Preoperative visceral fat area measured using computed tomography is a robust predictor of postoperative skeletal muscle loss following cardiovascular surgery, with visceral obesity linked to heightened systemic inflammation potentially accelerating muscle degradation through proinflammatory pathways.
Key Findings
Results
The majority of patients undergoing elective cardiovascular surgery were classified as having visceral obesity.
159 patients were included in the final analysis.
69.2% of patients were classified as having visceral obesity.
The study was conducted at a Japanese institution from May 2020 to December 2023.
All surgeries were elective cardiovascular procedures.
Results
Preoperative visceral fat area was significantly correlated with peak postoperative C-reactive protein levels.
The correlation coefficient between visceral fat area and peak postoperative CRP was r = 0.361.
Subcutaneous fat area showed no significant correlation with peak postoperative CRP levels.
CRP was used as an indicator of systemic inflammatory response during the perioperative period.
This suggests visceral fat specifically, not fat in general, drives perioperative inflammation.
Results
Preoperative visceral fat area was significantly correlated with postoperative skeletal muscle loss as measured by change in psoas muscle area.
The correlation coefficient between visceral fat area and change in psoas muscle area was r = -0.374.
Subcutaneous fat area showed no significant correlation with change in psoas muscle area.
Skeletal muscle loss was assessed by the change in psoas muscle area between the preoperative period and the first postoperative week.
The negative correlation indicates that greater visceral fat area was associated with greater muscle loss.
Results
Higher preoperative visceral fat area was independently associated with postoperative skeletal muscle loss in multivariate logistic regression analysis.
Odds ratio for visceral fat area: OR 1.01 (95% CI: 1.00–1.02).
The model was adjusted for age, body mass index, operative time, preoperative CRP level, EuroSCORE II, and preoperative 6-minute walk distance.
Subcutaneous fat area was not significantly associated with postoperative skeletal muscle loss (OR: 1.01; 95% CI: 0.99–1.02).
The differential association between visceral and subcutaneous fat highlights the specific metabolic role of visceral adiposity.
Methods
Computed tomography-based body composition analysis was used to assess visceral fat area, subcutaneous fat area, and psoas muscle area as indicators of skeletal muscle mass.
Preoperative CT was used to calculate visceral fat area (VFA), subcutaneous fat area (SFA), and psoas muscle area (PMA).
Psoas muscle area served as the indicator of skeletal muscle mass.
Postoperative assessment of psoas muscle area was conducted within the first postoperative week.
The study design was a retrospective cohort study.
Discussion
Visceral obesity may accelerate postoperative muscle degradation through proinflammatory pathways.
Patients with visceral obesity experience an amplified systemic inflammatory response during the perioperative period.
Visceral obesity has been linked to increased infection risk in the perioperative setting.
The authors propose that heightened systemic inflammation linked to visceral obesity may drive muscle degradation via proinflammatory pathways.
Significant skeletal muscle loss following invasive cardiovascular surgery was identified as a considerable clinical challenge.