Cardiac magnetic resonance findings predict increased resource utilisation in elective coronary artery bypass surgery

Colin Berry (1) , Lukas U Zimmerli , Tracey Steedman , John E Foster , Henry J Dargie , Geoffrey A Berg , Anna F Dominiczak , Christian Delles

1 BHF GCRC - Glasgow Cardiovascular Research Centre

Background: Morbidity following coronary artery bypass graft (CABG) surgery is difficult to predict and leads to increased healthcare costs. We hypothesised that pre-operative cardiac magnetic resonance (CMR) findings would predict resource utilisation in elective CABG. Methods: Over a 12-month period, elective CABG patients were invited to undergo CMR one day prior to CABG. Gadolinium-enhanced CMR was performed using a trueFISP inversion recovery sequence on 1.5 tesla scanner (Sonata, Siemens). Clinical data were prospectively collected. Admission costs were quantified based on standardised actual cost-per-day. Admission cost > median was defined as "increased". Results: Of 458 elective CABG cases, 45 (10%) underwent pre-operative CMR. Pre-operative characteristics (mean (standard deviation) age 64 (9) years), mortality (1%) and admission duration (median (interquartile range 7 (6, 8) days) were similar in patients who did or did not undergo CMR. In the CMR patients, eight (18%) and 11 (24%) patients had reduced left ventricular (LV) systolic function by CMR (LVEF<55%) and echocardiography, respectively. Late enhancement (LE) with gadolinium was detected in 17 (38%) patients. The average cost-per-day was $2,723. The median (range) admission cost was $19,059 ($10,891 to $157,917). CMR LVEF (OR [95$CI] 0.93 [0.87 to 0.99]; p=0.03) and stroke volume index (1.07 (1.00 to 1.14); p=0.02) predicted increased admission cost. CMR LVEF (p=0.08) and EuroScore tended to predict actual admission cost (p=0.09), but SV by CMR (p=0.16) and LV function by echocardiography (p=0.95) did not. Discussion: In this exploratory investigation, preoperative CMR findings predicted admission duration and increased admission cost in elective CABG. The cost-effectiveness of CMR for risk stratification in elective CABG merits prospective assessment.

Mots clés: Medicine

Colin Berry, Lukas U Zimmerli, Tracey Steedman, John E Foster, Henry J Dargie, et al.. Cardiac magnetic resonance findings predict increased resource utilisation in elective coronary artery bypass surgery. Clinical Science, 2007, 114 (6), pp.423-430. ⟨10.1042/CS20070337⟩. ⟨hal-00479404⟩