Tissue velocity Doppler assessment of atrial and ventricular electromechanical coupling and atrioventricular time intervals in normal subjects

Atrial electromechanical delay and p wave dispersion associated with severity of chronic obstructive pulmonary disease

Background

The aim of this study was to evaluate atrial electromechanical delay (AEMD) with both electrocardiography (ECG) and echocardiography in patients with Chronic Obstructive Pulmonary Disease (COPD).

Methods

Total of 110 patients were included in this cross-sectional case-control study. P-wave dispersion (PWD) was measured on a 12-lead ECG. Atrial electromechanical intervals (PA) were measured as the time interval between the onset of the P wave on the ECG and the beginning of the late diastolic A wave.

Results

PWD was found to be 40.9±9.2 ms in the healthy control group, 45.6±8.2 ms in the mild COPD and 44.8±8.7 ms in the severe COPD group (p<0.05). Intra-right atrial EMD was found to be 10.7±5.8 ms in mild COPD, 11.0±7 ms in severe COPD, and it was 16.4±7.3 ms in healthy control group (p<0.001). Interatrial EMD was detected to be 29.5±9.1 ms in the control group, 24.1±9 ms in mild COPD group, and 23.9±11.1 ms in the severe COPD group (p<0.001).

Conclusion

Both mild and severe COPD groups decreased PWD, increased tricuspid PA and significantly decreased interand right intra-AEMD times in comparison to the control group.

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, P_max and P_min, 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, QT_c 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.

The association of inflammatory markers and echocardiographic parameters in Behçet's disease

Background: The main objective of the current study is to find out if any association exists between specific inflammatory markers such as homocysteine (Hcy) and pentraxin-3 (PTX-3) and cardiac involvement determined by means of echocardiographic parameters in patients with Behçet disease (BD).Methods: From January 2011 to January 2012, a total of 62 Behçet's patients were enrolled in the study. Thirty-two healthy subjects constituted the control group. The diagnosis of BD was made as proposed by International Study Group of BD.Results: The mean PTX-3, Hcy, and C-reactive protein levels were significantly higher in patients with BD compared to the control group. The electromechanical delay (EMD) times were found to be prolonged in patients with BD. Also, the aortic stiffness index (SI) and elastic modulus (Ep) were significantly higher, while the aortic dispensibility was significantly lower in patients with BD. The left atrial volume, left atrial volume index, E/A ratio, E/E' septal, IRight-EMD, PA'-ML, PA'-MS, PA'-TL, SI, and Ep were correlated with PTX-3 levels. In addition, the E/A, PA'-ML, PA'-MS, SI, and Ep displayed correlation with Hcy levels in patients having BD.Conclusion: Elevated levels of PTX-3 and Hcy were found to be correlated with cardiac involvement determined by means of echocardiographic parameters in patients with BD.

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.

Acute Effects of Red Bull Energy Drinks on Atrial Electromechanical Function in Healthy Young Adults

Energy drinks (EDs) are widely consumed by adolescents and young adults. Almost all kinds of arrhythmias have been reported following EDs consumption, most of which is atrial fibrillation (AF). Atrial conduction time prolongation and heterogeneous sinusal impulses propagation to the atriums are the key electrophysiological mechanisms leading AF. We aimed to evaluate the acute effects of Red Bull ED ingestion on atrial electromechanical conduction times in healthy young adults. After a 12-hour fasting, 54 healthy young adults consumed 330 mL of Red Bull ED. Atrial electromechanical coupling (PA), intra-atrial electromechanical delay (intra-AEMD), and interatrial electromechanical delay (inter-AEMD) were measured at baseline and 2-hour after Red Bull ED ingestion by echocardiographic tissue-Doppler imaging (TDI) method. PA-lateral (49.7 ± 11.2 vs 54.1 ± 11.0 msn, p = 0.001) and PA-septal (40.8 ± 9.1 vs 43.7 ± 10.5 msn, p = 0.032) times were statistically significantly prolonged after Red Bull ED ingestion. There was also a statistically significant increase in the duration of inter-AEMD (14.4 ± 10.6 vs 18.1 ± 8.5 msn, p = 0.010) after ED ingestion. It was showed that even a single can of ED can acutely increase atrial electromechanical conduction times in young adults. These findings may be the cause of ED-associated AF.

Evaluation of Left Atrial Electromechanical Delay and Left Atrial Phasic Functions in Surgical Early Menopause Patients

BACKGROUND

This study evaluated the atrial electromechanical delay (AEMD) and the left atrial (LA) mechanical functions in patients with surgical early menopause.

METHODS

A total of 62 patients were included in the study: 33 patients with surgical early menopause and 29 age- and sex-matched healthy controls. The duration distance from the start of the P wave to the beginning of the A wave for the lateral mitral annulus, septal mitral annulus, and lateral tricuspid annulus was assessed by tissue Doppler echocardiography. The differences in these durations were used to calculate the inter- and intra-atrial mechanical delays. LA volumes were evaluated using the biplane area-length technique, and LA mechanical function values were measured.

RESULTS

The baseline laboratory and clinical characteristics were similar between the two groups. Surgical early menopause patients displayed increased static atrial electromechanical connection (PA′) times for the septal mitral annulus and lateral tricuspid annulus compared to the controls. However, the lateral mitral annulus, the inter-atrial, the intra-LA, and the right atrial EMD PA′ times were not significantly altered in surgical early menopause patients compared to controls. Importantly, the LA volume index (28.1 ± 8.17 vs. 24.89 ± 7.96 mL/m², p = 0.019), the maximal LA volume (49.6 ± 14.1 vs. 42.9 ± 16.1 mL, p = 0.004), the minimal LA volume (18.4 ± 7.0 vs. 15.2 ± 9.0 mL, p = 0.022), and the atrial precontraction LA volume (31.0 ± 10.9 vs. 24.9 ± 10.1 mL, p = 0.006) were higher in the patients with surgical early menopause compared to the controls. The LA reservoir, conduit and pumping functions and the total, passive, and active emptying volumes were all comparable between the two groups (p = 0.09; 0.06; 0.68; 0.06; 0.48; 0.07, respectively).

