Carbon dioxide prevents pulmonary overcirculation in hypoplastic left heart syndrome.

Circulatory and metabolic homeostasis in patients with hypoplastic left heart syndrome is dependent on a delicate balance between systemic and pulmonary blood flow. Hypocarbia can result in a marked decrease in pulmonary vascular resistance accompanied by pulmonary overcirculation, systemic hypotension, metabolic acidosis, and death. This report illustrates that early and precise control of the arterial carbon dioxide tension using inspired carbon dioxide can be effective in preventing or treating instability arising during management of a patient with hypoplastic left heart syndrome.     

Follow-up study of pulmonary artery configuration in hypoplastic left heart syndrome

Objective. Pulmonary artery (PA) distortion significantly compromises the outcome of the staged approach to the Fontan operation in patients with hypoplastic left heart syndrome (HLHS). This retrospective study was designed to investigate the influence of the initial operation on postoperative PA anatomy. Methods. Forty-nine patients with HLHS and its variant were enrolled in this study. As an initial palliation, the Norwood operation with a modified Blalock-Taussig (BT) shunt was performed in 12, the Norwood operation with a right ventricle to pulmonary artery (RV-PA) shunt in 31, and bilateral PA banding in 6. The incidence and risk factors of postoperative central pulmonary artery stenosis (PS) were investigated, and the PA configuration was followed up until post-Fontan status. Results. Twenty-two patients (51.2%) had developed central PS after the Norwood operation (33.3% with a BT shunt vs. 58.1% with a RV-PA shunt). The RV-PA shunt with a polytetrafluoroethylene (PTFE) patch at the distal pulmonary stump significantly decreased the central PS (P = 0.035). The PA index after the Norwood operation was not statistically different between the BT and RV-PA shunt groups, although in the RV-PA group it was significantly higher in patients with a PTFE patch on the distal PA stump. PA plasty was performed in 16 patients in the second-stage palliation and in 15 with the Fontan completion. Freedom from PA plasty was significantly lower in the RV-PA shunt group than in the BT shunt group (63.5% vs. 31.1% at 5 years, P = 0.034). Six patients initially palliated with bilateral PA banding had no stenosis at the banding site in the Norwood + Glenn operation, and one patient required stent placement for left PS in the Fontan completion. Post-Fontan catheterization (n = 31) showed central venous pressure of 11.5 ± 2.6 mmHg, cardiac index of 3.6 ± 0.8 l/kg/min, and PA index of 194.0 ± 58.4 mm²/m²; there was no difference between the groups. Conclusion. The incidence of central PS after the Norwood operation was significant, and the shunt type and procedure for the distal PA stump influenced the postoperative configuration of the central PA. With an aggressive surgical approach to central PS, PA anatomy was satisfactory with good hemodynamic variables after Fontan completion. Bilateral PA banding did not cause later vascular deformity. Presented at the 59th Annual Scientific Meeting of the Japanese Association for Thoracic Surgery, held in Tokyo, Japan, October 1–4, 2006     

Bilateral pulmonary artery banding for resuscitation in hypoplastic left heart syndrome

We report a case of a hypoplastic left heart syndrome with a nearly intact atrial septum and an obstructed anomalous pulmonary to systemic venous connection. Surgical atrial septectomy followed by bilateral pulmonary artery banding provided an optimal condition for the Norwood operation.     

Fontan procedure for hypoplastic left heart syndrome.

Since 1985, 354 neonates have undergone palliative reconstruction for hypoplastic left heart syndrome with 109 early deaths and 12 late deaths. Of the survivors, before 1989, 77 patients underwent a subsequent modified Fontan operation, consisting of baffling the atrial septal defect to the tricuspid valve (initial 25 patients) or intraatrial baffling of the inferior vena cava to the pulmonary arteries and superior vena cava (52 patients). There were 17 early deaths and three late deaths. Major serous effusions developed in 42 patients (54%) after Fontan operation. Since 1989, a staged approach to Fontan's operation was undertaken in an effort to reduce the volume load of the right ventricle as early as possible, to minimize the impact of rapid changes in ventricular geometry and diastolic function that can accompany a primary Fontan operation, and to reduce effusive complications. Thus, at a mean age of 6 months, 121 patients have undergone closure of aortopulmonary shunt, augmentation of central pulmonary arteries, and association of the superior vena cava with the branch pulmonary arteries (hemi-Fontan procedure). Of these, 61 patients have already undergone completion of the Fontan procedure with six early deaths and three late deaths. Major serous effusions developed in 28 patients (46%) with the staged Fontan. For perspective, the contemporary experience since January 1991 consists of 58 neonates who have undergone initial palliation with 11 deaths (19%), 17 patients who have undergone the hemi-Fontan procedure with one death (6%), and 21 patients who have undergone completion of the Fontan operation with one death (5%).(ABSTRACT TRUNCATED AT 250 WORDS)     

