Palliative right ventricle outflow reconstruction in tetralogy of Fallot with pulmonary atresia and hypoplastic pulmonary artery

The management of small pulmonary artery in tetralogy of Fallot (TOF) with pulmonary atresia (PA) is complicated. Our strategy is palliative right ventricle outflow tract reconstruction (RVOTR). The aim of this study is to determine whether palliative RVOTR is useful as the first stage operation. Since 1994, 7 patients with TOF, pulmonary atresia and hypoplastic pulmonary arteries underwent palliative RVOTR. All patients survived operation without complication except for 1. He had pseudoaneurysm at right ventricular outflow patch requiring aneurysmectomy and re-RVOTR 1.5 months after the initial RVOTR. Nine months after RVOTR in the average, pulmonary artery index (PAI) increased from 139 +/- 87 to 306 +/- 156 (p < 0.05). No patient had pulmonary high flow or pulmonary hypertension. Two of them had pulmonary coractation due to ductal tissue in the pulmonary artery, necessitating additional modified Blalock-Taussig shunts at 8 and 10 months old. One patient with TOF, PA, major aorto-pulmonary collateral artery (MAPCA) had corrective surgery after 2 additional operations and interventional catheterization. Five patients of this series already have undergone corrective surgery, whereas 1 is waiting for it. RVOTR is a useful method for pulmonary artery growth in patients with TOF, PA and diminutive pulmonary artery.     

Correlation of NYHA classification, bicycle ergometry and right heart haemodynamics after total correction of tetralogy of Fallot in adults

Thirty-two patients who had undergone correction of Fallot's tetralogy in adult life were examined on average 6.3 years postoperatively, at mean age 25.8 years. Palliative shunt operation had been performed in childhood in 28 cases. The clinical condition was good in 25 patients (78%). 13 of whom had mean gradient between right ventricle and pulmonary artery 16.0 +/- 4.2 mmHg and systolic right ventricular pressure 39.0 +/- 10.0 mmHg, while 12 had right ventricular pressure 62.6 +/- 16.3 mmHg. In these groups the maximum exercise capacity was, respectively, 136.7 +/- 36.1 and 106.1 +/- 30.8 W/min. Three other patients were in satisfactory, and four in poor clinical condition, with right ventricular systolic pressure, respectively, 74.3 +/- 10.9 and 91.5 +/- 60.0 mmHg. The gradient from right ventricle to pulmonary artery averaged 58.5 +/- 10.4 mmHg in the latter group but, despite the obstructed pulmonary outflow tract, the exercise capacity (116.7 +/- 28.9 W/min) was similar to that in the groups with better clinical results. It is concluded that in most patients with palliative surgery in childhood, tetralogy of Fallot can be successfully corrected in adult life. The causes of right ventricular impairment do not significantly reduce the exercise capacity.     

Pulmonary artery configuration after palliative operations for hypoplastic left heart syndrome

Pulmonary artery architecture and symmetry after palliative operations for hypoplastic left heart syndrome may affect subsequent suitability for a modified Fontan operation. Two-dimensional echocardiography was used to measure pulmonary artery diameter and assess symmetry after two types of systemic-pulmonary artery shunts: modified right Blalock-Taussig shunt (14 patients) and central shunt (from underside of aortic arch gusset to pulmonary artery confluence) (14 patients). Age, weight, preoperative diameter of right and left pulmonary arteries (proximal, middle, and distal segments), and mean interval between preoperative and postoperative echocardiographic studies (20.2 +/- 4.4 days in the Blalock shunt group; 19.1 +/- 6.8 days in the central shunt group) were similar. Early postoperatively, patients with a Blalock shunt showed a significant decrease in the diameter of all pulmonary artery segments except the distal right pulmonary artery. The diameters tapered from distal right to distal left pulmonary artery in this group. Patients with the central shunt had a significant decrease in the diameter of all pulmonary artery segments. There were no significant differences when cross comparisons were made of the various pulmonary arterial segments in patients after a central shunt. Similar findings persisted in 19 patients from both groups who had a late postoperative echocardiogram (mean interval between studies = 271 days in the group of 10 patients with Blalock shunt and 167 days in the group of nine patients with a central shunt). In conclusion, the central shunt preserves pulmonary artery symmetry, which may be important in candidates for the Fontan operation in infancy.     

