Fragmented QRS complex in adult patients with Ebstein anomaly and its association with arrhythmic risk and the severity of the anomaly

Ebstein's anomaly in children and adults: multidisciplinary insights into imaging and therapy

Although survival has significantly improved in the last four decades, the diagnosis of Ebstein's anomaly is still associated with a 20-fold increased risk of mortality, which generally drops after neonatal period and increases subtly thereafter. With increasing age of presentation, appropriate timing of intervention is challenged by a wide spectrum of disease and paucity of data on patient-tailored interventional strategies. The present review sought to shed light on the wide grey zone of post-neonatal Ebstein's manifestations, highlighting current gaps and achievements in knowledge for adequate risk assessment and appropriate therapeutic strategy.A 'wait-and-see' approach has been adopted in many circumstances, though its efficacy is now questioned by the awareness that Ebstein's anomaly is not a benign disease, even when asymptomatic. Moreover, older age at intervention showed a negative impact on post-surgical outcome.In order to tackle the extreme heterogeneity of Ebstein's anomaly, this review displays the multimodality imaging assessment necessary for a proper anatomical classification and the multidisciplinary approach needed for a comprehensive risk stratification and monitoring strategy. Currently available predictors of clinical outcome are summarised for both operated and unoperated patients, with the aim of supporting the decisional process on the choice of appropriate therapy and optimal timing for intervention.

Electocardiographic features in Ebstein's disease

INTRODUCTION

Ebstein's disease (ED) is a rare and heterogeneous congenital heart disease affecting the tricuspid valve and the right ventricle. Few studies have analyzed the electrocardiographic features of this disease.

AIM

To describe the electrocardiographic features observed in Ebstein's disease.

METHODS

We conducted a retrospective descriptive study that enrolled 26 patients followed for ED.

RESULTS

The mean age of discovery of the ME was 103.5±99 months [0-31 years]. The diagnosis of ME is most often made between 5 and 10 years. We noted right atrial hypertrophy in 11 patients (42%), right ventricular hypertrophy in half of the patients. Right axial deviation was noted in 11 patients (42%). Eight patients (30%) had wide QRS≥ 120 ms. Seven of these 8 patients (27%) had a fragmented QRS appearance. A right bandle block was noted in 22 patients (84%), it was a complete block in 7 cases (27%). A preexcitation was found in 6 patients (23%). The localization of accessory pathway was right postero-septal in all cases. Rhythmic disorders were noted in 9 patients (34%). It was a junctional tachycardia in 3 patients (11%), atrial flutter in 4 patients (15%) and atrial fibrillation in 2 patients (7%). A second degree atriventricular block was observed in one patient, it was Mobitz I type. Two cases of postoperative rhythm disturbances were recorded: paroxysmal atrial fibrillation and junctional tachycardia related to Wolf Parkinson White (WPW) syndrome.

CONCLUSION

Surface ECG in the ED is often pathological with prevalence of rhythm disturbances related to WPW syndrome.

Presence of fragmented QRS may be associated with complex ventricular arrhythmias in patients with type-2 diabetes mellitus

BACKGROUND

Ventricular arrhythmias (VAs) are frequent in diabetes mellitus (DM) patients. Myocardial fibrosis is one of the components of diabetic cardiomyopathy secondary to DM. Fragmented QRS (fQRS) on electrocardiography (ECG) has been shown to be a marker of myocardial fibrosis. In this study, we aimed to investigate the association between fQRS and complex VAs in patients with DM.

METHODS

Three hundred and thirty-six consecutive patients who were diagnosed with DM were included in the study. The control group consisted of 275 age- and sex-matched healthy individuals. ECG and transthoracic echocardiography were performed in all the patients. fQRS was defined as additional R' wave or notching/splitting of S wave in two contiguous ECG leads. All the patients underwent 24-h Holter monitoring and VAs were classified using Lown's scoring system. Lown class ≥ 3 VAs were considered as complex VAs.

RESULTS

As compared to the healthy individuals, prevalence of fQRS (37.5% vs. 6.9%, p < .001) and complex VAs (14% vs. 0%, p < .001) were significantly higher in patients with DM. Furthermore, complex VAs (28.4% vs. 6.4%, p < .001) were significantly higher in DM patients with fQRS. In multiple logistic regression analysis, DM duration (OR: 1.510, 95% CI:1.343 to 1.698; p < .001) and presence of fQRS (OR: 3.262, 95% CI: 1.443 to 7.376; p = .004) were independent predictors for complex VAs.

