Fragmented Wide QRS on a 12-Lead ECG

A Perplexing ECG

An unusual appearing electrocardiogram (ECG) is sent to the medical director's department for interpretation prior to receiving the actual life insurance application. As a result, no background details are available to provide a clinical context. Preliminary perusal of the ECG suggests several diagnostic possibilities.

Identifying delayed left ventricular lateral wall activation in patients with non-specific intraventricular conduction delay using coronary venous electroanatomical mapping

Background

Delayed left ventricular (LV) lateral wall activation is considered the electrical substrate that characterises patients suitable for cardiac resynchronisation therapy (CRT). Although typically associated with left bundle branch block, delayed LV lateral wall activation may also be present in patients with non-specific intraventricular conduction delay (IVCD). We assessed LV lateral wall activation in a cohort of CRT candidates with IVCD using coronary venous electroanatomical mapping, and investigated whether baseline QRS characteristics on the ECG can identify delayed LV lateral wall activation in this group of patients.

Methods

Twenty-three consecutive CRT candidates with IVCD underwent intra-procedural coronary venous electroanatomical mapping using EnSite NavX. Electrical activation time was measured in milliseconds from QRS onset and expressed as percentage of QRS duration. LV lateral wall activation was considered delayed if maximal activation time measured at the LV lateral wall (LVLW-AT) exceeded 75 % of the QRS duration. QRS morphology, duration, fragmentation, axis deviation, and left anterior/posterior fascicular block were assessed on baseline ECGs.

Results

Delayed LV lateral wall activation occurred in 12/23 patients (maximal LVLW-AT = 133 ± 20 ms [83 ± 5 % of QRS duration]). In these patients, the latest activated region was consistently located on the basal lateral wall. QRS duration, and prevalence of QRS fragmentation and left/right axis deviation, and left anterior/posterior fascicular block did not differ between patients with and without delayed LV lateral wall activation.

Conclusion

Coronary venous electroanatomical mapping can be used at the time of CRT implantation to determine the presence of delayed LV lateral wall activation in patients with IVCD. QRS characteristics on the ECG seem unable to identify delayed LV lateral wall activation in this subgroup of patients.

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 and ejection fraction in heart failure patients admitted to the hospital

Background

Fragmented QRS (FQRS) in 12 lead ECG was recently correlated with various outcomes in ischemic and non-ischemic heart disease. We studied the relationship between FQRS and ejection fraction (EF) in heart failure patients with QRS < 120 ms.

Methods

Medical records and echocardiograms of 339 patients admitted with CHF were reviewed. ECGs were read twice by a reader blinded to all data.

Results

70 patients with wide QRS were excluded; 63 patients had FQRS and 206 patients did not have FQRS. FQRS group were more likely to be black (OR = 2.17; p = 0.0093), and diabetic (OR = 1.79; p = 0.0451). ROC curve analysis revealed a significant relationship between EF and FQRS (p = 0.002). At EF of 48%, OR for FQRS was 4.36 (95% CI: 2.1–9.05; p < .0001). Adjustment for race and diabetes did not change the OR, or confidence intervals (Adjusted OR for race: 4.08 (95% CI: 1.06–15.67; p = 0.04); for diabetes: 4.13 (95% CI: 1.46–11.69; p = 0.008)). There was a significant difference in EF between patients with FQRS involving ≥ 2 ECG areas and non-FQRS group (p < 0.05), but not between patients with ≥ 2 vs. one area, or 1 area vs. non-FQRS.

Conclusion

In heart failure patients with QRS < 120 ms, FQRS was observed more frequently in persons of black race and in diabetics and was associated with lower EF. This was mainly seen in patients with FQRS involving ≥ 2 ECG areas.

Fragmented QRS complexes have predictive value of imperfect ST-segment resolution in patients with STEMI after primary percutaneous coronary intervention

OBJECTIVES

To investigate the clinical characteristics of patients with the fragmented QRS complexes (fQRS) and the predictive value of fQRS in patients undergoing primary percutaneous coronary intervention (p-PCI).

METHODS

The study enrolled 227 consecutive patients with ST-elevation myocardial infarction who underwent p-PCI. Baseline clinical characteristics, the percentage of ST-segment resolution, and parameters of electrocardiography and coronary angiography were investigated. The relationship between fQRS on pre-PCI and post-PCI electrocardiogram and the percentage of ST-segment resolution after PCI were studied.

RESULTS

Patients with fQRS have higher troponin I, creatine kinase-MB levels, prolonged QRS duration, higher Gensini score, lower percentage of total ST-segment resolution, and left ventricular ejection fraction compared with patients without fQRS. Gensini score (odds ratio [OR], 1.013; 95% confidence interval [CI], 1.002-1.024; P < .006) and percentage of total ST-segment resolution (OR, 0.384; 95% CI, 0.186-0.795; P = .01) were independently associated with the presence of fQRS. A multivariate logistic regression analysis selected presence of fQRS pre-PCI (OR, 2.908; 95% CI, 1.095-7.723; P = .032) and the number of leads with fQRS before PCI (OR, 1.582; 95% CI, 1.250-2.002; P < .001) as independent predictors of imperfect ST-segment resolution.

CONCLUSIONS

The presence of fQRS is a predictor in ST-elevation myocardial infarction patients undergoing p-PCI. The occurrence of fQRS is beneficial to identify the patients with severe coronary lesion, left ventricular contraction dysfunction, and larger areas of ischemic injury.

Electrocardiographic Predictors of Cardiovascular Mortality

Cardiovascular diseases are the main causes of mortality. Sudden cardiac death may also appear in athletes, due to underlying congenital or inherited cardiac abnormalities. The electrocardiogram is used in clinical practice and clinical trials, as a valid, reliable, accessible, inexpensive method. The aim of the present paper was to review electrocardiographic (ECG) signs associated with cardiovascular mortality and the mechanisms underlying those associations, providing a brief description of the main studies in this area, and consider their implication for clinical practice in the general population and athletes. The main ECG parameters associated with cardiovascular mortality in the present paper are the P wave (duration, interatrial block, and deep terminal negativity of the P wave in V1), prolonged QT and Tpeak-Tend intervals, QRS duration and fragmentation, bundle branch block, ST segment depression and elevation, T waves (inverted, T wave axes), spatial angles between QRS and T vectors, premature ventricular contractions, and ECG hypertrophy criteria.

