Echocardiographic features of atrial septal defect

Acute changes in cardiac dimensions, function, and longitudinal mechanics in healthy individuals with and without high-altitude induced pulmonary hypertension at 4559 m

BACKGROUND

High-altitude pulmonary hypertension (HAPH) has a prevalence of approximately 10%. Changes in cardiac morphology and function at high altitude, compared to a population that does not develop HAPH are scarce.

METHODS

Four hundred twenty-one subjects were screened in a hypoxic chamber inspiring a FiO2  = 12% for 2 h. In 33 subjects an exaggerated increase in systolic pulmonary artery pressure (sPAP) could be confirmed in two independent measurements. Twenty nine of these, and further 24 matched subjects without sPAP increase were examined at 4559 m by Doppler echocardiography including global longitudinal strain (GLS).

RESULTS

SPAP increase was higher in HAPH subjects (∆ = 10.2 vs. ∆ = 32.0 mm Hg, p < .001). LV eccentricity index (∆ = .15 vs. ∆ = .31, p = .009) increased more in HAPH. D-shaped LV (0 [0%] vs. 30 [93.8%], p = .00001) could be observed only in the HAPH group, and only in those with a sPAP ≥50 mm Hg. LV-EF (∆ = 4.5 vs. ∆ = 6.7%, p = .24) increased in both groups. LV-GLS (∆ = 1.2 vs. ∆ = 1.1 -%, p = .60) increased slightly. RV end-diastolic (∆ = 2.20 vs. ∆ = 2.7 cm2 , p = .36) and end-systolic area (∆ = 2.1 vs. ∆ = 2.7 cm2 , p = .39), as well as RA end-systolic area index (∆ = -.9 vs. ∆ = .3 cm2 /m2 , p = .01) increased, RV-FAC (∆ = -2.9 vs. ∆ = -4.7%, p = .43) decreased, this was more pronounced in HAPH, RV-GLS (∆ = 1.6 vs. ∆ = -.7 -%, p = .17) showed marginal changes.

CONCLUSIONS

LV and LA dimensions decrease and left ventricular function increases at high-altitude in subjects with and without HAPH. RV and RA dimensions increase, and RV longitudinal strain increases or remains unchanged in subjects with HAPH. Changes are negligible in those without HAPH.

Consanguinity and isolated atrial septal defect in North East of Iran

BACKGROUND AND OBJECTIVES

The rate of consanguineous marriage is high in Middle Eastern countries such as Iran. The relationship between consanguineous marriage and congenital heart disease is discussed in some studies, but there is not much data for relationship between atrial septal defect (ASD) and consanguineous marriage. The aim of this study was to evaluate the relationship between consanguineous marriage and ASD echocardiographic characteristics.

DESIGN AND SETTINGS

This was a cross-sectional study approved by Mashhad University of Medical Sciences ethics committee and took place in Mashhad, Iran, for a period of 3 years from August 2008 till September 2011.

METHODS

In this cross-sectional study, 113 ASD patients participated and they were categorized into 3 groups on the basis of family relationship between their parents: first group-"no relationship," second group- "third degree relationship," and third group- "far relationship."

RESULTS

Among the 54 male and 59 female ASD patients, the most prevalent type of ASD was ASD secundum (85.0%) followed by sinus venosus (8.8%). A total of 56% patients were present in the first group and 15% and 29% in the second group and the third group, respectively." The relationship between consanguinity and type of ASD (P < .001) and gender (P < .001 each) was observed. The relationship between the age of onset of disease and consanguinity (P=.003) was also observed.

CONCLUSION

Considering the fact that there is a high prevalence of ASD and consanguineous marriage in Iran and bearing in mind the results of the present study, we recommend educating couples about the outcomes of consanguineous marriage in pre-marriage counseling.

A critical review of patent foramen ovale detection using saline contrast echocardiography: when bubbles lie

Saline and indocyanine green dye were the first agents noted to produce a contrast effect when injected peripherally during M-mode echocardiographic imaging, although it was subsequently found that almost any type of injected solution would have this effect. These first-generation contrast agents were limited to opacification of right heart structures, and they prompted subsequent development of agents that traverse pulmonary circulation. Although opacification limited to right heart structures is considered a limitation of these first-generation agents, this is an advantage when attempting to identify the presence of right-to-left shunt. First-generation air contrast is considered the gold standard for identification of patent foramen ovale (PFO). However, PFO investigators have used varying criteria to define abnormal contrast studies. There are also multiple mechanisms by which saline contrast studies may produce both false-positive and false-negative results for presence of PFO. There is mounting experimental evidence that PFO is associated with cerebral ischemia and migraine headache, with a resulting evolution of devices for percutaneous closure of these shunts. Echocardiographic physicians must be aware of potential pitfalls of the air contrast technique to avoid exposing patients to unnecessary risk of closure devices, and missing the potential benefit of shunt closure in appropriately selected patients.

