Impaired left atrial strain in the presence of interatrial block in patients with type 2 diabetes mellitus

Left atrial strain associated with interatrial block in patients with ST-segment elevation myocardial infarction

Both interatrial block (IAB) and left atrium (LA) strain are associated with atrial arrhythmias in ST-segment elevation myocardial infarction (STEMI) patients, but the relationship between IAB and LA strain has not yet been reported. This study was to investigate the correlation between LA strain and IAB in STEMI patients. This is a single-center retrospective clinical observational study. The STEMI patients with primary percutaneous coronary intervention (pPCI) were enrolled, and all patients completed cardiac magnetic resonance (CMR). A standard 12-lead electrocardiogram (ECG) was recorded on the same day as CMR. IAB was measured by p duration on ECG at follow-up. 302 patients were enrolled, including 91 (30.1%) with IAB. The reservoir strain, conduit strain and booster strain were included in model 1, model 2 and model 3, respectively. In model 1, age (OR 1.025; 95%CI 1.003-1.047; p = 0.026), hypertension (OR 2.188; 95%CI 1.288-3.719; p = 0.004), and reservoir strain (OR 0.947; 95%CI 0.920-0.974; p < 0.001) were independent factors for IAB. In model 2, age (OR 1.031; 95%CI 1.009-1.053; p = 0.006), hypertension (OR 2.058; 95%CI 1.202-3.522; p = 0.008), RCA lesions (OR 1.797; 95%CI 1.036-3.113; p = 0.037), and conduit strain (OR 0.910; 95%CI 0.868-0.953; p < 0.001) were independent factors for IAB. In model 3, age (OR 1.022; 95%CI 1.001-1.045; p = 0.044), hypertension (OR 2.239; 95%CI 1.329-3.773; p = 0.002), and booster strain (OR 0.948; 95%CI 0.908-0.991; p = 0.019) were independent factors for IAB. With the lowest AIC and BIC values, model 2 was the best-fit model. LA strain associated with IAB in STEMI patients. The model including conduit strain was the best-fit one.

Evaluation of cardiac chamber functions by speckle-tracking echocardiography in the presence of coronary artery flow disturbances other than stenosis: A review

Conditions other than stenosis also disturb the coronary flow. Such conditions include the coronary slow flow phenomenon, coronary artery ectasia, and coronary artery tortuosity. Evidence exists regarding myocardial dysfunction in these conditions. In this review, we present studies that have used speckle-tracking echocardiography to determine whether coronary flow disturbances are accompanied by myocardial dysfunction. Additionally, we seek to show the gaps in knowledge concerning this issue and the dimensions that future studies should consider.

Paced P-wave duration as a significant predictor for atrial high-rate episodes in patients with cardiac implantable electronic devices

BACKGROUND

Atrial pacing can unmask or aggravate a preexisting interatrial block (IAB). The aim of our study was to determine whether atrial pacing is associated with the development of atrial high-rate episodes (AHRE) during follow-up.

METHODS

Patients with dual-chamber cardiac implantable electronic devices (CIED), no previous documented atrial fibrillation, and with a 6-month minimum follow-up were included. In all patients, sinus and paced P-wave duration were measured. AHRE was defined as an episode of atrial rate ≥ 225 bpm with a minimum duration of 5 min, excluding those documented during the first three months after implantation.

RESULTS

Two hundred twenty patients were included (75 ± 10 years, 61% male). After a mean follow-up of 59±25 months, 46% of patients presented AHRE. Mean paced P-wave duration was significantly longer than the sinus P-wave duration (154±27 vs 115±18 ms; p < 0.001). Sinus and paced P-waves were significantly longer in those who developed AHRE (sinus: 119±20 vs 112±16; p  =  0.006; paced: 161±29 vs 148±23; p < 0.001). A paced P-wave ≥160 ms was the best predictor of AHRE, especially those lasting >24 h (OR 4.2 (95% CI) [1.6-11.4]; p  =  0.004).

CONCLUSIONS

Atrial pacing significantly prolongs P-wave duration and is associated with further development of AHRE. A paced P-wave ≥160 ms is a strong predictor of AHRE and should be taken into consideration as a new definition of IAB in the presence of atrial pacing. This article is protected by copyright. All rights reserved.

P Wave Parameters and Indices: A Critical Appraisal of Clinical Utility, Challenges, and Future Research-A Consensus Document Endorsed by the International Society of Electrocardiology and the International Society for Holter and Noninvasive Electrocardiology

Atrial cardiomyopathy, characterized by abnormalities in atrial structure and function, is associated with increased risk of adverse cardiovascular and neurocognitive outcomes, independent of atrial fibrillation. There exists a critical unmet need for a clinical tool that is cost-effective, easy to use, and that can diagnose atrial cardiomyopathy. P wave parameters (PWPs) reflect underlying atrial structure, size, and electrical activation; alterations in these factors manifest as abnormalities in PWPs that can be readily ascertained from a standard 12-lead ECG and potentially be used to aid clinical decision-making. PWPs include P wave duration, interatrial block, P wave terminal force in V₁, P wave axis, P wave voltage, P wave area, and P wave dispersion. PWPs can be combined to yield an index (P wave index), such as the morphology-voltage-P-wave duration ECG risk score. Abnormal PWPs have been shown in population-based cohort studies to be independently associated with higher risks of atrial fibrillation, ischemic stroke, sudden cardiac death, and dementia. Additionally, PWPs, either individually or in combination (as a P wave index), have been reported to enhance prediction of atrial fibrillation or ischemic stroke. To facilitate translation of PWPs to routine clinical practice, additional work is needed to standardize measurement of PWPs (eg, via semiautomated or automated measurement), confirm their reliability and predictive value, leverage novel approaches (eg, wavelet analysis of P waves and machine learning algorithms), and finally, define the risk-benefit ratio of specific interventions in high-risk individuals. Our ultimate goal is to repurpose the ubiquitous 12-lead ECG to advance the study, diagnosis, and treatment of atrial cardiomyopathy, thus overcoming critical challenges in prevention of cardiovascular disease and dementia.