Surgical treatment for hypoplastic left heart syndrome.

Once considered a uniformly fatal condition, the outlook for newborns with hypoplastic left heart syndrome has been dramatically improved with either a protocol of staged reconstruction or cardiac transplantation. Currently, a significant shortage of suitable donor hearts restricts the applicability of transplantation for most newborns. At the University of Michigan, we have adopted a policy of staged reconstruction for all patients with hypoplastic left heart syndrome, reserving transplantation only for those unsuitable for reconstructive techniques. Between January 1990 and September 1998, 303 patients underwent the Norwood operation for classic hypoplastic left heart syndrome with an overall hospital survival of 76%. Among patients considered at standard risk, survival was significantly higher (86%) than that for those patients with important risk factors (42%), p = 0.0001. Adverse survival was most strongly associated with significant associated noncardiac congenital conditions (p = 0.008) and severe preoperative obstruction to pulmonary venous return (p = 0.03). Survival following second stage reconstruction with a hemi-Fontan or bidirectional Glenn procedure was 98%. The Fontan procedure has been completed in 117 of these patients with a hospital survival rate of 91%. Survival after the Fontan procedure improved significantly when the second stage of the reconstruction was completed with a hemi-Fontan procedure compared to a bidirectional Glenn, 98% vs 81%, p < .05. Among the patients considered at standard risk, actuarial survival was 70% at 5 years. The largest decrease in survival occurred in the first month of life and late deaths affected primarily those patients in the high risk group. Neurodevelopmental outcome studies demonstrated normal verbal and performance scores in the majority of patients. Among centers utilizing a protocol of transplantation, donor organ shortages have resulted in a mortality of approximately 25% while awaiting transplantation with 5 year survival rates for those actually receiving organs essentially equal to those for staged reconstruction. Staged reconstruction and transplantation have significantly improved the intermediate-term outlook for patients with hypoplastic left heart syndrome. Factors addressing improvements in early first stage survival following the Norwood would be expected to add significantly to an overall improved late outcome. Outcome following cardiac transplantation is limited by donor availability in addition to the late complications of infection, rejection, graft atherosclerosis, and lymphoproliferative disease.     

Circumflex coronary artery from right pulmonary artery in hypoplastic left heart syndrome

We report the case of a newborn with the very rare association of hypoplastic left heart syndrome and aberrant origin of the circumflex coronary artery from the right pulmonary artery. This condition can jeopardize the result of the Norwood palliation.     

Surgical treatment of hypoplastic left heart syndrome

Hypoplastic left heart syndrome (HLHS) was previously uniformally fatal within the first month of life. The development of the Norwood stage I operation has afforded new hope to the families of newborn infants with this defect. Recent, modification of the Norwood procedure has improved the surgical results. The one-year survival rate after the Norwood procedure is from 50% to 70% in major institutions. The results of second palliation (hemi-Fontan operation or bidirectional Glenn operation) are nearly acceptable. Recently, fetal echocardiography has allowed early diagnosis of HLHS, and after a prenatal diagnosis of HLHS, couples may be offered termination of the pregnancy. It is necessary to improve the results of the Norwood stage I operation, to save more fetuses and neonates with HLHS.     

Mechanical limitation of pulmonary blood flow facilitates heart transplantation in older infants with hypoplastic left heart syndrome.

