Abnormal P-wave terminal force in lead V1 is a marker for atrial electrical dysfunction but not structural remodelling

P-wave terminal force is related to left pulmonary vein reconnection in patients with atrial fibrillation recurrence after pulmonary vein isolation

In patients with atrial fibrillation (AF) recurrence after pulmonary vein (PV) isolation, noninvasive markers predicting PV reconnection or PV reconnection sites have not been fully elucidated. This study investigated the relationship between the P-wave terminal force in lead V1 (PTFV1) and the PV reconnection or reconnection site in patients with AF recurrence. We retrospectively studied consecutive patients who underwent second AF ablation between April 1, 2018, and June 1, 2023. PTFV1 was investigated before the first AF ablation (pre-ablation PTFV1) and before the second AF ablation (post-ablation PTFV1). In addition, we examined the ratio of the post-ablation to pre-ablation PTFV1 (PTFV1 ratio). These values were compared between patients with and without PV reconnection, with and without left PV (LPV) reconnection, and with and without right PV (RPV) reconnection. The analysis included 56 patients. PTFV1 was reduced because of the first AF ablation. In addition, the values were more decreased in patients without PV reconnection than with PV reconnection. The PTFV1 ratio was significantly smaller in the patients without LPV reconnection than with LPV reconnection; no significant difference was observed between the patients with and without RPV reconnection. Receiver operating characteristic curve analysis showed that a PTFV1 ratio > 0.69 predicted LPV reconnection with 70.0% sensitivity and 66.7% specificity. In conclusion, the PTFV1 ratio may be a noninvasive marker predicting LPV reconnection in patients with AF recurrence.

The Association of New Onset Postoperative Atrial Fibrillation and Abnormal P-Terminal Force in Lead V1 After On-Pump Cardiac Surgery

Introduction: Postoperative atrial fibrillation (POAF) after cardiac surgery is associated with higher morbidity and mortality. This paper presents several studies that conclude the presence of an aberrant p-terminal force vector in lead V1 (PTFV1) has been identified as a significant predictor of atrial fibrillation in the non-surgical population. It is uncertain whether or not there is an association of PTFV1 and new-onset POAF in patients after cardiac surgery. Methods: In this secondary analysis, adult patients undergoing on-pump cardiac surgery for aortocoronary bypasses, valve surgery, combined bypass, and valve surgery were analyzed from 12/2018 to 08/2020. Patients who had a previous occurrence of atrial fibrillation or atrial flutter, patients with pacemakers and/or Implantable Cardioverter-Defibrillators (ICDs), and those who did not have an electrocardiogram (ECG) performed within the 3 months before surgery were excluded. In addition, ECGs that were considered to be of low quality were also removed. Preoperative 12-lead ECGs were examined and the PTFV1 was measured. Secondarily, we examined the P-wave length in lead II, the area under the P-wave in lead II, PR interval, and QRS duration in lead V1 and II. The occurrence of POAF was extracted from the hospital record. Results: Out of a total of 252 patients, 62 patients (24.6%) developed new onset POAF during their hospital stay. POAF occurred primarily in older patients, with poor renal function, and exhibited larger left atria. Analysis of ORs (odds ratios) revealed that age, creatinine clearance, valve surgery, and left atrial volume index (LAVI) were associated with POAF. In the context of the multivariable analysis, it was demonstrated that only age presented a significant correlation with postoperative atrial fibrillation (POAF). There was no observed relationship between any of the parameters based on ECG and the occurrence of POAF. Conclusion: No association was found between PTFV1 or other ECG-based measurements and new onset POAF in cardiac surgery patients. Age was the only independent predictor of POAF.

High prevalence of atrial conduction abnormalities in Lewy body disease - a marker of cardiac complications?

Increasing evidence suggests that Lewy body disease (LBD) is associated with clinically important cardiac complications, including sick sinus syndrome, atrial fibrillation and sudden cardiac death. The high prevalence of sick sinus syndrome and atrial fibrillation in LBD suggests the presence of disease-related atrial conduction disorders. To explore whether LBD is associated with atrial conduction disorders, electrocardiographic (ECG) P wave parameters were analyzed in a cohort of LBD patients (n = 74), using age-matched Alzheimer's disease (AD) patients (n = 25) as controls. P wave terminal force in V1 and P wave duration were found to be significantly greater in the LBD group than in the AD group. In addition, 43 (58%) individuals in the LBD exhibited pathological P wave terminal force (> 4000 µV*ms) vs 3 (12%) in the AD group, and 60 (81%) in the LBD group exhibited pathological P wave duration (≥ 120 ms), vs 13 (52%) in the AD group. The difference could not be explained by atrial fibrillation or atrial enlargement on echocardiogram. The clinical significance of pathological P wave parameters in LBD is unknown, but their presence suggests an atrial cardiomyopathy that could be due to cardiac alpha-synuclein deposition, autonomic dysfunction, or a combination thereof. Future research is warranted to elucidate whether this proposed disease-related atrial cardiomyopathy is related to cardiac alpha-synuclein deposition, whether it is causally related to cardiac complications in LBD, and whether pathological P wave parameters hold potential as a screening tool for cardiac complications in LBD.

