Jamil Aboulhosn

Arrhythmia Burden in Adults With Surgically Repaired Tetralogy of Fallot A Multi-Institutional Study

Background— The arrhythmia burden in tetralogy of Fallot, types of arrhythmias encountered, and risk profile may change as the population ages. Methods and Results— The Alliance for Adult Research in Congenital Cardiology (AARCC) conducted a multicenter cross-sectional study to quantify the arrhythmia burden in tetralogy of Fallot, to characterize age-related trends, and to identify associated factors. A total of 556 patients, 54.0% female, 36.8±12.0 years of age were recruited from 11 centers. Overall, 43.3% had a sustained arrhythmia or arrhythmia intervention. Prevalence of atrial tachyarrhythmias was 20.1%. Factors associated with intraatrial reentrant tachycardia in multivariable analyses were right atrial enlargement (odds ratio [OR], 6.2; 95% confidence interval [CI], 2.8 to 13.6), hypertension (OR, 2.3; 95% CI, 1.1 to 4.6), and number of cardiac surgeries (OR, 1.4; 95% CI, 1.2 to 1.6). Older age (OR, 1.09 per year; 95% CI, 1.05 to 1.12), lower left ventricular ejection fraction (OR, 0.93 per unit; 95% CI, 0.89 to 0.96), left atrial dilation (OR, 3.2; 95% CI, 1.5 to 6.8), and number of cardiac surgeries (OR, 1.5; 95% CI, 1.2 to 1.9) were jointly associated with atrial fibrillation. Ventricular arrhythmias were prevalent in 14.6% and jointly associated with number of cardiac surgeries (OR, 1.3; 95% CI, 1.1 to 1.6), QRS duration (OR, 1.02 per 1 ms; 95% CI, 1.01 to 1.03), and left ventricular diastolic dysfunction (OR, 3.3; 95% CI, 1.5 to 7.1). Prevalence of atrial fibrillation and ventricular arrhythmias markedly increased after 45 years of age. Conclusions— The arrhythmia burden in adults with tetralogy of Fallot is considerable, with various subtypes characterized by different profiles. Atrial fibrillation and ventricular arrhythmias appear to be influenced more by left- than right-sided heart disease.

Left Ventricular Outflow Obstruction Subaortic Stenosis, Bicuspid Aortic Valve, Supravalvar Aortic Stenosis, and Coarctation of the Aorta

Left ventricular outflow tract obstructions (LVOTOs) encompass a series of stenotic lesions starting in the anatomic left ventricular outflow tract (LVOT) and stretching to the descending portion of the aortic arch (Figure 1). Obstruction may be subvalvar, valvar, or supravalvar. These obstructions to forward flow may present alone or in concert, as in the frequent association of a bicuspid aortic valve with coarctation of the aorta. All of these lesions impose increased afterload on the left ventricle and, if severe and untreated, result in hypertrophy and eventual dilatation and failure of the left ventricle. LVOTOs are congenital in the vast majority of individuals younger than 50 years in the United States; some variants of subaortic obstruction are the exception. It is imperative to consider all patients with LVOTO at a high risk for developing infective endocarditis, and one should always institute appropriate measures for prophylaxis. The present article is intended as a contemporary review of the causes, manifestations, treatments, and outcomes of LVOTO; it will not address LVOTO in the pediatric population or genetic hypertrophic cardiomyopathy but will focus strictly on congenital malformations in the adult. Figure 1. Artist’s rendering of the LVOTO lesions in sequence as viewed from a superolateral orientation. A, Gradient echo cardiac MR image as viewed from the frontal projection demonstrating flow acceleration at a site of supravalvar aortic stenosis (white arrow) in a patient with Williams syndrome. The black arrow identifies the level of the unrestricted aortic valve. B, Classic radiological signs of coarctation of the aorta: rib notching (white arrows) as seen on a posteroanterior chest x-ray in a patient with coarctation of the aorta. The rib notching is caused by erosion of the inferior rib margins by dilated pulsatile posterior intercostals collateral arteries. The black arrow points to the Figure 3 silhouette that …

Prevalence of Left Ventricular Systolic Dysfunction in Adults With Repaired Tetralogy of Fallot

