Ilkka Mattila

Neurodevelopmental Burden at Age 5 Years in Patients With Univentricular Heart

BACKGROUND: Despite increasing survival, patients with hypoplastic left heart syndrome (HLHS) and other forms of functionally univentricular heart defects (UVHs) remain at increased risk of long-term neurodevelopmental deficits. METHODS: A nationwide sample of 23 patients with HLHS, 13 with UVH, and 40 controls were followed prospectively until the age of 5 years, when neurologic, neuropsychological, and motor examinations and brain MRI were performed. RESULTS: The median full-scale IQ was significantly lower in patients with HLHS (97, P < .001) and patients with UVH (112, P = .024) compared with controls (121). Major neurodevelopmental impairment was found in 26% of the patients with HLHS and 23% of those with UVH, and minor neurologic dysfunction was found in 43% and 46%, respectively. MRI revealed abnormalities, mostly ischemic changes of different degrees, in 82% of the patients with HLHS and in 56% of those with UVH. Prominent changes were significantly associated with neurodevelopmental findings and parental reports of adaptive behavior. In linear regression, significant risk factors for a worse outcome were a history of clinical seizures in connection with the primary operation, a lower diameter of the neonatal ascending aorta, and several pre-, peri-, and postoperative factors related to the primary and bidirectional Glenn operations. CONCLUSIONS: Although median cognitive performance was within the normal range, neurodevelopmental and brain MRI abnormalities were found in the majority of the patients with UVH, and especially in those with HLHS, at preschool age. Both a narrowed ascending aorta and operation-related factors contributed to these findings.

Neurodevelopment in children with hypoplastic left heart syndrome.

OBJECTIVE To assess neurodevelopment in children with hypoplastic left heart syndrome (HLHS) or other types of functionally single ventricle (univentricular heart, UVH) and to estimate the effect of possible clinical predictors on outcome. STUDY DESIGN A total of 22 patients with HLHS and 14 with UVH, surviving after palliative surgery performed in the same center, and 42 healthy control subjects were examined at a median age of 30.2 months neurologically and according to the Bayley Scales of Infant Development in a population based prospective neurodevelopmental follow-up study. RESULTS The mean Mental Developmental Index was significantly lower (89.9) in patients with HLHS than in control subjects (105.5, P<.001), whereas there was no difference between patients with UVH (98.5) and control subjects. The mean Psychomotor Developmental Index in patients with HLHS (80.7, P<.001) as well as in those with UVH (94.5, P=.016) was significantly inferior to that in control subjects (105.3). CONCLUSIONS In patients with HLHS, mean Mental Developmental Index lags behind control subjects. Psychomotor Developmental Index is impaired in patients with both HLHS and UVH. Routine neurodevelopmental follow-up is recommended for this seriously ill patient group.

Prospective follow-up study of children with univentricular heart: Neurodevelopmental outcome at age 12 months

OBJECTIVES Despite recent advances in the treatment of children with univentricular heart, their neurodevelopmental outcome remains a major concern. METHODS This prospective follow-up study evaluated the neurodevelopmental outcome of 23 patients with hypoplastic left heart syndrome, 14 with other forms of univentricular heart, and 46 healthy control subjects at a median age of 12.2 months. The Griffiths Developmental Scale and Alberta Infant Motor Scale served for developmental evaluation. RESULTS The mean Griffiths developmental quotient of children with hypoplastic left heart syndrome was significantly less (91.6) than that of control children (106.8, P < .001). Patients with univentricular heart scored significantly lower than control subjects only in the gross motor domain (P = .001) but not in overall development (100.6). Alberta Infant Motor Scale scores were significantly lower in children with hypoplastic left heart syndrome (37.5, P < .001) and univentricular heart (43.5, P = .011) than in control subjects (53.3). In linear regression a diagnosis of hypoplastic left heart syndrome (P = .016), a clinical history of seizure (P = .002), and the highest plasma lactate level after the bidirectional Glenn operation (P = .045) were significantly associated with the developmental quotient. CONCLUSIONS At age 1 year, the level of development of children with univentricular heart was significantly lower than for control subjects only in motor skills, whereas children with hypoplastic left heart syndrome had a more widespread developmental delay. The diagnosis, a clinical seizure history, and increased plasma lactate levels after the bidirectional Glenn operation emerged as risk factors.

