2-Tridecanone: A Naturally Occurring Insecticide from the Wild Tomato Lycopersicon hirsutum f.glabratum.

A nonalkaloid insecticide was isolated from the wild tomato Lycopersicon hirsutum f. glabratum and identified as 2-tridecanone, a compound 72 times more abundant in the wild tomato than in the cultivated tomato L. esculentum. Lepidopterous larvae (Manduca sexta and Heliothis zea) and aphids (Aphis gossypii) died when confined on 2-tridecanone-treated filter paper.

Influenza vaccination coverage among children aged 6-23 months - six immunization information system sentinel sites, United States, 2005-06 influenza season.

Beginning with the 2004-05 influenza season, the Advisory Committee on Immunization Practices (ACIP) recommended that all children aged 6-23 months receive influenza vaccinations annually. Other children recommended to receive influenza vaccinations include those aged 6 months-18 years who have certain high-risk medical conditions, those on chronic aspirin therapy, those who are household contacts of persons at high risk for influenza complications, and, since 2006, all children aged 24-59 months. Previously unvaccinated children aged <9 years need 2 doses administered at least 1 month apart to be considered fully vaccinated. This report assesses influenza vaccination coverage among children aged 6-23 months during the 2005-06 influenza season by using data from six immunization information system (IIS) sentinel sites. The findings demonstrate that vaccination coverage with 1 or more doses varied widely (range: 6.6% to 60.4%) among sites, with coverage increasing from the preceding influenza season in four of the six sites. However, <23% of children in five of the sites were fully vaccinated, underscoring the need for increased measures to improve the proportion of children who are fully vaccinated.

Aortic valve repair for adult congenital heart disease: A 22-year experience.

BACKGROUND: Aortic valve-preserving procedures have resulted in excellent outcomes in selected patients, particularly those with normal aortic valve leaflets and dilated aortic roots. However, several congenital heart lesions are associated with abnormal aortic valve leaflets. The long-term results of aortic valve repair for these lesions are not well defined. METHODS AND RESULTS: We reviewed the clinical records of 54 adult (age >18 years) patients who underwent repair of congenital abnormalities of the aortic valve between 1976 and September 1999. Follow-up data were available on 52 (96%) patients (mean 50+/-67 months, range 1 to 266). Patients underwent repair at a mean age of 34+/-14 years with associated diagnoses of subaortic stenosis (n=10), ventricular septal defect with prolapsing aortic valve (n=17), bicuspid aortic valve (n=23), sinus of Valsalva aneurysm (n=10), and bacterial endocarditis (n=2). There was 1 operative death (1.9%) and 3 late deaths. Survival at 5 and 10 years was 98+/-2% and 74+/-12%, respectively. Freedom from reoperation was 74+/-9% and 51+/-15% at 5 and 10 years, respectively. The presence of a ventricular septal defect predicted failure of valve repair (59% versus 22%, P:=0.01). A bicuspid aortic valve, subaortic stenosis, or the requirement for mitral valve surgery did not affect outcomes. CONCLUSIONS: Aortic valve repair in adult patients with congenital heart disease can be performed with minimal morbidity and mortality rates. The medium-term results of repair are acceptable, regardless of valvular or associated pathology. However, only 31 patients (57%) demonstrated long-term competence of the aortic valve, suggesting that most adult patients with congenital aortic valve disease will eventually require aortic valve replacement.

Are outcomes of surgical versus transcatheter balloon valvotomy equivalent in neonatal critical aortic stenosis?

