Left ventricular (LV) dysfunction is 1 of the major determinants of late adverse clinical
outcomes in patients after surgical repair of tetralogy of Fallot (TOF). The aim of
this study was to test the hypothesis that LV myocardial deformation is impaired in
patients after TOF repair and related to right ventricular (RV) dilation and exercise
capacity. Longitudinal, radial, and circumferential LV myocardial deformation was
determined using speckle-tracking echocardiography in 23 postoperative patients with
TOF and compared to that of 23 age-matched controls. Relations between LV strain and
strain rate (SR) and RV volumes and exercise parameters were determined in patients.
Compared to controls, patients had reduced global LV longitudinal, radial, and circumferential
strain (all p values <0.05). Patients with significantly increased RV end-systolic
volume (>2 SDs higher than normal; n = 17) had reduced global LV circumferential strain
(p = 0.048) and SR (p = 0.038), but similar longitudinal and radial speckle-tracking
echocardiographic parameters, compared to those without (n = 6). RV end-systolic volume
was correlated inversely with global LV circumferential strain and SR (r = -0.58,
p = 0.004, and r = -0.58, p = 0.005, respectively), while RV end-diastolic volume
was correlated only with global LV circumferential strain (r = -0.43, p = 0.047).
In patients, the LV ejection fraction was correlated with global LV circumferential
strain (r = 0.54, p = 0.01) and SR (r = 0.66, p = 0.001) but not with longitudinal
or radial speckle-tracking echocardiographic parameters. Using multivariate analysis,
global LV circumferential SR (beta = 0.66, p = 0.001) and male gender (beta = 0.46,
p = 0.012) were identified as independent predictors of peak oxygen consumption. In
conclusion, the negative impact of RV dilation on LV function relates to its influence
on LV circumferential strain and SR in patients after TOF repair.