A case for anatomic correction in atrioventricular discordance? Effects of surgery on tricuspid valve function

OBJECTIVE: To assess tricuspid valve function in atrioventricular discordance after palliative procedures (pulmonary artery banding and Blalock-Taussig shunt) and corrective procedures (anatomic and physiologic repair). METHODS: Tricuspid valve dysfunction was assessed by transthoracic echocardiography and graded as no regurgitation (0), mild (1), moderate (2), and severe (3) before and after palliative and corrective procedures performed in 97 patients with atrioventricular discordance between 1988 and 1999. Thirty-two percent had an isolated ventricular septal defect, 43% had a ventricular septal defect and pulmonary stenosis, and 16% had pulmonary stenosis. Twenty-six patients underwent pulmonary artery banding and 28 had a Blalock-Taussig shunt. Seventy patients underwent physiologic and 19 underwent anatomic repair. Six patients underwent one-ventricle repair. RESULTS: After pulmonary artery banding, the tricuspid regurgitation score decreased from 1.7 +/- 0.8 to 0.9 +/- 0.6 (P <.001). In patients who underwent a Blalock-Taussig shunt, the tricuspid regurgitation score increased from 0.7 +/- 0.5 preoperatively to 1.4 +/- 0.6 postoperatively (P <.001). After physiologic repair, there was no significant change in the tricuspid regurgitation score; however, 7 patients required additional repair or replacement. The regurgitation score was significantly reduced from 1.5 +/- 0.8 to 0.4 +/- 0.5 (P <.001) after anatomic repair. The operative mortality in patients who underwent physiologic repair was 7% as compared with 0% in the anatomic repair group (P =.59). The median follow-up was 3.2 years. CONCLUSIONS: Right ventricular volume loading (shunt) worsens tricuspid regurgitation, whereas volume reduction (banding) or left-to-right septal shift (anatomic repair) has beneficial effects. We have not observed a significant change in the tricuspid regurgitation score after physiologic repair. Anatomic repair can be performed in selected patients with atrioventricular discordance and provides superior functional results.     

Bi-directional cavopulmonary shunt: is accessory pulsatile flow, good or bad?

OBJECTIVE: Evaluation of the effect and long-term outcome of accessory pulsatile blood flow versus classical bi-directional cavopulmonary connection (BCPC). METHODS: Retrospective review of the medical and surgical records. RESULTS: Two-hundred and five patients (119 boys, 86 girls) underwent BCPC from 1990 to 1996. Accessory pulsatile flow was present in 68%, flow being maintained through the pulmonary trunc in 46%, systemic-to-pulmonary artery shunt in 13% and mixed in 7%, or patent ductus arteriosus in 2%. Patients with accessory pulsatile flow had lower hospital mortality (3% versus 5%), while mean pulmonary artery pressure (14.1 versus 12.6 mmHg P = 0.050) and increase of oxygen saturation (12.4 versus 8.7, P = 0.034) were significantly higher. The period of artificial ventilation (1.9 day) and ICU stay (6 days) did not differ for both groups. Late mortality was higher following accessory pulsatile flow (6% versus 1%). At late follow-up patients with accessory pulsatile flow had significantly higher oxygen saturation (mean 85 +/- 4%, versus 79 +/- 4%; P < or = 0.005). If subsequent completion of Fontan is considered the optimal palliation and subsequent systemic to pulmonary artery shunt, arteriovenous fistula and transplantation is considered a failure, patients with accessory pulsatile flow had significantly more and earlier completion of the Fontan procedure (mean 1.7 +/- 2.4 years, versus 2.7 +/- 4.4 years; P = 0.008). Survival is not influenced by age at bi-directional cavopulmonary shunt surgery, left or right functional ventricular anatomy or previous palliative surgery. One patient with accessory pulsatile flow developed systemic-to-pulmonary collateral's eventually requiring lobectomy. CONCLUSION: Despite two different initial palliative techniques the outcome was not significantly different. Accessory pulsatile blood flow appeared not to be a contra-indication for a completion Fontan procedure. Moreover, the data suggest that after accessory pulsatile flow can safely be performed, at late follow-up oxygen saturation is higher, while, significantly more and earlier completion of Fontan occurred. Age at bi-directional cavopulmonary shunt, basic left or right ventricular anatomy or previous palliative surgery did not influence survival.     