Fragmented QRS Is Associated with Improved Predictive Value of Exercise Treadmill Testing in Patients with Intermediate Pretest Likelihood of Significant Coronary Artery Disease

BACKGROUND

The predictive value of exercise treadmill testing (ETT) remains inadequate in diagnosing patients with suspected coronary artery disease (CAD) and needs to be improved.

OBJECTIVE

The aim of this study was to investigate whether the presence of FQRS on 12-lead ECG would increase the PPV of ETT in patients with an intermediate likelihood of CAD.

METHODS

fQRS, defined as the presence of notched R or S waves without accompanying typical bundle branch block or the existence of an additional wave-like RSR' pattern in the original QRS complex (with a duration of <120 ms), was assessed in 95 patients with positive ETT. Coronary angiogram (CA) was performed in all patients, divided into two groups as the significant CAD group and nonsignificant CAD group according to coronary artery lesions. The differences between the groups in terms of the presence of fQRS and clinical characteristics were investigated.

RESULTS

The mean age of patients was 51.3 ± 11.3 years, and 74 of them were males (77.9%). FQRS was present in 47 (49.5%) patients, and significant CAD was demonstrated in 51 subjects (53.7%) among the enrolled subjects. fQRS was more prevalent in the significant CAD group compared to nonsignificant CAD group (P < 0.001). The presence of FQRS increased the PPV of positive ETT from 53.7% to 85.1%. In addition, FQRS was associated with the increased risk of significant CAD in multivariate analysis (OR = 2.839, P < 0.001).

CONCLUSION

In clinical practice, the presence of fQRS in patients with positive ETT may support clinicians during the decision-making process with regard to the referral for a coronary angiography.

Methodology for automated detection of fragmentation in QRS complex of Standard 12-lead ECG

Fragmented QRS (f-QRS) has been found to have higher sensitivity and/or specificity values for several diseases including remote and acute myocardial infarction, cardiac sarcoidosis etc, compared to other conventional bio-markers viz. Q-wave, ST-elevation etc. Several of these diseases do not have a reliable bio-marker and hence, patients suffering from them have to undergo expensive and sometimes invasive tests for diagnosis viz. myocardial biopsy, cardiac catheterization etc. This paper proposes automation of fragmentation detection which will lead to a more reliable diagnosis and therapy reducing human error, time consumption and thereby alleviating the need of enormous training required for detection of fragmentation. In this paper, we propose a novel approach to detect the discontinuities present in QRS complex of standard 12-lead ECG, known as fragmented QRS, using Discrete Wavelet transform (DWT) targeting both hospital-based and remote health monitoring environments. Fragmentation Detection Algorithm (FDA) was designed and modeled using PhysioNet's PTBDB and upon reiterative refinements it successfully detected all discontinuities in the QRS complex. The QRS complexes of 31 patients obtained randomly from PhysioNet's PTBDB were examined by two experienced cardiologists and the measurements obtained were compared with the results of our proposed FDA leading to 89.8% agreement among them.

Electrocardiographic evolution in patients with hypertrophic cardiomyopathy who develop a left ventricular apical aneurysm

INTRODUCTION

Hypertrophic cardiomyopathy (HCM) patients with apical aneurysm have a largely unfavourable clinical course, and are often unrecognised because echocardiography is limited in the assessment of the left ventricular (LV) apex. The aim of this study is the identification of electrocardiographic (ECG) abnormalities associated with the development of apical aneurysm in HCM patients.

MATERIALS AND METHODS

Electrocardiographic features were assessed in 14 HCM patients who had a good-quality baseline ECG recorded before and after the diagnosis of apical aneurysm.

RESULTS

During follow-up (8.8±7.5years), the following ECG changes were observed: increase in QRS-complex duration (87±12ms to 118±34ms, p=0.006), QRS-complex fragmentation, decrease in QRS-complex amplitude (SV1+RV5-6, from 41±18mm to 26±11mm, p=0.015), ST-segment elevation in V4-V6 (J-point in V5, from -0.9±1.3mm to +0.7±1.3, p=0.003), positivisation of negative T waves in V3-V6 (T-wave depth in V5, from -3.4±6.6 to +3.1±4.1, p=0.005).

CONCLUSIONS

HCM patients who develop LV apical aneurysm exhibit distinctive ECG changes along with apical remodelling. Suggestive ECGs should lead the physician to study LV apex by nonstandard echocardiographic views, and perform MRI.

Radiotherapy Induces Development of Fragmented QRS in Patients with Breast Cancer

BACKGROUND

Myocardial fibrosis is a well-known side effect of radiotherapy. Fragmented QRS (fQRS) has been shown to be a marker of myocardial fibrosis. We postulated that radiotherapy induces development of fQRS in breast cancer patients.

PATIENTS AND METHODS

Breast cancer patients receiving locoregional radiotherapy were enrolled. Patients who had fQRS on electrocardiography (ECG) before radiotherapy were excluded. All patients were revaluated for the development of fQRS at 1-year follow-up. An age-matched healthy group served as controls.

RESULTS

A total of 52 breast cancer patients receiving locoregional radiotherapy were included (median age 49 years, interquartile range (IQR) 13). Of these, 19 (37%) had developed fQRS at 1-year follow-up. Compared with the control group, prevalence of fQRS was significantly higher in the irradiated group (37 vs. 12%; p < 0.002). Median total cardiac radiation dose was significantly higher in patients who had developed fQRS (5 Gy, IQR 5.2 vs. 1.7 Gy, IQR 4.4; p = 0.003). Cardiac radiation dose, entered either as a continuous variable (odds ratio (OR) 1.35, 95% confidence interval (CI) 104-1.74) or as a dichotomized variable (≥ 2.2 Gy, OR 6.48, 95% CI 1.47-28.61), was independently associated with the development of fQRS at 1-year follow-up.

CONCLUSION

Radiotherapy for breast cancer induces development of fQRS on ECG. Cardiac radiation dose is independently associated with the development of fQRS.