The history of echocardiography

Following a brief review of the development of medical ultrasonics from the mid-1930s to the mid-1950s, the collaboration between Edler and Hertz that began in Lund in 1953 is described. Using an industrial ultrasonic flaw detector, they obtained time-varying echoes transcutaneously from within the heart. The first clinical applications of M-mode echocardiography were concerned with the assessment of the mitral valve from the shapes of the corresponding waveforms. Subsequently, the various M-mode recordings were related to their anatomical origins. The method then became established as a diagnostic tool and was taken up by investigators outside Lund, initially in China, Germany, Japan and the USA and, subsequently, world-wide. The diffusion of echocardiography into clinical practice depended on the timely commercial availability of suitable equipment. The discovery of contrast echocardiography in the late 1960s further validated the technique and extended the range of applications. Two-dimensional echocardiography was first demonstrated in the late 1950s, with real-time mechanical systems and, in the early 1960s, with intracardiac probes. Transesophageal echocardiography followed, in the late 1960s. Stop-action two-dimensional echocardiography enjoyed a brief vogue in the early 1970s. It was, however, the demonstration by Bom in Rotterdam of real-time two-dimensional echocardiography using a linear transducer array that revolutionized and popularized the subject. Then, the phased array sector scanner, which had been demonstrated in the late 1960s by Somer in Utrecht, was applied to cardiac studies from the mid-1970s onwards. Satomura had demonstrated the use of the ultrasonic Doppler effect to detect tissue motion in Osaka in the mid-1950s and the technique was soon afterwards applied in the heart, often in combination with M-mode recording. The development of the pulsed Doppler method in the late 1960s opened up new opportunities for clinical innovation. The review ends with a mention of color Doppler echocardiography. (E-mail:

Assessment of regional myocardial strain by a novel automated tracking system from digital image files

Myocardial strain imaging by Doppler tissue echocardiography is a useful method to quantify regional left ventricular function. However, this method has a problem of its Doppler angle dependency. We attempted to quantify myocardial strain by a newly developed automated tracking system from digital image files. In 6 anesthetized open-chest dogs, a pair of ultrasonic crystals was implanted at the inner site and outer site of the left ventricular wall to measure myocardial radial strain. B-mode echocardiographic images and trajectories of crystals were recorded simultaneously. Three conditions were examined by intravenous infusion of dobutamine. We used a pattern matching algorithm, which allowed us to track objects from one frame to the next. In 18 image sequences obtained in the 6 dogs, there was an excellent correlation in maximal myocardial strain between the two methods ( r = 0.92, P < .0001). Thus, this system is a promising tool to provide automated quantification of regional myocardial strain.

Evaluation of abnormal motion of interventricular septum after coronary artery bypass grafting operation: assessment by ultrasonic strain rate imaging

We investigated whether strain rate imaging by echocardiography can quantify abnormal motion of interventricular septum (IVS) after coronary artery bypass grafting operation (CABG). Strain rate imaging was performed in 12 patients with angina pectoris treated by CABG; 12 patients with angina pectoris treated medically, with catheter intervention, or both (non-CABG); and 10 patients with previous anterior myocardial infarction. Peak systolic Doppler tissue velocity of mid-IVS was significantly lower in the CABG group than in the non-CABG group (2.15 +/- 0.58 cm/s vs 3.37 +/- 1.15 cm/s; P <.05). However, there was no significant difference in peak systolic strain (PSS) rate and PSS of mid-IVS between CABG and non-CABG groups. PSS rate and PSS of mid-IVS were significantly lower in the anterior myocardial infarction group than in the non-CABG group (-0.45 +/- 0.25/s vs -1.22 +/- 0.28/s and -5.8 +/- 4.9% vs -17.2 +/- 3.4%, respectively; P <.0001). Strain rate imaging can quantify accurate left ventricular function in cases of apparently reduced cardiac motion.

Ventricular septal flattening at end systole falsely predicts right ventricular hypertension in patients with ostium primum atrial septal defects

PURPOSE

To assess the reliability of ventricular septal position in predicting elevated right ventricular pressure (RVP) in patients with ostium primum atrial septal defects (ASD 1).

