Abstract

Background: The total atrial conduction time (TACT) is an independent predictor of atrial fibrillation (AF). A new transthoracic echocardiographic tool to determine TACT by tissue Doppler imaging (PA-TDI (the time from the initiation of the P wave on the ECG (lead II) to the A′ wave on the lateral left atrial tissue Doppler tracing)) has been developed recently.

Objective: To test the hypothesis that measurement of PA-TDI enables prediction of new-onset AF.

Methods: 249 Patients without a history of AF were studied. All patients underwent an echocardiogram and the PA-TDI interval was measured. Patient characteristics and rhythm at follow-up were recorded.

Results: During a mean (SD) follow-up of 680 (290) days, 15 patients (6%) developed new-onset AF. These patients had a longer PA-TDI interval than patients who remained in sinus rhythm (172 (25) ms vs 150 (20) ms, p = 0.001). Furthermore, the patients developing AF were older, more often had a history of heart failure or chronic obstructive pulmonary disease, more often used α blockers, had enlarged left atria and more frequently mitral incompetence on the echocardiogram. After adjusting for potential confounders, Cox regression showed that PA-TDI was independently associated with new-onset AF (OR = 1.375; 95% CI 1.037 to 1.823; p = 0.027). The 2-year incidence of AF was 33% in patients with a PA-TDI interval >190 ms versus 0% in patients with a PA-TDI interval <130 ms (p = 0.002).

Conclusions: A prolonged PA-TDI interval may predict the development of new-onset AF. This measure may be used to identify patients at risk in future strategies to prevent the development or complications of AF.