BACKGROUND: For neonates with critical aortic valve stenosis who are selected for biventricular repair, valvotomy can be achieved surgically (SAV) or by transcatheter balloon dilation (BAV). METHODS AND RESULTS: Data regarding 110 neonates with critical aortic valve stenosis were evaluated in a study by the Congenital Heart Surgeons Society from 1994 to 1999. Reduced left ventricular function was present in 46% of neonates. The initial procedure was SAV in 28 patients and BAV in 82 patients. Mean percent reduction in systolic gradient was significantly greater with BAV (65+/-17%) than SAV (41+/-32%; P<0.001). Higher residual median gradients were present in the SAV versus BAV group (36 mm Hg [range, 10 to 85 mm Hg] versus 20 mm Hg [0 to 85 mm Hg], P<0.001). Important aortic regurgitation was more often present after BAV (18%) than SAV (3%; P=0.07). Time-related survival after valvotomy was 82% at 1 month and 72% at 5 years, with no significant difference for SAV versus BAV, even after adjustment for differences in patient and disease characteristics. Independent risk factors for mortality were mechanical ventilation before valvotomy, smaller aortic valve annulus (z score), smaller aortic diameter at the sinotubular junction (z score), and a smaller subaortic region. A second procedure was performed in 46 survivors. Estimates for freedom from reintervention were 91% at 1 month and 48% at 5 years after the initial valvotomy and did not differ significantly between groups. CONCLUSIONS: SAV and BAV for neonatal critical aortic stenosis have similar outcomes. There is a greater likelihood of important aortic regurgitation with BAV and of residual stenosis with SAV.

Impact of pulmonary valve replacement on arrhythmia propensity late after repair of tetralogy of Fallot.

BACKGROUND: Chronic pulmonary regurgitation after repair of tetralogy of Fallot (TOF) may lead to right ventricular dilatation, which may be accompanied by ventricular tachycardia and sudden death. We aimed to examine the effects of pulmonary valve replacement (PVR) on (1) certain electrocardiographic markers predictive of monomorphic ventricular arrhythmia and sudden death and (2) sustained atrial flutter/fibrillation and monomorphic ventricular tachycardia. METHODS AND RESULTS: We studied 70 patients who underwent PVR for pulmonary regurgitation and/or right ventricular outflow tract obstruction late after repair of TOF. Maximum QRS duration and QT dispersion were measured from standard ECGs before PVR and at the latest follow-up. Arrhythmia was defined as sustained atrial flutter/fibrillation or sustained monomorphic ventricular tachycardia. Concomitant intraoperative electrophysiological mapping and/or cryoablation were performed in 9 patients (60%) with preexisting ventricular tachycardia and 6 patients (50%) with preexisting atrial flutter. QRS duration remained unchanged in the study group (P=0.46), but it was significantly prolonged (P<0.001) in a comparable group of patients with repaired TOF who did not undergo PVR. At a mean follow-up of 4.7 years, the incidence of ventricular tachycardia diminished from 22% to 9% (P<0.001), and atrial flutter/fibrillation decreased from 17% to 12% (P=0.32). Intraoperative ablation prevented recurrence of preexisting tachyarrhythmia (0 of 15 patients). CONCLUSIONS: PVR in patients with previous TOF repair and chronic pulmonary regurgitation leads to stabilization of QRS duration and, in conjunction with intraoperative cryoablation, to a decrease in the incidence of preexisting atrial and ventricular tachyarrhythmia. When applicable, this combined approach should be used in patients late after repair of TOF.

What is the optimal age for repair of tetralogy of Fallot?

BACKGROUND: Controversy regarding the timing for the repair of tetralogy of Fallot centers around initial palliation versus primary repair for the symptomatic neonate/young infant and the optimal age for repair of the asymptomatic child. We changed our approach from one of initial palliation in the infant to one of primary repair around the age of 6 months, or earlier if clinically indicated. We examined the effects of this change in protocol and age on outcomes. METHODS AND RESULTS: The records of 227 consecutive children who had repair of isolated tetralogy of Fallot from January 1993 to June 1998 were reviewed. The median age of repair by year fell from 17 to 8 months (P:<0.01). The presence of a palliative shunt at the time of repair decreased from 38% to 0% (P:<0.01). Mortality (6 deaths, 2. 6%) improved with time (P:=0.02), with no mortality since the change in protocol (late 1995/early 1996). Multivariate analysis for physiological outcomes of time to lactate clearance, ventilation hours, and length of stay, but not death, demonstrated that an age <3 months was independently associated with prolongation of times (P:<0.03). Each of the deaths occurred with primary repair at an age >12 months. The best survival and physiological outcomes were achieved with primary repair in children aged 3 to 11 months. CONCLUSIONS: On the basis of mortality and physiological outcomes, the optimal age for elective repair of tetralogy of Fallot is 3 to 11 months of age.

