TCT2006 alcohol septal ablation
author/presenter is John Buergler
Three Month Results Using a Novel Magnetic Navigation System to Perform Alcohol Septal Ablation
Background: Some patients with hypertrophic obstructive cardiomyopathy (HOCM) develop medically-refractory angina and heart failure that can be debilitating. Alcohol septal ablation (ASA) has been used to improve these symptoms, although septal perforator cannulation can be challenging given its takeoff from the LAD and/or small size. A new device that assists with ASA is magnetic assistance ((Stereotaxis, Inc. St. Louis, MO), in which magnetic fields are used to guide the wire tip to the desired location. However, little clinical and echo follow-up data exist in patients who have ASA using MAI. We assessed improvements in symptoms, exercise capacity and echo parameters symptoms at 3 months.
Methods: From October 2004 through December 2005, twenty-nine consecutive HOCM patients with medically-refractory symptoms of angina underwent ASA using magnetic assistance with the Niobe System (Stereotaxis, Inc. St. Louis, MO). These patients were then followed for 3 months to assess changes in CHF, angina, exercise capacity (METS and MV02), echo gradient and septal thickness compared with baseline.
Results: NYHA class improved from 3.2 ± 0.4 to 1.5 ± 0.9 (p<0.001). Angina class improved from 1.9 ± 1.0 to 1.2 ± 0.5 (p<0.01). The pressure gradient was reduced from 70 ± 33 to 32 ± 32 mm Hg (p<0.001). The septal thickness was reduced from 1.9 ± 0.3 to 1.4 ± 0.4 mm (p<0.001). Modified Bruce protocol treadmill time improved from 7.2 ± 4.1 to 9.8 ± 4.3 minutes (p<0.001). MV02 improved from 14.6 ± 4.0 to 17.8 ± 2.7 ml/kg/min (p<0.001).
Conclusions: ASA with MAI provides dramatic reductions in symptoms, exercise tolerance, echo gradient and septal thickness at 3 months. MAI has the potential to increase the efficacy of ASA in patients with HOCM. Additional studies are warranted to prove this hypothesis.
TCT2006 robotic epicardial ablation
author is Takeyoshi Ota.
Epicardial Atrial Ablation Using A Novel Highly Articulated Robotic Probe Through A Subxiphoid Approach.
Background: Minimally invasive epicardial atrial ablation to cure atrial fibrillation using a percutaneous subxiphoid approach is currently hampered by the lack of dedicated technology for intrapericardial navigation around the beating heart. We have developed second prototype of a novel highly articulated robotic probe and performed experiments in a porcine preparation.
Methods: The highly articulated robotic probe consists of the feeder and the rod looks like a “snake”. The “snake” robot is aimed to facilitate to access to intraepicardial space with a small skin incision and deliver therapeutic instruments through the working port of the robot.
In 5 large healthy pigs, the robotic catheter was introduced inside the pericardial space using a subxiphoid percutaneous approach in a closed chest environment and tested navigation to the left atrial appendage through some pathways, while the test was observed using a thoracoscope inserted from the left intercostal space as visualization. The operator actively controlled the path of the catheter using a master manipulator. After the robot with a radiofrequency ablation catheter was guided around the left atrium, epicardial ablation around the pulmonary veins was performed.
Results: Access to the pericardial space and progression around the left atrium was successful in all cases without adverse events. Epicardial ablation was successfully accomplished in all cases. Transmural ablation was confirmed by histopathology of the left atrium.
Conclusions: The second prototype of the snake robot could advance through the pericardial space without adverse events on the closed chest beating heart. We successfully performed epicardial left atrial radiofrequency ablation through the subxiphoid approach. |