Gene editing in common cardiovascular diseases

Cardiovascular diseases are the leading cause of morbidity and mortality worldwide, highlighting the high socioeconomic impact. Current treatment strategies like compound-based drugs or surgeries are often limited. On the one hand, systemic administration of substances is frequently associated with adverse side effects; on the other hand, they typically provide only short-time effects requiring daily intake. Thus, new therapeutic approaches and concepts are urgently needed. The advent of CRISPR-Cas9 genome editing offers great promise for the correction of disease-causing hereditary mutations. As such mutations are often very rare, gene editing strategies to correct them are not broadly applicable to many patients. Notably, there is recent evidence that gene editing technology can also be deployed to disrupt common pathogenic signaling cascades in a targeted, specific, and efficient manner, which offers a more generalizable approach. However, several challenges remain to be addressed ranging from the optimization of the editing strategy itself to a suitable delivery strategy up to potential immune responses to the editing components. This review article discusses important CRISPR-Cas9-based gene editing approaches with their advantages and drawbacks and outlines opportunities in their application for treatment of cardiovascular diseases.

P-wave terminal force in lead V1 is associated with recurrence after catheter ablation in patients with paroxysmal atrial fibrillation and normal left atrial size

Background

A previous investigation reported that an abnormal P-wave terminal force in lead V1 (PTFV1) is a marker for electrical remodeling of the left atrium (LA). We aimed to assess the relationship of PTFV1 with LA tachyarrhythmia (LATA) recurrence after radiofrequency catheter ablation (RFCA) in patients with paroxysmal atrial fibrillation (PAF) and normal LA size.

Methods

Patients with PAF and normal LA size (LA volume index < 34 ml/m2) who underwent RFCA were consecutively included between January 2018 and December 2020 and divided into two groups based on the presence (recurrence group) or absence (nonrecurrence group) of LATA recurrence. PTFV1 was measured according to preprocedural electrocardiography. The association between PTFV1 and the recurrence of LATA was investigated.

Results

A total of 385 patients were included. After a median follow-up period of 745 (467, 977) days, 109 (28.3%) patients experienced LATA recurrence. PTFV1 was greater in the recurrence group. Multivariate Cox regression analysis demonstrated that the hazard ratio and 95% confidence interval for PTFV1 per 1,000 μV*ms increase and PTFV1 > 4,000 μV*ms were 1.22 (1.13-1.32, p < 0.001) and 2.32 (1.54-3.48, p < 0.001), respectively.

Conclusion

PTFV1 is an independent predictor for LATA recurrence after RFCA in patients with PAF and normal LA size.

The effect of fixed and functional remodelling on conduction velocity, wavefront propagation, and rotational activity formation in atrial fibrillation

AIMS

Pathophysiology of atrial fibrillation (AF) remains unclear. Interactions between scar and conduction velocity (CV) and their impact on wavefront propagation in sinus rhythm (SR) and rotational activity burden in AF were evaluated.

METHODS AND RESULTS

Local activation times (LATs) and voltage data were obtained from patients undergoing ablation for persistent AF. Omnipolar voltage (OV) and bipolar voltage (BV) data were obtained during AF and SR at pacing intervals of 600 and 250 ms. Local activation times were used to determine CV dynamics and their relationship to the underlying voltage and pivot points in SR. Computational modelling studies were performed to evaluate the impact of CVs and fibrosis on rotational activity burden in AF. Data from 60 patients with a total of 2 768 400 LAT and voltage points were analysed (46 140 ± 5689 points/patient). Voltage determined CV dynamics. Enhanced CV heterogeneity sites were predominantly mapped to low-voltage zones (LVZs) (0.2-0.49 mV) (128/168, 76.2%) rather than LVZs (<0.2 mV) and frequently co-located to pivot points (151/168, 89.9%). Atrial fibrillation OV maps correlated better with SR BV 250 ms than 600 ms maps, thereby representing fixed and functional remodelling. Sinus rhythm maps at 250 ms compared with 600 ms harboured a greater number of pivot points. Increased CV slowing and functional remodelling on computational models resulted in a greater rotational activity burden.

CONCLUSION

Conduction velocity dynamics are impacted by the degree of scar. Conduction velocity heterogeneity and functional remodelling impacts wavefront propagation in SR and rotational activity burden in AF. This study provides insight into the pathophysiology of AF and identifies potential novel ablation targets.