METHODS

Echocardiograms of 4 groups were retrospectively analyzed: Patients with ASD 1 and low RVP, patients with ASD 1 and high RVP, and 2 age-matched control groups: one with isolated ostium secundum atrial septal defects (ASD 2), and 1 with normal cardiac findings. End-systolic left ventricular sectional diameters along the midmitral diameter (D1) and a diameter orthogonal to it (D2) were measured off-line by a blinded observer. The ratio D2/D1, the eccentricity index (EI), was calculated; a higher index represents greater septal flattening.

RESULTS

The mean EI in the ASD 1 with low RVP group was significantly higher than both the group with ASD 2 and the healthy control group. The mean EI of the ASD 1 group with high RVP was significantly higher than the mean EI of the ASD 1 group with low RVP, although there was a poor correlation between EI and RVP in this group, r = 0.54.

CONCLUSION

The ventricular septum is flatter in the ASD 1 patients with low RVP than in an age-matched control group with ASD 2 and compared with an age-matched control group of healthy subjects, giving a false impression of elevated RVP in the ASD 1 group. Although the mean EI is significantly higher in the ASD 1 group with high RVP than in the group with low RVP, there is a poor correlation between EI and RVP, which limits the reliability of this index.

Compression of interventricular septum during right ventricular pressure loading

The interventricular septum, which flattens and inverts in conditions such as pulmonary hypertension, is considered by many to be an unstressed membrane, in that its position is assumed to be determined solely by the transseptal pressure gradient. A two-dimensional finite element model was developed to investigate whether compression and bending moments (behavior incompatible with a membrane) exist in the septum during diastole under abnormal loading, i.e., pulmonary artery (PA) constriction. Hemodynamic and echocardiographic data were obtained in six open-chest anesthetized dogs. For both control and PA constriction, the measured left ventricular and right ventricular pressures were applied to a residually stressed mesh. Adjustments were made to the stiffness and end-bending moments until the deformed and loaded residually stressed mesh matched the observed configuration of the septum. During PA constriction, end-bending moments were required to obtain satisfactory matches but not during control. Furthermore, substantial circumferential compressive stresses developed during PA constriction. Such stresses might impede septal blood flow and provoke the unexplained ischemia observed in some conditions characterized by abnormal septal motion.

Quantitative assessment of regional right ventricular function with color kinesis

We used color kinesis, a recent echocardiographic technique that provides regional information on the magnitude and timing of endocardial wall motion, to quantitatively assess regional right ventricular (RV) systolic and diastolic properties in 76 subjects who were divided into five groups, as follows: normal (n = 20), heart failure (n = 15), pressure/volume overload (n = 14), pressure overload (n = 12), and RV hypertrophy (n = 15). Quantitative segmental analysis of color kinesis images was used to obtain regional fractional area change (RFAC), which was displayed in the form of stacked histograms to determine patterns of endocardial wall motion. Time curves of integrated RFAC were used to objectively identify asynchrony of diastolic endocardial motion. When compared with normal subjects, patients with pressure overload or heart failure exhibited significantly decreased endocardial motion along the RV free wall. In the presence of mixed pressure/volume overload, the markedly increased ventricular septal motion compensated for decreased RV free wall motion. Diastolic endocardial wall motion was delayed in 17 of 72 segments (24%) in patients with RV pressure overload, and in 31 of 90 segments (34%) in patients with RV hypertrophy. Asynchrony of diastolic endocardial wall motion was greater in the latter group than in normal subjects (16% versus 10%: p < 0.01). Segmental analysis of color kinesis images allows quantitative assessment of regional RV systolic and diastolic properties.

Echocardiographic Detection of Occult Cor Pulmonale During Exercise in Patients with Chronic Obstructive Pulmonary Disease

We tested the ability of cycle ergometer exercise echocardiography to detect cases of occult cor pulmonale among 25 patients with chronic obstructive pulmonary disease (COPD). The M-mode echocardiographic ventricular septal motion, left ventricular shape determined by short-axis two-dimensional (2-D) echocardiography, and right and left ventricular pressure curves were recorded at rest and during exercise and were compared between patients. The ventricular septal motion was normal at rest in all of the patients. In nine patients (dip group), there was marked downward ventricular septal motion in early diastole during exercise, indicating distortion of the left ventricular shape. There were no distinct changes in the remaining 16 patients (non-dip group). At rest, the cardiac index was significantly lower, and right ventricular systolic and mean pulmonary artery pressures were significantly higher in the dip group than in the non-dip group. However, no significant difference was noted in the right ventricular end-diastolic pressure between the two groups at rest. The right ventricular systolic and end-diastolic pressures were greater during exercise in the dip group than in the non-dip group. In all of the patients in the dip group, the right ventricular pressure exceeded the left ventricular pressure only in early diastole, coinciding with the early diastolic dip of the ventricular septum, during exercise. In conclusion, occult cor pulmonale can be diagnosed accurately by the appearance of an early diastolic dip of the ventricular septum and distorted left ventricular shape during exercise in patients with COPD.

