Page 14 - Journal of Structural Heart Disease Volume 5, Issue 2

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Original Scientific Article
Table 1. Patient demographics
None 0 Trace I Mild II Mild to Moderate III Moderate IV Severe V
were defined from preoperative TAVR evaluation findings. Paravalvular leak (PVL) and postoperative LVEF (LVEF1-day) reflect TTE findings on postoperative day 1. Using a previously described research-oriented PVL grading scheme [25], PVL was assigned a value according to Table 1. The 30-day LVEF (LVEF30-day) was determined between 5 days and 3 months following TAVR. Postoperative NYHA class heart failure was de- fined by symptom burden at 30-day follow-up, which occurred between 21 days and 3 months following hospital discharge. When available, radiation expo- sure was quantified by dose area product (DAP), air kerma, and fluoroscopy time.
Definition of outcomes
Subgroups
Subgroup analysis was performed on selected de- mographic and procedural characteristics. Patients were categorized by BMI <20, 20 to <30, or ≥30$\ frac{\text{kg}}{m^{2}}$; STS risk score <3, 3 to 8, or >8%; and valve size implanted: small (23 mm Sapien XT/Sapien 3 or 23/26 mm CoreValve Evolut), medium (26 mm Sapien XT/Sapien 3 or 29 mm CoreValve Evo- lut), or large (29 mm Sapien XT/Sapien 3).
Statistical analysis
All statistical analysis was performed using SPSS software (25.0, SPSS Inc., Chicago, IL, USA). Normal- ly distributed continuous variables were presented as mean ± SD, and compared using the two-tailed Student’s t-test coupled with Levene’s test for ho- mogeneity of variance. Non-normally distributed continuous variables were presented as median (25th to 75th interquartile range), and were analyzed with the Mann-Whitney U test. Categorical variables were reported as frequency (%), and compared using the chi-square statistic, Fisher’s exact test, or likelihood ratio, where appropriate. The Spearman’s rank cor- relation coefficient was used in the univariate analy- sis of non-normally distributed continuous variables. Hazard ratios for the PAS group with two-sided 95% confidence intervals were generated using a Cox proportional-hazards model with the MAS group as the reference. In the subgroup analysis, hazard ratios were computed for the composite safety outcome of any adverse event at 30 days. Binary logistic regres- sion was used to compute P-values for interaction between the subgroup variable and the composite safety outcome. Event free survival was compared between groups using the composite safety outcome of any adverse event at 30 days. Event free and cu- mulative survival curves were approximated using the Kaplan-Meier method, and event rates compared with the log-rank test. All tests were 2-sided, and a P-value <0.05 signified statistical significance.
Results
Baseline characteristics
Of the 101 TAVR cases reviewed, 24 patients were in the PAS group and 77 in the MAS group. Baseline characteristics were well balanced between groups
Degree
Grade
Where appropriate, clinical outcomes were de- fined according to the Valve Academic Research Con- sortium-2 standardized definitions [26]. Mortality was assessed at 30 days and 1 year. All other outcomes were measured at 30 days, including ischemic stroke, life threatening or major bleeding, vascular compli- cation requiring intervention, pacemaker implanta- tion, and rehospitalization. Life threatening or major bleeding was defined using a packed red blood cell transfusion threshold ≥3 units during hospitalization, as previously described [26]. A vascular complication was noted to be any post-procedure access site inter- vention. The safety endpoint of excessive intraopera- tive radiation exposure was defined as a DAP greater than 1 standard deviation (SD) above the mean DAP for all patients (DAP > 13310 cGy*cm2). The dichoto- mous composite safety outcome was defined as the occurrence of any of the above adverse events at 30 days, including excessive intraoperative radiation ex- posure or the presence of moderate or severe PVL.
Ahmed B. et al.
TAVR Using Portable Fluoroscopy