Nanao Negishi

Low-dose continuous infusion of human atrial natriuretic peptide during and after cardiac surgery

BACKGROUND We evaluated the effects of human atrial natriuretic peptide (hANP) during cardiopulmonary bypass (CPB). METHODS Forty patients undergoing coronary artery bypass grafting were investigated. A group of patients given hANP for 24 hours from the start of CPB (hANP group) was compared with a non-hANP group. Parameters examined were hemodynamics, urine volume, dosage of furosemide, respiratory index, pleural effusion, ANP, cyclic guanosine monophosphate, renin activity (renin), angiotensin-II, aldosterone, and glomerular filtration rate. RESULTS Central venous pressure, systemic vascular resistance index, and pulmonary vascular resistance index were significantly lower in the hANP group than in the non-hANP group. The hANP group showed significantly higher levels of ANP, cyclic guanosine monophosphate, glomerular filtration rate, and respiratory index, and significantly lower levels of renin, angiotensin-II, aldosterone, and pleural effusion, as compared with the non-hANP group. The dosage of furosemide was significantly lower and the urine volume was significantly larger in the hANP group. CONCLUSIONS hANP can satisfactorily compensate for the shortcomings of CPB by decreasing the peripheral vascular resistance, suppressing the renin-angiotensin-aldosterone system, and exerting a strong diuretic effect.

Optimal treatment of type B acute aortic dissection: long-term medical follow-up results.

BACKGROUND The aim of this study is to assess the long-term outcome of medical treatment and determine recent surgical indications for type B acute aortic dissection. METHODS In the last 8 years, 79 patients were admitted to our hospital with type B acute aortic dissection. We medically treated patients at the time of onset, regardless of the aortic diameter and blood patency status in the false lumen. If the maximum diameter of dissected aorta exceeded 60 mm in any stage, early or elective surgery was performed. The mean follow-up duration was 41.2 months. We evaluated operation free rate and actuarial survival rate. RESULTS Thirteen patients underwent early or elective operations of the descending aorta. At the time of onset, the maximum aortic diameter of these patients was significantly larger than that of medically managed patients (55.8 +/- 4.4 mm vs 44.6 +/- 8.2 mm; p = 0.0004). Two patients underwent emergency axillo-femoral bypass for leg ischemia. Of the other 64 patients, who were medically managed, 2 patients had type A dissection develop during follow-up, 3 died during the initial hospital stay (1 from rupture, 1 from bronchial asthma, and 1 from gut ischemia), and 1 died of pneumonia 6 months after onset. Operation free rate was 98.6% at 1 month, 90.0% at 1 year, 78.7% at 3 years, and 69.5% at 8 years. Actuarial survival rate of medically managed patients was 98.4% at 1 month and 93.5% at 8 years. CONCLUSIONS Medical treatment of type B acute aortic dissection produced good results. Surgical intervention for type B dissection should be done when the maximum aortic diameter exceeds 60 mm.

Staple Line Reinforcement with Fleece-Coated Fibrin Glue (TachoComb) After Thoracoscopic Bullectomy for the Treatment of Spontaneous Pneumothorax

BackgroundWe investigated the cause of pneumothorax recurrence after thoracoscopic surgery and the effectiveness of staple line reinforcement with fleece-coated fibrin glue (TachoComb) in the prevention of postoperative pneumothorax recurrence.MethodsFrom April 3, 1992 to the end of December 2005, thoracoscopic bullectomy was performed on 499 patients of primary spontaneous pneumothorax. The causes of recurrence were investigated on 39 patients on the basis of surgical observations, preoperative chest computed tomography, and so on. The most common cause was new bulla formation (37 cases), 19 of which were apparently related to the staple line (within 1 cm of the staple lines) and 15 of which were not related to the staple line. After 2000, we stopped using forceps to grasp lungs and we have reinforced the staple line by applying fleece-coated fibrin glue.ResultsThe staple line reinforced with fleece-coated fibrin glue, or sprayed with fibrin glue solution and the untreated group (bullectomy only with staples) were compared, and the recurrence rates were 1.22%, 7.25%, and 10.00%, respectively (P = 0.0006021).ConclusionsThe recurrence rate after thoracoscopic bullectomy with fleece-coated fibrin glue was significantly lowered and we consider this procedure to be the treatment of choice for the management of spontaneous pneumothorax.

