Observation of perpendicular exchange bias in an Ir-doped Fe2O3/Co ultrathin film system

The perpendicular exchange bias of an Fe₂O₃ thin film coupled with a ferromagnet was observed for the first time.

Volume-rendered 3D display of MR angiograms in the diagnosis of cerebral arteriovenous malformations

Purpose: To determine whether application of a volume-rendered display of 3D time-of-flight (TOF) MR angiography could assist the diagnosis of cerebral arteriovenous malformations (AVMs).

Material and Methods: Volume-rendered 3D images of postcontrast 3D time-of-flight MR angiography were compared with conventional angiograms in 12 patients. The correlation between the 3D images and the operative findings was also analyzed in 5 patients.

Results: The 3D-displayed images showed all of the feeders and drainers in 10 and 9 patients, respectively. In all patients, the nidus was three-dimensionally visualized. In 3 patients with hematomas, the relationship between the hematoma and the AVM was well demonstrated. The 3D images corresponded well with the operative findings in the 5 patients.

Conclusion: This method is of help in assessing the relationship between the components of an AVM as well as that between an AVM and an associated hematoma.

Intravenous thrombolysis for patients with reverse magnetic resonance angiography and diffusion-weighted imaging mismatch: SAMURAI and NCVC rt-PA Registries

BACKGROUND AND PURPOSE

The characteristics of reverse magnetic resonance angiography and diffusion-weighted imaging (MRA-DWI) mismatch (RMM), defined as a large DWI lesion in the absence of major artery occlusion (MAO), remain unknown, especially in patients treated with intravenous recombinant tissue plasminogen activator (rt-PA).

METHODS

Patients with stroke in the middle cerebral artery territory were included. Early ischaemic changes (EIC) were assessed with the Alberta Stroke Program Early CT Score on DWI (DWI-ASPECTS). All patients were divided into four groups based on the presence of MAO and a DWI-ASPECTS cut-off value of <7. RMM was defined as DWI-ASPECTS <7 without MAO. Clinical characteristics, symptomatic intracerebral hemorrhage (sICH) and favorable functional outcome (modified Rankin Scale score 0-2) at 90 days were compared amongst the four groups.

RESULTS

Of the 486 patients enrolled (167 women, median age 74 years, median initial National Institutes of Health Stroke Scale score 13), reverse MRA-DWI mismatch was observed in 24 (5%). Of the clinical characteristics, cardioembolism was the only factor that was independently associated with RMM [odds ratio (OR) 5.49, 95% confidence interval (CI) 1.25-24.1]. Multivariable analyses revealed that patients with RMM more commonly had sICH than those with DWI-ASPECTS ≥ 7 irrespective of the presence (OR 5.44, 95% CI 1.13-26.1) or absence (13.1, 2.07-83.3) of MAO, and they had a more favorable functional outcome than those with DWI-ASPECTS < 7 plus MAO (7.45, 2.39-23.2).

CONCLUSION

RMM was observed in 5% of patients treated with rt-PA and associated with cardioembolism. Patients with RMM may benefit from thrombolysis compared with those with EIC with MAO, although increment in the rate of sICH is a concern.

Run-up to participation in ATACH II in Japan

Intracerebral hemorrhage (ICH) is a major cause of morbidity and mortality in Japan. Seventeen Japanese institutions are participating in the Antihypertensive Treatment for Acute Cerebral Hemorrhage (ATACH) II Trial (ClinicalTrials.gov no. NCT01176565; UMIN 000006526). This phase III trial is designed to determine the therapeutic benefit of early intensive systolic blood pressure (BP) lowering for acute hypertension in ICH patients. This report explains the long run-up to reach the start of patient registration in ATACH II in Japan, including our preliminary study, a nationwide survey on antihypertensive treatment for acute ICH patients, a multicenter study for hyperacute BP lowering (the SAMURAI-ICH study), revision of the official Japanese label for intravenous nicardipine, and construction of the infrastructure for the trial.

