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

Toward Enabling Cardiac Digital Twins of Myocardial Infarction Using Deep Computational Models for Inverse Inference

Cardiac digital twins (CDTs) have the potential to offer individualized evaluation of cardiac function in a non-invasive manner, making them a promising approach for personalized diagnosis and treatment planning of myocardial infarction (MI). The inference of accurate myocardial tissue properties is crucial in creating a reliable CDT of MI. In this work, we investigate the feasibility of inferring myocardial tissue properties from the electrocardiogram (ECG) within a CDT platform. The platform integrates multi-modal data, such as cardiac MRI and ECG, to enhance the accuracy and reliability of the inferred tissue properties. We perform a sensitivity analysis based on computer simulations, systematically exploring the effects of infarct location, size, degree of transmurality, and electrical activity alteration on the simulated QRS complex of ECG, to establish the limits of the approach. We subsequently present a novel deep computational model, comprising a dual-branch variational autoencoder and an inference model, to infer infarct location and distribution from the simulated QRS. The proposed model achieves mean Dice scores of 0.457 ±0.317 and 0.302 ±0.273 for the inference of left ventricle scars and border zone, respectively. The sensitivity analysis enhances our understanding of the complex relationship between infarct characteristics and electrophysiological features. The in silico experimental results show that the model can effectively capture the relationship for the inverse inference, with promising potential for clinical application in the future. The code is available at https://github.com/lileitech/MI_inverse_inference.

Relationship between NT-proBNP levels and existing/de novo QRS fragmentation in patients with myocardial infarction

Aim: to assess the evolution of fragmented QRS (fQRS) and NT-proBNP levels during myocardial infarction (MI).Methods: Among 511 patients, 205 (40.1%) had fQRS, with 54 (26.3%) developing de novo fragmentation during hospitalization.Results: NT-proBNP levels were significantly higher in the fQRS+ group compared with the fQRS- group (1555 vs. 796 pg/ml, p < 0.001). NT-proBNP levels were higher in patients with de novo fragmentation than in those without (2852 vs. 1370 pg/ml, p = 0.011). The incidence of major adverse cardiovascular events was notably higher in fQRS+ patients compared with fQRS- patients (p = 0.001).Conclusion: In acute MI, there was a significant association between fQRS and NT-proBNP levels, with higher NT-proBNP levels observed in those with de novo fQRS compared with those without.

Fragmented QRS as a Predictor of Cardiovascular Events in Patients with Type 2 Diabetes Mellitus: A 36-Month Follow-Up Data

BACKGROUND

Major cardiovascular events (MACE) are more common in type 2 diabetes mellitus (T2DM) patients, and early diagnosis can prevent significant morbidity and mortality. The aim of this study was to investigate the predictiveness of fragmented QRS (fQRS) showing MACE in T2DM patients.

METHODS

A total of 227 T2DM patients (mean age 52, 51% male) without any cardiovascular disease who came to the cardiology outpatient clinic between March 01 and July 31, 2019, were included in the study. The patients were divided into 2 groups according to fQRS on electrocardiography (ECG), and 36 months of follow-up was done. The development of acute coronary syndrome, coronary revascularization, and cerebrovascular accident were accepted as MACE.

RESULTS

More MACE was seen in the group with fQRS on ECG (P =.026). Although there were more fQRS in patients with proteinuria, it was not statistically significant (P =.069). More myocardial infarcts (7.9%) and more cerebrovascular events (6.3%) were seen in the group with fQRS. While revascularization was performed on 3 patients in the fQRS group, revascularization was not performed on the patients in the non-fqrs group. In multiple Cox regression analysis, fQRS showed an independent predictor of MACE [P =.025, hazard ratio = 2.42 (1.117-5.221)], more MACE was seen in the fQRS (+) group in the kaplan-meier analysis (P =.022).