OBJECTIVES: Progression of pulmonary vascular disease limits heart transplantation for hypoplastic left heart syndrome (HLHS) to early infancy. Our objective was to assess the impact of bilateral pulmonary artery banding (PAB) on the operative courses of HLHS infants transplanted at ages older than 4 months. METHODS: Courses of all HLHS patients in our center who remained listed to age >or=120 days before heart transplantation were assessed. Patients undergoing transplantation after standard management (control group) were compared to patients having a prior pulmonary blood flow limiting procedure (PAB group). RESULTS: Of 16 identified patients, one crossed over to stage I Norwood on day 185 and died post-operatively. Fifteen patients were transplanted at age >or=120 days (control group n=9, PAB group n=6). Four PAB patients had open PA band placement. Two PAB patients underwent experimental percutaneous bilateral internal pulmonary artery flow limiting device insertion. The PAB group mean age at banding was 141+/-54 days, and mean interval from PAB to transplant was 35+/-31 days (range 1.5-68 days). No differences in age at transplant, weight at transplant, warm graft ischemia time or total graft ischemia time were detected between groups. Mean times of mechanical ventilation (control 143+/-69h vs. PAB 44+/-13h), inhaled nitric oxide (control 126+/-70h vs. PAB 37+/-9h), inotropic support (control 171+/-64h vs. PAB 87+/-17h), intensive care unit (ICU) stay (control 8.3+/-2.7 days vs. PAB 4.5+/-1.4 days), and hospital stay (control 10.4+/-3.9 days vs. PAB 7.0+/-1.1 days) were all lower in the PAB group (P<0.05 all comparisons). Two control patients died, three required extracorporeal membrane oxygenation (ECMO), and six did not tolerate primary chest closure. No PAB patient died or required ECMO. All PAB patients tolerated primary chest closure. All PAB patients had widely patent branch pulmonary arteries with no re-interventions to date. All hospital survivors remain alive (mean follow-up, control 50.2 months, PAB 11.5 months). CONCLUSIONS: Pre-transplant mechanical limitation of pulmonary blood flow simplified management and reduced morbidity for HLHS patients undergoing heart transplantation at ages >or=4 months. This strategy extends the permissible transplant waiting time in older infants with HLHS.     

Norwood procedure for hypoplastic left heart syndrome associated with valvular pulmonary stenosis

Association between hypoplastic left heart syndrome and valvular pulmonary stenosis is very rare. Severity of valvular pulmonary stenosis in this setting limits management options. Consequently, patients with this condition are considered poor candidates for Norwood stage one reconstruction. Herein, we describe a newborn with hypoplastic left heart syndrome and significantly dysplastic pulmonary valve who successfully underwent the Norwood procedure with neoaortic valve reconstruction. Therefore, the Norwood procedure with neoaortic valve reconstruction might be an option for this difficult condition.     

Surgical treatment for hypoplastic left heart syndrome

Once considered a uniformly fatal condition, the outlook for newborns with hypoplastic left heart syndrome has been dramatically improved with either a protocol of staged reconstruction or cardiac transplantation. Currently, a significant shortage of suitable donor hearts restricts the applicability of transplantation for most newborns. At the University of Michigan, we have adopted a policy of staged reconstruction for all patients with hypoplastic left heart syndrome, reserving transplantation only for those unsuitable for reconstructive techniques. Between January 1990 and September 1998, 303 patients underwent the Norwood operation for classic hypoplastic left heart syndrome with an overall hospital survival of 76%. Among patients considered at standard risk, survival was significantly higher (86%) than that for those patients with important risk factors (42%), p=0.0001. Adverse survival was most strongly associated with significant associated noncardiac congenital conditions (p=0.008) and severe preoperative obstruction to pulmonary venous return (p=0.03). Survival following second stage reconstruction with a hemi-Fontan or bidirectional Glenn procedure was 98%. The Fontan procedure has been completed in 117 of these patients with a hospital survival rate of 91%. Survival after the Fontan procedure improved significantly when the second stage of the reconstruction was completed with a hemi-Fontan procedure compared to a bidirectional Glenn, 98% vs 81%, p<.05. Among the patients considered at standard risk, actuarial survival was 70% at 5 years. The largest decrease in survival occurred in the first month of life and late deaths affected primarily those patients in the high risk group. Neurodevelopmental outcome studies demonstrated normal verbal and performance scores in the majority of patients. Among centers utilizing a protocol of transplantation, donor organ shortages have resulted in a mortality of approximately 25% while awaiting transplantation with 5 year survival rates for those actually receiving organs essentially equal to those for staged reconstruction. Staged reconstruction and transplantation have significantly improved the intermediate-term outlook for patients with hypoplastic left heart syndrome. Factors addressing improvements in early first stage survival following the Norwood would be expected to add significantly to an overall improved late outcome. Outcome following cardiac transplantation is limited by donor availability in addition to the late complications of infection, rejection, graft atherosclerosis, and lymphoproliferative disease.     