Regional ventricular wall motion abnormalities in tricuspid atresia after the Fontan procedure.

OBJECTIVES: The purpose of this study was to determine whether wall motion abnormalities are present before or after the Fontan procedure in patients with a univentricular heart of the left ventricular type with an absent right atrioventricular valve connection (tricuspid atresia) and to assess the impact of such abnormalities on ventricular performance and clinical outcome. BACKGROUND: Normal systolic and diastolic ventricular function is critical for a successful Fontan repair. However, there have been no previous studies addressing the relation between regional ventricular function and hemodynamic factors. METHODS: Thirty-seven pediatric patients were studied with biplane ventricular cineangiography. There were 20 male and 17 female patients whose mean age at the time of the Fontan operation was 6.5 +/- 3.5 years (range 2.5 to 15.6). Eighteen patients were studied preoperatively, 25 at > 1 year postoperatively and 6 serially. Wall motion was assessed by a centerline method. Normal ranges for wall motion and other variables were established from 25 normal subjects. RESULTS: Wall motion abnormalities were observed in 2 of 18 patients preoperatively and in 11 of 25 patients postoperatively. Age at operation and ventricular volumes did not differ between postoperative patients who had normal (group I, 14 patients) or abnormal (group II, 11 patients) wall motion. However, ventricular mass and the mass/volume ratio were significantly greater and systolic variables and cardiac index were significantly lower in group II versus group I. Two patients in group I were considered to have a clinically poor outcome (persistent heart failure), and five in group II had heart failure, including one who died late. CONCLUSIONS: These observations suggest that postoperative regional wall motion abnormalities in this setting are not rare, may be related to excessive hypertrophy and may contribute to cardiac dysfunction and a poor clinical outcome.

Postoperative follow-up of fibromuscular subaortic stenosis.

OBJECTIVES: This study attempted to determine whether early subaortic resection at lower levels of obstruction reduces the rate of recurrence of subaortic stenosis or reduces secondary damage to the aortic valve, or both. BACKGROUND: Fibromuscular subaortic stenosis is a progressive condition, and at present it is unclear whether early operation reduces the recurrence rate along with decreasing the incidence of aortic insufficiency. METHODS: Thirty-seven patients with fibromuscular subaortic stenosis and no other significant cardiac abnormality who underwent open subaortic resection were evaluated. The preoperative, early and late postoperative catheterization or echocardiographic findings as well as the operative reports were reviewed. The median age at operation was 6.4 years (range 1.1 to 17.3). The entire group has been followed up postoperatively for a median of 5.2 years (range 1.1 to 11). Mean systolic gradients across the left ventricular outflow tract were used for the purpose of this study. RESULTS: There was a significant correlation between the preoperative mean systolic gradient and the incidence of preoperative aortic regurgitation and late postoperative aortic valve thickening as well as the incidence and degree of late postoperative aortic regurgitation. Late postoperative gradient and degree of aortic regurgitation correlated significantly with the follow-up interval. Aortic regurgitation was progressive in some patients despite subaortic resection. A preoperative mean gradient > 30 mm Hg provided a reasonable cutoff for the likelihood postoperatively of needing a reoperation, having a postoperative shelf, a thickened aortic valve, moderate aortic regurgitation or a gradient of > 10 mm Hg. CONCLUSIONS: Our results suggest that although early subaortic resection may not reduce the rate of recurrence of fixed subaortic stenosis, it is likely to reduce acquired damage to the aortic valve.

Systemic venous collateral development after the bidirectional cavopulmonary anastomosis. Prevalence and predictors.

