Masaki Nie

Electromagnetic Interference of Implantable Unipolar Cardiac Pacemakers by an Induction Oven

Induction ovens have been reported to exert electromagnetic interference on implanted cardiac pacemakers. In an attempt to quantitatively investigate the electromagnetic interference caused by an induction oven on implantable unipolar cardiac pacemakers, we measured the distribution profile of the magnetic field intensity, both with and without a pan on the induction oven. We also performed the inhibition test and asynchronous test using four kinds of pacemakers housed in the standardized Irnich human body model, and measured the maximal distance from the induction oven up to which the interference occurred. In the pan‐detection mode of the oven in the absence of a pan, the distribution profile of the magnetic field intensity peaked at the center of the cooking plate, and during induction heating of a pan placed on the induction oven, it was the largest at the circular top‐edge of the pan. Pacemaker pulses were inhibited by the induction oven, or generated by the reversion mechanism. The maximal interference distance from the oven was 34 cm for one of the pacemakers. Thus, the safe distance from an induction oven of a patient with an implanted cardiac pacemaker is considered to be 50 cm or more. In conclusion, in the pan‐detection mode of the oven in the absence of a pan, the distribution profile of the magnetic field intensity peaked at the center of the cooking plate, and during the induction heating of a pan placed on the oven, it peaked at the circular edge of the pan. The induction oven asynchronized or generated pulses in implantable unipolar cardiac pacemakers up to a maximal distance of 34 cm from the induction oven.

Double-patch closure using gelatin resorcine formol glue of a ventricular septal perforation following acute myocardial infarction.

Complete closure is most important when attempting acute-phase closure of a ventricular septal perforation following acute myocardial infarction. Here, we present a case of a 76-year-old male with a ventricular septal perforation following acute myocardial infarction. The ventricular septal perforation was repaired by stitching small and large bovine pericardial patches onto the affected septum from the side of the left ventricle, then cementing the two patches together with gelatin resorcine formol glue injected into the space between them. Complete closure of the ventricular septal perforation was accomplished. Simultaneously, right coronary artery bypass grafting was performed using a saphenous vein. The postoperative course was uneventful, and the patient was discharged, with a favorable post-discharge course for 24 months to date after surgery.

For what type of constrictive pericarditis is the waffle procedure effective

The waffle procedure is performed in patients with marked thickening and calcification of the epicardium and no substantial improvement in hemodynamic parameters after pericardiectomy. We retrospectively investigated the efficacy of the waffle procedure in 6 of 11 patients who underwent pericardiectomy. These 6 patients showed no improvement in central venous pressure, pulmonary arterial pressure, pulmonary capillary wedge pressure, or cardiac index after pericardiectomy. After the waffle procedure, all hemodynamic parameters improved, and there were no significant differences compared to those of the 5 patients who did not require the waffle procedure, despite higher pulmonary capillary wedge pressure and lower cardiac index values preoperatively in the waffle group. The waffle procedure was considered effective in patients with persistent epicardial constriction.

Ulnar artery graft for myocardial revascularization.

We present a 60-year-old man who underwent coronary artery bypass grafting using an ulnar artery as one of the grafts intended to release angina pectoris. Previously, his right leg had been amputated following a traffic accident. The blood supply of his left leg was reduced due to atherosclerotic stenotic change (left ankle pressure index 0.6). He had been under treatment for severe diabetes mellitus for 4 years. Coronary angiography revealed severe stenosis in the triple coronary artery system. Immediate myocardial revascularization was considered necessary. We considered that saphenous vein grafts and bilateral internal thoracic artery grafts were unsuitable for this patient. Moreover, Allens test was positive in the bilateral forearms. Coronary artery bypass surgery consisted of left internal thoracic artery grafting to the left anterior descending artery, right gastroepiploic artery grafting to the right coronary artery, and left ulnar artery grafting to the diagonal branch. No myocardial or hand complications were observed after surgery. Following a review of the Japanese literature, we conclude that our case is the first report of an ulnar artery graft for coronary artery bypass grafting in Japan.

Protection of the spinal cord with pentobarbital and hypothermia

BACKGROUND Ischemic spinal cord damage during thoracic aortic operations has not been eliminated despite application of various adjuncts. We experimentally investigated the protective effects of pentobarbital and hypothermia on the spinal cord subjected to ischemia. METHODS Among nine groups of 6 rabbits each, groups AI to AIII underwent 20-minute infrarenal aortic occlusion, and groups BI to BVI underwent 40-minute occlusion. Five milligrams per kilogram of pentobarbital was administered to groups AII and BII; 10 mg/kg in groups AIII, BIII, and BVI; 20 mg/kg in group BIV; and none in groups AI, BI, and BV. In groups BV and BVI, hypothermia was induced. Forty-eight hours postoperatively, the motor function of the lower limbs was evaluated. RESULTS Statistically significant recovery of motor function was observed in animals in groups AII, AIII, BIII, BIV, BV, and BVI. CONCLUSIONS Pentobarbital showed dose-dependent protective effects of the spinal cord. Moderate hypothermia alone also showed protective effects. Combined use of pentobarbital and hypothermia resulted in highly significant recovery of spinal cord function.

Death due to undetected heparin-induced thrombocytopenia after cardiac surgery.

A 41-year-old male patient was diagnosed acute myocardial infarction. An intra-aortic balloon pump was inserted to treat heart failure, and off-pump coronary artery bypass surgery was performed. Postoperative cardiac catheterization revealed occlusion of all the 3 bypass grafts, and percutaneous coronary intervention (PCI) was performed. Thrombosis due to heparin-induced thrombocytopenia (HIT) occurred during PCI, which was completed after switching to argatroban based on the possible HIT. Cardiopulmonary arrest occurred suddenly after PCI, and the patient died. Undetected HIT may have caused the sudden change. HIT should be suspected and aggressively treated when thrombocytopenia occurs even during assisted circulation.

Repair of Ventricular Septal Perforation after Inferior Myocardial Infarction

Various techniques have been used for repair of ventricular septal perforation complicating inferior myocardial infarction, but no standard method has been established. An effective technique for closing ventricular septal perforation using double patches via a right atrial approach is described. In our experience, no residual shunt was observed after repair using this procedure.

Surgical management of left ventricular thrombus following severe dehydration.

We experienced a case involving a left ventricular ball-like thrombus caused by severe following a 150 mile cycling road race. The patient had lower-limb arterial obstruction due to systemic thromboembolism on admission with no significant embolism, including the cerebral arteries, were detected. Left ventricular wall motion was good with no evidence of left and right coronary artery occlusion; therefore, we performed emergency left ventricular thrombectomy. Although there are many reports of left ventricular thrombus following acute myocardial infarction, dehydration is a very rare cause. Herein, we describe the surgical and management approaches to the treatment of left ventricular thrombectomy in this case.