Unconventional superconductivity of NpPd(5)Al(2)

The high quality single crystals of NpPd(5)Al(2) with the body-centered tetragonal structure were grown by the Pb flux method. NpPd(5)Al(2) was found to be the first Np-based heavy fermion superconductor with the relatively high critical temperature T(sc) = 4.9 K. The upper critical field H(c2) is large and highly anisotropic. Corresponding to the heavy electronic state, the initial slope of H(c2) is large, but H(c2) at low temperatures is suppressed by the magnetic field, indicating a strong Pauli paramagnetic effect and the first-order transition at H(c2). These results imply that NpPd(5)Al(2) is located at the proximity of the antiferromagnetic ordering, which might be hidden by the superconductivity. The d-wave superconductivity with a spin singlet state is most likely realized in NpPd(5)Al(2).

NMR evidence for higher-order multipole order parameters in NpO2

We report a microscopic investigation of multipolar order parameters in the ordered state of NpO2 conducted via 17O NMR on a single crystal. From the angular dependence of hyperfine fields at 17O nuclei, we have obtained clear evidence for the appearance of field-induced antiferro-octupolar as well as field-induced antiferro-dipolar moments below T0 = 26 K. We have also observed oscillatory spin-echo decay, which is well understood in terms of small electric field gradients created by antiferro-quadrupolar ordering. This reveals that the quadrupolar order parameter is directly observable by means of NMR. The present NMR studies provide definitive support for a proposed longitudinal triple-q type octupolar-quadrupolar ordering model for NpO2.

Direct observation of the microstructure in cluster glass compound U(2)IrSi(3)

We have examined the structure of a U(2)IrSi(3) compound exhibiting ferromagnetic cluster glass behaviour by means of electron diffraction observation and high-resolution electron microscopy. The structure of U(2)IrSi(3) has been proposed as a new one of the U(2)RuSi(3)-type with a short-range ordered double stacking sequence of the U(2)RuSi(3)-type structure along the c-axis, and long-range ordered atomic arrangements in the a-b plane. The calculated patterns reproduce the characteristic features of observed electron patterns well. The Fourier-filtered high-resolution image clearly exhibits a micro-domain structure, which is considered to relate directly to the origin of the observed cluster glass behaviour in U(2)IrSi(3).

Applications and Roles of Coil Embolization and/or Clipping in the Treatment of Cerebral Aneurysm

SUMMARY

We retrospectively analysed to demonstrate the selection of the treatment modality and its efficacy in our department. Subjects of the present study comprised patients in whom coil embolization was abandoned due to such reasons as broad neck, whom coil embolization was performed for residual aneurysm following incomplete clipping or recurrent cerebral aneurysm, whom coil embolization was performed after coil compaction, whom coil embolization and clipping were performed for the treatment of multiple cerebral aneurysms. In the treatment of cerebral aneurysm, selecting proper techniques by considering the characteristics of clipping and coil embolization is desirable. In other words, strategizing therapy by taking advantages of the merits of clipping and coil embolization is important.

Flow in a Tube with an Aneurysmal Sac: Effect of Aneurysm and Stent

Ruptured saccular aneurysms were severe condition for intracerebral Condition. And the cause for their rupture is not yet clear. In this study (I), since the configurations of aneurysms are considered to be a factor for the rupture of aneurysms, several shapes has been modeled using

Aspect ratio AR and inclination angle of saccular aneurysms. In vitro the parametric study has been conducted on the range of Reynolds Number in human blood flow for aneurismal models of AR=2.1 and 1.3 and q =90° and 70°, As results, it was con firme d that there are characteristic flow patterns with Reynolds Number, And that the aneurismal configuration has effects on the shear stress and pressure losses. II) The object of this paper is to study the effects of STENTS. We made the model of aneurysm and performed in vitro study in range of Reynolds number of human blood flows using three kinds of STENTS. As results, it was confirmed that flow pattern and pressure loss changes with the kinds of STENTS. This study aims the accumulation of data to predict the hazard of aneurysmal rupture by their shapes and STENTS.

