Remodeling of the Remnant Aorta after Acute Type A Aortic Dissection Surgery Are Young Patients More Likely to Develop Adverse Aortic Remodeling of the Remnant Aorta Over Time? Suk Jung Choo¹, Jihoon Kim¹, Sun Kyun Ro², Joon Bum Kim¹, Sung-Ho Jung¹, Cheol Hyun Chung¹, Jae Won Lee¹ 1 Thoracic and Cardiovascular Surgery, Asan Medical Center, College of Medicine, University of Ulsan, Seoul, Korea; 2 Thoracic and Cardiovascular Surgery, Hanyang University Guri Hospital, Hanyang University College of Medicine, Gyeonggi-do, Korea 1
Background Adverse aortic remodeling after acute type A aortic dissection in younger ages may be more extensive in its course than in advanced age 2
Study design - Pre/Post op CT - 2 2 1 3 1 3 3
Method The aortic index segments analyzed in the study were the remnant aortic sinus, aortic arch, and proximal descending aorta 4
Enrollment: Jan 1999 - Dec 2013 190 Acute type A aortic dissection Ascending and/or hemiarch replacement 162 Pre- and postoperative chest CT (+) 124 F/U > 1 month 76.5% 5
Method The patients were divided into two groups according to age Group A Age < 50 yrs Group B Age 50 yrs n 29 95 Mean age (yrs) 42.9 ± 5.5 63.8 ± 7.4 6
Patient demographics and clinical characteristics Characteristics Group A (n = 29) Group B (n = 95) P value Age (y) 42.9 ± 5.5 63.8 ± 7.4 NA Male gender 18 (62.1) 38 (40.0).037 Risk Factors DM 1 (3.4) 3 (3.2) >.999 Hypertension 10 (34.5) 58 (61.1).012 COPD 0 (0.0) 2 (2.1) >.999 Renal failure 0 (0.0) 1 (1.1) >.999 CVD 1 (3.4) 5 (5.3) >.999 Marfan syndrome 3 (10.3) 1 (1.1).040 Bicuspid aortic valve 2 (6.9) 1 (1.1).136 COPD, Chronic obstructive pulmonary disease; CVD, cerebrovascular disease; DM, diabetes mellitus; IMH, intramural hematoma; NA, Not applicable. 7 *Chi-square statistic for overall difference.
Patient demographics and clinical characteristics Characteristics Group A (n = 29) Group B (n = 95) P value Dissection Characteristics.158 * DeBakey I 29 (100.0) 84 (88.4).066 DeBakey II 0 (0.0) 2 (2.1) >.999 IMH (All DeBakey I) 0 (0.0) 9 (9.5).115 Malperfusion Cerebral 1 (3.4) 4 (4.2) >.999 Visceral 1 (3.4) 1 (1.1).415 Peripheral 2 (6.9) 5 (5.3).665 Previous cardiac or aortic surgery 0 (0.0) 1 (1.1) >.999 COPD, Chronic obstructive pulmonary disease; CVD, cerebrovascular disease; DM, diabetes mellitus; IMH, intramural hematoma; NA, Not applicable. 8 *Chi-square statistic for overall difference.
Operative data Tear site location Variable Group A (n = 29) Group B (n = 95) P value.007 * Ascending aorta 14 (48.3) 53 (55.8).477 Aortic arch 3 (10.3) 16 (16.8).559 Descending thoracic aorta 2 (6.9) 4 (4.2).624 Combined 4 (13.8) 5 (5.3).212 Unidentified or unrecorded 6 (20.7) 17 (17.9).735 Tear site exclusion 18 (62.1) 74 (77.9).088 Aorta replacement.771 * Ascending 5 (17.2) 14 (14.7).771 Ascending+hemiarch 24 (82.8) 81 (85.3).771 ACC, Aortic cross-clamp; ACP, antegrade cerebral perfusion; AVP, aortic valvuloplasty; CABG, coronary artery bypass grafting; CPB, cardiopulmonary bypass; Fem-fem bypass, femorofemoral bypass grafting; RCP, retrograde cerebral perfusion; TCA, total circulatory arrest *Chi-square statistic for overall difference. 9
Operative data Variable Group A Group B P (n = 29) (n = 95) value Concomitant surgery.931 * AVP 4 (13.8) 16 (16.8) >.999 CABG 2 (6.9) 3 (3.2).665 Fem-fem bypass 1 (3.4) 4 (4.2) >.999 Others 0 (0.0) 3 (3.2) >.999 Cardiopulmonary bypass CPB time (min) 218.9 ± 86.1 213.7 ± 88.8.780 ACC time (min) 103.7 ± 56.2 106.9 ± 57.1.794 Low body arrest time (min) 25.0 ± 12.0 28.3 ± 13.2.305 TCA 0 (0) 6 (6.3).334 RCP 17 (58.6) 49 (51.6).506 ACP 12 (41.4) 40 (42.1).945 Target temperature ( ) 18.1 ± 4.5 18.2 ± 4.3.917 ACC, Aortic cross-clamp; ACP, antegrade cerebral perfusion; AVP, aortic valvuloplasty; CABG, coronary artery bypass grafting; CPB, cardiopulmonary bypass; Fem-fem bypass, femorofemoral bypass grafting; RCP, retrograde cerebral perfusion; TCA, total circulatory arrest *Chi-square statistic for overall difference. 10
