Assessment of left atrial electro-mechanical delay to predict atrial fibrillation in hypertrophic cardiomyopathy

AIMS

Atrial fibrillation (AF) is frequently observed in hypertrophic cardiomyopathy (HCM) and is associated with poor clinical outcome. Total atrial conduction time, estimated by tissue Doppler imaging (TDI), the so-called PA-TDI duration, reflects the left atrial (LA) structural and electrical remodelling. The aim of this study was to evaluate the association between PA-TDI and new-onset AF in patients with HCM.

METHODS AND RESULTS

From a large cohort of patients with HCM, 208 patients (64% male, mean age 53 ± 14 years) without AF were selected. PA-TDI duration was measured from the onset P wave on electrocardiogram to the peak A' wave of the lateral LA wall using TDI. The incidence of new-onset AF was 20% over a median follow-up of 7.3 (3.5-10.5) years. Patients with incident AF had longer PA-TDI duration when compared with patients without AF (133.7 ± 23.0 vs. 110.5 ± 30.0 ms, P < 0.001). PA-TDI duration was independently associated with new-onset AF (hazard ratio: 1.03, 95% confidence interval: 1.01-1.05, P < 0.001).

CONCLUSION

Prolonged PA-TDI duration was independently associated with new-onset AF in patients with HCM. This novel parameter could be useful to risk-stratify patients with HCM who are at risk of having AF.

Assessment of atrial functional remodeling in patients with atrioventricular nodal reentrant tachycardia with and without drug-induced type 1 Brugada pattern: A case-control study

PURPOSE

The time interval between the onset of the P-wave on electrocardiogram (ECG) and peak A' velocity of the lateral left atrial wall assessed by tissue Doppler imaging (PA-TDI interval) determine total atrial conduction time (TACT) which reflects atrial remodeling and arrhythmic substrate. In this retrospective study, we aimed to assess TACT in patients with atrioventricular nodal reentrant tachycardia (AVNRT) with and without drug-induced type 1 Brugada electrocardiogram ECG pattern (DI-Type 1 BrP) and control subjects.

METHODS

Study population consisted of 62 consecutive patients (46 women; mean age 44 ± 12 years) undergoing electrophysiological study and ablation for symptomatic, drug-resistant AVNRT, and 42 age-matched and sex-matched control subjects. All patients and control subjects underwent ajmaline challenge test and tissue Doppler imaging.

RESULTS

A DI-Type 1 BrP was uncovered in 24 of 62 patients with AVNRT (38.7%). PA-TDI interval was similar among AVNRT patients with and without DI-Type 1 BrP (124 ± 12 ms vs 119 ± 14 ms, respectively, P = .32), but significantly longer in patients with AVNRT with as well as without DI-Type 1 BrP than in control subjects (124 ± 12 ms and 119 ± 14 ms vs 105 ± 11 ms, respectively, P < .001).

CONCLUSION

The TACT assessed by PA-TDI interval is longer in patients with AVNRT with and without DI-Type 1 BrP than in age-matched and sex-matched healthy control subjects.

Relationship of the total atrial conduction time to subclinical atherosclerosis, inflammation and echocardiographic parameters in patients with type 2 diabetes mellitus

OBJECTIVES

The aim of our study was to evaluate the total atrial conduction time and its relationship to subclinical atherosclerosis, inflammation and echocardiographic parameters in patients with type 2 diabetes mellitus.

METHODS

A total of 132 patients with type 2 diabetes mellitus (mean age 54.5 ± 9.6 years; 57.6% male) and 80 age- and gender-matched controls were evaluated. The total atrial conduction time was measured by tissue-Doppler imaging and the carotid intima-media thickness was measured by B-mode ultrasonography.

RESULTS

The total atrial conduction time was significantly longer in the patients with type 2 diabetes mellitus than in the control group (131.7 ± 23.6 vs. 113.1 ± 21.3, p<0.001). The patients with type 2 diabetes mellitus had significantly increased carotid intima-media thicknesses, neutrophil to lymphocyte ratios and high-sensitivity C-reactive protein levels than those of the controls. The total atrial conduction time was positively correlated with the high-sensitivity C-reactive protein level, neutrophil to lymphocyte ratio, carotid intima-media thickness and left atrial volume index and negatively correlated with the early diastolic velocity (Em), Em/late diastolic velocity (Am) ratio and global peak left atrial longitudinal strain. A multiple logistic regression analysis demonstrated that the neutrophil to lymphocyte ratio, carotid intima-media thickness and global peak left atrial longitudinal strain were independent predictors of the total atrial conduction time.

