Search

Background: QT interval variability (QTV) and heart rate turbulence (HRT) are measures of cardiac autonomic function, which, when abnormal, are correlated with ventricular arrhythmias and worse clinical outcome. This study aims to evaluate QTV and HRT in patients with a systemic right ventricle (RV) and to assess correlations with clinical characteristics., Methods: In a retrospective cohort study, QTV and HRT were derived from 24-h Holter registrations of patients with a systemic RV and healthy controls. QTV and HRT were compared between groups. In patients, the association between QTV, HRT, and clinical characteristics was assessed., Results: Holter recordings from 40 patients (mean age 40 years, 16 females) and 37 healthy controls (mean age 42 years, 21 females) were analyzed. Groups were comparable in terms of age and sex. QTV was increased in patients compared with controls (p < 0.001), HRT did not differ significantly between the groups. Increased QTV and decreased HRT correlated with medication use, especially of diuretics, and with clinical events, particularly supraventricular arrhythmias. Increased QTV correlated with reduced systemic RV function. Decreased HRT was independently associated with a larger number of past clinical events (estimate -0.33, 95% CI -0.63 to -0.02, p = 0.037). QTV was higher in women in both patients and controls (p = 0.041 and p = 0.034, respectively)., Conclusions: QTV and HRT are associated with clinical factors and events in patients with a systemic RV. Further studies are mandatory to confirm their prognostic value., (Copyright © 2020. Published by Elsevier Ltd.)

Background: Patients with a systemic right ventricle are prone to develop heart failure. Abnormal heart rate variability (HRV), a measure of autonomic dysfunction, is associated with morbidity and mortality in patients with left ventricular failure. The association between HRV and supraventricular arrhythmias (SVTs), which are associated with adverse events in this population, was assessed., Methods: 24-Hour Holter recordings of patients with a systemic right ventricle and healthy controls were analysed in a retrospective cohort study. HRV was calculated and compared between groups. Correlation coefficients were determined for HRV variables and clinical characteristics. The relation between HRV and SVTs was investigated with linear regression., Results: The patient group included 29 patients (69%) late after Mustard or Senning correction for transposition of the great arteries, and 13 patients with congenitally corrected transposition of the great arteries (31%). The control group included 38 subjects. HRV was significantly lower in patients compared with controls. In the patient group, lower SDANN (standard deviation of the average NN intervals calculated over 5-minute intervals) was independently associated with a higher number of supraventricular arrhythmias (95% CI -0.03 to -0.0004, p = 0.045). In exploratory correlation analysis, several HRV variables correlated with echocardiographic systemic right ventricular function (rho = 0.36, p = 0.02 for SDANN), and exercise capacity (rho = 0.39, p = 0.05 for SDANN)., Conclusion: In patients with a systemic right ventricle, HRV is lower compared with controls and (SDANN) is independently associated with supraventricular arrhythmias., Competing Interests: Declaration of competing interest None of the authors have conflict of interest to declare., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: An anomalous coronary artery is reported in 2% to 23% of patients with tetralogy of Fallot (TOF). Knowledge of coronary anatomy prior to corrective surgery is vital to avoid damage to vessels crossing the right ventricular outflow tract (RVOT). A meta-analysis on the prevalence of anomalous coronary arteries in TOF is lacking to date. Here, an overview of coronary anomalies in TOF is provided and implications for patient management are discussed., Methods: PubMed, Embase and Web of Science were searched. Analysis was done using Revman 5.3 (Cochrane Community, London). The primary analysis focused on the origin and proximal course of the right and left coronary arteries. In addition, the prevalence of large conus arteries and coronary arteriovenous fistulas (CAVF) was calculated., Results: Twenty-eight studies, encompassing 6956 patients, were included; 6% of TOF patients have an anomalous coronary artery. Hereof, 72% cross the RVOT; the majority of the remaining 28% courses behind the aorta. Six percent of patients have a large conus artery and 4% a CAVF. Other coronary anomalies include a left or right coronary artery from the pulmonary trunk or left or right pulmonary artery, coronary tree hypoplasia and anastomoses between coronary and bronchial arteries., Conclusions: The prevalence of coronary anomalies in TOF is 4-6%. In patients with an anomalous coronary artery, 72% cross the RVOT. The combined risk of encountering an anomalous coronary artery or a large conus artery crossing the RVOT is 10.3%. Coronary anatomy should be defined before surgery and the surgical approach adapted accordingly., Competing Interests: Declaration of competing interest None., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: The arterial switch operation is the current treatment for transposition of the great arteries. Long-term outcome mainly depends on the patency of the transferred coronary arteries. This study assessed the presence of abnormal coronary findings and neoaortic root dilation late after arterial switch operation., Methods: In 30 adult patients after arterial switch operation (22 men, 22 ± 3 years), computed tomography angiography was performed to assess the coronary anatomy and abnormal coronary findings, defined as significant stenosis, interarterial coronary course, and acute angled coronary origins. Neoaortic root dimensions and coronary takeoff height were also assessed., Results: The most common coronary anatomy pattern was found in 24 of 30 patients. Variant anatomy patterns were seen in 6 patients (5 with aberrant circumflex artery, 1 with a single ostium). The prevalence of abnormal coronary findings was higher in patients with variant coronary pattern as compared with patients with common coronary pattern (100% and 29%, respectively; p = 0.003). In particular, an acute angle of the coronary origin was frequently observed. In patients with an acute angle, larger dimensions of the aortic annulus (p = 0.016) and the sinus of Valsalva (p = 0.002) were observed. Moreover, a higher takeoff of the right (p = 0.030) and left (p = 0.002) coronary ostium was noted in patients with acute angles., Conclusions: Abnormal coronary findings were frequently observed in adult patients after arterial switch operation, especially in patients with a variant coronary anatomy pattern. Neoaortic root dilation and a higher coronary takeoff may explain part of the pathophysiology. Long-term follow-up is needed to determine the clinical significance of these findings., (Copyright © 2013 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is a heart muscle disorder characterized pathologically by fatty or fibrofatty replacement and electrical instability of the right ventricular myocardium. Clinical manifestations include structural and functional malformations (fatty infiltration, dilatation, aneurysms) of the right ventricle, ECG abnormalities, and presentation with ventricular tachycardias with left bundle branch block pattern or sudden death. The disease often is familial with an autosomal inheritance. The typical hallmarks of ARVD/C are distributed in the so-called "triangle of dysplasia." The functional and morphologic characteristics are relevant to clinical imaging approaches such as contrast angiography, echocardiography, radionuclide angiography, ultrafast computed tomography, and cardiovascular magnetic resonance imaging. Evident forms of the disease are straightforward to diagnose based on a series of diagnostic criteria proposed by the International Task Force for Cardiomyopathy. However, the diagnosis of early and mild forms of the disease often is difficult. Treatment is directed toward preventing life-threatening ventricular arrhythmias in which radiofrequency ablation and implantable defibrillators play an increasing role. Despite new diagnostic and therapeutic approaches in ARVD/C, uncertainties about the etiology of the disease, the genetic basis, the appropriate diagnosis and therapy, and the clinical course of patients with ARVD/C have resulted in several registries to increase our knowledge of this intriguing disease.

