Echocardiographic differentiation of partial and complete atrioventricular canal

Retrospective examination of echocardiograms was performed in 34 patients with persistent atrioventricular (A-V) canal who had undergone cardiac catheterization. Characteristic findings in 16 patients with partial A-V canal were lack of continuity of mitral and tricuspid valves, paradoxical interventricular septal motion, definite E and A waves of the mitral valve anterior leaflet (MVAL) echoes and late systolic anterior motion of the mitral valve. Eighteen patients with persistent A-V canal had an interventricular communication and were classified as having the complete form. They characteristically had continuous mitral and tricuspid valves, normal interventricular septal motion, disorganized MVAL echoes, and normal systolic mitral valve motion. Combining these findings allowed differentiation of 31 of the 34 patients (91%) as having partial or complete A-V canal. Determining the presence of a VSD from loss of interventricular septal echoes was unsatisfactory. The severity of mitral insufficiency could not be estimated from echocardiograms of our patients with partial A-V canal.     

Echocardiographic classification of complete atrioventricular canal defects

M-mode echocardiographic records of 26 patients with surgically proven complete atrioventricular canal defect were reviewed. Fragmentation of the interventricular septum and anterior displacement of the mitral annulus into the left ventricular outflow tract were noted in all patients. In 25 of 26 a common atrioventricular valve leaflet echo could be identified in the left ventricular outflow tract at the area of the crest of the interventricular septum. Recordings of echographic scans performed in the area of the left ventricle demonstrated separate “mitral” and “tricuspid” contributions to atrioventricular valve echoes in all 13 patients with type A defect, and a single common atrioventricular valve leaflet in 10 of 11 patients with type C complete atrioventricular canal. Two patients with type B defect had findings intermediate between these two patterns. M-mode echocardiography presumptively diagnosed complete atrioventricular canal in all 26 patients and diagnosis was definitive in 25 of 26. In addition, echocardiographic atrioventricular valve patterns permitted anatomic classification in the large majority of cases.     

Ultrasound in the diagnosis of congenital heart disease

In addition to recording the motion of the mitral, tricuspid, aortic, and pulmonic valves, echocardiography can identify right and left ventricular cavities and the interventricular septum. Disorders such as atrial-septal defect, valvular and subvalvular aortic stenosis, pulmonic stenosis, Ebstein's anomaly of the tricuspid valve, and the hypoplastic left-heart syndrome can readily be evaluated by echocardiography. In tetralogy of Fallot and truncus arteriosus, discontinuity between the anterior aortic wall and septum with overriding aorta has been demonstrated. Doubleoutlet right ventricle is associated with posterior aortic wall and mitral valve discontinuity. In disorders such as single ventricle, tricuspid atresia, and endocardial cushion defect with common A-V canal, echocardiographic demonstration of the absence of the interventricular septum has provided the clinician with valuable information.Newer techniques such as compound-B ultrasonography, which produces a two-dimensional cross-sectional image of intracardiac structures, and multiscan echocardiography will enhance the use of conventional echocardiography by providing a more accurate anatomic display of cardiac chambers and outflow vessels.     

Positional abnormalities of atrioventricular valves in transposition of the great arteries including double outlet right ventricle, atrioventricular valve straddling and malattachment.

Positional abnormalities (straddling or overriding) of the atrioventricular (A-V) valves were studied using angiographic, sector scan echocardiographic and postmortem anatomic data in 10 patients with transposition of the great arteries including double outlet right ventricle. Group I included six patients with tricuspid valve abnormalities. This group was further classified into: (a) patients with anular straddling and abnormal attachment of portions of the tricuspid leaflets in the left ventricle (malattachment) or on the ventricular septum, or both (four patients with d-transposition of the great arteries and hypoplastic right ventricle); and (2) patients with malattachment of portions of the tricuspid valve leaflet to the crest or left ventricular surface of the septum (septal malattachment) without significant anular straddling (two patients with d-transposition of the great arteries).Group II included four patients with mitral valve abnormalities without significant anular straddling, further classified into: (1) patients with septal malattachment of the portions of the mitral valve to the crest and right ventricular surface of the ventricular septum (two patients with double outlet right ventricle); and (2) patients with ventricular malattachment of portions of the mitral valve leaflets to the papillary muscles in the right ventricle (two patients with ventricular septal defect and discordant criss-cross atrioventricular connections).On the basis of these observations and reported experience, two main types of positional abnormalities of the A-V valves were recognized: (1) anular straddling in which the A-V anulus straddled the ventricular septum above the contralateral ventricle, together with ventricular leaflet malattachments, and (2) leaflet malattachment of either the septal or ventricular type without significant straddling of the valve anulus. Angiocardiography and sector scan echocardiography helped to identify these abnormalities of the A-V valves.     

