Meryl S. Cohen

Hypoplastic Left Heart Syndrome : Current Considerations and Expectations

In the recent era, no congenital heart defect has undergone a more dramatic change in diagnostic approach, management, and outcomes than hypoplastic left heart syndrome (HLHS). During this time, survival to the age of 5 years (including Fontan) has ranged from 50% to 69%, but current expectations are that 70% of newborns born today with HLHS may reach adulthood. Although the 3-stage treatment approach to HLHS is now well founded, there is significant variation among centers. In this white paper, we present the current state of the art in our understanding and treatment of HLHS during the stages of care: 1) pre-Stage I: fetal and neonatal assessment and management; 2) Stage I: perioperative care, interstage monitoring, and management strategies; 3) Stage II: surgeries; 4) Stage III: Fontan surgery; and 5) long-term follow-up. Issues surrounding the genetics of HLHS, developmental outcomes, and quality of life are addressed in addition to the many other considerations for caring for this group of complex patients.

Social Determinants of Risk and Outcomes for Cardiovascular Disease A Scientific Statement From the American Heart Association

An Institute of Medicine report titled U.S. Health in International Perspective: Shorter Lives, Poorer Health documents the decline in the health status of Americans relative to people in other high-income countries, concluding that “Americans are dying and suffering from illness and injury at rates that are demonstrably unnecessary.”1 The report blames many factors, “adverse economic and social conditions” among them. In an editorial in Science discussing the findings of the Institute of Medicine report, Bayer et al2 call for a national commission on health “to address the social causes that have put the USA last among comparable nations.” Although mortality from cardiovascular disease (CVD) in the United States has been on a linear decline since the 1970s, the burden remains high. It accounted for 31.9% of deaths in 2010.3 There is general agreement that the decline is the result, in equal measure, of advances in prevention and advances in treatment. These advances in turn rest on dramatic successes in efforts to understand the biology of CVD that began in the late 1940s.4,5 It has been assumed that the steady downward trend in mortality will continue into the future as further breakthroughs in biological science lead to further advances in prevention and treatment. This view of the future may not be warranted. The prevalence of CVD in the United States is expected to rise 10% between 2010 and 2030.6 This change in the trajectory of cardiovascular burden is the result not only of an aging population but also of a dramatic rise over the past 25 years in obesity and the hypertension, diabetes mellitus, and physical inactivity that accompany weight gain. Although there is no consensus on the precise causes of the obesity epidemic, a dramatic change in the underlying biology of Americans is …

Obesity Is a Common Comorbidity in Children With Congenital and Acquired Heart Disease

OBJECTIVES. Obesity may pose additional cardiovascular risk to children with acquired and congenital heart disease. Many children with heart disease are sedentary as a result of physician-, parent-, and/or self-imposed restrictions. The aim of this study was to evaluate the impact of the epidemic of obesity on children with heart disease. PATIENTS AND METHODS. A cross-sectional review was performed of children evaluated in 2004 at 2 cardiology outpatient clinics. Differences in the prevalence of obese (BMI ≥ 95%) and overweight (BMI 85%–95%) children were compared with national data and healthy control subjects. Dictated letters were reviewed to determine whether obesity was discussed with referring practitioners. RESULTS. Of 2921 patients assessed, 1523 had heart disease. Diagnostic subgroups included “mild” heart disease (n = 401), arrhythmia (n = 447), biventricular repair (n = 511), univentricular palliation (Fontan; n = 108), and heart transplantation (n = 56). More than 25% of the patients with heart disease were obese or overweight; the prevalence of obese and overweight children was significantly lower only in the Fontan group (15.9%). Pediatric cardiologists failed to document obesity or weight counseling in the majority of clinic letters. CONCLUSIONS. Obesity is common in children with congenital and acquired heart disease. Pediatric cardiologists demonstrate inadequate communication regarding this problem to referring practitioners. Healthy-lifestyle counseling and routine exercise in children with heart disease may be underemphasized.

Morphometric analysis of unbalanced common atrioventricular canal using two-dimensional echocardiography

