Objectives: We evaluated the impact of inducing false lumen (FL) thrombosis via coil embolization during repair of type B thoracoabdominal aortic (TAA) dissections. Methods: Since 2007, 26 patients underwent treatment of type B TAA dissections for aneurysm formation (n = 18, 69%), unremitting pain (n = 11, 42%), or rupture (n = 6, 27%). All thoracic endovascular aneurysm repair (n = 21, 81%) and endovascular aneurysm repair (n = 6, 19%) patients underwent coverage of all fenestrations along the descending thoracic aorta or the infrarenal aorta/iliac arteries. During the procedures, transfemoral access was obtained into both true lumen and FL; the stent grafts were implanted in the true lumen, and a cardioMEMS Endosure wireless pressure sensor as well as coils were packed in the FL of the thoracic or abdominal aorta/iliac arteries. The ratio of “FL to systemic pressure” measurements were recorded at systolic, diastolic, mean, and pulse pressure index at the time of implantation, at 1 month and every 6 months thereafter, and computed tomography angiography (CTA) was obtained at similar intervals. Results: Technical success was obtained in all procedures; completion arteriogram did not indicate contrast filling into the FL. Follow-up 6-month and 1-year CTA indicated several significant findings: marked FL thrombosis in 22 patients (85%), FL remodeling with >5-mm reduction in maximum diameter in 17 patients (65%), and none of the patients had an increase in FL maximum diameter. All systolic, diastolic, mean, and pulse pressure index ratios of “FL to systemic pressures” were significantly reduced in 23 patients (88%) at 6 months and 1 year. No patients developed spinal cord ischemia, there were no significant outcome differences in acute and chronic TAA dissections, and the 30-day mortality was 3.8%. Conclusions: FL embolization during endovascular management of acute and chronic type B TAA dissections is safe and effective in reducing FL pressures and maximum diameter and can be a valuable alternative in management of high-risk TAA patients.