Atrial arrhythmias in adults after repair of tetralogy of Fallot. Correlations with clinical, exercise, and echocardiographic findings

Pregnancy Outcomes in Women with Arrhythmias following Surgical Repair of Cardiac Defects

OBJECTIVE

 The goal of this study was to investigate whether preexisting cardiac arrhythmias are associated with adverse obstetrical outcomes in women with a history of open cardiac surgery.

STUDY DESIGN

 This was a retrospective cohort study of women with a history of open cardiac surgery who delivered at MedStar Washington Hospital Center (Washington, DC) from January 2007 through December 2018. Women with the isolated percutaneous cardiac surgical repair were excluded. Maternal and neonatal outcomes were compared between patients with preexisting cardiac arrhythmias and patients without preexisting cardiac arrhythmias. Maternal outcomes studied were intensive care unit admission, postpartum blood loss greater than 1,000 mL, congestive heart failure development, preeclampsia with severe features, postpartum readmission, postpartum cardiac events, and postpartum length of stay >5 days. Neonatal outcomes investigated were low birth weight <2,500 g, Apgar's scores <7 at 5 minutes, and neonatal intensive care unit admission. Multivariate logistic regression model was used to calculate the adjusted odds ratio (aOR) and 95% confidence intervals.

RESULTS

 The outcomes for 69 deliveries from 56 women with a history of open cardiac surgery were examined. Thirty-three women (48%) had arrhythmias after cardiac surgery with fourteen (20%) requiring implantable cardioverted defibrillators. Two women (6%) with preexisting arrhythmias after cardiac surgery developed postpartum volume overload requiring readmission (p = 0.06). After controlling for age, gestational age at delivery, and BMI, preeclampsia with severe features (p = 0.02) and low birth weight neonates (p = 0.02, aOR = 2.26 [0.56-9.03]) remained statistically more like to occur in patients with preexisting cardiac arrhythmias than in patients without preexisting arrhythmias.

CONCLUSION

 Women with a history of open cardiac surgery and preexisting cardiac arrhythmias prior to pregnancy are more likely to develop preeclampsia with severe features and have low birth weight neonates compared with women with a history of open cardiac surgery without preexisting cardiac arrhythmias.

KEY POINTS

· Preexisting arrhythmias after cardiac surgery was associated with a risk of preeclampsia.. · Neonates of women with preexisting cardiac arrhythmias are more likely to be low birth weight.. · Forty-seven percent of women with open cardiac surgery developed subsequent arrhythmias..

Utility of Cardiac Magnetic Resonance Imaging in Predicting Atrial Arrhythmias in Repaired Tetralogy of Fallot

Arrhythmias are the leading cause of morbidity and mortality in repaired tetralogy of Fallot (TOF), and over 20% of these patients will develop a sustained atrial arrhythmia during their lifetimes. Cardiac magnetic resonance imaging (cMRI) is frequently performed in TOF, although its ability to identify patients at risk of atrial arrhythmias is uncertain. Adult TOF patients (n = 175) with no history of atrial arrhythmia who underwent cMRI between 2003 and 2020 at a single tertiary care center were identified. Clinical characteristics and imaging findings were evaluated to identify a predilection for atrial arrhythmias using Kaplan-Meier survival analysis and log-rank testing. Multivariable Cox regression was used to determine independent predictors of atrial arrhythmias. Over a median follow-up of 3.6 years, 29 patients (17%) developed atrial arrhythmias. Independent predictors of atrial arrhythmia included age (hazard ratio [HR] 1.06 per 1-year increase, 95% confidence interval [CI] 1.02 to 1.09, p = 0.002), diabetes mellitus (HR 4.26, 95% CI 1.26 to 14.41, p = 0.020), indexed right ventricular end-diastolic volume (RVEDVi), (HR 1.20 per 10-ml/m² increase, 95% CI 1.05 to 1.39, p = 0.010), and moderate or greater tricuspid regurgitation (TR) (HR 6.32, 95% CI 2.15 to 18.60, p = 0.001). Utilizing Kaplan-Meier analysis, patients with at least mild right ventricular dilation (RVEDVi >100 ml/m², p = 0.047) and greater than or equal to moderate TR (p <0.001) were found to be significantly more likely to develop atrial arrhythmias. In conclusion, cMRI can help to identify TOF patients at increased risk for atrial arrhythmia beyond standard clinical and imaging data by better quantifying RVEDVi and degree of TR.