Analysis of ventricular septal motion by doppler tissue imaging in atrial septal defect and normal heart

The aortic root and the upper part of the ventricular septum moves anteriorly in early systole, while the lower part moves posteriorly. The hinge of the counterpart motion of the ventricular septum is called pivot point. Using Doppler tissue imaging (DTI), we attempted to clarify the location of the pivot point of the ventricular septum in children with normal heart and with atrial septal defect (ASD), and to investigate the relation between the degree of the downward shift of the pivot point and that of volume overload of the right ventricle in patients with ASD. Study subjects consisted of 20 healthy children and 36 patients with ASD, aged from 1 to 15 years (mean 5.7+/-3.4) in the normal group and 6 months to 12 years (mean 4.4+/-3.2) in the ASD group, respectively. The pivot point was designated as a border of the color signal of DTI of the ventricular septum in early systole. Measurements were then obtained on cross-sectional echocardiography and DTI: septal length in the parasternal long-axis view, distance from aortic valve to pivot point in early systole, diastolic left ventricular internal dimension, and diastolic right ventricular internal dimension. In the normal group, the ratio of distance from aortic valve to pivot point/septal length was 0.13+/-0.049, whereas it was 0.26+/-0.168 in the group with ASD (p <0.001). In the ASD group, the distance from aortic valve to pivot point normalized by body surface area (mm/m2) correlated with the ratio of diastolic right/left ventricular internal dimension and with the ratio of pulmonary to systemic flow (Qp/Qs) (r = 0.63 and 0.50, respectively). The ratio of the distance from aortic valve to pivot point/septal length correlated with the ratio of diastolic right/left ventricular internal dimension and Qp/Qs (r = 0.56 and 0.44, respectively). By DTI, the pivot point was located at the upper 13+/-5% of the total length of the ventricular septum in normal children, and was located at 26+/-17% in patients with ASD (p < 0.001). The degree of this displacement in ASD correlated with that of volume overload of the right ventricle. The paradoxic motion of the ventricular septum shown in the ASD could be explained by this downward shift of the pivot point.

Comparative usefulness of myocardial velocity gradient in detecting ischemic myocardium by a dobutamine challenge

OBJECTIVES

We tested the hypothesis that ischemic myocardium can be sensitively detected using tissue Doppler-derived myocardial velocity gradient (MVG) by a dobutamine challenge.

BACKGROUND

Although tissue Doppler imaging (TDI) has recently emerged to quantify regional myocardial contraction, increased translational motion during a dobutamine challenge may affect the measurements. MVG is an indicator of regional myocardial contraction independent of the translational motion.

METHODS

We studied 19 patients with (n = 13) and without (n = 6) confirmed single-vessel coronary artery disease. Left ventricular short-axis tissue Doppler images were obtained along with conventional echocardiograms during a submaximal two-step dobutamine challenge (10 and 30 microg/kg body weight per min). Endocardial velocity as well as MVG were derived from TDI using computer analysis in the anteroseptal and posterior segments and were compared with visual interpretation.

RESULTS

MVG demonstrated a significant dose-responsive increase in the nonischemic segments (anteroseptal: 2.6 +/- 0.8/s to 6.0 +/- 1.0/s [mean +/- SD], p < 0.05; posterior: 3.9 +/- 0.7/s to 7.6 +/- 1.8/s, p < 0.05) but remained unchanged in the ischemic segments (anteroseptal: 2.5 +/- 0.8/s to 2.7 +/- 0.7/s, p = NS; posterior: 3.4 +/- 1.0/s to 4.1 +/- 0.9/s, p = NS). Endocardial velocity failed to clearly demonstrate the differing responses between the nonischemic (anteroseptal: -2.3 +/- 1.2 to -2.7 +/- 1.6 cm/s, p = NS; posterior: 3.8 +/- 1.1 to 73 +/- 2.7 cm/s, p < 0.05) and ischemic segments (anteroseptal: -2.1 +/- 0.5 to -2.8 +/- 0.8 cm/s, p = NS; posterior: 4.2 +/- 0.8 to 6.5 +/- 2.6 cm/s, p = NS). Wall motion abnormality was hardly detectable with visual interpretation (wall motion score range 1.00 to 1.33).

CONCLUSIONS

Abnormal segments could be sensitively detected by using MVG in a submaximal dobutamine challenge, even where conventional methods failed to detect the abnormality.

