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.

Synthesis of oligosaccharide with controlled sequence

A simple method for the synthesis of alternate heteropolysaccharide was investigated. Two types of modified glucose were combined into a cellobiose-type disaccharide monomer having only acetyl groups except a free hydroxyl group at C-3'. Polycondensation of this monomer, using stannic tetrachloride as catalyst, easily gave a novel copolysaccharide having regularly alternating 1,3-beta and 1,4-beta linkages.

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.

[Clinical laboratory data and reference intervals standardized in Fukuoka]

In Fukuoka whose population is approximately five million inhabitants, surveys on the accuracy of laboratory data have been performed by the Fukuoka Prefecture Medical Association for the last 30 years. We have been attempting to evaluate the data for routine use since 1988, and it has become possible to share laboratory data between all institutions in Fukuoka prefectures. As a result, reference intervals for 23 clinical chemistry analytes were established in 1995, to which were added in 1996 five serum protein constituents that have been utilized for clinical examinations. Methods for documentations and monitorings the data obtained in the prefecture were also established, standardization of the above analytes extended to 97% of the institutions in the prefecture. Results for 14 of the 23 clinical chemistry analytes have become highly reliable and clinically useful as differences between institutions in terms of results have narrowed. Standardization of other analytes is now in progress.

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.

Standardization of Laboratory Data and Establishment of Reference Intervals in the Fukuoka Prefecture: A Japanese Perspective

Standardization of 22 clinical chemistry analytes and five serum protein constituents has been performed in the Fukuoka Prefecture, which has a population of approximately five million. The standardization project was established to determine reference intervals for these analytes by educating physicians, medical technologists and staff of medical institutions, and by daily or monthly monitoring the use of common control samples through e-mail. Standardization extended to 97% of the institutions in the prefecture. Results for 14 of the 22 clinical chemistry analytes have become highly reliable and differences between institutions decreased. Standardization of other analytes is now in progress. Regional collaboration based on international guidelines led to a significant improvement in interlaboratory comparability. Areas where further improvements are needed have been identified.

[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.

Successful implantation of a bipolar epicardial lead and an autocapture pacemaker in a low-body-weight infant with congenital atrioventricular block: report of a case

A permanent pacemaker system was successfully implanted into a low-body-weight infant with congenital atrioventricular (AV) block, using a bipolar epicardial CapSure Epi lead and an autocaptured Pacesetter Solus-micro VVIR pacemaker. The calculated life span of the pacemaker generator is 5 years with a heart rate of 120/min and an output of 1.2 V (0.31 ms), and fortunately, its threshold was autocaptured. Thus, we can conclude that the combination of a steroid-eluted bipolar epicardial lead and the smallest possible autocaptured pacemaker generator is most suitable for a neonate or young infant.

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.

Surgical treatment of tricuspid regurgitation caused by Löffler's endocarditis

A 25-year-old man with a history of bone-marrow-transplantation for the treatment of Löffler's endocarditis underwent surgery for massive tricuspid regurgitation with paroxysmal atrial flutter. Dense fibrosis in the right ventricular endocardium with complete obliteration of the apex was seen intraoperatively, and the right ventricular cavity was diminished. Annular dilatation of the tricuspid valve and entrapment of the posterior leaflet to the endocardial fibrosis were also seen. Annuloplication at the posterior leaflet was performed. In addition, the right atrial free wall was widely resected and the septal and inferior vena cava-tricuspid valve isthmi were cryoablated for the treatment of atrial flutter. Postoperative catheterization revealed rather high right ventricular end-diastolic pressure. However, tricuspid regurgitation disappeared with the increased cardiac output. Atrial flutter could not be induced by repetitive stimulation in the postoperative electrophysiological examination.

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.

Fate of atrial flap used in repair of total anomalous pulmonary venous connection

Histological changes in the right atrial flap used in repair of total anomalous pulmonary venous connection were observed when the patient underwent repair of peripheral pulmonary venous stenosis after two months. The flap, 35 mm in length and 15 mm in width, was thin and soft. Microscopically, endocardium and myocardium were preserved well, with only moderate thickening of the epicardium. We can anticipate the viability of the right atrial flap, but care should be taken to keep blood supply to the flap intact.