Classic Blalock-Taussig shunt in neonates

BACKGROUND: The choice of palliative procedure for neonates with congenital cyanotic heart defects remains controversial. Several reports have questioned whether the classic Blalock-Taussig shunt is adequate in neonates, because it shows a high rate of mortality and early shunt failure. The purpose of this study is to evaluate the early and late results of classic Blalock-Taussig shunt in neonates. METHODS: From December 1981 to December 1996, 31 neonates underwent a classic Blalock-Taussig shunt. Mean age at operation was 15.9 days (range, 2 to 28 days), and mean body weight was 3214 g (range, 2229 to 4468 g). The major diagnoses were pulmonary atresia with intact ventricular septum (6 patients) and with ventricular septal defect (4), univentricular heart (6), tricuspid atresia (5), tetralogy of Fallot (4), transposition of the great arteries (3), and double outlet right ventricle (3). RESULTS: There were no early deaths. There was one early shunt failure. The patient underwent a replacement of Blalock-Taussig shunt by vascular graft on the 1st postoperative day. Two patients with non-confluent central pulmonary artery underwent a contralateral modified Blalock-Taussig shunt on the 22nd and 42nd postoperative day, respectively. There were two late deaths before the definitive repair was performed. Twelve patients required an additional shunt operation. The mean interval between the initial and the second shunt procedure was 27.7 months (range, 6 to 67 months). Ten patients underwent definitive operation and the mean interval to that procedure was 55.5 months (range, 14 to 121 months). Shunt patency was 94.7+/-5.1% at 3 years. The freedom from cardiac event (cardiac deaths or repeat shunting procedure) was 80.5+/-7.1% at 1 year and 54.9+/-9.4% at 3 years. CONCLUSIONS: The classic Blalock-Taussig shunt has a low operative mortality and has provided excellent long-term palliation in the neonate. We conclude that a classic Blalock-Taussig shunt should be considered a reasonable choice in neonates requiring a palliative procedure for congenital cyanotic heart defects.     

法乐四联症伴肺动脉闭锁的外科治疗(附14例报告)

报告外科治疗法乐四联症伴肺动脉闭锁１４例。肺动脉瓣水平膜状闭锁１３例，主肺动脉干闭锁１例。肺动脉发育好，肺血由一粗大的动脉导管供给者９例；肺动脉发育不良、无动脉导管，肺血由体肺侧支供给者１例；肺动脉发育不良，由细的动脉导管和体肺侧支共同供给者４例。姑息性手术５例，一期根治９例，二期根治２例；死亡３例。作者对法乐四联症伴肺动脉闭锁的手术适应证、姑息性手术方法的应用及体肺侧支的外科处理原则进行了探讨。     

Results of systemic-to-pulmonary artery anastomosis for tricuspid atresia with reduced pulmonary blood flow.

Fifty-six patients with tricuspid atresia and decreased pulmonary blood flow received a systemic-to-pulmonary artery anastomosis as a preliminary operation. Thirty-five had a Waterston shunt, 12 a Blalock-Taussig anastomosis, and nine various other procedures. The age at operation ranged from 2 days to 10 years (median 4.5 months). Pulmonary atresia was present in eight newborn infants. Four patients (7%), all less than 3 months old, died in hospital from persistent servere hypoxia despite the palliative procedure. By actuarial methods, 93% of the survivors were alive at and after one year (longest follow-up:9.8 years), while 83% had not required further palliation at and after four years from the first operation. None of the patients subsequently restudied had raised pulmonary pressure or resistances, and in most of them the pulmonary arterial tree was deemed adequate for the Fontan operation.     

Surgical treatments of nonconfluent pulmonary arteries with congenital cardiac defects]

Pulmonary artery angioplasty or reconstruction was performed in seven patients with nonconfluent pulmonary arteries and congenital cardiac defects. Age of these patients were ranged from 6 months to 41 years old. Five of them had pulmonary truncal atresia and complex cardiac anomalies. Two of these five patients demonstrated nonconfluent pulmonary arteries due to deformities at ductal insertion of pulmonary arteries. Three patients had had previous systemic to pulmonary artery shunt operations which caused pulmonary artery distortions. Other two patients had intrapulmonary arterial obstructions due to pulmonary artery thrombosis. Patch pulmonary artery plasty was carried out in three patients, dilatation of severe stenotic pulmonary artery was done in one patient simultaneously with pulmonary valvotomy. Central shunt operation was added in one patient with the pulmonary artery which was unable to be reconstructed. Last two patients underwent intrapulmonary artery reconstruction with the rolled pericardial graft. Hospital death occurred in one patient with unproperly increased pulmonary blood flow by central shunt. Average follow-up period of these six survivors after operation was 1.4 +/- 0.8 years. As definite repairs, two patients had Fontan operation, two patients had right ventricle to pulmonary artery reconstruction. And remaining two patients are still to be followed until sufficient growth of pulmonary artery suitable for Fontan operation.     