Atrial cardiomyopathy revisited-evolution of a concept: a clinical consensus statement of the European Heart Rhythm Association (EHRA) of the ESC, the Heart Rhythm Society (HRS), the Asian Pacific Heart Rhythm Society (APHRS), and the Latin American Heart Rhythm Society (LAHRS)

AIMS

The concept of "atrial cardiomyopathy" (AtCM) had been percolating through the literature since its first mention in 1972. Since then, publications using the term were sporadic until the decision was made to convene an expert working group with representation from four multinational arrhythmia organizations to prepare a consensus document on atrial cardiomyopathy in 2016 (EHRA/HRS/APHRS/SOLAECE expert consensus on atrial cardiomyopathies: definition, characterization, and clinical implication). Subsequently, publications on AtCM have increased progressively.

METHODS AND RESULTS

The present consensus document elaborates the 2016 AtCM document further to implement a simple AtCM staging system (AtCM stages 1-3) by integrating biomarkers, atrial geometry, and electrophysiological changes. However, the proposed AtCM staging needs clinical validation. Importantly, it is clearly stated that the presence of AtCM might serve as a substrate for the development of atrial fibrillation (AF) and AF may accelerates AtCM substantially, but AtCM per se needs to be viewed as a separate entity.

CONCLUSION

Thus, the present document serves as a clinical consensus statement of the European Heart Rhythm Association (EHRA) of the ESC, the Heart Rhythm Society (HRS), the Asian Pacific Heart Rhythm Society (APHRS), and the Latin American Heart Rhythm Society (LAHRS) to contribute to the evolution of the AtCM concept.

Association between P-wave terminal force in lead V1 and extent of left atrial low-voltage substrate in older patients with paroxysmal atrial fibrillation

BACKGROUND

The P-wave terminal force in lead V1 (PTFV1) is a marker of cardiomyopathy and risk of atrial fibrillation (AF). Low-voltage area (LVA) in the left atrium (LA), which indicates underlying atrial fibrosis, could predict AF recurrence. This study aimed to investigate the correlation between PTFV1 and LVA in older patients with paroxysmal AF.

METHODS

From May 1, 2020, to October 31, 2021, a total of 162 patients aged 65-80 years with paroxysmal AF who underwent index ablation procedures were enrolled. PTFV1 was measured in sinus rhythm (SR) using 12-lead electrocardiograms prior to the ablation. Abnormal PTFV1 was defined as a ≥ 4 mVms depression. Additional LVA ablation beyond circumferential pulmonary vein isolation (CPVI) was performed if LVAs were found.

RESULTS

Among the 162 patients, 88 had a normal PTFV1 and 74 had an abnormal PTFV1 prior to ablation. There was a significant difference in LVA in patients with and without an abnormal PTFV1 (LVA, 11.0 vs. 5.1 cm2, P < 0.001; LVA burden, 8.9% vs. 4.5%, P < 0.001). PTFV1 and PTAV1 were highest in the upper tertile with extensive LVAs (P < 0.001). Multivariate analysis revealed that abnormal PTFV1 was an independent predictor of LVAs (β = 4.961; 95% CI, 2.135-7.788; P < 0.001). After a median follow-up of 23 months, the AF-free survival rate was similar between the normal PTFV1 group and the abnormal PTFV1 group (13/88 vs. 12/74, hazard ratio [HR], 0.933 [95% CI, 0.425-2.047]; P = 0.861).

CONCLUSIONS

Abnormal PTFV1 at baseline was independently associated with the extent of LVA in older patients with paroxysmal AF.

Association of the interatrial block and left atrial fibrosis in the patients without history of atrial fibrillation

Presence of left atrial (LA) fibrosis reflects underlying atrial cardiomyopathy. Interatrial block (IAB) is associated with LA fibrosis in patients with atrial fibrillation (AF). The association of IAB and LA fibrosis in the patients without history of AF is unknown. We examined association of IAB and LA fibrosis in the patients without AF history. This is a retrospective analysis of 229 patients undergoing cardiac magnetic resonance imaging (CMR). LA fibrosis was reported from spatial extent of late gadolinium enhancement of CMR. IAB was measured from 12-lead electrocardiography using digital caliper. Of 229 patients undergoing CMR, prevalence of IAB was 50.2%. Patients with IAB were older (56.9±13.9 years vs. 45.9±19.2 years, p<0.001) and had higher prevalence of co-morbidities. Left ventricular ejection fraction was lower in IAB group. LA volume index (LAVI) was greater in IAB group (54.6±24.9 ml/m2 vs. 43.0±21.1 ml/m2, p<0.001). Patients with IAB had higher prevalence of LA fibrosis than those without IAB (70.4% vs. 21.2%; p<0.001). After multivariable analysis, only IAB and LAVI were independent factors that predict LA fibrosis. Prevalence of IAB in patients undergoing CMR was high. IAB was highly associated with LA fibrosis and larger LA size in patients without AF history.