Changes in Cortical Thickness Are Associated With Cognitive Ability in Postoperative School-Aged Children With Tetralogy of Fallot

In children with tetralogy of Fallot (TOF), there is a risk of brain injury even if intracardiac deformities are corrected. This population follow-up study aimed to identify the correlation between cerebral morphology changes and cognition in postoperative school-aged children with TOF. Resting-state functional magnetic resonance imaging (rs-fMRI) and the Wechsler Intelligence Scale for Children–Chinese revised edition (WISC-CR) were used to assess the difference between children with TOF and healthy children (HCs). Multiple linear regression showed that the TOF group had a lower verbal intelligence quotient (VIQ, 95.000 ± 13.433, p = 0.001) than the HC group and that VIQ had significant positive correlations with the cortical thickness of both the left precuneus (p < 0.05) and the right caudal middle frontal gyrus (p < 0.05) after adjustment for preoperative SpO2, preoperative systolic blood pressure (SBP), preoperative diastolic blood pressure (DBP) and time of aortic override (AO). Our results suggested that brain injury induced by TOF would exert lasting effects on cortical and cognitive development at least to school age. This study provides direct evidence of the relationship between cortical thickness and VIQ and of the need for strengthened verbal training in school-aged TOF patients after corrective surgery.

How pulmonary valve regurgitation after tetralogy of fallot repair changes the flow dynamics in the right ventricle: An in vitro study

Tetralogy of Fallot is the most common cyanotic congenital disease, affecting 10% of children with congenital heart disease. The surgical management of patients with Tetralogy of Fallot leads, however, to significant detrimental effects on the right ventricle including pulmonary valve regurgitation. This experiment aimed to simulate different cases of pulmonary valve regurgitation with varying degrees of severity in order to observe the changes in flow structures present in the right ventricle. Planar time-resolved particle image velocimetry measurements have been performed on a custom-made double activation simulator reproducing flow conditions in a model of a right ventricle. Changes in flow characteristics in the right ventricle have been evaluated in terms of velocity fields and profiles, tricuspid inflow jet orientation and viscous energy dissipation. Our results show that pulmonary valve regurgitation significantly alters the flow in the right ventricle mostly by impairing the diastolic inflow through the tricuspid valve and by increasing viscous energy loss. This fundamental work should allow for a better understanding of such changes in the RV flow dynamics. It may also help in developing new strategies allowing for a better follow-up of patients with repaired TOF and for decision-making in terms of pulmonary valve replacement.

Implantable cardiac devices in adult patients with repaired tetralogy of Fallot

OBJECTIVES

Implantable cardiac devices are common in patients with tetralogy of Fallot (ToF) (18.3-21.3%) according to previous reports from large centres. We conducted this study to investigate the prevalence and incidence of cardiac devices in a less selected population of patients with ToF and assess factors other than arrhythmia associated with having a device. Design: 530 adult (≥18 years) patients with repaired ToF were identified in the national registry of congenital heart disease (SWEDCON) and matched with data from the Swedish pacemaker registry. Patients with implantable cardiac devices were compared with patients without devices. Results: Seventy-five patients (14.2%) had a device; 51 (9.6%) had a pacemaker and 24 (4.5%) had an implantable cardioverter defibrillator. The incidence in adult age (≥18 years) was 5.9/1000 patient years. Estimated device free survival was 97.5% at twenty, 87.2% at forty and 63.5% at sixty years of age. Compared with previous studies, the prevalence of devices was lower, especially for ICD. In multivariate logistic regression, cardiovascular medication (odds ratio [OR] 3.5, 95% confidence interval [CI] 1.8-6.8), impaired left ventricular function, (OR 2.6, 95%CI 1.3-5.0) and age (OR 1.02, 95%CI 1.002-1.05) were associated with having a device. Conclusion: The prevalence of devices in our population, representing a multicenter register cohort, was lower than previously reported, especially regarding ICD. This can be due to differences in treatment traditions with regard to ICD in this population, but it may also be that previous studies have reported selected patients with more severe disease.