OBJECTIVES: To determine the prevalence of systemic venous collaterals after the bidirectional cavopulmonary anastomosis and the factors associated with their development. BACKGROUND: Systemic venous collaterals have been found after cavopulmonary anastomosis. Methods. Cardiac catheterization was performed in 103 patients before and after a bidirectional cavopulmonary anastomosis. RESULTS: After surgery, 51 venous collaterals were identified in 32 patients (31%). Collateral development was associated with an abnormal superior vena caval connection (56% incidence vs. 26% with a single right superior vena cava, p = 0.01) and postoperative factors including pulmonary artery distortion (53% incidence vs. 22% without distortion, p = 0.002); increased superior vena caval mean pressure (14 +/- 5 mm Hg versus 11 +/- 4 mm Hg with no collaterals, p = 0.0002); increased pulmonary artery mean pressure (13 +/- 4 mm Hg vs. 11 +/- 4 mm Hg with no collaterals, p = 0.02); lower right atrial mean pressure (5 +/- 2 mm Hg vs. 6 +/- 3 mm Hg with no collaterals, p = 0.04); and increased mean gradient between superior vena cava and right atrium (8 +/- 3 mm Hg vs. 5 +/- 4 mm Hg with no collaterals, p = 0.0002). Using multiple logistic regression, only this last factor was independently associated with collateral development with an odds ratio per 1 mm Hg of 1.33 (95% CI 1.12-1.58, p = 0.001) for their presence. CONCLUSIONS: Systemic venous collaterals occur frequently after a bidirectional cavopulmonary anastomosis and are found postoperatively when a significant pressure gradient occurs between cava and right atrium.

Mitral regurgitation in hypertrophic obstructive cardiomyopathy: relationship to obstruction and relief with myectomy.

OBJECTIVES: This study examined: 1) the impact of myectomy on postoperative mitral regurgitation (MR) and 2) the association between the severity of MR and the left ventricular outflow tract (LVOT) gradient. BACKGROUND: For patients with hypertrophic obstructive cardiomyopathy (HOCM) and MR, controversy exists as to whether myectomy alone is sufficient in eliminating MR. Furthermore, the relationship between the degree of MR and the LVOT peak gradient has not been well defined. METHODS: We performed pre- and postoperative transthoracic as well as intraoperative transesophageal studies in 104 consecutive patients with HOCM undergoing septal myectomy. Left ventricular outflow tract gradient and the nature of MR were assessed. RESULTS: In the 93 patients without independent mitral valve disease, a relationship was observed between MR severity and the LVOT gradient. Left ventricular outflow tract gradient (mean +/- standard deviation) for trivial, mild, moderate and severe MR were: 23.2+/-19.1, 43.8+/-25.4, 70.1+/-21.0 and 104+/-21.0 mm Hg (p < 0.001). Early postoperative, MR was absent or trivial in 80%, mild in 19% and moderate in 1%. None of these patients required additional mitral valve surgery. For patients with independent mitral valve disease (n = 11), five required mitral valve surgery as well as myectomy. The remainder had significant reductions in the degree of MR with myectomy alone. CONCLUSIONS: For patients with HOCM and MR not due to independent mitral valve disease, myectomy significantly reduced the degree of MR, without requirement for additional mitral valve surgery. In these patients the severity of MR was directly related to the magnitude of the LVOT gradient.

Management and outcomes of right atrial isomerism: a 26-year experience.

OBJECTIVES: We sought to determine, in a large series of patients with right atrial isomerism, factors associated with mortality. BACKGROUND: Right atrial isomerism is associated with complex congenital heart disease and high morbidity and mortality. METHOD: All data from patients diagnosed with right atrial isomerism between January 1970 and March 1996 were reviewed. RESULTS: A total of 91 consecutive patients (54 male) were identified. Most patients (89%) presented within the first month of life, 62% at birth. Cardiac abnormalities included common atrioventricular (AV) valve (81%), ventricular hypoplasia or single ventricle (73%), abnormal ventriculoarterial connections (96%), pulmonary outflow tract obstruction (84%), anomalous pulmonary venous drainage (87%) and pulmonary vein obstruction (30%). The overall mortality rate was 69%. No interventions were planned or performed in 24%, 95% of whom died. The mortality rate for patients requiring their first cardiovascular operation in the neonatal period was 75% versus 51% for those with later first operations (p < 0.05). The surgical mortality rate for patients undergoing pulmonary vein repair was 95%. Overall survival estimates were 71% at 1 month, 49% at 1 year and 35% at 5 years. Independent risk factors for decreased time to death included the absence of pulmonary outflow obstruction (relative risk [RR] 2.23, p < 0.03), presence of major AV valve anomaly (RR 5.23, p < 0.03) and obstructed pulmonary veins (RR 5.43, p < 0.0001). CONCLUSIONS: Right atrial isomerism continues to have an associated high mortality despite surgical innovations. Management of pulmonary vein obstruction remains a serious problem and is associated with high mortality.

