Prediction of atrial fibrillation in patients with hypertension: A comprehensive comparison of office and ambulatory blood pressure measurements

Hypertension is associated with the development of atrial fibrillation (AF). Evidence has shown that reverse dipping pattern, an abnormal increase of night-time blood pressure (BP) comparing to daytime BP, is associated with cardiovascular events. However, the relationship between diurnal changes in BP and AF has not been sufficiently explored. This paper aims to cross-sectionally explore the relationship between AF and ambulatory BP parameters, especially reverse dippers to the others, and further longitudinally analyze how BP patterns are associated to the risk of developing new-onset AF. Between February 2012 and March 2021, five out of 412 patients were identified of AF at baseline; four were reverse dippers (3.7%) and one was from the others (.3%). Cross-sectionally, the multivariate logistic regression analysis showed that reverse dippers were significantly more likely to have AF (odds ratio: 12.39, p = .030). After excluding patients with baseline AF, during the mean follow-up of 4.6 ± 3.0 years, seven patients developed AF. Longitudinally, the multivariate Cox regression analysis revealed that 24-h systolic BP (hazard ratio per 10 mmHg: 2.12, p = .015), night-time systolic BP (hazard ratio per 10 mmHg: 2.27, p = .002), and presentation of reverse dipping (hazard ratio: 5.25, p = .042) were independently associated with new-onset AF. None of the office BP measurements were associated with new-onset AF. While ambulatory BP measurements were better predictors for the incidence of AF, careful management is necessary for reverse dippers as they are at high risk of developing AF.

P-Wave Terminal Force V1 Is Associated with Left Ventricular Diastolic Function in Patients with No Significant Perfusion Abnormality

P-wave terminal force in lead V1 (PTFV1) is a marker of increased left atrial (LA) overload. Whether PTFV1 is associated with left ventricular (LV) diastolic function remains undetermined. We tested the hypothesis that PTFV1 is associated with LV diastolic parameters derived from gated myocardial perfusion single-photon emission computed tomography (SPECT) in patients with no significant perfusion abnormalities.The study population included 158 patients with preserved ejection fraction and no significant perfusion abnormalities. The amplitude and duration of the P-wave negative phase in lead V1 were measured using an electrocardiogram, and PTFV1 was calculated. The peak filling rate (PFR) and one-third mean filling rate (1/3 MFR) were obtained as LV diastolic parameters using gated SPECT.PTFV1 showed a weak correlation with the LA volume index (r = 0.31; P < 0.001). Significant associations were observed between PTFV1 and PFR (r = -0.27; P < 0.001) and 1/3 MFR (r = -0.26; P = 0.001). A multivariate linear regression analysis showed that age (β = -0.26; P < 0.001), LV end-diastolic volume index (β = -0.27; P = 0.001), and PTFV1 (β = -0.15; P = 0.036) were significant factors associated with PFR. Moreover, male gender (β = -0.16; P = 0.041), LV mass index (β = -0.17; P = 0.046), and PTFV1 (β = -0.17; P = 0.022) were significant factors associated with the 1/3 MFR.PTFV1 is associated with LV diastolic function, as derived from gated SPECT in patients with no significant perfusion abnormalities.

Global cognitive function correlates with P-wave dispersion in frail hypertensive older adults

P‐Wave Dispersion (PWD) is an ECG parameter defined as the difference between the longest and the shortest P‐Wave duration. PWD has been associated with hypertension, a leading cause of age‐related cognitive decline. Moreover, hypertension is associated with vascular dementia and Alzheimer's Disease. Based on these considerations, we evaluated PWD and global cognitive function in frail hypertensive older adults with a previous diagnosis of cognitive decline. We evaluated consecutive frail hypertensive patients ≥65‐year‐old with a Mini‐Mental State Examination (MMSE) score <26. Patients with evidence of secondary hypertension, history of stroke, myocardial infarction, or therapy with beta‐blockers or acetylcholinesterase inhibitors were excluded. Beta‐blocker therapy causes a significant decrease in PWD; patients treated with acetylcholinesterase inhibitors were not included to avoid confounding effects on cognitive function. By examining 180 patients, we found that PWD significantly correlated with MMSE score. Strikingly, these effects were confirmed in a linear multivariate analysis with a regression model. To our knowledge, this is the first study showing that PWD correlates with global cognitive function in frail hypertensive older adults.

