Predictive value of total atrial conduction time estimated with tissue Doppler imaging for the development of new-onset atrial fibrillation after acute myocardial infarction

Echocardiographic assessment of left atrial appendage morphology and function-an expert proposal by the German Working Group of Cardiovascular Ultrasound

The left atrial appendage is a blind ending cardiac structure prone to blood stasis due to its morphology. This structure is a preferred region of thrombogenesis in relation to reduced myocardial contractility of the atrial wall. Blood stasis occurs primarily in low flow conditions. One of the tasks of echocardiography is the analysis of morphology and function of the left atrial appendage. The detection of thrombi by echocardiography is difficult and must be carried out thoroughly and carefully to avoid potential complications-especially in the context of rhythm control. The assessment of thromboembolic risk, especially in patients with unknown and presumed atrial fibrillation is a second challenge by characterizing atrial function and flow conditions in the left atrial appendage. Thus, this proposal focuses on the obvious problems of echocardiography when assessing left atrial appendage and the role of this method in planning a potential interventional closure of left atrial appendage.

Risk of atrial fibrillation development in adolescent patients with inflammatory bowel disease

There is increasing evidence linking chronic inflammation to the initiation and continuation of atrial fibrillation (AF). Inflammatory bowel diseases (IBD), namely (Crohn's disease (CD) and ulcerative colitis (UC), are chronic systemic inflammatory disorders with both intestinal and extra-intestinal manifestations. Atrial electromechanical delay (EMD) has been known as an early marker of AF. The objective of this study was to evaluate the atrial electromechanical properties in children and adolescents with IBD during remission. One hundred IBD patients aged 12-17 years (50 with CD and 50 with UC) in remission state and 100 healthy controls were recruited for the study. Atrial electromechanical properties were measured using transthoracic echocardiography, tissue Doppler imaging, and simultaneous surface ECG recording. Interatrial EMD, left intra-atrial, and right intra-atrial EMD were calculated. IBD patients in remission state have significantly prolonged left and right intra-atrial EMD and interatrial EMD compared to healthy controls (P = 0.03, P = 0.02, and P = 0.01 respectively). No statistical difference was observed between CD and UC in terms of inter- and intra-atrial EMDs.  Conclusion: Atrial EMD is increased in pediatric patients with IBD indicating the increased risk of AF development. Measurement of atrial EMD parameters might be used to predict the risk of the development of AF in pediatric patients with IBD. What is Known: • There is increasing evidence linking chronic inflammation to the initiation and continuation of atrial fibrillation (AF). • Inflammatory bowel diseases are chronic systemic inflammatory disorders with both intestinal and extra-intestinal manifestations. • Atrial electromechanical delay (EMD) has been reported as an early marker of AF. What is New: • Atrial EMD is increased in pediatric patients with IBD indicating the increased risk of AF development. • Measurement of atrial EMD parameters might be used to predict the risk of the development of AF in pediatric patients with IBD.

Predicting new onset atrial fibrillation post acute myocardial infarction: Echocardiographic assessment of left atrial size

BACKGROUND

Atrial fibrillation (AF) commonly occurs following acute myocardial infarction (AMI). Left atrial (LA) size has been reported to predict new onset AF in this cohort, however, the optimal metric of left atrial size for risk stratification following AMI is unknown.

METHODS

Patients presenting to a tertiary hospital with incident AMI (NSTEMI or STEMI) and no history of AF were recruited. All patients underwent guideline-based workup and management for AMI, including transthoracic echocardiographic assessment. Three alternative metrics of left atrial size were determined: LA area, maximal and minimal LA volume indexed to body surface area (LAVImax and LAVImin). The primary endpoint was new onset AF diagnoses.

RESULTS

Four hundred thirty three patients were included in the analysis, of which 7.1% had a new diagnosis of AF within a median follow-up of 3.8 years. Univariate predictors of incident AF included age, hypertension, revascularization with CABG, NSTEMI presentation, right atrial area, and all three metrics of LA size. Among three multivariable models created for the prediction of new onset AF utilizing alternate metrics of LA size, LAVImin was the only LA size metric found to be an independent predictor.

CONCLUSIONS

LAVImin is an independent predictor of new onset AF post AMI. LAVImin outperforms echocardiographic assessment of diastolic dysfunction and alternative metrics of LA size (including LA area and LAVImax) for risk stratification. Further studies are needed to validate our findings in post AMI patients, and evaluate whether LAVImin holds similar advantages over LAVImax in other cohorts.

Can we explore AF-pacemakers' relationship using clinical and echocardiographic parameters in patients with permanent pacemaker? (Echocardiography and subclinical AF in permanent pacemaker)

Patients on implanted permanent pacemakers frequently develop atrial fibrillation (AF). We aimed to determine the Echocardiographic and clinical parameters predicting AF in patients with a dual-chamber (DDD) pacemaker. This retrospective study included 208 patients with permanent pacemaker, classified according to development of AF during follow up into 2 groups: AF (77, 37%) and non AF (131, 63%), baseline: clinical, ECG(P-wave dispersion) and echo {diastolic wall strain (DWS),left arial volume index (LAVI), left ventricular stiffness index(LVSI)} data were assessed. AF group were older with more P wave dispersion, lesser DWS, greater LVSI& LAVI, LVSI at a cut off > 0.13 and DWS at a cut off < 0.34 were predictors of AF in patients with DDD pacemakers. LVSI and DWS could be used as simple good predictors for AF in patients with DDD pacemakers, for timely initiation of anticoagulants according to CHA₂DS₂VASc score to decrease ischemic stroke burden.