A Methodology to Assess Subregional Geometric Complexity for Tetralogy of Fallot Patients

During surgical repair of tetralogy of fallot (TOF), pulmonary valve preservation (preservative repair) has demonstrated improved long-term outcomes compared to repairs that incise into the valve annulus (nonpreservative repair). Given the influence of geometry on hemodynamics, the success of preservative repair may be linked to the suitability of the preoperative patient geometry. However, the specific patient anatomies that may be predisposed to successful preservative repair are unknown due to significant interpatient variability in right ventricular outflow tract (RVOT) and pulmonary artery geometries, as well as the limitations in current methods of subregional geometric analysis. As a first step toward understanding the link between geometry and hemodynamics in TOF patients at a subregion level, we characterize the TOF geometry from the right ventricular infundibulum (INF) to the left and right pulmonary arteries. Our process consists of segmentation of magnetic resonance (MR) images and analysis of cross-sectional slices of the geometries along the centerlines. For the INF, main, left, and right pulmonary arteries individually, we quantify geometric parameters important in determining hemodynamic characteristics such as flow separation and recirculation, which can influence the degree of regurgitation. Specifically, we calculate the diameter along the subregion length, the average diameter, length, and tortuosity for each segment, as well as the bifurcation, left pulmonary artery (LPA) and right pulmonary artery (RPA) branch angles. This approach enables direct geometric comparisons within and among patients and allows for observation of the range in anatomic presentation. We have applied this approach to a dataset of 11 postoperative TOF patients, repaired with both preservative and nonpreservative surgical techniques.

Routine Detection of Atrial Fibrillation/Flutter Predicts a Worse Outcome in a Cohort of Tetralogy of Fallot Patients During 23 Years of Follow-Up

Atrial flutter/fibrillation (AFL/AF) is a late complication in adults with repaired tetralogy of Fallot (TOF). Its effects on long-term prognosis are not fully understood. We evaluate the impact of AFL/AF in adults with repaired TOF on global mortality and unplanned hospitalizations during follow-up, and the predictors for AFL/AF occurrence. The presence of AFL/FA was analysed in all exams performed during the last 10 years of outpatients follow up in a unicentric cohort of repaired TOF between 1980 and 2003. Two-hundred and six patients were included; at a mean follow-up of 21 ± 8.2 years, there were 5 deaths (19.2%) in the AFL/AF group and 2 (1.1%) in those without arrhythmia (p < 0.001). Patients with AFL/AF where older at the time of the surgical repair (p < 0.001) and had a higher rate of reinterventions (p = 0.003). No differences were observed between the groups regarding the use of a transannular patch, ventriculotomy and previous palliative shunt. QRS duration was longer in patients with AFL/AF (174 ± 33.4) when compared to those without arrhythmia (147 ± 39.6; p < 0.0001). Age at surgery, QRS duration, and tricuspid regurgitation ≥ moderate were independent risk predictors for AFL/AF. In the multivariate analysis, atrial flutter/fibrillation and QRS duration were predictors of death and hospitalization. AFL/AF is associated with an increased risk of death and hospitalization during the follow-up of patients with repaired TOF. Early detection of AFL/AF and their predictors is an essential step in the evaluation of such population.

Impact of Percutaneous Pulmonary Valve Implantation on the Timing of Reintervention for Right Ventricular Outflow Tract Dysfunction

Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart defect. Early surgical repair has dramatically improved the outcome of this condition. However, despite the success of contemporary approaches with early complete repair, these are far from being curative and late complications are frequent. The most common complication is right ventricle outflow tract (RVOT) dysfunction, affecting most patients in the form of pulmonary regurgitation, pulmonary stenosis, or both, and can lead to development of symptoms of exercise intolerance, arrhythmias, and sudden cardiac death. Optimal timing of restoration of RVOT functionality in asymptomatic patients with RVOT dysfunction after TOF repair is still a matter of debate. Percutaneous pulmonary valve implantation, introduced almost 2 decades ago, has become a major game-changer in the treatment of RVOT dysfunction. In this article we review the pathophysiology, the current indications, and treatment options for RVOT dysfunction in patients after TOF repair with a focus on the role of percutaneous pulmonary valve implantation in the therapeutic approach to these patients.