[Descending aorta perfusion through median sternotomy in primary repair of aortic interruption complex]

Circulatory arrest is frequently used in aortic arch reconstruction in pediatric cardiac surgery. However, risks of postoperative acute renal failure and neurological deficit can not be ignored. We performed primary repair of aortic interruption in one-month old girl. After commencing extracorporeal circulation with bicaval venous cannulae and with arterial cannulae into the pulmonary trunk and the innominate artery, the descending aorta was cannulated just superior to the diaphragm. The cannula in the pulmonary trunk was then removed. Arch reconstruction and closure of the ventricular septal defect were performed with continuous perfusion to the brain and the lower body. The extracorporeal circulation time and the aortic cross-clamp time were 117 min and 21 min, respectively. Postoperative renal function was excellent, and there was no finding of neurological deficit. Cannulation of the descending aorta is a simple and useful technique with safety, in arch reconstruction in infants.

[Clinical results of mitral valve surgery in children]

The clinical results of mitral valve surgery in children were evaluated. Fifty children (age ranged between 1 month and 12 years) with mitral valve regurgitation have undergone valve surgery with low operative mortality (2%). Valve plasty using several techniques including annuloplasty have been performed with quite high success rate (92%), while valve replacement was required in four patients who had the prolapse of the anterior mitral leaflet (8%). Reoperation was required in 5 patients (10%), and there were 4 late deaths. Introduction of the reconstructive technique of the chordae tendinae using artificial chordae resulted 100% success rate of mitral repair for the prolapse of the anterior mitral leaflet without death and reoperation. The reoperation free rate and the actuarial survival rate at 15 years of the patients with mitral regurgitation were 70 +/- 12% and 85 +/- 7%, respectively. In ten patients with mitral valve stenosis (age ranged between 1 month and 5 years), 5 patients required valve replacement (50%), and 2 patients died (20%). The clinical results of the surgery for the mitral stenosis were still unsatisfactory, and the reoperation free rate at 2 years was 42 +/- 30% and the actuarial survival rate at 13 years were 32 +/- 18%.

Mixed type of total anomalous pulmonary venous connection

BACKGROUND

The mixed type of total anomalous pulmonary venous connection is a rare condition in which some diagnostic and surgical problems still remain to be solved.

METHODS

In 9 patients a single pulmonary vein was connected to the systemic vein at a site different from the drainage site of the confluence of three other pulmonary veins. In 2 other patients, four pulmonary veins made a confluence which had two drainage sites. Correct diagnosis was made in all 7 patients who received cardiac catheterization but only in 5 of the 9 patients by color Doppler echocardiography. Total correction was performed in 3 patients and the single anomalous pulmonary vein was left uncorrected in 8 other patients.

RESULTS

There were two in-hospital deaths. Seven patients with a single residual anomalous pulmonary vein have been in good condition without clinical symptoms of congestive heart failure or pulmonary hypertension.

CONCLUSIONS

Diagnosis of mixed type of total anomalous pulmonary venous correction by echocardiography is sometimes difficult. When a mixed type is suspected, cardiac catheterization is recommended if the condition of the patient permits it. A single anomalous pulmonary vein may be left uncorrected without serious complications, but close observation is needed to prevent congestive heart failure and pulmonary vascular obstructive disease.

[Questionnaire of cryopreserved allograft valves in Kyushu and Yamaguchi area]

Japanese Society of Cryopreserved Thoracic Tissue Implantation was recently set up. Cryopreserved allograft valves are about to pervade in Japan. To clarify the interest, demands and supply of cryopreserved allograft valve in the area of Kyushu and Yamaguchi, we performed questionnaire investigation regarding this issue. Collection rate of this questionnaire was 87.5% (35/40 hospitals). Ninety-seven percent of the hospitals answered that they were interested in cryopreserved allograft. Ninety-four percent of the hospitals answered that they did not ethically hesitate to use cryopreserved allograft. Ninety-one percent of the hospitals hoped to perform cardiac surgery using allograft aortic valve if allograft is available. With respect to securing donors of allograft, two-third of the hospitals did not decide whether they could be involved in obtaining donors of allograft. As the number of the cadaver kidney donors is about 20 per year in the area of Kyushu and Yamaguchi, shortage of donors of allograft valve is anticipated.

Subaortic stenosis caused by anomalous papillary muscle of the mitral valve

We report on a rare case of subaortic stenosis caused by an anomalous posteromedial papillary muscle inserting directly into the anterior mitral leaflet, which had muscular extension to the subaortic region. Resection of the muscular extension alone was ineffective. A second operation including entire resection of the anomalous papillary muscle and mitral valve replacement resulted in successful relief of the obstruction. Microscopic findings of the resected tissue were compatible with those of hypertrophic cardiomyopathy.