CRISPR-Cas9 base editing of pathogenic CaMKIIδ improves cardiac function in a humanized mouse model

Cardiovascular diseases are the most common cause of worldwide morbidity and mortality, highlighting the necessity for advanced therapeutic strategies. Ca2+/calmodulin-dependent protein kinase IIδ (CaMKIIδ) is a prominent inducer of various cardiac disorders, which is mediated by 2 oxidation-sensitive methionine residues within the regulatory domain. We have previously shown that ablation of CaMKIIδ oxidation by CRISPR-Cas9 base editing enables the heart to recover function from otherwise severe damage following ischemia/reperfusion (IR) injury. Here, we extended this therapeutic concept toward potential clinical translation. We generated a humanized CAMK2D knockin mouse model in which the genomic sequence encoding the entire regulatory domain was replaced with the human sequence. This enabled comparison and optimization of two different editing strategies for the human genome in mice. To edit CAMK2D in vivo, we packaged the optimized editing components into an engineered myotropic adeno-associated virus (MyoAAV 2A), which enabled efficient delivery at a very low AAV dose into the humanized mice at the time of IR injury. CAMK2D-edited mice recovered cardiac function, showed improved exercise performance, and were protected from myocardial fibrosis, which was otherwise observed in injured control mice after IR. Our findings identify a potentially effective strategy for cardioprotection in response to oxidative damage.

Prognostic Value of PtfV1 in Long-Term Outcomes of Patients with Unstable Angina

Background

P-wave terminal force in lead V1 (PtfV1) irregularity has been associated with various cardiovascular conditions, including atrial fibrillation, left ventricular diastolic dysfunction, valvular heart disease, congestive heart failure, stroke, and mortality. However, its prognostic value for unstable angina (UA) has not been extensively studied. To address this knowledge gap, this study aimed to evaluate the long-term predictive significance of PtfV1 at discharge for UA patients.

Methods

A total of 707 patients with newly diagnosed UA were included in this study. PtfV1 measurements were recorded at admission and discharge. PtfV1(+) was defined as an absolute value above 0.04mm·s, while PtfV1(-) was defined as an absolute value below 0.04mm·s. Based on their PtfV1 values at discharge, patients were categorized into two groups: PtfV1(-) and PtfV1(+). Univariate and multivariate regression analyses were conducted to identify variables that could potentially contribute to the risk of UA.

Results

Univariate analysis revealed a higher incidence of total adverse outcomes and major adverse cardiovascular events (MACE) in the PtfV1(+) group compared to the PtfV1(-) group, with a risk ratio (RR) of 2.006 [95% confidence interval (95% CI): 1.389-2.896] for total outcomes and an RR of 2.759 (95% CI: 1.870-4.070) for MACE. After adjusting for confounding factors through multivariate analysis, participants with PtfV1(+) had a 46% increased risk [adjusted hazard ratio (HR): 1.458; 95% CI: 1.010-2.104]for total adverse outcomes and an 86% increased risk (adjusted HR: 1.863; 95% CI: 1.246-2.786) for MACE compared to those with PtfV1(-).

Conclusion

The presence of PtfV1(+) at discharge is an independent predictor of poor outcomes and provides extended prognostic information for UA patients.

Elimination of CaMKIIδ Autophosphorylation by CRISPR-Cas9 Base Editing Improves Survival and Cardiac Function in Heart Failure in Mice

BACKGROUND

Cardiovascular diseases are the main cause of worldwide morbidity and mortality, highlighting the need for new therapeutic strategies. Autophosphorylation and subsequent overactivation of the cardiac stress-responsive enzyme CaMKIIδ (Ca2+/calmodulin-dependent protein kinase IIδ) serves as a central driver of multiple cardiac disorders.

METHODS

To develop a comprehensive therapy for heart failure, we used CRISPR-Cas9 adenine base editing to ablate the autophosphorylation site of CaMKIIδ. We generated mice harboring a phospho-resistant CaMKIIδ mutation in the germline and subjected these mice to severe transverse aortic constriction, a model for heart failure. Cardiac function, transcriptional changes, apoptosis, and fibrosis were assessed by echocardiography, RNA sequencing, terminal deoxynucleotidyl transferase dUTP nick end labeling staining, and standard histology, respectively. Specificity toward CaMKIIδ gene editing was assessed using deep amplicon sequencing. Cellular Ca2+ homeostasis was analyzed using epifluorescence microscopy in Fura-2-loaded cardiomyocytes.

RESULTS

Within 2 weeks after severe transverse aortic constriction surgery, 65% of all wild-type mice died, and the surviving mice showed dramatically impaired cardiac function. In contrast to wild-type mice, CaMKIIδ phospho-resistant gene-edited mice showed a mortality rate of only 11% and exhibited substantially improved cardiac function after severe transverse aortic constriction. Moreover, CaMKIIδ phospho-resistant mice were protected from heart failure-related aberrant changes in cardiac gene expression, myocardial apoptosis, and subsequent fibrosis, which were observed in wild-type mice after severe transverse aortic constriction. On the basis of identical mouse and human genome sequences encoding the autophosphorylation site of CaMKIIδ, we deployed the same editing strategy to modify this pathogenic site in human induced pluripotent stem cells. It is notable that we detected a >2000-fold increased specificity for editing of CaMKIIδ compared with other CaMKII isoforms, which is an important safety feature. While wild-type cardiomyocytes showed impaired Ca2+ transients and an increased frequency of arrhythmias after chronic β-adrenergic stress, CaMKIIδ-edited cardiomyocytes were protected from these adverse responses.

