Changes in True and False Lumen Pressures During Closure of the Primary Tear in Aortic Dissection

BACKGROUND: To further validate the pressure change within the true (TL) and false lumens (FL), we conducted intraoperative pressure measurements. AIMS: This study aimed to evaluate intraoperative pressure changes within TL and FL in patients with TBAD undergoing TEVAR. METHODS: This study analyzed a cohort of 23 patients with type B aortic dissection (TBAD) who underwent thoracic endovascular aortic repair (TEVAR) at a single institution between 2021 and 2024. Intraoperative pressure measurements were recorded to evaluate changes in the TL and FL at various levels. Additionally, blood pressure waveforms and digital subtraction angiography of both the TL and FL were assessed. RESULTS: During TEVAR in 23 patients with TBAD, intraoperative measurements showed a significant reduction in FL pulse pressure difference postoperatively (40.3 ± 20.5 to 25.3 ± 14.9, p < 0.001), with no significant change in the TL. Stratified analysis revealed a significant reduction in FL pulse pressure difference in chronic-phase patients (45.0 ± 20.9 to 28.9 ± 17.5, p = 0.002). Additionally, 73.9% of patients had higher systolic pressure in TL with an earlier systolic peak, multivariable analysis identified more visceral arteries originating from FL (OR = 0.02, 95% CI = 0.01-0.47) and FL being closer to the spine (OR = 0.05, 95% CI = 0.01-0.77) as factors associated with higher FL systolic pressure. During follow-up, one patient died, and two required reintervention for aortic enlargement. CONCLUSIONS: The involvement of branch arteries is highly correlated with elevated false lumen systolic pressure in patients, and TEVAR can effectively change FL pressure.