Integrated Ventricular Mechanics in “Healthy” Heart Transplant Patients

Although recently studies using Speckle Tracking Echocardiography (STE) on heart transplant (HTX) recipients have been published, an integrated assessment of myocardial properties is lacking. Thus our aim was to perform, by STE, an integrated study of ventricular mechanics in “healthy” HTX recipients. Standard echo-Doppler and STE study were performed in 50 HTX patients (age 50.4 ± 7.8, M/F = 37/13, follow-up 7.6 ± 5.3 years) without symptoms (NYHA I) and with preserved ejection fraction (EF) (HTX Group). As controls 35 age-, sexand BSA-matched normal subjects were studied (CTRL Group). Compared to CTRL group our HTX recipients showed: a) impaired left ventricular (LV) longitudinal, circumferential and radial Strain values (p<0.01) with a lesser degree of reduction at the apical segments; b) normal apical longitudinal, circumferential and radial Strain Rate values with reduction in the remaining segments; c) preservation of LV apical rotation and basal impairment (p<0.0001) with normal LV twist; d) delayed untwisting due to prolonged twist (p<0.0001) and thus prolongation of isovolumic relaxation time (p<0.01) in presence of normal E/E’ ratio; e) reduced right ventricular TAPSE, S’ (p<0.0001) and longitudinal Strain and SR (p<0.0001). “Healthy” HTX patients, even in presence of impaired global biventricular myocardial deformation, show normal amplitude of LV twist and in turn EF. In addition, probably due to regional differences in wall stress, a LV base-apex gradient of these subclinical systolic dysfunction is detectable. Finally an early impaired LV diastolic filling due to delayed untwisting related to prolonged twist is also evident.