Evolution of Pediatric Cardiology over the Last 50 Years-Part III

Citation: Rao PS (2021) Evolution of Pediatric Cardiology over the Last 50 Years Part III. Int J Clin Cardiol 8:225. doi.org/10.23937/2378-2951/1410225 Accepted: May 12, 2021: Published: May 14, 2021 Copyright: © 2021 Rao PS. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Documentation of diagnosis of Ebstein's anomaly of the left atrioventricular valve with congenital corrected transposition of the great arteries by intracavitary electrocardiography [18], ECG features of tricuspid atresia [19,20] and etiology of left axis deviation in patients with tricuspid atresia [19][20][21] were also presented.

Echocardiography
To a large extent, the author has self-learned the echocardiography and Doppler recording techniques as well the skills of interpretation of such recordings; these endeavors helped the author to participate and perform several echocardiographic investigations. The echo studies include, usefulness of echocardiography in estimating the magnitude of left-to-right shunt in isolated ventricular septal defects (VSDs) (Figure 4) [22], usefulness of contrast echocardiography in the diagnosis of anomalous drainage of the right superior vena cava to the left atrium ( Figure 5) [23,24], identification of pitfalls of m-mode echocardiography in the evaluation of the aortic root in left ventricular hypoplasia syndromes [25].

Introduction
The author has just written a book on the evolution of the specialty of Pediatric Cardiology over the last 50 years [1]. The intent of this review is to present a summary of this book. Because of large amount of this material, the review is separated into four parts. In these first and second parts, transcatheter interventions (balloon angioplasty/valvuloplasty procedures and percutaneous occlusions) were appraised. In this paper, electrocardiography, echocardiography, and cardiac catheterization will be reviewed.

Electrocardiography
In this review, contributions of the author pertaining to electrocardiography were examined. These contributions were: A study of normal Frank and McFee vectorcardiograms in the normal adolescent [2], distinguishing right ventricular hypertrophy from postero-basal left ventricular hypertrophy [3], identifying possible cause of alternating failure of mechanical to electrical depolarization (AFORMED) phenomenon [4], examination to see if racial variations in electrocardiograms and vectorcardiograms between black and white children exist and if so, the causes of such variation [5,6], document resolution with medications of congestive cardiomyopathy due to chronic tachycardia ( Figure 1) [7], changes in the electrocardiogram (ECG) after balloon pulmonary valvuloplasty ( Figure 2) [8,9], utility of electrocardiogram in delineating atrial ( Figure 3) and ventricular situs in patients with dextrocardia and heterotaxy syndromes [10][11][12][13][14], and an appraisal of arrhythmias in children [15][16][17].   The location of the P vector (axis) in the frontal plane is shown for situs solitus (+45°) and situs inversus (+135°). A P vector between 0° and -90° is called coronary sinus rhythm and is not helpful in atrial situs assignment [10].      at six months after angioplasty are shown. Note the reduction of peak Doppler flow velocity from C to D, with further fall in E. Also note that the diastolic flow is seen throughout the entire diastole (pandiastolic) prior to angioplasty (C), and is seen only is early diastole immediately after angioplasty (D). At six-month follow-up (E), there was no diastolic flow at all [37]. pler in the prediction of pressure gradients across aortic coarctation [38], description of foramen ovale and transatrial Doppler velocity patterns in the normal fetus ( Figure 10) [39], establishing the correlation of shunt flow and angiographic size to stretched diameter of the atrial septal defect by echocardiograms [40], echocardiographic assessment of balloon-stretched diameter of secundum atrial septal defects [41], development of echocardiographic predictors of success of buttoned device closure of atrial septal defect [42], pointing out of limitations of echo in complete assessment of mixed type of total anomalous pulmonary venous connection load reduction in the treatment of primary myocardial disease ( Figure 6, Figure 7 and Figure 8) [33].
Also reviewed were usefulness of echo-Doppler studies in the assessment of the results of balloon pulmonary valvuloplasty [34], utility of Doppler studies in the estimation of pressure gradients across the pulmonary valve in pulmonary stenosis [35], appraisal of Doppler echocardiography in non-invasive diagnosis of heart disease in children [36], echo-Doppler studies in the appraisal of the results of balloon procedure for coarctation of the aorta (Figure 9) [37], importance of Dop-  A and B). In a patient with elevated PA pressure the PV wedge pressures is mildly damped with slightly lower magnitude when compared with the PA pressure (C). The pulse pressure is also lower in the PV wedge position. Note that both the PA and PV wedge pressure tracings demonstrate pulsus alternans in a patient with congestive heart failure (C) [55].  cardiac catheterization and selective cine-angiography were discussed. These are: Correlating pulmonary venous wedge pressures with pulmonary arterial pressures ( Figure 11 and Figure 12) during cardiac catheterization [55], advocacy of femoral venous route for cardiac catheterization in pediatric patients infants [56], report of systemic venous anomalies and partial heterotaxia in a child with normal heart [57], examining the concepts with regard to pressure and energy in cardiac chambers both in terms of pressure gradient in the absence of obstruction/stenosis [58] and lack of pressure gradient in the presence of multiple obstructions in series [59], status of cardiac catheterization in children in the mid-1970s [60], demonstration of growth of hypoplastic ri- [43], echocardiographic follow-up results of buttoned device occlusion of atrial septal defect [44], review of ultrasound studies [45][46][47], collaborative echo-Doppler studies [48][49][50], echocardiographic evaluation of the results of balloon pulmonary valvuloplasty [51], editorials on echo topics, aneurysm of the ventricular septum producing pulmonary outflow tract obstruction in the morphologic left ventricle in corrected transposition of the great arteries [52][53][54] and echo descriptions of CHDs.

Cardiac Catheterization and Selective Cineangiography
The contributions of the author in the procedures of  with pulmonary atresia, with multiple aortopulmonary collateral arteries (MAPCAs); the right heart catheter (C) was advanced into the ascending Ao via the VSD. Note that multiple collateral vessels were seen, but there is no clear demonstration of these vessels; b) The same infant's cineangiogram, also in postero-anterior view, obtained by balloon (B) occlusion descending aortography, demonstrates several collateral vessels more clearly than can be seen in a. c) A delayed phase of b demonstrates the right (RPA) and left (LPA) pulmonary arteries. Dao: descending aorta [69]. ght ventricle by angiography following valvotomy for severe pulmonary stenosis with intact ventricular septum [61], role of intracavitary electrocardiography in the diagnose Ebstein's anomaly of the left atrioventricular valve in children with congenital corrected transposition of the great arteries [18], demonstration of utility of pulmonary vein wedge angiography in visualization of obstructed pulmonary arteries ( Figure 13) [62], growth phenomenon as a mechanism for development of kinking of the right pulmonary artery following Waterston anastomosis ( Figure 14) [63], and documentation of a new complication of the Waterston anastomosis, namely false aneurysm of the right pulmonary artery [64].
The presentation also included manifestation of non-opacification of patent ductus arteriosus in patients with large proximal shunts [65], outcome of intra-arterial injection of heparin on the complications associated with percutaneous arterial catheterization [66], depiction of a new technique of left ventricular and aortic catheterization and angiography via a patent ductus arteriosus [67,68], value of balloon occlusion aortography in demonstrating proximal structures and aorto-pulmonary collateral vessels ( Figure 15) [69], and documentation of aneurysms of the membranous ventricular septum resulting in pulmonary outflow tract obstruction in congenitally corrected transposition of the great arteries both in patients with levocardia ( Figure 16) [52] and those with dextrocardia [53,54].