CONCLUSIONS

Ablation of CaMKIIδ autophosphorylation by adenine base editing may offer a potential broad-based therapeutic concept for human cardiac disease.

The Role of Electrocardiographic Markers for Predicting Atrial Fibrillation in Patients with Acute Ischemic Stroke: Data from the BIOSIGNAL Cohort Study

BACKGROUND AND AIMS

P-wave abnormalities in the 12-lead electrocardiogram (ECG) have been associated with a higher risk of acute ischemic stroke (AIS) as well as atrial fibrillation (AF). This study aimed to assess pre-determined ECG criteria during sinus rhythm in unselected AIS patients and their value for predicting newly diagnosed atrial fibrillation (NDAF) after hospital admission.

METHODS

P-wave alterations were measured on 12-lead ECG on admission in all consecutively enrolled patients without known AF between October 2014 and 2017. The outcome of interest was NDAF, identified by prolonged electrocardiographic monitoring within one year after the index AIS. Univariable and multivariable logistic regression was applied to assess the magnitude and independence of the association between pre-selected ECG markers and NDAF. The discriminatory accuracy was evaluated with the area under the receiver operating characteristic curve (AUC), and the incremental prognostic value was estimated with the net reclassification index.

RESULTS

NDAF was detected in 87 (10%) of 856 patients during a follow-up of 365 days. Out of the pre-selected ECG parameters, advanced interatrial block (aIAB) and PR interval in lead II were independently associated with NDAF in univariable regression analysis. Only aIAB remained a significant predictor in multivariable analysis. Adding aIAB to the best-performing multivariable regression model improved the discriminatory accuracy to predict NDAF from an AUC of 0.78 (95%-CI 0.77-0.80) to 0.81 (95%-CI 0.80-0.83, p < 0.001).

CONCLUSION

aIAB is independently and highly associated with NDAF in patients with AIS, has high inter-rater reliability, and therefore may be helpful to refine diagnostic work-up to search for AF in AIS.

Predicting stroke and mortality in mitral stenosis with atrial flutter: A machine learning approach

BACKGROUND

Our study hypothesized that an intelligent gradient boosting machine (GBM) model can predict cerebrovascular events and all-cause mortality in mitral stenosis (MS) with atrial flutter (AFL) by recognizing comorbidities, electrocardiographic and echocardiographic parameters.

METHODS

The machine learning model was used as a statistical analyzer in recognizing the key risk factors and high-risk features with either outcome of cerebrovascular events or mortality.

RESULTS

A total of 2184 patients with their chart data and imaging studies were included and the GBM analysis demonstrated mitral valve area (MVA), right ventricular systolic pressure, pulmonary artery pressure (PAP), left ventricular ejection fraction (LVEF), New York Heart Association (NYHA) class, and surgery as the most significant predictors of transient ischemic attack (TIA/stroke). MVA, PAP, LVEF, creatinine, hemoglobin, and diastolic blood pressure were predictors for all-cause mortality.

CONCLUSION

The GBM model assimilates clinical data from all diagnostic modalities and significantly improves risk prediction performance and identification of key variables for the outcome of MS with AFL.

P-wave terminal force in lead V1 and outcomes in patients with persistent atrial fibrillation undergoing catheter ablation

AIMS

The P-wave terminal force in electrocardiogram lead V1 (PTFV1) correlates with outcomes in patients with paroxysmal atrial fibrillation (AF). Nevertheless, the correlation between the PTFV1 and outcomes after AF ablation in patients with persistent AF remains unclear. This study aimed to determine whether the PTFV1 at 3 months after AF ablation could predict AF recurrence and cardiovascular events in patients with persistent AF.

METHODS

This historical cohort study examined 453 consecutive patients with persistent AF who underwent a first-time AF ablation. We measured the PTFV1 at 3 months after the ablation. An abnormal PTF was defined as a ≥4 mVms depression. The 3-year incidence of AF recurrence and composite cardiovascular events, including strokes, heart failure hospitalizations, and cardiovascular death, were compared between the abnormal and normal PTF groups.

RESULTS

Among 434 enrolled patients, 101 had an abnormal, and 333 normal PTF at 3 months after AF ablation. Compared with the normal PTF group, the abnormal PTF group had a significantly higher incidence of AF recurrence (52.6% vs 28.1%, log-rank P < .001) and cardiovascular events (13.7% vs 2.6%, log-rank P = .005). After adjusting for the risk factors, an abnormal PTF was established as an independent predictor of AF recurrence (hazard ratio [HR] 2.12, 95% confidence interval [CI]: 1.44-3.13, P < .001) and cardiovascular events (HR 3.26, 95% CI: 1.19-8.97, P = .022).

