Two-dimensional echocardiographic assessment of right ventricular volume in children with congenital heart disease

The ability of 2-dimensional echocardiography to measure right ventricular (RV) volume and ejection fraction was assessed in 22 children with congenital heart disease. From the apical 4 chamber 2-dimensional echocardiographic image, the long-axis length of the right ventricle was measured and the area planimetered. On the anteroposterior and lateral cineangiocardiographic planes, the right ventricle was separated into 2 parts: RV sinus and outflow tract. The longest length, inflow tract length, and area of the sinus were measured from biplane cineangiographic views. The echographic long-axis length correlated well with the longest length of the RV sinus measured from both anteroposterior and lateral cineangiographic views at both end-systole and end-diastole. Moreover, the echographic area correlated well with the sinus area obtained from both cineangiographic views. From these regression analyses, the echographic long axis length and area were corrected to the angiographie longest length and area of the sinus. The new corrected echographic longest length and area were applied to 3 formulas (2 biplane and 1 uniplane) to calculate the sinus volume of the right ventricle. Total RV volume was then derived from the sinus volume. RV volumes and ejection fraction determined by 2-dimensional echocardiography were compared with those obtained from biplane cineangiography using Simpson's rule method. All formulas tested predicted RV volumes and ejection fraction with equal accuracy. Thus, 2-dimensional echocardiography can assess RV volume and ejection fraction in children with congenital heart disease.     

Two dimensional echocardiographic characteristics of double outlet right ventricle.

The reliability was evaluated of two dimensional echocardiography in distinguishing double outlet right ventricle from other anomalies of the great arteries. Accordingly, a combined retrospective and prospective study was conducted in 13 children with double outlet right ventricle, 12 with tetralogy of Fallot, 13 with complete d-transposition of the great arteries, 5 with congenitally corrected I-transposition and 2 with truncus arteriosus. Echographic findings using a standard long axis view in all subjects with double outlet right ventricle included (1) inability to identify a great artery arising from the left ventricle, and (2) lack of continuity between the anterior mitral leaflet and any semilunar valve. In the short axis view constant findings were (1) simultaneous imaging of both great arteries in an anterior location with the ventricular septum identified posteriorly on sweeping into the left ventricle, and (2) lack of a clockwise wraparound of the aorta by the right ventricular outflow tract. Imaging revealed that the great arteries were side by side in seven patients d-malposed in three and l-malposed in two. A modified left precordial tomographic view demonstrated both great arteries arising from the right ventricle in four of nine patients not treated surgically. In four patients with surgically repaired double outlet right ventricle, the left ventricular outflow tract had a tunnel-like configuration in the long axis view. These findings were diagnostic of double outlet right ventricle in all patients and accurately differentiated the malformation from other anomalies of the great arteries.     

Mitral valve E point to ventricular septal separation in infants and children

This investigation establishes heretofore unavailable norms that permit clinical application of mitral valve E point to ventricular septal separation (EPSS) as an ejection phase index in infants and children. The study consisted of 105 normal subjects (1 day through 15 years of age, mean 7.4 years) and 67 patients of comparable age. Fifty-seven patients had increased left ventricular (LV) volume with normal function (ventricular septal defect or patent ductus arteriosus) and 10 patients had increased LV volume with depressed function (dilated cardiomyopathy). In normal subjects, EPSS was 2.5 ± 1.7 mm and “normalized” EPSS, that is, the ratio of EPSS to end-diastolic dimension ($\text{EPSS}\text{EDD}$), was 0.08 ± 0.06 (mean ± standard deviation); there was no correlation between either of these indexes and age, body surface area, height or weight. In patients with ventricular septal defect or patent ductus arteriosus, or both, the EPSS and $\text{EPSS}\text{EDD}$ were similar to those of normal subjects (3.2 ± 2.3 mm and 0.09 ± 0.06 mm, respectively). In patients with dilated cardiomyopathy, these indexes were significantly increased (p > 0.05) ($\text{EPSS}\text{16.5 ± 5.1}\text{mm;}\text{EPSS}\text{EDD}\text{0.39 ± 0.09}$). The data provide normal values for EPSS and $\text{EPSS}\text{EDD}$ in infants and children and show that these indexes are independent of age, body surface area, height or weight. Mitral valve EPSS and $\text{EPSS}\text{EDD}$ can now be used in pediatric echocardiography as a simple, practical and accurate means of separating normal from abnormal LV function.     

