Single Derivation Fragmented QRS Can Predict Poor Prognosis in Successfully Revascularized Acute STEMI Patients

The association between QTc, QTd, TPE, and fragmented QRS before and after PPCI with hospital mortality in STEMI patients

INTRODUCTION

ST-elevation myocardial infarction (STEMI) is known to be associated with significant arrhythmia and consequent mortality. QT prolongation is a risk factor for arrhythmia in STEMI patients who underwent primary percutaneous coronary intervention (PPCI). The aim of this investigation was to evaluate the association of corrected QT interval (QTc), QT dispersion (QTd), T-wave peak to end (TPE), and fragmented QRS with mortality in these patients.

METHODS

Eligible patients with the characteristic symptoms of STEMI who underwent PPCI were included. QTc, QTd, TPE, and fragmented QRS were measured before and after the PPCI. These predictors were compared between patients who died during hospitalization and discharged patients.

RESULTS

After coronary angiography, 10 patients (4%) died during the hospitalization after PPCI. Comparing the non-survivers and discharged patients in terms of arrhythmia predictors showed that the mean QT dispersion and TPE before intervention were significantly higher in the non-survivors. Also, the number of patients who experienced fragmented QRS both before and after the intervention was significantly higher in the non-survivors.

CONCLUSION

These data suggested that evaluating such arrhythmia predictors, especially before PPCI, could be used as a predictor of mortality in STEMI patients who underwent PPCI.

Relationship between Fragmented QRS and Microvascular Dysfunction in Masked Hypertension

Aim

The aim of this study was to investigate the presence of fQRS and its association with subclinical systolic and microvascular dysfunction in patients with masked hypertension (MH).

Methods

The study population consisted of 95 (mean age 48.9 ± 11.3, 61% males) subjects with MH and 80 age- and gender-matched healthy individuals who served as a control group. Coronary flow reserve (CFR) using transthoracic echocardiography and for left ventricular global longitudinal strain (LVGLS) using speckle-tracking strain imaging were performed. Patients with MH were stratified into two groups according to the presence of fQRS on surface electrocardiogram.

Results

Fragmented QRS was more common among MH patients compared with controls (38.9% vs. 6.25%, p < 0.003). CFR was significantly lower in patients with fQRS compared with those without fQRS and controls (p < 0.001). Likewise, LVGLS values were lower in MH patients with fQRS (p < 0.001) compared with subjects without fQRS and controls. Fragmented fQRS was significantly correlated with systolic blood pressure, CFR, and LVGLS. Multivariate analysis showed that the presence of fQRS, number of leads, and CFR were independent predictors of subclinical systolic dysfunction. With ROC cure analysis, number of leads with fQRS ≥4 was the optimal value for predicting the presence of subclinical systolic dysfunction in subjects with MH.

Conclusions

Fragmented QRS is more frequent among subjects with MH compared with controls. The presence of fQRS is related with pronounced subclinical left ventricular systolic dysfunction. Furthermore, CFR was significantly reduced in subjects with MH, a finding supposed that microvascular dysfunction to be a mechanistic link.

Characteristics of Circadian Blood Pressure Pattern of Hypertensive Patients According to Localization of Fragmented QRS on Electrocardiography

INTRODUCTION

A narrow fragmented QRS complex (fQRS) indicates myocardial fibrosis and hypertensive cardiomyopathy in hypertensive patients. However, no study has investigated the importance of localization of fQRS on electrocardiography (ECG) in these subjects.

AIM

To investigate the association between circadian blood pressure (BP) pattern and localization of fQRS on ECG.

METHODS

A total of 291 hypertensive patients who had fQRS in anterior or inferior leads were included into the study. Patients were divided into two groups according to localization of fQRS in inferior or anterior leads. All patients underwent a 24-h ambulatory blood pressure monitoring for detailed evaluation of circadian BP pattern. The association between localization of fQRS and non-dipping was investigated.

RESULTS

Among study population, 182 (62.5%) patients had fQRS in inferior leads and 109 (37.5%) patients had fQRS in anterior leads. The frequency of patients with non-dipping BP pattern was significantly higher in patients with fQRS in anterior leads compared to patients with fQRS in inferior leads (47.7% vs 24.1%, p < 0.001). Moreover, the frequency of fQRS in anterior leads was significantly higher in non-dippers compared to dippers (64.6% vs. 24.1%, p < 0.001). Furthermore, in multivariate analysis, presence of fQRS in anterior leads was found to be an independent predictor of non-dipping BP pattern in hypertensive patients (OR: 1.748, 95% CI 1.362-2.446, p < 0.001).