Chronic Obstructive Pulmonary Disease and Risk of Atrial Arrhythmias After ST-Segment Elevation Myocardial Infarction

Background

ST-segment elevation myocardial infarction (STEMI) and cardiac arrhythmias frequently occur in patients with chronic obstructive pulmonary disease (COPD). However, little is known about the association of COPD with the occurrence of atrial arrhythmias after STEMI.

Methods

This retrospective analysis consisted of 320 patients with first STEMI without a history of atrial arrhythmias, with available 24-hour holter-ECG at 3- and/or 6 months follow-up. In total, 80 COPD patients were compared with 240 non-COPD patients, matched by age and gender (mean age 67±10 years, 74% male). Atrial arrhythmias were defined as: atrial fibrillation/flutter, atrial tachycardia (≥3 consecutive premature atrial contractions (PAC's)) and excessive supraventricular ectopy activity (ESVEA, ≥30 PAC's/hour or runs of ≥20 PAC's).

Results

Baseline characteristics were similar among COPD and non-COPD patients regarding infarct location, β-blocker use and cardiovascular risk profile except for smoking (69% vs. 49%, respectively, p=0.002). Additionally, atrial volumes, LVEF and TAPSE were comparable. During 1 year follow-up, a significantly higher prevalence of atrial tachycardia and ESVEA was observed in patients with COPD as compared to non-COPD patients (70% vs. 46%; p<0.001 and 21% vs. 11%; p=0.024, respectively). In multivariate analysis, COPD was independently associated with the occurrence of atrial arrhythmias (combined) during 1 year of follow-up (HR 3.59, 95% CI 1.78-7.22; p<0.001).

Conclusion

COPD patients after STEMI have a significantly higher prevalence of atrial tachycardia and ESVEA within 1 year follow-up as compared to age- and gender matched patients without COPD. Moreover, COPD is independently associated with an increased prevalence of atrial arrhythmias after STEMI.

Echocardiography-derived total atrial conduction time (PA-TDI duration): risk stratification and guidance in atrial fibrillation management

Atrial fibrillation (AF) is a major cause of cardiovascular morbidity and mortality. To early detect and to avoid AF-related complications, several cardiac imaging modalities and approaches aim to quantify the severity of the underlying atrial cardiomyopathy (i.e., the extent of atrial remodeling). However, most established cardiac imaging modalities just incorporate single components of atrial remodeling and do not reflect the complete multifactorial process, which may contribute to their limited predictive value. Echocardiography-derived PA-TDI duration is a sophisticated echocardiographic parameter to assess total atrial conduction time and directly reflects both electrical and structural changes to the atria. Therefore, PA-TDI duration provides a more comprehensive quantification of the extent of atrial remodeling than other imaging modalities. In this article we review the role of PA-TDI duration as a marker of atrial remodeling and summarize the available data on PA-TDI duration to identify patients at risk for AF, as well as to guide AF management. Moreover, we discuss how to assess PA-TDI duration and provide recommendations on the implementation of PA-TDI duration into routine clinical care.

Atrial conduction time associated predictors of recurrent atrial fibrillation

Identifying patients at high risk of atrial fibrillation (AF) recurrence remains challenging. This study aimed to evaluate total atrial conduction time (TACT) and left atrial (LA) asynchrony as predictors of AF recurrence. Consecutive patients after the first AF episode, terminated either spontaneously or with cardioversion, underwent transthoracic echocardiography. TACT, estimated by the time delay between the onset of P-wave and the peak A'-wave on the Tissue Doppler Imaging (PA-TDI duration), atrial volumetric and functional parameters, and biatrial strain were assessed. We calculated mean PA-TDI-the average of PA-TDI measurements in all left atrial (LA) walls-and the difference between the longest and the shortest PA interval (DLS) and the standard deviation of 4 PA intervals (SD4) to assess the LA global remodeling and asynchrony, respectively. The primary endpoint was AF recurrence. Patients with recurrent AF had significantly prolonged PA-TDI intervals in each LA wall-and thus mean PA-TDI-than those without recurrence (mean PA-TDI: 157.4 ± 17.9 vs. 110.2 ± 7.7 ms, p < 0.001). At univariate analysis, LA maximum volume index, total LA emptying fraction, right atrial maximum volume index, PA-TDI, DLS, and SD4 were predictors of AF recurrence. At multivariable analysis, PA-TDI intervals in all LA walls remained strong predictors with mean PA-TDI (odds ratio 1.04; 95% confidence interval 1.03-1.06) having an optimal cutoff of 125.8 ms in receiver operator characteristics curve analysis providing 98% sensitivity and 100% specificity for AF recurrence (area under the curve = 0.989). PA-TDI was an independent predictor of AF recurrence and outperformed established echocardiographic parameters.

Coronary heart disease and atrial fibrillation: a vicious cycle

The population suffering from coronary heart disease (CHD) complicated by atrial fibrillation (AF) is rising rapidly. A strong correlation between the two diseases has been reported, and the many common risk factors they share may play prominent roles in their development. In addition, CHD can directly promote the progression of AF by affecting reentry formation, focal ectopic activity, and neural remodeling. At the same time, AF also affects CHD through three aspects: 1) atherosclerosis, 2) the mismatch of blood supply and oxygen consumption, and 3) thrombosis. In conclusion, CHD and AF can aggravate each other and seem to form a vicious cycle. For patients with CHD complicated by AF, principal studies and guidelines have focused on antithrombotic treatment and rhythm control, which are paramount for these patients. Of note, our review sheds light on the strategies to break the cycle of the two diseases, which may be fundamental to treat these patients and optimize the benefit.