Pathophysiological links, echocardiographic characteristics, and clinical implications of QRS morphology in patients with dilated cardiomyopathy

Heart failure is an important clinical problem worldwide. There is great interest in evaluating the relationship between electrocardiographic variations and dilated cardiomyopathy (DCM) since it has been used as a predictor of increased morbidity and mortality. The presence of fragmentation in the QRS complexes on 12-lead electrocardiogram (ECG) was reported as a marker of depolarization abnormality in patients with DCM. Previous studies have investigated the relation between QRS morphology and DCM. QRS morphology and duration are associated with clinical deterioration and increased mortality in patients with DCM. Although surface ECG provides valuable information on prognosis of these patients, echocardiographic methods have been used for further investigation of patients with DCM. The aim of the present review is to provide an overview of the pathophysiological links, echocardiographic characteristics and clinical implications of QRS morphology in patients with DCM.

Usefulness of notched duration to predict response to cardiac resynchronization therapy

OBJECTIVES

The presence of notches in the biventricular paced QRS complex (BiP-QRS) from the posterolateral cardiac vein displays delays in the activation of the left ventricle and may consequently be linked with longer times of stimulus conduction. Our objective was to determine the relationship between the notch duration ≥ 0.1 mV in the BiP-QRS and the effectiveness of cardiac resynchronization therapy (CRT).

DESIGN

A total of 210 patients, who underwent de novo CRT implantation previously and had ≥ 1 follow-up between August 2009 and February 2014, were enrolled in the study. Echocardiographic response to CRT was defined as "an increase of ≥ 5% in ejection fraction" and clinical response to CRT was defined as "an improvement ≥ 1 in New York Heart Association class without heart failure hospitalization after 6 months of CRT implantation."

RESULTS

At a mean follow-up of 9.2 ± 2.1 months, 142 patients (67%) were classified as responders to CRT. BiP-QRS duration was significantly longer among non-responders compared with responders (p = 0.036). More of the non-responders have notched in their BiP-QRS than responders (63% vs. 40%, p = 0.002). Median duration of notch was significantly higher among non-responders (80 ms vs. 67.5 ms, p = 0.041). Notch duration > 67.5 ms was associated with 2.8 times higher non-response to therapy (odds ratio: 2.8; 95% confidence interval: 1.075-7.588, p = 0.035).

CONCLUSIONS

Patients with notch duration greater than 67.5 ms are associated with poor response to CRT. Notch duration > 67.5 ms predicts non-response to therapy with 50.0% specificity and 72.1% sensitivity.

Significance of a fragmented QRS complex in patients with chronic total occlusion of coronary artery without prior myocardial infarction

Objective:

Fragmented QRS (fQRS) complexes that have numerous RSR´ patterns represent alteration of ventricular depolarization. We evaluated the relationship between fQRS and poor coronary collateral circulation and the diagnostic ability of fQRS for myocardial scar detection in patients with chronic total occlusion (CTO) without a history of myocardial infarction.

Methods:

The study population consisted of patients undergoing coronary angiography with a suspicion of CAD. Seventy-nine patients with one totally occluded major coronary artery were enrolled. Exclusion criteria were history of MI; recent acute coronary syndrome; pathologic Q wave on 12-lead ECG; cardiomyopathy or severe valvular disease; coronary artery bypass surgery or percutaneous coronary angioplasty. Collateral circulation was scored on the basis of Rentrop's classification. All patients were assessed by myocardial perfusion SPECT. Fragmented QRS was characterized as existence of an R´ or R wave or S wave notch in two adjacent leads related to the location of a major coronary artery region. Single and multiple logistic regression analyses were completed in the forward method.

Results:

Forty-nine patients had poor and 30 had well-developed collateral circulation. Fragmented QRS complexes were significantly higher in the poor collateral group (81% vs. 20%, p<0.001). Sensitivity, specificity, and the positive and negative predictive values of fQRS for myocardial scar identification were 89.4%, 87.5%, and 91.3% and 84.8%, respectively. The summed stress score and the summed rest score on SPECT were significantly higher in the poor collateral group than in the well-developed group (p<0.001) as well as in the fQRS group than the non-fQRS group (p<0.001). Logistic regression analysis revealed that the presence of fQRS was significantly and independently associated with poor collateral circulation and myocardial scar in patients with CTO.

Conclusion:

Fragmented QRS is independently related to poor coronary collateral circulation in patients with CTO without prior myocardial infarction. Notably, it can be a good predictor of myocardial scar rather than merely ischemia, with high diagnostic accuracy.

Ten advances defining sudden cardiac death

Recent advances in the field of sudden cardiac death (SCD) include the recognition that 50% of SCD occurs as initial presentation of any heart disease and that many of these individuals may have been considered to be low risk. The presenting dysrhythmia in patients with cardiac arrests has changed over time such that pulseless electrical activity and asystole is more frequently encountered as compared with ventricular tachyarrhythmias. While the use of implantable defibrillators has been a tremendous advance in patients at risk for ventricular tachyarrhythmias, the use of automatic external defibrillators and wearable defibrillators is a recent advance that allows for potential SCD prevention in more patients. Finally, the area of medical genetics is an evolving discipline, which may enable clinicians to better individualize therapy for patients with genetic predispositions to cardiac dysrhythmias.

QRS Fragmentation and QTc Duration Relate to Malignant Ventricular Tachyarrhythmias and Sudden Cardiac Death in Patients with Hypertrophic Cardiomyopathy

BACKGROUND

QRS fragmentation (fQRS) and prolonged QTc interval on surface ECG are prognostic in various cardiomyopathies other than hypertrophic cardiomyopathy (HCM). The association between fQRS and prolonged QTc duration with occurrence of ventricular tachyarrhythmias or sudden cardiac death (VTA/SCD) in patients with HCM was explored.

METHODS AND RESULTS

One hundred and ninety-five clinical HCM patients were studied. QTc duration was derived applying Bazett's formula; fQRS was defined as presence of various RSR' patterns, R or S notching and/or >1 additional R wave in any non-aVR lead in patients without pacing or (in)complete bundle branch block. The endpoints comprised SCD, ECG documented sustained VTA (tachycardia or fibrillation) or appropriate implantable cardioverter defibrillator (ICD) therapies (antitachycardia pacing [ATP] or shock) for VTA in ICD recipients (n = 58 [30%]). QT prolonging drugs recipients were excluded. After a median follow-up of 5.7 years (IQR 2.7-9.1), 26 (13%) patients experienced VTA or SCD. Patients with fQRS in ≥3 territories (inferior, lateral, septal, and/or anterior) (p = 0.004) or QTc ≥460 ms (p = 0.009) had worse cumulative survival free of VTA/SCD than patients with fQRS in <3 territories or QTc <460 ms. fQRS in ≥3 territories (ß 4.5, p = 0.020, 95%CI 1.41-14.1) and QTc ≥460 ms (ß 2.7, p = 0.037, 95%CI 1.12-6.33) were independently associated with VTA/SCD. Likelihood ratio test indicated assessment of fQRS and QTc on top of conventional SCD risk factors provides incremental predictive value for VTA/SCD (p = 0.035).

