Lynne E. Nield

Repeated systematic surveillance of Kawasaki disease in Ontario from 1995 to 2006

Background:  Rising incidences of Kawasaki disease (KD) have been reported worldwide. Reported herein are the results of 4 triennial KD surveillances conducted in Ontario.

Outcomes for children with cardiomyopathy awaiting transplantation.

OBJECTIVE To determine factors associated with outcomes after listing for transplantation in children with cardiomyopathies. BACKGROUND Childhood cardiomyopathies form a heterogeneous group of diseases, and in many, the prognosis is poor, irrespective of the etiology. When profound heart failure develops, cardiac transplantation can be the only viable option for survival. METHODS We included all children with cardiomyopathy listed for transplantation between 12/89 and 4/98 in this historical cohort study. RESULTS We listed 31 patients, 15 male and 16 female, 27 with dilated and 4 with restrictive cardiomyopathy, for transplantation. The median age at listing was 5.7 years, with a range from fetal life to 17.8 years. Transplantation was achieved in 23 (74%), with a median interval from listing of 54 days, and a range from zero to 11.4 years. Of the patients, 14 were transplanted within 30 days of listing. Five patients (16%) died before transplantation. Within the Canadian algorithm, one of these was in the third state, and four in the fourth state. One patient was removed from the list after 12 days, having recovered from myocarditis, and two remain waiting transplantation after intervals of 121 and 476 days, respectively. Patients who died were more likely to be female (5/5 vs. 11/26; p=0.04) and to have been in the third or fourth states at listing (5/5 vs. 15/26; p=0.04). The use of mechanical ventricular assistance, in 10 patients, was not a predictor of an adverse outcome. While not statistically significant, survival to transplantation was associated with treatment using inhibitors of angiotensin converting enzyme, less mitral regurgitation, a higher mean ejection fraction and cardiac index, and lower right ventricular systolic pressure. CONCLUSIONS Children with cardiomyopathy awaiting transplantation have a mortality of 16% related to their clinical state at the time of listing.

Outcomes of prenatally diagnosed tetralogy of Fallot: Implications for valve-sparing repair versus transannular patch

OBJECTIVES To assess outcomes of prenatally diagnosed tetralogy of Fallot and determine factors associated with the choice to undergo a valvesparing repair versus transannular patch, and the use of prostaglandins at birth. METHODS All cases at The Hospital for Sick Children (Toronto, Ontario) with a fetal diagnosis of tetralogy of Fallot from 1998 to 2006, were reviewed for demographic and fetal echocardiographic data to determine factors associated with the valve-sparing repair and need for perinatal support. RESULTS Sixty-four fetuses met inclusion criteria (median gestational age 22 weeks) with 47 live births. Twenty-six underwent valve-sparing repair (median age 5.7 months) and 14 underwent transannular patch repair (median age 4.5 months). There were seven deaths before surgery and one post-transannular patch repair. One patient required a transannular patch repair after the initial valve-sparing repair. Twelve of 29 (41%) patients received prostaglandins at birth. Type of surgical repair, use of prostaglandins and postnatal death were among the outcomes investigated. The mean pulmonary valve (PV) z-score was -3.0+/-2.0 and the mean PV/aortic valve (AoV) ratio was 0.65+/-0.10. Lower PV z-score (P=0.04), smaller PV/AoV ratio (P=0.04) and the presence of nonantegrade arterial duct flow (P=0.02) were associated with prostaglandin use. A higher PV/AoV ratio was associated with valvesparing repair (P=0.04). Fetal z-scores of the PV, AoV and right pulmonary artery at 29 to 32 weeks gestational age correlated with respective postnatal z-scores (P=0.01). CONCLUSION Fetal echocardiographic variables were associated with the use of prostaglandins and valve-sparing repair in fetuses with tetralogy of Fallot, and at 29 weeks, correlated with postnatal valve diameters.

Outcome of Fetuses and Infants With Double Inlet Single Left Ventricle

Double-inlet left ventricle (DILV) includes a diverse range of anatomic variables that affect the surgical strategy. The aim of this study was to determine the impact of anatomic subtype, associated anomalies, and fetal diagnosis on the management and outcomes of fetuses and infants with DILV. The outcomes of fetuses and infants with DILV diagnosed from 1990 to 2004 at 3 major referral centers were reviewed. Sixty-five cases of DILV were detected prenatally. Twenty-one of these pregnancies were terminated, including 17 of 37 (46%) in which the diagnoses were made at < or =24 weeks of gestation. An additional 106 patients were diagnosed with DILV within the first 3 months of life. The percentage of patients diagnosed prenatally increased significantly over the study period. Transplantation-free survival was 88%, 82%, 79%, and 76% at 1 month, 1 year, 5 years, and 10 years, respectively. Factors associated with improved survival in univariate analysis included year of birth after 1994, no neonatal Norwood or Damus procedure, and no neonatal surgery at all. In multivariate analysis, any neonatal surgery was the only factor associated with worse survival. Associated anomalies and prenatal diagnosis were not associated with postnatal outcome. In conclusion, although the frequency of prenatal diagnosis of DILV has increased significantly over the past 15 years, prenatal diagnosis is not associated with better postnatal survival. During this same period, postnatal survival has improved substantially. Neonatal surgery of any type was the only independent risk factor for worse survival.

