Localization of myocardial scar in patients with cardiomyopathy and left bundle branch block using electrocardiographic Selvester QRS scoring

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.

Value of q waves in lateral and left precordial leads in patients with left bundle branch block to predict the response to cardiac resynchronization therapy

BACKGROUND

The cardiac resynchronization therapy (CRT) non-response rate can reach 30% in heart failure (HF) patients with left bundle branch block (LBBB). This study aimed to evaluate the value of baseline q waves in leads I, V5, or V6 in predicting response to CRT in patients with HF and LBBB.

METHODS

Patients with HF (left ventricular ejection fraction ≤35%) and LBBB receiving CRT implantation were retrospectively enrolled. Baseline characteristics and electrocardiogram parameters, including lateral and left precordial q waves were evaluated. Non-response to CRT was defined as the improvement of left ventricular ejection fraction (LVEF) < 5% at a 6-month follow-up.

RESULTS

A total of 132 patients (mean age 63.0 ± 10.4 years, 94 [71.2%] male) were included. Among them, 32 patients with q waves in leads I, V5, or V6 were classified into the qLBBB (+) group, and the rest without q waves in these leads were defined as the qLBBB (-) group. The CRT non-response rate in the qLBBB (+) group was markedly higher than that in the qLBBB (-) group (68.8% vs. 33.3%, p < .001). Multivariable logistic regression analysis revealed that the presence of baseline q waves in leads I, V5, or V6 remained significantly associated with a higher rate of CRT non-response in patients with HF and LBBB (odds ratio: 4.8, 95% confidence interval: 1.5-15.0, p = .007).

CONCLUSION

Any q wave in leads I, V5, or V6 was an independent predictive factor for CRT non-response in patients with HF and LBBB.

Relationship between Selvester ECG Score and Cardiovascular Outcomes in Patients with Non-ST Elevation Myocardial Infarction

BACKGROUND

Early risk stratification plays a crucial role in the treatment of non-ST-elevation myocardial infarction (NSTEMI). Selvester score is an electrocardiography (ECG)-based method for estimating infarcted myocardial mass, however it has not been studied in NSTEMI before. In this study, we aimed to investigate the relationship between Selvester score and cardiovascular outcomes in a 1-year follow-up period in NSTEMI patients.

METHODS

One hundred and forty-three consecutive patients with NSTEMI were analyzed. TIMI and GRACE risk scores were calculated accordingly. Selvester score was calculated on surface ECG as reported in prior studies. Syntax score was calculated using an online calculator. The study population was divided into two groups based on a cut-off value from receiver operating characteristic curve analysis for the discriminative ability of Selvester score for mortality: low score (≤ 4), and high score (> 4) groups.

RESULTS

Age was higher, left ventricle ejection fraction and high-density lipoprotein-cholesterol levels were significantly lower, and TIMI, GRACE and SYNTAX scores were significantly higher in the high Selvester score group. In multivariate Cox regression analysis, ejection fraction [hazard ratio (HR): 0.926, 95% confidence interval (CI): 0.883-0.971, p = 0.002] and Selvester score > 4 (HR: 3.335, 95% CI: 1.306-8.503, p = 0.012) were found to be independent predictors of adverse events after 1 year of follow-up.

CONCLUSIONS

Selvester score is a fast and feasible method that has prognostic value for mortality and other major adverse outcomes in low and intermediate risk NSTEMI patients treated with urgent percutaneous coronary intervention for 12 months.

Myocardial Scar on Surface ECG: Selvester Score, but Not Fragmentation, Predicts Response to CRT

Purpose

Myocardial scar is directly related to the response to CRT after implantation. The extent of myocardial scar can be detected not only by cardiac magnetic resonance but also by two electrocardiographic scores: fragmented QRS (fQRS) and Selvester score (SSc). The aim of our study is to compare the role of baseline SSc and fQRS in predicting response to CRT in a cohort of heart failure patients with true left bundle branch block (LBBB). As a secondary endpoint, we assessed the association of both scores with overall and cardiac mortality, heart failure hospitalizations, ventricular arrhythmias requiring ICD intervention, and major adverse cardiovascular event (MACE).