CONCLUSIONS

Both fQRS in ≥3 territories and QTc duration are associated with VTA/SCD in HCM patients, independently of and incremental to conventional SCD risk factors.

QRS fragmentation and sudden cardiac death in the obese and overweight

Background

Obesity has been associated with significantly greater risk of sudden cardiac death (SCD); however, identifying the obese patient at highest risk remains a challenge. We evaluated the association between QRS fragmentation on the 12‐lead electrocardiogram and SCD, in obese/overweight subjects.

Methods and Results

In the ongoing prospective, community‐based Oregon Sudden Unexpected Death Study (population approximately 1 million), we performed a case‐control analysis, comparing obese/overweight SCD victims with obese/overweight controls from the same geographic region. Archived ECGs prior and unrelated to the SCD event were used for cases and all ECG measurements were assessed in blinded fashion. Fragmentation was defined as the presence of RSR’ patterns and/or notching of the R/S wave in at least 2 contiguous leads. Analysis was limited to ECGs with QRS duration <120 ms. Overall prevalence of fragmentation was higher in cases (n=185; 64.9±13.8 years; 67.0% male) compared with controls (n=405; 64.9±11.0 years; 64.7% male) (34.6% versus 26.9%, P=0.06). Lateral fragmentation was significantly more frequent in cases (8.1% versus 2.5%; P<0. 01), with non‐significant differences in anterior and inferior territories. Fragmentation in multiple territories (≥2) was also more likely to be observed in cases (9.7% versus 4.9%, P=0.02). In multivariable analysis with consideration of established SCD risk factors, lateral fragmentation was significantly associated with SCD (OR 2.84; 95% CI 1.01 to 8.02; P=0.05).

Conclusion

QRS fragmentation, especially in the lateral territory is a potential risk marker for SCD independent of the ejection fraction, among obese/overweight subjects in the general population.

Fragmented QRS complex is a diagnostic tool in patients with left ventricular diastolic dysfunction

Fragmented QRS complex (fQRS) on 12-lead ECG is associated with myocardial fibrosis and ischemic scar. Interstitial fibrosis is one of the histological characteristics of left ventricular diastolic dysfunction (LVDD). However, the clinical importance of fQRS in patients with LVDD remains unclear. Here, we assessed the hypothesis that the presence of fQRS is associated with disease severity in patients with LVDD, and could be used as an additional parameter to differentiate patients with heart failure with preserved ejection fraction (HFpEF) from LVDD. We analyzed 12-lead ECG of 239 patients with LVDD. The patients were divided into two groups according to the presence or absence of fQRS; 88 patients had fQRS (fQRS group) and 151 patients did not have fQRS (non-fQRS group). The percentage of patients with heart failure in the fQRS group was significantly higher than that in the non-fQRS group. The levels of B-type natriuretic peptide (BNP) and high-sensitive troponin T were significantly higher in the fQRS group than those in the non-fQRS group. In univariate logistic regression analysis, fQRS was associated with the presence of heart failure in patients with LVDD. Multivariate logistic regression analysis identified fQRS and BNP as independent indicators for HFpEF. In conclusion, the presence of fQRS on the ECG could be used as an additional tool to differentiate HFpEF from LVDD.

Prognostic implications of intraventricular conduction delays in a general population: the Health 2000 Survey

AIMS

We examined the prognostic impact of eight different intraventricular conduction delays (IVCD) in the standard electrocardiogram (ECG) in a community cohort.

METHODS AND RESULTS

Data were collected from 6299 Finnish individuals. During a mean 8.2 years (interquartile range 8.1 to 8.3) of follow-up 640 subjects died (10.2%); 277 (4.4%) were cardiovascular deaths. For both sexes, all-cause and cardiovascular mortality was higher in subjects with IVCD than in those without. In Cox regression analysis after adjustment for age and gender, the hazard ratio for cardiovascular mortality for non-specific IVCD was 4.25 (95% confidence interval [CI] 1.95-9.26, P < 0.0001) and for left bundle branch block (LBBB) 2.11 (95% CI 1.31-3.41, P = 0.002). Right bundle branch block (RBBB) was not related to additional mortality, while incomplete RBBB (IRBBB) presented a hazard ratio of 2.24 (95% CI 1.064-4.77, P = 0.036).

CONCLUSIONS

In the general population, non-specific IVCD, LBBB, and IRBBB were associated with increased relative risk for all-cause and cardiovascular mortality. RBBB did not have an impact on cardiovascular mortality either in subjects with or without previous heart disease.

Fragmented QRS can predict severity of aortic stenosis

BACKGROUND

Fragmented QRS (fQRS) is an indicator of nonhomogeneous ventricular activity caused by myocardial fibrosis. Aortic stenosis (AS) is known to be a cause of myocardial fibrosis. We aimed to investigate the relationship of fQRS with severity of AS, echocardiographic, and electrocardiographic findings, and development of atrial fibrillation and manifest heart failure in AS patients.

METHODS

One hundred four patients with moderate and severe AS were recruited for the study. Patients with mitral or tricuspid stenosis, previous myocardial infarction, segmental wall motion abnormality or left ventricular ejection fraction (LVEF) below 50% and patients with complete-incomplete BBB and pacemaker rhythm were excluded.

RESULTS

Mean age of the patients was 69 ± 14.8 and 73.1% had fQRS. Patients with fQRS had lower LVEF, higher mean QRS duration, intrinsic deflection, Cornell voltage, Romhilt-Estes Score, systolic pulmonary artery pressure, mean and peak systolic transaortic gradients and left atrium diameter. Manifest heart failure was more frequent in patients with fQRS. In stepwise multivariate logistic regression analyze, manifest heart failure, peak systolic transaortic gradient, LVEF, intrinsic deflection, strain pattern and Cornell voltage were independently associated with fQRS. Strain pattern and fQRS were found as independent predictors of severe AS.