Two-dimensional echocardiographic evaluation of discrete subaortic stenosis from the apical long axis view

M-mode and standard two-dimensional (2DE) left parasternal long axis echocardiographic examination of the left ventricular outflow tract (LVOT) was evaluated exclusively with respect to its utility in identifying discrete subaortic stenosis (SUB-AS). Important details of the anatomy of the subaortic area may also be obtained from 2DE apical long axis imaging. Accordingly, 18 patients with discrete SUB-AS were prospectively evaluated by M-mode and 2DE. The M-mode findings included narrowing of the LVOT and early systolic closure of the aortic valve. However, these findings were variable and highly dependent upon scan speed, fluid flow dynamics, and beam angulation. 2DE findings varied using the standard long axis view at the left parasternal border, depending upon the type of obstruction present. A discrete membrane produced linear echoes adjacent and parallel to the interventricular septum beneath the aortic valve. Fibromuscular obstruction produced a localized dense ridge of echoes in the LVOT. These findings were not apparent in five patients studied. In these patients, the 2DE apical long axis view was employed to image the subaortic area. From this tomographic crosssection a fibrous membrane was imaged as a linear echo parallel to the aortic valve. The membrane extended across the LVOT from the ventricular septum to the anterior leaflet of the mitral valve. The 2DE apical long axis view therefore provides an additional approach in the evaluation of patients with discrete SUB-AS.     

M mode and cross-sectional echocardiographic features of flail posterior mitral leaflets

Seventeen patients with accepted M mode echocardiographic criteria for flail mitral leaflet were studied. M mode echocardiograms revealed characteristic disordered mitral valve motion: (1) 16 (94 percent) had chaotic diastolic mitral motion; (2) 14 (82 percent) had systolic mitral flutter; (3) 14 (82 percent) had systolic left atrial echoes; and (4) 12 (71 percent) had systolic mitral valve prolapse. In 8 patients (47 percent) all four findings were present, with three findings present in 16 (35 percent) and two findings present in 13 (18 percent); none had fewer than two findings. Cross-sectional echocardiographic studies in 10 patients revealed a systolic whipping motion of the posterior mitral leaflet into the left atrium in all, abnormal systolic mitral coaptation in all and an abnormal mass of systolic left atrial echoes in 4. None of the first three M mode criteria were observed in 230 patients with uncomplicated “mid systolic click-late systolic murmur” syndrome; cross-sectional echocardiography in 30 of 230 patients revealed normal systolic mitral coaptation and no systolic whipping of the tip of the posterior mitral leaflet into the left atrium.     

Two-dimensional echocardiographic evaluation of dilated cardiomyopathy in children

This study examines and quantitates left ventricular (LV) short-axis 2-dimensional (2-D) echocardiograms of 16 normal control subjects and 19 patients who presented with clinical features suggestive of myocarditis leading to severe myocardiopathy. Of the 19 patients, 8 died or had cardiac transplantation: 9 were studied in the chronic phase and 10 in the acute phase. The endocardial surface of the LV short-axis image was digitized at chordal level at end-diastole and end-systole. Digitized traces in systole and diastole were superimposed. The cavity area of systole and diastole was determined and expressed as the percent systolic area reduction ratio. In the control subjects, the left ventricles were round in systole and diastole, contracted concentrically, and had a mean percent systolic area reduction of 53% (range 43 to 67). The left ventricle was not round in systole in the patients with myocarditis, and in 15, only the ventricular septum contracted significantly. Three patients had nonconcentric contraction, and regional contraction was more difficult to judge. The systolic area reduction ratio for the patients was 11 % (range 1 to 33), with no overlap with control subjects (p <0.001). Our results suggest that myocarditis more severely affects the LV free wall than the septum. In chronic patients, LV contraction remained markedly impaired. Quantitative evaluation of short-axis 2-D echocardiograms is a useful and sensitive technique for assessing damage due to presumed myocarditis.     