CONCLUSIONS

Patients with surgical early menopause demonstrated impaired atrial electrical delay and electromechanical functions.

Relationship of left atrial mechanics to electrical activity on surface electrocardiography in idiopathic dilated cardiomyopathy

Aim: (1) Assess left atrial (LA) mechanics and electromechanical delay in patients with idiopathic dilated cardiomyopathy (IDCM), and (2) examine the relationship between atrial electromechanical delay and atrial electrical activity [P-wave duration, P-wave dispersion (PWD) and P terminal force (PTF)] on surface ECG. Methods: 73 IDCM patients (age 36  ±  17 years); 63% men,25 age & sex matched healthy subjects were studied. LA atrial electromechanical delay & mechanics (ε_sys, SR_sys, SR_e, SR_a) were measured with 2D-strain. From 12-lead electrocardiograms, P-wave duration, PWD and PTF calculated. Results: Reservoir, conduit and contractile functions were predominantly reduced compared to control (P < 0.001). Intra-atrial electromechanical delay was 88.9 ± 84.6 in IDCM versus 27.4 ± 16.5 in control (P < 0.0001). In IDCM, PWD (52.89 ± 15), P_max(98 ± 17.5) and PTF(58.2 ± 36) were significantly increased compared to control (36.20 ± 8.9, 79 ± 9.9, 25.22 ± 8.76) respectively (P < 0.0001). A positive correlation was detected between intra-atrial electromechanical delay and PWD &PTF (r = 0.5, P < 0.0001). By stepwise multiple linear regression analyses, LA reservoir function (LA ε_sys) [β = 0.754; CI at 95%:0.356-0.780, P < 0.001] and LA volume [β = 0.743; CI 95%:0.423-0.75, P < 0.001], and PWD [β=0.848; CI 95%:0.311-0.644, P < 0.0001], and PTF [β = 0.927; CI 95%: 0.357-0.722, P < 0.0001] are independent predictors for LA electromechanical delay in IDCM. Conclusion: In addition to altered LA mechanics, atrial electromechanical delay gets longer in IDCM and is correlated with PWD and PTF. Atrial electrical dispersion on surface ECG could be early index of LA dysfunction that deserves further study.

Noninvasive assessment of left-ventricular diastolic electromechanical coupling in hypertensive heart disease

BACKGROUND

There is a need to stratify patients who may develop heart failure because of the current "heart failure pandemic". We hypothesized that noninvasive assessment of diastolic electromechanical coupling by electrocardiography and Doppler echocardiography may be clinically useful for risk stratification of hypertensive patients who may develop heart failure.

METHODS

We measured the time from the peak to end of the T wave (TpTe) as an electrophysiological parameter, and peak early diastolic mitral flow (E) and lateral annular (e') velocities as mechanical parameters in 109 patients with hypertension. Relationships between these parameters and their association with the prognosis were evaluated.

RESULTS

The e' was inversely correlated with TpTe (p < 0.001) and QTc (p < 0.014), whereas E/e' was positively correlated with TpTe (p < 0.001) and QTc (p < 0.001). The TpTe predicted patients with E/e' > 12. There were 24 cardiovascular events during follow-up (57 ± 20 months), and Kaplan-Meier analysis showed that outcome was worse (p = 0.003) in patients with higher E/e' than lower E/e'; however, there was no difference between patients with longer TpTe (≧72 ms) and shorter TpTe (< 72 ms).

CONCLUSION

The correlation of TpTe with e' and E/e' in hypertensive patients suggests that these parameters reflect diastolic ventricular electromechanical coupling. The E/e' predicted outcome, and an elevated E/e' should be suspected when TpTe is prolonged (> 72 ms). Noninvasive evaluation of diastolic electromechanical coupling is clinically useful in patients with hypertension for predicting their outcome.

Bayes Syndrome and Imaging Techniques

BACKGROUND

Interatrial block (IAB) is due to disruption in the Bachmann region (BR). According to whether interatrial electrical conduction is delayed or completely blocked through the BR, it can be classified as IAB of first, second or third degree. On the surface electrocardiogram, a P wave ≥ 120 ms (partial IAB) is observed or associated to the prolongation of the P wave with a biphasic (positive / negative) morphology in the inferior leads (advanced IAB). Bayes syndrome is defined as an advanced IAB associated with atrial arrhythmia, more specifically atrial fibrillation. Objective and Conclusion: The purpose of this review is to describe the latest evidence about an entity considered an anatomical and electrical substrate with its own name, which may be a predictor of supraventricular arrhythmia and cardioembolic cerebrovascular accidents, as well as the role of new imaging techniques, such as echocardiographic strain and cardiac magnetic resonance imaging, in characterizing atrial alterations associated with this syndrome and generally in the study of anatomy and atrial function.

Cardiac Function and Diastolic Dysfunction in Behcet's Disease: A Systematic Review and Meta-Analysis

Background. Cardiovascular involvement in Behcet's disease (BD) is reported and has variable manifestations. It is not clear if diastolic dysfunction (DD) is increased in BD. Our objective was to evaluate the existing literature to determine if cardiac dysfunction, particularly DD, was more prevalent in these patients. Methods. A systematic review and meta-analysis of the available studies analyzing the echocardiographic findings in BD was conducted using a random-effects model. Mean differences were used to calculate the effect sizes of the echocardiographic parameters of interest. Results. A total of 22 studies with 1624 subjects were included in the analysis. Patients with BD had statistically significantly larger mean left atrial dimension (0.08, p = 0.0008), greater aortic diameter (0.16, p = 0.02), significantly reduced ejection fraction (−1.08, p < 0.0001), significantly prolonged mitral deceleration time (14.20, p < 0.0001), lower E/A ratio (−0.24, p = 0.05), and increased isovolumetric relaxation time (7.29, p < 0.00001). Conclusion. DD is increased in patients with BD by the presence of several echocardiographic parameters favoring DD as compared to controls. The meta-analysis also identified that LA dimension is increased in BD patients. EF has also been found to be lower in BD patients. Aortic diameter was also increased in BD patients as compared to controls.

