A ventricular assist device powered by conditioned skeletal muscle.

BACKGROUND: We are developing and testing a new ventricular assist device (VAD) to be powered by conditioned skeletal muscle. METHODS: To evaluate the VAD hardware and to develop a muscle training regimen, 8 calves have been used in studies in which the right latissimus dorsi muscle was employed. The experiments were carried out to an approximately 4-month duration. RESULTS: There was significant conversion of type II (fast twitch) to type I (slow twitch) muscle fibers. This did not correlate well, however, with device performance. The device stroke volumes ranged from approximately 17 to 90 cc. This variability of outcome occurred despite the fact that identical hardware, surgical procedures, and training regimens were employed. CONCLUSIONS: The results from the first eight studies lead us to speculate that perfusion may be important even when the muscle is working at pressures much lower than systemic blood pressure levels. In an attempt to augment tissue perfusion, we plan to investigate thermally induced angiogenesis as a possible mechanism for increasing blood flow to the tissue.

Fatal paradoxic embolism occurring during IVC filter insertion in a patient with chronic pulmonary thromboembolic disease.

A patient diagnosed with chronic thromboembolic disease experienced a fatal intraprocedural paradoxic embolism during inferior vena cava (IVC) filter insertion. The frequency of patent intra-atrial shunts in patients with chronic thromboembolic disease is surprisingly high, occurring in approximately 29.5% of patients with chronic thromboembolic disease. Prevention of embolic events during venous interventions in such cases requires that the operator recognize that central shunts may be present and strictly adhere to meticulous technique during IVC filter insertion.

Reoperation of Recurrent Gastric Cancer.

PURPOSE: The aim of this study was to evaluate the outcome of reoperation in recurrent gastric cancers. MATERIALS AND METHODS: We conducted a retrospective analysis of 86 patients who underwent reoperation for recurrent gastric cancer. We reviewed the time interval between first operation and reoperation, as well as the recurrence pattern, type of reoperation, and survival following reoperation. RESULTS: the average time to reoperation following curative resection was 27.8+/-25.9 months (median 18.4 months). Fifty-three cases (61.6%) of reoperation were performed within 2 years follwoing the first operation. The most common reason for reoperation was intestinal obstruction followed by gastric remnant recurrence and intra-abdominal mass. Complete resection was possible in 14 cases (16.3%) and a palliative procedure such as partial resection or bypass procedures was performed in 54 cases. In 18 cases (20.9%), simple lapalotomy was done without any aid. The most common site of recurrence was the peritoneum followed by the gastric remnant, distant lymph node and hematogenous liver metastasis. Operative mortality was 10.5%. Excluding the 9 cases of operative mortality, the mean survival time after reoperation was 15.4+/-2.5 months (mean 8.6 months). Survival following complete resection was much longer than palliative procedure and exploration only (37.9+/-8.7 vs 10.9+/-1.5 vs 4.7+/-0.8 months, p=0.000). CONCLUSION: The complete resection of recurrent gastric cancer can prolong survival. Early detection of localized recurrence is important in order to increase the chance of complete resection.