Transient Notch Activation Induces Long-Term Gene Expression Changes Leading to Sick Sinus Syndrome in Mice

RATIONALE

Notch signaling programs cardiac conduction during development, and in the adult ventricle, injury-induced Notch reactivation initiates global transcriptional and epigenetic changes.

OBJECTIVE

To determine whether Notch reactivation may stably alter atrial ion channel gene expression and arrhythmia inducibility.

METHODS AND RESULTS

To model an injury response and determine the effects of Notch signaling on atrial electrophysiology, we transiently activate Notch signaling within adult myocardium using a doxycycline-inducible genetic system (inducible Notch intracellular domain [iNICD]). Significant heart rate slowing and frequent sinus pauses are observed in iNICD mice when compared with controls. iNICD mice have structurally normal atria and preserved sinus node architecture, but expression of key transcriptional regulators of sinus node and atrial conduction, including Nkx2-5 (NK2 homeobox 5), Tbx3, and Tbx5 are dysregulated. To determine whether the induced electrical changes are stable, we transiently activated Notch followed by a prolonged washout period and observed that, in addition to decreased heart rate, atrial conduction velocity is persistently slower than control. Consistent with conduction slowing, genes encoding molecular determinants of atrial conduction velocity, including Scn5a (Nav1.5) and Gja5 (connexin 40), are persistently downregulated long after a transient Notch pulse. Consistent with the reduction in Scn5a transcript, Notch induces global changes in the atrial action potential, including a reduced dV_m/dt_max. In addition, programmed electrical stimulation near the murine pulmonary vein demonstrates increased susceptibility to atrial arrhythmias in mice where Notch has been transiently activated. Taken together, these results suggest that transient Notch activation persistently alters ion channel gene expression and atrial electrophysiology and predisposes to an arrhythmogenic substrate.

CONCLUSIONS

Our data provide evidence that Notch signaling regulates transcription factor and ion channel gene expression within adult atrial myocardium. Notch reactivation induces electrical changes, resulting in sinus bradycardia, sinus pauses, and a susceptibility to atrial arrhythmias, which contribute to a phenotype resembling sick sinus syndrome.

Left Atrial Deformation Analysis in Patients with Corrected Tetralogy of Fallot by 3D Speckle-Tracking Echocardiography (from the MAGYAR-Path Study)

Background

Three-dimensional (3D) echocardiography coupled with speckle-tracking echocardiographic (STE) capability is a novel methodology which has been demontrated to be useful for the assessment of left atrial (LA) volumes and functional properties. There is increased scientific interest on myocardial deformation analysis in adult patients with corrected tetralogy of Fallot (cTOF).

Objectives

To compare LA volumes, volume-based functional properties and strain parameters between cTOF patients and age- and gender-matched healthy controls.

Methods

The study population consisted of 19 consecutive adult patients with cTOF in sinus rhythm nursing at the University of Szeged, Hungary (mean age: 37.9 ± 11.3 years, 8 men, who had repair at the age of 4.1 ± 2.5 years). They all had undergone standard transthoracic two-dimensional Doppler echocardiographic study extended with 3DSTE. Their results were compared to 23 age- and gender-matched healthy controls (mean age: 39.2 ± 10.6 years, 14 men).

Results

Increased LA volumes and reduced LA emptying fractions respecting cardiac cycle could be demonstrated in cTOF patients compared to controls. LA stroke volumes featuring all LA functions showed no differences between the 2 groups examined. LA global and mean segmental uni- and multidirectional peak strains featuring LA reservoir function were found to be diminished in adult patients with cTOF as compared to controls. Similarly to peak strains reduced global and mean segmental LA strains at atrial contraction characterizing atrial booster pump function could be demonstrated in cTOF patients as compared to controls.

Conclusions

Significant deterioration of all LA functions could be demonstrated in adult patients with cTOF late after repair.