Immediate effect of percutaneous transvenous mitral commissurotomy on atrial electromechanical delay and P-wave dispersion in patients with severe mitral stenosis

BACKGROUND

Mitral stenosis (MS) is associated with prolonged inter- and intra-atrial electromechanical delays and increased P-wave dispersion, which are markers of atrial fibrillation (AF) risk. This study was conducted to assess the immediate effect of successful percutaneous transvenous mitral commissurotomy (PTMC) on these parameters.

METHODS

This single center observational study included 25 patients with severe MS (aged 34.1 ± 7.1 years, with mean mitral valve area (MVA) of 0.74 ± 0.13 cm(2)), in sinus rhythm, who underwent successful PTMC at our hospital. P-wave dispersion (PWD) was calculated by subtracting minimum P-wave duration (P min) from maximum P-wave duration (Pmax), measured on a 12-lead surface ECG obtained from each patient in supine position at a paper speed of 50mm/s and 20mm/mV. Inter-atrial (AEMD), left intra-atrial (L-IAEMD), and right intra-atrial (R-IAEMD) electromechanical delays were measured on tissue Doppler imaging. PTMC was performed using the standard Inoue Balloon technique. All these parameters were evaluated and compared before and 24-48 h after PTMC.

RESULTS

Successful PTMC led to significant reduction in AEMD (p < 0.001), L-IAEMD (p < 0.001), and R-IAEMD (p < 0.001). There were no changes in Pmax, Pmin, and PWD immediately after PTMC.

CONCLUSIONS

Successful PTMC has a favorable early impact on inter- and intra-atrial electromechanical delays, which are considered as novel parameters of atrial electromechanical remodeling in MS patients. Prospective large-scale studies are required to confirm whether improvement in these markers translates into reduced long-term AF risk.

Evaluating functional capacity, and mortality effects in the presence of atrial electromechanical conduction delay in patients with systolic heart failure

Objective:

Atrial functions are relatively suppressed in heart failure (HF). We aimed to investigate the associations of intra- and inter-atrial electromechanical conduction delay (EMCD) with functional class and mortality over a 12-month follow-up period.

Methods:

The prospective study included 65 patients with systolic HF and 65 healthy subjects with normal sinus rhythm. Left ventricular (LV) systolic functions and left atrial (LA) dimensions and volumes were evaluated by transthoracic echocardiography. Tissue Doppler imaging (TDI) signals at the lateral border of the mitral annulus (lateral PA’), septal mitral annulus (septal PA’), and tricuspid annulus (tricuspid PA’) were measured. Intra- and inter-atrial EMCD were calculated.

Results:

Mitral inflow velocities were studied using pulsed-wave Doppler after placing the sample volume at the leaflets’ tips. The peak early (E wave) and late (A wave) velocities were measured. The septal annular E/E’ ratio was relatively higher and lateral, septal, and right ventricular S, E’, and A’ waves were significantly lower in the HF group than in the control group (12.49±6.03 – 7.16±1.75, pE/E’ <0.0001). Intra-atrial EMCD was detected as 117.5 ms and inter-atrial EMCD as 127.5 ms in patients with prolonged atrial EMCD. A significant increase was found in prolonged intra- and inter-atrial EMCD according to functional capacity increase (p=0.012 and p=0.031, respectively). The incidence of mortality was significantly higher in patients with prolonged atrial EMCD (p=0.025), and 5 patients in the HF group died during the study over the 12-month follow-up period.

Conclusions:

In this study, we found a relationship between prolonged atrial conduction time and increased functional class and mortality in patients with systolic HF. (Anatol J Cardiol 2016; 16: 579-86)

Atrial electromechanical delay is impaired in patients with psoriasis

OBJECTIVE

In this study, we aimed to investigate atrial electromechanical delay (EMD) in patients with psoriasis.

SUBJECTS AND METHODS

A total of 43 patients with psoriasis (26 mild-moderate, 17 severe) and 17 healthy control subjects were enrolled. Patients with psoriasis were divided into two groups: the mild-moderate group and the severe group according to their psoriasis area severity index (PASI) scores. Atrial EMD was measured from the lateral mitral annulus and called 'PA lateral', from the septal mitral annulus, called 'PA septal', and from the right ventricle tricuspid annulus, called 'PA tricuspid'. Atrial EMD was defined as the time interval from the onset of atrial electrical activity (P wave on surface ECG) to the beginning of mechanical atrial contraction (late diastolic A wave). All three groups were compared with each other, and correlation analysis was performed to investigate the relationship between the PASI score and interatrial EMD.

RESULTS

PA lateral was significantly higher in both the mild-moderate psoriasis group and the severe psoriasis group compared to controls (69 ± 12 and 78 ± 13 vs. 60 ± 6 ms; p = 0.001). Also, PA septal (63 ± 11 vs. 53 ± 6 ms; p = 0.005, post hoc analysis) and PA tricuspid (49 ± 7 vs. 41 ± 5 ms; p = 0.009, post hoc analysis) were significantly higher in the severe psoriasis group than in the control group. Correlation analysis revealed that the PASI score was well correlated with PA lateral (r = 0.520, p < 0.001), PA septum (r = 0.460, p = 0.002), interatrial EMD (r = 0.371, p = 0.014) and intra-atrial EMD (r = 0.393, p = 0.009).

CONCLUSION

Atrial EMD was prolonged in patients with psoriasis. The measurement of atrial EMD might be used to determine the risk of development of AF in patients with psoriasis.

The relationship between atrial electromechanical delay and left atrial mechanical function in stroke patients

OBJECTIVE

The aim of this study was to evaluate the relationship between atrial electromechanical delay (EMD) measured with tissue Doppler imaging (TDI) and left atrial (LA) mechanical functions in patients with ischemic stroke and compare them with healthy controls.

METHODS

Thirty patients with ischemic stroke were enrolled into this cross-sectional, observational study. The control group consisted of 35 age- and gender-matched apparently healthy individuals patients. Acute cerebral infarcts of probable embolic origin were diagnosed via imaging and were confirmed by a neurologist. Echocardiographically, time intervals from the beginning of P wave to beginning of A wave from the lateral and septal mitral and right ventricular tricuspid annuli in TDI were recorded. The differences between these intervals gave the mechanical delays (inter- and intra-atrial). Left atrial (LA) volumes were measured using the biplane area-length method, and LA mechanical function parameters were calculated. Statistical analysis was performed using student's t-test, chi-squared test, and Pearson's test.