Spectrum and Outcome of Primary Cardiomyopathies Diagnosed During Fetal Life

OBJECTIVES The purpose of this study was to determine the phenotypic presentation, causes, and outcome of fetal cardiomyopathy (CM) and to identify early predictors of outcome. BACKGROUND Although prenatal diagnosis is possible, there is a paucity of information about fetal CM. METHODS This was a retrospective review of 61 consecutive fetal cases with a diagnosis of CM at a single center between 2000 and 2012. RESULTS Nonhypertrophic CM (NHCM) was diagnosed in 40 and hypertrophic CM (HCM) in 21 fetuses at 24.7 ± 5.7 gestational weeks. Etiologies included familial (13%), inflammatory (15%), and genetic-metabolic (28%) disorders, whereas 44% were idiopathic. The pregnancy was terminated in 13 of 61 cases (21%). Transplantation-free survival from diagnosis to 1 month and 1 year of life for actively managed patients was better in those with NHCM (n = 31; 58% and 58%, respectively) compared with those with HCM (n = 17; 35% and 18%, respectively; hazard ratio [HR]: 0.44; 95% confidence interval [CI]: 0.12 to 0.72; p = 0.007). Baseline echocardiographic variables associated with mortality in actively managed patients included ventricular septal thickness (HR: 1.21 per z-score increment; 95% CI: 1.07 to 1.36; p = 0.002), cardiothoracic area ratio (HR: 1.06 per percent increment; 95% CI: 1.02 to 1.10; p = 0.006), ≥3 abnormal diastolic Doppler flow indexes (HR: 1.44; 95% CI: 1.07 to 1.95; p = 0.02), gestational age at CM diagnosis (HR: 0.91 per week increment; 95% CI: 0.83 to 0.99; p = 0.03), and, for fetuses in sinus rhythm, a lower cardiovascular profile score (HR: 1.45 per point decrease; 95% CI: 1.16 to 1.79; p = 0.001). CONCLUSIONS Fetal CM originates from a broad spectrum of etiologies and is associated with substantial mortality. Early echocardiographic findings appear useful in predicting adverse perinatal outcomes.

Comparison of Impact of Prenatal Versus Postnatal Diagnosis of Congenitally Corrected Transposition of the Great Arteries

Congenitally corrected transposition of the great arteries (CCTGA) in the absence of major cardiac anomalies is thought to have a good outcome, although this has not been well documented. The objective of the present study was to compare the characteristics and outcomes of patients with a prenatal diagnosis of CCTGA to the characteristics and outcomes of those diagnosed postnatally. The optimal outcome was defined as intervention-free survival. All patients with CCTGA diagnosed prenatally and postnatally from 1999 to 2006 at 2 tertiary care institutions were reviewed. Patients with a single ventricle, heterotaxy, or valvar atresia were excluded. The differences between groups were assessed using the t test and chi-square test. A total of 54 patients (16 prenatal with 14 live born and 39 postnatal) were included. The patients diagnosed prenatally were diagnosed at a median gestational age of 20 weeks (range 16 to 37). Two deaths in each group were due to heart failure. The intervention-free survival rate for the prenatal and postnatal groups at 1, 6, and 36 months was 79%, 45%, and 30% and 85%, 61%, and 23%, respectively (p = NS). Of 37 patients, 14 (38%) underwent an arterial switch plus atrial baffling so that the morphologic left ventricle supported the systemic circulation, and 6 (16%) underwent repair of associated lesions so the morphologic right ventricle supported the systemic circulation; 4 (11%) of the 37 patients had pacemaker only. Prenatal patients with >1 fetal echocardiogram (12 of 14) did not have progression before birth. In conclusion, CCTGA has a >70% risk of intervention in the first 3 years after birth. The outlook is guarded and has an important effect on prenatal counseling.