Surgery for Ruptured Abdominal Aortic Aneurysm with an Aortocaval and Iliac Vein Fistula

The purpose of this study was evaluate the operative procedure and outcome of abdominal aortic aneurysm (AAA) patients with aortocaval fistula (ACF) and iliac vein fistula. From 1982 through 2004, we experienced five AAA patients associated with spontaneous aortocaval and aortoiliac venous fistula who underwent repair of AAA. Three patients were in hypovolemic shock, including one patient with cardiopulmonary arrest on admission who required cardiopulmonary resuscitation before surgery. These three ACF patients with hypovolemic shock underwent emergency operation and two patients with stable hemodynamic state underwent urgent operation. One of two ACF patients with stable condition was associated with unstable angina. One AAA patient with ACF-complicated angina underwent AAA repair with coronary artery bypass grafting; the remaining four patients underwent 3 bifurcated graft and 1 tube graft implantation. All surgical treatment of the fistula included direct closure within the aorta under digital compression in four patients and inferior vena cava clamp in one. The mortality rate was 25%. One ACF patient with retroperitoneal hematoma died of bleeding. Survival for ACF depends on early diagnosis and prompt surgical repair. Aortocaval fistula complicated with a rupture of aneurysm into retroperitoneal space had a severe fatal prognosis compared with uncomplicated ACF.

Evaluation of valve sound and its effects on ATS prosthetic valves in patients’ quality of life

BACKGROUND We interviewed patients and carried out frequency analyses to compare the closing sounds of ATS and St. Jude Medical (SJM) prosthetic valves. METHODS Forty-five patients undergoing valve replacements using ATS valves were investigated. We interviewed patients at 1 month and 1 year after the operation, and carried out frequency analysis to investigate the prosthetic valves closing sound. RESULTS According to the results of the interviews, 84.4% of patients with ATS valves were not aware of the valve sounds. ATS valves scored significantly lower than SJM valves on audibility of the valve sound, disturbance during daytime, sleep disturbance, request for replacement with a soundless prosthetic valve, audibility to others, and noise index. According to the frequency analysis on the prosthetic valves closing sound, the sound peak of the ATS valves was around 1.2 kHz, and the sound pressure of the ATS valves was significantly lower than that of the SJM valves. CONCLUSIONS Though a further long-term observation on thromboembolism and hemolysis is needed for evaluation of prosthetic valves, the ATS valve is presently considered to impart a better quality of life.

Efficacy of continuous low-dose human atrial natriuretic peptide given from the beginning of cardiopulmonary bypass for thoracic aortic surgery.

PurposeCardiac surgery performed under cardiopulmonary bypass (CPB) causes abnormalities of the renin-angiotensin-aldosterone system, resulting in decreased urine output and an accumulation of water in the third space. We studied the efficacy of continuous low-dose human atrial natriuretic peptide (hANP) in patients undergoing thoracic aortic surgery.MethodsWe divided 40 patients undergoing thoracic aortic surgery into two groups: the hANP group, which received 0.02 μg/kg per minute of hANP and the non-hANP group, which did not. The hemodynamics, urine output, intensive care unit (ICU) and hospital stay, bleeding volume, homologous blood transfusion volume, furosemide dose, corrected KCl volume, and postoperative respiratory, hepatic, and renal function were compared in the two groups.ResultsThe urine output during CPB and from CPB weaning to return to ICU was significantly better in the hANP group. The bleeding volume, homologous blood transfusion volume, furosemide dose, and corrected KCl volume were all significantly less in the hANP group.ConclusionsThese findings support the consensus that hANP exerts its diuretic effects to their full potential when administered continuously at low doses during thoracic aortic surgery. We found it to be effective for postoperative hemostasis and for preventing ischemic reperfusion injury.

Heat and pain sensations induced by arterial injection of low-osmolality contrast media: a comparison of patients' discomfort with ionic saline, nonionic glucose, and vasodilator nitrate.