CONCLUSIONS

The presence of fQRS may be associated with complex VAs in patients with DM. Therefore, fQRS may be used as a predictor of complex VAs and the risk of sudden death in patients with DM.

Diagnosis and treatment of right ventricular dysfunction in congenital heart disease

Right ventricular (RV) function is important for clinical status and outcomes in children and adults with congenital heart disease (CHD). In the normal RV, longitudinal systolic function is the major contributor to global RV systolic function. A variety of factors contribute to RV failure including increased pressure- or volume-loading, electromechanical dyssynchrony, increased myocardial fibrosis, abnormal coronary perfusion, restricted filling capacity and adverse interactions between left ventricle (LV) and RV. We discuss the different imaging techniques both at rest and during exercise to define and detect RV failure. We identify the most important biomarkers for risk stratification in RV dysfunction, including abnormal NYHA class, decreased exercise capacity, low blood pressure, and increased levels of NTproBNP, troponin T, galectin-3 and growth differentiation factor 15. In adults with CHD (ACHD), fragmented QRS is independently associated with heart failure (HF) symptoms and impaired ventricular function. Furthermore, we discuss the different HF therapies in CHD but given the broad clinical spectrum of CHD, it is important to treat RV failure in a disease-specific manner and based on the specific alterations in hemodynamics. Here, we discuss how to detect and treat RV dysfunction in CHD in order to prevent or postpone RV failure.

Fragmented QRS may be associated with complex ventricular arrhythmias in mitral valve prolapse

BACKGROUND

Although mitral valve prolapse (MVP) is a benign disease, several studies have indicated its association with ventricular arrhythmias (VAs). Some histopathological studies have pointed to left ventricular fibrosis as the underlying cause of arrhythmia in MVP patients. Fragmented QRS (fQRS) on electrocardiography (ECG) has been shown to be a marker of myocardial fibrosis. This study aimed to investigate the association between fQRS and complex VAs in patients with MVP.

METHODS

A total of 230 consecutive patients who were diagnosed with MVP were included in the study. The control group consisted of 302 healthy individuals matched according to age and sex. fQRS was defined as additional R' wave or notching/splitting of S wave in two contiguous ECG leads. All patients underwent 24-hour Holter monitoring and VAs were classified using Lown's scoring system. Lown class ≥3 VAs were considered as complex VAs.

RESULTS

As compared to the healthy individuals, prevalence of fQRS (40% vs. 9.6%, P<0.001) and complex VAs (18.7% vs. 0%, P<0.001) were significantly higher in patients with MVP. Furthermore, complex VAs (35.9% vs. 7.2%, P=0.001) were significantly higher in MVP patients with fQRS. In multiple logistic regression analysis, the presence of bileaflet prolapse (OR: 2.567, 95%CI: 1.434 to 4.367; P=0.002) and presence of fQRS (OR: 3.021, 95%CI: 1.556 to 6.232; P<0.001) were independent predictors for complex VAs.

CONCLUSIONS

The presence of fQRS may be associated with complex VAs in patients with MVP. Therefore, fQRS may be used in risk stratification of complex VAs in patients with MVP.

Electro-vectorcardiographic and electrophysiological aspects of Ebstein's anomaly

Ebstein's anomaly is a congenital heart disease where the most important anatomic feature is the inferior displacement of the tricuspid valve leaflets. Vectorcardiographic features are mainly forgotten and electrocardiographic features may be unrecognized by cardiologists handling adult patients.

Use of fragmented QRS in prognosticating clinical deterioration and mortality in pulmonary embolism: A meta-analysis

BACKGROUND

Fragmented QRS (fQRS) on electrocardiography is potentially valuable in prognosticating acute pulmonary embolism (PE). ECG is one of the first tests performed in the emergency department, quickly interpretable, noninvasive, inexpensive, and available in remote areas. We aimed to review fQRS's role in PE prognostication.

