Double-σ-Bonded Close-Shell Dimers and Peroxy-Linked Open-Shell Dimer Derived from a C3 Symmetric Trioxophenalenyl Neutral Diradical.

A novel neutral diradical of π-extended phenalenyl derivative having three oxo-groups, tri-tert-butyl-1,4,7-trioxophenalenyl, and two types of the corresponding σ-dimers were investigated. Quantum chemical calculations showed that the neutral diradical is in triplet ground state having doubly degenerate singly occupied molecular orbitals. The neutral diradical undergoes a σ-dimerization, generating two types of σ-dimers immediately after the preparation. One of the σ-dimers, which was selectively generated in the crystalline state, was a close-shell dimer linked through double-σ-bonds on the phenalenyl skeleton with a long C-C bond length of 1.66 Å. The other σ-dimer, which existed only in the solution state, was a peroxy-linked open-shell dimer in which one σ-bond was formed between two oxygen atoms. Furthermore, the temperature-dependent 1 H NMR and ESR spectra revealed that these σ-dimers are in equilibrium in the solution state by the reversible σ-bond formation/cleavage via the neutral diradical as a key intermediate.

[Spontaneous Renal Rupture of Acquired Cystic Kidney Disease after Coronary Artery Bypass Grafting:Report of a Case].

We described a hemodialysis patient with spontaneous renal rupture of acquired cystic kidney disease (ACKD) after off-pump coronary artery bypass grafting(OPCAB). A 53-year-old man was transfer to our hospital with a diagnosis of unstable angina pectoris. He became ventilated due to congestive heart failure 3 days and underwent OPCAB on schedule 6 days after hospitalization. He suddenly complainted of colicky frank pain 31 days after surgery. Computed tomography (CT) demonstrated bulky hematoma with swollen kidney. Treatment included blood transfusions, withdrawal of anticoagulation, administration of vitamin K, and bed rest. The patient's symptom disappeared. A month later CT showed that the hematoma had been absorbed.

[Coronary Artery Bypass Grafting to the Left Anterior Descending Artery via Anterior Minithoracotomy after Surgery for Acute Papillary Muscle Rupture;Report of a Case].

We presented a case with chronic occlusion of the left anterior descending artery(LAD) after mitral valve replacement (MVR). An 80-year-old man was transferred to our hospital with a diagnosis of acute myocardial infarction. Before coronary angiography, the patient suddenly fell in a state of cardiogenic shock. Echocardiography revealed acute mitral regurgitation due to anterior papillary muscle rupture. Although emergency MVR was performed, introduction of percutaneous cardiopulmonary support (PCPS) and intraaortic balloon pumping ( IABP) was needed to come off cardiopulmonary bypass. Postoperative coronary angiography revealed chronic occlusion of LAD. The left internal thoracic artery was anastomosed to LAD via anterior minithracotomy to avoid median re-sternotomy. The postoperative course was uneventful and the cardiac function improved.

Hybrid operation for combined aortic arch aneurysm and aortic root dilation in a Jehovah's witness patient.

Aortic surgery for Jehovah's Witness patients with extended aneurysms is challenging. The present report describes a case of a 65-year-old male Jehovah's Witness with aortic aneurysm that extended from the ascending to the transverse aortic arch. Two-stage hybrid operation was performed as follows: ascending aortic replacement with debranching of brachiocephalic artery, followed by extra-anatomic bypass of cervical arteries, and thoracic aortic stent-grafting. The patient fully recovered without complication, and the lowest hemoglobin concentration during the hospital admission was 9.5 g/dL. We conclude that the hybrid procedure was effective in securing a margin of safety for bloodless aortic surgery.

Bilateral axillary arterial aneurysms in siblings with Marfan syndrome.

Axillary arterial aneurysm associated with Marfan syndrome is an extremely rare and dangerous disease because of its potential risk for rupture and impairment of neurologic function in the upper extremities. Treatment of large axillary aneurysms can be surgically challenging because the axillary artery is anatomically located under the clavicle bones and the brachial plexus runs dorsal to the aneurysm. We report 2 cases of bilateral axillary arterial aneurysms in brothers with Marfan syndrome. Revival of a novel approach and cautious attempts during the procedures are described in both cases.