[Staged repair for bilateral ductus arteriosus with pulmonary atresia and non-confluent pulmonary artery--a case report]

Staged operation was successfully performed in an infant with bilateral ductus arteriosus, and absence pulmonary artery. The first stage operation was performed at 2 months old of age. The left pulmonary artery was reconstructed using an equine pericardial roll sized 10 mm in diameter, and a 5 mm Dacron graft was anastomosed between the left subclavian artery and the roll as an aortopulmonary shunt. In the second stage, the same procedure was done on the right side at eight months of age. In the last stage, the patient underwent Rastelli procedure at 2 years old of age. The central pulmonary artery was created with a ring forced EPTFE graft above the ascending aorta, and a Carpentier-Edwards valved conduit (14 mm) was anastomosed between the right ventricle and the EPTFE graft. Post operative course was uneventful. We consider that the staged procedure including the pulmonary artery reconstruction and the aortopulmonary shunt on both sides is recommended in the case of absent central pulmonary artery in infant.

Postoperative cardiac rhythms with superior-septal approach and lateral approach to the mitral valve

BACKGROUND

The superior-septal approach provides an excellent view of the mitral valve and therefore has received considerable interest. However, the safety of this approach is controversial because it requires division of the sinus node artery in most cases.

METHODS

Postoperative cardiac rhythms were analyzed in 152 consecutive patients who underwent mitral valve procedures between January 1992 and February 1995 with a conventional right lateral left atriotomy (group 1, n = 69) or the superior-septal approach (group 2, n = 83). Follow-up ranged from 2 to 38 months, and the mean follow-up was 16.1 months in group 1 and 13.8 months in group 2.

RESULTS

The mortality rate was similar in the two groups (1.4% in group 1 and 1.2% in group 2), and the causes of death were not related to the left atriotomy. At discharge, 96% of the patients in group 1 who were in sinus rhythm preoperatively and 78% of those in group 2 remained in sinus rhythm. At the last follow-up, 88% of these patients in group 1 and 83% in group 2 remained in sinus rhythm. Among the patients in atrial fibrillation or junctional rhythm before operation, 12% in group 1 and 11% in group 2 had regained sinus rhythm at the last follow-up. There were no significant differences in these values.

CONCLUSIONS

Although the incidence of dysrhythmias was higher with the superior-septal approach in the early postoperative period, this approach provides an excellent operative view of the mitral valve and similar results in terms of late postoperative cardiac rhythms as the right lateral left atriotomy.

Selective cerebral perfusion technique during aortic arch repair in neonates

We describe selective cerebral perfusion techniques for repair of the aortic arch in neonates. These techniques may help protect the brain from ischemic injury caused by a cessation of cerebral perfusion for aortic arch reconstruction in patients with hypoplastic left heart syndrome or interrupted aortic arch.

[Surgical results of valvuloplasty for common atrioventricular valve regurgitation in single ventricle]

From 1988 through 1994, 18 patients who had common atrioventricular valve regurgitation associated with single ventricle underwent valvuloplasty. All patients had isomerism heart (right isomerism: 16, left isomerism: 2). The preoperative degree of regurgitation was 3.3 +/- 0.4 (Sellers). Valvuloplasty was performed by two different procedures. Semi-circular annuloplasty was used in nine patients. Dividing the common atrioventricular valve orifice into two parts (bivalvation) with or without annuloplasty was used in nine. The concomitant procedures varied: three patients underwent systemic pulmonary shunt, two underwent repair of total anomalous pulmonary venous drainage, one underwent pulmonary arterial banding, five underwent bidirectional Glenn, shunt, and four underwent Fontan operation. One early death and three late deaths have occurred. The early postoperative degree of regurgitation was reduced to 1.3 +/- 1.0. In nine patients, however, the degree of regurgitation increased late postoperatively. Seven patients were reoperated on because of regurgitation: three patients had valve replacement and four had reannuloplasty. Increased incidence of deterioration of regurgitation in late period was seen in patients under 2 years old and those receiving a concomitant Blalock shunt. Lower event-free rate after 2 years was seen in patients with double inlet right or indeterminate ventricle and those underwent the annuloplasty alone. We conclude that the dividing common atrioventricular valve orifice into two parts with annuloplasty could effectively reduce the regurgitation in most patients with isomerism heart, and the concomitant ventricular unloading operation seems to offer promise for improving long-term results.

