations were found among other ECG parameters and structural changes detected by MRI. The study highlights the advantage of the DOCA/salt model in exploring the impact of myocardial remodelling on electrophysiological properties. Notably, this study is among the first to show that early myocardial remodelling in this model is accompanied by distinct electrophysiological changes, suggesting that advanced methods combined with established animal models can open new opportunities for research in this field. Key words Myocardial fibrosis, Remodelling, Animal model, DOCA-salt, Magnetic resonance imaging.

Smoking-associated electrocardiographic abnormalities predict cardiovascular mortality

Background —Smoking is associated with arrhythmia and sudden cardiac death, but the biological mechanisms remain unclear. In electrocardiogram (ECG) recordings abnormal durations of ventricular repolarization (QT interval), atrial depolarization (P wave), and atrioventricular depolarization (PR interval and segment), predict cardiac arrhythmia and mortality. Previous analyses of the National Health and Nutrition Examination Survey (NHANES) database for associations between smoking and ECG abnormalities were incomplete. To elucidate how smoking affects cardiac excitation, we assessed in a nationally representative sample (NHANES III) the association between serum cotinine and P duration, PR interval, PR segment, rate-corrected QT (QTc), QRS duration, and JT interval. Methods and Results—We analyzed data from 5,653 adults using survey-weighted multinomial logistic regression to estimate associations between tobacco use (> 15 ng/ml serum cotinine) and short (< 5th percentile) or long (> 95th percentile) ECG intervals, relative to reference (5–95th percentile). After adjustment for demographics, risk factors, and conduction-altering medications, smoking was associated with a higher odds of short PR interval, PR segment, and QRS, and long JT. Broader effects of smoking on ECG were also assessed by survey-weighted linear regression of continuous cotinine and ECG, which revealed cotinine inversely associated with PR segment and QTc. Over a 22-year follow-up, many ECG abnormalities predicted cardiovascular mortality in smokers, including long JT, QRS, and QTc, and short QRS, whereas only short JT predicted mortality in nonsmokers. Conclusions —Smoking increases likelihood for rapid atrioventricular and ventricular depolarization and slow ventricular repolarization, which may promote cardiac arrhythmia and mortality.

'Pacing System Analyzers to guide Conduction System Pacing implantation procedures: A comparison study of intracardiac and surface signals with an Electrophysiological Recording System'.

Left bundle branch area pacing (LBBAP) needs confirmation of left conduction system capture assessed by testing of different electrical parameters. Guidelines recommend the use of an electrophysiological recording-system (EP-RS) to guide conduction system pacing (CSP) procedures. However, some experienced centers perform LBBAP procedures without an EP-RS. We aimed to assess whether LBBAP criteria can be measured using the signals provided by the pacing system analyzers (PSA) as a surrogate for the EP-RS to simplify and universalize the technique. This was an observational, prospective, multicenter study assessing the current LBBAP criteria using the PSA compared to the EP-RS during CSP procedures. 108 consecutive patients were included. Baseline QRS duration was 130±29 vs 128±29msec in the EP-RS vs PSA (p=0.7). An initial "W" morphology in V1 was noted in 88% patients with the EP-RS vs 86% patients with the PSA (p=0.7) during unipolar pacing. The QRS duration (122±17 vs 123±19 msec, p=0.7), the R-wave peak time interval in V6 (80±13 vs 79±14 msec (p=0.9) and the V6-V1 inter-peak interval (39±16 vs 38±17 msec (p=0.7) were superimposable in the EP-RS compared to the PSA. Pearson coefficient for the last two criteria were 0.85 (p<0.0001) and 0.94 (p<0.0001), respectively. According to the current criteria, 91.5% of patients received a successful LBBAP implant using the EP-RS. Based on the PSA measurements, 96.6% of these patients accomplished LBBAP criteria. Criteria for LBBAP can be assessed by PSAs with high accuracy. These results provide the basis for the usefulness of the PSA to guide LBBAP procedures.

Deep Septal Pacing for Pacemaker-Induced Cardiomyopathy.