CONCLUSIONS

fQRS is independently associated with the severity of AS while traditional LVH criteria, except strain pattern, are not. fQRS may be better than traditional ECG criteria of LVH and echocardiographic LVH as an indicator of myocardial fibrosis in AS. Thus, fQRS may have a role in determining the severity and prognosis of AS.

Association of Fragmented QRS with Subclinical Left Ventricular Dysfunction in Patients with Obstructive Sleep Apnea

OBJECTIVE

We aimed to investigate whether fragmented QRS (fQRS) is associated with subclinical left ventricular (LV) dysfunction in patients with obstructive sleep apnea (OSA).

SUBJECTS AND METHODS

A total of 141 patients with OSA who had normal LV ejection fraction (LVEF) were included in the study. The fQRS was defined as the presence of an additional R wave, notching of R or S wave or the presence of fragmentation in 2 contiguous electrocardiography (ECG) leads. Subclinical LV dysfunction was defined as the presence of a tissue Doppler-derived Tei index of ≥ 0.5 in the absence of impaired LVEF (<50%) as assessed by transthoracic echocardiography.

RESULTS

Of the 141 patients, 71 (50.4%) had subclinical LV dysfunction. Overall, the prevalence of the fQRS was 61% (86/141). Patients with fQRS had significantly higher Tei indices than those without fQRS [median 0.66, interquartile range (IQR) 0.39 vs. median 0.40, IQR 0.15, p < 0.001]. The presence of fQRS on ECG predicted subclinical LV dysfunction in univariate logistic regression analysis [odds ratio (OR) 6.69, 95% confidence interval (CI) 3.10-14.43]. The association remained significant after adjusting for all potential confounders (OR 4.59, 95% CI 1.94-10.87).

CONCLUSION

fQRS on ECG was an independent predictor of subclinical LV dysfunction in patients with OSA. This simple tool might help to identify OSA patients who could be at risk for developing overt cardiac dysfunction.

Fragmented QRS predicts heart failure progression in patients with hypertrophic cardiomyopathy

BACKGROUND

Although fragmented QRS complex (frag-QRS) reflecting intra-ventricular conduction delay has been shown to be a prognostic marker for cardiac events, few data exist regarding the impact of frag-QRS on cardiac events in hypertrophic cardiomyopathy (HCM).

METHODS AND RESULTS

Ninety-four HCM patients (56 male; mean age, 58 ± 17 years) were retrospectively investigated. Frag-QRS was defined as the presence of various RsR' patterns in at least 2 contiguous ECG leads. Major arrhythmic events (MAE) were defined as sudden cardiac death, and combined sustained ventricular tachycardia/ventricular fibrillation. New-onset atrial fibrillation (AF) was diagnosed based on ECG during provisional or routine medical examination. Heart failure (HF) with hospitalization was defined as hospital admission due to subjective or objective symptoms. Frag-QRS was detected in 31 patients (33%).TNNI3 was the most frequent disease-causing gene. Median follow-up was 4.6 years. The 4-year cumulative survival rates of cardiac death, MAE, new-onset AF and HF with hospitalization were 97.6%, 94.6%, 87.5% and 89.3%, respectively. On multivariate analysis, frag-QRS was significantly associated with HF with hospitalization (adjusted hazard ratios [95% confidence intervals]: 5.4 [1.2-36], P=0.03). Moreover, HF-free survival was significantly lower in the frag-QRS (+) group compared to the frag-QRS (-) group (79.0% vs. 95.1%, P=0.03).

CONCLUSIONS

Frag-QRS is associated with HF with hospitalization in HCM patients who had a unique distribution of gene mutations.

Fragmented QRS for the prediction of sudden cardiac death: a meta-analysis

AIMS

Risk stratification of sudden cardiac death (SCD) is challenging. Fragmented QRS (fQRS) is proposed as a non-invasive electrocardiogram marker associated with mortality and SCD. Results from individual studies including small numbers of patients are discrepant. We therefore performed a meta-analysis of studies evaluating fQRS as a risk stratification tool to predict all-cause mortality and SCD.

METHODS AND RESULTS

Electronic databases and bibliographies were systematically searched (1996-2014). Twelve studies (5009 patients) recruiting patients with coronary artery disease or non-ischaemic cardiomyopathy met our inclusion criteria. Fragmented QRS was associated with an all-cause mortality relative risk of 1.71 (CI 1.02-2.85) and a relative risk of SCD of 2.20 (CI 1.05-4.62). Subgroup analysis demonstrated greater mortality and SCD risk in those with left ventricular ejection fraction >35% and SCD risk in those with QRS duration <120 ms.

CONCLUSION

Fragmented QRS is associated with all-cause mortality and the occurrence of SCD and may be suited as a marker of SCD risk. The incremental benefit of fQRS should be assessed in a randomized, prospective setting.

The role of fQRS in coronary artery disease. A meta-analysis of observational studies

BACKGROUND

Experimental and clinical studies have suggested that the presence of fragmented QRS complex (fQRS) is associated with various cardiovascular diseases. fQRS may predict major adverse cardiovascular events (MACE). The current meta-analysis was performed using clinical outcome studies to evaluate the role of fQRS in coronary artery disease (CAD).

METHODS

A systematic search of electronic databases (Cochrane, Medline, Embase and Pubmed) from their inception to April 2014 was performed. Data were extracted from applicable articles to evaluate the prognostic value of fQRS in CAD.

RESULTS

A total of 16 observational studies about fQRS and CAD (n = 3,997 patients) were identified. Compared with the non-fQRS group, MACE and mortality were significantly higher in the fQRS group -odds ratios (OR) 3.19, 95 % confidence interval (95 % CI) [2.3, 4.42], p < 0.00001; OR 2.24, 95 % CI [1.71, 2.94], p < 0.0001. Patients developed Q waves, anterior-wall myocardial infarction (MI), and low left ventricular ejection fraction (LVEF) more frequently in the fQRS group than in the non-fQRS group-OR 2.59, 95 % CI [1.76, 3.81], p < 0.00001; OR 2.43, 95 % CI [1.07, 5.52], p = 0.03; OR - 6.43, 95 % CI [- 9.11, - 3.74], p < 0.00001.