Control of Exchange Interactions in π Dimers of 6-Oxophenalenoxyl Neutral π Radicals: Spin-Density Distributions and Multicentered-Two-Electron Bonding Governed by Topological Symmetry and Substitution at the 8-Position.

The tri-tert-butylphenalenyl (TBPLY) radical exists as a π dimer in the crystal form with perfect overlapping of the singly occupied molecular orbitals (SOMOs) causing strong antiferromagnetic exchange interactions. 2,5-Di-tert-butyl-6-oxophenalenoxyl (6OPO) is a phenalenyl-based air-stable neutral π radical with extensive spin delocalization and is a counter analogue of phenalenyl in terms of the topological symmetry of the spin density distribution. X-ray crystal structure analyses showed that 8-tert-butyl- and 8-(p-XC6H4)-6OPOs (X=I, Br) also form π dimers in the crystalline state. The π-dimeric structure of 8-tert-butyl-6OPO is seemingly similar to that of TBPLY even though its SOMO-SOMO overlap is small compared with that of TBPLY. The 8-(p-XC6H4) derivatives form slipped stacking π dimers in which the SOMO-SOMO overlaps are greater than in 8-tert-butyl-6OPO, but still smaller than in TBPLY. The solid-state electronic spectra of the 6OPO derivatives show much weaker intradimer charge-transfer bands, and SQUID measurements for 8-(p-BrC6H4)-6OPO show a weak antiferromagnetic exchange interaction in the π dimer. These results demonstrate that the control of the spin distribution patterns of the phenalenyl skeleton switches the mode of exchange interaction within the phenalenyl-based π dimer. The formation of the relevant multicenter-two-electron bonds is discussed.

Eradication of active infective endocarditis with submitral abscess infiltrating to annular calcification.

The case is reported of a 72-year-old man in whom surgery was performed to treat infective endocarditis in association with mitral leaflet vegetation, a submitral abscess that penetrated the pericardial cavity, and posterior mitral annular calcification. Extensive debridement of the posterior left ventricle and atrium, posterior mitral annulus and mitral annular calcification was performed, after which the atrioventricular wall was reconstructed using a theta-shaped patch and a biological mitral valve replaced.

The effect of atmospheric pressure on ventricular assist device output.

The effect of cabin pressure change on the respiratory system during flight is well documented in the literature, but how the change in atmospheric pressure affects ventricular assist device (VAD) output flow has not been studied yet. The purpose of our study was to evaluate the change in VAD output using a mock circulatory system in a low-pressure chamber mimicking high altitude. Changes in output and driving pressure were measured during decompression from 1.0 to 0.7 atm and pressurization from 0.7 to 1.0 atm. Two driving systems were evaluated: the VCT system and the Mobart system. In the VCT system, output and driving pressure remained the same during decompression and pressurization. In the Mobart system, the output decreased as the atmospheric pressure dropped and recovered during pressurization. The lowest output was observed at 0.7 atm, which was 80% of the baseline driven by the Mobart system. Under a practical cabin pressure of 0.8 atm, the output driven by the Mobart system was 90% of the baseline. In the Mobart system, the output decreased as the atmospheric pressure dropped, and recovered during pressurization. However, the decrease in output was slight. In an environment where the atmospheric pressure changes, it is necessary to monitor the diaphragmatic motion of the blood pump and the driving air pressure, and to adjust the systolic:diastolic ratio as well as the positive and negative pressures in a VAD system.

Design and Synthesis of a C3 Symmetrical Phenalenyl Derivative with Three Oxo Groups by Regioselective Deoxygenation/Oxygenation.

Tri-tert-butylated 4,7-dihydroxyphenalenone was designed and synthesized from a corresponding 4,9-dimethoxyphenalenone derivative by regioselective deoxygenation/oxygenation. The 4,7-dihydroxyphenalenone derivative showed a chromic behavior accompanied by protonation and deprotonation, giving monocation and dianion species, respectively, and their C3 symmetric electronic structures were elucidated by experimental and theoretical methods.