Agreement Between Electrophysiology Study and Tissue Doppler Imaging Regarding the Measurement of Total Atrial Conduction Time and Left Atrial Conduction Delay

The aim of our study was to evaluate the agreement between tissue Doppler imaging (TDI) methods and electrophysiology study (EPS) concerning the measurement of total atrial conduction time (TACT) and left atrial conduction delay (LACD). Sixty-nine candidates for EPS were included. TACT and LACD were measured in the EPS. The TDI time intervals for each patient were measured using both pulsed-wave (PW) and 2-D color-coded (CC) methods, once from the beginning of the P wave to the beginning of the a' wave (Tb) and once again to the peak of the a' wave (Tp) at the mitral annulus. TACT and LACD measured by TDI were not in good agreement with those measured by EPS. There was moderate agreement between PW-Tb and CC-Tb and good agreement between PW-Tp and CC-Tp for the measurement of TACT; nevertheless, agreement was not good in the case of LACD.

Novel Echocardiographic Biomarkers in the Management of Atrial Fibrillation

Purpose of Review

Atrial fibrillation (AF) is the most common arrhythmia in adults. The number of patients with AF is anticipated to increase annually, mainly due to the aging population alongside improved arrhythmia detection. AF is associated with a significantly elevated risk of hospitalization, stroke, thromboembolism, heart failure, and all-cause mortality. Echocardiography is one of the key components of routine assessment and management of AF. Therefore, the aim of this review is to briefly summarize current knowledge on “novel” echocardiographic parameters that may be of value in the management of AF patients.

Recent Findings

Novel echocardiographic biomarkers and their clinical application related to the management of AF have been taken into consideration. Both standard parameters such as atrial size and volume but also novels like atrial strain and tissue Doppler techniques have been analyzed.

Summary

A number of novel echocardiographic parameters have been proven to enable early detection of left atrial dysfunction along with increased diagnosis accuracy. This concerns particularly experienced echocardiographers. Hence, these techniques might improve the prediction of stroke and thromboembolic events among AF patients and need to be further developed and disseminated. Nonetheless, even the standard imaging parameters could be of significant value and should not be discontinued in everyday clinical practice.

Comparison of atrial fibrillation predictors in patients with acute coronary syndrome using ticagrelor or clopidogrel

Background/aim

Ticagrelor is a drug widely used in patients with acute coronary syndromes (ACS) that specifically increases the plasma level of adenosine, which is likely to cause atrial fibrillation (AF). Therefore, in this study we aimed to investigate the electrocardiographic and echocardiographic predictors of AF development after P2Y12 receptor antagonists in ACS patients.

Materials and methods

This cross-sectional study included 831 patients with ACS (486 [58.5%] with ST elevated myocardial infarction [STEMI] and 345 [41.5%] with non-ST elevated myocardial infarction [NSTEMI]). Patients were divided into ticagrelor (n = 410) and clopidogrel (n = 421) groups. P wave properties including P wave dispersion and atrial electromechanical conduction properties were measured as AF predictors with surface ECG and tissue Doppler imaging.

Results

Baseline characteristics such as age, sex, heart rate, blood pressure, and laboratory parameters were almost the same in the ticagrelor and clopidogrel groups. The statistical analysis showed no significant difference in P wave dispersion (PWD) between ticagrelor and clopidogrel groups (40.98 ± 12 ms versus 40.06 ± 12 ms, P = 0.304). Subgroups analysis according to ACS types also showed no significant difference in PWD (NSTEMI: 41.16 ± 13.8 ms versus 40.76 ± 13.55 ms, P = 0.799; STEMI: 40.9 ± 12.62 ms versus 39.19 ± 11.18 ms, P = 0.132). In addition, we did not find significant difference in atrial electromechanical delay (EMD) with tissue Doppler imaging (interatrial EMD 24.11 ± 3.06 ms versus 24.46 ± 3.23 ms, P = 0.279).

Conclusion

In conclusion, we did not find any difference in detailed electrocardiographic and echocardiographic parameters as AF predictors between ticagrelor and clopidogrel groups in patients with ACS

Tissue Doppler-derived atrial dyssynchrony predicts new-onset atrial fibrillation during hospitalization for ST-elevation myocardial infarction

BACKGROUND

Atrial dyssynchrony, but not atrial enlargement/dysfunction, reflects acute atrial histopathological changes. It has been shown to be associated with new-onset atrial fibrillation (NOAF) in various clinical conditions but was not studied in the acute phase of ST-elevation myocardial infarction (STEMI) which is the aim of the current study.

METHODS

A total of 440 STEMI patients underwent primary percutaneous coronary intervention (PCI) and were monitored for NOAF during hospitalization. Immediately after primary PCI, P-wave dispersion was calculated and conventional/tissue Doppler echocardiography was done.

RESULTS

During a median hospitalization period of 3 days, 80 (18.2%) patients developed NOAF. The group with NOAF showed significantly higher prevalence of hypertension (P = .049), higher P-wave dispersion (P = .018), higher post-PCI-corrected TIMI frame count (P < .001), and lower incidence of post-PCI myocardial blush grade 2-3 (P = .031). Indexed left atrial maximum volume (LAVI_max ), left atrial dyssynchrony, and inter-atrial dyssynchrony were significantly higher in NOAF group (P < .001, each). Using ROC curve analysis, inter-atrial dyssynchrony showed the highest diagnostic performance (AUC 85%, 95% CI: 0.77-0.94, P < .001). A cutoff value at 23.8 ms showed a good validity for predicting NOAF with a sensitivity of 93.8% and a specificity of 68.1%. Using binary logistic regression analysis, history of hypertension (OR = 10.72, P = .03), LAVI_max (OR = 7.47, P = .04), and inter-atrial dyssynchrony (OR = 45.58, P = .001) were independent determinants of NOAF.

CONCLUSIONS

In the acute phase after STEMI, history of hypertension, LAVI_max, and inter-atrial dyssynchrony were independent determinants of inhospital NOAF, with the latter being the strongest.