Left ventricular (LV) systolic dysfunction has been observed in patients with repaired tetralogy of Fallot (TOF), although its clinical associations are unknown. Adults with repaired TOF were identified from 11 adult congenital heart disease centers. Clinical history was reviewed. Patients with pulmonary atresia were excluded. Echocardiograms were reanalyzed to estimate LV ejection fraction. LV function was defined as normal (LV ejection fraction ≥ 55%) or mildly (45% to 54%), moderately (35% to 44%), or severely (< 35%) decreased. Right ventricular (RV) and LV dimensions and Doppler parameters were remeasured. Function of all valves was qualitatively scored. Of 511 patients studied, LV systolic dysfunction was present in 107 (20.9%, 95% confidence interval 17.4 to 24.5). Specifically, 74 (14.4%) had mildly decreased and 33 (6.3%) had moderately to severely decreased systolic function. Presence of moderate to severe LV dysfunction was associated with male gender, LV enlargement, duration of shunt before repair, history of arrhythmia, QRS duration, implanted cardioverter-defibrillator, and moderate to severe RV dysfunction. Severity or duration of pulmonary regurgitation was not different. In conclusion, LV systolic dysfunction was found in 21% of adult patients with TOF and was associated with shunt duration, RV dysfunction, and arrhythmia.

Aortic Root Dilatation in Adults with Surgically Repaired Tetralogy of Fallot A Multicenter Cross-Sectional Study

Background— Although aortic root pathology has been described in patients with tetralogy of Fallot, the scope of the problem remains poorly defined. We sought to determine the prevalence and predictors of aortic root dilatation in adults with repaired tetralogy of Fallot. Methods and Results— A multicenter cross-sectional study was conducted with standardized reassessment of echocardiographic parameters in 474 adults (≥18 years) with surgically repaired tetralogy of Fallot or pulmonary atresia with ventricular septal defect. The aortic root was measured in a parasternal long-axis view, in diastole, at the level of the sinus of Valsalva. Prevalence and predictors of an absolute diameter ≥40 mm and of an observed-to-expected ratio >1.5 were assessed. The aortic root dimension was ≥40 mm in 28.9% (95% confidence interval, 26.9%–30.9%). In multivariate analyses, the only independently associated factor was male sex (odds ratio, 4.48; 95% confidence interval, 1.55–12.89; P=0.006). The prevalence of an observed-to-expected aortic root dimension ratio >1.5 was 6.6% (95% confidence interval, 5.3%–7.9%). It was associated with pulmonary atresia and moderate or severe aortic regurgitation in univariate analyses, but no independent predictor was identified. The side of the aortic arch was not associated with aortic root dimension. The prevalence of moderate or severe aortic regurgitation was 3.5% (95% confidence interval, 2.7%–4.2%). Conclusions— Although nearly one third of adults with repaired tetralogy of Fallot have an aortic root diameter ≥40 mm, the prevalence of a dilated aortic root, when defined by an indexed ratio of observed-to-expected values, is low. Similarly, moderate or severe aortic regurgitation is uncommon.

The CALF (Congenital Heart Disease in Adults Lower Extremity Systemic Venous Health in Fontan Patients) study.

OBJECTIVES The objective of this study was to document the prevalence of chronic venous insufficiency (CVI) and its associated factors in adults with Fontan physiology. BACKGROUND As the population of adults with complex congenital heart disease and Fontan physiology increases, so does the occurrence of highly morbid and mortal outcomes, including heart failure and thromboembolism. The presence of abnormal peripheral hemodynamic conditions in this population and their potential contribution to adverse outcomes is not well known. The primary objective of this study was to document the prevalence of CVI in adults with Fontan physiology. METHODS A total of 159 adults with Fontan physiology from 7 adult congenital heart centers were prospectively assessed for lower extremity CVI, with the assignment of clinical, etiological, anatomical, and pathophysiological classification grades, and compared with age-matched and sex-matched controls. Leg photographs were independently reassessed to confirm interobserver reliability. RESULTS The prevalence of CVI was significantly greater in the Fontan population (60%; 95% confidence interval [CI]: 52% to 68%) compared with healthy controls (32%; 95% CI: 15% to 54%) (p = 0.008). Strikingly, the prevalence of severe CVI (clinical, etiological, anatomical, and pathophysiological grade > or = 4) was significantly higher in the Fontan group (22%; 95% CI: 16% to 29%) versus the healthy controls (0%; 95% CI: 0% to 14%) (p = 0.005). In a multivariate analysis, several factors were independently associated with severe CVI, including increased numbers of catheterizations with groin venous access, lower extremity itching, and deep venous thrombosis. CONCLUSIONS CVI is common in adult patients with congenital heart disease with Fontan physiology. The contribution of abnormal peripheral hemodynamic conditions to comorbidities, including thromboembolism and heart failure, and interventions to improve peripheral hemodynamic conditions require further exploration.