CONCLUSIONS

We suggest that subclinical atherosclerosis and inflammation may represent a mechanism related to prolonged total atrial conduction time and that prolonged total atrial conduction time and impaired left atrial myocardial deformation may be represent early subclinical cardiac involvement in patients with type 2 diabetes mellitus.

Left atrial appendage flow velocity and time from P-wave onset to tissue Doppler-derived A' predict atrial fibrillation recurrence after radiofrequency catheter ablation

BACKGROUND

Atrial fibrillation (AF) is associated with atrial remodeling. We investigate the abilities of preprocedural echocardiographic parameters reflecting atrial remodeling to predict AF recurrence after radiofrequency catheter ablation (RFCA) for paroxysmal AF (PAF).

METHODS

Preprocedural echocardiographic parameters were measured during sinus rhythm in 105 patients with PAF undergoing RFCA. Electrical remodeling was assessed by the time from the onset of the P-wave to the peak A'-wave on the tissue Doppler imaging (PA-TDI), functional remodeling was assessed by the left atrial appendage flow velocity (LAAFV), and structural remodeling was assessed by the left atrial volume index (LAVI). PA-TDI, LAAFV, and LAVI values were divided into tertiles, and their abilities to predict AF recurrence were assessed using Cox regression analysis.

RESULTS

AF recurrence occurred in 39/105 (37.1%) patients. After adjustment for confounders, the rate of AF recurrence was significantly higher in the highest tertile of PA-TDI compared with the lowest tertile (≥151.3 msec vs. <131.0 msec; hazard ratio [HR]: 2.477, 95% confidence interval [CI]: 1.031-5.950; P = 0.042), and in the lowest tertile of LAAFV compared with the highest tertile (<48.5 cm/sec vs. ≥64.9 cm/sec; HR: 2.680, 95% CI: 1.136-6.318; P = 0.024). The risk of AF recurrence was also higher in the highest tertile of LAVI (≥34.2 mL/m(2) ) compared with the lowest tertile, but this difference was not significant (HR: 2.146, 95% CI: 0.834-5.523; P = 0.113).

CONCLUSIONS

LAAFV (reflecting functional remodeling) and PA-TDI (reflecting electrical remodeling) are independent predictors of AF recurrence after RFCA for PAF.

Total atrial conduction time assessed by tissue doppler imaging (PA-TDI Interval) to predict early recurrence of persistent atrial fibrillation after successful electrical cardioversion

BACKGROUND

The aim of this study was to investigate whether total atrial conduction time (TACT) assessed via tissue Doppler imaging (PA-TDI interval) can identify patients with early recurrent atrial fibrillation (ERAF) after successful direct-current electrical cardioversion (CV) of persistent atrial fibrillation (persPAF).

METHODS AND RESULTS

A total of 54 patients without antiarrhythmic drug medication (mean ± SD: 66 ± 10.4 years; 33% women) with persPAF and successful CV were enrolled between May 2012 and May 2013. TACT was measured 6 hours after successful CV in the left atrium by tissue Doppler imaging (PA-TDI interval). ERAF was determined via Holter-electrocardiogram over a period of 7 days after CV. Receiver opearting characteristic analysis was used to determine an optimal cutoff value of PA-TDI interval for prognosis of ERAF. Based on this result, recurrence-free survival was assessed with Mantel-Haenszel's log-rank test. ERAF occurred in 23 patients (43%). PA-TDI interval was longer in patients with ERAF compared to those who maintained sinus rhythm (mean ± SD: 163.5 ± 11.1 vs 132.3 ± 11.2 milliseconds; P < 0.00001). At the cutoff value of 152 milliseconds, PA-TDI interval sensitivity and specificity related to ERAF were 87% and 100%, respectively.

CONCLUSION

Measuring PA-TDI interval may help to predict ERAF after successful CV in patients with persAF.