射频消融原理解读.ppt

Dr Jackman推荐 在使用冷盐水导管时 功率控制模式,提高消融的效率 安全性同温度控制模式 可以先以较低的预设功率（20W）消融，如电位下降不明显，可再调整至30-35W 消融中应密切注意阻抗变化 冷盐水导管使用建议 Thank You Thank You * * Note: Ablation electrode is heated by the tissue, and not vice versa. Therefore tip temperature will always be lower than tissue temperature. * - As increasing lesion size by delivering higher output power is limited due to safety issues (Pop), different modes of power application might allow for more efficacy while mainting safety in power delivery * Explain power control, play animation by clicking arrow button * Show 25 W application first (select 25W, then press arrow button), then show 60 W application. Note: As lesion size is proportional to energy delivered, one might be tempted to increase power output. Power output however is limited, as tissue overheating can cause steam pops, potentially damaging the tissue severly. * Explain T-control, play animation by clicking arrow button * Point out that comparing Power to Temp. Control mode, T-control is more efficient and safer (which is historically why it‘s been developed) * Point out that comparing Power to Temp. Control mode, T-control is more efficient and safer (which is historically why it‘s been developed) * Besides using different modes of power delivery (P- or T-control), variation of the ablation tip could enhance efficacy of energy delivery, allowing to form bigger lesions * Quizz question: appying constant power, which tip will form the bigger lesion: the bigger 8mm or the smaller 4mm electrode Then play animation Explain current density and cooling effect * However, Cavitary blood flow is not optimal for cooling, because its pulsatile and depending on anatomical location of catheter tip (play animation) * 输出能量不是全部传递到组织，而是部分散失到电极周围的盐水和血液； 贴靠越好能量散失越少，贴靠不良会加大能量的散失； 盐水灌注会增加能量的散失。 * * Note: no correlation of tip to tissue temperature: While electrode stays at 38-43 degrees Celsius, tissue temperature raises to over 107 degrees, causing steam pop. * Active cooling lowers