Right ventricular (RV) pacing can impair left ventricular function and cause heart failure, known as pacing-induced cardiomyopathy (PICM). Upgrade to cardiac resynchronization (CRT) is its usual treatment; recently left bundle branch area pacing (LBBAP) has emerged as a potential alternative. Deep septal pacing (DSP), a simplified alternative to LBBAP, is still able to achieve narrower paced QRS than during conventional RV pacing. The aim of this study was to assess the effect of DSP in a cohort of patients with PICM. Consecutive patients diagnosed with PICM were included. The aim was to upgrade patients to DSP. The procedure was considered successful if a paced QRS duration ≤140ms was obtained, in the absence of a terminal R wave in V1. Twelve patients were included. The mean baseline LVEF was 33% (SD 4%), and the mean percentage of RV pacing was 99% (SD 1%). All patients had symptomatic heart failure. The mean paced QRS duration was 172ms (SD 14ms) with RV pacing, and 130ms (SD 7ms) with DSP (mean difference 42ms, p<0.001). At 6 months, the mean LVEF after the upgrade was 46% (SD 9%), significantly superior to LVEF with RV pacing (p = 0.001), a mean improvement of 13% (SD 10%). All patients except one experienced an improvement in LVEF of at least 5%. Our data suggest that DSP may be an effective and simpler alternative to biventricular or LBBAP in patients with PICM. Narrower paced QRS complexes can be achieved, which may lead to an improvement in left ventricular function.

Catheter Ablation of Idiopathic Left Anterior Fascicular Ventricular Arrhythmias: Predicting Origin Sites via Mapping and Electrocardiography

ABSTRACTBackgroundIdiopathic ventricular arrhythmias (VAs) arising from the left anterior fascicle (LAF) are uncommonly seen, and their characteristics still need to be sufficiently investigated. This study aimed to conclude these VAs' characteristics and explore efficient ablation strategies.MethodsData were analyzed from 118 patients undergoing successful catheter ablation for LAF VAs. Patients were divided into three groups based on target sites in LAF: proximal‐LAF group (n = 30, from the common trunk of the left bundle branch to the LAF below the right coronary cusp (RCC), middle‐LAF group (n = 35, the LAF below the RCC and left coronary cusp (LCC), distal‐LAF group (n = 53, the LAF below LCC to the LAF terminal).ResultsFrom proximal‐ to distal‐LAF, VAs showed a gradually decreased Purkinje‐ventricular (PV) and His‐ventricular (HV) interval. For proximal‐LAF VAs, a distance from the sites recorded with the earliest Purkinje potential to RCC of 4.08 ± 1.03 mm predicted successful ablation in RCC. There are significant differences among the three groups in QRS duration, R/S ratio in V6, and Lead I. Using these three ECG characteristics as a panel to predict the origin of LAF VAs, the area under curve (AUC) was 0.96% and 95% confidence interval (CI) was 0.916–1.0 in the proximal‐ and middle‐LAF group, the AUC was 0.998 and 95% CI was 0.994–1.0 in the middle‐ and distal‐LAF group.ConclusionWhen LAF is anatomically divided into proximal, middle, and distal segments, QRS duration and R/S ratio in Leads V6 and I are available to predict the origin and promote a successful catheter ablation. In addition, combining these three ECG characteristics as a panel can better facilitate the prediction of LAF‐VA origin.

Leucocyte telomere length and conduction system ageing

BackgroundDeterioration of the cardiac conduction system is an important manifestation of cardiac ageing. Cellular ageing is accompanied by telomere shortening and telomere length (TL) is often regarded as a marker...

Progression and prognostic significance of electrocardiographic findings in patients with cardiac amyloidosis.

