Burden and Impact of Arrhythmias in Repaired Tetralogy of Fallot

Concurrent Acute Limb Ischemia and Pulmonary Embolism in an Adult With Repaired Tetralogy of Fallot: A Case Report

Simultaneous acute limb ischemia (ALI) and pulmonary embolism (PE) are extremely rare, with the current literature providing a limited understanding of shared mechanisms. We report a rare case of concurrent ALI and PE presentation in a patient with a history of repaired tetralogy of Fallot (TOF), emphasizing the possible association between congenital heart disease and thromboembolic risk, potentially through residual hemodynamic abnormalities or arrhythmias. The case involves a 48-year-old male with a history of TOF repair in childhood who developed simultaneous ALI and PE approximately 48 years after the surgical repair. The patient presented with sudden right lower extremity pain and swelling; was classified as Rutherford IIa ALI; and underwent urgent endovascular revascularization that included an overnight tissue plasminogen activator infusion and a relook angiogram the next day. During admission, the common embolic etiologies of his presentation were excluded by multiple investigations, including transthoracic echocardiography, thrombophilia panel, and occult malignancy screens. Although the patient had multiple cardiovascular risk factors, including obesity, smoking, and hypertension, it is most likely the history of TOF repair that contributed the most to the concurrent thromboembolic presentation, especially given that TOF repair has been reported to be associated with chronic complications in adult patients, such as persistent right ventricular dysfunction and arrhythmias. A multidisciplinary team of interventional cardiologists, pulmonologists, and hematologists managed the case, reflecting the difficulty of managing concomitant thromboembolic events and monitoring and evaluating thromboembolic risk factors for treated congenital heart disease, most specifically TOF, in adult patients.

Trends in Tetralogy of Fallot-Related Mortality in the United States Between 1999 and 2020

We sought to identify mortality trends related to Tetralogy of Fallot (ToF) in the U.S. population, with specific emphasis on age-related, racial, and geographic differences. Death certificate data was retrieved from the CDC WONDER database, where crude mortality rate (CMR) and age-adjusted mortality rates (AAMR) with 95% CIs per 1,000,000 population were identified, along with annual percentage changes (APCs) and average annual percentage change (AAPC) determined by Joinpoint regression. From 1999 to 2020, a total of 5523 deaths were reported in association with ToF, with nearly half of all deaths occurring during the first year of life. The AAMR steadily decreased from 1999 to 2020 (AAPC: - 1.26, 95% CI - 2.29 to -0.38, p-value = 0.012). Males had a slightly higher AAMR (0.91) than females (0.77). Non-Hispanic (NH) Blacks/African Americans had a higher AAMR (1.00) compared with NH Whites (0.83). Infants less than a year old exhibited the highest CMRs among all age groups. Although lower rates were seen among all age strata < 45 years of age, deaths in patients > 45 years significantly increased from 2013 to 2020 (APC 6.17, 95% CI 0.79 to 20.35, p-value = 0.047). Rural areas consistently exhibited greater AAMRs and lesser declines over time compared to urban areas, with most deaths occurring in medical facilities. Over the last 2 decades in the US, the mortality rates associated with ToF have steadily decreased. Focusing resources on these higher risk populations may prove beneficial.

Predictors of Atrial Arrhythmia in Adults with Repaired Tetralogy of Fallot

Tetralogy of Fallot (TOF), the most common cyanotic congenital heart disease in adults, has excellent long-term survival. However, many patients (30-45%) develop late arrhythmias. Previous studies have identified predictors of arrhythmia (atrial or ventricular) using clinical markers that predate arrhythmia onset by many years. Our objective was to develop a predictive model for incident atrial arrhythmias within two years of clinical evaluation and diagnostic testing. A single-center nested unmatched case-control study of 174 adults with repaired TOF. We included only patients with results from ECG and echocardiogram data in the required time interval (3-24 months before first arrhythmia for cases; 24 months of follow-up for controls). A predictive multivariable model for risk of incident atrial arrhythmia was developed using logistic regression with a least absolute shrinkage and selection operator (LASSO). Of 41 demographic, surgical, and diagnostic variables, six were selected as having predictive value for atrial arrhythmia based on cross validation. The factors with the greatest predictive value in decreasing order were moderate / severe tricuspid regurgitation (adjusted odds ratio (OR) 149.42), QRS fragmentation (OR 28.08), severe pulmonary regurgitation (OR 8.22), RV systolic dysfunction (OR 2.95), 1st degree AV block (OR 2.59), and age at time of surgical repair (OR 1.02). Predictors for atrial arrhythmia in our study suggested abnormal right ventricle anatomical function and electrophysiologic properties (conduction and repolarization) as the primary underlying substrate.

Navigating the path of TOF- A Literature review unveiling maternal-fetal dynamics, treatment strategies and psychological dimensions

Tetralogy of Fallot (TOF) is a complex congenital heart defect that poses unique challenges for both mothers and their unborn children. This comprehensive review, aims to provide a holistic exploration of the maternal-fetal dynamics, treatment strategies, and psychological dimensions involved in navigating the path of TOF during pregnancy. It delves into the physiological changes that occur during pregnancy in TOF patients, including pulmonary regurgitation, right ventricular hypertrophy, and the overriding aorta. By understanding these dynamics, healthcare professionals can tailor treatment strategies to optimize maternal and fetal outcomes. The review further investigates the treatment strategies employed in managing TOF during pregnancy, encompassing medical interventions, cardiac monitoring, and multidisciplinary care. It explores the role of advanced imaging techniques, such as echocardiography and cardiac magnetic resonance imaging, in assessing TOF severity and guiding treatment decisions. The psychological factors influencing maternal adaptation, coping strategies, and the long-term implications on the child's psychological development are also examined. The integration of multidisciplinary approaches, including cardiac care, psychosocial support, and mental health interventions, can orchestrate a harmonious symphony of maternal-fetal well-being in the challenging journey of TOF pregnancies. Future research endeavours should continue to explore these dimensions, further refining treatment strategies and enhancing the understanding of TOF pregnancies for improved outcomes.

Genetic insights into non-syndromic Tetralogy of Fallot

Congenital heart defects (CHD) include structural abnormalities of the heart or/and great vessels that are present at birth. CHD affects around 1% of all newborns worldwide. Tetralogy of Fallot (TOF) is the most prevalent cyanotic congenital cardiac abnormality, affecting three out of every 10,000 live infants with a prevalence rate of 5-10% of all congenital cardiac defects. The four hallmark characteristics of TOF are: right ventricular hypertrophy, pulmonary stenosis, ventricular septal defect, and overriding aorta. Approximately 20% of cases of TOF are associated with a known disease or chromosomal abnormality, with the remaining 80% of TOF cases being non-syndromic, with no known aetiology. Relatively few TOF patients have been studied, and little is known about critical causative genes for non-syndromic TOF. However, rare genetic variants have been identified as significant risk factors for CHD, and are likely to cause some cases of TOF. Therefore, this review aims to provide an update on well-characterized genes and the most recent variants identified for non-syndromic TOF.