The long-term clinical outcome of patients with tricuspid atresia. II. Influence of surgical procedures.

One-hundred and eleven patients with tricuspid atresia were seen during 1972-1982 and thirteen of these were not operated upon. The remaining 98 patients have undergone at least one operation. Those with low pulmonary blood flow had 1-4 shunt procedures; in 15 patients with high pulmonary blood flow the pulmonary artery was banded. The mortality rate after the first shunt was 10% (8/82), 9% after the second shunt (3/32) and 12% after the third and fourth shunts. Three out of 15 (20%) patients died after pulmonary artery banding. Twenty three patients underwent a Fontan operation and five died (22%); eighteen survivors are clinically well (after 1-7 years). One patient required a pacemaker implantation and revision of his Fontan procedure. The survivors of the palliative operations and the unoperated patients were more restricted, the older ones having developed pulmonary vascular obstructive disease, chronic heart failure or arrhythmias.     

The Blalock-Taussig shunt. Low risk, effective palliation, and pulmonary artery growth

The Blalock-Taussig shunt has been used at our institution in 64 infants with cyanotic congenital heart disease who required palliation. Thirty-one of these children were less than 2 months of age at the time of operation. There were no early shunt closures. There were two hospital deaths (3%). There was only one hospital death in the 31 patients less than 60 days old. According to a life-table analysis, 87% +/- 9% (+/- 95% confidence limits) of the shunts were functioning at 1 year and 78% +/- 12% at 2 years. Results are similar in the subgroup of children less than 60 days of age at the time of operation or in the subgroup of children weighing less than 3,999 gm at operation. In infants with small pulmonary arteries, pulmonary arterial growth was excellent (ipsilateral pulmonary artery/descending aorta ratio 0.70 leads to 0.95 in 550 days, p less than 0.001; contralateral ratio 0.73 leads to 0.99 in 550 days, p less than 0.001). The Blalock-Taussig shunt can be performed with low risk, provides excellent palliation, and is associated with excellent pulmonary artery growth.     

Outcome of patients with cyanotic congenital heart disease undergoing a second systemic-to-pulmonary artery shunt

BACKGROUND: Multiple systemic-to-pulmonary artery shunts often represent a deviation from the initial management strategy for cyanotic congenital heart disease. This study analysed the outcome in patients undergoing a second shunt. METHODS: Between 1965 and 1998, 80 patients required a second shunt. Patient age ranged from 11 days to 11.2 years at the initial shunt, and 4 months to 25.6 years at the second shunt. The interval between shunts ranged from 11 days to 19.6 years. RESULTS: The patient survival rates at 1, 6, 12, 60 and 120 months following the second shunt were 95.0 +/- 2.4%, 92.5+/-3.0%, 87.4+/-3.7%. 82.4+/-4.5% and 74.8+/-5.8%, respectively. Although excess pulmonary flow was not encountered after the second shunt, mode and incidence of morbidity were otherwise similar to the first one. Between 9 months and 7.5 years after the second shunt, 24 patients underwent successful definitive repair. Multivariable analysis identified pulmonary atresia (p=0.027) and a short (<1 year) interval between the two shunts (p=0.034) as the independent risk factors for long-term shunt failure. Single ventricle physiology (p=0.002) and a central approach for the second shunt (p=0.016) were independent risk factors for lack of application, or failure of intracardiac definitive repair. CONCLUSIONS: A significant limitation in longevity and quality of life is common in patients requiring a second shunt, especially those associated with pulmonary atresia, the single ventricle physiology heart, or ungraftably hypoplastic contralateral branch pulmonary artery to the first shunt. Since excess pulmonary blood flow leading to congenital heart failure and/or ventricular diastolic dysfunction is unlikely, all patients who preclude definitive repair due to decreased pulmonary blood flow even after the first shunt should be shunted again.     

Hemodynamic dysfunction in obesity hypoventilation syndrome and the effects of treatment with surgically induced weight loss.