Vectorial theory surpasses the local theory in explaining the origin of P-wave dispersion

BACKGROUND

Local theory and the vectorial theory are used to explain the origin of P-wave dispersion (PWD). There are no previous studies that analyze both at the same time.

OBJECTIVES

We set out to determine the implication of local and vectorial theories in the origin of PWD.

METHODS

Cross-sectional study in 153 randomly selected patients aged 18-70 years, undergoing electrophysiological study. Inhomogeneous atrial conduction was evaluated by atrial electrogram dispersion in terms of duration (EGM_durdis) and morphology (EGM_morph dis). P-distal coronary sinus interval (P-DCS) was also measured. P-wave was measured twice, firstly at a calibration of 20 mm/mV and a sweep speed of 50 mm/s, enhancement 10× (basic measurement [BM]), and second time at sweep speed of 150 mm/s, enhancement 80-160× (high precision measurement [HPM]).

RESULTS

PWD with BM was 48 ms [36-54 ms] while with HPM it was 4 ms [0-10 ms], p < 0.001. With BM, maximum and minimum P- wave duration presented a moderate correlation (r = 0.342; p < 0.001), using HPM it becomes strong (r = 0.750; p < 0.001). In cases with P-DCS < 80 ms (r = 0.965; p < 0.001), but not with P-DCS ≥ 80 ms (r = 0.649; p < 0.001), the previous correlation became almost perfect with HPM. EGM_durdis and EGM_morphdis were weak but significantly correlated with PWD. This correlation became moderate in patients with P-DCS ≥ 80 ms and disappeared in those with P-DCS, using BM and HPM.

CONCLUSION

Vectorial theory explains almost entirely the PWD phenomenon. Inhomogeneous conduction could be an additional mechanism to explain PWD, but its contribution is small.

Relation of atrial electromechanical delay to P-wave dispersion on surface ECG using vector velocity imaging in patients with hypertrophic cardiomyopathy

OBJECTIVES

Heterogeneity of structural and electrophysiologic properties of atrial myocardium is common characteristic in hypertrophic cardiomyopathy (HCM). We assessed the dispersion of atrial refractoriness on surface ECG using P-wave dispersion (PWD) and its relation to atrial electromechanical functions using vector velocity imaging (VVI) in HCM population.

METHODS

Seventy-nine HCM patients (mean age: 43.7 ± 13 years, 67% male) were compared with 25 healthy individuals as control. P-wave durations, Pmax and Pmin , P-wave dispersion (PWD), and P terminal force (PTF) were measured from 12-lead ECG. LA segmental delay (TTP-d) and dispersion (TTP-SD) of electromechanical activation were derived from atrial strain rate curves.

RESULTS

HCM patients had longer PR interval, PW duration, higher PWD, PTF, QTc compared to control (p < .001). HCM patients were classified according to presence of PWD into two groups, group I with PWD > 46 ms (n = 25) and group II PWD ≤ 46 ms (n = 54). Group I showed higher prevalence of female gender, higher PTF, QTc interval, left ventricular outflow tract (LVOT) obstruction, p < .01, LVOT gradient (p < .001), LV mass index (p < .01), E/E' (p < .01), and severe mitral regurgitation (p < .001). Moreover, PWD was associated with increased atrial electromechanical delay (TTP-d) and LA mechanical dyssynchrony (TTP-SD), p < .001. LA segmental delay and dispersion of electromechanical activation were distinctly higher among HCM patient.

CONCLUSION

PWD is simple ECG criterion, and it is associated with more severe HCM phenotype and LA electromechanical delay while PTF is linked only to atrial remodeling.

New Parameter of the Second Half of the P-Wave, P-Wave Duration, and Atrial Conduction Times Predict Atrial Fibrillation during Electrophysiological Studies

OBJECTIVE

Several P-wave parameters reflect atrial conduction characteristics and have been used to predict atrial fibrillation (AF). The aim of this study was to determine the relationship between maximum P-wave duration (PMax) and new P-wave parameters, with atrial conduction times (CT), and to assess their predictive value of AF during electrophysiological studies (AF-EPS).

