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.

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.

[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.

Posteromedial papillary muscle rupture due to squeezing of the left anterior descending coronary artery.

An unusual case of posteromedial papillary muscle (PPM) rupture due to isolated left anterior descending (LAD) artery ischaemia, associated with severe myocardial bridge contraction, is presented. The unusual blood supply to the PPM was associated with its apical origin and apex-forming LAD.

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.

Simultaneous repair of multiple aortic aneurysms: be courageous in minimally invasive era.

The simultaneous treatment of multiple ruptured aortic aneurysms is a surgical challenge. Here we present a case of a 53-year-old woman with Marfan syndrome who had annuloaortic ectasia of 4.2 cm and a thoracoabdominal aortic aneurysm of 6 cm. The patient developed acute aortic dissection complicated with cardiac tamponade and thoracoabdominal aortic rupture. An emergency operation, which included a Bentall operation, total arch replacement, and thoracoabdominal repair, was performed for 2 remote aneurysms. By paying particular attention to organ perfusion, a single-stage operation was successfully performed and the patient fully recovered.

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.

Management of infective endocarditis with cerebral complications.

PURPOSE: Management of patients with infective endocarditis complicated by neurological deficits is challenging. No clear management guidelines have been defined, and the timing of surgery remains controversial. The purpose of this study was to evaluate our management algorithm. METHODS: Thirty-eight adult patients with left-sided infective endocarditis undergoing valve surgery were analyzed. Before the operation, enhanced brain computed tomography (CT) was performed to rule out a cerebral complication. Pre and postoperative data were retrospectively reviewed to clarify whether our algorithm was effective. Sixteen patients having neurological complication (CVC group) were compared with 22 patients without neurological complication. RESULTS: Age, sex, New York Heart Association (NYHA) functional class, affected valve and pathogens were not different between two groups. Mean interval from the onset of neurological dysfunction to cardiac operation was 27.8 ± 27.8 days (median 23 days). Of the 16 CVC group patients, 12 experienced cerebral infarction. Mass effects were seen in 3 patients, with 1 of these 3 patients died following aneurysm rupture. Mycotic aneurysm was detected in 4 patients, with 3 undergoing successful staged operations. Mortality and postoperative neurological exacerbation in CVC group was 6.3% (1 patient). Most patients who fulfilled the algorithm showed good outcomes. CONCLUSIONS: Our suggested management algorithm for infective endocarditis appears effective.

Hydrogen-bonding effect on spin-center transfer of tetrathiafulvalene-linked 6-oxophenalenoxyl evaluated using temperature-dependent cyclic voltammetry and theoretical calculations.

The stable tetrathiafulvalene (TTF)-linked 6-oxophenalenoxyl neutral radical exhibits a spin-center transfer with a continuous color change in solution caused by an intramolecular electron transfer, which is dependent on solvent and temperature. Cyclic voltammetry measurements showed that addition of 2,2,2-trifluoroethanol (TFE) to a benzonitrile solution of the neutral radical induces a redox potential shift that is favorable for the spin-center transfer. Temperature-dependent cyclic voltammetry of the neutral radical using a novel low-temperature electrochemical cell demonstrated that the redox potentials change with decreasing temperature in a 199:1 CH2Cl2/TFE mixed solvent. Furthermore, theoretical calculation revealed that the energy levels of the frontier molecular orbitals involved in the spin-center transfer are lowered by the hydrogen-bonding interaction of TFE with the neutral radical. These results indicate that the hydrogen-bonding effect is a key factor for the occurrence of the spin-center transfer of TTF-linked 6-oxophenalenoxyl.

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.

Infective endocarditis with cerebrovascular complications: timing of surgical intervention.

Management of infective endocarditis (IE) with cerebrovascular complications is difficult due to absence of concrete evidence. These patients usually have multiple neurological deficits and the optimal timing for cardiac operation remains controversial. The aims of this study were to present cases and discuss the treatment options for IE with cerebrovascular complications. From 1998 to 2010, 51 patients underwent operations for IE at our institution. From a review of medical records, 10 patients (19.6%) with preoperative neurological complications were identified. Data on these 10 patients were analysed. Cerebrovascular complications included cerebral infarction (n = 4, 40.0%), mycotic aneurysm (n = 1, 10.0%), mycotic aneurysm plus cerebral infarction (n = 3, 30.0%), meningitis (n = 1, 10.0%) and mycotic aneurysm with cerebral haemorrhage plus meningitis (n = 1, 10.0%). Of 5 patients having mycotic aneurysms, 3 underwent clipping before cardiac operations. The mean interval from craniotomy to cardiac operations was 26.7 ± 21.8 days. A cardiac operation was performed initially on seven patients. The mean interval from the onset of neurological deficit to cardiac operation was 7.4 ± 9.8 days. The mortality rate was 10.0%. Postoperative deterioration was not observed. Management of IE with cerebrovascular complications should be based on case-by-case multidisciplinary assessment of potential risks and benefits of intracranial and cardiac operations.

