Role of novel predictive factors on clinical outcome after transcatheter aortic valve replacement

In Chapter 2 we investigated the incidence, predictors, and prognostic effect of delirium on outcome
after TAVR. Interestingly, we observed that delirium occurs among 13.4% of patients
undergoing TAVR, and more commonly among individuals after nontransfemoral TAVR.
Moreover, delirium following TAVR was associated with longer hospital stay irrespective of
periprocedural complication, and postoperative mortality after transfemoral TAVR access
when adjusted for possible confounding factors.

Chapter 3 we gave a comprehensive review and meta-analysis of the literature on the incidence of
POD after TAVR. The pooled incidence of delirium after TAVR was 8.1%, more frequently
among nontransfemoral access compared with transfemoral access (i.e., 21.4% vs. 7.2%,
respectively). Interestingly, using a specific measure for classifying delirium such as Confusion
Assessment Method, an even higher incidence rate of POD after TAVR was identifiable (i.e.,
13.5%) (25).

Interestingly, in Chapter 4 we observed an association between the
number of cerebral DWI-lesions and POD after TAVR. Although cerebral DWI-lesions may
affect the whole brain after TAVR, we observed more new DWI-lesions in the brain areas
supplied by anterior cerebral artery among patients with delirium. Furthermore, delirium
occurs commonly with other periprocedural complications after TAVR, therefore the true
effect of cerebral DWI-lesions on delirium occurrence was unknown (32). In this chapter,
after stratification of the data according to the presence of periprocedural complications (e.g.,
infection, cerebral ischemic stroke, paravalvular aortic regurgitation, cardiac conduction
abnormalities, atrial fibrillation, vascular or bleeding complication), we observed more
cerebral DWI-lesions in patients with POD after uncomplicated TAVR, suggesting a possible
contribution of these lesions to the development of delirium after TAVR.

In Chapter 5 we explored the effect of TAVR on early and mid-term
cognition outcome after TAVR using comprehensive neurocognitive batteries. Overall, we
observed an improvement in immediate recall memory at 4 months follow-up after TAVR.
Interestingly, this change was more often seen among patients who had lower preprocedural
cognitive scores as compared with patients with average cognitive scores at baseline. Future
studies are required to investigate predictive factors of cognitive decline, and ways to improve
the management of patients who develop cognitive decline during the follow-up after TAVR.

In Chapter 6 and 7 we evaluated the prognostic effect of preprocedural body mass index and smoking status on outcomes after TAVR. In both studies,
we observed paradoxical associations between these variables and mortality outcome after
TAVR among patients undergoing TAVR. Since TAVR indications are expanding towards
lower risk patients, larger and well-designed studies are needed to assess the effect of these
variables on outcomes after TAVR.