The Reoperative Aortic Root: Degenerative Failure vs. Infectious Destruction – Outcomes of The “True Redo-Root” Reconstruction Rita K. Milewski, Arminder S. Jassar, Alberto Pochettino, Wilson Y. Szeto, Nimesh D. Desai, Patrick J. Moeller, Joseph H. Gorman, Robert C. Gorman and Joseph E. Bavaria Division of Cardiovascular Surgery University of Pennsylvania, Philadelphia, PA Aortic Surgery Symposium 2010, April 29-30, New York.

Objective Prosthetic root failure occurs as a result of either an infectious process or from degenerative dysfunction of the prosthetic aorta, valve, or both The objective of this study is to identify the indications and examine outcomes for reoperative aortic root reconstruction, stratified by degenerative or infectious cause of prosthetic root failure

Study Cohorts and Methods From June June 2009, 1011 aortic root procedures were performed at the University of Pennsylvania 63 patients had undergone a prior Aortic Root Reconstruction – Aortic root replacements in the setting of redo sternotomy for prior AVR or prior ascending aortic surgery were excluded All Aortic Root Procedures were stratified by cause of prosthetic root failure: –Degenerative dysfunction N=29 –Infection N=34 Retrospective subgroup analysis performed utilizing STS-NCD and Penn Aortic Database Degenerative Root Failure (N = 29) (46%) Infection (Treated) (N =14) (22.2%) Infection (Active) (N = 20) (31.7%)

Incidence of True Redo Aortic Root Reconstruction is progressively increasing (June – Dec)(Jan-June) Annual Procedures Performed ( )

Preoperative Characteristics Patients in the infection cohort were older and had a higher incidence of CVA as compared to patients in the degenerative failure group. No significant difference in other major co-morbidities. Preoperative Diagnosis All N = 63 (%) Degenerative Failure N=29 (%) Infection N=34 (%) P-value Degenerative Failure vs. Infection Age (Mean ± SD)50.1 ± ± ± Male48 (76.2%)21 (72.4%)27 (79.4%)0.56 HTN41 (65.1%)18 (62.1%)23 (67.6%)0.79 DM5 (7.9%)2 (6.9%)3 (8.8%)1 CVA13 (20.6%)013 (38.2%)<0.01 Chronic Lung Disease7 (11.1%)5 (17.2%)2 (5.9%)0.23 Renal Failure with dialysis2 (3.2%)2 (6.9%)00.21 Previous MI13 (20.6%)5 (17.2%)8 (23.5%)0.76 Arrythmia/ Heart Block23 (36.5%)9 (31%)14 (41.2%)0.44

Operative Timing and Status Variable All N= 63 Degenerative Failure N=29 Infection N=34 P-value Years since previous operation (Mean ± SD) 6.2 ± ± ± 4.4<0.01 Urgent/ Emergent operation N (%) 23 (36.5%) 6 (20.7%) 17 (50%) 0.02  Time to reoperation is significantly reduced in presence of infection.  Incidence of urgent operations is higher in the infection cohort.

All 63 patients underwent aortic root replacement. 27 patients underwent circulatory arrest and hemiarch reconstruction Concomitant ProceduresN (%) Hemiarch27 (42.9%) MV Replacement5 (7.9%) MV annuloplasty/ reconstruction12 (19%) CABG5 (7.9%) Other -TV Repair/ Ring, ASD/PFO closure, VSD Closure 7 (11.1%) All Mean ± S.D. Degenerative Failure Mean ± S.D. Infection Mean ± S.D. P-value Degenerative Failure vs. Infection Perfusion time306.9 ± ± ± Aortic Cross clamp time ± ± ± DHCA time31.3 ± ± ± Although operative times were longer in the infection group, these differences were not significant Intraoperative Variables And Concomitant Procedures