Methods

We evaluated fQRS and SSc of 178 consecutive HF patients with severe systolic dysfunction (LVEF ≤ 35%), NYHA class II-III despite optimal medical treatment, and true-LBBB. Response to CRT was defined as the improvement of LVEF of at least 10% or as the reduction of LVESV of at least 15% at a 6-month follow-up. Each endpoint was related to fQRS and SSc.

Results

SSc ≥7 was significantly associated with the absence of echocardiographic response to CRT (OR: 0.327; 95% C.I. 0.155–0.689; p=0.003), while the presence of fQRS at baseline ECG was not (OR: 1.133; 95% C.I. 0.539–2.381; p=0.742). No correlation was found between SSc and overall mortality, cardiac death, ventricular arrhythmias, hospitalizations due to heart failure, or for MACE. Similar results were observed between fQRS and all secondary endpoints.

Conclusion

In HF patients with true-LBBB and LVEF ≤35% eligible for CRT, myocardial scar assessed by calculating the SSc on preimplant ECG is an independent predictor of nonresponse after multiple adjustments. Neither SSc nor fQRS is associated with overall and cardiac death, ventricular arrhythmias, or hospitalization for heart failure at a 24-month follow-up.

Localization of Left Ventricular Lead Electrodes in Relation to Myocardial Scar in Patients Undergoing Cardiac Resynchronization Therapy

Background

The efficacy of cardiac resynchronization therapy may be reduced in the event of pacing within myocardial fibrosis. We aimed to develop a method to determine the anatomical relationships between the left ventricular (LV) lead and myocardial fibrosis.

Methods and Results

In consecutive patients indicated for cardiac resynchronization therapy, cardiovascular magnetic resonance imaging with late gadolinium enhancement assessment was performed before implantation. After implantation, an injected computed tomography scanner (CT scan) was performed. The 2 imaging techniques were fused to assess the LV lead position relative to myocardial scar. A total of 68 patients were included. Myocardial scar was found in 29 (43%) and was localized in lateral segments in 14 (21%). Scar was significantly associated with male sex, ischemic cardiomyopathy, a Selvester score adapted to left bundle branch block (LBBB Selvester), and Selvester criteria for localizing lateral fibrosis (V2 S/S′ ratio). Image fusion was feasible in all patients. Position within myocardial scar was confirmed for 6 electrodes in 3 patients. Prolonged QRS duration during LV pacing ≥139% predicted electrode positioning within scar tissue (sensitivity, 83%; specificity, 91%; P=0.002).

Conclusions

In cardiac resynchronization therapy patients, fusion between preimplantation cardiovascular magnetic resonance and a postimplantation injected computed tomography scan is a feasible technique. Prolongation of the QRS duration during LV pacing predicts pacing within myocardial scar. Accurate location of LV lead pacing electrodes on the epicardial surface relative to myocardial scar, either by imaging or ECG analyses, may help improve cardiac resynchronization therapy response in selected patients.

Electrocardiography scar quantification correlates with scar size of hypertrophic cardiomyopathy seen by multidetector computed tomography

BACKGROUND

Hypertrophic cardiomyopathy (HCM), a genetically transmitted disease, is the most common genetic cardiovascular disease. Current strategies to stratify risk are expensive and concentrated in wealthy centers. Twelve-lead electrocardiography (ECG) is inexpensive, universally available, and can be readily used for Selvester QRS scoring, which estimates scar size. This study aimed to establish the relation between ECG scar quantification and myocardial fibrosis (extent of myocardial delayed enhancement) in multidetector computed tomography (MDCT).

HYPOTHESIS

There is a significant association between ECG scar quantification and the extent of myocardial delayed enhancement in MDCT.