CONCLUSION

More MACE was seen in the fQRS group in T2DM patients without a previous history of cardiovascular events. Fragmented QRS was found to be an independent predictor in showing MACE. Care should be taken in terms of MACE development in T2DM patients with fQRS.

Fragmented QRS, a strong predictor of mortality and major arrhythmic events in patients with nonischemic cardiomyopathy: A systematic review and meta-analysis

Background and Aims

Fragmented QRS (fQRS), which is associated with rhythm disturbances, can predispose the heart to fatal ventricular arrhythmias. Recently, accumulating studies indicates that fQRS is associated with poor prognosis in various types of cardiomyopathies. Therefore, we assessed the association between fQRS with all-cause mortality and major arrhythmic events (MAEs) in patients with nonischemic cardiomyopathy, in this systematic review and meta-analysis study.

Methods

We performed a comprehensive search in databases of PubMed/Medline, EMBASE, and Web of Science from the beginning to December 31, 2022. Published observational studies (cohorts, case-control, or analytical cross-sectional studies) were included that report the prognostic value of fQRS in patients with different types of nonischemic cardiomyopathies for MAEs (sudden cardiac death, sudden cardiac arrest, sustained ventricular tachycardia [VT], ventricular fibrillation [VF], and appropriate shock) and all-cause mortality. We pooled risk ratios (RRs) through raw data and adjusted hazard ratios (aHRs) using "Comprehensive Meta-Analysis" software, Version 2.0.

Results

Nineteen cohort and three analytical cross-sectional studies were included in this meta-analysis involving a total of 4318 subjects with nonischemic cardiomyopathy (1279 with fQRS and 3039 without fQRS). FQRS was significantly associated with an increased risk of all-cause mortality in patients with nonischemic cardiomyopathy (pooled RR: 1.920; 95% confidence interval [CI]: 1.388-2.656, p < 0.0001/pooled HR: 1.729; 95% CI: 1.327-2.251, p < 0.0001). Also, the risk of developing MAEs in the presence of fQRS was significantly increased (pooled RR: 2.041; 95% CI: 1.644-2.533, p < 0.0001/pooled HR: 3.626; 95% CI: 2.119-6.204, p < 0.0001). In the subgroup analysis, the strongest association between fQRS presence and increased MAEs was observed in patients with hypertrophic cardiomyopathy (HCM) (pooled RR: 3.44; 95% CI: 2.07-5.71, p < 0.0001/pooled HR: 3.21; 95% CI: 2.04-5.06, p < 0.0001).

Conclusion

Fragmented QRS could be a prognostic marker for all-cause mortality and MAEs in patients with various types of nonischemic cardiomyopathies, particularly HCM.

Increasing averaging beats improves the test accuracy on Holter-based late potentials in patients with myocardial infarction

BACKGROUND

The prevalence of Holter-based late potentials (H-LPs) in cases of fatal cardiac events has increased. Although the noise level of H-LP is higher than that of conventional real-time late potential (LP) recording, a procedure to reduce the noise severity in H-LP by increasing the averaging beats has not been investigated.

METHODS

We enrolled 104 patients with post-myocardial infarction (MI) and 86 control participants. Among the patients, 30 reported sustained ventricular tachycardia (VT), and the remaining 74 had unrecorded VT. H-LPs were measured twice in all groups to evaluate the efficacy of increasing the averaging beats for H-LPs. Thereafter, the average of LP was calculated at 250 (default setting), 300, 400, 500, 600, 700, and 800 beats.

RESULTS

Across all three groups (MI-VT group, MI non-VT group, and control group), the noise levels significantly decreased in consonance with the increase in averaging beats. In the MI-VT group, the H-LP positive rate considerably increased with the increase in the averaging beats from 250 to 800 both at night and daytime. In the MI-VT group, the LP parameters significantly deteriorated, which led to a positive judgment corresponding to the increment of the averaged night and day beats. The H-LP positive rates were unchanged in the MI non-VT and control groups, while the LP parameters remained consistent, despite the increased averaging beats in the MI non-VT and control groups.