CONCLUSION

Based on current evidence, fQRS was associated with increased MACE, mortality, Q waves, anterior-wall MI, and decreased LVEF in CAD. These findings show that fQRS is a reliable marker in CAD.

The role of the fragmented QRS complexes on a routine 12-lead ECG in predicting non-responsiveness to cardiac resynchronization therapy

Objective:

Cardiac resynchronization therapy (CRT) is introduced as a promising therapeutic option in heart failure (HF) patients with ventricular dyssynchrony. The challenge, however, is identifying the patients who are suitable candidates for this procedure. Fragmented QRS (fQRS) is associated with subendocardial fibrosis and myocardial scars. In this study, we aimed to evaluate the role of fragmented QRS complex on a routine 12-lead ECG as a predictor of response to CRT.

Methods:

Sixty-five consecutive patients with HF who underwent CRT, were studied. Patients’ resting 12-lead ECGs were analyzed to find presence of fQRS by a cardiologist. Echocardiographic response to CRT was defined as ≥15% decrease in left ventricular end-systolic volume (LVESV) after CRT implantation. Response to CRT was compared between patients with and without fQRS.

Results:

The study group included 27 women (41.5%) and 38 men (58.5%) with a mean (±SD) age of 62±12 years. 27 patients (41.5%) had fQRS in their basal ECGs. Totally 46 patients (70.8%) responded to CRT in a way that the mean left ventricular ejection fraction (%) significantly increased, and left ventricular end diastolic volume (LVEDV) significantly decreased after CRT (p<0.001 and p=0.001 respectively). In multivariate logistic analysis, lack of fQRS was found to be a predictor of response to CRT (OR: 4.553, 95% CI: 1.345-15.418, p=0.015).

Conclusion:

We showed that the fQRS complex, as a sign of myocardial scar, predicts non-responsiveness to CRT. Therefore, fQRS may help selecting of CRT candidates.

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.

The Presence of Fragmented QRS on 12-Lead Electrocardiography in Patients with Coronary Artery Ectasia

Background and Objectives

Coronary artery ectasia (CAE) is an angiographic finding characterized by dilation of an arterial segment with a diameter at least 1.5 times that of its adjacent normal coronary artery. Fragmented QRS (fQRS) complexes are electrocardiographic signals which reflect altered ventricular conduction around regions of a myocardial scar and/or ischaemia. In the present study, we aimed to evaluate the presence of fQRS in patients with CAE.

Subjects and Methods

The study population included 100 patients with isolated CAE without coronary artery disease (CAD) and 80 angiographically normal controls. fQRS was defined as the presence of an additional R wave or notching of R or S wave or the presence of fragmentation in two contiguous leads corresponding to a major coronary artery territory.

Results

The two groups were similar in terms of age, sex, hypertension, dyslipidemia, and family history of CAD. The presence of fQRS was significantly (p<0.05) higher in the CAE group than that in the normal coronary artery group (29% vs. 6.2%, p=0.008). Isolated CAE were detected most commonly in the right coronary artery (61%), followed by left anterior descending artery (52%), left circumflex artery (36%), and left main artery (9%). Multivariate stepwise logistic regression analysis showed that CAE {odds ratio (OR) 1.412; 95% confidence interval (CI) 1.085-1.541; p=0.003} and diabetes (OR 1.310; 95% CI 1.025-1.482; p=0.041) were independently associated with fQRS.

Conclusion

The presence of fragmented QRS associated with increased risk for arrhythmias and cardiovascular mortality was significantly higher in patients with CAE than in patient with normal coronary artery. Further studies are needed to determine whether the presence of fragmented QRS is a possible new risk factor for patients with CAE.

Correlation between fragmented QRS and the short-term prognosis of patients with acute myocardial infarction

This study is aimed to investigate the clinical significance and the short-term prognostic value of fragmented QRS (fQRS) for patients with acute myocardial infarction (AMI). Three hundred patients with AMI were tested with retrospective analysis on the patients' clinical information, hospitalized treatment, fQRS onset time, location of lesions, and other relevant data, in order to assess the relationship between the presence of fQRS and its prognosis. The rates of malignant cardiac arrhythmia, left ventricular systolic dysfunction (LVSD), and mortality in the positive fQRS group were 13.6%, 29.2%, and 23.7%, respectively, with all showing a p value <0.05. For the ST segment elevation myocardial infarction (STEMI) subgroup, all the rates showed significant differences with a p value <0.01, while for the non-STEMI (NSTEMI) subgroup showed no significant differences. In patients with a positive fQRS, there were no differences in malignant cardiac arrhythmia between patients with and without percutaneous coronary intervention (PCI) (p>0.05). As for the LVSD and mortality, the p values between patients with and without PCI were 0.031 and 0.000, respectively, suggesting statistical significance. The results imply that AMI patients with positive fQRS especially for the patients with STEMI had higher rates of malignant cardiac arrhythmia, LVSD, and mortality than the non-fQRS group. Patients of AMI with positive fQRS, who underwent early revascularization, could lower the incidence of the cardiovascular event. In addition, the presence of fQRS could be used as an indication of early intervention treatment for patients.

Fragmented QRS complexes-a novel but underutilized electrocardiograhic marker of heart disease

The electrocardiogram is the mainstay approach for diagnosing a myocardial infarction (MI). The diagnosis of an old MI and the identification of myocardial scar via the electrocardiogram are difficult because there are no other specific signs for a non-Q-wave MI. In this article, we will review the fragmented QRS and its role in identifying myocardial scar and depolarization abnormalities in patients with coronary artery disease.

Fragmented ECG as a risk marker in cardiovascular diseases

Various noninvasive tests for risk stratification of sudden cardiac death (SCD) were studied, mostly in the context of structural heart disease such as coronary artery disease (CAD), cardiomyopathy and heart failure but have low positive predictive value for SCD. Fragmented QRS complexes (fQRS) on a 12-lead ECG is a marker of depolarization abnormality. fQRS include presence of various morphologies of the QRS wave with or without a Q wave and includes the presence of an additional R wave (R’) or notching in the nadir of the R’ (fragmentation) in two contiguous leads, corresponding to a major coronary artery territory. fQRS represents conduction delay from inhomogeneous activation of the ventricles due to myocardial scar. It has a high predictive value for myocardial scar and mortality in patients CAD. fQRS also predicts arrhythmic events and mortality in patients with implantable cardioverter defibrillator. It also signifies poor prognosis in patients with nonischemic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy and Brugada syndrome. However, fQRS is a nonspecific finding and its diagnostic prognostic should only be interpreted in the presence of pertinent clinical evidence and type of myocardial involvement (structural vs. structurally normal heart).