Cross sectional echocardiographic demonstration of the mechanisms of abnormal interventricular septal motion in congenital total absence of the left pericardium

OBJECTIVE

To investigate the influence of the absence of the pericardium on the left ventricular wall, particularly on interventricular septal motion, using M mode and cross sectional short axis echocardiography in patients with congenital total absence of the left pericardium.

METHODS

21 patients with, congenital total absence of the left pericardium were divided into three groups according to the interventricular septal motion; systolic type (n = 6) with paradoxical motion during systole, diastolic type (n = 11) with abnormal posterior motion during mid to late diastole, and mixed type (n = 4) with paradoxical motion during systole and abnormal posterior motion during diastole.

RESULTS

On cross sectional short axis echocardiograms of the left ventricle, in the diastolic type the degree of angular displacement of the papillary muscles during end diastole to end systole showed excessive anticlockwise rotation about the long axis of the left ventricle without marked anteroposterior displacement. In the systolic type, there was shift of the left ventricle towards the anteromedial portion in systole and towards the posterolateral portion in diastole without significant rotation. There was a significantly positive correlation between the degree of angular displacement and the amplitude of diastolic interventricular septal motion during mid to late diastole in all patients.

CONCLUSIONS

There was abnormal interventricular septal motion during systole and diastole in patients with total absence of the left pericardium. Abnormal systolic motion was induced by anteroposterior displacement of the left ventricle, and abnormal diastolic motion by left ventricular rotation about the long axis of the heart during the cardiac cycle. Analysis using cross sectional echocardiography was useful for elucidating the mechanisms of abnormal interventricular septal motion.

Usefulness of myocardial velocity gradient derived from two-dimensional tissue Doppler imaging as an indicator of regional myocardial contraction independent of translational motion assessed in atrial septal defect

Independence of myocardial velocity gradient from translational motion of the heart was tested by comparing normal subjects and patients with atrial septal defect. Myocardial velocity gradient obtained from patients fit within the normal range, even though the translation of the left ventricle was exaggerated in patients, demonstrating the translation independence of myocardial velocity gradient in clinical settings.

Three-dimensional ultrasound imaging of the atrial septum: normal and pathologic anatomy

OBJECTIVES

This study investigated the feasibility of producing three-dimensional gray scale ultrasound images of the atrial septum to demonstrate normal and pathologic anatomy.

BACKGROUND

Two-dimensional echocardiography is the principal technique used for imaging the atrial septum. Although the diagnostic accuracy of two-dimensional echocardiography is high, its capability for displaying complex three-dimensional relations is limited.

METHODS

Three-dimensional ultrasound images were reconstructed from tomographic images obtained during routine transesophageal echocardiographic examinations. Custom-made semi-automatic algorithms for image enhancement, interpolation and segmentation were used to produce volumetric gray scale images. Volume-rendered displays of the atrial septum were generated for analysis. Sequential three-dimensional images were generated through the cardiac cycle and displayed cinematographically to permit assessment of motion.

RESULTS

The three-dimensional images obtained from six patients clearly demonstrated normal and pathologic anatomy of the atrial septum, including atrial septal defects, atrial septal aneurysm and aortic valve ring abscess. The images could be manipulated electronically to demonstrate spatial relations and internal structural details.

CONCLUSIONS

Three-dimensional gray scale reconstruction of ultrasound images obtained by transesophageal echocardiography is feasible. These images clearly demonstrate anatomic details and spatial relations. The gray scale images may be interactively manipulated to optimize the clinician's visualization of the atrial septum and its associated pathologic conditions.

Echocardiographic assessment of atrial septal defects

Echocardiography has become the method of choice for the assessment of patients with a known or suspected atrial septal defect. The majority of patients with defects can be identified by this method. In patients with inconclusive transthoracic studies, transesophageal echocardiography is useful for identification or exclusion of a defect. Echocardiography is useful for quantification of left-to-right shunting, identification of associated anomalies, and estimation of pulmonary pressure. Cardiac catheterization can be reserved for patients who require measurement of pulmonary vascular resistance, those who have a significant risk of coronary artery disease, and those with complex congenital heart disease.

Relationship between septal perfusion, viability, and motion before and after coronary artery bypass surgery

The etiology of abnormal interventricular septal motion occurring after open-heart surgery using cardiopulmonary bypass has not been clarified. Intraoperative ischemic septal injury has been proposed as one explanation for this finding. To examine this possibility, resting septal perfusion and viability were studied using rest and redistribution thallium-201 scintigraphy in 16 patients before and after coronary artery bypass surgery. The results were compared with septal motion on preoperative and postoperative resting gated blood pool scans. Preoperatively, septal thallium uptake was normal in 10 of 16 patients, and septal motion was normal in 14 of 16. Postoperatively, septal thallium uptake was normal in 11 of 16 patients, while septal motion was abnormal in all. Thus abnormal postoperative septal motion is usually associated with normal septal perfusion and viability on thallium scans and therefore is not the result of septal ischemic injury in a majority of patients.