CONCLUSION

Increasing the calculated averaging beats in H-LPs can improve the sensitivity of predicting fatal cardiac events in patients with MI.

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.

Fragmented QRS as a risk marker for the occurrence of ventricular fibrillation in patients with variant angina

BACKGROUND

Variant angina (VA) is caused by reversible coronary artery spasm, which is characterized by chest pain with ST-segment elevations on standard 12-lead electrocardiogram (ECG) at rest. Ventricular fibrillation (VF) is often caused by VA attack, but the risk stratification is not well understood. The purpose of this study was to evaluate the impact of fragmented QRS (fQRS) on VF occurrence in VA patients.

METHODS

Ninety-four patients who showed ST elevation on 12-lead ECGs with total or nearly total occlusion in response to coronary spasm provocation test were enrolled. Among them, 16 patients had documented VF before hospital admission (n = 12) or experienced VF during provocation test (n = 4) (VF occurrence group). The fQRS was defined as the presence of spikes within the QRS complex of two or more consecutive leads.

RESULTS

The prevalence of fQRS was more often observed in the VF occurrence group than in the non-VF occurrence group (63% [10/16] vs. 27% [21/78], p = 0.009). Univariate analyses revealed that age, history of syncope, QTc, and the presence of fQRS were associated with VF occurrence (p = 0.004, 0.005, 0.029, and 0.008, respectively). Furthermore, upon multivariate analyses using those risk factors, age, QTc, and fQRS predicted VF occurrence independently (p = 0.007, 0.041, and 0.014, respectively).

CONCLUSIONS

The present study demonstrated that fQRS in VA patients is a risk factor for VF. The fQRS may be a useful factor for the risk stratification of VF occurrence in VA patients.

Electrocardiographic findings in true acute left main coronary total occlusion a subanalisys from ATOLMA registry

INTRODUCTION

Acute total occlusion of the left main coronary artery (ATOLMA) usually leads to a catastrophic presentation. Prediction of ATOLMA by electrocardiogram (ECG) may contribute to early detection and reperfusion. Limited data have been reported previously. This study aims to identify the admission 12‑leads ECG features that can predict the presence of ATOLMA and in-Hospital mortality in these patients.

METHODS

The admission ECGs findings in 24 patients from the previously reported ATOLMA multicenter registry were compared to the ECGs findings in 15 patients with an acute subtotal occlusion of the left main (ASOLMA) and to 15 patients with anterior ST-elevation myocardial infarction of the proximal left anterior descending (LADp-STEMI).

RESULTS

Some ECG features at presentation can predict an ATOLMA: QRS left axis deviation (-61.17 ± 9 degrees); ST-segment elevation in aVL (1.9 ± 0.65 mm); absence of ST-segment elevation in V1 (0.0 ± 0.6 mm); bifascicular block (58%); fragmented QRS (62.5%); prolongation of QTc interval (465 ± 19 ms) and of QRS interval (136 ± 12 mm). The multivariate analysis found that the independent predictors to distinguish ATOLMA from ASOLMA were aVL ST-segment deviation (OR 5.6(95% CI 1.5-21), p = 0.01) and absence of V1 ST-segment elevation (OR 27(95% CI 1.4-52), p = 0.01); and from LADp-STEMI was QRS width (OR 1.1(95% CI 1.02-1.2), p = 0.02). Fragmented QRS was the only independent predictor of in-hospital mortality in ATOLMA (OR 0.125(95% CI 0.01-0.81), p = 0.03).

CONCLUSIONS

aVL ST-segment elevation, the absence of V1 ST-segment elevation, left axis deviation, the presence of bifascicular block, and prolongation of QRS and QTc interval are predictors of ATOLMA. Fragmented QRS predicts in-hospital mortality in ATOLMA.