Regression of fragmented QRS complex: a marker of electrical reverse remodeling in cardiac resynchronization therapy

BACKGROUND

Fragmented QRS (fQRS) marks inhomogeneous activation and asynchronous cardiac contraction. It has been proved that cardiac resynchronization therapy (CRT) could reverse geometrical remodeling as well as correct electrical dyssynchrony. We aimed to investigate whether fQRS changed corresponding to the therapeutic response to CRT.

METHODS

Patients who underwent de novo CRT implantation previously and had ≥1 follow-up between August 2012 and September 2013 in our hospital were investigated. Intrinsic electrocardiogram was recorded and fQRS in any lead was calculated. Response to CRT was defined as absolute improvement in left ventricular ejection fraction by ≥10% or by improvement >1 New York Heart Association class and without heart failure hospitalization.

RESULTS

A total of 75 patients (48 male, mean ages, 61 ± 9 years) were included in this study. At a median follow-up of 13 months, 57 patients had response to CRT. Responders had narrowed QRS (from 167 ± 23 ms to 158 ± 19 ms, P = 0.003) and reduced fQRS post-CRT. Nonresponders had QRS prolonging (from 151 ± 26 ms to 168 ± 16 ms, P = 0.033) and increase in fQRS. Eleven of 12 patients with reduced fQRS were responders and 8 of 12 with increased fQRS were nonresponders. Both changes in QRS and fQRS correlated strongly with CRT response (r = 0.389, P = 0.001 and r = 0.403, P = 0.000, respectively). Reduction of fQRS in ≥1 leads had high specificity (95%) in association to responders, though in low sensitivity (19%).

CONCLUSIONS

The changes in fQRS associated with therapeutic response to CRT. Regression of fQRS could be a maker of electrical reverse remodeling following CRT.

Association between resolution of fragmented QRS and response to cardiac resynchronization therapy

BACKGROUND

Cardiac resynchronization therapy (CRT) has been recommended for patients with symptomatic heart failure and a wide QRS. Fragmented QRS (fQRS) on a 12-lead electrocardiography (ECG) has been shown to predict cardiac events. We aimed to investigate the relationship between resolution of fQRS and response to CRT.

METHODS

Sixty-seven consecutive patients (38 men, mean age 65 ± 11) with left bundle branch block and fQRS on ECG undergoing CRT were studied. The presence of fQRS was assessed using standardized criteria. Echocardiographic response to CRT was defined by a ≥15% reduction in left ventricular end-systolic volume (LVESV) and resolution of fQRS was defined as decrease in number of leads with fQRS on ECG at 6 months follow-up.

RESULTS

Thirty-nine patients (58%) had response to CRT. LVESV significantly decreased from 150 ± 64 to 100 ± 48 in responders (P = 0.001). There was not any significant decrease in nonresponders (LVESV; from 157 ± 70 to 153 ± 66, P = 0.45). The number of leads with fQRS was decreased from 4.4 ± 1.8 to 1.7 ± 1.6 in responder patients (P < 0.001). The number of leads with fQRS was not significantly changed in nonresponders. (4.2 ± 2.2 vs. 5.1 ± 2.4, P = 0.06). In multivariate analysis, significant associates of response to CRT was evaluated adjusting for etiology of cardiomyopathy, baseline QRS width, left ventricular ejection fraction, number of leads with fQRS and resolution of fQRS. Resolution of fQRS was the only predictor of response to CRT (OR 0.018, 95% CI, 0.004-0.083, P < 0.001).

CONCLUSIONS

After adjusting for potential confounders, resolution of fQRS, is associated with response to CRT.

Electrocardiographic predictors of sudden and non-sudden cardiac death in patients with ischemic cardiomyopathy

OBJECTIVE

This study evaluated the prognostic value of electrocardiogram (ECG)-based predictors in the primary prevention of sudden cardiac arrest (SCA) among ischemic cardiomyopathy patients with depressed left ventricular ejection fraction (LVEF ≤35%).

BACKGROUND

The prediction of cause-specific mortality in high-risk patients offers the potential for targeting specific therapies (i.e., implantable cardioverter-defibrillator [ICD]).

METHODS

Subjects were recruited from the Prediction of Arrhythmic Events with Positron Emission Tomography (PAREPET) study. Continuous Holter 12-lead ECG recordings were obtained at the start of study and used to compute 15 clinically-important ECG abnormalities (e.g., atrial fibrillation).

RESULTS

Among 197 patients (age 67 ± 11 years, 93% male, mean follow-up 4.1 years) enrolled, 30 (15%) were SCA cases and 35 (18%) cardiac non-sudden deaths (C/NS). In multivariate analysis, only heart-rate-corrected QT interval (QTc) predicted SCA (hazard ratio 2.9 [1.2-7.3]) and only depressed heart rate variability (HRV) predicted C/NS (hazard ratio 5.0 [1.5-17.1]) independent of demographic and clinical parameters.

CONCLUSIONS

Among patients with depressed LVEF, prolonged QTc suggests greater potential benefit from ICD therapy to prevent SCA; depressed HRV suggests potential benefit from bi-ventricular pacing to prevent C/NS.

Repolarization Parameters Are Associated With Mortality In Chagas Disease Patients In The United States

Objective

The goal of this study was to examine the association between ECG repolarization parameters and mortality in Chagas disease (CD) patients living in the United States.

Methods

CD patients with cardiomyopathy (CM) and bundle branch block (BBB) or BBB alone were compared to age- and sex-matched controls. QT interval, QT dispersion (QTd), T wave peak to T wave end duration (Tp-Te) and T wave peak to T wave end dispersion ((Tp-Te)d) were measured. Presence of fractionated QRS (fQRS) was also assessed. The main outcome measure was the association between ECG parameters and mortality or need for cardiac transplant.