RESULTS

The laboratory and clinical characteristics were similar in the two groups. Increased left atrial EMD (21.36±10.38 ms versus 11.74±6.06 ms, p<0.001), right atrial EMD (13.66±8.62 ms versus 9.66±6.81 ms, p=0.040), and interatrial EMD (35.03±9.95 ms versus 21.40±8.47 ms, p<0.001) were observed in stroke patients as compared to controls. Active LA emptying volume and fraction and passive LA emptying volumes and fraction were similar between controls and stroke patients. Total LA emptying volumes were significantly increased in stroke patients as compared to healthy controls (33.19±11.99 mL/m2 versus 27.48±7.08 mL/m2, p=0.021).

CONCLUSION

According to the results of our study, interatrial electromechanical delay may be a new predictor for ischemic stroke.

Atrial electromechanical conduction delay in patients with neurocardiogenic syncope

AIM

We aimed to investigate the presence of atrial electromechanical conduction delay in patients with neurocardiogenic syncope, which was diagnosed with head-up tilt table test (HUTT).

MATERIALS AND METHODS

A total of 29 patients (mean age: 30.6 ± 15.9 years) with vasovagal syncope, as diagnosed by HUTT, and 23 healthy control subjects (mean age: 34.7 ± 16.3 years) with a negative HUTT were enrolled to the study. Atrial electromechanical conduction delay was defined as the time elapsed from the beginning of the P wave in the electrogardiogram to the beginning of the Am wave in tissue Doppler.

RESULTS

There was no statistically significant difference between the groups in terms of interatrial conduction delay, whereas the difference was significant with regard to the right intraatrial electromechanical conduction delay (P < 0.01) and the left intraatrial electromechanical conduction delay (P < 0.0001). There was a negative correlation between the left intraatrial electromechanical conduction delay and the right intraatrial electromechanical conduction delay (r = -0.486, P = 0.001), whereas a positive correlation was present with the interatrial electromechanical conduction delay (r = 0.507, P = 0.001).

CONCLUSION

In this study, the tissue Doppler method revealed that there is left and right intraatrial electromechanical conduction delay in patients with vasovagal syncope. The impact and role of atrial conduction delay as a pathophysiological determinant should be confirmed in further studies.

Evaluation of atrial electromechanical delay and diastolic functions in patients with hyperthyroidism

AIM

Hyperthyroidism is a well-known cause of atrial fibrillation (AF) which is associated with increased morbidity and mortality. Atrial electromechanical delay (EMD) is a significant predictor of AF. The aim of this study was to assess the atrial EMD and diastolic functions in subclinical and overt hyperthyroidism by using tissue Doppler imaging (TDI).

METHODS AND RESULTS

The study population consisted of 3 groups: group I (30 healthy subjects), group II (38 patients with subclinical hyperthyroidism), and group III (25 patients with overt hyperthyroidism). Atrial electromechanical coupling was measured with TDI. Standard echocardiographic measurements and parameters of diastolic function were obtained by conventional echocardiography and TDI. Intra- and inter-atrial EMD were significantly prolonged in subclinical and overt hyperthyroidism compared with control group (P = 0.03 and P < 0.001 for intra-atrial EMD; P < 0.001 for inter-atrial EMD). In groups II and III, mitral A velocity (P = 0.005 and P = 0.001) and mitral E-wave deceleration time (P < 0.001 and P = 0.02) were significantly increased, and mitral E/A ratio (P = 0.005 and P = 0.001) was significantly decreased compared with the control group. The lateral mitral Em /Am ratio in group II and group III was significantly lower than controls (P = 0.001). Mitral Em /Am ratio (β = -0.32, P = 0.002) and thyroid stimulating hormone (TSH) level (β = -0.27, P = 0.009) were negatively and independently correlated with inter-atrial EMD.

CONCLUSION

This study showed that intra- and inter-atrial electromechanical intervals were prolonged and diastolic function was impaired in both overt and subclinical hyperthyroidism. TSH level and mitral Em /Am ratio were found as independent predictors of atrial EMD.

Finding the "PR-fect" solution: what is the best tool to measure fetal cardiac PR intervals for the detection and possible treatment of early conduction disease?

In the absence of structural heart disease, the great majority of cases with complete congenital heart block will be associated with the maternal autoantibodies directed to components of the SSA/Ro-SSB/La ribonucleoprotein complex. Usually presenting in fetal life before 26 weeks' gestation, once third-degree (complete) heart block develops, it is irreversible. Therefore, investigators over the past several years have attempted to predict which fetuses will be at risk for advanced conduction abnormalities by identifying a biomarker for less severe or incomplete disease, in this case, PR interval prolongation or first-degree atrioventricular block. In this state-of-the-art review, we critically analyze the various approaches to defining PR interval prolongation in the fetus, and then analyze several clinical trials that have attempted to address the question of whether complete heart block can be predicted and/or prevented. We find that, first and foremost, definitions of first-degree atrioventricular block vary but that the techniques themselves are all similarly valid and reliable. Nevertheless, the task of predicting those fetuses at risk, and who are therefore candidates for treatment, remains challenging. Of concern, despite anecdotal evidence, there is currently no conclusive proof that a prolonged PR interval predicts complete heart block.

Tissue Doppler atrial conduction times and electrocardiogram interlead P-wave durations with varying severity of obstructive sleep apnea

OBJECTIVES

Obstructive sleep apnea (OSA) has been reported to be associated with an increased risk of atrial fibrillation. The aim of this study was to investigate atrial electromechanical couplings in patients with OSA and the relationship between these parameters and P-wave dispersion (Pd).

METHODS

One hundred twenty-six patients were enrolled in this study. All patients underwent polysomnographic examination. The apnea-hypopnea index (AHI) was defined as the number of apneas and hypopneas per hour of sleep. An AHI score of 5 or more was diagnosed as OSA, and an AHI score of less than 5 was diagnosed as OSA (-). Thirty-nine of the patients had an AHI score of less than 5 (group 1), 42 of the patients had AHI score between 5 and 30 (mild and moderate, group 2), 45 of the patients had an AHI score more than 30 (severe, group 3). Atrial electromechanical coupling (PA), intra-atrial, and interatrial electromechanical delay were measured with tissue Doppler imaging. P-wave dispersion was calculated from 12-lead electrocardiogram.

