Shigeki Horikoshi

Use of the 21-mm Björk-Shiley Monostrut valve in patients with a narrow aortic root.

Technical considerations regarding the insertion of 21-mm Björk-Shiley Monostrut valves, particularly regarding decalcification of a calcified annulus with an ultrasonic surgical dissector, in patients with aortic stenosis and a narrow aortic root are described. Short-term follow-up (mean(s.d.) 37(10) months) is also presented. Ten adults whose body surface area ranged from 1.26 to 1.47 m2 underwent implantation of a 21-mm valve without outflow patch or annuloplasty. One operative death occurred; there were no other complications. The New York Heart Association functional class decreased from a mean of 3.2 before surgery to 1 in all cases. The mean(s.d.) end-diastolic volume decreased from 129(44) ml to 80(21) ml, and the end-systolic volume from 41 (21) ml to 27(10) ml (P< 0.01). The mean(s.d.) maximum velocity, as measured by Doppler echocardiography in the aortic position, decreased from 4.35(0.55) m/s to 2.42(0.59) m/s (P< 0.01). This degree of improvement was not meaningfully different from that of the 23-mm valve. However, there was a negative correlation between the reduction in left ventricular mass and body surface area (r = −0.72, P< 0.03). It is concluded that the 21-mm Björk-Shiley Monostrut valve can be inserted using a modified technique in most patients with a narrow aortic root. This size valve is satisfactory when the patients body surface area is < 1.45 m2.

Perfusion pressure control by adenosine triphosphate given during cardiopulmonary bypass

Abstract Administration of exogenous adenosine triphosphate (ATP) as a vasodilator during cardiopulmonary bypass was assessed in consecutive adult patients (n = 24) who demonstrated a high arterial perfusion pressure (mean, >90 mm Hg). The action of ATP was characterized by rapid induction and stabilization of the blood pressure level. The dose of ATP ranged from 0.68 to 2.68 mg/min. Within 1 minute after the administration, there was a significant reduction in the perfusion pressure from 102 ± 18 mm Hg (mean ± standard deviation) to 72 ± 19 mm Hg. The ATP was then able to maintain the desired pressure of 69 ± 12 mm Hg at 5 minutes, 67 ± 12 mm Hg at 10 minutes, and consistent values thereafter. After the ATP administration was discontinued, there was a prompt recovery of pressure without bradyarrhythmia. The frequency and amount of inotropes used were consistent with the control group (n = 26). Although the administration of ATP reduced the increase in serum catecholamine concentration, there were no significant changes in other vasoactive mediators (eicosanoid, angiotensin II, endothelin) between the two groups during cardiopulmonary bypass. There was neither an accumulation of metabolic products (uric acid, phosphate) nor a decrease in the level of divalent cation (Ca 2+ ), which is observed when the cations combine with phosphates or adenosine nucleotides. This study confirmed the efficacy and safety of ATP infusion during cardiopulmonary bypass.

Successful repair of a rare type of total anomalous pulmonary venous drainage

This report describes a 2-month-old female infant with a rare supracardiac type of total anomalous pulmonary venous drainage. The intrapulmonary drainage of the pulmonary veins was into the right lung from the left lung. The anomaly was successfully repaired by atriocavoplasty.

Two-staged Operation for an Infected Common Illiac Arterial Aneurysm.

細菌感染による感染性腹部動脈瘤は腹部動脈瘤疾患において比較的稀とされており, またその手術時期や血行再建法に関して種々の見解が議論されている. 今回われわれは, 二期的に手術を施行し良好な経過を得た感染性腹部動脈瘤症例を経験したので若干の文献的考察を加え報告する. 症例は56歳, 男性. 糖尿病管理目的にて通院中のところ, 全身倦怠, 発熱が増強. 精査目的にて入院し施行した腹部CT, 腹部大動脈造影検査において, 左総腸骨動脈に曩状の動脈瘤が認められ, また血液培養検査にてサルモネラ菌が検出されたため, 同菌による感染性動脈瘤と診断した. 手術は, 初回術中所見よりまず感染巣の処置と extraanatomical bypass を行い, ついで anatomical grafting とする二期的手術を施行, 術後は6週間抗生剤治療を継続した. 術後経過は良好で軽快退院となり, 術後6カ月を経た現在も感染再燃徴候はみられていないが, 今後も感染症の再燃に対する慎重な経過観察が重要と考えられた.

Clinical advantages and myocardial protection of normothermal CPB —Comparison with hypothermal CPB—

We studied the clinical advantages and myocardial protection of normothermal CPB with comparing to hypothermal CPB. 22-cases of adult CABG were classified under two groups, according to the temperature of CPB. (Normothermal group: 37 degrees C, Hypothermal group: 32 degrees C) In both groups, the assistant CPB time after aortic declamp, the use of cardioversion that meaned the spontaneous recovery to sinus rhythm appeared or not, the dose of cathecholamines in- and post-operation, and the amounts of postoperative bleeding (after 6 h and 12 h) were compared as the clinical results and the data of CPK-MB, Myocin LC-II, and Troponin-T were measured as the effects of myocardial protection. The method of myocardial protection was the intermittent antegrade cold blood cardioplegia with terminal warm blood for all cases. As a result, the assistant CPB time after aortic declamp, the use of cardiovasion, and the amounts of postoperative bleeding (both of 6 h and 12 h) were less in normothermal group rather than in hypothermal group. (p < 0.05). However we had no differences about the dose of cathecholamines in post-operation and the data of three items between two groups. So, it suggests that the sufficient effects of myocardial protection could be obtained in normothermal CPB as in hypothermal CPB. Therefore we conclude that normothermal CPB could provide some clinical advantages, such as shortening CPB time, recovery of sinus rhythm, and prevention of postoperative bleeding, compared to hypothermal CPB and sufficient myocardial protection.