CONCLUSIONS

The PTFV1 at 3 months after AF ablation could be a valuable noninvasive predictor of both AF recurrence and cardiovascular events in patients with persistent AF.

P-wave terminal force in lead V1 and atrial fibrillation burden in cryptogenic stroke with implantable loop recorders

Implantable loop recorders (ILRs) are useful for the detection of atrial fibrillation (AF) in patients with cryptogenic stroke (CS). P-wave terminal force in lead V₁ (PTFV₁) is associated with AF detection; however, data on the association between PTFV₁ and AF detection using ILRs in patients with CS are limited. Consecutive patients with CS with implanted ILRs from September 2016 to September 2020 at eight hospitals in Japan were studied. PTFV₁ was calculated by 12-lead ECG before ILRs implantation. An abnormal PTFV₁ was defined as ≥ 4.0 mV × ms. The AF burden was calculated as a proportion based on the duration of AF to the total monitoring period. The outcomes included AF detection and large AF burden, which was defined as ≥ 0.5% of the overall AF burden. Of 321 patients (median age, 71 years; male, 62%), AF was detected in 106 patients (33%) during the median follow-up period of 636 days (interquartile range [IQR], 436-860 days). The median time from ILRs implantation to AF detection was 73 days (IQR, 14-299 days). An abnormal PTFV₁ was independently associated with AF detection (adjusted hazard ratio, 1.71; 95% confidence interval [CI], 1.00-2.90). An abnormal PTFV₁ was also independently associated with a large AF burden (adjusted odds ratio, 4.70; 95% CI, 2.50-8.80). In patients with CS with implanted ILRs, an abnormal PTFV₁ is associated with both AF detection and a large AF burden.Clinical Trial Registration Information: UMIN Clinical Trials Registry 000044366.

Electrocardiographic markers of atrial cardiomyopathy and risk of heart failure in the multi-ethnic study of atherosclerosis (MESA) cohort

Background

The association of electrocardiographic (ECG) markers of atrial cardiomyopathy with heart failure (HF) and its subtypes is unclear.

Methods

This analysis included 6,754 participants free of clinical cardiovascular disease (CVD), including atrial fibrillation (AF), from the Multi-Ethnic Study of Atherosclerosis. Five ECG markers of atrial cardiomyopathy (P-wave terminal force in V1 [PTFV1], deep-terminal negativity in V1 [DTNV1], P-wave duration [PWD], P-wave axis [PWA], advanced intra-atrial block [aIAB]) were derived from digitally recorded electrocardiograms. Incident HF events through 2018 were centrally adjudicated. An ejection fraction (EF) of 50% at the time of HF was used to classify HF as HF with reduced EF (HFrEF), HF with preserved EF (HFpEF), or unclassified HF. Cox proportional hazard models were used to examine the associations of markers of atrial cardiomyopathy with HF. The Lunn-McNeil method was used to compare the associations in HFrEF vs. HFpEF.

Results

413 HF events occurred over a median follow-up of 16 years. In adjusted models, abnormal PTFV1 (HR (95%CI): 1.56(1.15-2.13), abnormal PWA (HR (95%CI):1.60(1.16-2.22), aIAB (HR (95%CI):2.62(1.47-4.69), DTNPV1 (HR (95%CI): 2.99(1.63-7.33), and abnormal PWD (HR (95%CI): 1.33(1.02-1.73), were associated with increased HF risk. These associations persisted after further adjustments for intercurrent AF events. No significant differences in the strength of association of each ECG predictor with HFrEF and HFpEF were noted.

Conclusions

Atrial cardiomyopathy defined by ECG markers is associated with HF, with no differences in the strength of association between HFrEF and HFpEF. Markers of atrial Cardiomyopathy may help identify individuals at risk of developing HF.

High-Sensitivity C-Reactive Protein Modifies P-Wave Terminal Force in Lead V1-Associated Prognosis in Acute Ischemic Stroke or TIA Patients

Little is known about the role of high-sensitivity C-reactive protein (hsCRP) in the relationship between P-wave terminal force in lead V1 (PTFV1) and stroke prognosis. We aimed to investigate how hsCRP influences the effect of PTFV1 on ischemic stroke recurrence and mortality. In this study, patients enrolled in the Third China National Stroke Registry, which enrolled consecutive patients who had suffered an ischemic stroke or transient ischemic attack in China, were analyzed. After excluding patients with atrial fibrillation, 8271 patients with PTFV1 and hsCRP measurements were included in this analysis. Cox regression analyses were used to assess the association between PTFV1 and stroke prognosis according to different inflammation statuses stratified by an hsCRP level of 3 mg/L. A total of 216 (2.6%) patients died, and 715 (8.6%) patients experienced ischemic stroke recurrence within 1 year. In patients with hsCRP levels ≥ 3 mg/L, elevated PTFV1 was significantly associated with mortality (HR, 1.75; 95% CI, 1.05-2.92; p = 0.03), while in those with hsCRP levels < 3 mg/L, such an association did not exist. In contrast, in patients with hsCRP levels < 3 mg/L and those with hsCRP levels ≥ 3 mg/L, elevated PTFV1 remained significantly associated with ischemic stroke recurrence. The predictive role of PTFV1 towards mortality but not ischemic stroke recurrence differed in terms of hsCRP levels.