Unilateral agenesis and hypoplasia of the internal carotid artery: a report of three cases

We report one patient with agenesis and two with hypoplasia of the internal carotid artery (ICA) from an angiographic series of 1275 consecutive patients. In all three patients, MRI and MR angiography were used to establish the anatomical situation; however, they may not clearly distinguish between hypoplasia and agenesis or acquired stenosis or occlusion of the ICA. In such cases, CT of the skull base may be obtained to clarify matters. In all patients, retrograde flow via a large posterior communicating artery was demonstrated. Single-photon emission computed tomography confirmed both the adequacy of cerebral perfusion and the preservation of vasomotor reactivity.

NMR evidence for triple-q multipole structure in NpO2

In order to elucidate the nature of the exotic ordered phase of NpO2 below T(0)=26 K, we have initiated the first 17O-NMR measurements on this system. From the 17O-NMR spectrum, the occurrence of two inequivalent oxygen sites has been confirmed below T0. It has also been shown that the characteristic features of the hyperfine interaction at the oxygen sites are well explained by invoking a hyperfine interaction with field-induced antiferromagnetic moments which appear as a result of the triple-q antiferroquadrupolar order. The NMR findings strongly support the occurrence of the longitudinal triple-q multipole structure in NpO2.

Volume-rendered 3D display of MR angiograms in the diagnosis of cerebral arteriovenous malformations

PURPOSE

To determine whether application of a volume-rendered display of 3D time-of-flight (TOF) MR angiography could assist the diagnosis of cerebral arteriovenous malformations (AVMs).

MATERIAL AND METHODS

Volume-rendered 3D images of postcontrast 3D time-of-flight MR angiography were compared with conventional angiograms in 12 patients. The correlation between the 3D images and the operative findings was also analyzed in 5 patients.

RESULTS

The 3D-displayed images showed all of the feeders and drainers in 10 and 9 patients, respectively. In all patients, the nidus was three-dimensionally visualized. In 3 patients with hematomas, the relationship between the hematoma and the AVM was well demonstrated. The 3D images corresponded well with the operative findings in the 5 patients.

CONCLUSION

This method is of help in assessing the relationship between the components of an AVM as well as that between an AVM and an associated hematoma.

Experience with the Norwood procedure without circulatory arrest

OBJECTIVE

We evaluated a new cardiopulmonary bypass technique that allowed complete avoidance of circulatory arrest and deep hypothermia in the Norwood procedure for hypoplastic left heart syndrome.

METHODS

A total of 10 patients were included in this study. The arterial line of the cardiopulmonary bypass circuit was divided in two in a Y shape; one branch was used for cerebral perfusion through the innominate artery and the other for lower body perfusion through the cannula inserted into the descending thoracic aorta. Moderate hypothermia (29 degrees C-31 degrees C rectal temperature) and high pump flow (150-180 mL. kg(-1). min(-1)) were used. A valveless conduit between the right ventricle and the pulmonary artery was used in 6 patients as an alternative pulmonary blood source to a conventional Blalock-Taussig shunt (n = 4).

RESULTS

Circulatory arrest was completely avoided throughout the operation in all cases, and no complications from the new cardiopulmonary bypass technique were seen. Early deaths occurred in 3 cases. Neurologic deficits were not seen among the survivors, and the postoperative course was stable and uneventful, including satisfactory renal function.

CONCLUSIONS

The Norwood procedure for hypoplastic left heart syndrome was successfully accomplished with complete avoidance of circulatory arrest by means of cerebral perfusion through the innominate artery combined with cannulation of the descending aorta. A conduit between the right ventricle and the pulmonary artery seems an excellent alternative pulmonary blood source, although right ventricular function needs to be carefully monitored.

Influence of glistenings on the optical quality of acrylic foldable intraocular lens

AIMS

To assess the influence of glistenings on the optical quality of acrylic foldable intraocular lens.