[Postoperative pulmonary stenosis after arterial switch operation, comparison in three methods of pulmonary reconstruction: modified Pacifico, autologous pericardial patch, and equine pericardial patch]

To prevent postoperative pulmonary stenosis in arterial switch operation for transposition of the great arteries, pulmonary reconstruction without patch augmentation (modified Pacifico method: Pa-group) and reconstruction using W-shaped fresh autologous pericardium (AW-group) were introduced instead of the former method using equine pericardium (XW-group). Postoperative pulmonary stenosis (RV-PA pressure gradient greater than 30 mmHg) was not seen among the 17 cases in the Pa-group (0%), and was seen in 2/14 (14.3%) in the AW-group and in 4/14 (29%) in the XW-group. Progressive increase in pressure gradient was seen in the XW-group in the midterm cardiac catheterization (p < 0.01), but such tendency was not observed in the Pa-group and the AW-group. Sectional area at the pulmonary valve ring, at the anastomotic site in the main pulmonary artery, and at the pulmonary branches just distal to the bifurcation, standardized by the body surface area, increased in the Pa-group and the AW-group, but were unchanged or slightly decreased in the XW-group in the midterm cardiac angiography. We believe that postoperative pulmonary stenosis can be best avoided if modified Pacifico method is used. The cases in which postoperative pulmonary stenosis or coronary artery compression is anticipated such as those with side-by-side aortopulmonary relationship or after pulmonary artery banding, should be operated upon using fresh autologous pericardial patch.

[Valve replacement in an infant with congenital mitral stenosis--report of a case which showed hemodynamics similar to that of hypoplastic left heart syndrome in neonatal period]

In the neonatal period, the patient showed severely hypoplastic left ventricle, severe mitral stenosis, patent foramen ovale and patent ductus arteriosus with right-to-left shunting, which resulted in the hemodynamics similar to that of hypoplastic left heart syndrome. However, progressive left ventricular growth was recognized after spontaneous closure of the foramen ovale, and the cardiac catheterization at the age of 6 months revealed almost normal left ventricular volume and systolic forward flow from the left ventricle to the descending aorta. The operation was performed at the age of 7 months under cardiopulmonary bypass with moderate hypothermia and cardiac arrest. The mitral leaflets were thickened and dysplastic, two short papillary muscles were hypertrophic and very closely related, and the chordae were extremely short and fused each other making the interchordal space obstructed. Because the mitral annular diameter (13 mm) was too small for conventional valve replacement, the prosthetic valve (CarboMedics #16) was sewn to the left atrial wall 5 to 10 mm above the mitral annulus. The ductus arteriosus was ligated. The postoperative cardiac catheterization showed residual pulmonary hypertension, but pulmonary vascular response to oxygen-inhalation was recognized. We consider that there were two important hemodynamic factors which led to successful biventricular repair in this case. First, early spontaneous closure of the foramen ovale accerelated the left ventricular growth and prevented right ventricular failure resulting from increased pulmonary blood flow. Second, considerable part of the systemic output was supplied through a large ductus arteriosus, and thus over-systemic pulmonary hypertension was avoided.

[Reoperation for transposition of the great arteries: mid-term results and reoperation after arterial switch operation]

The arterial switch operation for transposition of the great arteries is now widely accepted as the therapeutic method of choice. As of December 1993, a total of 162 patients underwent the arterial switch. There were 100 patients with transposition and intact ventricular septum, 48 with a ventricular septal defect, 14 with ventricular septal defect and arch anomalies (coarctation: 11, interruption: 3). Early and late mortality were 3.7% (6 patients) and 4.5% (7 patients), respectively. Postoperative pulmonary stenosis (> 30 mmHg) was noted in 33 patients (22%), aortic regurgitation (> mild) in 20 (13%), supravalvular aortic stenosis (> 20 mmHg) in 5 (3%) and mitral regurgitation (> mild) in 5 (3%). Reoperation was performed in 27 patients with no mortality. Mean interval between the switch and the reoperation was 30 months. Twenty-three patients with pulmonary stenosis underwent patch plasty of pulmonary artery. Two children with severe aortic regurgitation underwent aortic valve replacement. Two patients who had undergone one-staged repair for interruption complex were reoperated due to supravalvular aortic stenosis and pulmonary stenosis. Actuarial survival and freedom from reoperation at 9 years were 90% and 69%, respectively.

[Rigidity abolished by intravenous dantrolene in a patient with Parkinson's disease under spinal anesthesia]

Spinal anesthesia was given to a patient with right femur fracture and Parkinson's disease (PD). Although sufficient analgesia was obtained up to L1 level after spinal anesthesia, the muscular rigidity remained. Furthermore, tremor of the upper extremities continued. After administering dantrolene sodium (DT) intravenously, these untoward features were abolished. These findings suggest that DT abolishes rigidity and tremor in PD, and is useful for the management of anesthesia for a patient with PD.