Echocardiography in atrioventricular canal defect: A clinical spectrum

Echocardiographic examinations were performed in 30 children with atrioventricular (A-V) canal defect to determine the diagnostic value of recording A-V valve motion. Although a wide spectrum of abnormal movement was observed, four main diagnostic types emerged. Type 1, prolonged mitral-septal approximation during diastole, resulted from anterior displacement of the cleft anterior mitral leaflet. Type 2, the most diagnostic motion, was recorded when the common anterior A-V leaflet traversed the interventricular septum. Type 3 motion reflected posterior displacement of the septal tricuspid leaflet, which appeared to arise from the interventricular septum. Normal posterior diastolic motion of the septal leaflet was never recorded. Type 4, double contour of the mitral valve during systole and marked duplication of the systolic image, corresponded to irregularities in the mitral valve. When these patterns are recorded in a patient with congenital heart disease the diagnosis of A-V canal defect can be made with confidence.     

Overriding tricuspid valve: Echocardiographic and angiocardiographic features

Eight cases are presented in which the diagnosis of overriding of the tricuspid valve was made during life and the electrocardiographic, echocardiographic and angiographic features of this defect are presented. Four of the patients had dextrotransposition of the great arteries, three had normally related great arteries and one had corrected transposition. In each case there was hypoplasia of the right ventricle and a ventricular septal defect of the atrioventricular (A-V) canal type. The electrocardiogram in the cases with d-transposition was characterized by diminished right ventricular forces, left ventricular hypertrophy and a superior leftward frontal plane axis. The echocardiogram in seven cases demonstrated a septal leaflet of the tricuspid valve opening posterior to the septum into the left ventricle. In four cases the anterior leaflet of the tricuspid valve was shown crossing the plane of the interventricular septum as it opened in diastole. The diagnosis in five cases was made angiographically by a left ventricular injection in the left anterior oblique projection. In this view the septum was viewed tangentially and in diastole the negative silhouette of the tricuspid valve was seen straddling the interventricular septum. The presence of an overriding tricuspid valve can greatly complicate repair of intracardiac defects. The diagnosis of this A-V valve anomaly can be accurately made with the use of echocardiography and selective left ventricular angiography.     

Echocardiography in Ebstein's anomaly (author's transl)

Results about an echocardiographic study of 20 patients with Ebstein's anomaly diagnosed by cardiac catheterization and angiography, are referred. In 8 patients an echocardiogram and phonocardiogram were recorded and in five patients an echocontrast examination was performed. The echocardiographic features constantly recorded in Ebstein's anomaly are represented by anterior chamber dilatation, interventricular septum paradoxical movement, anterior tricuspid leaflet wide excursion, decreased diastolic closure rate and delayed closure of tricuspid valve compared to mitral valve. The reduced left ventricular dimension and frequent incidence of "hammock-like" shape of mitral valve during systole and reduced diastolic closure rate of anterior mitral leaflet are pointed out. Possible causes of anterior chamber dilatation, of interventricular septum paradoxical motion and delayed tricuspid closure are discussed. According to the previous study no echocardiographic pattern is surely diagnostic of the disease by itself; a delayed tricuspidal closure (more than 70 msec) when associated to an anterior tricuspid leaflet wide excursion and decreased E-F slope, is of particular value for diagnosis.     

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.     

Straddling and overriding atrioventricular valves: morphology and classification.