Early Versus Late New-Onset Atrial Fibrillation in Acute Myocardial Infarction: Differences in Clinical Characteristics and Predictors

New-onset atrial fibrillation (NOAF) during acute myocardial infarction (AMI) has significant consequences but is often misdiagnosed. The aim of the study was to evaluate predictors of NOAF throughout different phases of AMI. Patients with AMI admitted to a tertiary medical center were analyzed. Exclusion criteria were preexisting AF, AMI onset ≥24 hours prior to admission, in-hospital death, significant valvular disease, and in-hospital coronary artery bypass graft. Study population were AMI without-NOAF, early-AF (AF terminated within 24 hours of admission), and late-AF (beyond the first 24 hours). Overall 5946 patients were included, age: 64.8 ±14.8 years; 30% women. The incidence of NOAF was 4.6%: 1.6% early-AF, and 3% late-AF. Patients with NOAF comprised greater rate of women, cardiovascular risk-factors burden, severe left ventricular-dysfunction, pulmonary hypertension, valvular disorders, and left atrial enlargement compared with patients without-NOAF. Non-ST-elevation myocardial infarction and inferior-ST-elevation myocardial infarction (STEMI) were significantly more prevalent among early-AF group, while anterior-STEMI, in late-AF. The final multivariate models showed c-statistics of 0.73 and 0.76 for the prediction of new-onset early-AF and late-AF, respectively. In conclusion, there are different clinical predictors of early- versus late-NOAF. The study points out “high risk” AMI population for more meticulous heart rate monitoring for NOAF.

Septal total atrial conduction time for prediction of atrial fibrillation in embolic stroke of unknown source: a pilot study

BACKGROUND

Subclinical atrial fibrillation (AF) is the underlying cause in a relevant part of patients with embolic stroke of unknown source (ESUS). This pilot study aims to identify novel echocardiographic parameters predicting AF subsequently detected in patients originally hospitalized with ESUS.

METHODS AND RESULTS

Patients with acute ischemic stroke [baseline diagnosis of ESUS (n = 69), stroke of macro- or microvascular cause (n = 16/25), stroke caused by AF (n = 5)] and controls with paroxysmal AF without acute ischemic stroke (n = 22) as well as healthy controls of young and old age (n = 21/17) in sinus rhythm were included (overall n = 175). Echocardiography was performed in all participants. Prolonged Holter-ECG-monitoring was performed in all stroke patients. In the overall cohort, septal total atrial conduction time (sPA-TDI), left atrial (LA) volume index to tissue Doppler velocity (LAVI/a`) and second negative peak strain rate during LA contraction (SRa), representing echocardiographic parameters of LA remodelling and function, were statistically significant different in patients with and without AF and predictive for subclinical AF (multivariate regression analysis: sPA-TDI: HR 1.06 [1.04-1.08], p < 0.001; LAVI/a`: HR 0.85, [0.74-0.97], p = 0.02; SRa: HR 2.35 [0.9-5.5], p = 0.05). Multivariate Cox regression analysis revealed sPA-TDI as an independent predictor of AF in ESUS patients (sPA-TDI: HR 1.10 [1.04-1.17], p = 0.001). A sPA-TDI of 126 ms strictly discriminated between presence and absence of subclinical AF within 48 h after initiation of Holter-ECG-monitoring in ESUS patients.

CONCLUSIONS

sPA-TDI seems to be a strong independent predictor of subclinical AF in patients hospitalized for ESUS and might support risk-stratified clinical decision making in these patients. Septal Total Atrial Conduction Time (sPA-TDI) determined by echocardiography for prediction of Atrial Fibrillation in Embolic Stroke of Unknown Source (ESUS).

Atrial electromechanical delay assessment in early phase after catheter ablation for patients with atrial fibrillation

BACKGROUND

Variation of atrial electromechanical delay (AED) in early phase after catheter ablation in patients with atrial fibrillation (AF) is lacking.

METHODS

Fifty-five consecutive patients restored sinus rhythm after ablation was included. Echocardiography was performed at 4 h, 1 day, and 3 days after radiofrequency catheter ablation, and AED was measured simultaneously by echocardiography with pulse Doppler imaging and pulse wave tissue Doppler imaging.

RESULTS

AED parameters were significantly longer in the nonparoxysmal atrial fibrillation (NPAF) group than in the paroxysmal atrial fibrillation (PAF) group at each checking point after ablation (P < 0.05). Compared with other checking points, AED parameters were significantly longer 4 h postablation in the NPAF group, while no significant difference was found between different checking points in the PAF group. AED-leap, representing the variation of AED in NPAF patients, was significantly positively correlated with the duration of NPAF (r = 0.5291, P = 0.0113).

CONCLUSIONS

Compared with PAF, NPAF patients have a longer AED postablation, and an abrupt decrease in the initial-h postablation. Such phenomenon gives rise to the different clinical features of PAF and NPAF, and could guide different assessment and treatment strategies for different types of AF.