Transcatheter Tricuspid Valve-in-Valve Implantation for the Treatment of Dysfunctional Surgical Bioprosthetic Valves: An International, Multicenter Registry Study.

Background— Off-label use of transcatheter aortic and pulmonary valve prostheses for tricuspid valve-in-valve implantation (TVIV) within dysfunctional surgical tricuspid valve (TV) bioprostheses has been described in small reports. Methods and Results— An international, multicenter registry was developed to collect data on TVIV cases. Patient-related factors, procedural details and outcomes, and follow-up data were analyzed. Valve-in-ring or heterotopic TV implantation procedures were not included. Data were collected on 156 patients with bioprosthetic TV dysfunction who underwent catheterization with planned TVIV. The median age was 40 years, and 71% of patients were in New York Heart Association class III or IV. Among 152 patients in whom TVIV was attempted with a Melody (n=94) or Sapien (n=58) valve, implantation was successful in 150, with few serious complications. After TVIV, both the TV inflow gradient and tricuspid regurgitation grade improved significantly. During follow-up (median, 13.3 months), 22 patients died, 5 within 30 days; all 22 patients were in New York Heart Association class III or IV, and 9 were hospitalized before TVIV. There were 10 TV reinterventions, and 3 other patients had significant recurrent TV dysfunction. At follow-up, 77% of patients were in New York Heart Association class I or II (P<0.001 versus before TVIV). Outcomes did not differ according to surgical valve size or TVIV valve type. Conclusions— TVIV with commercially available transcatheter prostheses is technically and clinically successful in patients of various ages across a wide range of valve size. Although preimplantation clinical status was associated with outcome, many patients in New York Heart Association class III or IV at baseline improved. TVIV should be considered a viable option for treatment of failing TV bioprostheses.

The care of adults with congenital heart disease across the globe: Current assessment and future perspective: A position statement from the International Society for Adult Congenital Heart Disease (ISACHD)

The number of adults with congenital heart disease (CHD) has increased markedly over the past few decades as a result of astounding successes in pediatric cardiac care. Nevertheless, it is now well understood that CHD is not cured but palliated, such that life-long expert care is required to optimize outcomes. All countries in the world that experience improved survival in CHD must face new challenges inherent to the emergence of a growing and aging CHD population with changing needs and medical and psychosocial issues. Founded in 1992, the International Society for Adult Congenital Heart Disease (ISACHD) is the leading global organization of professionals dedicated to pursuing excellence in the care of adults with CHD worldwide. Recognizing the unique and varied issues involved in caring for adults with CHD, ISACHD established a task force to assess the current status of care for adults with CHD across the globe, highlight major challenges and priorities, and provide future direction. The writing committee consisted of experts from North America, South America, Europe, South Asia, East Asia, and Oceania. The committee was divided into subgroups to review key aspects of adult CHD (ACHD) care. Regional representatives were tasked with investigating and reporting on relevant local issues as accurately as possible, within the constraints of available data. The resulting ISACHD position statement addresses changing patterns of worldwide epidemiology, models of care and organization of care, education and training, and the global research landscape in ACHD.