METHODS

We searched MEDLINE, EMBASE, Google Scholar, Web of Science, abstracts, conference proceedings, and reference lists until October 2017. Eligible studies used fQRS to prognosticate patients for the main outcomes of death and clinical deterioration or escalation of therapy. Two authors independently selected studies, with disagreement resolved by consensus. Ad hoc piloted forms were used to extract data and assess risk of bias. We used a random-effects model to pool relevant data in meta-analysis with odds ratios (OR) and 95% confidence intervals (CI), while all other data were synthesized qualitatively. Statistical heterogeneity was assessed using the I² index.

RESULTS

We included five studies (1,165 patients). There was complete agreement in study selection. fQRS significantly predicted in-hospital mortality (OR [95% CI], 2.92 [1.73-4.91]; p < .001), cardiogenic shock (OR [95% CI], 4.71 [1.61-13.70]; p = .005), and total mortality at 2-year follow-up (OR [95% CI], 4.42 [2.57-7.60]; p < .001). Adjusted analyses were generally consistent with these results.

CONCLUSION

Although few studies have explored the current study's question, they showed that fQRS is potentially valuable in PE prognostication. fQRS should be considered as an entry, along with other clinical and ECG findings, in a PE risk score.

Electrocardiographic Markers of Appropriate Implantable Cardioverter-Defibrillator Therapy in Young People with Congenital Heart Diseases

Implantable cardioverter-defibrillators (ICDs) are increasingly utilized in patients with congenital heart disease (CHD). Prediction of the occurrence of shocks is important if improved patient selection is desired. The electrocardiogram (ECG) has been the first-line tool predicting the risk of sudden death, but data in CHD patients are lacking. We aim to evaluate the predictive value of electrocardiographic markers of appropriate therapy of ICD in young people with CHD. We conducted a prospective, longitudinal study, in twenty-six CHD patients (mean age 24.7 ± 5.3 years) who underwent first ICD implantation. Forty-two age- and diagnosis-matched controls were recruited. Twelve-lead ECG and 24 h Holter analysis were performed during a mean follow-up of 38.9 months. Data included heart rate, heart rate variability, QRS duration (QRSd), QTc interval and its dispersion, Tpeak-Tend (Tp-Te) interval and its dispersion, presence of fragmented QRS (fQRS), T wave alternans, atrial arrhythmias, and non-sustained ventricular tachycardia. Implant indication was primary prevention in ten cases (38.5%) and secondary prevention in 16 (61.5%). Overall, 17 subjects (65.3%) received at least one appropriate and effective ICD discharge. fQRS was present in 64.7% of cases with ICD therapy compared with patients without events or controls (p < 0.0001). Tp-e and Tp-e dispersion were significantly prolonged in patients with recurrences (113.5 and 37.2 ms) versus patients without ICD discharge (89.6 and 24.1 ms) or controls (72.4 and 19.3 ms) (p < 0.0001 and p < 0.0001, respectively). On univariate Cox regression analysis QRSd (hazard ratio: 1.19 per ms, p = 0.003), QTc dispersion (hazard ratio: 1.57 per ms, p = 0.002), fQRS (hazard ratio: 3.58 p < 0.0001), Tp-e (hazard ratio: 2.27 per ms, p < 0.0001), and Tp-e dispersion (hazard ratio: 4.15 per ms, p < 0.0001), emerged as strong predictors of outcome. On multivariate Cox analysis fQRS, Tp-e and Tp-e dispersion remained in the model. The presence of fQRS, and both Tp-e and Tp-e dispersion are useful ECG tools in daily clinical practice to identify CHD patients at risk for appropriate ICD therapy.

The Difference on Features of Fragmented QRS Complex and Influences on Mortality in Patients with Acute Coronary Syndrome

Objectives

To investigate whether the fragmented QRS (fQRS) complexes can be used to distinguish patients with early non-ST elevation myocardial infarction (NSTEMI) from those with unstable angina (UA).

Background

fQRS complex has been found to be linked to myocardial infarction and cardiac death.

Methods

The clinical data of 302 patients who had been diagnosed with coronary artery disease were retrospectively reviewed. Incidence of fQRS complex within 48 h of presentation was analyzed and patients with acute myocardial infarction (AMI) (n = 240) were followed up by telephone interviews for a mean of 61.47 (range, 59.60-63.35) months.

Results

Patients with NSTEMI exhibited higher incidence of fQRS than those with UA (p = 0.047). The incidence of fQRS in the inferior wall leads was significantly higher than that of other leads in patients with anterior wall infarction (p < 0.05). Kaplan-Meier analysis revealed a higher mortality rate in AMI patients with fQRS compared to non-fQRS patients (p = 0.001).

