The hemodynamic findings related to the histologic changes in the small pulmonary arteries in congenital heart disease were analyzed with a left-to-right shunt. A lung biopsy was performed during the repair because of pulmonary arterial (PA) hypertension (mean PA pressure > or = 15 mmHg) in 38 patients. There were 13 patients whose age ranged from 2 years to 25 years old. A preoperative cardiac catheterization was performed to locate the site of the defect and to determine the preoperative hemodynamic findings. Among them, 29 patients had pulmonary vascular resistance (PVR) > 2.5 unit/m2. The lung biopsy specimens were investigated microscopically for the Heath- Edward grade, morphometric analysis of medial wall thickness (MWT) and the rate of the decrease in the pulmonary arteriolar concentration (PAC) obtained by the alvoelo-arterial ratio divided by patients' age. All patients were in the Heath-Edward grade I to III (29 patients in grade I). This grade correlated with the MWT, but did not correlate with a decrease in the PAC. The MWT and the rate of the decrease in the PAC did not accompany each other, but either one had the tendency dominate the pattern in individual patients. The MWT had a close correlation with the mean PA pressure and PVR, and an even closer correlation in patients with a high PVR and those older than 2 years of age. The rate of the decreased in the PAC showed a weak correlation with the shunt volume in patients over 2 years of age or with a large shunt. In the high flow group (PVR < 2.5 unit/m2, Qp/Qs > 2.0, n=14) the MWT was significantly thinner and the rate of the decrease in the PAC was significantly higher than the high resistance group (PVR > 2.5 unit/m2, Qp/Qs2 < 2.0, n=13). The rate of the decrease in the PAC correlated with the patients' age, but the MWT did not. The lung biopsy results in patients who had both left-to-right shunts and pulmonary hypertension showed that the rate of the decrease in the PAC was weakly related to the shunt volume and the MWT was related to the PA pressure and PVR. Either an increased MWT or the rate of the decrease in the PAC tended to dominate. These phenomena were prominent in patients older than 2 in whom a wide range of individual variations were noted in the morphometric pattern. The medial hypertrophy and the rate of the decrease in the PAC may be induced by different stimuli or that medial hypertrophy may play a role in preventing PAC decrease.
Adolescent ; Adult ; Child ; Child, Preschool ; Female ; Heart Defects, Congenital/*pathology/physiopathology/surgery ; Hemodynamics ; Human ; Infant ; Male ; Pulmonary Artery/*pathology/physiopathology

We performed this study to assess the correlation of residual pulmonary hypertension in the immediate postoperative period with that in the late follow-up period, to assess the histologic changes of pulmonary arteries (PA) at the time of repair for patients with congenital heart disease consisting of left-to-right shunt, and to clarify the role of lung biopsy in determining the operability and reversibility of pulmonary vascular changes. Lung biopsy was performed during repair in 38 patients, with a wide range of age, who had congenital left to right shunt and pulmonary hypertension. All were Heath-Edward grade III or less. Morphometric study included measurement of medial wall thickness (MWT) and decrease rate of pulmonary arterial concentration (PAC). Mean PA pressure in the immediate postoperative period was measured in all 38 patients. Follow-up cardiac catheterization was performed in 15 patients (average 3.8 years after repair). At operation, 5 patients of this late follow-up group were under 2 years of age and the other 10 were 2 or more. During catheterization, pulmonary hemodynamic reaction was observed both under room air inhalation and after inhalation of hypoxic gas FiO2 0.15. Mean PA pressure and pulmonary vascular resistance (PVR) in the immediate postoperative period had a significant correlation with PA pressure and PVR values before the operation, but not with morphometry, Heath-Edward grade, or with pulmonary hemodynamics in late follow-up. During the late follow-up study, 5 of the 15 patients had pulmonary hypertension (defined as mean PA pressure > or = 15 mmHg) under room air inhalation, and PA hypertension was induced in 4 additional patients after hypoxic gas inhalation. There was no incidence of PA pressure or PVR values registering above the preoperative level. The degree of PA hypertension showed a correlation with the rate of PAC decrease and also with patients' age-at-operation. Multiple regression analysis showed that both the rate of PAC decrease and the age-at-operation contributed significantly to the degree of PA hypertension. Some of the patients over age 2 had a decreased rate of PAC above the regression line, which none of the patients under age 2 experienced. In patients with Heath-Edward grade III or less, residual pulmonary hypertension in the immediate postoperative period was not correlated with histology, but in late follow-up, it was with PAC and the age-at-operation. Therefore, a decrease of PAC is assumed to be a totally or partially irreversible pulmonary vascular change depending on the patient's age-at-operation, while medial hypertrophy is thought to be a reversible pulmonary vascular change. Lung biopsy could play an important role in determining the reversibility of pulmonary vascular obstruction, particularly in patients older than 2 years. Ed- re highlights above: such hyphenation is optional, but if used then it should be applied consistently throughout the paper. As 3 of the 4 entries in the abstract use it, I have maintained it consistently below.
Adolescent ; Adult ; Biopsy ; Child ; Child, Preschool ; Follow-Up Studies ; Heart Defects, Congenital/*pathology/physiopathology/surgery ; Hemodynamics ; Human ; Pulmonary Artery/*pathology/physiopathology