Radiofrequency ablation of atrial tachyarrhythmias in adults with tetralogy of Fallot - predictors of success and outcome

BACKGROUND

Adults with tetralogy of Fallot experience atrial tachyarrhythmias; however, there are a few data on the outcomes of radiofrequency ablation. We examined the characteristics, outcome, and predictors of recurrence of atrial tachyarrhythmias after radiofrequency ablation in tetralogy of Fallot patients. Methods/results Retrospective data were collected from 2004 to 2013. In total, 56 ablations were performed on 37 patients. We identified two matched controls per case: patients with tetralogy of Fallot but no radiofrequency ablation and not known to have atrial tachyarrhythmias. Acute success was 98%. Left atrial arrhythmias increased in frequency over time. The mean follow-up was 41 months; 78% were arrhythmia-free. Number of cardiac surgeries, age, and presence of atrial fibrillation were predictors of recurrence. Lone cavo-tricuspid isthmus-dependent flutter reduced the likelihood of atrial fibrillation. Right and left atria in patients with tetralogy of Fallot were larger in ablated cases than controls. NYHA class was worse in cases and improved after ablation; baseline status predicted death. Of matched non-ablated controls, a number of them had atrial fibrillation. These patients were excluded from the case-control study but analysed separately. Most of them had died during follow-up, whereas of the matched ablated cases all were alive and the majority in sinus rhythm.

CONCLUSION

Patients with tetralogy of Fallot and atrial tachyarrhythmias have more dilated atria than those without atrial tachyarrhythmias. Radiofrequency ablation improves functional status. Left atrial ablation is more commonly required with repeat procedures. There is a high prevalence of atrial tachyarrhythmias, particularly atrial fibrillation, in patients with tetralogy of Fallot; early radiofrequency ablation may have a protective effect against this.

Adults with repaired tetralogy: low mortality but high morbidity up to middle age

Objective

Survival of patients with repaired tetralogy of Fallot (rToF) into young adulthood is very good. Concerns exist, however, over long-term morbidity and mortality as these subjects reach middle age. We aimed to assess survival and the prevalence of complications in patients with rToF seen in our Adult Congenital Heart Disease (ACHD) service.

Methods

One hundred and sixty-eight consecutive patients with ‘simple rToF’, aged over 16 years, followed up at our tertiary-level ACHD service in Sydney, Australia since 2000, were included. We documented mortality and analysed the prospectively defined composite end points of (a) ‘Serious adverse events’, including death, heart failure hospitalisation and/or documented ventricular arrhythmia and (b) ‘Adverse events’ inclusive of the above and endocarditis, atrial arrhythmia, defibrillator and/or pacemaker implantation.

Results

Mean age at the last follow-up was 34±12 years, and 55% were men. There were 10 (6%) deaths, and 26 patients (16%) experienced a ‘serious adverse event’. Fifty-one patients (30%) experienced an ‘adverse event’ and 29 patients had atrial arrhythmias. One hundred and one (61%) patients had at least one pulmonary valve replacement. By age 40 years, 93% were free of serious adverse events, and 83% were free of any adverse event. By age 50 years, only 56% had not had an adverse event. Older age and history of atrial arrhythmia were predictive of serious adverse events.

Conclusion

Survival into mid-adulthood in patients with rToF is very good; however, a substantial number of survivors have adverse events by the age of 50 years.

Anesthetic Considerations for Adult Cardiac Surgery Patients with Congenital Heart Disease

The number of adults with congenital heart disease surviving into adulthood is increasing. The proportion of adults undergoing revision of a previous repair is increasing in comparison to those that present for a palliative or curative operation. At the Toronto Congenital Cardiac Centre for Adults, 528 patients underwent cardiac surgery between January 1, 1992 and December 31, 2001. The anesthetic management of the surgical correction of simple and complex congenital heart lesions includes general physiologic considerations such as dysrhythmias, hypoxemia, polycythemia, and pulmonary hypertension. Palliative shunts from early childhood have anatomical and physiologic implications for the adult. Preparation for the operating room and postoperative care are natural extensions of the anesthetic management of the surgical correction of the congenital heart lesions. Anesthetic management of septal lesions in the interventional suite and operating room is discussed. Complex lesions such as tetralogy of Fallot, transposition of the great arteries, Glenn anastomosis, and the Fontan operation are reviewed. The anesthetic management of these patients is rewarding but impossible without an integrated team approach involving cardiologists, surgeons, perfusionists, and nursing staff.