Conclusions

Presence of fQRS complexes within 48 hours of presentation may be used to differentiate NSTEMI patients from UA patients. fQRS may also be used as a survival predictor for patients with AMI.

Major adverse events and atrial tachycardia in Ebstein's anomaly predicted by cardiovascular magnetic resonance

Objectives

Patients with Ebstein’s anomaly of the tricuspid valve (EA) are at risk of tachyarrhythmia, congestive heart failure and sudden cardiac death. We sought to determine the value of cardiovascular magnetic resonance (CMR) for predicting these outcomes.

Methods

Seventy-nine consecutive adult patients (aged 37±15 years) with unrepaired EA underwent CMR and were followed prospectively for a median 3.4 (range 0.4–10.9) years for clinical outcomes, namely major adverse cardiovascular events (MACEs: sustained ventricular tachycardia/heart failure hospital admission/cardiac transplantation/death) and first-onset atrial tachyarrhythmia (AT).

Results

CMR-derived variables associated with MACE (n=6) were right ventricular (RV) or left ventricular (LV) ejection fraction (EF) (HR 2.06, 95% CI 1.168 to 3.623, p=0.012 and HR 2.35, 95% CI 1.348 to 4.082, p=0.003, respectively), LV stroke volume index (HR 2.82, 95% CI 1.212 to 7.092, p=0.028) and cardiac index (HR 1.71, 95% CI 1.002 to 1.366, p=0.037); all remained significant when tested solely for mortality. History of AT (HR 11.16, 95% CI 1.30 to 95.81, p=0.028) and New York Heart Association class >2 (HR 7.66, 95% CI 1.54 to 38.20, p=0.013) were also associated with MACE; AT preceded all but one MACE, suggesting its potential role as an early marker of adverse outcome (p=0.011).

CMR variables associated with first-onset AT (n=17; 21.5%) included RVEF (HR 1.55, 95% CI 1.103 to 2.160, p=0.011), total R/L volume index (HR 1.18, 95% CI 1.06 to 1.32, p=0.002), RV/LV end diastolic volume ratio (HR 1.55, 95% CI 1.14 to 2.10, p=0.005) and apical septal leaflet displacement/total LV septal length (HR 1.03, 95% CI 1.00 to 1.07, p=0.041); the latter two combined enhanced risk prediction (HR 6.12, 95% CI 1.67 to 22.56, p=0.007).

Conclusion

CMR-derived indices carry prognostic information regarding MACE and first-onset AT among adults with unrepaired EA. CMR may be included in the periodic surveillance of these patients.

Ebstein Anomaly With QRS Fragmentation on Electrocardiogram

Ebstein anomaly is a rare congenital disorder that involves the tricuspid valve and the right ventricle. It is associated with interatrial communication, which allows for paradoxical embolization causing unilateral blindness. Abnormal conduction through the atrialized right ventricle leads to QRS fragmentation on electrocardiogram. Its presence suggests a more severe abnormality and a higher risk of arrhythmia. The QRS fragmentation disappears after corrective surgery with resection of the atrialized right ventricle.

Short-term Prognosis of Fragmented QRS Complex in Patients with Non-ST Elevated Acute Myocardial Infarction

Background:

There remains significant debate as to the relationship between fragmented QRS (fQRS) complexes on electrocardiogram (ECG) and acute myocardial infarction (AMI). Few studies have reported on this relationship in non-ST elevated AMI (NSTEMI), and thus, we attempt to assess this relationship and its potential short-term prognostic value.

Methods:

This was a single-center, observational, retrospective cohort study. A total of 513 consecutive patients (399 men, 114 women) with NSTEMI within 24 h who underwent coronary angiography at our department, between January 1, 2014, and December 31, 2014. Patients were divided into 2 groups according to the presence or absence of fQRS complex on the admission ECG. fQRS complexes were defined as the existence of an additional R’ or crochetage wave, notching in the nadir of the S wave, RS fragmentation, or QS complexes on 2 contiguous leads. All patients were followed up for 6 months, and all major adverse cardiac events (MACE) were recorded.