Continuous hemodiafiltration in children after cardiac surgery.

Acute renal failure (ARF) after congenital cardiac surgery remains a serious complication and leading cause of morbidity and mortality. Continuous hemodiafiltration (CHDF) is presently accepted for pediatric applications. We retrospectively evaluated the effects of CHDF against ARF after congenital cardiac surgery at our hospital. We analyzed data from seven patients aged 23 days to 9 years and weighing 1.7-22.4 kg requiring dialysis therapy using CHDF after congenital cardiac surgery between April 2002 and January 2009. One patient who died could not be weaned from extracorporeal membrane oxygenation support and another died of multiple organ failure. Renal function recovered to normal in the other five (71%) patients. Treatment by CHDF lasted from 14 to 680 h and net ultrafiltration was 3.5 ± 1.4 mL/kg/h. Serum creatinine and urea concentrations were, respectively, 2.3 ± 1.6 and 43.7 ± 17.0 mg/dL before, and 0.5 ± 0.2 and 13.5 ± 8.1 mg/dL, after CHDF (P < 0.05). Thrombocytopenia developed in all patients, and platelet concentrates (0.76 ± 0.7 mL/kg/h) were infused during CHDF. Hypotension developed after changing the CHDF set in one patient. We suggest that CHDF is an effective alternative strategy for treating renal dysfunction after congenital cardiac surgery.

Hydrodynamics of aortic cannulae during extracorporeal circulation in a mock aortic arch aneurysm model.

This study was designed to analyze flow pattern, velocity, and strain on the aortic wall of a glass aortic arch aneurysm model during the extracorporeal circulation, and to elucidate the characteristics of flow pattern in three different aortic cannulae. Different patterns of large vortices and helical flow were made by each cannula. With the curved end-hole cannula, the high velocity flow (approximately 0.6-0.8 m/s) was blowing to the aneurismal wall without attenuating the strain rate tensor (approximately 0.2-0.25/s). With the dispersion cannula and the Soft-Flow cannula, cannular jet was attenuated in the ascending aorta creating a large vortex at a velocity less than 0.5 m/s, and the strain rate tensor on the aneurismal wall was small (less than 0.15/s). In conclusion, end-hole cannula should not be used in the operation of aortic arch aneurysm. Dispersion-type aortic cannulae were less invasive on the aortic arch aneurismal wall, but particular attention to alternative cannulation sites should be paid in cases with severe atherosclerosis on the ascending aortic wall.

Prevalence of venous thromboembolism in neurosurgical patients.

This study was conducted to clarify the prevalence of venous thromboembolism (VTE) in neurosurgical patients. Prospective study for venous thromboembolism screening after neurosurgery was conducted. Thirty-seven patients were screened by ultrasonography for deep vein thrombosis in the lower extremities at an average of 12 days postoperatively. All patients received standard thromboprophylaxis using graded compression stocking with/without intermittent pneumatic compression following the VTE prevention guidelines. Definitive diagnosis of venous thromboembolism was made by contrast-enhanced whole-body computed tomography. Prevalence of deep vein thrombosis of the lower legs was 13.5% (5/37). Incidence of pulmonary embolism was 60% (3/5) in patients having deep vein thrombosis. All patients having venous thromboembolism were asymptomatic. In high-risk patients, VTE prevalence after neurosurgery was high even under mechanical prophylaxis. Additional pharmacological prophylaxis should be considered for patients with high risk of VTE.

Computer-simulated fluid dynamics of arterial perfusion in extracorporeal circulation: From reality to virtual simulation.