Explanted Prosthetic Roots Stratified by Infective or Degenerative Process * - Homograft Failure = Homograft (n=28) or Autograft (Ross) (n=4) degeneration § - Conduit Failure = Dehiscence /disruption/ pseudoaneurysm of conduit ¶ - Valve failure = Prosthetic valve AI/AS TOTAL EXPLANTED PROSTHETIC ROOTS INFECTION (N=34) DEGENERATIVE PROSTHETIC ROOT FAILURE (N=29) Homograft/Autograft failure * (N=21) Conduit Failure § (N=5) Valve failure ¶ (N=3) Mechanical (N= 15)10 (29.4%)-4 (80%)1 (33.3%) Stentless Bioroot (N=14)12 (35.3%)--2 (66.7%) Biologic Composite (N=2)2 (5.9%)--- Homograft/ Autograft(N=32)10 (29.4%)21(65.6%)1 (20%)-  Infection was the most common indication for prosthetic root explant (54%)  Mechanical composite roots comprised only 29.4% of roots explanted for infection  Of the explanted homografts, 65.6% were explanted due to homograft deterioration and 31.2% were explanted because of infection All prosthetic roots are susceptible to infection Bioroot or Homograft did not provide absolute protection from subsequent infection

Implanted Reoperative Prosthetic Roots Stratified by Infectious or Degenerative Process  Mechanical Composite root was the most common prosthetic implanted in both degenerative prosthetic failure (72.4%) and infection (55.9%)  Biologic options were more frequently used in infected cases (44.1%) than in degenerative cases (27.6%)  Homograft was used infrequently and employed solely for infection INFECTION N=34 (%) DEGENERATIVE PROSTHETIC ROOT FAILURE (N=29) Homograft/Autograft failure N=21 (%) Conduit Failure N=5 (%) Valve failure N=3 (%) Total Implanted Prosthetic Roots Mechanical (N= 40) 19( 55.9%)15 (71.4%)4 (80%)2 (66.7%) Stentless Bioroot (N=8) 5 (14.7%)3 (14.3%)-- Biologic Composite (N=10) 5 (14.7%)3 (14.3%)1 (20%)1 (33.3%) Homograft (N=5) 5 (14.7%)---

Post-op Event All (%)or Mean± S.D (N = 63) Degenerative (%) or Mean ± S.D (N = 29) Infectious (%) or Mean ± S.D (N=34) P- value 30 Day/In- Hosp Mortality3 (4.8%) 03 (8.8%)0.24 Freedom from all Complications29 (46%)18 (62.1%)11 (32.4%)0.02 Length of Stay (days)15.7 ± ± ± Additional Sternal Procedure5 (7.9%)05 (14.7%)0.056 Stroke (Permanent)3 (4.8%)1 (3.4%)2 (5.9%)1 Stroke (Transient)3 (4.8%)03 (8.8%)0.24 Re-op for Bleed/Tamponade6 (9.5%)1 (3.4%)5 (14.7%)0.21 Heart Block8 (12.7%)2 (6.9%)6 (17.6%)0.27 Prolonged Ventilation16 (25.4%)5 (17.2%)11 (32.4%)0.25 Renal Failure requiring Dialysis2 (3.2%)02 (5.9%)0.5 Sepsis6 (9.5%)1 (3.4%)5 (14.7%)0.21 Death ± Stroke ± Dialysis ± Heart Block15 (7.9%)3 (4.8%)12 (35.3%)0.036  Overall mortality = 4.8%; 46% patients had no complications  Presence of infection significantly increases overall incidence of complications, postoperative length of stay and composite risk for a major complication (Death, Stroke, Dialysis or Heart Block) Postoperative Outcomes

N at Risk (All) Overall survival at 6 yrs is 82.3% Reoperative Aortic Root Survival Degenerative Dysfunction All Infection  Infection = 74.4%  Degenerative = 95.5%

Conclusions  Infection and homograft degeneration were the major etiology for redo-aortic root replacement  Mechanical valved conduit was the most common prosthetic type used for redo-aortic root replacement  Presence of infection increases risk for major complications  Re-operative aortic root replacement can be safely performed with low perioperative morbidity and mortality and yield good mid-term survival