Results:

In this study, there were 285 patients with fQRS ECG in the 513 patients with NSTEMI. The number of patients with 0–2 coronary arteries narrowed by ≥50% in fQRS group were less while patients with 3 narrowed arteries were more than in the non-fQRS group (P = 0.042). There were fewer Killip Class I patients in the fQRS group (P = 0.019), while Killip Class II, III, and IV patients were more in the fQRS group than in the non-fQRS group (P = 0.019). Left ventricular ejection fraction levels were significantly lower in the fQRS group (P = 0.021). Baseline total cholesterol, low-density lipoprotein, creatinine, creatine kinase, homocysteine, high-sensitivity C-reactive protein (CRP), and red blood cells distribution width levels were significantly higher in the fQRS group. Total MACE (MACE, P = 0.028), revascularization (P = 0.005), and recurrent angina (P = 0.005) were also significantly greater in the fQRS group. On final logistic regression analysis, after adjusting for baseline variables, the following variables were independent predictors of fQRS: Coronary artery narrowing (P = 0.035), Killip classification (P = 0.026), and total cholesterol (P = 0.002). The following variables were found to be independent predictors of preoperative MACE: Hemoglobin (P = 0.000), gender (P = 0.026), fQRS (P = 0.016), and time from myocardial infarction to balloon or coronary artery bypasses grafting (P = 0.013).

Conclusions:

The fQRS complexes are commonly present in NSTEMI and the fQRS complexes are an independent predictor of MACE in NSTEMI patients. The number of narrowed coronary arteries, Killip classification, and total cholesterol are all independent predictors of the fQRS complexes.

Usefulness of Fragmented QRS Complexes in Patients With Congenital Heart Disease to Predict Ventricular Tachyarrhythmias

Fragmented QRS complexes (fQRS) on 12-lead electrocardiogram are known predictors of ventricular tachyarrhythmia (VTA) in patients with coronary artery disease. There is limited knowledge of the clinical implications of fQRS in patients with congenital heart defects (CHD). Aims of this study were to examine (1) the occurrence of fQRS in patients with various types of CHD and (2) whether fQRS is associated with development of VTA. This study was designed as retrospective case-control study. Patients with CHD with VTA were included and matched with control patients of the same age, gender, and CHD type. Clinical data and fQRS were analyzed and compared. The initial VTA episode developed in 139 patients with CHD at a mean age of 39 ± 14 years. Compared with controls (n = 219, age 38 ± 13 years), QRS duration was longer in patients with VTA (110 vs 100 ms; p <0.01). Furthermore, fQRS was more frequently observed in patients with VTA in the last electrocardiogram before VTA (n = 73 [53%] vs n = 67 [31%]; p <0.001), especially in patients with sustained VTA (64%). Multiple conditional logistic regression demonstrated more fQRS (odds ratio [OR] 2.9, 95% confidence interval [CI] 1.5 to 5.8; p = 0.002), nonsystemic ventricular dysfunction (OR 5.1, 95% CI 2.1 to 12.4; p <0.001), and more prolonged QRS complexes (OR 2.8, 95% CI 1.3 to 6.2; p = 0.011) in patients with VTA. Therefore, the presence of fQRS on electrocardiogram may be a useful tool in daily clinical practice to identify patients at risk for developing VTA in patients with CHD, in addition to known predictors of VTA.

Essential ECG clues in patients with congenital heart disease and arrhythmias

The prevalence of adults with congenital heart disease has dramatically increased during the last decades due to significant advances in the surgical correction of these conditions. As a result, patient's survival has been prolonged and arrhythmias have become one of the principal causes of morbidity and mortality for these patients. The surface 12-lead ECG may play a critical role in the identification of the underlying heart disease of the patient, the recognition of the arrhythmia mechanism and may also help in the planification of the ablation procedure in this setting. Finally, important prognostic information can be also obtained from the ECG in these patients. The present review will offer an overview of the principal utilities of the surface ECG in the diagnosis and management of patients with CHD and arrhythmias.

Fragmented QRS Complex Predicts In-Hospital Adverse Events and Long-Term Mortality in Patients with Acute Pulmonary Embolism

BACKGROUND

Electrocardiographic (ECG) abnormalities in pulmonary embolism (PE) are increasingly reported, and mounting data have recommended that ECG plays a crucial role in the prognostic assessment of PE patient population. However, there is scarce data on the prognostic importance of fragmented QRS (fQRS) on short- and long-term outcomes in patients with PE. Therefore, we aimed to investigate the prognostic role of fQRS in predicting in-hospital and long-term adverse outcomes in PE patients.

