RESUMO
[Figure: see text].
Assuntos
Terapia por Exercício , Claudicação Intermitente , Análise Custo-Benefício , Humanos , Claudicação Intermitente/diagnóstico , Claudicação Intermitente/terapia , Qualidade de Vida , Resultado do TratamentoRESUMO
BACKGROUND: Four-dimensional flow magnetic resonance imaging (4D flow MRI) can accurately visualize and quantify flow and provide hemodynamic information such as wall shear stress (WSS). This imaging technique can be used to obtain more insight in the hemodynamic changes during cardiac cycle in the true and false lumen of uncomplicated acute Type B Aortic Dissection (TBAD). Gaining more insight of these forces in the false lumen in uncomplicated TBAD during optimal medical treatment, might result in prediction of adverse outcomes. METHODS: A porcine aorta dissection model with an artificial dissection was positioned in a validated ex-vivo circulatory system with physiological pulsatile flow. 4D flow MR images with 3 set heartrates (HR; 60 bpm, 80 bpm and 100 bpm) were acquired. False lumen volume per cycle (FLV), mean and peak systolic WSS were determined from 4D flow MRI data. For validation, the experiment was repeated with a second porcine aorta dissection model. RESULTS: During both experiments an increase in FLV (initial experiment: ΔFLV = 2.05 ml, p < 0.001, repeated experiment: ΔFLV = 1.08 ml, p = 0.005) and peak WSS (initial experiment: ΔWSS = 1.2 Pa, p = 0.004, repeated experiment: ΔWSS = 1.79 Pa, p = 0.016) was observed when HR increased from 60 to 80 bpm. Raising the HR from 80 to 100 bpm, no significant increase in FLV (p = 0.073, p = 0.139) was seen during both experiments. The false lumen mean WSS increased significant during initial (2.71 to 3.85 Pa; p = 0.013) and non-significant during repeated experiment (3.22 to 4.00 Pa; p = 0.320). CONCLUSION: 4D flow MRI provides insight into hemodynamic dimensions including WSS. Our ex-vivo experiments showed that an increase in HR from 60 to 80 bpm resulted in a significant increase of FLV and WSS of the false lumen. We suggest that strict heart rate control is of major importance to reduce the mean and peak WSS in uncomplicated acute TBAD. Because of the limitations of an ex-vivo study, 4D flow MRI will have to be performed in clinical setting to determine whether this imaging model would be of value to predict the course of uncomplicated TBAD.
Assuntos
Aorta/diagnóstico por imagem , Aneurisma Aórtico/diagnóstico por imagem , Dissecção Aórtica/diagnóstico por imagem , Hemodinâmica , Imageamento por Ressonância Magnética , Imagem de Perfusão , Dissecção Aórtica/fisiopatologia , Animais , Aorta/fisiopatologia , Aneurisma Aórtico/fisiopatologia , Velocidade do Fluxo Sanguíneo , Modelos Animais de Doenças , Frequência Cardíaca , Valor Preditivo dos Testes , Fluxo Sanguíneo Regional , Estresse Mecânico , Sus scrofa , Fatores de TempoRESUMO
PURPOSE: Drug-eluting stents (DES) improve clinical and morphological long-term results compared to percutaneous transluminal angioplasty (PTA) with bailout bare metal stenting (BMS) in patients with critical limb ischemia (CLI) and infrapopliteal lesions (PADI trial). We performed a cost-effectiveness analysis of DES compared to PTA ± BMS in cooperation with Dutch health insurance company VGZ, using data from the PADI trial. MATERIALS AND METHODS: In the PADI trial, adults with CLI (Rutherford category ≥ 4) and infrapopliteal lesions were randomized to receive DES with paclitaxel or PTA ± BMS. Seventy-four limbs (73 patients) were treated with DES and 66 limbs (64 patients) with PTA ± BMS. The costs were calculated by using the mean costs per stent multiplied by the mean number of stents used per patient (750 × 1.8 for DES vs 250 × 0.3 for PTA ± BMS). These costs were compared with the costs of major amputation (16.000) and rehabilitation (first year 15.750, second year 7.375 and third year 3.600). RESULTS: The 5-year major amputation rate was lower in the DES group (19.3% vs 34.0% for PTA ± BMS; p = 0.091). In addition, the 5-year amputation-free survival and event-free survival were significantly higher in the DES group (31.8% vs 20.4%, p=0.043; and 26.2% vs 15.3%, p=0.041, respectively). After 1 year, the cost difference per patient between DES and PTA ± BMS is 1.679 in favor of DES and 2.694 after 3 years. CONCLUSION: In our analysis, DES are cost-effective due to the higher hospital costs of amputation and rehabilitation in the PTA ± BMS group. LEVEL OF EVIDENCE: Level 1b, analysis based on clinically sensible costs and randomized controlled trial.