Challenges in Cardiac Risk Stratification for Bariatric Surgery: A Single-Centre Experience.

BACKGROUND

Preoperative cardiac risk stratification in patients undergoing bariatric surgery is challenged by suboptimal transthoracic echocardiography (ECHO) due to high body mass index (BMI). In this retrospective study, we described the diagnostic yield of technetium-99 m tetrofosmin single-photon emission computed tomography (SPECT) or Myoview compared with ECHO and characterised the potential contribution of imaging-derived information to preoperative decision-making.

METHODS

Retrospective cohort of 66 adults were evaluated for bariatric surgery who underwent SPECT and/or ECHO between 2017 and 2024. Imaging findings, agreement between modalities, downstream angiographic testing and surgical outcomes were analysed using correlation, Bland-Altman plot, χ², and logistic regression.

RESULTS

Cardiometabolic burden was high (hypertension 60.9%, OSA 57.8%, diabetes 56.3%; coronary artery disease (CAD) 16.7%). Thirty-five (53.0%) underwent surgery. ECHO was attempted in 45/66 (68.2%); image quality was limited in 20/45 (44.4%). SPECT showed reversible ischemia in 13 (19.7%), fixed in 8 (12.1%), and no ischemia in 45 (68.2%). Known CAD was associated with abnormal SPECT (χ²=11.338, p = 0.023). Overall ejection fraction (EF) agreement between ECHO and SPECT was poor among the 40 patients with paired EF measurements.

CONCLUSION

In our high-risk bariatric cohort, ECHO was often limited by image quality, while SPECT provided additional perfusion and gated functional data. However, the retrospective design, single-centre setting, small sample size, lack of a comparator pathway, and very low event rate preclude conclusions regarding clinical utility, safety, superiority, or outcome benefit. These findings support further prospective evaluation of SPECT high-risk bariatric patients to better define its role within the preoperative cardiac assessment pathway.