Successful radiofrequency catheter ablation for electrical storm of ventricular fibrillation in a patient with Brugada syndrome.

The case of a 41-year-old man with Brugada syndrome (BS) who suffered electrical storms (ES) of ventricular fibrillation (VF) is presented. Although intravenous infusion of isoproterenol (ISP) suppressed the VF occurrence, he consistently experienced recurrence of VF following discontinuation of ISP infusion. Quinidine and cilostazol were ineffective. An analysis of VF episodes on electrocardiogram monitoring revealed that the QRS morphology of the first beat of all VF episodes was identical to that of premature ventricular complexes (PVCs) with a left bundle branch-block morphology and inferior axis, which occurred repetitively before the episodes of VF and were recorded throughout the day. In addition, stored electrograms from the implantable cardioverter defibrillator showed that the first beat of all VF episodes had the same morphology. On electrophysiological study, the VF-triggering PVC was found to originate from the posterior portion of the right ventricular outflow tract area and their elimination, which was achieved with radiofrequency catheter ablation (RFCA), resulted in the suppression of ES. Although several other PVCs were still observed, the patient has been free of VF during the 29-month follow-up period. This case indicates that RFCA of VF-triggering PVCs may be useful in the treatment of drug-resistant ES in patients with BS.     

Port-access aortic valve replacement.

A 42-year-old man suffering from massive aortic valve regurgitation with mild stenosis because of a bicuspid valve underwent surgery in May 2007. The surgical procedure was performed through a right anterolateral thoracotomy using the peripheral cannulation method. Cardiac arrest was achieved by direct aortic cross-clamping and selective cardioplegia delivery. The aortic valve was replaced with a bioprosthesis. The operation and aortic cross-clamping periods were 265 and 117 min, respectively. The patient's recovery was uneventful, and he was discharged from hospital 8 days after surgery.     

TNF-alpha induces thromboxane receptor signaling-dependent microcirculatory dysfunction in mouse liver

TNF-alpha is a critical mediator of hepatic microcirculatory dysfunction during endotoxemia. The present study was to investigate the role of thromboxane A2 (TXA2) and the biological significance of thromboxane prostanoid (TP) receptor signaling in TNF-alpha-mediated hepatic microcirculatory dysfunction in male C57Bl/6 mice. The number of leukocytes adhering to the endothelial cells of the hepatic microvessels (the portal venules, sinusoids, and central venules) and the percentage of nonperfused sinusoids were determined using in vivo fluorescence microscopy. FR167653, an inhibitor of TNF-alpha, was administered 0 and 2 h after LPS injection. A TXA2 synthase inhibitor, OKY-046, was administered 30 min before TNF-alpha injection. Thromboxane prostanoid receptor knockout mice were used to investigate whether TNF-alpha-induced hepatic microcirculatory dysfunction is mediated by endogenously produced TXA2. FR167653 reduced LPS-induced leukocyte adhesion (50%-80%) and the percentage of nonperfused sinusoids (55%). The leukocyte adhesion was increased in the portal venules (8-fold), sinusoids (51-fold), and central venules (73-fold) in TNF-alpha-treated mice, accompanied with an increase in sinusoidal perfusion deficits (8-fold). Alanine aminotransferase levels rose as the adhesion of leukocytes increased. OKY-046 administration before TNF-alpha administration reduced leukocyte adhesion (41%-49% decrease) and sinusoid perfusion deficits (34% decrease). In TP receptor knockout mice, the number of adhering leukocytes, the percentage of nonperfused sinusoids, and alanine aminotransferase levels were lower (by 43%-56%, 41%, and 29%, respectively) than in wild-type counterparts. The results suggest that TP receptor signaling may promote hepatic microcirculatory dysfunction elicited by TNF-alpha. Blockade of TNF-alpha generation and TP receptor signaling may be a good strategy for managing endotoxin-induced hepatic injury.     

A new method for evaluation of fracture healing by echo tracking

Assessment of bone healing on radiographs depends on the volume and radio-opacity of callus at the healing site, but is not necessarily objective, and there are differences of judgment among observers. To overcome this disadvantage, a clinical system was developed to quantify the stiffness of healing fractures of the tibia in patients by the echo tracking (ET) method in a manner similar to a three-point bending test. The purpose of this study was to ensure that the ET system could clinically assess the progress, delay or arrest of healing. The fibular head and the lateral malleolus were supported. A 7.5-MHz ultrasound probe was placed on the proximal and distal fragments and a load of 25 N was applied. Five tracking points were set along the long axis of the ultrasound probe at intervals of 10 mm. With a multiple ET system, two probes measured the displacement of five tracking points on each of the proximal and distal fragments of the tibia, thereby detecting the bending of the two fragments generated by the load. ET angle was defined as the sum of the inclinations of the proximal and distal fragments. Eight tibial fractures in seven patients treated by a cast or internal fixation were measured over time. In patients with radiographically normal healing, the bending angle decreased exponentially over time. However, in patients with nonunion, the angle remained the same over time. It was demonstrated that the ET method could be clinically applicable to evaluate fracture healing as a versatile, quantitative and noninvasive technique. (E-mail: ohnishii-dis@h.u-tokyo.ac.jp)     

The Number of Metastatic Lymph Nodes is a Significant Risk Factor for Bone Metastasis and Poor Outcome After Surgery for Linitis Plastica-type Gastric Carcinoma

BACKGROUND: Linitis plastica-type gastric carcinoma remains a disease with poor prognosis despite an aggressive surgical approach. Although a prominent pattern of disease failure is peritoneal carcinomatosis, some patients experience rapid disease progression without signs of the peritoneal disease. METHODS: Clinicopathologic data from 178 patients with linitis plastica-type gastric cancer operated on between 1991 and 2000 were analyzed. Survival stratified by curability of surgery, pN stage, and patterns of failure were evaluated by using the Kaplan-Meier method, and chi(2) test was used to evaluate correlation between the number of metastatic lymph nodes in terms of pN categories and the incidence of various patterns of metastasis and recurrence. Cox regression hazard model was used to identify independent prognostic factors. RESULTS: R0 resection was performed only among 82 patients (46% of those who underwent laparotomy). Node metastasis was frequent with only 22 patients classified as pN0. Peritoneal carcinomatosis was observed in 131 patients and was the commonest pattern of recurrence. Bone metastasis, found in 13 patients, was associated with poor outcome, and its incidence was significantly correlated with the number of metastatic nodes. pT4 status and pN3 status were identified as significant independent prognostic determinants. CONCLUSION: Treatment strategy for the linitis plastica should in general combine surgery with aggressive treatment directed toward peritoneal disease. However, patients with >16 metastatic nodes more often are associated with bone metastasis than those with modest nodal involvement and suffer from poor prognosis.     

Heavily calcified chronic total occlusion of common iliac artery successfully treated with Tornus microcatheter and rotational atherectomy

A 58-year-old man who required long-term hemodialysis was referred to our institution for the management of life-limiting intermittent claudication of the right lower extremity. The diagnostic arteriography demonstrated heavily calcified chronic total occlusion in the right common iliac artery. The lesion was successfully treated with the combination of a Tornus microcatheter (Asahi Intecc, Aichi, Japan) and rotational atherectomy. We describe in this article a niche application of the Tornus microcatheter and the effect of the combination technique of it with rotational atherectomy in peripheral interventions.