Clinical problems of postoperative pulmonary vascular disease

The younger the patient with a large left to right shunt at the time of operation, the greater the likelihood that pulmonary vascular resistance will fall to normal thereafter. In older patients, the degree to which the pulmonary vascular resistance is elevated before operation is a critical factor determining operability and prognosis. Patients at particularly high risk for the development of significant pulmonary vascular obstruction early in life are those with certain forms of cyanotic congenital heart disease, such as complete transposition of the great arteries with ventricular septal defect and patent ductus arteriosus, and truncus arteriosus. Other conditions in which pulmonary vascular obstruction appears to progress rapidly include large ventricular septal defect, complete atrioventricular canal defect and left to right shunt lesions in an environment of high altitude or associated with unilateral pulmonary arterial absence of the Down's syndrome. In this report the framework is reviewed for recognizing that important pre- and postnatal modifiers of the pulmonary vascular bed may be lesion-dependent. Thus, the growth and development of the pulmonary vascular bed during fetal and early postnatal life, as well as the morphologic alterations described in detail by Heath and Edwards, are likely to determine the ultimate intensity and magnitude of pulmonary vascular obstruction. Commentary is also provided concerning the management of patients with high pulmonary vascular resistance during pregnancy and delivery, their response to exercise, and the possibility of medical treatment designed to reduce pulmonary vascular resistance, and perhaps prolong life and enhance its quality.     

The physiologic mechanisms of cardiac and vascular physical signs

Examination of the heart and circulation includes five items: 1) the patient's physical appearance, 2) the arterial pulse, 3) the jugular venous pulse and peripheral veins, 4) the movements of the heart-observation, palpation and percussion of the precordium, and 5) auscultation. This report deals with specific examples that relate cardiac and vascular physical signs to their mechanisms, focusing on each of the five sources. It draws liberally on early accounts, emphasizing that modern investigative techniques often serve chiefly to verify hypotheses posed in the past.     

Relation of coronary arterial spasm to sites of organic stenosis

Among 63 patients with Prinzmetal's variant angina, coronary arterial spasm responsible for attacks of variant angina was documented arteriographically in 9 patients. In each observed episode (11 attacks in nine patients), coronary spasm producing myocardial ischemia occurred at and was superimposed on a site of preexisting organic stenosis. Measurements of normal portions of "spastic" and "nonspastic" vessels suggested a generalized uniform constriction of all major coronary arteries during attacks, with "spasm" limited to the site of an organic lesion in most cases. In two cases the magnitude of constriction in all vessels was consistent with generalized coronary hypercontractility or spasm. Among 104 patients with organic coronary artery disease and documented single vessel coronary spasm (foregoing 9 patients combined with 95 others from published reports), there were 70 patients with essentially single vessel organic coronary disease in 90 percent of whom the spasm involved the diseased vessel. Of 60 cases abstracted from the literature in which the relation of coronary spasm to the site of organic disease was described, 88 percent had the spasm causing ischemia localized to the site of an organic lesion. Hypotheses attempting to describe the pathophysiologic aspects of coronary spasm in variant angina must account for the intimate association of spasm with sites of organic stenosis in the majority of cases.     

New stable temporary atrial pacing loop

Temporary right atrial pacing is a useful but underutilized technique because of instability of the pacing electrodes. To circumvent this problem, a new method of pacing was Invented. A loop-mounted electrode structure, originally devised for measurement of blood flow, has been adapted as a temporary right atrial pacer. It is rapidly and easily introduced into the right atrium through a catheter. Once in place, the catheter is removed leaving only the loop in place. It has been used successfully in 14 of 16 patients, in 5 for periods of 3 to 15 days. The methods of construction and clinical experience are described.     

Increased right ventricular wall thickness on echocardiography in amyloid infiltrative cardiomyopathy

In six patients with clinically significant amyloid infiltrative cardiomyopathy, echocardiographic right ventricular anterior wall thickness was significantly increased (mean 7.5 ± 2.3 mm; range 5 to 10 mm). This finding in conjunction with the previously described abnormalities of the left ventricle (symmetric increase in wall thickness, diffuse hypokinesia, and small to normal left ventricular diastolic dimension) is consistent with the findings of a diffuse myocardial infiltrative process and should minimize confusion with constrictive pericarditis.     