METHODS

Several degrees of glistenings in the optic were experimentally created by immersing the lens in water at 37 degrees C for 48 hours and then at 25 degrees C for 24 hours. Optical bench tests were carried out in water including measurements of spectral transmittance with the spectrophotometer, intensity of forward scattering using the integrating sphere photometer, modulation transfer function, and resolving power at various contrasts with and without the veiling glare light source.

RESULTS

Glistenings of 1+ to 4+ degrees were created, among which the 4+ glistenings seemed to be extremely intense and thought to be beyond the range of clinical settings. Clinically feasible level of glistenings, up to 3+, did not adversely influence spectral transmittance, scattering, modulation transfer function, and resolving power at various contrasts. The 4+ glistenings caused mild to moderate deteriorations of the optical quality of the lens.

CONCLUSION

The optical quality of the acrylic foldable intraocular lens is not significantly affected by the level of glistenings usually seen in the clinical setting.

Early and late results of total correction of congenital cardiac anomalies in infancy

OBJECTIVE

We evaluated long-term results of surgical correction of congenital cardiac anomalies in infancy.

METHODS

We reviewed cases of 856 patients who underwent complete correction of major cardiac anomalies in the first year of life during last 24 years at our institution, and analyzed results. Surgery involved ventricular septal defect (n = 453), tetralogy of Fallot (n = 92), atrioventricular canal defect (n = 93), and complete transposition of the great arteries (n = 218).

RESULTS

Operative mortality was 2.2% in ventricular septal defect, 0% in tetralogy of Fallot, 8.6% in atrioventricular canal defect, and 4.1% in complete transposition of the great arteries. Freedom from reoperation at 20 years was 96.5 +/- 2.0% and actuarial survival was 94.2 +/- 1.3% in ventricular septal defect. Freedom from reoperation at 15 years was 90.5 +/- 3.9% in tetralogy of Fallot and 86.6 +/- 4.4% in atrioventricular canal defect. Actuarial survival at 15 years was 97.8 +/- 1.6% in tetralogy of Fallot, 85.7 +/- 3.7% in atrioventricular canal defect, and 89.9 +/- 2.2% in complete transposition of the great arteries. Actuarial survival in complete transposition of the great arteries was significantly better in arterial than in atrial switch operations.

CONCLUSIONS

Total correction of ventricular septal defect, tetralogy of Fallot, atrioventricular canal defect, and complete transposition of the great arteries in infancy was conducted safely, but the incidence of reoperation in late follow-up must be reduced.

[Repeated vertebrobasilar ischemic stroke caused by an intracranial vertebral artery dissection not detected on the initial angiogram: a case report]

Spontaneous dissection of the intracranial vertebral artery has been increasingly recognized as a cause of vertebrobasilar ischemic stroke. However, little is known about its natural history and clinical course. The authors report a young patient with repeated cerebral infarction in the posterior cerebral circulation caused by dissection of the vertebral artery, which was not detected on the first angiogram. The otherwise healthy 22-year-old male suddenly developed visual disturbance. Neuroradiological examination revealed right occipital infarction, but cerebral aniography revealed no caliber change or other pathological findings. He was treated with antiplatelet therapy. Two years later, he suffered vertigo, nausea, and dysarthria due to newly developed left cerebellar and medullary infarction. Cerebral angiography revealed left vertebral artery occlusion. T1-weighted MR image demonstrated Gadlinium-enhanced intramural hematoma in the occluded left vertebral artery, which was compatible to the arterial dissection. The present case argues serial neuroimaging studies especially in young patients with vertebrobasilar stroke in order to rule out the arterial dissection, even if initial angiography failed to demonstrate any radiographical evidence.