Sensitivity of contrast ultrasound in the detection of atrial septal defect with predominant left-to-right shunting

Ultrasound contrast techniques are used widely as a screening test for intracardiac shunt. We performed a retrospective analysis of contrast echocardiograms in 29 consecutive patients with atrial septal defect (excluding Eisenmenger's) proved by cardiac catheterization. A positive (right-to-left atrial) ultrasound contrast effect was seen in 25 patients in whom catheterization pulmonary-to-systemic flow rate (Qp/Qs) was 2.2 +/- 0.9 (SD). Four patients had false-negative contrast echocardiography results; their Qp/Qs was 2.9 +/- 0.4 (p = 0.07). The percent left-to-right shunt was higher in the group with false-negative contrast echocardiographic results (65% +/- 4% vs 47% +/- 21%) (p = 0.05). Shunts with Qp/Qs < or = 2.0 had a sensitivity of 100%, whereas those with Qp/Qs > or = 2.1 had a sensitivity of 73%. In the four false-negative contrast echocardiographic results, three had findings of an atrial septal defect by pulsed Doppler, color Doppler, or both. Thus the presence of a large left-to-right shunt may decrease the sensitivity of the ultrasound contrast technique for the detection of an atrial septal defect. Contrast ultrasonography should be used in conjunction with Doppler and two-dimensional echocardiography criteria for diagnosis of atrial septal defect.

Transient abnormal septal motion after non-surgical closure of the ductus arteriosus

Abnormal septal motion on M mode echocardiography was seen in eight of 16 patients soon after non-surgical closure of the ductus arteriosus. Ten to twenty-nine months after the procedure the abnormal septal motion had disappeared spontaneously. The cross section of the left ventricular cavity was circular both when septal motion was abnormal and when it was normal. Cross sectional echocardiography showed that there was an exaggerated anterior swinging motion of the heart in systole in patients with abnormal septal motion on the M mode recordings. The left ventricular end diastolic diameter before closure was significantly larger, and its reduction after closure was more pronounced in those with abnormal septal motion than in those without. This suggested that the abnormal septal motion was associated with relief of long standing left ventricular volume overload. It is suggested that acute shrinkage of the heart caused temporary laxity of the pericardium, and consequently more movement of the heart within the thorax. The return of normal septal motion suggests that the pericardium gradually shrank to accommodate the smaller heart.

Doppler atrial shunt flow patterns in patients with secundum atrial septal defect: determinants, limitations, and pitfalls

Fifteen patients with uncomplicated secundum atrial septal defect underwent studies with real-time color-coded two dimensional flow imaging, pulsed Doppler echocardiographic examination, and simultaneous pressure recordings from the left and right atrium to determine the flow-pressure dynamics of the atrial shunt flow. In all 15 patients both the color flow mapping and pulsed Doppler studies revealed that the shunt flow was mainly from left to right, occurring both during ventricular systole and diastole. It started in early systole, reached a peak in late systole to early diastole, and lasted throughout diastole with an accentuation in late diastole during atrial contraction. The amplitude of the flow velocity, the direction, and the magnitude of the shunt flow, however, changed from phase to phase during the cardiac cycle. It correlated well with the phasic variation of the interatrial pressure difference, which usually revealed a peak pressure gradient that occurred in early systole between the x descent and v wave and during the period of v wave and a wave of the left atrial pressure tracing. Right to left shunt was not detected in any of the 15 patients by color flow mapping studies. A minor reversal of the shunt flow, however, was frequently detected at the beginning of ventricular systole and sometimes also in the middle of diastole by pulsed Doppler echocardiography. The reversal of shunt flow correlated with the minor reversal of pressure gradient that occurred during the z point, x descent, and y descent of the left atrial pressure tracing. In conclusion, left to right shunt flow occurs both during ventricular systole and diastole in uncomplicated secundum atrial septal defect.(ABSTRACT TRUNCATED AT 250 WORDS)

Interventricular septal motion and left ventricular function in patients with atrial septal defect