Obesity hypoventilation syndrome (OHS), defined as a PaO2 less than or equal to 55 mmHg and/or PaCo2 greater than or equal to 47 mmHg, was found in approximately 8% of morbidly obese patients undergoing gastric surgery for morbid obesity and was frequently associated with clinically significant pulmonary hypertension and cardiac dysfunction. Forty-six morbidly obese patients, 26 with and 20 without OHS, underwent preoperative pulmonary artery catheterization. Although the two groups had similar values for percent ideal body weight, blood pressure, and cardiac index, the OHS patients had significantly higher mean pulmonary artery pressures (PAP), p less than 0.0001, and pulmonary artery occlusion pressures (PAOP), p less than 0.01. Eighteen OHS patients were restudied 3-9 months after gastric surgery. PaO2 increased from 50 +/- 10 to 69 +/- 14 mmHg, p less than 0.0001, and PaCO2 decreased from 52 +/- 7 to 42 +/- 4 mmHg, p less than 0.0001), after the loss of 42 +/- 19% excess weight. These changes were associated with significant decreases in PAP (from 36 +/- 14 to 23 +/- 7 mmHg, p less than 0.0001) and PAOP (from 17 +/- 7 to 12 +/- 6 mmHg, p less than 0.01). Significant correlations were noted between PAP and PAOP (r = +0.8, p less than 0.0001) and PAP and PaO2 (r = -0.6, p less than 0.0001). Both left ventricular dysfunction, defined as a PAOP greater than or equal to 18 mmHg, as well as pulmonary artery vasoconstriction, defined as PAEDP greater than 5 mmHg above PAOP, contributed to pulmonary hypertension in OHS patients. In conclusion, weight loss after gastric surgery for morbid obesity significantly improved arterial blood gases and hemodynamic function in OHS patients.     

Effect of parainfluenza infection on gas exchange and FRC response to anesthesia in sheep.

We examined the interaction of viral pneumonitis with the respiratory effects of halothane/N2O anesthesia in six tracheostomized sheep. Ventilation-perfusion (VA/Q) distribution, pulmonary artery pressure (PAP), metabolic rate (VO2), and functional residual capacity (FRC) measurements were compared in awake and anesthetized animals before and 1 week after inoculation by tracheal instillation of ovine parainfluenza type-3 (PI-3) virus. Awake shunt (VA/Q less than 0.005) was 0.6 +/- 0.4% (+/- standard deviation [SD]) before, versus 3.9 +/- 2.0% after PI-3 infection (P less than 0.05). Awake arterial O2 tension (PaO2) was 139.9 +/- 14.0 mmHg before and 114.5 +/- 8.7 mmHg after infection (P less than 0.05). Mean PAP increased from 6.0 +/- 1.9 mmHg before to 11.5 +/- 1.6 mmHg after infection (P less than 0.05). Anesthesia shunt increased to 5.7 +/- 2.3% before and 11.2 +/- 3.4% after PI-3 (P less than 0.05 for the change from awake, and P less than 0.05 for a PI-3 anesthesia shunt difference). PAP was not significantly different from awake, either before or after infection. Anesthesia also produced an average 14.8 +/- 3.8% FRC reduction before and 17.4 +/- 6.4% reduction after infection (P less than 0.05 for FRC reduction with anesthesia, not significantly different for PI-3). Three of the six sheep developed shunt at higher FRCs after infection, both awake and during anesthesia; however, the average slope of the shunt/FRC response to anesthesia was unchanged, suggesting that this was not a neurogenic form of auto-PEEP. We therefore conclude that viral infection significantly enhanced the pulmonary effects of anesthesia.     

Hypoxic pulmonary vasoconstriction disappears in a rabbit model of cavopulmonary shunt