Fifty-seven hearts are described in which either the orifice or tension apparatus of an atrioventricular (A-V) valve was related to both sides of a septum in the ventricular mass. In most of the hearts both the orifice overrode the septum and the tension apparatus straddled the septum. In some hearts straddling of the tension apparatus was present in the absence of overriding of the anulus while in two hearts the anulus overrode in the absence of straddling. Hearts were observed in which the chamber receiving all of one valve and the straddling portion of the other valve had either right or left ventricular morphologic features, and in each type the chamber receiving only part of the straddling valve was found either to the right or the left. When the straddling valve was morphologically a tricuspid valve it always straddled the posterior part of a septum that never extended to the crux; when it was morphologically a mitral valve it always straddled the anterior part of a septum that did extend to the crux. This arrangement was found irrespective of the relations of the chambers.Four basic groups were therefore defined: straddling of the mitral and tricuspid valves in the setting of A-V concordance and discordance, respectively. However, the degree of override of the straddling valve was frequently such that the A-V connection present was double inlet ventricle rather than concordance or discordance. Indeed, in each group a series of anomalous hearts was found between the extremes of concordance or discordance and double inlet. In categorizing the A-V connections, these series were divided at their mid points. The hearts with double inlet connections were considered univentricular hearts and their chambers described accordingly. In each series hearts were found with unequally committed common valves that were virtually identical to the hearts with straddling right or left valves. They were therefore included in the study as were two hearts in which both right and left valves straddled. Examination of the conduction tissues in examples of each series showed that the position of the connecting node depended on whether or not the septum extended to the crux, anterior systems being found when it did not and either anterior or regular systems when it did, the latter variation depending on the A-V connection present. The study shows that straddling or overriding valves can be easily catalogued if attention is paid to the A-V connection and the morphologic features and relations of the ventricular chambers.     

Left and right ventricular morphology in complex congenital heart disease defined by two dimensional echocardiography

The ability of two dimensional echocardiography to define right and left ventricular morphology in congenital heart disease was examined in 19 patients with discordant ventricular connections and abnormal relations, but with two ventricles and two unambiguous atrioventricular (A-V) valves. The two dimensional echocardiographic criteria used to identify a chamber as having right morphology were (1) an irregular endocardial surface, (2) insertion of chordae tendineae into the ventricular septum, (3) presence of an infundibulum, (4) a triangular-shaped ventricular cavity, (5) observation of a moderator band, and (6) recognition of the A-V valve as tricuspid. The two dimensional echocardiographic criteria for a left ventricular morphology were (1) a smooth endocardial surface, (2) presence of two discrete papillary muscle groups, (3) an ellipsoid-shaped ventricular cavity, and (4) recognition of the A-V valve as mitral.Identification of the associated A-V valve as mitral or tricuspid was the most reliable criterion, defining each ventricle in all 19 patients. The nature of chordal attachment and papillary muscle insertion successfully identified all left-sided and posteriorly related ventricles and 9 of the 19 anterior ventricular chambers. Other criteria were less useful although, when observed, they confirmed the ventricular type.     

Unusual echographic manifestations of right and left heart myxomas.

Although echocardiography has provided a useful noninvasive means for detecting cardiac myxomas, the ultrasound manifestations of these tumors may be variable. We describe our experiences with unusual echographic features encountered in left and right heart myxomas. Thus the left atrial tumor may be manifested predominantly by multiple, discrete, linear echoes behind the mitral valve, the anterior leaflet of which may exhibit an abrupt mid-systolic posterior movement. In right heat myxomatous tumor arising from the septal tricupsid leaflet and adjacent interventricular septum, the echographic characteristics include a cloud of echoes throughout the cardiac cycle in the right ventricular outflow tract which are present in the right ventricle body only during relaxation and are anterior to the tricuspid valve in early diastole. Therefore, discrete linear echoes may be the principal echographic presentation of left atrial myxoma, and special attention should be focused on all areas of the tricuspid valve and right ventricle by ultrasound in patients in whom diagnosis of myxoma is suspected.     

Echocardiographic and clinical spectrum of mitral anular calcification

To establish the reliability of echocardiography in making the diagnosis of mitral anular calcification 10 consecutive patients with dense echoes at the mitral anular area were examined fluoroscopically, using an image intensifier. Nine of these had distinct mitral anular calcification. The echocardiographic reliability thus confirmed, 30 cases with similar findings were reviewed and the total group of 40 cases were used to define the echocardiographic spectrum of mitral anular calcification. This lesion extended variably from the anulus to involve the posterior left ventricular wall, mitral valve leaflets, aortic root, aortic valve and interventricular septum. The pleomorphic echocardiographic findings introduce difficulties in the diagnosis of pericardial effusion and mitral stenosis. Echocardiography is a reliable method of diagnosing mitral anular calcification, but care must be taken to avoid confusing this condition with others it resembles.     

Diagnosis of endocardial cushion defect with cross-sectional and M-mode scanning echocardiography. Differentiation from secundum atrial septal defect.