Mass spectrometry for on-line monitoring of perfluoro compounds using Li+ ion attachment techniques

Ion attachment mass spectrometry is being developed for continuous measurement of perfluoro compounds (PFCs) found in the atmosphere as a result of semiconductor manufacturing processes. Studies were made on 5 greenhouse gases, CF4, CHF3, C2F6, SF6, and c-C4F8, to develop improved methods for PFC analysis, particularly at levels found in the atmosphere (the parts-per-billion concentration range). The results demonstrate the feasibility of performing real-time measurements of the trace amounts of PFCs encountered in process facilities by generating adduct ions from Li+ ion attachment. The identification and detection of c-C4F8 is described as an example of the utility of this new method.

[Surgical management for an unruptured cerebral aneurysm accompanied by anti-phospholipid antibody syndrome: a case report]

Anti-phospholipid antibody syndrome(APS) is characterized by the presence of antibodies to phospholipids and various symptoms including those derived from thrombosis. APS has been shown to be frequently accompanied by multiple and recurrent cerebral ischemic lesions, suggesting that APS may play a critical role in developing cerebral ischemia of unknown etiology. Here, we present a case with an unruptured cerebral aneurysm accompanied by a severe stenosis of the middle cerebral artery as a manifestation of APS. The aneurysm was successfully treated surgically employing the following precaution to prevent potential damage on the fragile ischemic brain: preoperative administration of anticonvulsant, intermittent brain retraction, intraoperative SEP monitoring, and postoperative administration of anticoagulant. Our experience suggests that unruptured cerebral aneurysms accompanied by APS could be safely treated by strict paraoperative management.

[Current status and controversies on the management of cerebral main trunk occlusion]

Management of the cerebral main trunk occlusive disease has proceeded during last decade owing to remarkable progress of diagnostic and interventional neuroradiology. Several large clinical trials have established treatment guidelines in most of stroke management. Concerning cerebral main trunk occlusion, management of acute embolic ischemia and surgical indication for chronic carotid artery occlusion has still remained unsettled. In this article, outline of previous discussion and current status and controversies are reviewed.

[The surgical treatment of congenital valve disease]

The clinical results after surgical treatment of congenital valve disease have improved due to the use of several recently developed techniques. The replacement of tendinous cords using E-PTFE sutures has allowed the indications for the repair of mitral valve prolapse to be extended. The Ross procedure has made it possible to replace the aortic valve associated with small aortic annulus. However, replacement with a prosthetic valve remains the only option if repair is not possible or fails. Prosthetic valve replacement in the pediatric age-group remains challenging in patients with a small valve annulus. A number of techniques can be employed in such cases, including enlargement of the aortic annulus and translocation of the prosthetic valve in the left atrium, although there are limits on the size of the prosthesis. Further improvement of surgical techniques is necessary, along with the development of prosthetic valves using more nearly physiological materials.

Successful staged-Fontan operation in a patient with ectopia cordis

Ectopia cordis is a very rare and often fatal disease. We report a successful surgery case of thoracoabdominal ectopia cordis with univentricular heart. This patient underwent a three-stage Fontan procedure, a right-modified Blalock-Taussig shunt at the age of 1 month, bidirectional Glenn shunt and pulmonary arterioplasty at 2 years 8 months, and finally a total cavopulmonary connection at 4 years. This patient was discharged from the hospital in good condition and has been doing well since. Thus, ectopia cordis is not a contraindication for a Fontan operation.

Asymmetric synthesis and determination of the absolute configuration of FK584, an agent for the treatment of overactive detrusor

FK584[(-)-N-tert-butyl-4,4-diphenyl-2-cyclopentenylamine hydrochloride, (-)-4-HCl], a potential candidate for the treatment of overactive detrusor, was synthesized in a 4-step approach starting with Sharpless oxidation of cyclopentenol 6 (kinetic resolution). This epoxidation is a rare case in that the empirical rule does not work. Regio- and stereoselective introduction of tert-butylamine to the obtained epoxycyclopentanol 5 and subsequent conversion of the resulting diol to an olefin completed the synthesis. The absolute configuration of FK584 was determined to be S by X-ray crystallographic analysis of the salt of S-(+)-mandelic acid.