RESULTS

Maximum P-wave duration was higher in group 3 compared with groups 2 and 1 (126.0 ± 16.7 vs 111.0 ± 12.5 [P < .001] and 126.0 ± 16.7 vs 99.9 ± 10.0 [P < .001], respectively). Maximum P-wave duration was higher in group 2 than in group 1 (111.0 ± 12.5 vs 99.9 ± 10.0, P < .001). P-wave dispersion was higher in group 3 compared with groups 2 and 1 (50.9 ± 11.5 vs 37.0 ± 8.6 [P < .001] and 50.9 ± 11.5 vs 27.9 ± 6.8 [P < .001], respectively). P-wave dispersion was higher in group 2 than in group 1 (37.0 ± 8.6 vs 27.9 ± 6.8, P < .001). Minimum P-wave duration did not differ between the groups. Atrial PA at the left lateral mitral annulus (lateral PA), septal mitral annulus (septal PA), and right ventricular tricuspid annulus (RV PA) were significantly higher in group 3 than in group 2 (P < .001, P = .001, and P = .009, respectively). Lateral PA, septal PA, and RV PA were higher in group 2 compared with group 1 (P < .001, P = .003, and P = .009, respectively). Interatrial electromechanical delay (lateral PA - RV PA) was significantly longer in group 3 compared with groups 2 and 1 (33.6 ± 12.1 vs 22.4 ± 9.4 [P < .001] and 33.6 ± 12.1 vs 14.9 ± 9.2 [P < .001], respectively). Interatrial electromechanical delay was longer in group 2 than in group 1 (22.4 ± 9.4 vs 14.9 ± 9.2, P = .001). There was a positive correlation between AHI and Pd, lateral PA, septal PA, RV PA, interatrial electromechanical delay, and left-sided intra-atrial electromechanical delay.

CONCLUSION

Prolongation of electromechanical delay and increased Pd are associated with apnea-hypopnea index (AHI) and hence the severity of disease.

Diagnosing foetal atrioventricular heart blocks

Foetal echocardiographic ultrasound techniques still remain the dominating modality for diagnosing foetal atrioventricular block (AVB). Foetal electrocardiography might become a valuable tool to measure time intervals, but magnetocardiography is unlikely to get a place in clinical practice. Assuming that AVB is a gradually progressing and preventable disease, starting during a critical period in mid-gestation with a less abnormal atrioventricular conduction before progressing to a complete irreversible AVB (CAVB), echocardiographic methods to detect first-degree AVB have been developed. The time intervals obtained with these techniques are all based on the identification of mechanical or hemodynamic events as markers of atrial (A) and ventricular (V) depolarizations and will accordingly include both electrical and mechanical components. Prospective observational studies have demonstrated a transient prolongation of AV time intervals in anti-Ro/SSA antibody-exposed foetuses, but it has not succeeded to identify a degree of AV time prolongation predicting irreversible cardiac damage and progression to CAVB. Causes of sustained bradycardia include CAVB, 2:1 AVB, sinus bradycardia and blocked atrial bigeminy (BAB). Using foetal echocardiographic techniques and a systematic approach, a correct diagnosis can be made in almost every case. Sinus bradycardia and CAVB are usually easy to diagnose, but BAB has a tendency to be sustained and shows a high degree of resemblance with 2:1 AVB when diagnosed during mid-gestational. As BAB resolves without treatment and 2:1 AVB may respond to treatment with fluorinated steroids, a correct diagnosis becomes an issue of major importance to avoid unnecessary treatment of harmless and spontaneously reversing conditions.

Relation of gender and interatrial dyssynchrony on tissue Doppler imaging to the prediction of the progression to chronic atrial fibrillation in patients with nonvalvular paroxysmal atrial fibrillation

This prospective study aimed to identify the relation of gender and interatrial dyssynchrony on tissue Doppler imaging (TDI) to the prediction of the progression to chronic atrial fibrillation (CAF) in nonvalvular paroxysmal AF (PAF) patients. Nineteen consecutive men and 19 women with nonvalvular PAF were prospectively followed after echocardiography. We measured the interval of time from initiation of the P wave on the electrocardiogram until the beginning of the late diastolic TDI signal at the lateral border of the mitral (P-A'(M)) and the tricuspid annulus (P-A'(T)). Interatrial dyssynchrony was defined as the difference between the P-A'(M) and P-A'(T) intervals (A'(M)-A'(T)). The study endpoint was the onset of CAF (>6 months). Six men developed CAF during a follow-up of 32 +/- 26 months, and 3 women developed CAF during a follow-up of 25 +/- 19 months. Compared to those without CAF, the patients with CAF had significantly longer A'(M)- A'(T) intervals (men: 41 +/- 10 vs 27 +/- 12 ms, women: 64 +/- 4 vs 23 +/- 9 ms; P < 0.01) in both genders. Kaplan-Meier analysis, using cutoff values determined by analysis of receiver-operating characteristics curves, revealed that the progression to CAF was significantly observed more often when A'(M)-A'(T) interval was >34 ms in men and >43 ms in women. This prospective study suggests that nonvalvular PAF men and women with a high risk of developing CAF have "interatrial dyssynchrony" on atrial TDI, whose cutoff values are shorter and may affect the vulnerability of AF in men.

Atrial function during different multisite atrial pacing modalities in patients with bradycardia--tachycardia syndrome

BACKGROUND

Multisite atrial pacing (MAP) was introduced to improve atrial electrical synchrony and prevent recurrence of atrial fibrillation (AF).