Impact of prenatal diagnosis and anatomical subtype on outcome in double outlet right ventricle

BACKGROUND We sought to investigate the influence of prenatal diagnosis and risk factors for adverse outcomes in double outlet right ventricle (DORV) not associated with heterotaxy. METHODS Patients with a pre or postnatal diagnosis of DORV from 2000 to 2007 were identified and classified into 3 subgroups: subaortic ventricular septal defect (VSD) and normal great artery (GA) arrangement (=VSD type), tetralogy of Fallot type, and transposition of the GA type (=TGA type). Patients with heterotaxy, atrioventricular septal defect, valve atresia, and ventricular hypoplasia were excluded. Complex postnatal care was defined as prematurity, need for prostaglandins, surgical repair <2 months, or univentricular palliation. Risk factors for complex postnatal care and demise were sought in multivariable logistic regression models. One hundred fort-five patients were included (93 prenatal, 52 postnatal). RESULTS There were 24 pregnancy terminations and 7 in utero deaths. Fetal demise was associated with abnormal karyotype (odds ratio [OR] 1.9, P = .01), any tricuspid valve regurgitation (OR 10.6, P = .01), and hydrops (OR 23.8, P = .02). Of 114 liveborn patients, 23 were tetralogy-type, 67 VSD-type, and 24 TGA-type patients. Postnatal survival of liveborn patients at 1 year was similar in pre- versus postnatally diagnosed patients (84% vs 85%). Abnormal GA relationship (OR 2.9, P = .02), subpulmonary VSD (OR 6.0, P = .001), unobstructed pulmonary blood flow at birth (OR 2.8, P = .05), and aortic coarctation (OR 9.0, P = .007) were associated with suboptimal postsurgical outcomes. CONCLUSION Double outlet right ventricle, even without heterotaxy, is associated with complex postnatal care and high risk of early demise. Morphologic subtype, irrespective of pre- or postnatal diagnosis, is a major determinant of outcome.

Intraoperative coronary artery pulse Doppler patterns in patients with complete transposition of the great arteries undergoing the arterial switch operation

BACKGROUND Arterial switch operation is standard repair for complete transposition of the great arteries (TGA). Coronary artery abnormalities are the most common cause of morbidity and mortality in the acute postoperative phase. This study was designed to determine whether coronary artery pulse Doppler flow patterns obtained by transesophageal echocardiography during the arterial switch operation are correlated with acute postoperative outcomes. METHODS A retrospective review of all patients with TGA undergoing the arterial switch operation between 2004 and 2006 was performed. Intraoperative coronary artery pulse Doppler flow patterns were analyzed by 2 blinded investigators. Associations of coronary artery pulse Doppler flow patterns with clinical outcomes were sought using multivariable linear and logistic regression analysis. RESULTS Sixty-three patients (48 male, gestational age 38 +/- 2 weeks, birth weight 3,514 +/- 613 g) were analyzed. Three patients needed mechanical support (2 died), 19 had delayed sternal closure, 17 had arrhythmias, and 9 had ST changes. The most common coronary artery pulse Doppler flow pattern consisted of a late systolic peak followed by low-velocity flow throughout diastole. A left main coronary artery (LMCA) velocity time integral >0.14 (P = .01) and an LMCA peak systolic velocity >0.6 cm/s (P = .05) were associated with need for surgical revision. CONCLUSION Abnormalities in LMCA flow were associated with the need for surgical revision in patients with TGA undergoing the arterial switch operation. Normal coronary artery pulse Doppler flow patterns after the arterial switch operation consisted of a late systolic peak followed by low-velocity flow throughout diastole.

Clinical Review of Obstructive Primary Cardiac Tumors in Childhood

OBJECTIVES This study aims to examine the long-term outcomes of conservative management compared with surgical resection for obstructive and nonobstructive primary cardiac tumors in children. DESIGN A 20-year retrospective review of primary cardiac tumors seen in the right ventricular outflow tract (RVOT) and left ventricular outflow tract (LVOT) in children at The Hospital for Sick Children, Toronto, Canada. Students t-tests and Fishers exact chi-square were used to compare outcomes between the conservatively managed vs. surgical resection groups and the obstructive vs. nonobstructive tumor groups. RESULTS Between 1990 and 2010, we identified 130 children with intracardiac tumors among 52 937 (2.5 per 1000 children, 95th confidence interval: 2.1-2.9 per 1000). Thirty-six children (28%) had at least one cardiac tumor in the RVOT (n = 13) or LVOT (n = 23). Of those, 14 children had peak outflow gradients of >20 mm Hg at the diagnostic echocardiogram (median age at diagnosis: 4 days, range 0 days-6 months; mean follow-up: 7.8 ± 4.5 years). Rhabdomyoma was the most common tumor 27/36 (75%). Twelve (33%) patients underwent surgical repair vs. 24 patients who were observed only. There was no difference in survival. Patients who had surgery tended to be sicker (intubated at diagnosis 4/12, 33% vs. 1/23, 4%, P = .04). There were no deaths in either group. One child required reoperation for severe aortic insufficiency, and only one child in the observation group had residual obstruction at most recent follow-up. CONCLUSIONS Primary cardiac tumors in childhood obstructing the RVOT or LVOT are uncommon findings after birth and may be managed nonsurgically in most cases.

Does prenatal diagnosis of hypoplastic left heart syndrome make a difference? – A systematic review

Hypoplastic left heart syndrome is frequently diagnosed prenatally with variable benefit. We performed a systematic review to evaluate the impact of fetal diagnosis; the primary objective was to evaluate impact on mortality.