The Impact of Obesity on the Outcome of Surgical Repair for Acute Type A Aortic Dissection

Objectives: A paradox of lower morbidity and mortality in obese patients undergoing cardiac surgery has been described. This study aims to evaluate the effect of obesity on short- and long-term outcomes after surgical treatment for acute Type A aortic dissection (AAD).

Methods: In total 636 patients operated for AAD between June 2004 and June 2018 were identified in our institutional database. Patients were analyzed according to four body mass index (BMI) (kg/m²) groups (normal: BMI ≤ 25, n = 231; overweight: >25 BMI ≤ 30, n = 256; obese: >30 BMI ≤ 40, n = 133; and morbidly obese: BMI >40, n = 16). Patients’ demographics, comorbidities, operative details, postoperative course, short- and long-term outcomes were compared between these groups.

Results: Morbidly obese patients were significantly younger at the time of AD compared with normal patients (59 ± 12 vs. 63 ± 15; p < 0.001). Obese patients demonstrated a significantly higher rate of hypertension (p = 0.005) and diabetes (p = 0.001), all other comorbidities were similar. The clinical status at the time of presentation showed identical Penn classifications in all groups (p = 0.753), only peripheral malperfusion was more frequently found in morbidly obese and obese patients (31 and 14%) compared with overweight and normal patients (11 and 9%, p = 0.042). No differences were found regarding the operative techniques and times or ventilation time, intensive care or hospital stay duration. In-hospital death was significantly higher in morbidly obese and obese patients (18.8 and 14.3%) compared with overweight and normal patients (11.3 and 7.8%, p = 0.038). During long-term follow-up, no differences according to the BMI groups were found among the hospital survivors (p = 0.620).

Conclusion: Diabetes and hypertension are known comorbidities of obesity and could be responsible for the premature occurrence of aortic dissections in overweight patients. Although in-hospital mortality in obese patients was increased, obesity after discharge from hospital no longer played a role in long-term survival. Immediate surgical therapy and close postoperative follow-up are essential for the treatment of patients with type A dissection, regardless of their body weight.

No conflict of interest has been declared by the author(s).