Takanori Oka

Three-dimensional recovery time dispersion map by 64-channel magnetocardiography may demonstrate the location of a myocardial injury and heterogeneity of repolarization.

BackgroundQT dispersion reveals heterogeneities in the repolarization time in the three-dimensional (3D) structure of the ventricular myocardium. In this study, we report on a 3D function map of recovery time (RT) dispersions as measured by 64-channel magnetocardiography (MCG).MethodsMCG were simultaneously recorded in 29 controls and 21 patients with previous myocardial infarction (MI). The 3D current density was calculated from 64-channel MCG data in the Bz component using a space filter. The heart outline, reconstructed from the integrated the current density, revealed both the atrium and ventricle. The RT for the intervals between QRS onset and the time of the maximum dT/dt of T wave, and the peak to the end of the T wave (Tpeak-negative dT/dt) were automatically measured by means of a computer from 3D MCG data. The corrected RT (RTc) and corrected Tpeak-negative dT/dt were then calculated using Bazett’s formula. The 3D RTc and the corrected Tpeak-negative dT/dt dispersion map were superimposed on the heart outline generated by MCG.ResultsThe RTc was significantly longer for the MI group than in the control group (67±25xa0ms1/2 vs. 16±6xa0ms1/2) (p<0.0001). The corrected Tpeak-negative dT/dt dispersions in each patient was also significantly longer for the MI group than in the control group (35±27xa0ms1/2 vs. 10±5xa0ms1/2) (p<0.0001). Furthermore, the 3D RTc and Tpeak-negative dT/dt dispersion maps corresponded with the space location of MI, as defined by Tc-99m tetrofosmin myocardial imagingConclusions3D RTc and Tpeak-negative dT/dt dispersion maps in the ST segment, obtained by 64-channel MCG may be used demonstrate the location of a myocardial injury and heterogeneities of repolarization.

Ethnic differences in the VKORC1 gene polymorphism and an association with warfarin dosage requirements in cardiovascular surgery patients.

OBJECTIVESnVitamin K epoxide reductase (VKORC1) is the drug target for inhibition by coumarin-based anticoagulant drugs such as warfarin. Warfarin therapy has been reported as a leading cause of drug-related hospitalization and there is therefore an urgent need to develop tests for better warfarin prescription. We report here the distribution of the intron 1 -136 T>C (1173 T>C intron) polymorphism of VKORC1, previously reported to be associated with warfarin maintenance dose in Caucasians and Japanese, in several ethnic populations from Japan and Israel, and describe its significance for warfarin dosage in Japanese cardiovascular surgery patients.nnnMETHODSnSubjects consisted of 132 Japanese individuals and 341 Israeli individuals from four Jewish ethnic groups (86 Ashkenazi Jews, 95 Yemenite Jews, 73 Moroccan Jews and 87 Libyan Jews). In addition, 31 Japanese patients receiving warfarin therapy after cardiovascular surgery, maintained with a target International Normalized Ratio, were studied. The genotyping for the 1173 T>C intron polymorphism of VKORC1 was determined using rapid real-time PCR.nnnRESULTSnThe allele frequency of the combined VKORC1 1173 CT and CC genotypes varied among the four Israeli ethnic groups and was, on average, much higher in the Israeli (0.728) than in the Japanese population (0.152). For the Japanese cardiovascular surgery patients, the maintenance dose of warfarin was significantly larger in the combined VKORC1 1173 TC and CC genotype group than in the 1173 TT genotype group (3.6 +/- 0.5 mg vs 2.8 +/- 0.7 mg, respectively; p = 0.02).nnnCONCLUSIONnThe frequencies of the intron 1 VKORC1 1173 T>C SNP show significant differences between ethnic groups and are associated with warfarin dose requirements for achieving a recommended International Normalized Ratio range in Japanese cardiovascular surgery patients. This study supports the example of warfarin as an appropriate model for applying personalized medicine for anticoagulant drugs, and highlights the importance of ethnicity in pharmacogenetics.

Right heart failure caused by direct pressure of distal arch aneurysm

We report a rare case of right heart failure caused by distal aortic aneurysm. Although aortopulmonary fistula is a common complication of giant aortic arch aneurysm, right heart failure caused by mechanical pressure by aneurysm is very rare. A 79-year-old female patient presented dyspnea. Contrast computed tomography (CT) of the thorax delineated a 78xa0mm aortic arch aneurysm pressing the main to left pulmonary artery and a 40xa0mm pericardial effusion at maximum depth at posterior side. Echocardiography showed the acceleration flow from main to left pulmonary artery and moderate pulmonary hypertension. Left ventricular function, however, was preserved. We diagnosed right heart failure caused by giant aortic arch aneurysm and performed emergency aortic arch aneurysm replacement. After the operation, pulmonary artery pressure decreased and right heart failure improved.

Long-Term Results of Crossover Bypass for Iliac Atherosclerotic Lesions in the Era of Endovascular Treatment: The Re-ACTION Study ( Re trospective A ssessment of C rossover Bypass as a T reatment for I liac Lesi ON s)

Objective: The aim of this study was to elucidate the long-term results of crossover bypass (CB) for iliac atherosclerotic lesions in the era of endovascular treatment (EVT). Methods: A retrospective multicenter cohort study was performed. CB was performed in 242 patients between 2003 and 2014 by vascular surgeons at multiple medical centers in Japan. Results: Perioperative mortality was 1.7%. Primary patency rates were 86% at 5 years and 82% at 8 years. Univariate analysis showed that critical limb ischemia (Rutherford class 4–6), vein graft, and superficial femoral artery occlusion were significantly associated with low primary patency. In multivariate analysis, only critical limb ischemia influenced primary patency. The secondary patency rate was 87% at both 5 and 8 years. The limb salvage rate was 98% at both 5 and 8 years. The overall survival rates were 71% at 5 years and 49% at 8 years. Conclusion: The long-term results of CB were good in our study, compared with previous reports. Our results suggest that CB remains an option for the arterial reconstruction in unilateral iliac occlusive disease after EVT failed.