Evaluation of Atrial Electromechanical Delay to Predict Atrial Fibrillation in Hemodialysis Patients

Background and objective: Prevalence of atrial fibrillation is higher in hemodialysis patients as compared to the general population. Atrial electromechanical delay is known as a significant predictor of atrial fibrillation. In this study, we aimed to reveal the relationship between atrial electromechanical delay and attacks of atrial fibrillation. Materials and methods: The study included 77 hemodialysis patients over 18 years of age giving written consent to participate in the study. The patients were divided into two groups based on the results of 24-h Holter Electrocardiogram (Holter ECG) as the ones having attacks of atrial fibrillation and the others without any attack of atrial fibrillation. Standard echocardiographic measurements were taken from all patients. Additionally, atrial conduction times were measured by tissue Doppler technique and atrial electromechanical delays were calculated. Results: Intra- and interatrial electromechanical delay were found as significantly lengthened in the group of patients with attacks of atrial fibrillation (p = 0.03 and p < 0.001 respectively). The optimal cut-off time for interatrial electromechanical delay to predict atrial fibrillation was >21 ms with a specificity of 79.3% and a sensitivity of 73.7% (area under the curve 0.820; 95% confidence interval (CI), 0.716⁻0.898). In the multivariate logistic regression model, interatrial electromechanical delay (odds ratio = 1.230; 95% CI, 1.104⁻1.370; p < 0.001) and hypertension (odds ratio = 4.525; 95% CI, 1.042⁻19.651; p = 0.044) were also associated with atrial fibrillation after adjustment for variables found to be statistically significant in univariate analysis and correlated with interatrial electromechanical delay. Conclusions: Interatrial electromechanical delay is independently related with the attacks of atrial fibrillation detected on Holter ECG records in hemodialysis patients.

Echocardiographic associates of atrial fibrillation in end-stage renal disease

Background

The prevalence of atrial fibrillation (AF) in end-stage renal disease (ESRD) patients is relatively high. The present study evaluated the association between left atrial (LA) remodelling, including an increased size and myocardial fibrosis, and slow LA conduction and the occurrence of AF.

Methods

In 171 ESRD patients enrolled in the Implantable Cardioverter Defibrillators in Dialysis patients (ICD2) trial, the LA dimensions, LA conduction delay [as reflected by the time difference between P-wave onset on surface electrocardiogram and A'-wave on tissue Doppler imaging (PA-TDI)] and LA function were compared between patients who exhibited AF versus patients without AF. Based on ICD remote monitoring or clinical records, the occurrence of AF was detected.

Results

Of 171 patients, 47 (27%) patients experienced AF. Despite comparable left ventricular ejection fraction and prevalence of significant mitral regurgitation, patients with AF had significantly larger LA volume index (mean ± standard deviation) (29 ± 11 versus 23 ± 10 mL/m2, P = 0.001), longer PA-TDI duration (144 ± 30 versus 131 ± 27 ms, P = 0.010) and reduced late diastolic mitral annular velocity (A') (7.1 ± 2.8 versus 8.2 ± 2.4 cm/s, P = 0.012) compared with patients without AF. On multivariable analysis, larger LA volume index [odds ratio (OR) 1.04, 95% confidence interval (CI) 1.01-1.08, P = 0.017], longer PA-TDI duration (OR 1.02, 95% CI 1.00-1.03, P = 0.025) and reduced A' (OR 0.84, 95% CI 0.72-0.98, P = 0.025) were independently associated with AF after adjusting for age and left ventricle diastolic relaxation.

Conclusion

ESRD patients with AF show more advanced changes in the LA substrate than ESRD patients without AF.

The role of the atrial electromechanical delay in predicting atrial fibrillation in beta-thalassemia major patients

BACKGROUND

Paroxysmal atrial tachyarrhythmias frequently occur in beta-thalassemia major (β-TM) patients. The aim of the current study was to evaluate the atrial electromechanical delay (AEMD) in a large β-TM population with normal cardiac function and its relationship to atrial fibrillation (AF) onset.

METHODS

Eighty β-TM patients (44 men, 36 women), with a mean age of 36.2 ± 11.1 years, and 80 healthy subjects used as controls, matched for age and gender, were studied for the occurrence of AF during a 5-year follow-up, through 30-day external loop recorder (ELR) monitoring performed every 6 months. Intra-AEMD and inter-AEMD of both atria were measured through tissue Doppler echocardiography. P-wave dispersion (PD) was carefully measured using 12-lead electrocardiogram (ECG).

RESULTS

Compared to the healthy control group, the β-TM patients showed a statistically significant increase in inter-AEMD, intra-left AEMD, maximum P-wave duration, and PD. Dividing the β-TM group into two subgroups (patients with or without AF), the inter-AEMD, intra-left AEMD, maximum P-wave duration, and PD were significantly higher in the subgroup with AF compared to the subgroup without AF. There were significant good correlations of intra-left AEMD and inter-AEMD with PD. A cut-off value of 40.1 ms for intra-left AEMD had a sensitivity of 76.2% and a specificity of 97.5% in identifying β-TM patients with AF risk. A cut-off value of 44.8 ms for inter-AEMD had a sensitivity of 81.2% and a specificity of 98.7% in identifying this category of patients.

CONCLUSIONS

Our results showed that the echocardiographic atrial electromechanical delay indices (intra-left and inter-AEMD) and the PD were significantly increased in β-TM subjects with normal cardiac function. PD and AEMD represent non-invasive, inexpensive, useful, and simple parameters to assess the AF risk in β-TM patients.

Global longitudinal strain predicts incident atrial fibrillation and stroke occurrence after acute myocardial infarction

