Study Population and Cohort Design
Using convenient sampling method, we retrospectively analyzed clinical,
hemodynamic, and echo-cardiographic data of consecutive 893 patients who
underwent MVR between 2005 and 2015 at the Second Affiliated Hospital of
Harbin Medical University were involved between2005 and 2015. The
patients’ cardiologists and cardiac surgeons individually made the
decision to undergo either surgical intervention or medical management.
For study inclusion, patients who underwent MVR must have met the
following criteria: 1) ≥18 years, 2) mild/moderate FTR, 3) MVR conducted
by the first cardiac surgeon visited, and 4) available complete data.
Criteria for patient exclusion were: 1) existing congenital heart
disease, myocardiopathies, infective endocarditis, or organic TV disease
with inadequate pulmonary artery systemic pressure (PASP), 2) no
additional cardiac surgery received during the follow-up period, 3) had
symptoms of right heart failure(RHF), and 4) incomplete follow-up data.
Of course, they did have at least one
measures of FTR every year during the
five years of follow-up. FTR were measured at any of these time points
if they subsequent visited at any point between the current time point
and the prior pre-specified time point. At the same time, the sample
size was estimated, and weighing the requirement that the group
development model sample size should be 300-500 cases to ensure the
model stability according to the logical proportional risk regression
model. Based on these criteria, the study ultimately examined 378
patients (Figure. 1). The average number of examinations was 8.7, and
the average time interval between examinations was one year during the
whole follow-up period.