Congenitally corrected transposition of the great arteries in the adult: functional status and complications.

OBJECTIVES: We sought to assess the clinical outcome, functional status and complications of adult patients with congenitally corrected transposition of the great arteries. BACKGROUND: Congenitally corrected transposition is a rare form of congenital heart disease, although survival into adult life may be expected. Little information is available on the long-term prognosis of these patients once they have reached adulthood. This study focuses exclusively on patients >18 years old followed up at a single tertiary referral center. METHODS: The charts of all patients with a diagnosis of congenitally corrected transposition of the great arteries from the Toronto Congenital Cardiac Centre for Adults since 1985 were reviewed. Data were available for 52 patients, 26 of whom had undergone radionuclide angiography. Mortality, clinical and functional status, surgical procedures and complications were reviewed. RESULTS: Thirteen patients (25%) died; age at death was 38.5 +/- 12.5 years (mean +/- SD). The current age of survivors is 32.7 years (range 18.2 to 54.3). Of the survivors, 17 had palliative procedures, and 25 had definitive repair, 11 of whom required reoperation. Left ventricle to pulmonary artery conduit replacement was necessary in seven patients. Eighteen patients have permanent pacemakers, nine of whom developed complete heart block perioperatively. Nine patients developed progressive atrioventricular (AV) block unrelated to operation. Supraventricular arrhythmias occurred in 15 patients. Progressive systemic AV valve regurgitation developed in 10 patients and endocarditis in 6. CONCLUSIONS: Congenitally corrected transposition in the adult patient is not a benign condition. Late complications are common and warrant careful, long-term follow-up.

Mortality in potential arterial switch candidates with transposition of the great arteries.

OBJECTIVES: We reviewed the factors contributing to or causing death before surgery in neonates with d-transposition of the great arteries (TGA) despite anatomy suitable for the arterial switch operation (ASO) to develop strategies to minimize preoperative attrition. BACKGROUND: Currently the ASO for neonates with TGA carries a low operative mortality. However, there is a paucity of information regarding the patients who die before the ASO. Strategies to ensure survival to operation are of importance to improve overall outcome. METHODS: We reviewed all neonates with TGA and patent forearm ovale (PFO) < or = 2 mm, a birthweight <2 kg, or who died before surgery, between 1988 and 1996. RESULTS: We identified 12 out of 295 neonates with TGA (4.1%) with anatomy suitable for the ASO who died prior to surgery. All had TGA/intact ventricular septum (IVS) and presented with a severely restrictive PFO. In 11 of 12 cases the cause of death was attributed to the sequelae of profound hypoxemia from inadequate mixing. Contributing factors were prematurity, 41.7%; severe respiratory distress syndrome, 25%; and persistent pulmonary hypertension of the newborn (PPHN), 16.7%. All patients received prostaglandin E1 (PGE1) infusion. Urgent balloon atrial sepstostomy (BAS) was performed in 66.7% with improved oxygenation. No cases were diagnosed prenatally. In contrast, all patients with a PFO < or = 2 mm who survived to ASO had a significantly better response to PGE1 infusion (p=0.03) than nonsurvivors. The ASO was accomplished without mortality in four of nine with a weight <2 kg. CONCLUSIONS: Of those neonates admitted with TGA, 4.1% died before surgery. Eleven of 12 (3.7%) died due to consequences of inadequate interatrial mixing despite PGE1 infusion. Earlier diagnosis and BAS are critically important in determining survival. Early ASO may improve survival in patients weighing <2 kg. Prenatal diagnosis with delivery in a high-risk obstetrical unit with facilities for immediate BAS and supportive therapy for pulmonary hypertension and ventricular failure may be necessary to salvage this group of patients.

Transesophageal Doppler echocardiography in obstructive hypertrophic cardiomyopathy: clarification of pathophysiology and importance in intraoperative decision making.