Patients with acute myocardial infarction are at increased risk of developing atrial fibrillation. We aimed to evaluate whether speckle tracking echocardiography improves risk stratification for atrial fibrillation in these patients.The study comprised of 373 patients with ST-segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention. Patients had an echocardiogram performed at a median of 2 days after their STEMI. The echocardiograms consisted of conventional measurements and myocardial strain analysis by speckle tracking from 3 apical projections. The endpoint was a composite of new-onset atrial fibrillation and ischemic stroke. At a median follow-up time of 5.5 years (interquartile range 4.9, 6.1 years), 44 patients developed the endpoint (atrial fibrillation: n = 24, ischemic stroke: n = 24, both: n = 4). Patients who reached the endpoint had significantly reduced systolic function by the left ventricular ejection fraction (LVEF) (43% vs 46%; P = 0.042) and global longitudinal strain (10.9% vs 12.6%; P = 0.004), both being univariable predictors. However, only global longitudinal strain remained a significantly independent predictor (hazard ratio 1.12, 95% confidence interval 1.00; 1.25, P = 0.042, per 1% decrease) after multivariable adjustment for baseline predictors (age, sex, diabetes, hypertension, diastolic dysfunction, and LVEF) using Cox regression. Furthermore, global longitudinal strain resulted in significantly higher c-statistics for prediction of outcome compared with LVEF <45% (0.63 vs 0.52; P = 0.026). When stratified into tertiles of global longitudinal strain, it became evident that patients in the lowest tertile mediated this signal with a 2-fold increased risk compared with the highest tertile (hazard ratio 2.10, 95% confidence interval 1.04; 4.25).Global longitudinal strain predicts atrial fibrillation after STEMI and may add valuable information which can help facilitate arrhythmia detection in these patients.

Atrial Electromechanical Properties in Inflammatory Bowel Disease

BACKGROUND

There is much evidence linking inflammation to the initiation and continuation of atrial fibrillation (AF). Inflammatory bowel diseases (IBD), including ulcerative colitis (UC) and Crohn's disease (CD), are chronic systemic inflammatory disorders. Atrial electromechanical delay (EMD) has been known as an early marker of AF. The objectives of this study were to evaluate the atrial electromechanical properties in patients with IBD.

METHODS

Fifty-two patients with IBD and 26 healthy controls were recruited in the study. Twenty-five of patients with IBD were on active period, and the remaining 27 were on remission period. Atrial electromechanical properties were measured by using transthoracic echocardiography and tissue Doppler imaging and simultaneous surface ECG recording. Interatrial EMD, left intraatrial EMD, and right intraatrial EMD were calculated.

RESULTS

Patients on activation with IBD had significantly prolonged left and right intraatrial EMDs and interatrial EMD compared to patients on remission (P = 0.048, P = 0.036, P < 0.001, respectively) and healthy controls (P < 0.001, for all comparisons). Left and right intraatrial EMDs and interatrial EMD were also found to be higher when patients on remission with IBD compared with healthy controls. No statistical difference was observed between UC and CD in terms of inter- and intraatrial EMDs.

CONCLUSIONS

Atrial electromechanical conduction is prolonged in IBD, and exposure to chronic inflammation may lead to structural and electrophysiological changes in the atrial tissue that causes slow conduction. Measurement of atrial EMD parameters might be used to predict the risk for the development of AF in patients with IBD.

Total atrial conduction time to predict occult atrial fibrillation after cryptogenic stroke

BACKGROUND

Insertable cardiac monitor (ICM) increases the detection rate of occult atrial fibrillation (AF) after cryptogenic stroke. The aim of this study was to evaluate the prognostic significance of total atrial conduction time (TACT) assessed by tissue Doppler imaging (PA-TDI interval) to predict AF presence in patients with cryptogenic stroke.

METHODS

Ninety patients (57.7 ± 12.3 years, 48 % women) after acute cryptogenic stroke and ICM implantation were prospective recruited at four centers for continuous rhythm monitoring. In all patients, TACT was measured by PA-TDI interval via echocardiography. Patients were followed up (331 ± 186 days) for detection of AF (defined by episode lasting ≥30 s).

RESULTS

AF was detected in 16 patients (18 %) during follow-up (331 ± 186 days). The median period to AF detection was 30 days (q1-q3; 16-62 days). Patients who exhibited occult AF were characterized by significantly longer PA-TDI intervals (154.7 ± 12.6 vs. 133.9 ± 9.5 ms, p < 0.0001). The cut-off value of PA-TDI interval at 145 ms demonstrated sensitivity and specificity for AF detection of 93.8 and 90.5 %, respectively. In multivariate analysis, CHA2DS2-VASc score (HR 1.96 per 1 point, p < 0.01) and longer PA-TDI interval (HR 4.05 per 10 ms, p < 0.0001) were independent predictors of occult AF.

CONCLUSION

Our data suggest that measurement of TACT could help to predict future AF detection in patients with cryptogenic stroke. The clinical importance of prolonged rhythm monitoring or indication of direct anticoagulation therapy after cryptogenic stroke based on TACT should be further investigated.

Impact of Continuous Positive Airway Pressure Therapy on Atrial Electromechanical Delay in Obesity-Hypoventilation Syndrome Patients

BACKGROUND

Obesity-hypoventilation syndrome (OHS) is defined as daytime hypercapnia and hypoxemia in obese patients with sleep-disordered breathing. We evaluated the electrocardiographic P-wave duration and dispersion (PD) and echocardiographic noninvasive indicators of atrial conduction heterogeneity in OHS patients and the impact of CPAP on atrial conduction and atrial fibrillation incidence.

