Shingo Chihara

Inhibitory Effect of Milrinone on Cytokine Production After Cardiopulmonary Bypass

BACKGROUND It has been suggested that cyclic adenosine monophosphate-elevating agents suppress cytokine production. To evaluate the effects of milrinone, a phosphodiesterase III inhibitor, on cytokine production after cardiopulmonary bypass, we conducted a prospective randomized study. METHODS Twenty-four patients undergoing coronary artery bypass grafting were randomized to receive either milrinone treatment (milrinone, n = 12) or no milrinone treatment (control, n = 12). Administration of milrinone (0.5 microg x kg(-1) x min(-1)) was started after induction of anesthesia and was continued for 24 hours. Blood samples for determination of plasma cyclic adenosine monophosphate, tumor necrosis factor-alpha, interleukin-1beta, interleukin-6, and interleukin-8 levels were collected perioperatively. RESULTS No significant differences were observed in tumor necrosis factor-alpha and interleukin-8 levels between the groups. Interleukin-1beta and interleukin-6 levels after cardiopulmonary bypass were significantly (p < 0.05) lower in the milrinone group than in the control group. Plasma levels of cyclic adenosine monophosphate increased significantly (p < 0.05) after the administration of milrinone and the levels correlated inversely (r = -0.55, p < 0.01) with interleukin-6 levels. CONCLUSIONS The results indicate that milrinone suppresses cytokine production by elevating cyclic adenosine monophosphate levels in patients undergoing cardiopulmonary bypass. With its positive inotropic and vasodilator activities, milrinone may have antiinflammatory effects.

Effects of intraoperative administration of atrial natriuretic peptide

BACKGROUND Biological activity of endogenous atrial natriuretic peptide (ANP) may decrease during cardiopulmonary bypass. To evaluate the effects of intraoperative administration of exogenous ANP in patients undergoing cardiopulmonary bypass, we conducted a prospective randomized study. METHODS Eighteen patients undergoing mitral valve surgery were randomized to receive either ANP treatment (ANP group; n = 9) or no ANP treatment (control group; n = 9). Atrial natriuretic peptide was given immediately after initiation of cardiopulmonary bypass for 6 hours (0.05 microg x kg(-1) x min(-1)). Plasma ANP, brain natriuretic peptide and cyclic guanosine monophosphate (cGMP) levels, hemodynamic variables and renal function were assessed perioperatively. RESULTS Administration of ANP increased plasma cyclic guanosine monophosphate levels, urine output and fractional sodium excretion, and decreased preload, afterload and plasma brain natriuretic peptide levels significantly (p < 0.05). Plasma cyclic guanosine monophosphate levels correlated with plasma ANP levels (r = 0.95, p = 0.0001), correlated with fractional sodium excretion (r = 0.53, p = 0.02), and correlated inversely with systemic vascular resistance (r = -0.54, p = 0.02). CONCLUSIONS Intraoperative administration of ANP had potent effects on natriuresis and systemic vasodilation by elevating cyclic guanosine monophosphate levels. The results suggest that the technique is useful for the management of hemodynamics and water-sodium retention after cardiopulmonary bypass.

Antiinflammatory effects of colforsin daropate hydrochloride, a novel water-soluble forskolin derivative