Atrial cardiomyopathy markers predict ischemic cerebrovascular events independent of atrial fibrillation in patients with acute myocardial infarction

Background

Contemporary data on atrial cardiomyopathy (ACM) markers and ischemic cerebrovascular events (ICVE) in patients with acute myocardial infarction (AMI) is lacking. We aimed to examine whether ACM markers predict ICVE among AMI patients.

Materials and methods

A total of 4,206 AMI cases diagnosed in clinical examinations between January 2016 and June 2021 were assessed for markers of ACM including B-type natriuretic peptide (BNP), P-wave terminal force in ECG lead V1 (PTFV1), and left atrium diameter (LAD). Left atrial enlargement (LAE) and abnormal PTFV1 were defined by previously published cut-off points. The primary outcome was incident ICVE composed of ischemic stroke (IS) and transient ischemic attack (TIA). Receiver operating curve analyses were used to compare the predictive performance of the CHA2DS2-VASc score combined with ACM markers to the CHA2DS2-VASc score alone.

Results

During a median follow-up of 44.0 months, 229 (5.44%) ICVE occurred. Of these, 156 individuals developed IS and the remaining 73 cases were diagnosed with TIAs. The ICVE group showed larger PTFV1 and increased LAD as well as elevated BNP levels at baseline. In the multivariate analysis, we found significant associations with ICVE for PTFV1 (HR per 1,000 μV*ms, 1.143; 95% CI, 1.093–1.196), LAD (HR per millimeter, 1.148; 95% CI, 1.107–1.190), but not BNP after adjusting for known ICVE risk factors and interim atrial fibrillation (AF). The addition of abnormal PTFV1 and LAE improved the predictive accuracy of the CHA2DS2-VASc score with C-statistic increasing from 0.708 to 0.761 (p &lt; 0.001).

Conclusion

Atrial cardiomyopathy markers including PTFV1 and LAD were associated with incident ICVE independent of well-established risk factors and AF occurrence. The addition of ACM markers with CHA2DS2-VASc score may well discriminate individuals at high risk of ICVE in AMI patients.

Prognostic significance of atrial cardiopathy in patients with acute ischemic stroke

Introduction:

Whether atrial cardiopathy is associated with stroke prognosis remains unclear. We evaluated the association between atrial cardiopathy markers and outcomes in patients with ischemic stroke using a nationwide prospective registry.

Patients and methods:

Based on the Third China National Stroke Registry, we evaluated different atrial cardiopathy markers including increased P-wave terminal force in V1 (PTFV1), advanced interatrial block (aIAB), prolonged P-wave duration, prolonged P-wave dispersion, paroxysmal supraventricular tachycardia, premature atrial contractions, prolonged PR interval, and severe left atrial enlargement in ischemic stroke patients. The outcomes were death and ischemic stroke recurrence at 1 year. The association between atrial cardiopathy markers and outcomes was analyzed using Cox regression models.

Results:

At 1-year follow-up, 486 (3.4%) patients had died and 1317 (9.3%) patients had experienced ischemic stroke recurrence. After adjustment for clinical risk factors including atrial fibrillation, PTFV1 > 5000 μV·ms (adjusted hazard ratio [HR] 1.70, 95% confidence interval [CI]: 1.18–2.45, p = 0.004) and aIAB (adjusted HR 1.47, 95% CI: 1.14–1.91, p = 0.003) were significantly associated with mortality. PTFV1 > 5000 μV·ms was significantly associated with ischemic stroke recurrence (adjusted HR 1.54, 95% CI: 1.22–1.96, p = 0.0004). This association was observed although we excluded patients diagnosed with atrial fibrillation.

Discussion and Conclusion:

Atrial cardiopathy markers, especially PTFV1 and aIAB, are significantly associated with a higher risk of poor prognosis in patients with ischemic stroke.

Atrial cardiomyopathy: from cell to bedside

Atrial cardiomyopathy refers to structural and electrical remodelling of the atria, which can lead to impaired mechanical function. While historical studies have implicated atrial fibrillation as the leading cause of cardioembolic stroke, atrial cardiomyopathy may be an important, underestimated contributor. To date, the relationship between atrial cardiomyopathy, atrial fibrillation, and cardioembolic stroke remains obscure. This review summarizes the pathogenesis of atrial cardiomyopathy, with a special focus on neurohormonal and inflammatory mechanisms, as well as the role of adipose tissue, especially epicardial fat in atrial remodelling. It reviews the current evidence implicating atrial cardiomyopathy as a cause of embolic stroke, with atrial fibrillation as a lagging marker of an increased thrombogenic atrial substrate. Finally, it discusses the potential of antithrombotic therapy in embolic stroke with undetermined source and appraises the available diagnostic techniques for atrial cardiomyopathy, including imaging techniques such as echocardiography, computed tomography, and magnetic resonance imaging as well as electroanatomic mapping, electrocardiogram, biomarkers, and genetic testing. More prospective studies are needed to define the relationship between atrial cardiomyopathy, atrial fibrillation, and embolic stroke and to establish a prompt diagnosis and specific treatment strategies in these patients with atrial cardiomyopathy for the secondary and even primary prevention of embolic stroke.