Electronic stabilization effect of a spin-delocalized neutral radical: synthesis of an 8-cyano-6-oxophenalenoxyl derivative and quantitative evaluation of the electronic spin structure in terms of resonance structures.

A new 2,5-di-tert-butyl-6-oxophenalenoxyl (6OPO) derivative with a cyano group at the 8-position, where a large spin density resides, has been synthesized. This neutral radical exhibits high stability in the solid state in air despite the low steric protection on the 8-position; the stability is comparable to that of a corresponding 8-tert-butylated 6OPO derivative. EPR/(1)H-ENDOR/TRIPLE (electron paramagnetic resonance/(1)H-electron-nuclear double resonance/TRIPLE) spectroscopy and cyclic voltammetry showed an extended spin delocalization on the cyano group and a significant increase in electron-accepting ability relative to that of the 8-tert-butylated 6OPO derivative. DFT calculations indicated the extension of a singly occupied molecular orbital (SOMO) onto the cyano group and the lower-lying SOMO and LUMO in comparison with those of the 8-tert-butylated 6OPO derivative, which was consistent with experimental results. Furthermore, the extended nature of π conjugation onto the cyano group was quantitatively evaluated by calculating the contributing weights of resonance structures in terms of a molecular orbital (MO)-based valence-bond (VB) method. Herein, the synthesis and physical properties of the 8-cyano-6OPO derivative are described, emphasizing that the high stability arises from the electronic effect of the cyano group. Also, the usefulness of the quantitative resonance structure analysis is shown.

Improved outcome of surgical pulmonary embolectomy by aggressive intervention for critically ill patients.

BACKGROUND: Acute massive pulmonary thromboembolism is a life-threatening disorder, and prompt treatment is necessary. We analyzed the outcome of pulmonary embolectomy for massive pulmonary embolism. METHODS: Nineteen patients who underwent pulmonary embolectomy were retrospectively investigated. Average age of patients was 59 years, and 79% were female. Most patients had massive or submassive pulmonary thromboemboli dislodging into the main pulmonary trunk or bilateral main pulmonary arteries. Hemodynamics of most patients were unstable. Two patients required percutaneous cardiopulmonary support before embolectomy, and 4 required cardiopulmonary resuscitation. In 6 patients, thrombolysis was ineffective. RESULTS: All patients underwent emergent pulmonary embolectomy. Operative mortality was 5.3%. No patients exhibited newly developed neurologic damage. Ten-year survival rate was 83.5% ± 8.7%. CONCLUSIONS: Pulmonary embolectomy saves critically ill patients having acute massive pulmonary thromboembolism. We must evaluate pulmonary embolism patients with an algorithm that includes surgical embolectomy as one of several therapeutic options.

Enucleation of calcium core and in-situ valve replacement for massive posterior mitral annular calcification.

A 67-year-old female was admitted to our hospital for surgical treatment of the aortic and mitral valvular disease. She had chronic renal failure and dialysis was started 13 years previously. A diagnosis of severe aortic stenosis and regurgitation with severe mitral stenosis was made, and she underwent aortic valve and mitral valve replacement. Because mitral annular calcification had deeply invaded into the subvalvular region, enucleation of calcified core was performed using the ultrasonic aspiration system. The posterior mitral annulus was reconstructed using equine pericardium and aortic and mitral valve replacement was performed. The postoperative course was uneventful.

Open door approach by partial sternotomy and sterno-costo-chondroplasty for annuloaortic ectasia with pectus excavatum.

A 32-year-old female patient with Marfan syndrome was admitted for repair of annuloaortic ectasia and severe pectus excavatum. Because the chest cage deformity was severe, concomitant reparative surgery of the chest wall was performed. Partial median sternotomy and left second-fifth rib division was made to obtain good surgical field. The patient underwent valve-sparing aortic root remodeling successfully. After complete neutralization of heparin, additional division of the right ribs was performed and each rib and the sternum was reshaped. Pectus excavatum was completely repaired by this method. We believe this approach is efficacious for intracardiac repair with severe pectus excavatum.

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.