BACKGROUND To evaluate the effects of colforsin daropate hydrochloride (colforsin), a water-soluble forskolin derivative, on hemodynamics and systemic inflammatory response after cardiopulmonary bypass, we conducted a prospective randomized study. METHODS Twenty-nine patients undergoing coronary artery bypass grafting were randomized to receive either colforsin treatment (colforsin; n = 14) or no colforsin treatment (control; n = 15). Administration of colforsin (0.5 microg.kg(-1).min(-1)) was started after induction of anesthesia and was continued for 6 hours. Perioperative cytokine and cyclic adenosine monophosphate levels, hemodynamics, and respiratory function were measured serially. RESULTS Marked positive inotropic and vasodilatory effects were observed in patients receiving colforsin. Interleukin 1beta, interleukin 6, and interleukin 8 levels after cardiopulmonary bypass were significantly (p < 0.05) lower in the colforsin group. Plasma levels of cyclic adenosine monophosphate increased significantly (p < 0.05) in the colforsin group, and the levels correlated inversely (r = -0.56, p = 0.002) with the respiratory index after cardiopulmonary bypass. CONCLUSIONS Intraoperative administration of colforsin daropate hydrochloride had potent inotropic and vasodilatory activity and attenuated cytokine production and respiratory dysfunction after cardiopulmonary bypass. The results indicate that the technique can be a novel therapeutic strategy for the systemic inflammatory response associated with cardiopulmonary bypass.

Aortic Dissections Complicating Open Cardiac Surgery: Report of Three Cases

Abstract Between June 1991 and February 1999, three patients suffered ascending aortic dissection as a complication of cardiopulmonary bypass operations with aortic cannulation at our hospital. The dissection occurred during the operation in two of the three patients and several months after the operation in one. Among a total of 2 207 cardiac operations performed during this period, the incidence of perioperative ascending aortic dissection was 0.14%. In addition to visual inspection and palpation, either epicardial or transesophageal echocardiography proved extremely useful for establishing an intraoperative diagnosis of ascending aortic dissection as a complication of open cardiac operation. One of the three patients underwent closed plication but subsequently died of vital organ ischemia. In this case, failure of reapproximation of the injured intima by closed plication might have led to extension of the dissection. Despite prolonged cardiopulmonary bypass and myocardial ischemic time, graft replacement of the ascending aorta was successfully carried out in the other two patients. Thus, we believe that graft replacement of the ascending aorta should be performed for patients with extensive aortic dissection complicating an open cardiac operation.

Surgical treatment of abdominal aortic aneurysm associated with horseshoe kidney: symphysiotomy using harmonic focus.

Coexistence of horseshoe kidney and abdominal aortic aneurysm (AAA) is a rare entity that presents a technical challenge to vascular surgeons. How to approach such an AAA with horseshoe kidney and whether to divide the renal isthmus remains a controversial issue. We report here the successful surgical repair of an AAA with horseshoe kidney via the transperitoneal approach with division of the renal isthmus by Harmonic Focus, which allowed easy division of the isthmus without bleeding. Harmonic Focus, a hand-held type of harmonic scalpel, was thus useful in symphysiotomy of the horseshoe kidney.

Anastomosis of left to right superior vena cava for repair of Unroofed Coronary Sinus

Left superior vena cava (LSVC) draining into the left atrium is a rare congenital cardiac complex. It may appear as an isolated anomaly or as part of more complex cardiac anomalies. Intraatrial rerouting techniques have been the most common approaches to correcting LSVC drainage into the left atrium in patients without a connecting vein. Although these techniques have proved reliable and successful, there are cases in which extracardiac methods for managing this form of anomalous systemic drainage may be preferable. In the present report, we describe an extracardiac approach to the correction of LSVC draining into the left atrium.

Transcatheter coil embolization for patent ductus arteriosus in the elderly: report of a case and review of the published work.

Patent ductus arteriosus is the third most common congenital cardiovascular anomaly, however, it is rarely found in the elderly. We describe a case of patent ductus arteriosus in a 72‐year‐old woman in whom patent ductus arteriosus was successfully managed by transcatheter coil embolization. The patient had been diagnosed with a heart murmur for the first time 1 year earlier at the age of 71. She was asymptomatic but a continuous murmur was heard. Cardiac catheterization revealed migration of a catheter from the main pulmonary artery into the descending aorta through a patent ductus arteriosus and a significant step‐up of oxygen saturation in the main pulmonary artery with a pulmonary‐to‐systemic flow ratio of 1.68. Aortograms demonstrated a communication between the aorta and the pulmonary artery through a patent ductus arteriosus with a minimal diameter of 3.7 mm. Transcatheter coil embolization of the patent ductus arteriosus was successfully carried out with two 0.052‐inch‐diameter Gianturco coils. Doppler echocardiographic study confirmed no residual shunt in the main pulmonary artery after the procedure. Non‐surgical transcatheter occlusion using coil embolization appears to be an effective and minimally invasive technique for treatment of patent ductus arteriosus in the elderly.