[Patching of the raw surface of the posterior right ventricular wall in Ross procedure to prevent bleeding and to confirm anastomosis of the conduit]

An 8-year-old boy underwent Ross procedure to repair aortic regurgitation and subaortic stenosis. In reconstruction of the right ventricular outflow tract, the raw surface of the right ventricular posterior wall was covered with autologous pericardial patch to prevent bleeding and to confirm the anastomosis of the pulmonary tract conduit made of expanded polytetrafluoroethylene. Bleeding from the posterior wall was absent and he led uneventful postoperative course. Same technique was used in 4 other patients, and satisfactory results were obtained. This technique, first reported from India, seems very useful in Ross procedure.

Mitral valve replacement using bileaflet mechanical prosthetic valve in the first year of life

OBJECTIVE

The operative management and long term outcome of mitral valve replacement in infancy remain a therapeutic challenge. The selection of a prosthetic valve for this particular age group might affect the clinical outcome. Here we present our experience of mitral valve replacement in 6 infants using small bileaflet mechanical prosthetic valves.

METHODS

Between January 1994 and August 1997, 6 infants (their age ranged from 3 months to 11 months, and their body weight from 2978 g to 7403 g) underwent mitral valve replacement using a mechanical valve prosthesis (16 mm CarboMedics prosthetic valve in 5, and 17 mm St. Jude Medical prosthetic valve Hemodynamic Plus in 1). The preoperative morphological features of the mitral valve were stenosis in 1, regurgitation in 3, and a combination of these in 2. The prosthesis was fixed at the annulus in 3, and at the supra-annular position in 3. Anticoagulation was performed using warfarin.

RESULTS

There was no operative mortality. Postoperative catheterization revealed an acceptable wedge pressure in the pulmonary arteries, ranging from 10 to 12 mmHg. During the mean follow-up period of 36 months, late death due to residual pulmonary hypertension occurred in 1 patient at 10 months after surgery. Excluding this patient, all remaining patients are doing well with no need for repeated operation with no thromboembolic complication. The actuarial survival rate and the reoperation free rate at 70 months are 83 +/- 15% and 100%, respectively.

CONCLUSION

Mitral valve replacement using a small size bileaflet mechanical prosthetic valves in infancy can be performed with low operative mortality and with satisfactory mid-term results.

Cloning and characterization of a human brain Na(+)-independent transporter for small neutral amino acids that transports D-serine with high affinity

We isolated a cDNA for the human homologue of system asc transporter Asc-1 from human brain. The encoded protein designated as hAsc-1 (human Asc-1) exhibited 91 % sequence identity to mouse Asc-1. Consistent with mouse Asc-1, hAsc-1 required 4F2 heavy chain for its functional expression in Xenopus oocytes. hAsc-1 exhibited the properties of amino acid transport system asc which transports small neutral amino acids in a Na(+)-independent manner. hAsc-1 transported D-serine at high affinity with a K(m) value of 22.8 microM. In brain, 2.0 kb mRNA was highly expressed. hAsc-1 gene was mapped to human chromosome 19, region q12-q13.1. Because of the high-affinity transport with the K(m) value close to the physiological concentration of D-serine, together with the high levels of expression in brain, hAsc-1 is proposed to play significant roles in the D-serine mobilization in brain.

Clinicopathological study of intracranial fusiform and dolichoectatic aneurysms : insight on the mechanism of growth

BACKGROUND AND PURPOSE

Intracranial fusiform aneurysms can be divided into 2 clinically different subtypes: acute dissecting aneurysms and chronic fusiform or dolichoectatic aneurysms. Of these 2, the natural history and growth mechanism of chronic fusiform aneurysms remains unknown.

METHODS

A consecutive series of 16 patients with chronic fusiform aneurysms was studied retrospectively to clarify patient clinical and neuroradiological features. Aneurysm tissues were obtained from 8 cases and were examined to identify histological features that could correspond to the radiological findings.