In order to assess whether the paradoxical motion of the interventricular septum seen in patients with atrial septal defect (ASD) is due to a true abnormality in septal contraction, eight patients with ASD (age, 1.6-17 years) and eight age-matched control patients were studied using qualitative and quantitative two-dimensional (2D) and M-mode echocardiography. 2-D-echocardiographic images recorded from the parasternal short-axis projection at the level of the papillary muscles and 2D-directed M-mode tracings at this level were obtained. Comprehensive wall motion analysis of the left ventricular (LV) endocardial and epicardial borders was performed using both fixed reference and center of mass (floating reference) models. Our results indicate that interventricular septal wall motion and function are normal in patients with ASD. The apparent "paradoxical" motion is due to excessive anterior motion of the entire left ventricle, and is present only when a fixed reference system is used to assess myocardial motion, but is not present when a center of mass (floating reference system) is employed. Left ventricular function assessed by % area and perimeter change, mean radial shortening fraction, and mean radial wall thickening (2D) as well as LV shortening fraction and septal and posterior wall thickening (M-mode) was not significantly different between the two groups. Standard M-mode tracings can therefore be used to assess LV function despite this apparent abnormal septal motion.

Transseptal pressure gradient and diastolic ventricular septal motion in patients with mitral stenosis

Previous studies from our laboratory have shown that the position of the ventricular septum relative to the two ventricles at end-diastole is determined by the instantaneous transseptal pressure gradient (TSG) defined as left ventricular minus simultaneous right ventricular pressure. Since patients with mitral stenosis often have exaggerated leftward (paradoxic) motion of the ventricular septum during early diastole, we studied seven patients with mitral stenosis undergoing cardiac catheterization to determine if position (and therefore motion) of the ventricular septum was determined by TSG throughout diastole. M Mode echocardiograms derived from a two-dimensional parasternal short-axis view were recorded with simultaneous micromanometer measurements of left ventricular and right ventricular pressures. Six of seven patients demonstrated abnormal early diastolic leftward motion of the ventricular septum in at least one cardiac cycle. TSG measured at intervals throughout diastole ranged from -2.5 to +20 mm Hg, with abnormal TSG observed in most of the 40 cardiac cycles selected for analysis. The intracardiac position of the ventricular septum, defined as the distance from the right ventricular epicardium (RVEpi) to the left surface of the ventricular septum normalized for total cardiac dimension (RVEpi-VS), was plotted against left ventricular pressure, right ventricular pressure, and TSG. Linear regression of pooled data from all patients (164 observations) demonstrated a highly significant correlation between the instantaneous TSG and the relative intracardiac position of the ventricular septum (RVEpi-VS = 1.52 TSG + 42.7; r = .79, p less than .0001).(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of chronic pulmonary hypertension on left ventricular size, function, and interventricular septal motion

The effect of right ventricular pressure overload secondary to chronic pulmonary arterial hypertension on left ventricular size and function and on interventricular septal motion was studied in 13 patients in whom coronary artery disease, hypertension, and hypoxemia were excluded. Regional and global left ventricular function were assessed by computer-assisted analysis of two-dimensional directed M-mode echocardiograms obtained within 24 hours of a hemodynamic study. Septal position and motion were further analyzed by delineating seven points along the right and left sides of the septum during a single cardiac cycle. All echocardiographic data were compared to those of 10 normal subjects. Mean values for right ventricular systolic, mean pulmonary artery and pulmonary capillary wedge pressures were: 71 +/- 26 mm Hg, 46 +/- 16 mm Hg, and 7 +/- 1 mm Hg, respectively. Septal motion was interpreted from the M-mode echocardiograms as normal in seven patients (group I) and abnormal in the remaining six patients (group II). The only hemodynamic parameter which distinguished these two patterns was delta P, the transseptal systolic pressure gradient across the interventricular septum, which was significantly different (p less than 0.02) in group I (delta P = 65 +/- 16 mm Hg) from that of group II (delta P = 21 +/- 24 mm Hg). As a result of abnormal septal position, the septal-free wall dimensions of the left ventricle were reduced, but there was no evidence of depressed left ventricular performance in these patients. We conclude that resting left ventricular function is well preserved in patients with pulmonary hypertension, despite significant alterations in septal position and left ventricular size.(ABSTRACT TRUNCATED AT 250 WORDS)

Contrast echocardiography in the evaluation of interatrial septal defect

One hundred twenty-four adult patients consecutively referred for suspected interatrial septal defect (IASD) were studied with contrast echocardiography. In 58 the study eliminated altogether the diagnosis of any significant cardiac defect. Fifteen patients had other forms of cardiac abnormalities with no shunting of blood, and 51 patients had echocontrast study positive for interatrial shunting; 48 of these were subsequently proven by cardiac catheterization to have IASD. Echocontrast provided a highly sensitive and specific means of both diagnosing IASD and eliminating this diagnosis.