Mediastinal neurogenic tumours: early and late results of surgical treatment

Early and late results of surgery for neurogenic mediastinal tumour were evaluated in 66 cases with a mean follow-up of 12 years. The series comprised 48 neurilemmomas, 8 neurofibromas, 7 ganglioneuromas, and neurinoma, neurofibrosarcoma and ganglioneuroblastoma each in one case. There were two early deaths (3%), one due to peroperative bleeding from the left subclavian artery and the other to acute myocardial infarction. Operative complications arose in 12 cases (18%), the most common being wound infection (3 cases). There were 17 late deaths (26.6%). In the neurilemmoma group, 3 of the 13 late deaths were related to the tumour or its treatment, and both deaths in the neurofibroma group were related to malignant transformation. Recurrence of tumour appeared in 3 of the 48 patients with neurilemmoma and also in the single patient with neurinoma as tumour classification. One neurilemmoma was a dumb-bell tumour, and operation in this case resulted in paraplegia. Malignant transformation appeared in 2 of the 8 neurofibromas 5 and 13 years postoperatively. Because of the risks of malignant degeneration and of recurrence, patients operated on for neurogenic mediastinal tumour should be carefully followed up for many years.

Direct reconstruction of the pulmonary artery during the arterial switch operation : An interesting surgical option with excellent hemodynamic results

BACKGROUND In transposition of the great arteries, reconstruction of the neo-pulmonary artery is a challenging surgical detail during the arterial switch procedure. We present early and midterm clinical and hemodynamic results of a direct reconstruction of the pulmonary artery avoiding prosthetic and autologous material. METHODS Between 1990 and June 1996, a total of 189 patients underwent the arterial switch procedure because of D-transposition of the great vessels. Of them, 47 underwent direct pulmonary artery reconstruction. Mean age at operation was 5.2+/-4.1 days and mean weight was 3.75+/-0.85 kg. Simple transposition of the great arteries was present in 13, transposition of the great arteries plus ventricular septal defect in 27, and more complex forms of transposition of the great arteries in 7 patients. The great vessels were side-by-side in 4 patients and in the anteroposterior position in 43 patients. The technique of direct pulmonary reconstruction includes extensive mobilization of both pulmonary artery branches into the hilum, posterior incision of the mean pulmonary artery into the bifurcation, and resuspension of the posterior commissure of the neo-pulmonary valve. A large anastomosis without any tension is then performed, using the anterior remnant aortic sinus of Valsalva to fit out the expected size of the neo-pulmonary artery. RESULTS Early mortality was 8.5% (4/47) in this particular group of patients. Postoperative echocardiography was performed before hospital discharge, 3 to 6 months postoperatively, and after a mean follow-up of 24 months. Of the 43 survivors, 37 patients had a pressure gradient across the pulmonary valve of less than 15 mm Hg. Mild pulmonary stenosis (pressure gradient of 15 to 30 mm Hg) was present in 4 and more severe supravalvar stenosis (pressure gradient > 30 mm Hg) in 2 patients. After a mean follow-up of 36 months, there was one redo operation to enlarge the right ventricular outflow tract. CONCLUSIONS Direct reconstruction of the neo-pulmonary artery-avoiding autologous pericardium and prosthetic material-may represent an interesting option during the arterial switch operation when the great vessels lie in the anteroposterior position. This technique is simple, and the hemodynamic midterm results are very favorable. The incidence of postoperative supravalvar pulmonary stenosis is low, and there may be considerable potential for unlimited tissue growth.

REAPPEARANCE OF HERING-BREUER REFLEX AFTER BILATERAL AUTOTRANSPLANTATION OF THE LUNGS

In combined heart-lung transplantation the afferent nerve pathways inevitably are transsected. In previous studies with en bloc heart-lung transplantation in dogs, we found altered regulation of breathing-abolition of Hering-Breuer reflex and response to hypercapnia inhalation stimulus consisting of augmented tidal volume with no change in respiratory rate-shortly after the operation. The long-term effects of pulmonary denervation on breathing regulation were now studied in dogs after staged bilateral pulmonary autotransplantation. Mechanical and electrical activities of the respiratory muscles were recorded during spontaneous breathing and after deflation and inflation with varying volumes of air. Five months postoperatively the duration of the respiratory cycle increased 2.5 times on inflation with 600 ml of air and occlusion of the airways, compared with tenfold prolongation in intact control dogs, indicating a partial return of the Hering-Breuer reflex after the autotransplantation. The duration of the EMG bursts in respiratory muscles increased in intact dogs and in those with bilateral lung autotransplants. In impulse frequency the response to stretching was less evident after autotransplantation. The mechanism mediating reappearance of Hering-Breuer reflex warrants further study.

Neurocognitive development and behavioral outcome of 2-year-old children with univentricular heart.

