Abstract
Background/Introduction
Echocardiography is commonly used in evaluation patients after heart transplantation (HTx). Detecting discrete changes in ventricular function is important but challenging using standard echocardiographic parameters. Furthermore, interpretation of findings are complicated by the fact that data on early possible adaptation is sparse.
Purpose
We sought to detect alterations in biventricular function primarily using speckle tracking derived strain at four time-points during the first year post HTx.
Methods
Fifty HTx patients (40 males, mean age 50±12 years) were prospectively included. Patients were examined 1, 3, 6 and 12 months after HTx using an iE33 platform with a S5–1 transducer and strain analysis was performed offline with a dedicated software: CMQ, Q-lab 10.3 (Philips Healthcare, Eindhoven, NL). Values were compared using paired t-test and expressed as mean±SD, 95% CI.
Results
Regarding left ventricular (LV) parameters no difference were detected between 1 and 12 months. LV ejection fraction (EF) was 58±5% vs. 58±7%, global longitudinal strain (GLS) was −15±5% vs. −16±4% and global circumferential strain (GCS) was −22±7% vs. −21±6% respectively. Conventional parameters of right ventricular (RV) function: Tricuspid annular plane systolic excursion (TAPSE) improved from 12±2 mm at 1 month to 15±5 mm (p<0.01) at 12 months and tricuspid annular systolic velocity (S') improved from 8.1±1.9 cm/s to 9.5±2.7 cm/s (p<0.01) at 12 months. Fractional area change (FAC) remained unaltered. Strain measurements of RV function improved gradually between 1 and 12 months. RV GLS was −15±3% vs. −17±3% (p<0.01) and strain for the RV lateral wall (RVfree) was −15±3% vs. −18±3% (p<0.001) respectively. Progressive improvement in RV strain is illustrated in Fig 1.
Right ventricular strain post HTx
Conclusion
Our data indicate that clinically stable HTx recipients have reached steady state regarding LV function already 1 month after transplantation. This suggests that alterations in LV function parameters after this time-point can be used to detect adverse events.
On the contrary, right ventricular longitudinal function show significant gradual improvement during the first year following HTx indicating that the RV adaptation-process is extended in comparison to the LV.
We found that measurements of LV function at 1 month and RV function at 12 months post HTx are comparable to previously published normal values in clinically stable HTx patients. Nevertheless, further studies addressing possible continuous improvement in RV function beyond 1 year post HTx would be of interest.
Echocardiographic assessment of chamber size and ventricular function during the first year after heart transplantation
