Abstract Anatomy and pattern of electrical activation predict the function and contraction pattern of the heart. Patients with primum atrioventricular septal defect (primum AVSD) present with ...abnormality of both anatomical arrangements and electric activation and serve therefore as an interesting population for studying electro-anatomic relationships in the heart. Understanding the relationships between anatomic and electrophysiologic abnormality is appropriate not only for diagnosis, therapy, and prognosis in patients with primum AVSD but also for understanding the developmental relationship between the conduction system and heart structures, in general. This article presents a review of the anatomical and electrophysiologic characteristics of patients with primum AVSD and provides recent knowledge of electroanatomical relationships of the heart.
Abstract Background Patients with ostium secundum atrial septal defects (ASDs) were studied to determine the prevalence of Selvester anteroseptal myocardial infarction QRS points, and to test the ...hypothesis that there is a relationship between these criteria and thinning and/or scarring of the inter-ventricular septum (IVS). Methods Demographic, electrocardiographic (ECG), and cardiac magnetic resonance imaging (CMR) data were acquired on 46 patients with a secundum ASD closed percutaneously. Selvester QRS scoring on patient ECGs was performed for areas representing the anteroseptal region of the left ventricle (LV). The IVS to LV free wall thickness ratio was used to assess thinning of the IVS while late gadolinium enhancement (LGE) of the IVS was used for scarring; both using CMR. Results Twenty-four (52%) patients scored Selvester QRS points in the anteroseptal region with a mean score of 2.6 ± 1.8. The mean IVS/LV free wall thickness ratio at the basal level and mid-ventricular level was 1.1 ± 0.3 and 1.3 ± 0.3, respectively. There was no association of Selvester QRS points with IVS/LV free wall ratio at the basal ( p = 0.59) or mid-ventricular ( p = 0.13) levels. The one patient with LGE in the IVS had 4 Selvester anteroseptal QRS points. Conclusion The results of our study demonstrate that in our patient population there is a 52% prevalence of Selvester anteroseptal QRS points which are due to thinning and/or scarring of the IVS in only one patient.
Abstract Background Arrhythmias are frequent causes of morbidity and mortality in patients with single ventricle physiology after Fontan operation. The aim of this study was to evaluate which type of ...Fontan procedure—lateral tunnel (LT) or extracardiac conduit (EC)—provides superior outcomes related to the problem of early postoperative and 1-year follow-up arrhythmias. Methods We retrospectively analyzed the incidence, types, and duration of rhythm disorders in 101 consecutive patients who received either LT (n = 60) or EC (n = 41) between April 1997 and March 2006 in Slovak Children's Cardiac Center, Bratislava (Slovakia). Weight, age, sex, and the type of heart morphology did not differ significantly between the 2 groups. The rhythm was monitored and documented perioperatively and postoperatively with standard electrocardiogram (ECG) recording and continual ECG monitoring. Duration of extracorporeal circulation, duration of aortic crossclamp and hemodynamic variables were analyzed with respect to the development of early arrhythmias in both groups. Twenty-four–hour ECG Holter monitoring (DMS 300-7, Holterreader, Producer DMS, Nevada, USA) was used to detect arrhythmias at the 1-year follow-up. Results Early postoperative rhythm abnormalities were identified in 31 patients (52%) who underwent LT and in 22 patients (54%) who underwent EC. The most frequent type of rhythm disturbance was junctional rhythm in both groups. The bivariate analysis revealed that there was no significant difference in the incidence, type, or duration of early onset arrhythmias between the 2 groups. Although, there was no significant difference in the duration of arrhythmia since the admission form the operating room. The need of aortic crossclamp was significantly lower in EC group ( P < .001). However, this did not correlate with lower incidence of early onset arrhythmias with EC modification. At the 1-year follow-up, the prevalence of arrhythmias was similar in both groups. Conclusions Extracardiac conduit as compared with LT does not provide superior outcomes related to the problem of early and 1-year onset arrhythmias. Other factors than the risk of early postoperative and early follow-up arrhythmias should be considered in surgical preference of modification strategy.
Abstract Background Vectorcardiographic QRS loops illustrate the electrical activation of the left ventricle (LV) in 3-dimensional space; however, the individual variability in these loops is not ...well understood. The left bundle-branch fan distributes the initial activation to the LV and has been shown to distribute its fascicles between the LV papillary muscles. Computer models of LV activation using papillary muscle as the initial electrical activation points accurately predict QRS duration and frontal plane axis. Methods Twelve healthy adults received standard 12-lead electrocardiograms and 1.5-T cardiac magnetic resonance imaging. A software developed by ECG-TECH Corp (Huntington Station, NY) generated 3-dimensional QRS vector loops for each subject. Short- and long-axis papillary muscle positions were measured for each subject using cardiac magnetic resonance images. A theoretical plane equidistant from the endocardial origins of each papillary muscle was constructed. Vectors perpendicular to the QRS vector loop and the theoretical plane termed the plane identifier were used for comparison. Spearman rank correlation was used to compare the azimuth and elevation of the plane identifiers of the QRS vector loop and the theoretical plane. Results No correlation was found between the azimuth or elevation of the theoretical plane and the QRS vector loops with Spearman rank correlation coefficients of ρ = 0.11 ( P = .71) and ρ = 0.22 ( P = .49), respectively. Subgroup analysis by QRS vector loop morphology (planar vs nonplanar, narrow vs wide) also demonstrated no correlation. Conclusions Modeling the activation of the LV based on papillary muscle position alone may be overly simplistic. Better understanding of what other factors contribute to individual variation in LV activation will help develop a more useful theoretical model.
PDF