Severe aortic stenosis (AS) causes left ventricular (LV) afterload and subendocardial ischemia. Despite this, most infants with AS have normal LV ejection fraction (EF). Strain analysis using two-dimensional speckle tracking echocardiography (2DSTE) may identify more sensitive markers of systolic dysfunction. We sought to show changes in LV strain after balloon aortic valvuloplasty (BAV) in infants with AS. Twenty-seven infants ≤ 1 year of age with AS who underwent BAV from 2007 to 2017 were included. Echocardiograms before/after BAV were retrospectively analyzed with 2DSTE. Median age was 29 days (interquartile range 3-52) and LV EF was 64 ± 10%. Global longitudinal strain (GLS) significantly improved post-BAV (- 17 ± 5 vs. - 20 ± 4%, p = 0.001) with no difference in global circumferential strain. Peak longitudinal strain was abnormal at the inferoseptal base and mid-ventricle (- 15 ± 6 and - 17 ± 5 = 7%, respectively) and significantly improved in the basal and mid-anterolateral segments (- 17 ± 5 vs. - 21 ± 5%, p < 0.01; - 17 ± 6% vs. - 20 ± 5%, p = 0.01, respectively). Five (20%) patients underwent reintervention, and had significantly higher peak-to-peak pre and post-BAV AS gradients (86 ± 14 vs. 61 ± 20 mmHg, p = 0.02; 33 ± 17 vs. 21 ± 10 mmHg, p = 0.04, respectively). In conclusion, longitudinal strain is abnormal in infants with AS and improves to previously published normal values after BAV.
Keywords: Aortic stenosis; Balloon aortic valvuloplasty; Infant; Left ventricle; Strain.