This study aimed to evaluate the change of the main electrocardiographic (ECG) characteristics and their prognostic role across the main subtypes of cardiac amyloidosis [light-chain amyloidosis (AL) and hereditary (ATTRv) and wild-type transthyretin amyloidosis (ATTRwt)]. This multicentre, retrospective study was performed in six referral centres for cardiac amyloidosis. Clinical and ECG data were collected at the first and last evaluations. Three hundred fifty-six patients were included (AL, n=105; ATTRv, n=50; ATTRwt, n=201). The median age was 76 (67-81) years, and 271 (74%) were men. At baseline, patients with ATTRwt showed a higher prevalence of conduction abnormalities compared with those with AL [first-degree atrioventricular block, n=51 (40%) vs. n=13 (34%), P<0.01; left bundle branch block, n=23 (11%) vs. n=2 (2%), P<0.01], and patients with AL more often had low QRS voltage [n=58 (55%); in ATTRv, n=17 (34%); in ATTRwt, n=67 (33%), P value<0.01] and T wave inversion compared with those with ATTR [n=39 (37%); in ATTRv, n=9 (18%); in ATTRwt, n=37 (18%)]. After a median follow-up of 15 (8-26) months, the adjusted differences in mean PR, QRS interval, total, peripheral, and precordial QRS scores were similar across subtypes of amyloidosis (P value for linear regression>0.05). The adjusted odds ratios for the development of right bundle branch block were higher in AL compared with ATTRwt [odds ratio 4.7 (95% confidence interval 1.5-15), P<0.05]. QRS duration at baseline remained independently associated with patient survival in the overall population even after adjustment for relevant clinical variables [hazard ratio 1.78 (95% confidence interval 1.13-2.8), P<0.01]. The progression of the ECG abnormalities seems similar across amyloidosis subtypes. QRS duration could be a marker of more advanced disease.

Electrocardiographic Early Changes After Abdominoplasty.

Abdominoplasty aims to reduce the abdominal excess tissue and tighten the abdominal wall. The tightening of the abdominal wall has structural and habitual consequences on the body, which might have an early effect on electrocardiography (ECG) of the patients through volumetric and pressure changes in thoracic and abdominal cavities. ECG serves as a diagnostic tool for assessing cardiac electrical conductions in routine clinical practice. In this study, we aimed to examine whether abdominoplasty has any discernible effect on early ECG results, with the goal of assessing potential cardiological benefits for the patients undergoing this procedure by comparing pre- and early postoperative ECGs. Study population included 49 patients who had abdominoplasty. ECG records before the procedure and 12-24h after the surgery were analyzed retrospectively. Patients had no known cardiac diseases and did not have any diagnosed arrhythmia. The mean age of the study population was 37.1 ± 8.5. The mean body mass index of the study population was 26.4. The mean weight of total removed abdominal skin tissue was 1057 grams. There were significant changes in ECG of the patients postoperatively. Heart rate was increased, and significant change was found in QRS axis (p < 0.001) and T wave axis (p < 0.001). Atrial conduction parameters such as PR duration (p < 0.001), Pmax duration (p = 0.001) and P-wave dispersion (p = 0.003) were significantly changed postoperatively. Ventricular conduction parameters such as QRS duration (p = 0.029), QT interval (p < 0.001), QTc (p < 0.001), TPe duration (p < 0.001), TPe / QT (p < 0.001) and TPe / QTc (p < 0.001) ratios were found significantly changed. Abdominoplasty changes the intra-abdominal pressure in the first 24h after the surgery, which may impact cardiac conduction. The understanding and recognition of possible early ECG changes is crucial during postoperative follow-up of the patients who undergo abdominoplasty surgery. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Myocardial strain analysis by cardiac magnetic resonance associated with arrhythmias in repaired tetralogy of Fallot patients

BackgroundEvaluating myocardial function using cardiac magnetic resonance (CMR) feature tracking provides a comprehensive cardiac assessment, particularly a detailed evaluation for patients with repaired tetralogy of Fallot (rTOF). This study aimed to identify factors associated with arrhythmias in rTOF patients utilizing conventional CMR techniques, including myocardial strain measurements.MethodsThis single-center, retrospective study included 245 rTOF patients who underwent CMR between 2017 and 2023. Patients were stratified based on the presence or absence of arrhythmias during follow-up. The biventricular strain was assessed using CMR-derived feature tracking. Demographic, clinical, and imaging data were collected, and statistical analyses were performed to identify factors associated with arrhythmic events.ResultsThe median age at surgery was 5.6 years (range 1–44 years), with the median age at CMR was 27.5 years (range 15–69 years). Over the follow-up period, 25 patients (10.2%) experienced atrial or ventricular arrhythmias. Univariate analysis revealed significant associations between arrhythmic events and older age at surgery and CMR, lower functional class, larger heart size on chest radiograph, and prolonged QRS duration (QRSd). Additionally, arrhythmias were associated with increased right ventricular (RV) volume, reduced RV and left ventricular (LV) ejection fraction (EF), and impaired strain values. Multivariate binary logistic regression, adjusting for age at surgery, NYHA class, QRSd, and cardiothoracic ratio, identified that a lower RV EF (adjusted odds ratio [aOR] 6.97), RV global radial strain (GRS) (aOR 6.68), RV global circumferential strain (GCS) (aOR 6.36), RV global longitudinal strain (GLS) (aOR 3.14), and LV GRS (aOR 3.02) were all significantly associated with arrhythmias.ConclusionThis study highlights the significant contribution of CMR-derived myocardial strain measurements in predicting arrhythmic events in patients with rTOF. In addition to conventional RV EF, strain metrics—particularly those of the right ventricle- emerged as strong, independent predictors of arrhythmias, offering valuable prognostic information for clinical management in this patient population. These findings underscore the importance of myocardial strain analysis as a complementary tool to conventional imaging in evaluating arrhythmic risk in rTOF patients.Clinical trial numberNot applicable.

