Influence of body mass index on outcomes after minimal-access aortic valve replacement through a J-shaped partial upper sternotomy.
BACKGROUND
Minimal-access aortic valve replacement (MAAVR) may reduce post-operative blood loss and transfusion requirements, decrease post-operative pain, shorten length stay and enhance cosmesis. This may be particularly advantageous in overweight/obese patients, who are at increased risk of post-operative complications. Obese patients are however often denied MAAVR due to the perceived technical procedural difficulty. This retrospective analysis sought to determine the effect of BMI on post-operative outcomes in patients undergoing MAAVR.


METHODS
Ninety isolated elective MAAVR procedures performed between May 2006-October 2013 were included. Intra- and post-operative data were prospectively collected. Ordinary least squares univariate linear regression analysis was performed to determine the effect of BMI as a continuous variable on post-operative outcomes. One-way ANOVA and Chi-squared testing was used to assess differences in outcomes between patients with BMI <25 (n = 36) and BMI ≥25 (n = 54) as appropriate.


RESULTS
There was no peri-operative mortality, myocardial infarction or stroke. Univariate regression demonstrated longer cross-clamp times (p = 0.0218) and a trend towards increased bypass times (p = 0.0615) in patients with higher BMI. BMI ≥25 was associated with an increased incidence of hospital-acquired pneumonia (p = 0.020) and new-onset atrial fibrillation (p = 0.036) compared to BMI <25. However, raised BMI did not extend ICU (p = 0.3310) or overall hospital stay (p = 0.2614). Similar rates of sternal wound complications, inotrope requirements and renal dysfunction were observed in both normal- and overweight/obese-BMI groups. Furthermore, increasing BMI correlated with reduced mechanical ventilation time (p = 0.039) and early post-operative blood loss (p = 0.004).


CONCLUSIONS
Our results demonstrate that within the range of this study, MAAVR is a safe, reproducible and effective procedure, affording equivalent clinical outcomes in both overweight/obese and normal-weight patients considered for an isolated first-time AVR, with low post-operative morbidity and mortality. MAAVR should therefore be considered as an alternative surgical strategy to reduce obesity-related complications in patients requiring aortic valve replacement.
Department of Cardiothoracic Surgery, Hammersmith Hospital, London, UK.
Metesh
M
Acharya
Department of Cardiothoracic Surgery, Hammersmith Hospital, London, UK. leanne.harling@imperial.ac.uk.|The Department of Surgery and Cancer, 10th Floor QEQM Building, St Mary's Hospital, Praed St., London, W2 1NY, UK. leanne.harling@imperial.ac.uk.
Leanne
L
Harling
Department of Cardiothoracic Surgery, Hammersmith Hospital, London, UK.
Marco
M
Moscarelli
Department of Cardiothoracic Surgery, Hammersmith Hospital, London, UK.
Hutan
H
Ashrafian
Department of Cardiothoracic Surgery, Hammersmith Hospital, London, UK.
Thanos
T
Athanasiou
Department of Cardiothoracic Surgery, Hammersmith Hospital, London, UK.
Roberto
R
Casula
D000368:Aged; D000369:Aged, 80 and over; D001024:Aortic Valve Stenosis / Q000401:mortality / Q000601:surgery*; D015992:Body Mass Index; D005260:Female; D019918:Heart Valve Prosthesis Implantation / Q000379:methods; D006801:Humans; D007902:Length of Stay; D008131:London; D008297:Male; D008875:Middle Aged; D009765:Obesity; D011183:Postoperative Complications; D012189:Retrospective Studies; D056346:Sternotomy / Q000379:methods; D016896:Treatment Outcome
Aortic valve replacement; Cardiac surgery; Minimal access; Minimally invasive