A Case of Tetralogy of Fallot with Endocardial Cushion Defect of the Intact Primary Septum.

症例は1歳3ヵ月,女児,Down症候群.生後1日目に心雑音を指摘され,心エコー上,Fallot四徴症(TOF),僧帽弁閉鎖不全症(MR)と診断されていた.心不全,チアノーゼを認めず経過観察されていたが,乳児期後半より体重増加が不良で,1歳頃よりMRの増悪による心不全のため外科治療目的で当センターに入院した.術中所見では心房中隔欠損はなく,流入部より膜様部を越え漏斗部へ前方進展する心室中隔欠損を認め,房室弁は同一平面上にあり,心室中隔流入部はscoopingしていた.術中所見より一次孔欠損のない心内膜床欠損症(ECD)とTOFの合併例と診断した.経右房肺動脈的に心内を修復し,術後17病日に合併症なく退院した.一次孔欠損のないECDとTOFの合併例はきわめて希であり,若干の文献的考察を加えて報告する.

Bypass graft material and myocardial protective procedure in combined coronary artery bypass grafting and valve surgery

OBJECTIVEnThe aortic cross clamping time is prone to be longer when coronary artery bypass grafting (CABG) is combined with valve surgery. Therefore, the myocardium that is revascularized by in-situ internal thoracic artery graft is at risk to ischemia, and, myocardial protection is especially important in such operation. In this study, the effect of myocardial preservation of combined antegrade, retrograde and terminal warm blood cardioplegia during combined valve surgery and CABG using the internal thoracic artery as a bypass conduit was evaluated.nnnMETHODSnFrom November 1992 to August 1999, 15 patients received combined CABG and valve surgery. Among these 15 patients, 13 patients who did not need hemodialysis were divided into 2 groups, and a comparative study was done. In Group I (n = 5), only the saphenous vein graft was employed for combined CABG and valve surgery, and myocardial protection was done by combined antegrade and terminal warm blood cardioplegia. In Group II (n = 8), at least 1 in-situ internal thoracic artery graft was employed for CABG and valve surgery, and myocardial protection was done by combined antegrade, retrograde and terminal warm blood cardioplegia.nnnRESULTSnDespite longer aortic cross clamping time in Group II, the peak creatine kinase-MB of Group II was significantly lower. In addition, the postoperative administration of dopamine tended to be less in Group II.nnnCONCLUSIONnMyocardial protection by combined antegrade, retrograde and terminal warm blood cardioplegia may be an effective adjunct to combined valve surgery and CABG employing the in-situ internal thoracic artery graft.

Surgical treatment for a supra sinotubular junctional saccular aneurysm associated with aortic regurgitation.

We reported a patient with a saccular ascending aortic aneurysm located just above the non-coronary sinotubular junction. The aneurysm produced severe aortic regurgitation and two episodes of cardiac tamponade. By intraoperative inspection, the border between the aneurysmal wall and non-dilated portion of the normal aortic wall was distinct, and the aortic valve leaflets and aortic annulus appeared normal. Aortic valve dysfunction appeared to be caused by dilation of the noncoronary sinotubular junction and mild distortion of the noncoronary sinus because of the aneurysmal formation. We performed patch closure of the aneurysmal ostium and repaired the dilated noncoronary sinotubular junction. Postoperative echocardiography and aortography demonstrated a good coaptation of the aortic valve leaflets with trivial aortic regurgitation. Although a rupture site, dissection or carcinomatous pericarditis which is attributable to the two episodes of cardiac tamponade could not be found, pathologic examination of the aneurysm wall revealed intramural blood leakage between the mucoid degenerated media and notably thickened adventitia. In addition, there was thinning and interruption of the elastic fibers of the media. These findings are consistent with a leaking aneurysm which cause the slow development of cardiac tamponade.

Myonephropathic Metabolic Syndrome After Bilateral Aortoiliac Bypass: A Pathogenic Role of Cholesterol Microemboli A Case Report

A 72-year-old man was admitted to our hospital for management of intermittent claudication. A preoperative angiogram showed right common iliac artery occlusion with wellmaintained peripheral flow via collaterals and 50% stenosis of the aortic bifurcation through the left common iliac artery. The authors performed bilateral aortoiliac artery bypass surgery. Immediately following the operation, the left lower limb was cyanotic and cold despite a good pulse in the left dorsalis pedis artery. He suffered from severe pain throughout his entire left calf and part of his thigh. Thrombolytic therapy combined with anticoagulation therapy was started in an attempt to reduce limb ischemia. However, swelling of the left calf increased, and clinical and metabolic manifestations consistent with myonephropathic metabolic syndrome (MNMS) developed. Serum creatine kinase and creatinine rose to 21,600 u/L and 2.8 mg/dl, respectively. His toe became necrotic and a transmetatarsal amputation was done. A skin biopsy taken from the edge of the amputation revealed cholesterol crystals within the capillaries. This report suggests that massive cholesterol microemboli are responsible for MNMS in this patient.