Holter Monitoring and Cardiac Biomarkers in Screening for Cardiac Sarcoidosis.

Early detection of cardiac sarcoidosis (CS) is crucial due to its association with severe complications such as ventricular arrhythmias, heart failure, and sudden cardiac death. Advanced imaging techniques like cardiac magnetic resonance imaging (CMR) and 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (FDG-PET/CT) are effective in detecting CS but not easily accessible. The optimal method for selecting patients for advanced screening remains uncertain. In this retrospective cohort study, all extracardiac sarcoidosis patients screened for CS were reviewed. CS was defined as a multidisciplinary team (MDT) consensus diagnosis. Univariate and multivariate binary logistic regressions were used to identify factors associated with CS, assessing their diagnostic performance, and integrating them into a diagnostic model. Out of 354 patients (average age 51.5 years, 52.5% male), 18.4% were diagnosed with CS. In our cohort, male gender, a QRS duration > 120 ms, and nsVT on Holter monitoring were identified as significant markers associated with CS. Combining age, gender, AV-block or QRS > 120ms on ECG, and nsVT on Holter monitoring provided the highest diagnostic accuracy (AUC of 0.82). Cardiac biomarkers NT-proBNP and troponin T did not improve the diagnostic performance. In our cohort, male gender, a QRS duration > 120 ms, and nsVT on Holter monitoring were identified as significant markers associated with the presence of cardiac sarcoidosis. These clinical markers may aid in selecting sarcoidosis patients for screening with advanced cardiac imaging, potentially leading to earlier detection and management of the disease.

Autocorrelation maps for optimal setting in cardiac resynchronization therapy

Background and ObjectivePatients with chronic heart failure are treated with implanted devices artificially stimulating the ventricular myocardium to support the ventricular activation propagation dynamics. The criterion for stimulation/pacing timing is a shortening of the QRS duration in the ECG signal. The study suggests additional ECG parameters that could be helpful in cardiac resynchronization therapy (CRT) device pacing settings. MethodsThis issue was approached by computing and evaluating autocorrelation maps derived from body surface potential maps during the QRS complex. The autocorrelation maps were calculated from the body surface potential maps of seventeen patients, fourteen of whom were diagnosed with the left bundle branch block (LBBB) and three with the right bundle branch block (RBBB). Eleven of the LBBB patients were responders, and all three RBBB patients and three LBBB patient were non-responders. The body surface potential maps were measured during their spontaneous heart rhythm and optimal CRT setting. The patients’ autocorrelation maps were compared with the autocorrelation maps of a control group of 33 healthy persons using two-sample Kolmogorov-Smirnov and Wilcoxon rank-sum statistical tests. ResultsThe autocorrelation maps from spontaneous rhythm were significantly different (p < 0.00008) in healthy and LBBB groups, which was shown on 19 parameters extracted from the autocorrelation maps by both the statistical tests of equality. In the optimal CRT setting in the LBBB responders, four of the studied parameters (Shannon entropy of the histogram of the autocorrelation map's values, and mean, standard deviation, and geometrical mean of the autocorrelation map's positive values) were not significantly different from the parameters of the healthy subjects (p > 0.19). ConclusionsSelected parameters of autocorrelation maps can be used as additional parameters for optimal CRT pacing settings, leading to patients’ positive responses to the treatment.