Bilateral pulmonary artery banding for hypoplastic left heart syndrome and related anomalies

Objective Bilateral pulmonary artery banding is considered an option for initial palliation in high-risk patients with hypoplastic left heart syndrome or related anomalies. However, there are potential interim morbidities, including ductal constriction, compromised growth of the ascending aorta, and pulmonary artery stenosis at the banding site. In addition, there are still controversies regarding the optimal timing and choice of the second-stage operation. Methods Between February 2003 and October 2005, twelve high-risk patients with hypoplastic left heart syndrome or related anomalies underwent bilateral pulmonary artery banding. An atrial septal defect was created simultaneously when the septum was intact or the defect was restrictive. After the procedure, intravenous prostaglandin E₁ was continuously administered. Results The median weight was 3.0 kg (range 1.8–3.6 kg), and the median age was 16 days (range 0–27 days). Atrial septum defect creation was performed simultaneously in two patients. Ten of the twelve patients were discharged from the hospital. One patient died of progressive multiple organ failure and another patient died of cerebral hemorrhage. Eight patients developed various degrees of ductal constriction and required dose adjustment of prostaglandin E₁. Two patients underwent ductal arteriosus stent placement: one was unsuccessful owing to the size mismatch between the stent and the ductus. The diameter of the ascending aorta remained unchanged until the time of the second-stage operation, except in two patients who had a sufficiently sized aorta at the time of pulmonary artery banding. Pulmonary arterial branch stenosis developed at the banding site in three patients. At the time of the second-stage operation, the Norwood procedure was performed in seven patients, biventricular repair in two, and Norwood plus Glenn procedure in one. Conclusion Bilateral pulmonary artery banding is an option to salvage high-risk neonates with hypoplastic left heart syndrome or related anomalies. However, it is associated with high interstage morbidity, and patients may benefi t from early conversion to the Norwood operation.     

Tricuspid valve repair in hypoplastic left heart syndrome

OBJECTIVES: Currently, the survival for the Norwood procedure for hypoplastic left heart syndrome is approximately 90% in selected centers. However, the development of tricuspid regurgitation remains a significant obstacle to successful staged repair in a subset of these patients. The results of tricuspid valve repair in this challenging patient population remain largely unknown. METHODS: Twenty-eight patients with significant (3-4+) tricuspid regurgitation after the Norwood procedure required tricuspid valve repair from August 1995 through December 2002. The clinical and Doppler-echocardiographic data were reviewed to determine the efficacy of repair and patient outcome. RESULTS: Follow-up was 96% complete (27/28). Patients were divided into 2 groups on the basis of tricuspid regurgitation at late follow-up: those with a successful late outcome (0-2+) and those with a poor outcome (3-4+). There were 17 (63%) patients with a successful result and 10 (37%) with an adverse outcome. Age, weight, follow-up duration, valve anatomy, and stage of palliation were not significantly different between groups. Early postoperative 0 to 2+ regurgitation was associated with a durable result (P =.012) and preserved ventricular function (P =.04). Need for repair other than a partial annuloplasty was predictive of a poor outcome (P =.04). Overall survival was 67% (18/27). Survival was 94% (16/17) for patients with a successful late result versus 20% (2/10) for those with a poor outcome (P =.0002). CONCLUSIONS: Tricuspid valve repair can be accomplished in this challenging patient population with excellent results. Successful tricuspid valve repair is predictive of continued good valve function and preserved right ventricular function. Successful valve repair at late follow-up predicts excellent late survival.