Serial CT Volume and Thrombus Length Measurements after Endovascular Repair of Stanford Type B Aortic Dissection

Abstract

Purpose:

To evaluate the outcome of stent-graft placement in Stanford type B aortic dissection using contrast-enhanced spiral computed tomographic (CT) measurements of true and false lumen volumes and thrombus length.

Methods:

Among 18 consecutive patients (13 men; mean age 60 years, range 44–79) who underwent endovascular repair of Stanford type B dissection, 12 completed at least a 12-month follow-up, which included CT measurements of true and false lumen volumes and thrombus lengths prior to discharge and at 6 and 12 months postimplantation. Volumes were assessed in 3 different aortic segments (A1, A2, A3) extending from the proximal attachment site of the prosthesis to the aortic bifurcation. In addition, thrombus length was measured to evaluate the influence of clot formation on outcome of the false lumen volume.

Results:

Mean follow-up was 27 months (range 12–60). Within 12 months, mean true lumen volumes showed statistically significant increases in the A1 (p<0.001) and A2 (p=0.003) segments; false lumen volumes showed a significant decrease in the A1 segment (p=0.002) but an insignificant increase in the A2 segment. No substantial volume changes were observed in the A3 segment. Extension of clot formation in the false lumen varied among patients and over time. Length of stent-grafts, percentage of stented dissection length, or visceral arteries originating from the false lumen did not significantly influence thrombus development, nor did these parameters or thrombus formation distal to the prosthesis have a relationship to false lumen volumes.

Conclusions:

Volumetric analysis after endovascular repair of Stanford type B dissection shows optimal technical outcome in the stented segment, whereas the false lumen in the segment immediately adjacent to the stent-graft seems to be a vulnerable area. Extension of clot formation beyond the endograft seems to be no reliable predictor of outcome.

Keywords

thoracic aorta type B dissection stent-graft volumetric analysis true lumen false lumen thrombosis

Get full access to this article

View all access options for this article.

References

Kouchoukos

Dougenis

. Surgery of the thoracic aorta. N Engl J Med. 1997; 336: 1876–1888.

Hagan

Nienaber

Isselbacher

. The International Registry of Acute Aortic Dissection (IRAD): New insights into an old disease. JAMA. 2000; 283: 897–903.

Coselli

Plestis

La Francesca

. Results of contemporary surgical treatment of descending thoracic aortic aneurysms: Experience in 198 patients. Ann Vasc Surg. 1996; 10: 131–137.

Svensson

Hess

Coselli

. Influence of segmental arteries, extent, and atriofemoral bypass on postoperative paraplegia after thoracoabdominal aortic operations. J Vasc Surg. 1994; 20: 255–262.

Coselli

LeMaire

Figueiredo

. Paraplegia after thoracoabdominal aortic aneurysm repair: Is dissection a risk factor? Ann Thorac Surg. 1997; 63: 28–36.

Iguchi

Tabayashi

. Outcome of medically treated Stanford type B aortic dissection. Jpn Circ J. 1998; 62: 102–105.

Glower

Fann

Speier

. Comparison of medical and surgical therapy for uncomplicated descending aortic dissection. Circulation. 1990; 82(5 Suppl): IV39–IV46.

Masuda

Yamada

Morooka

. Prognosis of patients with medically treated aortic dissections. Circulation. 1991; 84(5 Suppl): III7–III13.

Miller

. The continuing dilemma concerning medical versus surgical management of patients with acute type B dissections. Semin Thorac Cardiovasc Surg. 1993; 5: 33–46.

10.

Jex

Schaff

Piehler

. Early and late results following repair of dissections of the descending thoracic aorta. J Vasc Surg. 1986; 3: 226–237.

11.

Wheat

. Current status of medical therapy of acute dissecting aneurysms of the aorta. World J Surg. 1980; 4: 563–569.

12.

Dake

Kato

Mitchell

. Endovascular stent-graft placement for the treatment of acute aortic dissection. N Engl J Med. 1999; 340: 1546–1552.

13.

Nienaber

Fattori

Lund

. Nonsurgical reconstruction of thoracic aortic dissection by stent-graft placement. N Engl J Med. 1999; 340: 1539–1545.

14.

Czermak

Waldenberger

Fraedrich

. Treatment of Stanford type B aortic dissection with stent-grafts: Preliminary results. Radiology. 2000; 217: 544–550.

15.

Kato

Shimono

Hirano

. Midterm results of stent-graft repair of acute and chronic aortic dissection with descending tear: The complication-specific approach. J Thorac Cardiovasc Surg. 2002; 124: 306–312.

16.

Lopera

Patino

Urbina

. Endovascular treatment of complicated type-B aortic dissection with stent-grafts: Midterm results. J Vasc Interv Radiol. 2003; 14: 195–203.