BACKGROUNDThe present study was aimed to compare the effects of bilateral and unilateral bidirectional superior cavopulmonary shunt (b-BDG and u-BDG) on pulmonary artery growth and clinical outcomes.

METHODSThe 51 subjects enrolled in this study were divided into two groups: those receiving b-BDG (n = 21) and those receiving u-BDG (n = 30). Clinical records were reviewed retrospectively at a mean of 43.3 months after BDG procedures. Chi square and t-tests were performed to analyze the data.

RESULTSLeft and right pulmonary artery diameters increased 27% - 37% in both groups. The pulmonary artery index increased 37.2% after b-BDG and 27.0% after u-BDG. b-BDG patients experienced a significant decrease in mean hemoglobin concentration and hematocrit value, and a correlated change in postoperative diameter of left pulmonary artery (LPA) and pulmonary artery index (y = 0.2719, x = -1.8278; R = 0.564, P = 0.008). The change ratio of hemoglobin and postoperative LPA were also correlated in b-BDG patients (y = -0.0522x + 0.3539; R = -0.479, P = 0.028). Only one b-BDG patient versus twelve u-BDG patients needed total cavopulmonary connections 31.8 months after BDG surgery (P = 0.0074). Moreover, only one (4.8%) b-BDG patient but eight u-BDG patients (26.7%) developed pulmonary arteriovenous malformations.

CONCLUSIONSb-BDG increases bilateral pulmonary blood flow and promotes growth of bilateral pulmonary arteries, with preferable physiological outcomes to u-BDG. Results may imply that subsequent Fontan repair may not always be needed.

Cardiopulmonary Bypass ; methods ; Child ; Child, Preschool ; Female ; Fontan Procedure ; methods ; Heart Defects, Congenital ; physiopathology ; surgery ; Humans ; Infant ; Lung ; pathology ; surgery ; Male ; Pulmonary Circulation ; Retrospective Studies ; Treatment Outcome

The management of pulmonary atresia with intact ventricular septum (PA/IVS) remains controversial. The goal of separating systematic and pulmonary circulation can be achieved by biventricular or uni-ventricular (Fontan or one and a half ventricle repair) strategies. Although outcomes have been improved, these surgical procedures are still associated with high mortality and morbidity. An optimal strategy for definitive repair has yet to be defined. We searched databases for genetically randomized controlled trials (RCTs) comparing biventricular with uni-ventricular repair for patient with PA/IVS. Data extraction and quality assessment were performed following the guidelines of the Cochrane Collaboration. Primary outcome measures were overall survival, and secondary criteria included exercise function, arrhythmia-free survival and treatment-related mortality. A total number of 669 primary citations were screened for relevant studies. Detailed analysis revealed that no RCTs were found to adequately address the research question and no systematic meta-analysis would have been carried out. Nevertheless, several retrospective analyses and case series addressed the question of finding right balance between biventricular and uni-ventricular repair for patient with PA/IVS. In this review, we will discuss the currently available data.
Arrhythmias, Cardiac ; physiopathology ; prevention & control ; Cardiac Valve Annuloplasty ; methods ; mortality ; Fontan Procedure ; methods ; mortality ; Heart Defects, Congenital ; mortality ; pathology ; surgery ; Heart Ventricles ; abnormalities ; pathology ; surgery ; Humans ; Pulmonary Atresia ; mortality ; pathology ; surgery ; Retrospective Studies ; Survival Analysis ; Treatment Outcome