CONCLUSIONS

Presence of fQRS in anterior leads is significantly associated with non-dipping BP pattern in hypertensive patients. Therefore, localization of fQRS on ECG may provide useful information regarding further risk assessment of hypertensive subjects.

The Predictive Value of Fragmented QRS for Cardiovascular Events in Acute Myocardial Infarction: A Systematic Review and Meta-Analysis

Objective: Fragmented QRS (fQRS) have been reported as a predictor of major adverse cardiac events (MACE) and mortality in several studies on cardiovascular disease. However, most studies have yielded discrepant results. This study aimed to explore the correlation between fQRS and cardiovascular events in patients with acute myocardial infarction (AMI) during their hospital stay and follow-up period, and the predictive value of fQRS in the prognosis of AMI. Methods: We searched for relevant studies in four databases, Medline, Embase, PubMed, and the Cochrane Library from January 2010 to March 2020. Our initial search yielded 585 articles. Of these, we screened 19 studies, and finally included a total of 6,914 patients in this analysis, comparing death events or MACE in AMI patients with or without fQRS. Results: Fragmented QRS was significantly associated with a higher risk of in-hospital mortality (OR, 3.97; 95% CI, 2.45-6.44; p < 0.00001), long-term mortality (OR, 2.93; 95% CI, 1.76-4.88; p < 0.0001), in-hospital MACE (OR, 2.48; 95% CI, 1.62-3.80; p < 0.0001), and long-term MACE (OR, 3.81; 95% CI, 2.21-6.57; p < 0.00001). In particular, it demonstrated a higher predictive value for in-hospital cardiovascular mortality and long-term all-cause mortality in AMI patients and in-hospital mortality in patients with ST-segment elevation myocardial infarction (STEMI). Moreover, fQRS was also associated with an increased risk of ventricular arrhythmias (OR, 2.76; 95% CI, 1.72-4.43; p < 0.0001) and heart failure (OR, 1.65; 95% CI, 1.02-2.66; p = 0.04). Fragmented QRS was negatively associated with left ventricular ejection function (LVEF) (MD, -5.47; CI, [-7.03, -3.91]; p < 0.00001) and positively associated with a high incidence of coronary artery triple vessel lesions (OR, 2.14; 95% CI, 1.31-3.51; p = 0.002) in AMI patients. Conclusion: Fragmented QRS is significantly associated with in-hospital and long-term mortality and MACE in patients with AMI, as well as ventricular arrhythmias and heart failure. Furthermore, it may be a marker of mortality and MACE risk. Moreover, fQRS also indicates a reduced LVEF and a high incidence of coronary artery triple vessel lesions in AMI patients. Meta-analysis Registration: https://www.crd.york.ac.uk/prospero; ID: CRD42020171668.

Fragmented QRS as a Marker of Myocardial Fibrosis in Hypertension: a Systematic Review

PURPOSE OF REVIEW

Hypertension cause damage in cardiac structure and induce pathological myocardial fibrosis that leads to hypertensive cardiomyopathy. A narrow fragmented QRS complex (fQRS) is associated with myocardial fibrosis and scar tissue in various cardiovascular diseases. It is also associated with myocardial fibrosis in hypertensive patients even in the absence of any structural heart diseases. This article aimed to demonstrate importance and usefulness of fQRS in hypertensive patients.

RECENT FINDINGS

Current evidence suggest that the frequency of fQRS is significantly higher in hypertensive patients compared to normotensives. Also, fQRS seems to be a predictor of left ventricular hypertrophy, increased systolic blood pressure, non-dipping, deterioration of the left ventricular geometry, and worse systolic and diastolic functions in hypertensive patients. As a simple and easy detectable electrocardiographic finding, fQRS may indicate myocardial fibrosis, uncontrolled blood pressure, and deteriorated cardiac structure in hypertensive patients even in the absence of other structural heart diseases, and may also be useful to predict high-risk hypertensives.