RESULTS

Four histological features were found: (1) fragmentation of internal elastic lamina (IEL), (2) neoangiogenesis within the thickened intima, (3) intramural hemorrhage (IMH) and thrombus formation, and (4) repetitive intramural hemorrhages from the newly formed vessels within thrombus. IEL fragmentation was found in all cases, which suggests that this change may be one of the earliest processes of aneurysm formation. MRI or CT detected IMH, and marked contrast enhancement of the inside of the aneurysm wall (CEI) on MRI corresponded well with intimal thickening. Eight of 9 symptomatic cases but none of 7 asymptomatic cases presented with both radiological features.

CONCLUSIONS

Data suggest that chronic fusiform aneurysms are progressive lesions that start with IEL fragmentation. Formation of IMH seems to be a critical event necessary for lesions to become symptomatic and progress, and this can be monitored on MRI. Knowledge of this possible mechanism of progression and corresponding MRI characteristics could help determine timing of surgical intervention.

[Efficacy of intravenous administration of atrial natriuretic peptide after cardiac surgery in neonates and infants]

Intravenous infusion of alpha-human atrial natriuretic polypeptide (hANP) and furosemide was performed in 12 patients (4: TGA, 3: univentricular heart, 3: HLHS, 2: VSD) after cardiopulmonary bypass. Their mean age at the operation was 68 days (6 patients in neonate), the mean body weight was 3.3 kg. All patients were treated with nitroglycerin in dose of 2 micrograms/kg/min and chlorpromazine in dose of 2.8 micrograms/kg/min and catecholamine in mean dose of 6.5 micrograms/kg/min. The criteria of indication for hANP was poor effect of furosemide alone. The hANP was given for 6-144 hours in dose of 0.1-0.2 microgram/kg/min. With the hANP and furosemide infusion, urine volume increased from 85.0 +/- 14.2 ml/kg/day to 107.9 +/- 25.3 ml/kg/day (p < 0.05), whereas the systemic arterial pressure, the central venous pressure and the renal function were unchanged. We conclude that the combination of the hANP and the furosemide is very effective in neonates and infants.

Norwood procedure without circulatory arrest

In the Norwood procedure for hypoplastic left heart yndrome, the distal descending thoracic aorta was cannulated just superior to the diaphragm through median sternotomy. In combination with cerebral perfusion through the graft anastomosed to the innominate artery, which was used as a systemic-to-pulmonary shunt later, this technique enabled us to completely avoid circulatory arrest and deep hypothermia throughout the operation.

Clinical results of mitral valve repair by reconstructing artificial chordae tendineae in children

OBJECTIVE

There are an increasing number of reports concerning mitral valve repair by reconstructing the chordae tendineae with the use of expanded polytetrafluoroethylene sutures in adults. However, little information is available about application or results of this technique in children.

METHODS

Between January 1995 and December 1997, 16 children who had from moderate to severe mitral regurgitation mainly as the result of a prolapse of the anterior leaflet (age range, 5 months-12.8 years) underwent mitral valve repair by reconstruction of artificial chordae. Either unilateral or bilateral Kay-Reed annuloplasty was also performed to correct annular dilatation in all patients.

RESULTS

No operative death or morbidity was observed. Before discharge, immediate postoperative echocardiography showed less than trivial mitral regurgitation in all patients. The follow-up was complete in all cases by a clinical examination and serial echocardiograms, and the median follow-up period was 14.8 months (range, 1.3-26.4 months). There were no valve-related events during the entire follow-up period. The degree of mitral regurgitation, estimated by echocardiography performed at recent follow-up period, was none in 5 patients, trivial in 10 patients, and mild in 1 patient. The diastolic and systolic dimensions of the left ventricle decreased and were 95.0% and 96.2% of the normal values, respectively.

CONCLUSIONS

Although further investigations and long-term results are still called for, mitral valve repair by reconstruction of the artificial chordae was found to be safe and effective even in infants and children.