Abstract 20527: Aortic Valve Patient-Prosthesis Mismatch in Obesity: Is it Time to Reconsider?
Introduction: Prosthesis-patient mismatch (PPM) results in high gradients and adverse patient outcomes. The effective orifice area (EOA) index (EOAi), dividing EOA by body surface area (BSA), is frequently employed to classify PPM severity. But this approach can disagree other metrics, especially for obese patients.
Hypothesis: We hypothesize that indexing EOA by substituting fat-free mass (FFM) for weight could reduce the degree of PPM for small aortic valves.
Methods: We substituted FFM, calculated by a validated bi-exponential algorithm, for weight in the Mosteller BSA formula (BSAFFM) to derive an EOA indexed to BSAFFM (EOAiFFM). We compared EOAi vs EOAiFFM for reported EOA reference values 19 (1.1 cm2), 21 (1.3 cm2), and 23 mm (1.3 cm2) model 2700 Edwards Perimount pericardial valves each implanted in 65 men (M) and 65 females (F) whose heights and weights approximated values reported by the CDC for all racial and ethnic groups ≥20 years. Severe, moderate, and no PPM were defined as EOAi ≤0.65 cm2/m2, 0.65 cm2/m2 < EOAi ≤ 0.85 cm2/m2, and >0.85 cm2/m2 respectively.
Results: Mean BMI did not differ between M (32.7 ± 9.0 kg/m2) and F (30.0 ± 9.6 kg/m2) (P=NS). Obesity (BMI ≥30 kg/m2) occurred more frequently in M (58.5%) than F (44.6%). BSA (2.22 ± 0.35 m2 vs 1.87 ± 0.32 m2, P <.001), FFM (64.8 ± 10.1 kg vs 45.9 ± 6.6 kg, P <.001), and BSAFFM, (1.78 ± 0.19 m2 vs 1.44 ± 0.14 m2, P <.001) were greater in M than F. Obese patients had a higher prevalence of severe PPM (M: 88.6%; F: 69.0%) vs non-obese (M: 44.4%; F: 14.8%), the prevalence of severe PPM declined more in obese (M: 55.3% ; F: 66.7%) than non-obese (M: 25.9%; F: 14.8%) with EOAiFFM. As shown in the Table, EOAiFFM reduced severe PPM more in obese females than obese males for 19 and 21 mm valves.
Conclusions: 1. Obese patients with aortic pericardial valves have a higher percent of severe PPM than non-obese patients. 2. Indexing EOA to BSAFFM appears reduce severe PPM more in obese patients, an effect noted especially in women with 19 and 21 mm valves.
Author Disclosures: A.K. Gupta: None. J.A. Strom: None.
- © 2016 by American Heart Association, Inc.