Background: Zones of slow conduction facilitate reentry, the major mechanism of ventricular tachycardia (VT) after myocardial infarction (MI). Identification of these zones during sinus rhythm (SR) is desirable for radiofrequency (RF) catheter ablation of VT. Local conduction velocity may correlate with electrogram duration., Objectives: The purpose of this study was to revise the definition of normal electrogram characteristics and to reevaluate the significance of low-amplitude, long-duration electrograms recorded during SR to select RF catheter ablation sites in patients with VT., Methods: Electroanatomic mapping was performed during SR in 10 control patients with normal left ventricles (LVs) and in 10 patients with stable VT after MI. From the controls, reference values for electrogram amplitude, duration (first peak to last peak distance), and fragmentation (positive deflection) were derived. In patients after MI, areas with signals exceeding these values were annotated and related to successful ablation sites., Results: Ninety-five percent of normal LV electrograms were > or =1.0 mV and < or =28 ms (range 5-39 ms) and all had < or =4 deflections. Based on these results, cutoff values were set at 1 mV, four deflections, and 40 ms. In infarcted hearts, 653 electrograms (44%) were <1.0 mV and of these, 303 were > or =40 ms with >4 deflections and restricted to circumscribed areas. Twenty-seven of 28 targeted VTs remained noninducible after RF catheter ablation within these areas, resulting in 86% sensitivity and 94% specificity for low-amplitude, long-duration electrograms predicting successful ablation sites., Conclusion: Identification of successful RF target areas during SR in patients with VT is feasible with high sensitivity and specificity using a mapping strategy based on voltage and duration criteria.