METHODS

A total of 249 patients (155 female, 66.2%; mean age, 66.0 ± 16.0) with the diagnosis of acute PE were enrolled and followed-up during median 24.8 months.

RESULTS

Compared with the fQRS (-) patient group, patients with fQRS showed higher rates of in-hospital adverse events including cardiogenic shock, the necessity of thrombolytic therapy, and in-hospital mortality as well as long-term all-cause mortality. In Kaplan-Meier survival analysis, during follow-up, all-cause mortality occurred more frequently in the fQRS (+) group (log-rank, P = 0.002). In multivariate Cox regression analysis, adjusted with other relevant parameters, the presence of fQRS were determined as an independent predictor of in-hospital adverse events (HR: 2.743, 95% CI: 1.267-5.937, P = 0.003) and long-term all-cause mortality (HR: 3.137, 95% CI: 1.824-6.840, P = 0.001).

CONCLUSIONS

The presence of fQRS complex, as a simple and feasible ECG marker, seems to be a novel predictor of in-hospital adverse events and long-term all-cause mortality in PE patient population. This parameter may utilize the identification of patients whom at higher risk for mortality and individualization of therapy.

Fragmented QRS on surface electrocardiogram is not a reliable predictor of myocardial scar, angiographic coronary disease or long term adverse outcomes

PURPOSE

Conflicting evidence remains regarding the value of fragmented QRS (fQRS) on surface electrocardiogram (EKG). We present the 5-year outcome of patients with fQRS on EKG and its correlation to SPECT and coronary angiography (CA).

METHODS

We retrospectively studied EKG's in 248 consecutive patients undergoing SPECT and CA with known or suspected coronary artery disease (CAD). The presence of fQRS or Q waves in two contiguous EKG leads was correlated with major coronary artery distributions on SPECT and cath. Patients with bundle-branch block, paced-rhythm or absence of EKG within one month of SPECT were excluded. The final EKG data for 238 patients were analyzed and compared with myocardial scar on SPECT and the presence of significant (>50%) coronary stenosis on CA. Predictors of MACE (death, MI, heart failure) were evaluated. Freedom from all-cause mortality was assessed by Kaplan-Meier analysis.

RESULTS

Of 238 patients, no significant difference was noted in the presence of scar on SPECT in fQRS (3/77; 3.8%) versus no fQRS (11/161; 6.8%) (P=0.56); or CA based CAD (55/77; 71% fQRS) and no fQRS (99/161, 61.4%) (P=0.20). EKG Q wave presence was similar in both groups: (12/77; 15.5% fQRS), (17/161; 10.5% no fQRS) (P=0.3). Patients with CA based significant LAD disease were 3.680 times more likely to have fQRS (P=0.04), however, fQRS was not significantly associated with MACE (P=0.92) or all-cause mortality (P=0.93).

CONCLUSIONS

This study does not support routine assessment of fQRS on surface EKG as a reliable predictor of SPECT myocardial scar, MACE or all-cause mortality over a long period of follow-up.

Variations of QRS Morphology in Patients with Dilated Cardiomyopathy; Clinical and Prognostic Implications

The QRS represents the simultaneous activation of the right and left ventricles, although most of the QRS waveform is derived from the larger left ventricular musculature. Although normal QRS duration is <100 millisecond (ms), its duration and shape are quite variable from patient to patient in idiopathic dilated cardiomyopathy (IDCM). Prolongation of QRS occurs in 14% to 47% of heart failure (HF) patients. Left bundle branch block (LBBB) is far more common than right bundle branch block (RBBB). Dyssynchronous left ventricular activation due to LBBB and other intraventricular conduction blocks provides the rationale for the use of cardiac resynchronization therapy with biventricular pacing in patients with IDCM. Fragmented QRS (fQRS) is a marker of depolarization abnormality and present in significant number of the patients with IDCM and narrow QRS complexes. It is associated with arrhythmic events and intraventricular dyssynchrony. The purpose of this manuscript is to present an overview on some clinical, echocardiographic and prognostic implications of various QRS morphologies in patients with IDCM.