Atrial cardiomyopathy markers and new-onset atrial fibrillation risk in patients with acute myocardial infarction

BACKGROUND

New-onset atrial fibrillation (NOAF) after acute myocardial infarction (AMI) is common and independently correlated with poor prognosis. The purpose of this study is to explore whether atrial cardiomyopathy (ACM) markers improve NOAF risk assessment and contribute to therapy decision-making to improve prognosis.

METHODS

We retrospectively analyzed 4713 patients with AMI without a documented history of atrial fibrillation (AF). We measured markers of ACM including P-wave terminal force in ECG lead V1 (PTFV1), Left atrial dimension (LAD), and B-type natriuretic peptide (BNP). Patients were stratified into tertiles of PTFV1, LAD, and BNP levels. Associations between markers and NOAF were evaluated using logistic regression analysis.

RESULTS

Overall, 222 (4.71%) patients had NOAF out of 4713 patients. The prevalence of NOAF increased gradually with PTFV1, LAD, and BNP tertiles. On multivariable regression analysis with potential confounders, elevated PTFV1, LAD, and BNP markers were significantly associated with an increased risk of NOAF. The addition of PTFV1, LAD, and BNP to the AF risk factors recommended by the 2020 ESC Guidelines significantly improved risk discrimination for NOAF.

CONCLUSION

Atrial cardiomyopathy markers including PTFV1, LAD, and BNP were strongly associated with NOAF after AMI. The prediction performance of the clinical model for NOAF was increased by the addition of these markers.

Left Atrial Cardiomyopathy - A Challenging Diagnosis

Left atrial cardiomyopathy (LACM) has been an ongoing focus of research for several years. There is evidence that LACM is responsible for atrial fibrillation and embolic strokes of undetermined sources. Therefore, the correct diagnosis of LACM is of clinical importance. Various techniques, including electrocardiography, echocardiography, cardiac magnetic resonance imaging, computed tomography, electroanatomic mapping, genetic testing, and biomarkers, can both identify and quantify structural, mechanical as well as electrical dysfunction in the atria. However, the question arises whether these techniques can reliably diagnose LACM. Because of its heterogeneity, clinical diagnosis is challenging. To date, there are no recommendations for standardized diagnosis of suspected LACM. However, standardization could help to classify LACM more precisely and derive therapeutic directions to improve individual patient management. In addition, uniform diagnostic criteria for LACM could be important for future studies. Combining several parameters and relating them seems beneficial to approach the diagnosis of LACM. This review provides an overview of the current evidence regarding the diagnosis of LACM, in which several potential parameters are discussed and, consequently, a proposal for a diagnostic algorithm is presented.

Central Sleep Apnea Is Associated with an Abnormal P-Wave Terminal Force in Lead V1 in Patients with Acute Myocardial Infarction Independent from Ventricular Function

Sleep-disordered breathing (SDB) is highly prevalent in patients with cardiovascular disease. We have recently shown that an elevation of the electrocardiographic (ECG) parameter P wave terminal force in lead V₁ (PTFV₁) is linked to atrial proarrhythmic activity by stimulation of reactive oxygen species (ROS)-dependent pathways. Since SDB leads to increased ROS generation, we aimed to investigate the relationship between SDB-related hypoxia and PTFV₁ in patients with first-time acute myocardial infarction (AMI). We examined 56 patients with first-time AMI. PTFV₁ was analyzed in 12-lead ECGs and defined as abnormal when ≥4000 µV*ms. Polysomnography (PSG) to assess SDB was performed within 3–5 days after AMI. SDB was defined by an apnea-hypopnea-index (AHI) >15/h. The multivariable regression analysis showed a significant association between SDB-related hypoxia and the magnitude of PTFV₁ independent from other relevant clinical co-factors. Interestingly, this association was mainly driven by central but not obstructive apnea events. Additionally, abnormal PTFV₁ was associated with SDB severity (as measured by AHI, B 21.495; CI [10.872 to 32.118]; p < 0.001), suggesting that ECG may help identify patients suitable for SDB screening. Hypoxia as a consequence of central sleep apnea may result in atrial electrical remodeling measured by abnormal PTFV₁ in patients with first-time AMI independent of ventricular function. The PTFV₁ may be used as a clinical marker for increased SDB risk in cardiovascular patients.