Association Between Non-Dipping and Fragmented QRS Complexes in Prehypertensive Patients

Background

Fragmented QRS (fQRS) is a sign of adverse cardiovascular events in various cardiovascular diseases. It is also associated with increased blood pressure and non-dipping in hypertensive patients. However, no study has investigated the importance of fQRS in prehypertensive patients.

Objectives

The aim of our study is to investigate the relationship between fQRS and non-dipper status in prehypertensive patients.

Methods

Two hundred and sixteen eligible, newly diagnosed prehypertensive patients who underwent 24-hour ambulatory blood pressure monitoring (ABPM) for further evaluation of blood pressure between June 2015 and July 2016 were included into the study. Patients were divided into three groups according to ABPM results: normotensives, dipper prehypertensives, and non-dipper prehypertensives. Groups were compared regarding presence of fQRS on electrocardiography. Additionally, multinomial logistic regression analysis was used to determine the relationship between fQRS and blood pressure pattern in prehypertensive patients.

Results

According to ABPM recordings, 61 patients had normotensive blood pressure pattern (systolic blood pressure < 120 mmHg and diastolic blood pressure < 80 mmHg). Of the remaining 155 prehypertensive patients, 83 were dippers and 72 were non-dippers. Non-dipper prehypertensives had a significantly higher frequency of fQRS compared to normotensives (p = 0.048). Furthermore, multinomial logistic regression analysis revealed that fQRS is an independent predictor of non-dipping blood pressure pattern in prehypertensive patients (p = 0.017, OR: 4.071, 95% CI: 1.281-12.936).

Conclusions

We found that fQRS is a predictor of non-dipping in prehypertensives. As a marker of fibrosis and higher fibrotic burden within myocardium, fQRS may be useful in identifying high-risk prehypertensive patients before the development of hypertension.

Fragmented QRS and mortality in patients undergoing percutaneous intervention for ST-elevation myocardial infarction: Systematic review and meta-analysis

BACKGROUND

Fragmented QRS reflects disturbances in the myocardium predisposing the heart to ventricular tachyarrhythmias. Recent studies suggest that fragmented QRS (fQRS) is associated with mortality in ST-elevation myocardial infarction (STEMI) patients who underwent percutaneous coronary intervention (PCI). However, a systematic review and meta-analysis of the literature has not been done. We assessed the association between fQRS and overall mortality in STEMI patients who subsequently underwent PCI by a systematic review and meta-analysis.

METHODS

We comprehensively searched the databases of MEDLINE and EMBASE from inception to September 2017. Studies included in our analysis were published cohort (prospective or retrospective) and case-control studies that compared overall mortality among STEMI patient with and without fQRS who underwent PCI. Data from each study were combined using the random-effects, generic inverse variance method of DerSimonian, and Laird to calculate risk ratios and 95% confidence intervals.

RESULTS

Six studies from 2014 to 2017 were included in this meta-analysis involving 2,516 subjects with STEMI who underwent PCI (888 fQRS and 1,628 non-fQRS). Fragmented QRS was associated with overall mortality in STEMI patients who underwent PCI (pooled risk ratio = 3.87; 95% CI 1.96-7.66, I²  = 43%).

CONCLUSION

Fragmented QRS was associated with increased overall mortality up to threefold. Our study suggests that fQRS could be an important tool for risk assessment in STEMI patients who underwent PCI.

Combining fragmented QRS and TIMI score for predicting in-hospital short-term prognosis after acute myocardial infarction

Acute myocardial infarction (AMI) has a high mortality rate and poor prognosis for patients. The primary causes of death are arrhythmia and heart failure. For patients admitted because of myocardial infarction, various risk evaluations are initiated to foresee possible complications. The thrombolysis in myocardial infarction (TIMI) risk score, which can be used to predict the prognosis and the need for revascularisation, is the most convenient and commonly used system, but is inadequate for AMI patients on admittance. Fragmented QRS (fQRS) has been shown to be a valuable electrocardiographic (ECG) index for predicting the prognosis of patients with coronary heart disease. Also, fQRS is considered to predict an increased likelihood of a poor outcome and mortality in patients with coronary artery disease (CAD), even for some successfully revascularized AMI patients. So what would happen if fQRS and the TIMI risk score were combined? This study focused on the investigation of the short-term prognostic value of fQRS combined with the TIMI risk score for patients with AMI.