METHODS AND RESULTS

In the present study there were 57 patients with sinus node disease, AF recurrence and prolonged P-wave on ECG with 2 MAP modalities. In all patients 1 lead was implanted in the coronary sinus (CS) ostium area. In the right atrial appendage (RAA)+CS group (28 patients) the other atrial lead was in the RAA, and in the BB+CS group (29 patients) in the Bachmann's bundle (BB) region. Tissue Doppler was used to register the electromechanical delay (EMD) in the atrial walls and estimate the atrial contraction synchrony. Cardiac output and myocardial performance index did not differ during the 2 MAP modalities. During BB+CS, in comparison with RAA+CS pacing, the peak of the mitral atrial wave occurred earlier (P<0.01), the usual right-left atrial contraction sequence was reversed more frequently (P<0.004), all atrial EMDs except for the lateral left atrium (LA) were shorter (P<0.05), and LA synchrony was greater (P<0.001).

CONCLUSIONS

In patients treated with MAP, implanting 1 of the atrial leads in the BB area instead of the RAA has no influence on global cardiac hemodynamics, but does result in earlier LA contraction, and reversal of the typical right-left atrial contraction sequence, as well as providing greater LA contraction synchrony.

Early Diagnosis and Treatment of Atrioventricular Block in the Fetus Exposed to Maternal Anti-SSA/Ro-SSB/La Antibodies

Background— A fetus exposed to maternal anti-SSA/Ro or anti-SSB/La antibodies (or both) may develop complete atrioventricular block (AVB), which results in high prenatal and postnatal morbidity and mortality. Until recently, only high-grade AVB could be diagnosed in utero. The tissue velocity–based fetal kinetocardiogram (FKCG) enables accurate measurement of AV conduction time and diagnosis of low-grade AVB. In the present multicenter observational study, we used FKCG to detect first-degree AVB in fetuses at risk.

Methods and Results— FKCG was performed in 70 fetuses of 56 mothers who were positive for anti-SSA/Ro and/or anti-SSB/La. Fetuses were monitored with weekly FKCG from 13 to 24 weeks’ gestation, followed by monthly assessments until delivery in unaffected fetuses and weekly assessments in affected fetuses. AV conduction in 70 at-risk and 109 normal fetuses was compared. FKCG was obtained readily in all fetuses; 6 showed first-degree AVB (AV conduction time >2 z scores above normal mean) at 21 to 34 gestational weeks. Immediate maternal treatment with dexamethasone resulted in normalization of AV conduction in all affected fetuses within 3 to 14 days. AV conduction time in the remaining 64 untreated fetuses remained normal throughout gestation. The ECG PR interval immediately after birth was normal in all affected newborns. No child developed AVB or cardiomyopathy in the subsequent 1- to 6-year (median 4-year) follow-up.

Conclusions— The present findings suggest that an FKCG can detect first-degree AVB in the fetus exposed to maternal anti-SSA/Ro or anti-SSB/La antibodies (or both). Dexamethasone given on detection was associated with normalized AV conduction in fetuses with first-degree AVB. No fetus in the present study developed complete prenatal or postnatal AVB.

Interatrial conduction time and left atrial function in patients with left ventricular systolic dysfunction: effects of cardiac resynchronization therapy

BACKGROUND

Prolonged interatrial conduction time (IACT) can be associated with abnormal left atrial (LA) function but has not been characterized in patients with left ventricular (LV) systolic dysfunction (LVSD) and QRS intervals >130 ms.

METHODS

Two-dimensional Doppler echocardiography and Doppler tissue imaging (DTI) were performed in 41 patients with LVSD (mean LV ejection fraction, 26 +/- 5%) and 41 similarly aged normal controls. Two-dimensional measurements included LV volume and ejection fraction and LA volume for the determination of LA emptying fraction and LA ejection fraction. IACT was defined as the time from the onset of the P wave to the onset of the DTI-derived late diastolic (A') velocity at the lateral mitral annulus. Two-dimensional Doppler measurements were reassessed in patients with LVSD 4 +/- 2 months after cardiac resynchronization therapy (CRT).

RESULTS

IACT was longer in patients with compared to controls (105 +/- 25 vs 74 +/- 12 ms, P < .001); none of the controls had an IACT > 100 ms. In patients with LVSD, IACT was correlated modestly with measurements of LA volume (r = .41-.48, all P values < .009) but not with measurements of LA function. Patients with LVSD with IACTs > 100 ms (n = 20) prior to CRT had larger LA volumes and lower indices of LA function after CRT compared to those with IACTs < or = 100 ms. Significant reductions in LV end-systolic volumes and increases in LV ejection fractions occurred in both groups after CRT.

CONCLUSION

DTI-derived IACT can be prolonged in patients with severe LVSD and wide QRS intervals. An IACT > 100 ms can affect LA remodeling and function at early follow-up after CRT but does not influence the response in LV end-systolic volume or ejection fraction.

Assessment of atrial electromechanical coupling and influential factors in nonrheumatic paroxysmal atrial fibrillation

BACKGROUND

Sequential analysis of atrial electromechanical coupling (P-A) by Doppler tissue imaging (DTI) might provide important insight into the mechanisms of paroxysmal atrial fibrillation (PAF).

HYPOTHESIS

The purpose of this study was to evaluate P-A and the dispersion of P-A, and to analyze the influential factors of P-A.

METHODS

One hundred and ten patients with PAF and 87 normal controls were enrolled. Using DTI, the time intervals from the beginning of P-wave to the onset of atrioventricular ring motion related to atrial contraction were measured.

RESULTS

Atrial electromechanical coupling at the interventricular septum atrioventricular annulus (P-A1), left lateral mitral annulus (P-A2) and right lateral tricuspid annulus (P-A3) in PAF group were significantly longer than those in control (p < 0.001). The difference between P-A2 and P-A1 (T1), P-A2 and P-A3 (T3) in PAF group were greater than those in control before age correction (p < 0.05). The linear regression analysis showed that the duration of PAF episodes and age were the greatest influential factors of P-A1 (r = 0.564). Left atrial anterior-posterior dimension (LAD) and age were the greatest influential factors of P-A2 (r = 0.459). The LAD was the greatest influential factors of T1 and T3 (r = 0.408, 0.542).

CONCLUSIONS

The atrial electromechanical coupling was significantly longer and the dispersion of P-A at left lateral mitral annulus was greater in PAF patients. The prolongation of P-A may be related to left atrial enlargement, long episodes of PAF and aging and the dispersion of P-A at left lateral mitral annulus to LAD.