C linical symptoms such as heat and pain are two of the most frequent and finpleasant adverse effects experienced after intravascular injection of iodinated contrast media. Recently, nonionic dimeric contrast media (iotrolan, iiodixanol) have been developed [1], and their osmolality has been reduced to the physiologic level. However, subjective discomforts associated with these contrast media have not yet been eliminated. Although it has been established that heat and pain are caused mainly by tile high osmolality of the contrast media [2], it is possible that other factors also may play active roles. The aim of this study was to determine what factors and mechanisms are involved in causing heat and pain from the administration of the contrast media presently being used. The following agents were analyzed in our study: glucose as a model of a nonionic agent, saline (NaCl) as a model of an ionic agent, and nitrate as a vasodilator. Clinical studies on heat and pain induced by contrast media have been conducted [1, 3-7], but studies with test solutions involving actual patients have not been reported [8, 9]. Our study was designed to obtain the expression of sensations, which could be obtained only from human volunteers.

An impending rupture of a celiac artery aneurysm in a patient with Behçet’s disease — Extra-anatomic aorto-common hepatic artery bypass: Report of a case

A celiac artery aneurysm associated with Behçet’s disease is extremely rare. We herein present the case of successful surgical treatment for an impending rupture of a large celiac artery aneurysm with a wide proximal neck in a patient associated with Behçet’s disease. To our knowledge, this is the first report of a procedure involving extra-anatomic aorto-common hepatic artery (CHA) bypass through the retroperitoneal space implanting a 6-mm expanded polytetrafluoroethylene graft. An 18-month postoperative magnetic resonance angiography scan showed a good patency of the aorto-CHA graft without an anastomotic pseudoaneurysm in a closure of aorta and anastomoses.

Comparative study of harvest-site complications following coronary artery bypass grafting between the radial artery and the saphenous vein in identical patients.

PurposeThe aim of this study was to assess the early outcome for complications associated with the radial artery harvest site, in comparison to using the saphenous vein, in patients harvested for both vessels.MethodsDuring the last 2 years, 134 radial arteries were used in 133 patients, and the saphenous vein was also concomitantly used in 94 patients. We assessed the post-harvest forearm perception using a questionnaire that contained two statements regarding pain and numbness in those 94 patients. The incidences of the harvest-site hematoma and infection were also compared between both the arms and legs where the grafts were harvested.ResultsNumbness of the harvest site was indicated in 26.6% (radial artery) and 33.0% (saphenous vein), respectively (P = 0.4252). Hematoma was found in 6.4% and 12.8%, respectively (P = 0.2152). On the other hand, the incidences of pain and wound infection were significantly lower in the radial artery sites (pain: 1.1% vs 23.4%, P = 0.0002; infection: 2.1% vs 11.7%, P = 0.0182).ConclusionsOur early experience suggests that the use of the radial artery is safe and also demonstrates a lower incidence of harvest-site complications than saphenous vein harvesting in patients where both vessels are used as harvest sites.

Clinical evaluation of the Gyro Pump C1E3 as a cardiopulmonary bypass pump.

The Gyro Pump C1E3 is a new centrifugal pump with numerous features, including a ceramic pivot bearing system, secondary vanes, and an eccentric inlet port. To evaluate its biocompatibility, antithrombogenicity, and produced hemolysis, we used the Gyro Pump during cardiopulmonary bypass (CPB) for coronary artery bypass grafting (CABG) cases to compare it with the BioMedicus pump. From September 1998 to February 1999, 30 consecutive patients underwent CABG under conventional CPB. Fifteen patients were supported by the Gyro Pump C1E3 (Group G), and the remaining 15 patients, by a BioMedicus BP-80 pump (Group B). In both groups, flow rate was equivalent. Blood samples were taken as follows: preoperative, 60 minutes after the end of the procedure, and at postoperative days (POD) 0, 1, and 2. We evaluated the plasma free hemoglobin (free Hb) as an indication of hemolysis; beta-thromboglobulin (beta-TG) and platelet factor four (PF-4) as an indication of platelet deterioration; C3, C4, CH50 for complement activation; coagulation parameters, fibrinolytic factor, thrombomodulin, nitric oxide (NO), and endothelin as an indication of endothelial deterioration. This was the first clinical sized Gyro Pump CIE3. De-airing from the pump was easily accomplished via the eccentric oblique inlet port. The system, including its console, was easily and simply controlled. Perioperative laboratory data were not markedly changed in either group with demonstrated equivalence for biocompatibility and hemolysis. After pumping, no thrombus formation or pivot wear were observed inside the pump. This atraumatic, small centrifugal pump appears well suited not only for CPB but also for circulatory support.