Tricuspid atresia with transposition of the great arteries in adolescents and adults: current state and late complications

Late Arrhythmias Following Fontan Surgery

The incidence of atrial arrhythmias following Fontan repairs varies by the type of surgery and duration of follow-up. The incidence of late atrial tachycardia has been reduced from 60% to less than 20% by surgical modifications. Late ventricular tachycardia is reported in 3% to 12% of patients. Aggressive efforts to eliminate tachycardia and improve hemodynamics may improve clinical status.

Serum markers of systemic right ventricular function and exercise performance

The right ventricle, which faces systemic pressure due to congenital heart disease, often develops premature systolic dysfunction. Cardiac hormones might be useful to identify patients with such systolic dysfunction. This prospective study investigated the relationship of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) levels with right ventricular ejection fraction (RVEF) and exercise performance in patients with a systemic right ventricle. ANP levels were obtained in 24 patients and BNP levels were obtained in 22 patients with systemic right ventricle. Patients underwent exercise study (n = 22) and cardiovascular magnetic resonance imaging (n = 11) or equilibrium radionuclide angiography (n = 13) to determine RVEF. There were 17 patients with complete transposition and 7 patients with corrected transposition. ANP showed an inverse correlation with RVEF (r2 = 0.63, p < 0.001), a weak but statistically significant inverse correlation with exercise duration (r2 = 0.18, p = 0.047) and no relationship with maximal oxygen consumption (peak V'O2) (r2 = 0.10, p = NS). BNP did not show a relationship with any of the parameters measured. ANP shows a strong inverse correlation with RVEF and a weak correlation with exercise duration in patients with a systemic right ventricle. BNP does not show a significant relationship when compared with either parameter. ANP might be a useful tool for identification of systolic right ventricular dysfunction.

Arrhythmia management in the Fontan patient

With longer duration of follow-up, as many as 50% of Fontan patients will develop atrial tachycardia, usually in association with significant hemodynamic abnormalities. Arrhythmia management in the Fontan patient is reviewed. The incidence and type of arrhythmia occurrence are examined, including macro-reentrant rhythm which involves the right atrium, reentrant rhythm localized to the pulmonary venous atrium (seen in patients with lateral tunnel procedures), and atrial fibrillation. Risk factors for development of these arrhythmias are considered, and short- and long-term therapeutic options for medical and surgical treatment are discussed. Surgical results are presented for 117 patients undergoing Fontan conversion and arrhythmia surgery (isthmus ablation (9), modified right atrial maze (38) or Cox-maze III (70)). Operative mortality is low (1/117, 0.8%). Seven late deaths occurred, and include two patients who died shortly following cardiac transplantation (2/6, 33%) after Fontan conversion and arrhythmia surgery. Overall arrhythmia recurrence is 12.8% during a mean follow-up of 56 months. Fontan conversion with arrhythmia surgery can be performed with low operative mortality, low risk of recurrent tachycardia, and marked improvement in functional status in most patients. Because the development of tachycardia is usually an electromechanical problem, attention to only the arrhythmia with medications or ablation may allow progression of hemodynamic abnormalities to either a life-threatening outcome or a point at which transplantation is the only potential option. Because cardiac transplantation in Fontan patients is associated with high early mortality, earlier consideration for surgical intervention is warranted.

Risk of Surgery for Congenital Heart Disease in the Adult: A Multicentered European Study

BACKGROUND

Surgery for congenital heart disease (CHD) has changed considerably during the last three decades. The results of primary repair have steadily improved, to allow treating almost all patients within the pediatric age; nonetheless an increasing population of adult patients requires surgical treatment. The objective of this study is to present the early surgical results of patients who require surgery for CHD in the adult population within a multicentered European study population.

METHODS

Data relative to the hospital course of 2,012 adult patients (age > or = 18 years) who required surgical treatment for CHD from January 1, 1997 through December 31, 2004 were reviewed. Nineteen cardiothoracic centers from 13 European countries contributed to the data collection.