Recent advances in the treatment of children with severe congenital heart defects, such as hypoplastic left heart syndrome (HLHS) and other forms of univentricular heart (UVH), have significantly improved their survival rates. However, these children are at risk for various neurodevelopmental deficits. The aim of the present study was to assess cognitive development, expressive language, and behavior in 30-month-old children with univentricular heart. The participants were 22 children with HLHS, 14 with UVH, and 41 healthy control subjects. The Bayley Scales of Infant Development II, MacArthur Communicative Development Inventories, and Child Behavior Checklist were used for assessments. The results revealed that children with HLHS exhibited a significantly lower mean mental development index, more delays in expressive language functions, and more behavioral problems than did the control children. Two children with HLHS (9%) had mental development indexes below 50, indicating significantly delayed performance. The children with UVH differed from the control children with respect to their lower mean mental development index. These findings suggest that at the age of 30 months, neurodevelopmental deficits are especially prevalent in children with HLHS. Thus, early developmental screening, intervention, and neuropsychological follow-up until school age is recommended particularly for the children with HLHS.

Cardiac Tamponade and Different Modes of Artifical Ventilation

Cardiac tamponade after open‐heart surgery often occurs in a situation when the patient is still mechanically ventilated and needs circulatory support with catecholamines. To evaluate the effects of different modes of artificial ventilation and dopamine on cardiac tamponade, an experimental study was carried out in seven mongrel dogs. In pentobarbital ‐ N2O anaesthesia, a cardiac tamponade of 20 mmHg was produced by injecting 120–200 ml of normothermic saline into the pericardium. Intermittent positive pressure ventilation (IPPV) and positive end‐expiratory pressure (PEEP) ventilation with frequencies of 12 and 20 were tested before and after producing the tamponade. Cardiac tamponade produced a significant fall in arterial pressure and cardiac output, a significant rise in central venous pressure and only a slight increase in pulmonary arterial pressure. PEEP with the slower ventilation frequency of 12 produced additional, significant falls in cardiac output and systemic arterial pressure, which were not noted with the ventilation frequency of 20 and PEEP. Dopamine infusion increased the cardiac output by increasing the heart rate during tamponade. It is concluded that PEEP ventilation with a slow frequency should not be used if cardiac tamponade is suspected after open‐heart surgery, and that dopamine has a favourable effect on haemodynamics even in the presence of a severe cardiac tamponade.

Long-term follow-up of Björk-Shiley mitral valve replacement

Retrospective analysis was made of 176 patients who received a Bjork-Shiley mitral valve replacement in the period 1973 through 1982. Actuarial cumulative curves showed the 10-year and 5-year survival rates to be 79±3.4%. The functional status at follow-up was better than preoperatively in 77.1% of the patients. The hospital mortality was 9.1% and the late mortality was 3.6/100 patient years. Early complications included disc entrapment against the ventricular wall in three cases, wedging of chorda between disc and valve rim in two and posterior perforation of the left ventricle in three patients. There was no structural valve damage. Calculated per 100 patient years, the incidence of thromboembolism was 2.5, endocarditis 1.4 and prosthetic leak 1.8. One thrombosed valve was successfully replaced by a new prosthesis 11 years after the initial implantation. Jamming of the disc by tissue overgrowth necessitated a new valve implantation in one case. The incidence of early valve-related complications was high...

Combined Heart and Lung Autotransplantation and Regulation of Breathing

The effects of en bloc autotransplantation of the heart and both lungs on the regulation of breathing were studied in four mongrel dogs. Tidal volume, respiratory rate, airflow, airway pressure and electromyograms from the intercostal muscles and diaphragm were recorded before and after the transplantation. The dogs breathed air or a mixture of 5% CO2 and air. Airway closure at functional residual capacity (FRC) level and after insufflation of 200 ml air was used as a mechanical stimulus. The following observations were made. 1) Stimulation by 5% CO2 after the transplantation increased the ventilatory minute volume by increasing the tidal volume while the respiratory rate remained unaltered. Before transplantation, both tidal volume and respiratory rate increased in response to CO2 stimulation. 2) After transplantation, stretching of the airways did not cause apnea (Hearing-Breuer reflex abolished) as it did preoperatively. 3) CO2 inhalation increased the efficiency of the respiratory muscles as expressed by the ratio of mechanical work (tidal volume or pressure impulse) to electrical activities of the respiratory muscles. This was most obvious in the dogs with transplant when the airways were closed at FRC level. Elimination of the afferent impulses due to en bloc transplantation of the heart and both lungs therefore modified the efferent impulses to the respiratory muscles. This effect was seen after both chemical and mechanical stimuli.