Role of chordae tendineae in mitral valve opening: two-dimensional echocardiographic evidence

Study of 16 normal and 33 flail mitral valves provides evidence of the active participation of chordae tendineae in mitral valve opening. The normal valves have straight chordae at all phases of opening. During isovolumic relaxation and progressive opening phases, the smooth configuration of the mid-anterior mitral leaflet is broken by a sharp outward "tenting." This tenting is localized at chordal insertions, reflecting significant tension at these points. Flail mitral valves allow comparison of opening motion between mitral segments with normal chordal attachment and flail segments without chordal support. Posterior flail leaflets demonstrate delay in initiation of opening motion relative to the normal anterior leaflet. The most dramatic examples of this delay reveal a maximal opening excursion of the anterior leaflet before the flail posterior leaflet initiates opening motion. The untethered free margins of opening flail anterior leaflets produce the appearance of the flail segment trailing the body of the anterior leaflet with a sharp break in leaflet contour between the supported and unsupported segments. These configurational expressions of mitral valve opening are inconsistent with a passive hemogenic mechanism. They support an active myogenic process mediated through direct traction on the valve by the chordae tendineae.     

Immune suppression of hematopoiesis.

Recent evidence suggests that immune mechanisms can injure proliferating hematopoietic precursor cells in the bone marrow. These may involve either humoral antibody or cell-mediated cytotoxic mechanisms. Immune injury can result in a variety of bone marrow failure syndromes. Immunologically induced abnormalities or blood cell production may be restricted to a single series, such as erythrocyte or granulocyte precursors, or may involve several hematopoietic lines; clinical manifestations reflect the cell line or lines that are injured. Immune suppression of hematopoiesis has now been described in pure red cell aplasia, immune panleukopenia, systemic lupus erythematosus, atypical cases of aplastic anemia and miscellaneous other hematologic diseases.     

Development and regression of increased ventricular mass

This report deals with increased cardiac mass in the light of the following variables: normal ventricular growth (embryo, fetus, neonate and child), the response to work loads (hemodynamic stress) and hypoxia, the cell responses of hyperplasia (increase in cell number), hypertrophy (increase in cell size) and the type of cell (muscle or connective tissue), the age or maturity of the myocardium at the time the hemodynamic or hypoxic stress is imposed, and the biochemistry, ultrastructure and functional morphology (modeling) of the ventricles in response to volume or pressure overload. The desirable physiologic adaptations to work loads are characterized, and the transition from physiologic to pathologic states is examined, comparing and contrasting increased ventricular mass in patients and in trained athletes. Regression of increased ventricular mass is then discussed, first at the cell level (hypertrophy/hyperplasia; muscle cell/connective tissue cell), then at the organ level. The requirements for maintaining or establishing normal ventricular function after removal of overload are reviewed, together with such variables as the type and duration of preoperative hemodynamic stress, the right versus the left ventricle and the relative rates of contractile protein synthesis and degradation.     

Adenovirus infection in the immunocompromised patient

Illness associated adenovirus infection is described in 15 immunocompromised patients. Patients were immunocompromised by severe underlying disease, immunosuppressive or corticosteroid therapy or by age (prematurity). Evidence of adenovirus infection was obtained by either viral isolation or, in two cases, characteristic adenovirus inclusion bodies at postmortem study.All clinical illness was associated with high fever (temperature >39 °C). Eighty per cent of the patients had severe systemic complaints including malaise, lethargy, fatigue and night sweats; a similar number of gastrointestinal symptoms. Pulmonary complaints were described in 11 of 15 cases and included cough (67 per cent) and tachypnea (53 per cent). Roentgenologic evidence of pneumonia was demonstrated in 12 of 15 patients (80 per cent). Elevation of serum hepatic enzyme levels (serum glutamic pyruvic transaminase (SGPT)) occurred in eight of 11 patients (73 per cent) and was moderate to severe (serum glutamic pyruvic transaminase >450 IU/liter) in five of 11 (45 per cent). Nine patients died; seven after a rapid downhill course and two after a prolonged illness. Evidence of adenovirus infection microscopically by autopsy in the lung, liver or both is demonstrated in four patients with fulminant systemic illness. Adenovirus infection should be considered in the etiology of severe overwhelming illness in the immunocompromised host.