Gründeman Paul F, Budde Ricardo, Beck Hendricus Mansvelt, van Boven Wim-Jan, Borst Cornelius
Heart Lung Center Utrecht, Department of Cardiology, University Medical Center Utrecht (Rm G02.523), P.O. Box 85500, 3508 GA Utrecht, the Netherlands.
Circulation. 2003 Sep 9;108 Suppl 1:II34-8. doi: 10.1161/01.cir.0000087901.78859.f9.
Closed-chest, off-pump, multivessel CABG requires modified instruments to expose and stabilize posterior and inferior coronary branches. Using three new prototype devices, we explored the feasibility of endoscopic bypass grafting on these branches and assessed cardiac function during cardiac displacement.
Eight pigs (75 to 85 kg) were instrumented for hemodynamics and paced at 80 to 100 bpm. After closure of the sternotomy wound, the Da Vinci endoscope was inserted subxiphoidally. A sternal hook was used to hoist the sternum ventrally by 5 cm. The articulating EndoStarfish cardiac positioner was placed through a trocar (Ø12 mm). The positioner was fixed to the apex using -400 mm Hg suction and the heart was displaced anteriorly to 90 degrees. In 12 other pigs (75 to 85 kg), both internal mammary arteries (IMA) were harvested and the sternal wound was closed. Five trocar ports were placed for instrumentation (Ø12 mm, two in left chest, two in right chest, and one subxiphoidally). For coronary stabilization, a novel deployable EndoOctopus cardiac stabilizer was employed (suction -400 mm Hg). The Da Vinci robot-telemanipulator system was used for endoscopic grafting of the left and right IMA on posterior and inferior branches (16 anastomoses).
When circumflex arteries were fully exposed and accessible for coronary surgery, stroke volume decreased by 18%+/-3 versus baseline (P=0.02) and mean arterial pressure decreased by 27%+/-6 (P=0.001). Additional 10 degrees Trendelenburg head-down positioning normalized stroke volume and arterial pressure. In the displaced heart, obtuse marginal branches (OM) and the ramus descending posterior (RDP) of the right coronary artery became fully exposed with a mean arterial pressure >70 mm Hg during grafting. No accidental detachment occurred. Coronary target motion was restrained to approximately 1x1 mm. In two test cases, five sham distal anastomoses were created (grafts sewn to epicardium, left IMA to OM2 jump to OM3, right IMA to RDP, and composite graft from left IMA jump to diagonal branch). In 10 animals, 16 successfully completed anastomoses to RPD and OM branches of Ø1.75 to 2.5 mm required 25 to 60 minutes each to construct. At sacrifice, all anastomoses were patent.
In the closed-chest pig in Trendelenburg position and during lifting of the sternum, the EndoStarfish and EndoOctopus enabled IMA grafting of posterior and inferior branches on the beating heart without mean arterial pressure dropping below 70 mm Hg.
非体外循环下的闭胸多支冠状动脉旁路移植术（CABG）需要改良器械来暴露和稳定后降支及下壁冠状动脉分支。我们使用三种新型原型设备，探讨了在这些分支上进行内镜下旁路移植术的可行性，并评估了心脏移位过程中的心脏功能。
对8头猪（75至85千克）进行血流动力学监测，并以80至100次/分钟的频率进行起搏。关闭胸骨切开伤口后，经剑突下插入达芬奇内镜。使用胸骨钩将胸骨向前抬起5厘米。通过一个套管针（直径12毫米）置入关节式EndoStarfish心脏定位器。利用-400毫米汞柱的吸力将定位器固定于心尖，使心脏向前移位90度。在另外12头猪（75至85千克）中，游离双侧乳内动脉（IMA）并关闭胸骨伤口。放置5个套管针端口用于器械操作（直径12毫米，左胸2个，右胸2个，剑突下1个）。为稳定冠状动脉，采用一种新型可展开的EndoOctopus心脏稳定器（吸力-400毫米汞柱）。使用达芬奇机器人-远程操作器系统在左、右IMA与后降支及下壁分支上进行内镜下移植（16个吻合口）。
当旋支动脉完全暴露并可进行冠状动脉手术时，与基线相比，每搏量下降了18%±3（P = 0.02），平均动脉压下降了27%±6（P = 0.001）。再采取头低脚高10度体位可使每搏量和动脉压恢复正常。在心脏移位的情况下，钝缘支（OM）和右冠状动脉后降支（RDP）在移植过程中平均动脉压>70毫米汞柱时可完全暴露。未发生意外脱离。冠状动脉靶点运动被限制在约1×1毫米。在两个测试病例中，进行了5个假远端吻合（将移植物缝合于心外膜，左IMA至OM2跳转到OM3，右IMA至RDP，以及左IMA跳转到对角支的复合移植物）。在10只动物中，成功完成了16个与RPD和OM分支的吻合，吻合血管直径为1.75至2.5毫米，每个吻合口构建时间为25至60分钟。处死动物时，所有吻合口均通畅。
在头低脚高位的闭胸猪中，以及在胸骨抬起过程中，EndoStarfish和EndoOctopus能够在跳动的心脏上对后降支及下壁分支进行IMA移植，且平均动脉压不会降至70毫米汞柱以下。