Effects of angiotensin-converting enzyme inhibitor during warm blood cardioplegia

BACKGROUND Effects of captopril, an angiotensin-converting enzyme inhibitor, during warm blood cardioplegia were assessed in the blood-perfused, isolated rat heart. METHODS The isolated hearts were arrested for 60 minutes with warm blood cardioplegia given at 20-minute intervals and were reperfused for 60 minutes. The control group (n = 10) received standard cardioplegia and the captopril group (n = 10) received cardioplegia supplemented with captopril (2 mmol/L). Cardiac function, myocardial metabolism, and cardiac release of circulating adhesion molecules were assessed before and after cardioplegic arrest. RESULTS Left ventricular end-diastolic pressure and -dp/dt were significantly (p<0.05) lower and coronary blood flow was significantly (p<0.05) greater in the captopril group than the control group during reperfusion. The captopril group resulted in significantly (p<0.05) less cardiac release of lactate, thiobarbituric acid reactive substances during reperfusion. Cardiac release of intercellular adhesion molecule-1 was significantly (p<0.05) less in the captopril group at 60 minutes of reperfusion. CONCLUSIONS The results suggest that supplementation of captopril during warm blood cardioplegia provides superior myocardial protection by suppressing lipid peroxidation and leukocyte-endothelial cell interaction during reperfusion.

Pulsatile Varicose Veins Secondary to Severe Tricuspid Regurgitation: Report of a Case Successfully Managed by Endovenous Laser Treatment.

We report a case of pulsatile varicose veins successfully managed by endovenous laser treatment (EVLT) of the great saphenous vein (GSV). A 77-year-old woman taking an anticoagulant was transferred to our hospital for pulsatile varicose veins complicated with repeated venous bleeding from an ulcer of her left lower leg. Doppler echocardiography showed severe tricuspid regurgitation, and duplex ultrasonography revealed an arterial-like pulsating flow in the saphenofemoral junction and along the GSV, but an arteriovenous fistula, obstruction of the deep veins, and the distal incompetent perforators were not detected. Because of a significant bleeding risk due to elevated venous pressure and anticoagulant therapy, EVLT was performed for the GSV, which resulted in the complete occlusion of the GSV and healing of the ulcer. EVLT presents a safe and useful therapeutic technique for pulsatile varicose veins in the limbs.

Surgical treatment for graft stenosis after repair of an interrupted aortic arch: Report of two cases

We report herein two cases of patients who underwent successful reoperation for graft stenosis after repair of an interrupted aortic arch (IAA). The first patient was a 10-year-old girl who suffered from upper limb hypertension 9 years after her initial operation. Cardiac catheterization revealed a pressure gradient of 55mmHg across the repaired arch. At reoperation, a left subclavian turndown anastomosis was performed, following which the hypertension resolved and a cardiac catheterization done 5 years later demonstrated sufficient growth of the restored arch with no significant gradient. The second patient was a 17-year-old boy who suffered from general fatigue and intermittent hypertension 12 years after his initial operation. Cardiac catheterization revealed a gradient of 60mmHg across the repaired arch. He underwent an extraanatomic ascending to descending aortic bypass employing an additional 18-mm graft, and a postoperative cardiac catheterization showed no gradient between the ascending and descending aorta. Our experience has shown that IAA should be repaired without prosthetic grafts if possible. Although extraanatomic bypass is useful for reducing the operative risks at reoperation, a large graft should be used to avoid the need for a third operation. For young children expected to outgrow a second graft, performing an endogenous anastomosis, such as a left subclavian turndown anastomosis, should be considered as an alternative.