RESULTS

Mean age at surgery was 34.4 +/- 14.53 years. Most of the operations were corrective procedures (1,509 patients, 75%), followed by reoperations (464 patients, 23.1%) and palliative procedures (39 patients, 1.9%). Six hundred forty-nine patients (32.2%) required surgical closure of an isolated ostium secundum atrial septal defect. Overall hospital mortality was 2%. Preoperative cyanosis, arrhythmias, and NYHA class III-IV, proved significant risk factors for hospital mortality. Follow-up data were available in 1,342 of 1,972 patients (68%) who were discharged home. Late deaths occurred in 6 patients (0.5%). Overall survival probability was 97% at 60 months, which is higher for corrective procedures (98.2%) if compared with reoperations (94.1%) and palliations (86.1%).

CONCLUSIONS

Surgical treatment of CHD in adult patients, in specialized cardiac units, proved quite safe, beneficial, and low-risk.

Heart failure therapy in children

The most common reason for heart failure in children is volume overload secondary to a left-to-right shunt. Therefore, an accurate diagnosis with identification of possible surgical or interventional reactions should be the first priority. Medical therapy is mainly based on diuretics, angiotensin-converting enzyme inhibitors, cardiac glycosides and beta-blockers. There are few prospective trials in pediatric cardiology, but the available data reach a similar conclusion to that of adults with heart failure. Diuretics are an important tool in patients with fluid retention, and angiotensin-converting enzyme inhibitors are helpful in patients with volume overload of the ventricles. Cardiac glycosides are still in use, but there is a trend toward primary use of diuretics. Angiotensin-converting enzyme inhibitors and beta-blockers have been used successfully in the treatment of heart failure in children, but there are limited data on its efficacy.

Designing therapeutic strategies for patients with a dominant left ventricle, discordant ventriculo-arterial connections, and unobstructed flow of blood to the lungs

The palliation of the cyanotic child with a dominant morphologically left ventricle, discordant ventriculo-arterial connections, and obstruction to the pulmonary outflow tract has continued to evolve and mature. The evolution began in the early days of surgical palliation with the Blalock-Taussig shunt, extended to construction of cavopulmonary shunts, if required, and then to the Fontan procedure and its subsequent modifications. This journey took nearly 30 years to complete. There is increasing clinical data to document the beneficial effects of this approach, with ever-improving outcomes. Some aspects of the history of the cavopulmonary shunt have been previously reviewed in this journal and elsewhere, as have analysis of outcomes for some groups of patients considered for surgical completion of the Fontan circulation. While there has been some ongoing interest in ventricular septation since the early success of Sakakibara et al., this approach has largely been abandoned. Considerably more challenges and debate resonate in the surgical algorithms defined for patients whose hearts are characterized by a dominant left ventricle, discordant ventriculo-arterial connections, and unobstructed flow of blood to the lungs. This latter group will be the focus of this review, as will the aetiology of the myocardial hypertrophy that is particularly frequent in this group of patients, its clinical recognition, indeed its anticipation, and the multiple surgical strategies designed to prevent or treat it. All these manoeuvres are considered to optimise suitability for, and outcome from, creation of the Fontan circulation.

Surgical outcome for congenital heart malformations in the adult age: a multicentric european study

Congenital heart diseases are currently treated in the pediatric age. However, a conspicuous number of patients requires treatment in the adult age. This study has been undertaken by members of the European Congenital Heart Surgeons Association with the aim of evaluating the impact of cardiac surgery in this particular age group. We have collected data from 1,247 patients who underwent 1,287 operations during a 5-year period between January 1, 1997 and December 31, 2001. Patients were divided into three groups: (1) palliative procedures (4.4%), operation performed to improve patients' clinical status without restoring normal anatomy or physiology; (2) repair (79.3%), operation performed to achieve an anatomic or physiologic repair with separation of the pulmonary from the systemic circulation (included in this group are also Fontan-type repair and one and a half ventricle repair); (3) reoperation (16.3%), all the reoperations performed after repair (either anatomic or physiologic). Hospital mortality (within 30 days) was 2.4% (range, 0% to 15.3% in different centers). Kaplan-Meier estimates shows a 94% survival at 4 years, which is higher for repair (95%) as compared with reoperations (92%) or palliations (88%). Surgery for congenital heart disease in the adult age is a safe, beneficial, and low-risk treatment that modifies patients' natural history by improving their clinical status.

