Association between delirium severity and prognosis following Transcatheter aortic valve implantation.

Background: Delirium is associated with patient prognosis after transcatheter aortic valve implantation (TAVI). However, the prognostic impact of subsyndromal delirium, described as an intermediate stage between delirium and normal cognition, is uncertain. The present study aimed to investigate the prognostic impact of delirium severity in patients undergoing TAVI.

Methods and results: We prospectively assessed the delirium status of 1617 consecutive patients who underwent TAVI at Kokura Memorial Hospital using the Intensive Care Delirium Screening Checklist (ICDSC). The patients were divided into the following three groups: no-delirium [ICDSC score 0, n = 1035 (64.0 %)], subsyndromal delirium [ICDSC 1-3, n = 348 (21.5 %)], and delirium [ICDSC 4-8, n = 234 (14.5 %)] groups. A worse delirium status was associated with older age, higher degree of frailty, and higher prevalence of comorbidities, including atrial fibrillation, dementia, and peripheral arterial disease. At 2 years post-procedure with a clinical follow-up rate of 92.6 %, the cumulative all-cause mortality rate was significantly higher in the subsyndromal delirium (21.8 %) (p < 0.001) and delirium (29.1 %) (p < 0.001) groups than in the no-delirium group (11.9 %). After adjusting for pre- and post-procedural confounders, subsyndromal delirium and delirium were associated with an increased mortality risk [adjusted hazard ratio (HR) for subsyndromal delirium, 1.38; 95 % CI, 1.00-1.90; p = 0.049; adjusted HR for delirium, 1.61; 95 % CI, 1.15-2.17; p = 0.006].

Conclusions: Delirium conditions, including delirium and subsyndromal delirium, occurred in more than one-third of patients who had undergone TAVI and were associated with increased mortality.