Independent associations of blood pressure and body mass index with interatrial block: a cross-sectional study in general Chinese population

Cuffless Blood Pressure Measurement Using Linear and Nonlinear Optimized Feature Selection

The cuffless blood pressure (BP) measurement allows for frequent measurement without discomfort to the patient compared to the cuff inflation measurement. With the availability of a large dataset containing physiological waveforms, now it is possible to use them through different learning algorithms to produce a relationship with changes in BP. In this paper, a novel cuffless noninvasive blood pressure measurement technique has been proposed using optimized features from electrocardiogram and photoplethysmography based on multivariate symmetric uncertainty (MSU). The technique is an improvement over other contemporary methods due to the inclusion of feature optimization depending on both linear and nonlinear relationships with the change of blood pressure. MSU has been used as a selection criterion with algorithms such as the fast correlation and ReliefF algorithms followed by the penalty-based regression technique to make sure the features have maximum relevance as well as minimum redundancy. The result from the technique was compared with the performance of similar techniques using the MIMIC-II dataset. After training and testing, the root mean square error (RMSE) comes as 5.28 mmHg for systolic BP and 5.98 mmHg for diastolic BP. In addition, in terms of mean absolute error, the result improved to 4.27 mmHg for SBP and 5.01 for DBP compared to recent cuffless BP measurement techniques which have used substantially large datasets and feature optimization. According to the British Hypertension Society Standard (BHS), our proposed technique achieved at least grade B in all cumulative criteria for cuffless BP measurement.

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

Type 2 diabetes mellitus (T2DM) is one of the most common chronic diseases, and is a risk factor for atrial cardiomyopathy. Interatrial block (IAB), as a predictor of AF, is correlated with the extent of LA fibrosis in the process of atrial cardiomyopathy. We have not encountered any study evaluating LA and LV functions with 3D-STE in the presence of IAB in the T2DM patients. The purpose of the present study was to compare the LA and LV myocardial functions in patients with T2DM with and without IAB by 3D-STE. A total of 175 consecutive patients with T2DM who were examined at outpatient clinics were enrolled in the study (85 patients with IAB and 90 patients without IAB). Surface 12-lead standard electrocardiograms (ECGs) were recorded. Clinical characteristics and laboratory values of the patients were obtained. Conventional 2D echocardiographic and 3D-STE analyses were performed. The mean age of the patients was 59 ± 8.7 years, and 112 (64%) of the patients were female. The LAS-r and LAS-active were significantly decreased in the IAB (+) group than in the IAB (-) group. Statistically significant strong negative linear correlations were observed between P-wave duration and 3D-LA strain values. Our results indicate that there is an impairment in LA myocardial dynamics in the presence of IAB in T2DM patients. According to these findings, we can say that it will be useful to evaluate the LA functions at the preclinical stage in the presence of IAB in patients with T2DM, when considering ischemic cardiovascular and cerebral events.

Assessment of Hypertension Using Clinical Electrocardiogram Features: A First-Ever Review

Hypertension affects an estimated 1.4 billion people and is a major cause of morbidity and mortality worldwide. Early diagnosis and intervention can potentially decrease cardiovascular events later in life. However, blood pressure (BP) measurements take time and require training for health care professionals. The measurements are also inconvenient for patients to access, numerous daily variables affect BP values, and only a few BP readings can be collected per session. This leads to an unmet need for an accurate, 24-h continuous, and portable BP measurement system. Electrocardiograms (ECGs) have been considered as an alternative way to measure BP and may meet this need. This review summarizes the literature published from January 1, 2010, to January 1, 2020, on the use of only ECG wave morphology to monitor BP or identify hypertension. From 35 articles analyzed (9 of those with no listed comorbidities and confounders), the P wave, QTc intervals and TpTe intervals may be promising for this purpose. Unfortunately, with the limited number of articles and the variety of participant populations, we are unable to make conclusions about the effectiveness of ECG-only BP monitoring. We provide 13 recommendations for future ECG-only BP monitoring studies and highlight the limited findings in pregnant and pediatric populations. With the advent of convenient and portable ECG signal recording in smart devices and wearables such as watches, understanding how to apply ECG-only findings to identify hypertension early is crucial to improving health outcomes worldwide.

Coexistence of increased arterial stiffness and interatrial block in overweight subjects

Background

Interatrial block (IAB) is an electrical conduction delay between the right and left atrium and is associated with some cardiovascular disorders. Arterial stiffness is a useful prognostic marker for cardiovascular events. In the present study, we aimed to investigate the coexistence of increased arterial stiffness and IAB in overweight subjects.

Methods

A total of 110 overweight people were enrolled (56 subjects with IAB, and 54 age‐ and gender‐matched subjects without IAB) into the study. Surface 12‐lead standard ECGs were recorded. I.E.M. Mobil‐O‐Graph ambulatory blood pressure monitor device was used to assess the arterial stiffness.

Results

The mean age of the patients was 54.1 ± 11.5 years, and 53.6% were male. PWV and Aix were significantly higher in IAB (+) group than IAB (−) group (9.34 ± 1.5 vs. 7.86 ± 1.3, p < .001; 29.18 ± 11.2 vs. 22.75 ± 10.4, p < .001, respectively), and also, positive linear correlation was observed between arterial stiffness parameters and P‐wave duration (r = .758 for PWV; r = .682 for Aix, respectively).

Conclusion

The present study is the first to focus on evaluating the relationship between the presence of IAB and arterial stiffness in overweight subjects. If there is a coexistence of increased arterial stiffness and IAB in overweight subjects, it should be considered as requiring clinically closer follow‐up.