Page 37 - ADD-ON ABLATION SURGERY IN PATIENTS WITH ATRIAL FIBRILLATION

Health-related quality of life measurements
All patients who completed the questionnaires at one time-point postoperatively,
whether this was at 3, 6 or 12-month follow-up were included in the HrQoL
sub-study. The RAND 36-item Health Survey (SF-36), EQ-5D, VAS and MFI-20
were measured four times. For the SF-36 higher scores define a more favourable 2 health state. Original items scores were weighted according to the manual13.The
EuroQol addresses the VAS and EQ-5D. Higher scores in VAS indicate a more favourable condition of the patient, while higher scores in the EQ-5D denote a more unfavourable condition.The MFI-20 consists of five scales; for each scale an overall score was calculated ranging from 0 to 20, with higher scores indicating a higher degree of (scale-specific) fatigue.At first, per questionnaire scale a repeated measure ANOVA was performed, using ‘time’ as a four classes within-patients factor and‘treatment group’ as a dichotomous between-patients factor.Interaction between both factors was defined as treatment group differences in linear time- trend within one year. The Kolmogorov-Smirnov (K-S) test for normality of distribution was calculated for the overall linear trend in the scale measurements throughout the 1-year follow-up. By applying repeated measures ANCOVA, preliminary results were found which correct the intermediate ANOVA results for pre-operative scale scores. Other confounding factors and/or covariates at baseline, which were entered into the model were: type of operation (CABG +/-valve, other), gender, age and type of AF. These extended ANCOVA models were performed by multiple dummy-regression analysis with the 1-year linear trend in a scale as ‘dependent’ variable and ‘treatment group’ and confounding factors and/or covariates as predictors. For each scale a final regression model was computed, containing next to the effect of ‘treatment group’, all confounders with statistically significant effects on the linear scale trend.Variance explained in the final model is presented in the tables and the p-value of the treatment group effect is given.A p-value of less than 0.05 was considered statistically significant. All data analyses were performed with SPSS version 15.0 (SPSS Inc. Chicago IL).
Results
Background characteristics
132 patients completed the HrQoL questionnaires at a minimum of one time- point during follow-up. No statistically significant differences in demographic
Quality of life after cardiac surgery
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