METHODS AND RESULTS

We enrolled 50 OHS patients and 50 sex- and age-matched obese subjects as control. Study population underwent cardiologic evaluation and polysomnography before enrollment, at 1- and 6-month follow-ups after CPAP therapy. The OHS group showed a significant increase in inter-atrial (35.2 ± 8 milliseconds vs. 20.1 ± 2.7 milliseconds, P < 0.0001), intra-left (30.5 ± 7.2 milliseconds vs. 16.5 ± 2 milliseconds, P < 0.0001), and intra-right atrial electromechanical delays (AEMD)(24.8 ± 10 milliseconds vs. 15 ± 2.6 milliseconds, P < 0.0001) as well as in Pmax (130 ± 7.4 milliseconds vs. 97 ± 7.2 milliseconds, P = 0.002) and PD (56.5 ± 8.5 milliseconds vs. 31 ± 7.2 milliseconds, P = 0.002) compared to the control group. Significant improvement was noted after 6 months of CPAP therapy in inter-atrial (35.2 ± 8 milliseconds vs. 24.5 ± 6.3 milliseconds, P < 0.0001), intra-left (30.5 ± 7.2 milliseconds vs. 20.6 ± 5 milliseconds, P = 0.003), and intra-right AEMD (24.8 ± 10 milliseconds vs. 17 ± 7.5 milliseconds, P < 0.0001), as well as in Pmax (130 ± 7.4 milliseconds vs. 95 ± 10 milliseconds, P < 0.0001) and in PD (56.5 ± 8.5 milliseconds vs. 32.5 ± 6 milliseconds, P < 0.0001) in the OHS group. External loop recorder monitoring detected paroxysmal AF in 19 OHS patients (38%) with significant reduction in paroxysmal AF episodes (12 ± 6 vs. 47 ± 12, P < 0.0001) after 6-month CPAP therapy.

CONCLUSION

Our findings showed a significant increase of electrocardiographic and echocardiographic indexes of atrial conduction heterogeneity in OHS patients. The CPAP therapy, having a positive impact on atrial conduction time, seems to reduce AF incidence in OHS patients.

Electrophysiological validation of total atrial conduction time measurement by tissue doppler echocardiography according to age and sex in healthy adults

Background

We sought to validate total atrial conduction time (TACT) measurement via tissue Doppler imaging (TDI) by comparing the electrophysiological study (EPS) measurements of healthy subjects, according to age and sex.

Methods

Eighty patients with normal EPS results were included. TACT was measured by EPS and TDI. For validation, the results of TDI were compared with those of EPS. TACT was assessed by measuring the time interval between the beginning of the P-wave on the surface ECG, and the peak A-wave on TDI from the left atrial lateral wall, just over the mitral annulus. Electrophysiological TACT was defined as the time from the high right atrial electrogram to the distal coronary sinus atrial electrogram around the left lateral portion of the mitral ring.

Results

EPS and TDI measurements of the TACT were significantly and positively correlated among men and women in 20–30 years (p=0.008, r=0.412; p>0.001, r=0.706, respectively), and those in the 30–40 years group (p=0.001, r=0.649; p=0.001, r=0.696). In contrast, EPS and TDI measurements of TACT were not significantly different among men and women in the 20–30 years and those in the 30–40 years group (p>0.05, for both). On univariate regression analyses, TACT was independently associated with age (β=0.342, =0.001).

Conclusions

When assessed according to the age and sex of healthy participants, TDI and EPS measurements during TACT assessments were similar and correlated with each other. The measurement of TACT via TDI may be used accurately and confidently than the measurement via EPS in healthy individuals.

Atrial Septal Aneurysms and Supraventricular Arrhythmias: The Role of Atrial Electromechanical Delay

BACKGROUND

Paroxysmal supraventricular arrhythmias (SVAs) frequently occur in patients with atrial septal aneurysm (ASA). The aim of the current study was to evaluate the electrocardiographic (P-wave duration and dispersion) and echocardiographic (atrial electromechanical delay, AEMD) noninvasive indicators of atrial conduction heterogeneity in healthy ASA subjects without interatrial shunt and to assess the AEMD role in predicting the SVAs onset in this population.

MATERIALS AND METHODS

One hundered ASA patients (41 males, mean age of 32.5 ± 8 years) and 100 healthy subjects used as controls, matched for age and gender, were studied for the occurrence of SVAs during a 4-year follow-up, through 30-day external loop recorder (ELR) monitoring performed every 3 months. ASAs were diagnosed by transthoracic echocardiography based on the criteria of a minimal aneurismal base of ≥15 mm and an excursion of ≥10 mm. Intra-AEMD and inter-AEMD of both atria were measured through tissue Doppler echocardiography. P-wave dispersion (PD) was carefully measured using 12-lead electrocardiogram (ECG).

RESULTS

Compared to the healthy control group, the ASA group showed a statistically significant increase in inter-AEMD, intra-left AEMD, maximum P-wave duration, and PD. Dividing the ASA group into 2 subgroups (patients with or without SVAs), the inter-AEMD, intra-left AEMD, P max, and PD were significantly higher in the subgroup with SVAs compared to the subgroup without SVAs. There were significant good correlations of intra-left AEMD and inter-AEMD with PD. A cutoff value of 40.1 msec for intra-left AEMD had a sensitivity of 82% and a specificity of 83% in identifying ASA patients at risk for SVA.

CONCLUSION

Our results showed that the echocardiographic AEMD indices (intra-left and inter-AEMD) and the PD were significantly increased in healthy ASA subjects without interatrial shunt. PD and AEMD represent noninvasive, inexpensive, useful, and simple parameters to assess the SVAs' risk in ASA patients.

Effect of left atrium volume on patients' prognosis following acute myocardial infarction

Evaluating left atrium volume is a good way to estimate prognosis in acute myocardial infarction patients because it indicates to time and severity of diastolic dysfunction and longer-term results of acute myocardial infarction. The present study aims at evaluating the effect of left atrium volume on patients' prognosis following acute myocardial infarction. This is a cohort study conducted on 100 patients who were admitted with acute myocardial infarction. They were studied for 9 months and their one-month mortality rate was evaluated. The patients were studied considering demographic factors, risk factors, mechanical and arrhythmic complications and echocardiography indexes such as systolic and diastolic functions and left atrium volume. It was seen that mortality (27.3%, 6.22) in patients with atrium index > 32 mL m(-2) is more than cases with lower atrium index (1.3%, 1.78) (p = 0.001). There was not any meaningful difference in mortality rate of the patients considering age and gender (p > 0.05). This study indicated to lack of any meaningful difference in patients' mortality rate in terms of hypertension, diabetes, smoking and dyslipidemia. But, mortality rate was significantly higher in MI as a result of elevated-ST, diastolic dysfunction, restrictive pattern, ejection fraction of left atrium < 40%, left atrium volume index > 32 mL m(-2). High volume left atrium independently refers to bad prognosis in patients with acute myocardial infarction which is confirmed with outcome clinical predictors and common echocardiography indexes even following modification.