To better understand the pathophysiology of obstruction of left ventricular outflow in hypertrophic cardiomyopathy and to determine the value of intraoperative transesophageal Doppler echocardiography in decision making, 32 consecutive patients undergoing ventriculomyectomy were assessed. The mean preoperative left ventricular outflow gradient was 83 +/- 39 mm Hg and the mean basal septal width was 24 +/- 6 mm. Compared with transesophageal findings in 10 normal control subjects, the mitral leaflets were longer and the coaptation point was abnormal in the patients with obstructive hypertrophic cardiomyopathy (anterior and posterior leaflet lengths in the patients were 31 +/- 4 vs. 22 +/- 3 mm in the control group [p less than 0.00001] and 20 +/- 2 vs. 15 +/- 3 mm in the control group [p less than 0.00001]). The coaptation point in the patient group was in the body of the leaflets at a mean of 9 +/- 2 mm from the anterior leaflet tip, whereas it was at or within 3 mm of the leaflet tip in the normal group. During early systole, the distal third to half of the anterior mitral leaflet angled sharply anteriorly and superiorly (systolic anterior motion), resulting in leaflet-septal contact and incomplete mitral leaflet coaptation in mid-systole. This caused the formation of a funnel, composed of the distal parts of both leaflets, that allowed a jet of posteriorly directed mitral regurgitation to occur in mid- and late systole. The sequence of events in systole was eject/obstruct/leak. Transesophageal echocardiography was also helpful in planning the extent of the resection, assessing the immediate result and excluding important complications. In successful cases, the post-myectomy study showed 1) a dramatic thinning of the septum, with widening of the left ventricular outflow tract to a width similar to that in the normal subjects, 2) resolution of systolic anterior motion and the left ventricular outflow tract color mosaic, and marked reduction or abolition of mitral regurgitation despite persistence of abnormal mitral leaflet length and an abnormal mitral leaflet coaptation point. The routine use of transesophageal echocardiography in patients undergoing surgical myectomy for the treatment of obstructive hypertrophic cardiomyopathy is recommended.

Intravascular stent prosthesis for right ventricular outflow obstruction.

OBJECTIVES: This study was designed to assess the impact of implantation of balloon-expandable stents on right ventricular outflow obstruction in children with congenital heart disease. BACKGROUND: Intravascular stenting has been established as a useful treatment in adults with coronary and peripheral vascular disease. Its application in the treatment of infants and children with pulmonary, systemic and right ventricular conduit obstruction resistant to balloon angioplasty is limited. METHODS: A total of 24 stainless steel stents were implanted in 17 patients. Five stents were placed within right ventricular to pulmonary artery conduits, 17 in branch pulmonary arteries and 1 in an aortopulmonary collateral vessel. Follow-up time has ranged from 1 to 14 months, with 6 patients having hemodynamic and angiographic studies greater than 1 year after stent placement. The mean age at implantation was 7.4 +/- 5.6 years and the mean weight 33 +/- 16 kg. RESULTS: Optimal stent position was obtained in 22 of 24 implantations. In one patient the stent slipped from the delivery balloon and was left positioned in the inferior vena cava. No embolization or thrombotic event has been documented. Among patients with right ventricular to pulmonary artery conduit obstruction, the gradient was immediately reduced from 85 +/- 30 mm Hg to 35 +/- 20 mm Hg after stent implantation; however, three patients required conduit replacement because of persistent obstruction with elevated right ventricular pressures (82 +/- 16 mm Hg). In 10 of 11 patients with pulmonary artery stenosis, clinical improvement was noted in association with enlargement of vessel diameter by 92% +/- 90% (range 17% to 355%) and the gradient reduction of 22 +/- 24 mm Hg to 3 +/- 4 mm Hg. CONCLUSIONS: These data support the view that intravascular stenting will become an important adjunct in the management of children with congenital heart disease.

Outcomes of left atrial isomerism over a 28-year period at a single institution.