[Arrhythmia in adults with congenital heart defects : Incidence, substrates, and mechanisms]

Arrhythmia management is one of the main challenges in the treatment of adult patients with congenital heart disease (ACHD). Apart from heart failure, arrhythmias are mainly responsible for morbidity and mortality in these patients. Supraventricular tachycardia is more frequent than ventricular arrhythmias and is not only associated with debilitating symptoms, but is often as threatening as ventricular tachycardia. The incidence depends on the underlying defect, type, and time of repair. For the overall ACHD population the incidence of supraventricular tachycardia is up to 50 % and increases with age and time since surgery. Arrhythmia substrate relates to structural abnormalities due to the congenital defect and most importantly to the amount of incisions and material used for repair. In addition, poor hemodynamic conditions influence substrate through dilatation, hypertrophy, and fibrosis. Both supraventricular and ventricular arrhythmias are due to a macroreentrant mechanism in the vast majority of patients, but focal arrhythmias occasionally occur as well.

Sleep-Disordered Breathing in Patients with Pulmonary Valve Incompetence Complicating Congenital Heart Disease

OBJECTIVE

Long standing pulmonary regurgitation results in deleterious effects on right heart size and function with late consequences of right heart volume overload including ventricular dilatation, propensity to arrhythmia and right heart failure. As sleep disordered breathing may predispose to elevations in pulmonary vascular resistance and associated negative effects on right ventricular function, we sought to assess this in patients with underlying congenital heart disease.

DESIGN

We performed a pilot study to evaluate the incidence of sleep-disordered breathing in a patient population with a history of long standing pulmonary valve incompetence in patients with congenital heart disease using overnight oximetry.

PATIENTS

Patients with a background of tetralogy of Fallot repair or residual pulmonary incompetence following previous pulmonary valve intervention for congenital pulmonary stenosis were included.

RESULTS

Twenty-two patients underwent overnight oximetry. The mean age of the cohort was 34.3 ± 15.2 years with no patients observed to have severe underlying pulmonary hypertension. Abnormal overnight oximetry was seen in 13/22 patients (59.1%) with 2/22 (9.1%) patients considered to have severe abnormalities.

CONCLUSIONS

An important proportion of patients with a background of pulmonary incompetence complicating congenital heart disease are prone to the development of sleep-disordered breathing as assessed by overnight oximetry. Further study into the prevalence and mechanisms of sleep-disordered breathing in a larger cohort are warranted.

Longitudinal development of psychopathology and subjective health status in CHD adults: a 30- to 43-year follow-up in a unique cohort

OBJECTIVE

To determine longitudinal changes in psychopathology in a cohort of patients 30-43 years after their first cardiac surgery for Congenital Heart Disease (CHD) in childhood, to compare outcomes of the 30- to 43-year follow-up with normative data, and to identify medical predictors for psychopathology.

METHODS

This study is the third follow-up of this cohort. The first and second follow-ups of this same cohort were conducted in 1990 and 2001, respectively. At all three follow-ups, psychopathology was assessed with standardised, parallel questionnaires. In 2011, subjective health status was assessed by the Short Form-36. Medical predictor variables were derived from medical examinations and medical records.

RESULTS

In this third follow-up, a total of 252 patients participated. Of these, 152 patients participated in all three follow-ups. Over a 30-year period, proportions of patients showing psychopathology decreased significantly. At the 30- to 43-year follow-up, overall outcomes on psychopathology for the CHD sample were similar or even better compared with normative groups. Subjective health status was also better compared with normative data. No differences were found between cardiac diagnostic groups. Medical variables that predicted the course of psychopathology over time were as follows: the scar, as judged by the patient, results of the first cardiac surgery, and the number of hospitalisations.

CONCLUSIONS

Over a 30-year period, psychopathology decreased in patients with CHD. Levels of psychopathology in these patients, who are now aged between 30 and 54 years, were comparable or even better than normative data.

Atrial macroreentry in congenital heart disease

Macroreentrant atrial tachycardia is a common complication following surgery for congenital heart disease (CHD), and is often highly symptomatic with potentially significant hamodynamic consequences. Medical management is often unsuccessful, requiring the use of invasive procedures. Cavotricuspid isthmus dependent flutter is the most common circuit but atypical circuits also exist, involving sites of surgical intervention or areas of scar related to abnormal hemodynamics. Ablation can be technically challenging, due to complex anatomy, and difficulty with catheter stability. A thorough assessment of the pa-tients status and pre-catheter ablation planning is critical to successfully managing these patients.