Transconduit puncture for catheter ablation of atrial tachycardia in a patient with extracardiac Fontan palliation

The Fontan palliation and its variants are the most widely used and accepted approach to regulate pulmonary blood flow and relieve cyanosis in patients with single ventricle physiology1. First generation Fontan procedures involved connection of the right atrium (RA) to the pulmonary artery (PA). However, this frequently caused RA dilation, sluggish RA flow, atrial fibrosis, and was associated with a high incidence of atrial arrhythmias2,3. Exclusion of most or all of the RA decreases the incidence of atrial arrhythmias; therefore, the Fontan procedure evolved by establishing a total cavopulmonary connection (TCPC) by way of either the lateral tunnel (an intra-atrial tunnel) or the extra-cardiac Fontan4,5. Patients who underwent first generation RA-PA Fontan surgery with subsequent development of atrial arrhythmias may benefit from surgical conversion to TCPC with concomitant arrhythmia surgery6,7. Despite significant reduction in arrhythmia burden, a sub-group of patients still develop recurrent arrhythmias8. The extra-cardiac Fontan consists of an IVC to PA conduit and direct connection of the SVC to the PA. Being completely outside the heart, it is thought to have less arrhythmic sequelae9; however, the conduit being made of stiff Gore-Tex, it also precludes access into the heart. This report outlines an approach to catheter ablation in a patient with extra-cardiac Fontan palliation where the heart was accessed via the conduit.

Two-Dimensional and Doppler Echocardiography Reliably Predict Severe Pulmonary Regurgitation as Quantified by Cardiac Magnetic Resonance

BACKGROUND The grading of pulmonary regurgitation (PR) severity by two-dimensional (2D) and Doppler echocardiography is not standardized. Cardiovascular magnetic resonance imaging is the clinical gold standard for PR quantification. The purpose of this study was to determine the best 2D and Doppler echocardiographic predictors of severe PR. METHODS Thirty-six patients with tetralogy of Fallot or pulmonary valve stenosis with prior pulmonary valvuloplasty or transannular or subannular patch repair underwent 2D and Doppler echocardiography and cardiovascular magnetic resonance. Two-dimensional and Doppler echocardiographic measurements used to predict severe PR included diastolic flow reversal in the main or branch pulmonary arteries, PR jet width > or = 50% of the pulmonary annulus, PR pressure half-time < 100 ms, and PR index < 0.77. RESULTS With the exception of PR index, all indices were significant independent predictors of severe PR. The best univariate predictor of severe PR was branch pulmonary artery diastolic flow reversal. CONCLUSION Two-dimensional and Doppler echocardiography reliably identified severe PR in this cohort.

Arrhythmia Recurrence in Adult Patients with Single Ventricle Physiology Following Surgical Fontan Conversion: Arrhythmia Recurrence Following Fontan Conversion

OBJECTIVES To evaluate the incidence of atrial tachy-arrhythmia (AT) recurrence following conversion from right atrial-pulmonary artery (RA-PA) Fontan to total cavopulmonary connection (TCPC) in adults. BACKGROUND AT is a recognized sequel of Fontan palliation, especially in RA-PA Fontans, and is associated with significant morbidity. While catheter ablation achieves fairly reliable short-term success with low morbidity, conversion to TCPC with arrhythmia surgery is a highly effective treatment option for the classical Fontan patients with incessant AT. METHODS Single center retrospective review. RESULTS Twenty-seven adults underwent Fontan conversion from RA-PA to TCPC, mostly for AT indications (n = 24). Nine (33%) underwent conversion to a lateral tunnel (LT) and 18 (67%) to an extracardiac (EC) Fontan. Two patients died <30 days post-operatively. Both had liver failure and had been turned down for cardiac/liver transplantation. In-hospital complications occurred in 15/27 patients (55%), including recurrence of AT requiring cardioversion in six patients (22%) and persistent pleural effusions in 4 (15%). Mean follow-up was 4.2 years (range 3 months-14 years). Functional capacity improved from mean New York Heart Association (NYHA) class 1.8 pre-conversion to 1.2 post-conversion (P= 0.008). Twenty-one patients had concomitant arrhythmia surgery (MAZE in 12 patients with IART and Cox-MAZE in nine patients with A-Fib +/- IART). Of these, 3/21 (14%) had AT recurrence >3 months following conversion. CONCLUSIONS Conversion from RA-PA Fontan to TCPC, with arrhythmia surgery, decreases AT recurrence and improves functional capacity. The risk of peri-operative mortality is highest in patients with cirrhosis. AT recurred in 14% of patients.