OBJECTIVES This study was designed to define morphometric echocardiographic variables of unbalanced common atrioventricular canal (CAVC) that could aid in appropriate referral for surgical repair. BACKGROUND Unbalanced CAVC has a high surgical mortality rate. This may be secondary to inappropriate referral of some patients for two-ventricle repair (closure of septal defects) instead of single-ventricle repair (Norwood palliation and Fontan operation). METHODS The echocardiograms of 103 patients with CAVC were retrospectively reviewed. In the subcostal left anterior oblique view, the area of the atrioventricular (AV) valve aportioned over each ventricle was measured, and an AV valve index (AVVI) was calculated as left/right valve area. The ventricular cavity ratio between the two ventricles was estimated as left ventricular length times width divided by right ventricular length times width. These variables were correlated with surgical referral and outcome. RESULTS Patients previously categorized as having balanced CAVC all had AVVI > 0.67 (n = 77). Of the patients with unbalanced CAVC (n = 26), 11 had ductal-dependent circulation and underwent Norwood palliation (AVVI 0.21 +/- 0.13, mean +/- SD), and 15 had two-ventricle repair (AVVI 0.51 +/- 0.12, p < 0.0001). Of these 15 patients, 9 have survived, with no difference in mean AVVI between survivors and nonsurvivors (0.52 +/- 0.11 versus 0.49 +/- 0.13, p = 0.72). For all 103 patients, AVVI correlated with ventricular cavity ratio. However, of the unbalanced CAVC group who underwent two-ventricle repair, three nonsurvivors had a discrepancy between AVVI and ventricular cavity ratio (low AVVI but normal ventricular size). A large ventricular septal defect was present in all six nonsurvivors but in only four of nine survivors (p < 0.05). CONCLUSIONS Echocardiographic morphometry is useful in defining unbalance in CAVC. If AVVI is < 0.67 in the presence of a large ventricular septal defect, a single-ventricle approach to repair should be considered.

Idebenone in Friedreich ataxia cardiomyopathy—results from a 6-month phase III study (IONIA)

BACKGROUND Friedreich ataxia (FRDA) is commonly associated with hypertrophic cardiomyopathy, but little is known about its frequency, severity, or treatment. In this 6-month randomized, double-blind, controlled study, we sought to determine whether idebenone improves cardiac measures in FRDA. METHODS Seventy pediatric subjects were treated either with idebenone (450/900 mg/d or 1,350/2,250 mg/d) or with placebo. Electrocardiograms (ECGs) were assessed at each visit, and echocardiograms, at baseline and week 24. RESULTS We found ECG abnormalities in 90% of the subjects. On echocardiogram, 81.4% of the total cohort had left ventricular (LV) hypertrophy, as measured by increased LV mass index-Dubois, and the mean ejection fraction (EF) was 56.9%. In linear regression models, longer PR intervals at baseline were marginally associated with longer GAA repeat length (P = .011). Similarly, GAA repeat length did not clearly predict baseline EF (P = .086) and LV mass by M-mode (P = .045). Left ventricular mass index, posterior wall thickness, EF, and ECG parameters were not significantly improved by treatment with idebenone. Some changes in echocardiographic parameters during the treatment phase correlated with baseline status but not with treatment group. CONCLUSIONS Idebenone did not decrease LV hypertrophy or improve cardiac function in subjects with FRDA. The present study does not provide evidence of benefit in this cohort over a 6-month treatment period.

Guidelines for the Echocardiographic Assessment of Atrial Septal Defect and Patent Foramen Ovale: From the American Society of Echocardiography and Society for Cardiac Angiography and Interventions

Target Audience 911 Objectives 91

Neo-aortic root dilation and valve regurgitation up to 21 years after staged reconstruction for hypoplastic left heart syndrome.

OBJECTIVES We sought to assess the prevalence and progression of neo-aortic root dilation and valvar regurgitation after staged reconstruction for hypoplastic left heart syndrome (HLHS). BACKGROUND In HLHS, the pulmonary valve functions as the neo-aortic valve. Neo-aortic valve dysfunction has been observed after arterial switch operation and the Ross procedure. METHODS Patients with HLHS born before January 1995 who had the Fontan operation and had serial echocardiograms were included. Echocardiograms were reviewed preoperatively, after each surgical reconstruction, and at most recent follow-up for neo-aortic root size and severity of neo-aortic regurgitation (AR). Potential risk factors for neo-aortic valve dysfunction were assessed. RESULTS Fifty-three patients met inclusion criteria. Bidirectional superior cavopulmonary anastomosis as an interim procedure was performed in 39 patients (74%). Median duration of follow-up was 9.2 (range 5.1 to 21) years. During follow-up, the neo-aortic root progressively dilated out of proportion to body size over time, with 52 patients (98%) having a Z-score >2 at most recent follow-up. Neo-AR was present in 61% of patients at most recent follow-up, with progression over time in 26 patients (49%). However, neo-AR was more than mild in only three patients. Significantly larger neo-aortic root Z-scores were observed in patients with any degree of neo-AR at most recent follow-up. No other anatomic or clinical variables correlated with severity of neo-AR or root dilation. CONCLUSIONS After staged reconstruction for HLHS, neo-aortic root dilation and neo-AR progress over time. Early volume unloading does not have a beneficial impact on dilation of the neo-aortic root. These findings raise concerns about neo-aortic valve function into adulthood.