OBJECTIVES: We determined long-term outcomes in a large cohort with left atrial isomerism (LAI). BACKGROUND: Left atrial isomerism is associated with a complex spectrum of cardiac and noncardiac anomalies that may impact on outcomes. METHODS: The records of all patients with LAI, born between 1970 and 1998, and treated at one center were reviewed. Kaplan-Meier survival was estimated, and independent factors associated with time-related death were identified. RESULTS: There were 163 patients (63% women), and extracardiac anomalies were noted in 36%, including biliary atresia in 10%. Cardiac defects included interrupted inferior caval vein in 92%, anomalous pulmonary veins in 56%, atrioventricular septal defect in 49%, pulmonary atresia or stenosis in 28% and aortic coarctation in 16%, with congenital atrioventricular block in 7%. Of 22 patients with a normal heart, 18% died of extracardiac anomalies. Of 71 patients with hearts suitable for biventricular repair, 62 (87%) had surgery, with survival of 80% at one year, 71% at five years, 66% at 10 years and 63% after 15 years. Of 70 patients with unbalanced cardiac defects suitable for single-ventricle palliation, 47 (67%) had surgery, with survival of 73% at one year, 61% at five years, 53% at 10 years and 48% at 15 years (p < 0.001). Independent factors associated with time-related death included congenital atrioventricular block, aortic coarctation, single ventricle, biliary atresia and other gastrointestinal malformations. CONCLUSIONS: Both cardiac and noncardiac anomalies contribute to a high mortality with LAI. Cardiac transplantation may need to be a considered a primary option for selected high-risk patients.

Pulmonary valve replacement in adults late after repair of tetralogy of fallot: are we operating too late?

OBJECTIVES: The purpose of this study is to evaluate right ventricular (RV) volume and function after pulmonary valve replacement (PVR) and to address the issue of optimal surgical timing in these patients. BACKGROUND: Chronic pulmonary regurgitation (PR) following repair of tetralogy of Fallot (TOF) leads to RV dilation and an increased incidence of sudden cardiac death in adult patients. METHODS: We studied 25 consecutive adult patients who underwent PVR for significant PR late after repair of TOF. Radionuclide angiography was performed in all at a mean of 8.2 months (+/- 8 months) before PVR and repeated at a mean of 28.0 months (+/- 22.8 months) after the operation. Right ventricular (RV) end-systolic volume (RVESV), RV end-diastolic volume (RVEDV) and RV ejection fraction (RVEF) were measured. RESULTS: Mean RVEDV, RVESV and RVEF remained unchanged after PVR (227.1 ml versus 214.9 ml, p = 0.74; 157.4 ml versus 155.4 ml, p = 0.94; 35.6% versus 34.7%, p = 0.78, respectively). Of the 10 patients with RVEF > or = 0.40 before PVR, 5 patients (50%) maintained a RVEF > or = 0.40 following PVR, whereas only 2 out of 15 patients (13%) with pre-operative values <0.40 reached an RVEF > or = 0.40 postoperatively (p < 0.001). CONCLUSIONS: Right ventricular recovery following PVR for chronic significant pulmonary regurgitation after repair of TOF may be compromised in the adult population. In order to maintain adequate RV contractility, pulmonary valve implant in these patients should be considered before RV function deteriorates.

Risk factors for atrial tachyarrhythmias after the Fontan operation.

OBJECTIVES: The purpose of this study was to define the incidence and risk factors for atrial tachyarrhythmias after the Fontan operation. BACKGROUND: Atrial tachyarrhythmias cause morbidity after the Fontan operation. Causative factors may be affected by the type of systemic to pulmonary connection. METHODS: The Fontan operation was performed in 270 consecutive patients between 1982 and 1992. The mean age at operation was 7.0 +/- 4.3 years. Direct atriopulmonary connection was used in 138 patients (51%), total cavopulmonary connection in 94 (35%) and right atrial to right ventricular connection in 38 (14%). RESULTS: Atrial tachyarrhythmias were seen early postoperatively in 55 patients (20%), preoperative atrial tachyarrhythmia being the only risk factor. Follow-up was achieved for 228 early survivors (97%) at a mean interval of 4.4 years. There were 20 late deaths. Late atrial tachyarrhythmias were noted in 29% of patients who received an atriopulmonary connection, 14% of those who received a total cavopulmonary connection and 18% of those who received a right ventricular connection (p < 0.02). Significant risk factors as determined by univariate and multiple logistic regression analysis were atriopulmonary connection type (odds ratio 0.40 for total cavopulmonary relative to atriopulmonary connection [p < 0.05] and 0.37 for right ventricular relative to atriopulmonary connection [p = 0.08]), longer follow-up interval (odds ratio 1.32 for each consecutive year [p < 0.002]) and atrial tachyarrhythmia in the operative period (odds ratio 6.31 [p < 0.0001]). CONCLUSIONS: Early postoperative atrial tachyarrhythmias, length of follow-up and atriopulmonary connection are significant independent risk factors for the presence of late atrial tachyarrhythmias.