The Fontan procedure in adults

BACKGROUND

A retrospective clinical study was performed to document the course of adult patients undergoing the Fontan procedure.

METHODS

Between 1982 and 1994, 21 adults aged 18 to 40 years (mean age, 27 +/- 7 years) underwent a Fontan procedure. Anatomic diagnosis was tricuspid atresia in 9, double-inlet left ventricle in 4, and various single ventricles in 8. Four underwent a right atria-right ventricle connection, 13 had a right atria-pulmonary artery connection, and 4 had a lateral-tunnel Fontan. Three of these 4 had a snare-adjustable atrial septal defect. Preoperative risk factors assessed were left ventricular end-diastolic pressure greater than 10 mm Hg, ejection fraction lower than 0.45, mean pulmonary artery pressure higher than 15 mm Hg, transpulmonary gradient greater than 10 mm Hg, pulmonary artery abnormalities, and atrioventricular valve regurgitation. Mean preoperative risk score was 1.6 /-1.1. Mean New York Heart Association class was 2.6 +/- 0.5.

RESULTS

The operative mortality rate was 5% (1/21). Six patients (30%) had a major complication, four being prolonged effusions. One patient was lost to follow-up; the remaining 20 have been followed for a mean of 7.4 +/- 3.8 years. At follow-up, mean New York Heart Association class was 1.7 +/- 0.5. There has been one late death (5%) at 9 2/3 years, which was probably due to ventricular arrhythmia. Three patients (16%) have required and survived reoperation. During follow-up, 7 patients (37%) have had development of atrial arrhythmias requiring medication, and 2 have been treated for ventricular arrhythmias.

CONCLUSIONS

These results indicate that properly selected adults can undergo the Fontan procedure with low morbidity and mortality. However, late-developing arrhythmias, need for reoperation, and decreasing ventricular function are serious problems that mandate careful follow-up.

Electrophysiologic findings after Fontan repair of functional single ventricle

Cardiac arrhythmias are well recognized sequelae of the Fontan operation for complex congenital anomalies. In this study the electrophysiologic effects of the Fontan procedure were evaluated in 30 patients who underwent cardiac catheterization with electrophysiologic study 1.9 +/- 1.3 years (mean +/- SD) after modified Fontan repair for functional single ventricle. Abnormalities of sinus node or ectopic pacemaker automaticity were detected in 50% (15 patients) by determination of a prolonged corrected sinus node or pacemaker recovery time. Total sinoatrial conduction time was prolonged in 50% of the patients with normal sinus rhythm. Sinus node or ectopic atrial pacemaker function was entirely normal in only 43% of patients. The predominant atrial rhythm was normal sinus in 70% and ectopic atrial or junctional in 30%. Abnormalities of atrial effective and functional refractory periods were noted in 43% of patients and were most pronounced at faster paced cycle lengths. Atrial endocardial catheter mapping revealed intraatrial conduction delays between adjacent sites in 76% of the patients tested and in eight of nine patients with inducible intraatrial reentry. Programmed atrial stimulation induced nonsustained supraventricular arrhythmias in 10% of the 30 patients and sustained arrhythmias in 27%. Intraatrial reentry was the most common inducible arrhythmia and was present in seven of the eight patients with sustained and two of the three patients with nonsustained atrial arrhythmias. Atrioventricular conduction abnormalities were noted in 10% (three patients). No patient had inducible ventricular arrhythmias with programmed ventricular stimulation. The electrophysiologic findings after Fontan repair include abnormal sinus node function, prolonged atrial refractoriness, delayed intraatrial conduction and inducible atrial arrhythmias.(ABSTRACT TRUNCATED AT 250 WORDS)