SUBJECTS AND METHODS

This was a cross-sectional study in 153 randomly selected patients aged 18-70 years, undergoing EPS. The patients were divided into 2 groups designated as no AF-EPS and AF-EPS, depending on whether AF occurred during EPS or not. Different P-wave parameters and atrial CT were compared for both study groups. Subsequently, the predictive value of the P-wave parameters and the atrial CT for AF-EPS was evaluated.

RESULTS

The values of CT, PMax, and maximum Ppeak-Pend interval (Pp-eMax) were significantly higher in patients with AF-EPS. Almost all P-wave parameters were correlated with the left CT. PMax, Pp-eMax, and CT were univariate and multivariate predictors of AF-EPS. The largest ROC area was presented by interatrial CT (0.852; p < 0.001; cutoff value: ≥82.5 ms; sensitivity: 91.1%; specificity: 81.1%). Pp-eMax showed greater sensitivity (79.5%) to discriminate AF-EPS than PMax (72.7%), but the latter had better specificity (60.4% vs. 41.5%).

CONCLUSIONS

Left atrial CT were directly and significantly correlated with PMax and almost all the parameters of the second half of the P-wave. CT, PMax, and Pp-eMax (new parameter) were good predictors of AF-EPS, although CT did more robustly.

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.

Atrial conduction explains the occurrence of the P-wave dispersion phenomenon, but weakly

BACKGROUND

P-wave dispersion (PWD) is believed to be caused by inhomogeneous atrial conduction. This statement, however, is based on limited little solid evidence. The aim of this study was to determine the relationship between atrial conduction and PWD by means of invasive electrophysiological studies.

METHODS

Cross-sectional study in 153 patients with accessory pathways and atrioventricular node reentry tachycardia (AVNRT) undergoing an electrophysiological study. Different atrial conduction times were measured and correlated with PWD.

RESULTS

Only the interatrial (P-DCS) and left intra-atrial conduction times (ΔDCS-PCS) showed a significant correlation with PWD, but this correlation was weak. Multivariate linear regression analysis determined that both P-DCS (β = 0.242; P = .008) and ΔDCS-PCS (β = 0.295; P < .001) are independent predictors of PWD. Performing the multivariate analysis for arrhythmic substrates, it is observed that only ΔDCS-PCS continued to be an independent predictor of PWD. Analysis of the receiver operating characteristic curves showed that regardless of the types of arrhythmic substrates, PWD discriminates significantly, but moderately, to patients with P-DCS and ΔDCS-PCS ≥75 percentile.

CONCLUSIONS

Interatrial and intraleft atrial conduction times were directly and significantly correlated with PWD, but only weakly, and were independent predictors of PWD. In general, PWD correctly discriminates patients with high values in interatrial and intraleft atrial conduction times, but moderately. This is maintained in cases with accessory pathways; however, in patients with AVNRT it only does so for intraleft atrial conduction times. Interatrial and intraleft atrial conduction times weakly explains PWD.

Left atrial myocardial dysfunction in patients with primary aldosteronism as assessed by speckle-tracking echocardiography

BACKGROUND

We investigated the left atrial myocardial deformation in patients with primary aldosteronism using the speckle-tracking echocardiographic (STE) strain imaging technique.

METHODS

Our study included 107 primary aldosteronism patients [52 aldosterone-producing adenoma (APA) and 55 idiopathic hyperaldosteronism (IHA)] and 50 primary hypertensive patients. We performed conventional echocardiography to measure left atrial volume and ejection fraction, and STE to estimate left atrial myocardial deformation including peak velocity, strain and strain rate and calculate the ratio of E/e' to left atrial strain during left ventricular systole as the left atrial stiffness index.

RESULTS

Patients with APA, compared with those with IHA and primary hypertension had a significantly (P < 0.001) lower serum potassium concentration and higher 24-h urinary aldosterone excretion and plasma aldosterone-to-renin ratio. Patients with APA had a significantly (P < 0.01) larger maximal, precontraction, and minimal left atrial volumes and lower total, active and passive left atrial emptying fractions than those with IHA and primary hypertension. Among the three groups, patients with APA showed lowest left atrial velocity, strain, and strain rate during ventricular systole, early diastole and late diastole (P < 0.05) and highest left atrial stiffness index (P < 0.001). In unadjusted analysis, the left atrial strain, strain rate and stiffness index were significantly (P < 0.05) associated with plasma aldosterone concentration and urinary aldosterone excretion. After adjustment for various confounding factors, these associations remained statistically significant for urinary aldosterone excretion (P < 0.05) but not plasma aldosterone concentration (P ≥ 0.05).