Cardiopulmonary function in adult patients late after Fontan repair.

OBJECTIVES: The clinical status and exercise assessment of adult patients late after the Fontan operation were reviewed to determine cardiovascular function. BACKGROUND: The Fontan operation is the final operation for many patients with tricuspid atresia or a single ventricle. Follow-up reports describe most patients to be in Canadian Cardiovascular Society functional class I or II. Objective measures of cardiac performance in the pediatric age group have shown significant dysfunction. METHODS: Forty-seven adult patients were seen late after the Fontan operation at the Toronto Congenital Cardiac Centre for Adults. Thirty of these underwent cycle ergometry to determine maximal exercise capacity. Maximal ventilation, maximal oxygen uptake and anaerobic threshold were determined from a ramp exercise protocol. Ejection fraction at rest and during exercise was measured with gated radionuclide angiography. Results were compared with those of eight normal volunteers. Results are given as mean +/- SD. RESULTS: Thirty patients underwent cardiopulmonary exercise testing 6.7 +/- 3.9 years after a first Fontan operation. Clinically 93% were in functional class I or II. The Fontan group patients had a significantly lower maximal work load (548 +/- 171 vs. 1,094 +/- 190 kilopond-meters, p < 0.00001), anaerobic threshold (11.2 +/- 2.9 vs. 23.6 +/- 4.6 ml/kg per min) and maximal oxygen consumption (14.8 +/- 4.5 vs. 42.1 +/- 10.0 ml/kg per min). Systemic ventricular ejection fraction was lower at rest (38 +/- 12% vs. 58 +/- 7%) and during exercise (40 +/- 15% vs. 70 +/- 8%). CONCLUSIONS: Despite a clinical impression of good function, by objective measures adult patients continue to have significant cardiovascular limitation late after the Fontan operation.

Arrhythmia and mortality after the Mustard procedure: a 30-year single-center experience.

OBJECTIVES: Our purpose was to assess the risk factors for late mortality, loss of sinus rhythm and atrial flutter after the Mustard operation. BACKGROUND: The Mustard operation provides correction of cyanosis with low surgical risk in transposition of the great vessels. However, right ventricular failure, loss of sinus rhythm, atrial flutter and death are frequent long-term complications. METHODS: Records of 534 children who underwent the Mustard operation at a single center since 1962 were reviewed for demographic, anatomic, electrocardiographic and physiologic predictors and outcomes. RESULTS: There were 52 early deaths (9.7%). Survival analysis was undertaken for 478 early survivors with a mean follow-up interval of 11.6 +/- 7.2 years. There were 77 late deaths (16.1%), with sudden death (n = 31) the most frequent cause. Survival estimates were 89% at 5 years and 76% at 20 years of age. Risk factors were an earlier date of operation, operative period arrhythmia and an associated ventricular septal defect. Risk (hazard) of late death declined in the first decade, with further peaks in the second decade. Sinus rhythm was present in 77% at 5 years and 40% at 20 years. Loss of sinus rhythm was associated with previous septectomy, postoperative bradycardia and late atrial flutter. Freedom from atrial flutter was 92% at 5 years and 73% at 20 years of age. Risk factors for atrial flutter were the occurrence of perioperative bradyarrhythmia, reoperation and loss of sinus rhythm during follow-up. Risk of atrial flutter demonstrates a late increase. CONCLUSIONS: Ongoing loss of sinus rhythm and late peaks in the risk of atrial flutter and death necessitate continued follow-up.