BACKGROUND: Cavopulmonary shunt is widely known as an interim staging procedure in patients with single-ventricle physiology. However, the physiologic characteristics of the pulmonary arterial system after cavopulmonary shunt are not clearly understood. In this article, we developed a rabbit cavopulmonary shunt model and studied the morphologic changes and physiologic characteristics (namely, hypoxic pulmonary vasoconstriction) of pulmonary arteries after cavopulmonary shunt. METHODS: Male Japanese white rabbits aged 12 to 16 weeks were used for the study. In 5 rabbits, the superior vena cava was anastomosed to the right pulmonary artery in an end-to-side fashion, followed by a proximal side ligation of the right pulmonary artery (cavopulmonary shunt group). In 4 rabbits, the superior vena cava and the right pulmonary artery were dissected and clamped for 10 minutes without making a cavopulmonary shunt (sham group). Two weeks after the operation, we then measured the internal diameter of the acinar (internal diameter, 164 +/- 7 microm), the lobular (305 +/- 13 microm), and the segmental (669 +/- 16 microm) pulmonary arteries in both controlled and hypoxic conditions by using a specially designed x-ray television system. Also, morphometric measurements were made in the pulmonary arteries around the terminal bronchioles. RESULTS: Two weeks after the operation, the arterial oxygen tension under room air conditions was significantly lower in the cavopulmonary shunt group than in the sham group (68.2 +/- 2.2 mm Hg vs 91.1 +/- 1.9 mm Hg; P =.01). The baseline internal diameters in the acinar and the lobular (resistance), but not the segmental (conduit), pulmonary arteries on the anastomosed side of the cavopulmonary shunt group were significantly larger than those of pulmonary arteries on the nonanastomosed side of the cavopulmonary shunt group and the sham group. Moreover, the pulmonary arteries on the anastomosed side of the cavopulmonary shunt group did not respond to hypoxia, whereas those on the nonanastomosed side of the cavopulmonary shunt and sham groups did have local internal diameter reductions in the acinar and lobular arteries (-1.1% +/- 1.0% in the anastomosed side vs -17.7% +/- 3.5% in the nonanastomosed side vs -20.9% +/- 6.1% in the sham group; P =.03). In the morphometric studies, the internal diameter of the pulmonary artery accompanying the terminal bronchiole in the anastomosed side of the cavopulmonary shunt group was significantly larger, and the ratio of medial thickness relative to the outer diameter was smaller compared with ratios in the nonanastomosed side of the cavopulmonary shunt group and the sham group. CONCLUSIONS: We developed a rabbit cavopulmonary shunt model. In the anastomosed side of the cavopulmonary shunt group, the peripheral pulmonary arteries, which contributed greatly in regulating the pulmonary vascular resistance, had a local reduction in the basal vascular tone and no hypoxic vasoconstriction 2 weeks after the operation.     

Enhanced expression of nitric oxide synthase in the early stage after increased pulmonary blood flow in rats.

OBJECTIVE: Evidence that vasodilator nitric oxide mediates normal pulmonary vascular tone has led to the hypothesis that endothelial injury induced by congenital heart disease with increased pulmonary blood flow disrupts these regulatory mechanisms and its associated altered vascular reactivity. Therefore, we hypothesized that increased pulmonary blood flow results in altered expression of endothelial nitric oxide synthase (eNOS). METHODS: We created an arteriovenous shunt in female Wistar (5-week-old) and measured the change of pulmonary blood flow and pressure immediately after and 1 month after the shunt operation. The protein levels of eNOS in the lung tissues of rats were assessed. RESULTS: The shunt immediately resulted in a significant increase in pulmonary blood flow (16.5 +/- 11.8% , pulmonary artery pressure (2.3 +/- 0.7 mm Hg), and blood O(2) saturation (16.1 +/- 11.8%) in the pulmonary artery. After 4 weeks, there was a significant increase in pulmonary blood flow (30.7 +/- 1.6%), pulmonary artery pressures (4.3 +/- 1.1 mm Hg), and blood O(2) content (43.3 +/- 17.5%). Western blot analysis demonstrated that eNOS protein was increased in the shunt lung 72 h after surgery and recovered to the control level 1 week later. CONCLUSION: This simple shunt model can induce early upregulation of eNOS expression with increased pulmonary blood flow and pulmonary artery pressure in rats.     

Inhalation administration of nitric oxide during selective pulmonary ventilation decreases the intrapulmonary shunt]

