Statistical analysis
All analysis were performed with Stata software version 15. Categorical
data were described as absolute and percentage (%) values. Continuous
normal distributed variables were expressed as mean ±standard
deviation (SD), while continuous not-normal variables were reported as
median and [25th percentile; 75th percentile]. To assess normal
distribution Shapiro-Wilk test was employed. Kaplan-Meier estimates were
used to analyze long-term survival. Cumulative incidence function (CIF)
was computed for recurrence of aortic valve regurgitation (≥3+), aortic
valve stenosis ( ≥3+), with death as competing risk. Spaghetti plots
were used to support visual assessment of the longitudinal trajectory of
the degree of Aortic valve regurgitation and Aortic valve stenosis for
each individual over time. In particular, a spaghetti plot shows for
each patient the values for the repeated outcome measure (aortic valve
stenosis and aortic valve regurgitation on vertical axis) versus time
(horizontal axis) and connects the dots chronologically, using lines of
uniform color and intensity for each subject. A p-value of less than
0.05 was employed to define statistical significance.