BACKGROUND: Atheroembolism due to aortic manipulation remains an unsolved problem in surgery for thoracic aortic aneurysm. The goal of the present study is to create a computer simulation (CS) model with which to analyze blood flow in the diseased aorta. METHOD: A three-dimensional glass model of the aortic arch was constructed from CT images of a normal, healthy person and a patient with transverse aortic arch aneurysm. Separately, a CS model of the curved end-hole cannula was created, and flow from the aortic cannula was recreated using a numerical simulation. RESULTS: Comparison of the data obtained by the glass model analyses revealed that the flow velocity and the vector of the flow around the exit of the cannula were similar to that in the CS model. A high-velocity area was observed around the cannula exit in both the glass model and the CS model. The maximum flow velocity was as large as 1.0 m/s at 20 mm from the cannula exit and remained as large as 0.5 to 0.6 m/s within 50 mm of the exit. In the aortic arch aneurysm models, the rapid jet flow from the cannula moved straight toward the lesser curvature of the transverse aortic arch. The locations and intensities of the calculated vortices were slightly different from those obtained for the glass model. CONCLUSION: The proposed CS method for the analysis of blood flow from the aortic cannulae during extracorporeal circulation can reproduce the flow velocity and flow pattern in the proximal and transverse aortic arches.

[Surgical treatment of aortic root disease].

We reviewed aortic root disease and operative procedures. Between January 1982 and December 2008, aortic root operation was performed for 58 patients with various aortic root disease. We chose Bentall type operations in extensive root destructive cases and urgent or reoperative cases. Overall in-hospital mortality was 8.6% (5/58). Four patients (7.5% of survivors) died during the period of followup. Actuarial survival at 15 years was 92%. Freedom from cardiovascular event at 10 and 15 years was 81% and 27%, respectively. Of 5 reoperations in 5 patients, only 1 was required due to complications of the initial Bentall type operation. The Bentall type operations resulted in a durable result. Although, in Marfan syndrome, freedom from cardiovascular event was lower than that in non-Marfan syndrome, actuarial survival rate was equal with non-Marfan syndrome. Close observation is necessary for detecting cardiovascular event, especially in Marfan syndrome.

Curve-structured phenalenyl chemistry: synthesis, electronic structure, and bowl-inversion barrier of a phenalenyl-fused corannulene anion.

We have demonstrated the features of curve-structured phenalenyl chemistry, for the first time. A phenalenyl-fused corannulene anion has been designed by the annelation of a six-memberd ring across peri-positions of corannulene and generated as a stable species in a degassed solution. The 1H and 13C NMR spectra have shown the highly symmetrical structure and high-field shifts of protons and carbons at the asterisked positions in the chemical structure, indicating the occurrence of large negative charge densities at these positions. These results well agree with the HOMO picture and the electrostatic potential surface, demonstrating the phenalenyl anion-type electronic structure is retained in the curved-surface pi-system. The calculated bowl-inversion barrier of the anion (11.3 kcal/mol) is larger than that of corannulene (9.2 kcal/mol) because of peri-annelation of the corannulene skeleton. The calculations of the barriers of the neutral radical (12.6 kcal/mol), radical dianion (8.1 kcal/mol), and trianion (5.4 kcal/mol) of the phenalenyl-fused corannulene have exhibited a stepwise flattening of the curvature with increase in negative charge. Therefore, we have revealed that the bowl-inversion barrier of the anion is governed by the setoff of the peri-annelation and negative charge effects.

Decreased plasma and cardiac matrix metalloproteinase activities in patients with coronary artery disease and treated with pravastatin.

Matrix metalloproteinase (MMP), which is activated by oxidative stress, plays an important role in the development of ventricular remodeling in coronary artery disease. Pravastatin is shown to reduce oxidative stress. We tested the hypothesis that cardiac oxidative stress and MMP activity are reduced in patients with coronary artery disease and treated with pravastatin. Forty-eight patients who underwent coronary artery bypass graft surgery (CABG) were studied. Twenty-four patients had the serum low-density lipoprotein (LDL) cholesterol level >2.59 mM, and were treated with pravastatin (10 mg/day) for 2 months before CABG (pravastatin group). The other 24 had LDL cholesterol< or =2.59 mM, and were untreated (control group). The plasma and pericardial MMP-2 and MMP-9 activities were measured by gelatin zymography, and MMP-2 and MMP-9 levels, and pericardial 8-iso-prostagrandin F2alpha (8-iso-PGF2alpha) level, a maker of oxidative stress, by enzyme-linked immunosorbent assay. The plasma and pericardial MMP-2 and MMP-9 activities and levels were all lower by 20-30% in pravastatin than in control group (all P<0.05). The pericardial 8-iso-PGF2alpha level was lower in pravastatin than in control group (38+/-4 vs 64+/-7 pg/ml, P<0.05). The pericardial MMP-2 and MMP-9 activities were positively correlated with the pericardial 8-iso-PGF2alpha level (r=0.57 and 0.47, respectively, both P<0.01). Thus, cardiac oxidative stress and MMP activities are reduced in patients with coronary artery disease and treated with pravastatin, which may be beneficial in preventing and reducing ventricular remodeling.

