Study of criteria for identifying candidate caregivers who are likely to have difficulty in the handling training of implantable ventricular assist devices

Abstract

The standard for destination therapy using implantable ventricular assist devices requires that the Mini-Mental State Examination（MMSE）and Trail Making Test-B（TMT-B）vertical version results must be at least 24 points and 300 seconds or less, respectively, to confirm self-management ability for patients over 65 years old. Although we use the same criteria for older caregiver candidates, there were a certain number of caregiver candidates who were unable to complete the device handling training even when meeting these criteria. In this study, we examined the criteria for identifying caregiver candidates who are likely to have difficulty in the training. This study used the results of MMSE and TMTB（vertical version）in 41 patients with HeartMate3^TM and 31 caregiver candidates who received the device handling training. The subjects who required at least three assessments to pass were classified as the difficulty group. We examined the relationship between the number of assessments and the standard cutoff values（MMSE 24 points, TMT-B 300 seconds）. No statistical correlations were found between the standard cutoff values and the number of assessments. We then used Receiver Operating Characteristic（ROC）analysis to identify a predictive cutoff value. The ROC analysis determined a TMT-B cutoff of 115 seconds（sensitivity 78.6％, specificity 84.5％, AUC 0.83）, which was statistically significant（p＝0.02）. However, the AUC for MMSE was 0.52, and no statistical significance was found（p＝0.82）. Therefore, a TMT-B（vertical version）result of 115 seconds is a useful criterion for identifying caregiver candidates likely to have difficulty in device handling training.