METHODS

Seventy-five patients with HCM underwent a routine clinical evaluation and echocardiography, 12-lead ECG, and MDCT study. Patients with and without an implantable cardioverter-defibrillator were included.

RESULTS

The estimated Selvester QRS score of myocardial fibrosis was correlated significantly (R = 0.70; P < 0.01) with the quantified MDCT fibrosis. Compared with MDCT, the QRS score had 84.8% sensitivity and 88.8% specificity. Myocardial fibrosis was present in 88% of these patients with HCM (fibrotic mass, 9.87 ±10.8 g) comprising 5.66% ±6.16% of the total myocardial mass seen on the MDCT images. The Selvester QRS score reliably predicted the fibrotic mass in 76% of patients, which estimated 8.44% ±7.39% of the total myocardial mass.

CONCLUSIONS

The Selvester QRS score provides reliable quantification of myocardial fibrosis and was well correlated with MDCT in patients with HCM.

Semi-automated QRS score as a predictor of survival in CRT treated patients with strict left bundle branch block

BACKGROUND

Cardiac Resynchronization Therapy (CRT) is widely used for treating selected heart failure patients, but patients with myocardial scar respond worse to treatment. The Selvester QRS scoring system estimates myocardial scar burden using 12-lead ECG. This study's objective was to investigate the scores correlation to mortality in a CRT population.

METHODS AND RESULTS

Data on consecutive CRT patients was collected. 401 patients with LBBB and available ECG data were included in the study. QuAReSS software was used to perform Selvester scoring. Mean Selvester score was 6.4, corresponding to 19% scar burden. The endpoint was death or heart transplant; outcome was analyzed using Cox proportional hazards models. A Selvester score >8 was significantly associated with higher risk of the combined endpoint (HR 1.59, p=.014, CI 1.09-2.3).

CONCLUSION

Higher Selvester scores correlate to mortality in CRT patients with strict LBBB and might be of value in prognosticating survival.

Evaluation of the ECG based Selvester scoring method to estimate myocardial scar burden and predict clinical outcome in patients with left bundle branch block, with comparison to late gadolinium enhancement CMR imaging

BACKGROUND

Myocardial scar burden quantification is an emerging clinical parameter for risk stratification of sudden cardiac death and prediction of ventricular arrhythmias in patients with left ventricular dysfunction. We investigated the relationships among semiautomated Selvester score burden and late gadolinium enhancement-cardiovascular magnetic resonance (LGE-CMR) assessed scar burden and clinical outcome in patients with underlying heart failure, left bundle branch block (LBBB) and implantable cardioverter-defibrillator (ICD) treatment.

METHODS

Selvester QRS scoring was performed on all subjects with ischemic and nonischemic dilated cardiomyopathy at Skåne University Hospital Lund (2002-2013) who had undergone LGE-CMR and 12-lead ECG with strict LBBB pre-ICD implantation.

RESULTS

Sixty patients were included; 57% nonischemic dilated cardiomyopathy and 43% ischemic cardiomyopathy with mean left ventricular ejection fraction of 27.6% ± 11.7. All patients had scar by Selvester scoring. Sixty-two percent had scar by LGE-CMR (n = 37). The Spearman correlation coefficient for LGE-CMR and Selvester score derived scar was r = .35 (p = .007). In scar negative LGE-CMR, there was evidence of scar by Selvester scoring in all patients (range 3%-33%, median 15%). Fourteen patients (23%) had an event during the follow-up period; 11 (18%) deaths and six adequate therapies (10%). There was a moderate trend indicating that presence of scar increased the risk of clinical endpoints in the LGE-CMR analysis (p = .045).

CONCLUSION

There is a modest correlation between LGE-CMR and Selvester scoring verified myocardial scar. CMR based scar burden is correlated to clinical outcome, but Selvester scoring is not. The Selvester scoring algorithm needs to be further refined in order to be clinically relevant and reliable for detailed scar evaluation in patients with LBBB.