17.

Kato

Hirano

Kawaguchi

. Aneurysmal degeneration of the aorta after stent-graft repair of acute aortic dissection. J Vasc Surg. 2001; 33: 513–518.

18.

Tiesenhausen

Amann

Koch

. Endovascular stent-graft repair of acute thoracic aortic dissection—early clinical experiences. Thorac Cardiovasc Surg. 2001; 49: 16–20.

19.

Schneider

. Assessment of risk factors and surgical outcome. Surg Clin North Am. 1983; 63: 1113–1126.

20.

Czermak

Fraedrich

Schocke

. Serial CT volume measurements after endovascular aortic aneurysm repair. J Endovasc Ther. 2001; 8: 380–389.

21.

Hutschala

Fleck

Czerny

. Endoluminal stent-graft placement in patients with acute aortic dissection type B. Eur J Cardiothorac Surg. 2002; 21: 964–969.

22.

Wheatley

Rosenfield

Heller

. Validation of a technique of computer-aided tumor volume determination. J Surg Res. 1995; 59: 621–626.

23.

Singh-Ranger

McArthur

Corte

Della M

. The abdominal aortic aneurysm sac after endoluminal exclusion: A medium-term morphologic follow-up based on volumetric technology. J Vasc Surg. 2000; 31: 490–500.

24.

Singh-Ranger

McArthur

Lees

. A prospective study of changes in aneurysm and graft length after endovascular exclusion of AAA using balloon and self-expanding endograft systems. Eur J Vasc Endovasc Surg. 2000; 20: 90–95.

25.

Nawaratne

Fabiny

Brien

. Accuracy of volume measurement using helical CT. J Comput Assist Tomogr. 1997; 21: 481–486.

26.

Armon

Yusuf

Whitaker

. Thrombus distribution and changes in aneurysm size following endovascular aortic aneurysm repair. Eur J Vasc Endovasc Surg. 1998; 16: 472–276.

27.

Wever

Blankensteijn

Mali

WPTM

. Maximal aneurysm diameter follow-up is inadequate after endovascular abdominal aortic aneurysm repair. Eur J Vasc Endovasc Surg. 2000; 20: 177–182.

28.

Williams

Lee

Hamilton

. The dissected aorta: Part III. Anatomy and radiologic diagnosis of branch-vessel compromise. Radiology. 1997; 203: 37–44.

29.

Gysi

Schaffner

Mohacsi

. Early and late outcome of operated and non-operated acute dissection of the descending aorta. Eur J Cardiothorac Surg. 1997; 11: 1163–1170.

30.

DeBakey

McCollum

Crawford

. Dissection and dissecting aneurysms of the aorta: Twenty-year follow-up of five hundred twenty-seven patients treated surgically. Surgery. 1982; 92: 1118–1134.

31.

Kato

Bai

Sato

. Determining surgical indications for acute type B dissection based on enlargement of aortic diameter during the chronic phase. Circulation. 1995; 92: II107–II112.

32.

Guthaner

Miller

Silverman

. Fate of the false lumen following surgical repair of aortic dissections: An angiographic study. Radiology. 1979; 133: 1–8.

33.

Gaubert

Moulin

Mesana

. Type A dissection of the thoracic aorta: Use of MR imaging for long-term follow-up. Radiology. 1995; 196: 363–369.

34.

White

Ullyot

Higgins

. MR imaging of the aorta after surgery for aortic dissection. AJR Am J Roentgenol. 1988; 150: 87–92.

35.

Ergin

Phillips

Galla

. Significance of distal false lumen after type A dissection repair. Ann Thorac Surg. 1994; 57: 820–825.

36.

Dinsmore

Willerson

Buckley

. Dissecting aneurysm of the aorta: Aortographic features affecting prognosis. Radiology. 1972; 105: 567–572.

37.

Marui

Mochizuki

Mitsui

. Toward the best treatment for uncomplicated patients with type B acute aortic dissection: A consideration for sound surgical indication. Circulation. 1999; 100(19 Suppl): II275–II280.

38.

Juvonen

Ergin

Galla

. Risk factors for rupture of chronic type B dissections. J Thorac Cardiovasc Surg. 1999; 117: 776–786.

39.

Williams

LePage

Lee

. The dissected aorta: Part I. Early anatomic changes in an in vitro model. Radiology. 1997; 203: 23–31.

40.

Pamler

Kotsis

Görich

. Complications after endovascular repair of type B aortic dissection. J Endovasc Ther. 2002; 9: 822–828.

41.

Totaro

Miraldi

Fanelli

. Emergency surgery for retrograde extension of type B dissection after endovascular stent graft repair. Eur J Cardiothorac Surg. 2001; 20: 1057–1058.