Strain Rate Imaging for Noninvasive Functional Quantification of the Left Atrium in Hypertensive Patients with Paroxysmal Atrial Fibrillation

AIM

Strain rate (SR) imaging has been applied to the detection of regional left ventricular (LV) dysfunction but not as much to the assessment of left atrial (LA) function. We aimed to assess atrial myocardial properties during atrial fibrillation (AF) by myocardial velocity, SR and strain, focusing on the effects of hypertension and atrial arrhythmias, especially paroxysmal AF.

METHODS

We compared 3 groups of a total of 110 consecutive patients with hypertension presenting to our institution: 20 with brief atrial tachycardia, 20 with paroxysmal AF and 70 with hypertension alone. These patients and 32 controls underwent transthoracic echocardiography, tissue velocity imaging (TVI), strain examination and SR imaging. Atrial tissue velocity, strain and SR values of hypertensive patients were compared with those of age-matched controls.

RESULTS

Compared with controls, hypertensive patients with paroxysmal AF showed significantly increased atrial myocardial features as assessed by TVI (p < 0.05-0.001). Time to peak late diastolic SR corrected for heart rate (TASRc) and the difference of early diastolic SR (deltaESR) were significantly increased (both p < 0.05), whereas the difference of late diastolic SR (deltaASR) (p < 0.05) and the difference of TASRc (deltaTASRc) (p < 0.001) were significantly decreased; moreover, systolic SR (SSR), deltaASR and deltaTASRc were significantly decreased (p < 0.05, p < 0.01 and p < 0.001, respectively), whereas deltaESR was significantly increased (p < 0.01), as compared with hypertensive patients without arrhythmia. No other parameters differed among the 4 groups.

CONCLUSIONS

SR imaging combined with TVI enables noninvasive quantification of LA dysfunction due to hypertension and paroxysmal AF. In hypertensive patients, paroxysmal AF decreases the efficiency, not the ability, of LA myocardia to reserve potential energy, which suggests that LA myocardial reservoir function decreases. The impaired conductivity of the left atrium leads to decreased total active atrial contraction and prolonged interatrial conduction. Thus, the temporal asynchrony of the atria is enhanced, but contraction asynchrony is reduced.

PR interval: a comparison of electrical and mechanical methods in the fetus

BACKGROUND

Mechanical surrogates are used to assess fetal cardiac electrical activity.

AIMS

To compare electrical PR interval measured using non-invasive fetal electrocardiography (fECG) with mechanical atrioventricular (AV) interval using Doppler.

STUDY DESIGN AND SUBJECTS

Prospective study of 55 recordings made in 50 human fetuses. Those with structural heart defects, second degree or complete heart block were excluded.

OUTCOME MEASURES

Mechanical AV interval was measured from the onset of mitral A wave to onset of aortic ejection. Electrical PR interval was measured from a coherent averaged signal obtained using non-invasive fECG recorded from the maternal abdomen. Wilcoxon signed rank test was used to compare both methods. Agreement between AV and PR intervals was assessed using linear regression and by Bland-Altman plots. Bland-Altman analysis assessed inter-observer and intra-observer variability.

RESULTS

There was no significant difference in the heart rates of the 55 paired traces measured consecutively using both methods (p<0.35). AV interval was longer than PR (median [range] 116 [96-169] vs. 102 [75-143] ms; p<0.001), with mean difference -16.47 ms (95% Confidence Interval -43.43, 10.44), reflecting the increased proportion of the cardiac cycle measured. Using fECG, PR inter-observer and intra-observer mean differences were 0.4 ms (CI -7.29, 8.09) and 0.7 ms (CI -3.22, 4.62) respectively. R values for inter and intra-observer studies were 0.95 and 0.99 respectively. Using Doppler methods, AV inter-observer and intra-observer mean differences were -2.69 ms, (CI -15.33, 9.95) and 0.92 ms, (CI -9.41, 11.26) respectively. R values for AV measurements were 0.93 for inter-observer and 0.96 for intra-observer variation.

CONCLUSIONS

Non-invasive fECG is a robust tool to measure the PR interval with narrow limits of agreement.

Assessment of Atrial Conduction in Patients with Scleroderma by Tissue Doppler Echocardiography and P Wave Dispersion

BACKGROUND

Atrial conduction abnormalities in patients with scleroderma have not been evaluated in terms of P wave duration, P wave dispersion (P(d)) and electromechanical coupling measured by tissue Doppler echocardiography.

METHODS

Twenty-four patients with scleroderma and 24 control subjects underwent resting electrocardiogram (ECG), M mode and tissue Doppler echocardiography. The P wave duration was calculated in all leads of the surface ECG. The difference between the maximum (P(max)) and minimum P wave duration was calculated and defined as P(d). Interatrial and intraatrial electromechanical delays were measured with tissue Doppler tissue echocardiography.

RESULTS

The left ventricular dimensions, fractional shortening, and left atrial diameter did not differ between the patients and the controls. P(d) and P(max) were significantly higher in patients with scleroderma compared with controls: 51 +/- 17 versus 28 +/- 7 ms (p < 0.01) and 109 +/- 10 versus 93 +/- 6 ms (p < 0.01), respectively. There was a delay between the onset of the P wave on surface ECG and the onset of the late diastolic wave (A wave; PA) obtained by tissue Doppler echocardiography in patients with scleroderma compared with controls measured at lateral septal annulus (lateral PA; 122 +/- 8 vs. 105 +/- 7 ms, p = 0.001), septal mitral annulus (104 +/- 11 vs. 93 +/- 10 ms, p = 0.01) and tricuspid annulus (right ventricular PA; 71 +/- 9 vs. 64 +/- 7 ms, p = 0.05). Interatrial conduction time (lateral PA - right ventricular PA) was delayed in patients with scleroderma compared with controls (88 +/- 13 vs. 76 +/- 11 ms, p = 0.01). A positive correlation was detected between interatrial electromechanical delay (lateral PA - right ventricular PA) and P(d) (r = 0.5, p = 0.03).

