Atrial involvement in patients with progressive systemic sclerosis: Relationship between ultrasonic tissue characterization of the atrium and interatrial conduction

Objective: The aim of this study was to assess atrial lesions using ultraso nic tissue characterization and to determine the contribution of atrial les ions to the interatrial electromechanical coupling conduction time in patie nts with progressive systemic sclerosis (PSS). Methods: Twenty patients wit h PSS and 20 age-matched healthy controls were evaluated. The cyclic variat ion in integrated backscatter value (CV-IB) was measured at the interatrial septum (IAS) from apical four chamber view. M-modes of ventricular long ax is motion along with phono- and electrocardiograms were recorded simultaneo usly at the right lateral (RT) and left lateral (LT) sites of the atriovent ricular (AV) rings and central fibrous body (CFB) in the apical four-chambe r view. Intervals from the P wave on ECG to the echocardiographic onset of atrial contraction as a point of inflection in long axis M-mode echocardiog ram were measured at the RT and LT sites of AV rings and CFB (P-RT, P-LT, P -SEP, respectively). Interatrial electromechanical coupling conduction time was determined as [(P-LT) - (P-RT)]. Results: In patients with PSS compare d to normal controls, P-RT, P-SEP, P-LT, and interatrial conduction time we re greater, while CV-IB in IAS decreased. Furthermore, CV-IB in IAS correla ted well with interatrial conduction time (r = 0.7, p < 0.01) in patients w ith PSS. Conclusions: Interatrial electromechanical coupling times may be p rolonged due to atrial tissue damage in patients with PSS.