Early outcomes and complications Variable Group A (n = 29) Group B (n = 95) P value Neurologic deficits 2 (6.9) 6 (6.3) >.999 Pneumonia 4 (13.8) 13 (13.7) >.999 Renal failure 3 (10.3) 22 (23.2).132 Duration of mechanical ventilation (d) 2.6 ± 2.1 3.9 ± 7.4.324 ICU stay (d) 5.6 ± 4.5 7.4 ± 9.1.321 Hospital stay (d) 16.4 ± 9.5 26.7 ± 30.0.005 In-hospital mortality 1 (3.4) 1 (1.1).415 Aortic reoperation 3 (10.3) 5 (5.3).388 * Root remodeling 0 (0.0) 1 (1.1) Bentall operation 1 (3.4) 0 (0.0) Replacement of total arch 0 (0.0) 1 (1.1) Replacement of DTA 1 (3.4) 1 (1.1) Replacement of TAA 1 (3.4) 1 (1.1) Replacement of total arch and TAA 0 (0.0) 1 (1.1) DTA, Descending thoracic aorta; ICU, intensive care unit; TAA, thoracoabdominal aorta. *Chi-square statistic for overall difference. 11
CT follow up period Overall CT follow up period Median: 36.4 (IQR 14.3 66.1) months Young age Median: 33.4 (IQR 3.9-77.1) months Old age Median: 27.7 (IQR 6.3 54.8) months Mean 53.4 ± 40.9 vs 40.8 ± 32.3 P =.088 12
Size changes of the remnant aorta on the computed tomography scans (mm) Group A (n = 29) Group B (n = 95) Preoperative CT scan Latest CT scan P value Location Preoperative CT scan Latest CT scan P value 41.8 ± 6.0 44.1 ± 7.3.004 Aortic sinus 40.5 ± 6.0 41.0 ± 5.4.370 36.5 ± 6.8 41.3 ± 8.6.010 Aortic arch 38.5 ± 5.0 37.6 ± 8.1.380 36.4 ± 6.6 43.0 ± 11.2.003 Proximal DTA 37.6 ± 4.8 40.6 ± 9.3.002 CT, Computed tomography; DTA, descending thoracic aorta. 13
Size changes of the remnant aorta on the computed tomography scans (mm) Location Group A (n = 29) Group B (n = 95) P value Aortic sinus 41.8 ± 6.0 40.5 ± 6.0.317 Preoperative CT scan Aortic arch 36.5 ± 6.8 38.5 ± 5.0.101 Proximal DTA 36.4 ± 6.6 37.6 ± 4.8.295 Aortic sinus 44.1 ± 7.3 41.0 ± 5.4.039 Latest CT scan Aortic arch 41.3 ± 8.6 37.6 ± 8.1.037 Proximal DTA 43.0 ± 11.2 40.6 ± 9.3.253 CT, Computed tomography; DTA, descending thoracic aorta. 14
Association between age and aortic expansion rates developed by linear regression models 15
Overall Survival Curves 16
Finding summary All index segments of the non-operated remnant aorta in young patients showed significant dilatation over time after acute type A aortic dissection surgery whereas in the older patients only the descending thoracic aorta appeared to significantly dilate 17
Comments The results suggested a more extensive pattern of aortic remodeling in relatively younger patients Extensive surgery should be performed on a need basis- albeit more proactively Close and frequent monitoring Optimal medical treatment should be ensured 18
Limitations Retrospective study How young is young? Measurement error- One observer (JK) blinded to patient-identifying information performed the image analysis F/U period relatively short follow up Etiology? Biopsy studies? 19
Thank you for your attention 20
Q & A 21
Acute AD Type A < 50 y/o (n=83) 50 y/o (n=188) P value Bentall procedure 16 (19.3) 3 (1.6) <.001 Root remodelling 1 (1.2) 4 (2.1) >.999 Total arch replacement 31 (37.3) 36 (19.1) <.002 Jan 1999 - Dec 2013 22
Cause of Death Group A Group B Cardiac tamponade 1 Unknown 2 Tracheostomy obstruction Malignancy 3 Sepsis 1 Unknown 2 n 1 23
Impact of age on late aortic expansion determined by linear regression analyses R 2 Unadjusted Adjusted* Beta Standard P coefficient error value** R 2 Beta Standard P coefficient error value** Aortic sinus 0.072-0.064 0.038 0.098 (0.092) 0.225-0.079 0.035 0.026 (0.020) Aortic arch 0.058-0.159 0.078 0.042 (0.028) 0.296-0.120 0.068 0.079 (0.070) Proximal DTA 0.073-0.114 0.075 0.135 (0.101) 0.102 0.009 0.075 0.907 (0.892) DTA, descending thoracic aorta. *Multivariable linear regression analyses were performed. Covariates for multivariable models in addition to age were as follows (selected from univariable analyses that had p values of less than 0.20): (1) Aortic sinus: preoperative sinus diameter, root involvement of aortic dissection; (2) Arch: preoperative arch diameter; (3) Descending aorta: preoperative descending aortic diameter, intramural hematoma and distal extent of aortic dissection. ** Statistical models were further validated by 1000 bootstrap samples (P values in parentheses). 24
Image analysis 25
Conclusion Aorta tends to dilate in a more extensive fashion in young patients after acute AD surgery Extensive surgery should be performed on a need basis- albeit more proactively Close and frequent monitoring Optimal medical treatment should be ensured 26