Twelve cases of endocardial cushion defect were studied before and after operation with ultrasono-cardiotomography (tomography) cross-sectional echocardiography, two-dimensional echocardiography, B-scan echocardiography) and M-mode scan along a horizontal section of the heart. For comparison, 20 healthy subjects, 18 cases of mitral valvular disease, 4 cases of congestive cardiomyopathy, 1 case of partial anomalous pulmonary venous drainage, and 25 cases of atrial septal defect of secundum type were also examined with the same technique. In cases without cardiac malformation, the echo of the anterior mitral valve was usually continuous medially with that of the interatrial septum in the horizontal plane at the level of the membranous septum. This feature was clearly recorded in all cases with right heart enlargement. In ostium secundum atrial septal defect the echo of the anterior mitral valve continued into that of the interatrial septum. An echo interruption was shown, indicating the defect itself to be in the middle part of the interatrial septum. In all the cases of endocardial cushion defect which we examined discontinuity was shown between the echo of the anterior mitral valve and that of the interatrial septum. This discontinuity was interpreted as indicating the defect itself. The mitral valve ring echo was close to the basal end of that of the interventricular septum, possibly reflecting an abnormal attachment of the mitral valve. In all cases, after operation, the echo of the artificial interatrial septum was recorded, continuous with that of the anterior mitral valve. The features of the echocardiographic sweep from the anterior mitral valve to the interatrial septum were thus different in the three groups. These echocardiographic differences are thought to correspond to the anatomical differences between the normal, atrial septal defect of secundum type, and endocardial cushion defect, and are essential features differentiating them from each other.     

Comparison of two-dimensional and M-mode echocardiography in the evaluation of patients with infective endocarditis.

M-mode and two-dimensional echocardiographic evaluation of infectious endocarditis and its complications was reviewed. In 21 consecutive patients with clinical endocarditis, 22 valves were involved (12 aortic, 5 mitral and 5 tricuspid). M-mode echocardiography detected vegetations in 10 patients (four aortic, two mitral and four tricuspid) and detected complications of endocarditis in 2 patients (one aortic root abscess and one flail aortic cusp). Two-dimensional echocardiography detected vegetations in 9 patients (four aortic, one mitral and four tricuspid) and detected complications in ten patients (five flail aortic cusps, one aortic root abscess, one sinus on Valsalva aneurysm, two flail mitral leaflets and one flail tricuspid valve). Thus, although M-mode and two-dimensional echocardiography had a similar ability to detect actual vegetations, two-dimensional echocardiography was superior to M-mode echocardiography in diagnosing complications of the destructive process.     

Spectrum of echocardiographic findings in tricuspid valve endocarditis.

This report describes a spectrum of M-mode and cross-sectional echocardiographic abnormalities in eight patients with infective endocarditis of the tricuspid valve. The M-mode echocardiogram of the tricuspid valve was abnormal in all but one patient in whom abnormal echoes were seen anterior to the tricuspid valve, in the right ventricular cavity and right ventricular outflow tract. Six patients had shaggy echoes on the tricuspid valve; and one patient showed multilayered echoes on the tricuspid valve which resembled a right atrial myxoma. Irregular diastolic fluttering of the tricuspid valve, indicative of ruptured chordae tendineae, was noted in three patients. The cross-sectional echocardiogram showed abnormal thick shaggy echoes on the tricuspid valve in all five patients on whom the procedure was performed. Contrast echocardiography confirmed the presence of tricuspid regurgitation in four patients. We conclude that echocardiography is useful in the diagnosis of tricuspid valve vegetations, and in detecting complications such as ruptured chordae tendineae and tricuspid regurgitation.     

Value of M-mode echocardiography for non-invasive diagnosis of Ebstein's anomaly.

M-mode echocardiographic studies were performed in 11 patients, most of them adults, with Ebstein's anomaly of the tricuspid valve, proven by cardiac catheterisation. Simultaneous recordings of the tricuspid and mitral valves were obtained in all cases, the transducer position being outside the left midclavicular line in seven patients. Tricuspid valve closure followed mitral valve closure in all cases, with an interval ranging between 0.04 and 0.14 s. Since, in more than 8500 routine echocardiographic studies a valve closure interval between 0.09 and 0.12 s was seen in only one patient without Ebstein's anomaly, an interval of 0.065 s or more should be regarded as diagnostic of Ebstein's disease; however, an interval shorter than 0.065 s does not exclude this diagnosis. In all patients a paradoxical septal movement was found. Two patients showed an atypical three-peaked diastolic pattern of movement of the anterior tricuspid leaflet and one patient also showed mitral valve prolapse. Pathological tricuspid valve closure delay, shown by echocardiography, makes it possible to diagnose Ebstein's anomaly in many cases without resort to cardiac catheterisation which has a relatively high risk in this disease.     