CONCLUSION

Atrial conduction abnormalities as estimated with P(d) and P(max) are significantly higher in patients with scleroderma compared with controls. There is a delay in both intraatrial and interatrial electromechanical coupling intervals in patients with scleroderma.

Assessment of fetal atrioventricular time intervals by tissue Doppler and pulse Doppler echocardiography: normal values and correlation with fetal electrocardiography

OBJECTIVE

To establish gestational age-specific reference values of normal fetal atrioventricular (AV) time interval by spectral tissue Doppler imaging (TDI) and pulse-wave Doppler (PD) methods, and to assess their correlation with signal-averaged fetal PR intervals (ECG).

DESIGN

Cohort study.

SETTING

Tertiary centre for fetal cardiology. PATIENTS AND MEASURES: 131 pregnant women between 14 and 42 weeks' gestation underwent 196 fetal echocardiograms and 158 fetal ECG studies. TDI-derived AV intervals were measured as the intervals from atrial contraction (Aa) to isovolumic contraction (IV) and from Aa to ventricular systole (Sa) at the right ventricular free wall. PD-derived AV intervals were measured from simultaneous left ventricular inflow/outflow (in/out) and superior vena cava/aorta (V/AO) recordings.

RESULTS

Measurements were possible by ECG in 61%, by TDI in 100%, by in/out in 100% and by V/AO in 97% of examinations. Aa-IV correlated significantly better with PR intervals (y = 0.67x + 38.29, R(2) = 0.15, p < 0.0001, mean bias 8.0 ms) than did in/out (R(2) = 0.10, p = 0.002, bias 18.7 ms) and V/AO (R(2) = 0.06, p = 0.02, bias 12.4 ms). Gestational age and AV intervals were positively correlated with all imaging modalities (R(2) = 0.19-0.31, p < 0.0001).

CONCLUSION

This study showed the feasibility of fetal AV interval measurements by TDI, and established gestational age-specific reference data. TDI-derived Aa-IV intervals track ECG PR intervals more closely than PD-derived AV intervals and thus should be used as the ultrasound method of choice in assessing fetal AV conduction.

Doppler tissue imaging in the assessment of atrioventricular conduction time: validation of a novel technique and comparison with electrophysiologic and pulsed wave Doppler-derived equivalents in an animal model

Accurate assessment of atrioventricular conduction time (AVCT) is crucial for early detection of evolving fetal heart block. Simultaneous pulsed wave Doppler (PD) interrogation of left ventricular inflow and outflow is mainly used to study fetal AVCT. Limitations of this modality include its dependency on loading conditions and merging early and late diastolic inflow waves at faster heart rate (HR). Sequential analysis of atrioventricular myocardial motion by Doppler tissue imaging (DTI) might be more useful in this regard. In 15 open-chest pigs, AVCT was measured by PD, DTI, and electrocardiogram at baseline HR and during incremental atrial pacing up to 200 beats/min. Electromechanical delay and pre-ejection period were assessed at baseline and maximal HR. DTI-derived AVCT correlated better with PR intervals and allowed measurements at faster HRs than did PD (P < .05). Pre-ejection period prolonged with faster HR (P < .001), unlike electromechanical delay. In conclusion, DTI allows more accurate measurement of AVCT over a wider HR range than does PD.

Effect of Age and Heart Rate on Atrial Mechanical Function Assessed by Doppler Tissue Imaging in Healthy Individuals

BACKGROUND

The potential usefulness of Doppler tissue imaging (DTI) to assess atrial mechanical function in cardiac disease has been demonstrated. However, there are few reports on normal values of atrial function by DTI analysis.

METHODS

Echocardiography with color-coded DTI was performed in 131 healthy control subjects. The peak atrial contraction velocity (V(A)) and the timing of mechanical events were assessed offline at the left atrial (LA) and right atrial (RA) free wall and interatrial septum.

RESULTS

V(A) was higher in the RA (9.0 +/- 2.6 cm/s) than the LA (7.5 +/- 2.4 cm/s, P < .001), and both sites were higher than the interatrial septum (5.6 +/- 1.3 cm/s, both P < .001). The interatrial delay was 24 +/- 21 milliseconds. V(A) at the LA was higher in the participants aged 60 years or older than those who were younger than 60 years (8.1 +/- 2.7 vs 6.7 +/- 1.4 cm/s, P < .001), as was the velocity at the RA (9.6 +/- 2.8 vs 8.0 +/- 2.1 cm/s, P < .01). V(A) at the LA was higher in the participants with heart rate of 60/min or higher than those with lower heart rate (7.9 +/- 2.5 vs 6.8 +/- 1.8 cm/s, P < .05). Sex difference had no effect on V(A) and timings of atrial events.

CONCLUSIONS

Assessment of atrial mechanical function by DTI is feasible in healthy individuals. The V(A) is the highest at the RA, followed by LA, and the lowest at the interatrial septum. Older age and faster heart rate seems to augment V(A) in the atrial walls.

Doppler Tissue Evaluation of Intra-atrial and Interatrial Electromechanical Delay and Comparison with P-wave Dispersion in Patients with Mitral Stenosis

OBJECTIVE

The aim of our study was to: (1) measure atrial electromechanical delay in patients with mitral stenosis (MS) and in a control group; (2) find the echocardiographic parameters that affect atrial electromechanical delay; and (3) examine the correlation between atrial electromechanical delay and P-wave dispersion (PWD).

METHODS

A total of 25 patients with pure MS (age 43 +/- 10 years; 18 women, 7 men) and 16 control subjects (age 41 +/- 8 years; 9 women, 7 men) were studied. Interatrial and intra-atrial electromechanical delay was measured with Doppler tissue echocardiography. From the 12-lead electrocardiograms, PWD was calculated.

RESULTS

Interatrial electromechanical delay was 71.2 +/- 33 in the MS group and 40.5 +/- 21.0 in the control group (P = .01). In the MS group, PWD was 50 +/- 7 and in the control group it was 29 +/- 5 (P = .03). A positive correlation was detected between interatrial electromechanical delay and PWD (r = 0.6, P = .03).

CONCLUSION

This study shows that interatrial electromechanical delay gets longer in MS and is correlated with PWD. Atrial electromechanical delay is related with left atrial size but not with severity of MS.