Objectives: The aim of this study was to evaluate the usefulness of transesophageal echocardiography (TEE) for the diagnosis of arrhythmogenic right ventricle cardiomyopathy (ARVC).
Patients: Using TEE and the standard transthoracic echocardiography (TTE), we studied 19 patients affected with hyperkinetic ventricular arrhythmias with a LBBB pattern, as well as 10 normal control subjects (C).
Methods: We calculated the following parameters: the fractional area change (FAC) of the end-diastolic right ventricule (RV) area; the global wall motion score (WMS) by the algebraic sum of the score of each of the 9 wall segments including the inflow, outflow and apex of RV; the asynergy index (AI) by the percentage of the 9 segments with a score > or = 2; the average thickness of moderator band and papillar muscles (ATMP); the echo reflectivity score (ERS) and the structural abnormalities score (SAS) of RV. The diagnosis of ARVC was proposed when RV segmental wall motion abnormalities were visualized, or when a decrease of the ventricular FAC and dysmorphic aspects were contemporaneously present. The results of the two echocardiographic approaches were compared, and in arrhythmic patients (A) echocardiographic results were compared with those obtained by cineventriculography (CVG), which we had adopted as the reference diagnostic method.
Results: The comparison between A and C showed significant differences for all parameters if calculated by the TEE (p < 0.003-0.0001), except for ATMP if calculated by TTE (p < 0.003-0.0001). The comparison between TEE and TTE approaches did not show any difference in the C group while in the A group only FAC and ERS resulted similar; the values of the remaining parameters were significantly greater if calculated by TEE than by TTE (WMS = 7.3 +/- 4.1 vs 4.3 +/- 2.3: p < 0.01; AI = 22.6 +/- 18.5 vs 11.6 +/- 10.3: p < 0.05; ATMP = 6.1 +/- 0.9 vs 5 +/- 1.2 mm: p < 0.04; SAS = 2.2 +/- 0.8 vs 1.4 +/- 0.7: p < 0.002). In 17 of the 19 patients who were clinically suspected to be affected with ARVC the diagnosis was confirmed by CVG; 12 of them (70%) were correctly identified by TTE and 17 (100%) by TEE. One of the two negative patients was erroneously considered positive both by TTE and TEE.
Conclusions: TEE is a usefull diagnostic tool for ARVC and is more accurate than TTE for the identification of the concealed or dubitative forms of the disease.