[Prevention and treatment of cardiac arrhythmia in patients with congenital heart defects: surgical aspects]

Catheter ablation procedures have become established over the years due to their effectiveness and low invasiveness and have changed the indications for surgical treatment. The main field of activity of cardiac surgery remains the treatment of patients with congenital heart defects which show arrhythmia and necessitate surgical treatment. The combination of surgical ablative measures with a good view of the site using modern ablation instruments, atrial reduction by tissue resection and correction of the defect with the resulting volume relief, bring the best conditions for a curative treatment of arrhythmia. The same applies to the treatment of ventricular tachycardia resulting from old scars and residual defects. Special attention should be given to patients who received a Fontan conversion. This operation is a unique opportunity to relieve volume which in turn reduces the atrial size and at the same time to take ablative measures to restore sinus rhythm. The results are promising with low mortality and morbidity, high efficiency and finally a clear improvement of the functional status of patients. In appropriate cases minimally invasive surgical procedures can help where pharmacological and catheter ablation therapies remain ineffective.

Atrial mechanics after surgical repair of tetralogy of Fallot

BACKGROUND

Ventricular diastolic dysfunction in patients with repaired tetralogy of Fallot (TOF) may affect atrial mechanics. This study aimed to explore right atrial (RA) and left atrial (LA) mechanics in repaired TOF patients and their relationship with ventricular diastolic function.

METHODS

Fifty-four patients (36 males), aged 17.8 ± 8.3 years, who had undergone TOF repair at 3.9 ± 3.3 years and 40 healthy subjects aged 16.9 ± 6.3 years (P = 0.57) were studied. Right and LA peak positive, peak negative, and total strain, strain rate at ventricular systole (SRs ), early diastole (SRed ), and atrial contraction (SRac ), and electromechanical delay were determined using speckle tracking echocardiography (STE). Ventricular diastolic function was assessed by tissue Doppler imaging and STE. Ventricular volumes and pulmonary regurgitant volume were derived from 3D echocardiography.

RESULTS

Compared with controls, patients had significantly lower RA and LA peak positive and total strain, SRs , SRed , and SRac (all P < 0.001). The timing of RA (178 ± 33 msec vs. 152 ± 17 msec, P < 0.001) and LA (170 ± 32 msec vs. 152 ± 24 msec, P = 0.006) electromechanical coupling (EMC) was significantly longer in patients than in controls. The RA total strain, SRs , SRed , SRac , and EMC correlated positively with corresponding LA parameters (all P < 0.001). The RA and LA total strain and SRed were associated positively with diastolic annular velocities and strain rates of respective ventricles (all P < 0.05). The LA SRed correlated negatively with pulmonary regurgitant volume (r = -0.33, P = 0.016) and RV end-diastolic volume (r = -0.33, P = 0.015).

CONCLUSION

Mechanics of both atria are impaired in patients after repair of TOF and are associated with diastolic performance of the respective ventricles.

Chronic pulmonary valve insufficiency after repaired Tetralogy of Fallot: diagnostics, reoperations and reconstruction possibilities

Complete correction of Tetralogy of Fallot, the most common cyanotic congenital heart defect, has now become routine. However, late residual lesions, primarily chronic pulmonary valve insufficiency, may have a negative impact on right-ventricular function, leading to the need for reoperation to insert a competent valve at the right-ventricular outflow. The diagnostic modalities pertaining to the failing right ventricle, the timing for eventual reintervention and the various surgical reconstruction possibilities of the right-ventricular outflow tract are still controversial and evolving, and are reviewed with a brief overview on current trends and future outlooks.

Management of arrhythmias in patients with a tetralogy of Fallot

Although arrhythmias are commonly found in patients with all different types of congenital heart disease, perhaps no patient is at higher risk of late development of arrhythmias that may result in sudden death than in the patient following tetralogy of Fallot repair. Despite major improvement in the surgical repair of this disease, a significant percentage of these patients continue to remain at risk for the late development of arrhythmias, and a small percentage will develop life-threatening arrhythmias and sudden death. Which patients remain at highest risk is still not clearly delineated. Diligent arrhythmia surveillance and aggressive treatment strategies are necessary to minimise this risk. This article highlights important strategies to manage arrhythmia development and prevention in this patient population.