Cilostazol decreases total atrial conduction time in patients with peripheral artery disease

Objective:

Total atrial conduction time (TACT) is the most important parameter in predicting the development of new-onset atrial fibrillation. We investigated the effect of cilostazol therapy on TACT in patients with peripheral artery disease.

Methods:

Thirty patients with peripheral artery disease were treated with cilostazol (200 mg/day) for 6 months. The baseline echocardiographic total atrial conduction time parameter was compared with the 6-month follow-up.

Results:

The TACT duration was decreased in all patients compared with the baseline after therapy (121.8 ± 19.3 vs. 109.1 ± 15.9 milliseconds, p<0.001). However, left atrial (LA) diameter was not changed with the therapy. The reduction of TACT duration was correlated with the increase in mitral E wave velocity/mitral A wave velocity ratio (r=-0.48, p<0.003).

Conclusion:

Our results showed that 200 mg cilostazol treatment decreased TACT duration in patients with peripheral artery disease, which may also prevent the development and/or recurrence of atrial fibrillation (AF).

Atrial fibrillation in acute ST-elevation myocardial infarction: clinical and prognostic features

Atrial fibrillation (AF) is a common arrhythmia in the setting of acute coronary syndrome and acute ST-elevation myocardial infarction (STEMI). This review summarizes recent evidence on the clinical and prognostic significance of pre-existent and new-onset AF in acute STEMI patients and highlights new emerging predictors of AF development in the era of contemporary treatment.

The Role of Echocardiography as a Predictor of the Incidence and Progression of Atrial Fibrillation

Atrial fibrillation is the most frequent sustained arrhythmia and is an independent risk factor for stroke and death. In recent years, major echocardiographic advances have been made with the development of new techniques and applications that can be extremely useful for the management of these patients. This paper describes the role of echocardiography as a predictor of the incidence and progression of atrial fibrillation. A detailed description of the most relevant studies and recognition of unresolved questions regarding this subject are presented here. A special emphasis will be given on new techniques that allow the assessment of myocardial deformation and their possible role in the way we treat these patients.

Relation of prolonged tissue Doppler imaging-derived atrial conduction time to atrial arrhythmia in adult patients with congenital heart disease

Atrial arrhythmia (AA) is common in adult patients with congenital heart disease (CHD). To enable the prevention of AA or its complications, timely identification of adult patients with CHD at risk of AA is crucial. Long total atrial activation times have been related to AA. Tissue Doppler imaging (TDI) permits noninvasive evaluation of the total atrial conduction time (PA-TDI duration). The present study evaluated the association between the PA-TDI duration and the development of AA in adult patients with CHD. A total of 223 adult patients with CHD were followed up for the occurrence of AA after PA-TDI duration assessment. The PA-TDI duration was defined as the interval from the onset of the P wave on the electrocardiogram to the peak of the A' wave at the lateral atrial wall on TDI tracings. Among the various clinical and echocardiographic parameters, the association between the PA-TDI duration and AA occurrence was investigated. The median follow-up was 39 months (interquartile range 21 to 57). A PA-TDI duration of ≥126 ms was associated with AA during follow-up (log-rank, p <0.001). On multivariate analysis, a PA-TDI duration >126 ms (hazard ratio 2.25, 95% confidence interval 1.21 to 4.19) and history of AA (hazard ratio 4.89, 95% confidence interval 2.75 to 8.71) were independently associated with the occurrence of AA. In conclusion, PA-TDI duration and a history of AA were independently associated with the occurrence of AA in adult patients with CHD. The PA-TDI duration is a useful tool to identify patients with CHD at risk of AA during follow-up.

The effects of spironolactone on atrial remodeling in patients with preserved left ventricular function after an acute myocardial infarction: a randomized follow-up study

OBJECTIVES

Atrial remodeling is an important part of cardiac remodeling after acute myocardial infarction (AMI). The aim of this study was to evaluate the effect of spironolactone on atria in patients with preserved left ventricular (LV) functions after AMI by using two-dimensional and tissue Doppler imaging techniques (TDI).

METHODS

The study consisted of 110 patients with AMI, successfully revascularized with percutaneous coronary intervention, ejection fraction greater than or equal to 40%, and Killip class I-II. Patients were randomized into two groups: conventional therapy (n=55) and additional spironolactone of 25 mg/day with standard conventional therapy (n=55). Echocardiography was performed in the first 48-72 h of AMI and during 6 months of follow-up. Left atrial volume index and emptying fraction were obtained. The peak regional atrial contraction velocity, the time between the onset of p-wave on the monitor ECG and the onset, peak, and the end (TE) of the atrial contraction wave on the tissue Doppler technique curve were measured.

RESULTS

The left atrial volume index and left atrium (LA) dimensions did not significantly change in either group. In the spironolactone group, left atrial emptying fraction increased compared with both baseline value (from 53.0 ± 0.16 to 57.0 ± 0.13 P=0.011) and conventional therapy group (from 50.0 ± 0.17 to 47.0 ± 0.16, P=0.013). The atrial contraction velocity did not change but the LA-TE, interatrial septum-TE, and right atrium-TE were prolonged in the conventional therapy group.

CONCLUSION

Additional spironolactone therapy provided a little benefit on LA remodeling and atrial electromechanic properties in patients with AMI and preserved LV functions.