Acute Cardiovascular Effects of Fetal Surgery in the Human

Background—Prenatal surgery for congenital anomalies can prevent fetal demise or alter the course of organ development, resulting in a more favorable condition at birth. The indications for fetal surgery continue to expand, yet little is known about the acute sequelae of fetal surgery on the human cardiovascular system. Methods and Results—Echocardiography was used to evaluate the heart before, during, and early after fetal surgery for congenital anomalies, including repair of myelomeningocele (MMC, n=51), resection of intrathoracic masses (ITM, n=15), tracheal occlusion for congenital diaphragmatic hernia (CDH, n=13), and resection of sacrococcygeal teratoma (SCT, n=4). Fetuses with MMC all had normal cardiovascular systems entering into fetal surgery, whereas those with ITM, CDH, and SCT all exhibited secondary cardiovascular sequelae of the anomaly present. At fetal surgery, heart rate increased acutely, and combined cardiac output diminished at the time of fetal incision for all groups including those with MMC, which suggests diminished stroke volume. Ventricular dysfunction and valvular dysfunction were identified in all groups, as was acute constriction of the ductus arteriosus. Fetuses with ITM and SCT had the most significant changes at surgery. Conclusions—Acute cardiovascular changes take place during fetal surgery that are likely a consequence of the physiology of the anomaly and the general effects of surgical stress, tocolytic agents, and anesthesia. Echocardiographic monitoring during fetal surgery is an important adjunct in the management of these patients.

Hepatic pathology may develop before the Fontan operation in children with functional single ventricle: An autopsy study

OBJECTIVE Liver fibrosis has emerged as an important long-term complication of the Fontan operation. We aimed to describe liver histology at autopsy in patients who had undergone the Fontan operation and to determine whether patient variables are associated with the degree of fibrosis. METHODS A review was performed of all patients with a history of the Fontan operation who died and underwent autopsy at our institution from 1980 to 2009. Autopsy liver slides were evaluated independently by 2 pathologists. RESULTS Twenty-two patients were studied. The median interval between Fontan and death was 20 days (range, 1 day-17.5 years). Portal fibrosis was observed in 20 (91%) patients and sinusoidal fibrosis was observed in 17 (77%) patients. Using simple linear regression, time from the Fontan operation was significantly associated with the degree of portal fibrosis on Ishak (P = .03) and modified Scheuer fibrosis (P = .02) scales. Significant portal fibrosis was observed in 8 (57%) of the 14 patients who died 30 days or less after the Fontan operation. In these 14 patients, severity of portal fibrosis was associated with length of hospitalization after pre-Fontan cardiac operations (P = .03) and pre-Fontan mean right atrial pressure (P = .04). CONCLUSIONS At autopsy, hepatic fibrosis was commonly observed in patients who had undergone the Fontan operation. Portal fibrosis has been previously unrecognized in this population. Significant portal fibrosis occurred in most who died soon after the Fontan procedure and was associated with pre-Fontan morbidity. Hepatic disease in the single-ventricle population is multifactorial and may begin before the Fontan operation.

Atrioventricular valve regurgitation in patients with single ventricle: impact of the bidirectional cavopulmonary anastomosis

BACKGROUND It is not known whether atrioventricular valve regurgitation (AVVR) can improve in some patients after the bidirectional cavopulmonary anastomosis (BCPA) without undertaking concomitant valvuloplasty. METHODS We retrospectively reviewed our experience with patients who underwent the BCPA between June 1989 and June 2000 with specific attention to those patients with moderate or severe AVVR. The degree of AVVR was determined by color Doppler echocardiography. During the study period there were 576 patients who underwent BCPA at a median age of 6.8 months (range, 1.3 months to 4.8 years). The majority of subjects (66%) had a tricuspid valve as the systemic atrioventricular valve. Significant (moderate or severe) AVVR before BCPA was noted in 36 of 576 patients (6%) and was significantly more prevalent (8 of 52 patients, 15%; p = 0.01) in patients with a common atrioventricular canal. RESULTS Of the 36 subjects with moderate or severe AVVR, 8 had interventions (6 valvuloplasty, 2 aortic arch dilation) at BCPA. There was 1 hospital death (2.8%). Of the remaining 27 survivors who did not undergo additional interventions at BCPA, improvement in AVVR (mild or none) was noted in 6 (22%) at intermediate follow-up (median, 2 years; range, 0.5 to 3.1 years). The presence of significant AVVR before BCPA was not significantly associated with hospital survival or intermediate-term freedom from death or transplantation. CONCLUSIONS We conclude that AVVR improves in some patients after BCPA and that valvuloplasty is not justified in all patients with moderate preoperative AVVR.