Spectrum of echocardiographic findings in tricuspid valve endocarditis

This report describes a spectrum of M-mode and cross-sectional echocardiographic abnormalities in eight patients with infective endocarditis of the tricuspid valve. The M-mode echocardiogram of the tricuspid valve was abnormal in all but one patient in whom abnormal echoes were seen anterior to the tricuspid valve, in the right ventricular cavity and right ventricular outflow tract. Six patients had shaggy echoes on the tricuspid valve; and one patient showed multilayered echoes on the tricuspid valve which resembled a right atrial myxoma. Irregular diastolic fluttering of the tricuspid valve, indicative of ruptured chordae tendineae, was noted in three patients. The cross-sectional echocardiogram showed abnormal thick shaggy echoes on the tricuspid valve in all five patients on whom the procedure was performed. Contrast echocardiography confirmed the presence of tricuspid regurgitation in four patients. We conclude that echocardiography is useful in the diagnosis of tricuspid valve vegetations, and in detecting complications such as ruptured chordae tendineae and tricuspid regurgitation.     

Echographic-quantified severity of mitral anulus calcification: Prognostic correlation to related hemodynamic,valvular, rhythm,and conduction abnormalities

Clinical and echocardiographic findings in 123 patients with mitral anulus calcification (MAC) were analyzed. In all patients M-mode echocardiography demonstrated a dense band of echoes posterior to the mitral valve, moving parallel and anterior to the left ventricular endocardium. Thirty-three per cent of patients were classified as having minimal to mild MAC (< 5 mm) and 67% had moderate to severe MAC (≥ 5 mm). There was a significant correlation between the degree of MAC to left atrial enlargement, congestive heart failure, aortic valve sclerosis, mitral regurgitation, atrial fibrillation, and AV-fascicular conduction defects. ECG evidence of conduction disturbances was significantly associated with MAC ≥ 5 mm in width. The echocardiographic demonstration of MAC ≥ 5 mm was significantly associated with the clinical implications known to occur with MAC; this echographic finding has important prognostic value in the evaluation of patients with mitral anulus calcification.     

Straddling mitral and tricuspid valves: Morphologic differences and developmental backgrounds

The anatomy of 25 hearts with a straddling mitral or tricuspid valve, or both, is described. Malalignment of atrial and ventricular septa is an essential feature of a straddling tricuspid valve, creating an inlet septal defect. Across this defect, the tricuspid valve straddles into the opposite (left ventricular) chamber, where it is separated from the mitral valve by a posterior muscular ridge, the posteromedial muscle. A straddling mitral valve requires an infundibular septal defect, predominantly of the malalignment type, in which the anterior part of the ventricular septum deviates to the left of the infundibular septum. The mitral valve straddles into the opposite (right ventricular) chamber, anterior to the trabecula septomarginalis.

From normal developmental stages, it is concluded that valve formation takes place only after completion of ventricular septation. Any malformation of the valves is therefore considered to be superimposed on a primary malformation of the septum. The ventricular septum itself develops from three different components. Malseptation in the inlet portion of the embryonic heart may lead to the characteristic septal malformation seen in straddling tricuspid valve. Malseptation in the outlet portion may lead to the septal malformation that characterizes straddling mitral valve.     

Major dehiscence of a prosthetic aortic valve: detection by echocardiography.

A 21-year-old man had acute aortic insufficiency three months after insertion of an aortic valve prosthesis. Chest roentgenography demonstrated abnormal orientation of the prosthesis. M-mode echocardiography showed dense, linear echoes from the prosthetic valve between the interventricular septum and the mitral valve, along with loss of normal poppet motion within the aortic root. At surgery, the prosthesis was found to be extensively disrupted, resulting in prolapse into the left ventricular outflow tract. Another valve replacement was performed with patient survival. Echocardiography appears to be a useful adjunct to established roentgenographic procedures in the diagnosis of major dehiscence of prosthetic aortic valves.