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Map-guided surgery is the goal for treatment of atrial fibrillation (AF), because it minimizes unnecessary incisions or procedures. We propose a totally-noninvasive and even non-contact method to detect atrial arrhythmia with a superconducting quantum interference device magnetocardiography (MCG) system, and report the first clinical application case of MCG map-guided AF surgery. To detect weak atrial excitation, we utilized a high sensitive 64-channel MCG system measuring tangential magnetic field components, which is known to be more sensitive to a deeper current source. We measured the MCG signals from eight patients with chronic AF. Then, we separated the f-wave from the other components by using independent component analysis. The extracted f-wave caused by reentrant myocardial excitation was three-dimensionally localized on the mesh model of a human heart by a novel beamformer technique having a surface action potential activity as its filter output. We localized the abnormal stimulation source of an atrial arrhythmia non-invasively and visualized the current source distribution corresponding to the atrial excitation successfully on the three-dimensional atrial surface, which was separated from the ventricular excitation. Using this atrial mapping, we underwent minimal AF surgery in three patients and converted their AF to sinus rhythm successfully.

Postero-lateral thoracotomy has many complications such as postoperative pain, limitation in the motion of the shoulder, decreasing pulmonary function from immobilization, increasing lung atelectasis from over-use of analgesia, and increasing pulmonary morbidity, especially in elderly patients. So, muscle-sparing thoracotomy appears to be a good alternative. But it has also many disadvantages such as seroma and the needs for drains, limitation of an accessible operative field, and difficulties with risky procedures. We have modified muscle-sparing vertical thoracotomy. We performed 134 procedures on 131 patients from October 2000 to September 2003, including 15 cases of esophageal cancer, 95 cases of lung cancer, and 24 cases of other disease. Operative procedures were lobectomy in 74 cases, bilobectomy in 12 cases, pneumonectomy in 10 cases, wedge resection in 8 cases, decortication in 2 cases, Ivor Lewis procedure in 13 cases, and others in 15 cases. There was no occurrence of wound infection, arrrhythmia, fibrillation, and subcutaneous seroma except the first two cases. We had seven reoperations (two postoperative bleeding, three postpoperative BPF, one EGstomy leak, one RML torsion) and four operative mortalities (one postpneumonectomy BPF, two pneumonia, one heart failure). Our muscle-sparing vertical thoracotomy can be done safely in most thoracic surgery including lung and esophageal cancer, therefore it is a feasible procedure.

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Carotid endarterectomy (CEA) influences the carotid endoluminal anatomy, which results in hemodynamic changes before and after surgery. We investigated the hemodynamics of severe carotid artery stenosis before and after conventional endarterectomy with/without patch repair. An in vitro experiment utilizing carotid phantoms, which underwent a procedure that emulated CEA with/without the patch repair, was performed with a high-spatiotemporal resolution using 4D flow MRI. We evaluated an abnormal region of carotids, which consists of the normalized time-averaged wall shear stress (NTA|WSS|) and the oscillatory shear index (OSI), to account for continuous high-shear regions (high NTA|WSS| and low OSI) and chaotic low-shear regions, i.e., stenosis-prone regions (low NTA|WSS| and high OSI). The use of normalized hemodynamic parameters (e.g., NTA|WSS|) allowed comparison of diverse cases with different conditions of hemodynamics and vessel geometry. We observed that the stenosis-prone regions of the carotids with patches were noticeably larger than the corresponding regions in no-patch carotids. A large recirculating flow zone found in the stenosis-prone region of the internal carotid artery (ICA) of the postoperative carotids with patches partially blocks the flow path into ICA, and consequently the flow rate was not recovered after surgery unlike an expectation.

The present research investigated the role of blood viscosity on flow within a microvascular network to identify the conditions of blood flow stagnation. When the yield stress of blood was less than 0.005 Pa, there were no stagnant regions in the microvasculature. However, when the yield stress increased to 0.05 Pa, stagnant or reduced flow areas began to appear, which grew and expanded rapidly with further increase in the yield stress. Thus, the yield stress determined from blood viscosity profile of a patient can be utilized to evaluate the risk of circulatory impairment.

Background: Superior sulcus (Pancoast) tumors are preferably treated with neoadjuvant chemoradiotherapy and surgical resection. Induction chemoradiation increases the probability of a complete resection and local control, but is associated with an increased complication rate after surgery. Comorbidity, pulmonary reserve and response to induction treatment determine whether this demanding trimodality treatment can be advocated. Resections generally involve the upper lobe with contiguous thoracic wall including apical ribs (and T1 plexus root /partial vertebra if necessary), but even more extensive resections have been performed in fit patients. We evaluated the role of surgery as part of multimodality treatment in our institute. Methods: From registration databases all patients with Pancoast tumors, referred to our institute between 1995 and 2006, were identified. All patients without distant metastasis were selected for treatment with curative intent. The preferred treatment consisted of chemoradiation (66 Gy radiotherapy in fractions of 2,75 Gy with daily cisplatinum 6 mg/m 2 ) followed by resection. Presenting symptoms, performance status, pulmonary function, clinical and pathological tumor stage, (response to) treatment, and survival were reviewed retrospectively. Survival analysis was performed using the Kaplan-Meier method. Results: From 1995 to 2006, 85 patients with Pancoast tumors, 57 men and 28 women, were referred to our institute. The median follow-up was 15 months (2-123). Mean age was 57 years (32-82). After additional diagnostic staging, 25 patients had stage IIB (29%), 7 stage IIIA (8%), 32 stage IIIB (38%) and 21 stage IV (25%). Of those patients presenting with stage II or III disease, 22 underwent a resection after induction treatment. The 2-and 5-years overall survival was 70% and 37%, respectively. All these resections were complete and local recurrences were not observed. In 13 out of 22 patients a pathologic complete tumor response (pCR) was found after induction treatment. pCR was a significant prognostic factor for survival (5 year survival of 50% vs. 17%). In most cases, pathologic response was not evident from radiologic imaging (restaging with CT or MRI). The morbidity of surgery after induction treatment was acceptable: 6 pneumonias, 1 tracheoesophageal fistula, 1 chylothorax, 1 complete atelectasis, 1 postoperative bleeding. There were no fatal toxicities or treatment-related mortalities. Forty-two patients were rejected for resection due to comorbidity/inoperability (n=25), irresectability or insufficient response on induction treatment. Nineteen of these patients received concurrent chemoradiation (2-and 5-year survival 39% resp. 15%) and 23 patients were treated with radiotherapy, chemotherapy or both sequentially (2-and 5-year survival 18% resp. 5%). Local recurrence/progression occurred in 13 out of 42 patients, six of these patients had distant metastases as well. Conclusions: Surgical resection following induction chemoradiation is associated with excellent local control and ac...