CONCLUSION

Patients with primary aldosteronism, especially APA, had impaired left atrial deformation mechanics and increased left atrial stiffness, providing a promising insight into early detection of subclinical left atrial dysfunction by strain echocardiography.

Determinants of left intra-atrial electromechanical delay as evaluated by tissue Doppler imaging in candidates for coronary artery bypass graft surgery

OBJECTIVES

Inhomogeneity in the atrial conduction time is a predisposing factor for atrial fibrillation. The aim of our study was to determine the independent determinants of the left intra-atrial electromechanical delay (LIAEMD) as a marker of left atrial (LA) dyssynchrony in candidates for coronary artery bypass graft surgery (CABGS).

METHODS

This prospective cross-sectional study recruited 516 consecutive candidates for CABGS. Via the pulsed-wave tissue Doppler imaging modality in echocardiography, the times between the P wave and the peak of the a' wave at the septal and lateral mitral annuli were measured and the difference between these times was considered to be LIAEMD. Additionally, clinical and laboratory data on each patient were gathered. The odds ratio for an increased LIAEMD was calculated in patients with and without diabetes in univariate and multivariate analyses.

RESULTS

The multivariable analysis revealed that in the patients without diabetes, obesity, calcium-channel blocker usage, an increased maximal LA volume, and a decreased lateral e'/a' ratio and in the diabetic patients, diuretic usage and a decreased lateral e'/a' ratio were independently correlated with an increased likelihood of LIAEMD occurrence (P < .05).

CONCLUSIONS

In our study on CABGS candidates, in the patients without diabetes, obesity, an increased maximal LA volume, calcium-channel blocker usage, and a decreased lateral e'/a' ratio and in the diabetic patients, diuretic usage and a decreased lateral e'/a' ratio independently determined increased LIAEMD. The prevention or treatment of factors that are detrimental to the LA electromechanical function may be helpful for the preservation of the LA electromechanical integrity.

Early detection of left atrial dysfunction assessed by CMR feature tracking in hypertensive patients

OBJECTIVES

To evaluate whether early left atrial (LA) dysfunction in hypertension (HTN), with or without left ventricular hypertrophy (LVH), can be detected by cardiovascular magnetic resonance feature tracking (CMR-FT).

METHODS

Seventy-three HTN patients and 29 healthy controls were retrospectively recruited. HTN patients were divided into the LVH (n = 29) and non-LVH group (n = 44). LA performance was analysed using CMR-FT in 2- and 4-chamber cine images, including LA reservoir function (total ejection fraction [EF], total strain [εs], peak positive strain rate [SRs]), conduit function (passive EF, passive strain [εe], peak early negative strain rate [SRe]) and booster pump function (booster EF, active strain [εa], late peak negative strain rate [SRa]). One-way analysis of variance with post hoc LSD tests, Spearman analysis, receiver operating characteristic curve and intra-class correlation coefficient analysis were applied for statistical analyses.

RESULTS

Compared with healthy controls, LA reservoir (LA total EF, εs, SRs) and conduit function (LA passive EF, εe, SRe) were significantly impaired in HTN patients with or without LVH, and these parameters significantly correlated with mitral E/A < 1 (all p < 0.05). However, LA booster pump function was relatively preserved in non-LVH patients, representing an intermediate stage between the LVH group and controls. Among LA deformation parameters, εe showed the highest diagnostic value for differentiation of HTN patients with healthy controls (AUC, 0.82; sensitivity, 80.82%; specificity, 72.41%). Observer reproducibility was good-excellent (ICC, 0.83-0.97) for all CMR-FT derived parameters.

CONCLUSIONS

CMR-FT is a promising tool for quantification of LA function. LA reservoir and conduit dysfunction might be detected early by CMR-FT in HTN patients before the presence of LVH.

KEY POINTS

• CMR-FT is a promising tool in quantifying LA function, including deformation and volumetric parameters. • LA reservoir and conduit dysfunction might be detected early by CMR-FT in HTN patients with or without LVH. • The LA booster pump function was relatively preserved in non-LVH patients.