Results

A total of 18 CM and 13 BBB CD patients were studied with 97% originating from Mexico or Central America. QTd (60.0±15.0 ms vs 43.5±9.8 ms, P=0.0002), Tp-Te (102.6±29.3 ms vs 77.1±11.0 ms, P=0.0002) and (Tp-Te)d (39.5±9.4 ms vs 22.7±7.6 ms, P<0.0001) were prolonged in CD CM patients compared to CM controls. Chagas CM patients had more fQRS then controls (84.2±0.10% vs 33.3±0.11%, p=0.0005). QTd (59.9±15.0 ms vs 29.5±6.9 ms, P=0.0001) and (Tp-Te)d (40.0±15.9 ms vs 18.5±5.4 ms, p<0.0001) were longer in the CD BBB group compared to BBB controls. Univariate analysis showed QTd (56.9±15.0 ms vs 46.5±17.3 ms, p=0.0412) and (Tp-Te)d (36.8±13.5 ms vs 28.5±13.3 ms, p=0.0395) were associated with death and/or need for cardiac transplant.

Conclusion

Our results indicate that P-max and PD are useful electrocardiographic markers for identifying the β-TM-high-risk patients for AF onset, even when the cardiac function is conserved.

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.

Fragmented QRS predicts the arrhythmic events in patients with heart failure undergoing ICD implantation for primary prophylaxis: more fragments more appropriate ICD shocks

BACKGROUND

Fragmented QRS complex (fQRS) is associated with cardiovascular outcomes in various patient populations. Although there were clinical studies investigating the association of fQRS with arrhythmic events in patients with systolic heart failure, the results were conflicting regarding the association of implantable cardioverter defibrillator (ICD) shocks and fQRS. In this study, we aimed to evaluate the association between the presence and extent of fQRS with appropriate ICD shocks and/or all-cause mortality.

METHODS

A total of 215 patients (age: 58.2 ± 11.6 years, 72.5 % male) with the diagnosis of left ventricular systolic heart failure in whom ICD had been implanted for primary prophylaxis were enrolled. Standard ECG evaluation revealed fQRS complex in 123 patients (57.2 %). The phenomenon of fQRS was defined as deflections at the beginning of the QRS complex, on top of the R wave, or in the nadir of the S wave similar to the definition in CAD.

RESULTS

At mean 23.5 ± 12.1 months follow-up, all-cause mortality was observed in 45 (20.9 %) patients and 111 (51.6 %) patients experienced appropriate ICD shocks. Median number of ECG leads with fQRS were higher in patients with appropriate ICD shocks (3 [2-6] vs 1 [0-2], P < 0.001, respectively). The presence of fQRS (HR: 6.64, 95 % CI: 3.54-12.4, P < 0.001) and the number of leads with fQRS (HR: 1.35, 95% CI: 1.22-1.67) were found as independent predictors of appropriate ICD shocks. Additionally, there was a negative correlation between left ventricular ejection fraction and the number of leads with fQRS (r = -0.434, P < 0.001). Rates of all-cause mortality did not differ between the fQRS(+) (29 [24 % ]) and fQRS(-) (16 [17 % ]) groups (P = 0.27).

CONCLUSION

Our findings suggest that the presence and extent of fQRS complex on standard 12-lead ECG predicts appropriate ICD shocks in patients with left ventricular systolic heart failure who underwent ICD implantation for primary prophylaxis.

Relationship between fragmented QRS complex and left ventricular systolic and diastolic function in kidney transplant patients

BACKGROUND

Kidney transplant is a most important replacement therapy. It reduces cardiovascular mortality and morbidity but does not fully correct impairments in cardiac function. Fragmented QRS (fQRS) complex includes various RSR' patterns with different QRS complex morphologies on electrocardiograms.

OBJECTIVE

To analyze fQRS frequency and the relationship between fQRS and left ventricular function in kidney transplant patients.

METHOD

-After demographic data on 39 kidney transplant patients were recorded and biochemical parameters were investigated, electrocardiograms were evaluated for the presence of fQRS. Left ventricular ejection fraction, mitral annular plane systolic excursion, peak early diastolic mitral annular velocities, late diastolic mitral annular velocities, and systolic mitral annular velocity were analyzed.

RESULTS

Fragmented QRS was detected in 16 patients. A history of hypertension was associated with the presence of fQRS. Patients with fQRS had significantly lower systolic and peak early diastolic mitral annular velocities, mitral annular plane systolic excursion, and left ventricular ejection fraction than did patients without fQRS (P= .03, .01, <.001, and .03, respectively).

CONCLUSION

Detection of fQRS on electrocardiograms may be useful in predicting systolic and diastolic dysfunction of the left ventricle in kidney transplant patients.

The relationship between fragmentation on electrocardiography and in-hospital prognosis of patients with acute myocardial infarction

Background

In patients with acute ST elevation myocardial infarction (STEMI), QRS fragmentation was determined as one of the indicators of mortality and morbidity. The development of fragmented QRS (fQRS) is related to defects in the ventricular conduction system and is linked to myocardial scar and fibrosis.

Material/Methods

We prospectively enrolled 355 consecutive patients hospitalized in the coronary intensive care unit of our hospital with STEMI between the years 2010 and 2012 and their electrocardiographic features and the frequency of in-hospital cardiac events were evaluated.

Results

There were 217 cases in the fQRS group and 118 cases in the control group. QRS fragmentation was found to be a predictor for major cardiac events. In the fragmented QRS group, the frequency of in-hospital major cardiac events (MACE) and death were higher (MACE p<0.001; death p<0.003). In the fragmented QRS group, the cardiac enzymes (Troponin-I, CK-MB) were significantly higher than in the control group (p<0.001). In subgroup analyses, apart from the presence of fragmentation, the presence of more than 1 type of fragmentation and the number of fragmented deviations were also found to be related with MACE. A significant negative correlation was observed with the ejection fraction and, in particular, the number of fragmented deviations.

Conclusions

Fragmented QRS has emerged as a practical and easily identifiable diagnostic tool for predicting in-hospital cardiac events in acute coronary syndromes. Patients who present with a fragmented QRS demonstrate increased rates of major cardiac events, death risk, and low ejection fraction. In patients with STEMI, the presence of fQRS on the ECG and number of fQRS derivations are a significant predictor of in-hospital major cardiac events.