Increased superoxide radical with a decrease in vascular endothelial growth factor and inducible nitric oxide synthase level leads to the progression of left ventricular hypertrophy in a pressure-overload rat heart model.

PURPOSE: This study was designed to evaluate the relationship among free radicals and vascular endothelial growth factor (VEGF) and inducible nitric oxide synthase (iNOS) during the progression of left ventricular hypertrophy (LVH) in pressure-overload rat heart. METHODS: Hypertrophied rat heart created by abdominal aortic banding at the age of 4 weeks was studied at the ages of 14, 15, 18, 21, 26, and 30 weeks (n=5 in each group). Free radicals were detected by an electron spin resonance (ESR) method using LV tissue. The levels of messenger ribonucleic acid (mRNA) for VEGF, superoxide dismutase (SOD), and iNOS in myocardium were analyzed by reverse transcription (RT)-polymerase chain reaction (PCR). RESULTS: Free radicals consisting of superoxide families increased over time after aortic banding and were highest in the 30-week group. The SOD mRNA level decreased with the progression of hypertrophy and was inversely proportional to the free radicals level. As compared to the control, the level of mRNA for VEGF and iNOS was significantly increased in 18-and 21-week hypertrophied hearts, but significantly decreased in 26-and 30-week hearts. CONCLUSION: The increased level of free radicals with the decrease of VEGF and iNOS levels may contribute to the progression of the pressure-overload hypertrophied heart to the failing heart.

Effect of cannula shape on aortic wall and flow turbulence: hydrodynamic study during extracorporeal circulation in mock thoracic aorta.

This study was designed to analyze flow pattern, velocity, and strain on the aortic wall of a glass aortic model during extracorporeal circulation, and to elucidate the characteristics of flow pattern in four aortic cannulas. Different patterns of large vortices and helical flow were made by each cannula. The high-velocity flow (0.6 m/s) was observed in end-hole cannula, causing high strain rate tensor (0.3~0.4 without unit) on the aortic arch. In dispersion cannula, a decreased strain rate tensor (less than 0.1) was found on the outer curvature of the aortic arch. In Soft-flow cannula (3M Cardiovascular, Ann Arbor, MI, USA), further decreased flow velocity (0.2 m/s) and strain (less than 0.2) were observed. In Select 3D cannula (Medtronic, Inc., Minneapolis, MN, USA), a high strain (0.4~0.5) was observed along the inner curvature of the aortic arch. In conclusion, end-hole cannula should not be used in atherosclerotic aorta. Particular attention should be paid both for selection of cannulas and cannulation site based on this result.

[Left ventricular-right atrial communication resulting from infective endocarditis].

We report a rare case of acquired left ventricular-right atrial communication resulting from infective endocarditis. A 57-year-old male with aortic regurgitation due to infective endocarditis was referred to our hospital because of severe congestive heart failure. Preoperative transthoracic echocardiography showed aortic, mitral and tricuspid severe regurgitations. Intraoperative transesophageal echocardiography revealed left ventricular-right atrial shunt. The fistula was located at the atrioventricular membranous septum. The communication site from the left view was below the commissure between the right coronary cusp and non-coronary cusp, and from the right view was just above the tricuspid annulus of the septal leaflet. The fistula was closed directly with mattress suture and aortic valve replacement and both mitral and tricuspid ring annuloplasty were carried out simultaneously. The postoperative course was uneventful. It is important to inspect shunts carefully in echocardiography of infective endocarditis with massive regurgitations.