OBJECTIVE: To assess the effects of inhaled nitric oxide (NO) on oxygenation and hemodynamics in patients undergoing lung resection surgery during one-lung ventilation (OPV). PATIENTS AND METHODS: Prospective study of 16 patients aged 62 +/- 10 years scheduled for chest surgery under combined general and epidural anesthesia. During ventilation of only one lung, NO was administered for 15 minutes. Arterial blood and mixed venous blood samples were taken for analysis of blood gases and the calculation of intrapulmonary shunt. Pulmonary and systemic hemodynamic variables were also recorded using a Swan-Ganz catheter at three times: baseline (ventilation of both lungs), OLV, and with OLV plus NO (OLV NO). RESULTS: The most relevant data consisted of a significant decrease in shunt after start of NO inhalation in comparison with the level during OLV (31.1 +/- 0.5% versus 36 +/- 0.6%; p < 0.05). Arterial oxygen pressure decreased significantly during OLV and increased after start of NO (118.9 +/- 53.6 versus 155.4 +/- 78.5 mmHg; p < 0.05). Mean pulmonary artery pressure, pulmonary and systemic vascular resistances, and cardiac index did not change with inhalation of NO. CONCLUSIONS: Inhalational administration of NO during OLV significantly improves arterial oxygenation and decreases intrapulmonary shunt during OLV, without causing hemodynamic or systemic effects.     

Assessment of Blalock-Taussig shunts in children with complex cardiac anomalies associated with reduced pulmonary blood flow and total anomalous pulmonary venous drainage]

Eleven patients with syndromes of asplenia and polysplenia associated with total anomalous pulmonary venous drainage (TAPVD) were underwent Blalock-Taussig (B-T) shunt operation for reduction of pulmonary blood flow. The age of patients at operation were 6 days to 5 years (average 19.5 +/- 18.7 month). There were seven patients in supracardiac type and four in cardiac type of TAPVD. All patients didn't present obstruction to pulmonary venous return (PVO) before B-T shunt operation. There were one early (9%) and two late deaths (20%) after surgery. Although the hospital death was related to perioperative errors. Two late deaths were not due to the PVO. One of infants had moderately pulmonary congestion and cardiac failure after shunt procedure. Two patients were measured pressure gradient (3 to 4 mmHg) between common pulmonary vein to atrium chamber before shunt procedure. Repeated catheterization revealed that 6 of them could be measured pressure gradient, 3 to 7 mmHg, and no patients had clinical sign of the PVO. Our results demonstrated that B-T shunt operation could be satisfactory for syndromes of asplenia and polysplenia associated with reduced pulmonary blood flow and TAPVD.     

As originally published in 1996. Usefulness of pulsatile bidirectional cavopulmonary shunt in high-risk Fontan patients. Updated in 2002

BACKGROUND: A bidirectional cavopulmonary shunt has been performed for the high-risk Fontan patient. It is well known that in the presence of the bidirectional cavopulmonary shunt alone to secure pulmonary blood flow, the central pulmonary artery size decreases over time. We have performed pulsatile bidirectional cavopulmonary shunt (PBCPS), keeping pulmonary blood flow from the ventricle through the stenotic pulmonary valve, or a Blalock-Taussig shunt in patients who do not meet the criteria for the Fontan operation. METHODS: Eleven patients who underwent PBCPS between 1989 and 1993 were reviewed. We compared the results of cardiac catheterization immediately before PBCPS and during the postoperative observation period (310 +/- 257 days). RESULTS: Pulmonary blood flow and arterial oxygen saturation increased significantly after PBCPS (p = 0.01). Pumonary artery area index showed a tendency to increase (p = 0.11). The mean number of risk factors for the Fontan procedure decreased significantly from 1.8 +/- 1.1 to 0.7 +/- 0.8 after PBCPS (p < 0.05). Overall, 5 of the 11 patients (45.5%) met the criteria for the Fontan procedure, and a fenestrated Fontan procedure was carried out in 4 of them. CONCLUSIONS: The PBCPS is useful for high-risk Fontan patients not only in the staged Fontan operation, but also as definitive palliation.     

Right pulmonary artery development after modified Blalock-Taussig shunt (MBTS) in infants with pulmonary atresia, VSD and confluent pulmonary arteries

The ideal palliation for infants with pulmonary atresia, ventricular septal defect and confluent pulmonary arteries should promote normal development of the pulmonary artery branches. In 26 patients who survived a modified Blalock-Taussig shunt (MBTS) in the first year of life, the right pulmonary artery was measured before and after operation by two dimensional (2D) echocardiography. In each patient its size was compared to the normal value for the same body surface area. The patients were divided according to this ratio and according to the real size (mm). Although increased in all cases but two, the size of the right pulmonary artery remained remarkably less than normal in patients with an initially small right pulmonary artery. In view of these results, early palliative enlargement of the right ventricular outflow tract is probably advisable in infants with diminutive pulmonary arteries who do not show adequate pulmonary branch development after MBTS.