Value of respiratory variations of right ventricular dimension in the identification of small atrial septal defects (secundum type) not requiring surgery: an echocardiographic study

In search of reliable criteria that could help differentiate insignificant atrial septal defects (ASDs) from those with a large shunt, M-mode echocardiograms of three groups of patients were studied retrospectively: group I = 10 normal children (mean age 5.7 years); group II = 10 patients (mean age 7 years) with small ASD in whom the decision was taken not to proceed to surgical closure, based on hemodynamic and angiographic criteria; and group III = 15 patients (mean age 7 years) with an "operable" shunt, who underwent corrective surgery. The results showed that right ventricular end-diastolic dimensions during expiration (RVDDE) were increased in all patients in group III but were normal in only 3 of the 10 patients in group II. A normal septal movement was found in all patients in groups I and II but also in five patients in group III. The variation in right ventricular diastolic dimension with respiration (RVDVR) was always normal in group II. However, in group III all patients but one had a small RVDVR (less than 6%). It was concluded that a normal RVDDE is very specific (100%) but not sensitive (30%), a normal septal movement is very sensitive (100%) and moderately specific (70.6%), and a normal RVDVR is both very sensitive (100%) and specific (94.4%) as a criterion for identification of small ASDs not requiring surgery.

Paradoxical and pseudoparadoxical interventricular septal motion in patients with right ventricular volume overload

Cross-sectional echocardiographic measurements of normalized septal curvature (NSC), systolic anterior motion of the center of the left ventricular cavity (CAM), and the M mode ratio of left ventricular posterior wall epicardial motion (PEM) to posterior wall thickening (PWT) were made in eight normal subjects, 16 patients with right ventricular volume overload (RVVO) and five with pressure overload (RVPO). Paradoxical M mode septal motion was confined to early systole in six patients with RVVO (group I) and was sustained in 10 (group II). Similar end-diastolic septal flattening was observed in RVVO group I (NSC 0.50 +/- 0.16 [SD]) and group II (0.49 +/- 0.23) when compared with the normal group (0.83 +/- 0.07, both p less than .005). NSC increased in both RVVO groups during the first one-third of systole (p less than .002) to values not significantly different from normal, but did not change significantly thereafter. CAM in RVVO group II (5.4 +/- 2.2 mm) exceeded CAM in both the normal group (1.8 +/- 1.9 mm, p less than .001) and group I (2.1 +/- 1.4 mm, p less than .005). Similarly, the PEM/PWT ratios in group II (mean 2.94; range 2.13 to 8.0) exceeded those in both the normal group (mean 1.59; range 1.11 to 2.13, p less than .01) and group I (mean 1.32; range 1.10 to 1.67, p less than .01). In the RVPO group, CAM was significant, the PEM/PWT ratios were lower than normal (p less than .01), and marked end-diastolic septal flattening was incompletely corrected during early systole, after which the septum was flattened further until end-systole (p less than .005).(ABSTRACT TRUNCATED AT 250 WORDS)

Paradoxical ventricular septal motion with right ventricular dilatation as a manifestation of pure pressure overload due to pulmonary veno-occlusive disease

Paradoxical interventricular septal motion with right ventricular dilatation has been considered the hallmark of right ventricular volume overload. We report a 43-year-old woman with severe pulmonary hypertension due to pulmonary veno-occlusive disease who exhibited these echocardiographic abnormalities. Right ventricular volume overload was excluded by physical examination, echocardiography with saline contrast study and by cardiac catheterization, angiography, and shunt study. These echocardiographic findings are thus not pathognomonic of right ventricular volume overload and can be seen with pressure overload as well.

Two-dimensional echocardiographic determinants of interventricular septal configurations in right or left ventricular overload

Configurations of interventricular septum (IVS) and left ventricle were evaluated in 60 normal subjects and in 68 patients with congenital heart disease using two-dimensional short axis cross-sectional echocardiography (2DE). Patients were divided into four groups; right ventricular (RV) pressure overload (n = 21), RV volume overload (n = 12), left ventricular (LV) pressure overload (n = 10), and LV volume overload (n = 25). The radii of curvature of the IVS (IVSr) and LV free wall (FWr) were calculated in end systole and end diastole. Measured IVSr was normalized by dividing IVSr by FWr (IVSr/FWr). End-systolic flattening of IVS was a specific finding in patients with RV pressure overload, since this pattern was not observed in other hemodynamic groups. Echocardiographic determinants of IVSr/FWr in end systole correlated well with RV peak systolic pressure/LV peak systolic pressure ratio (r = 0.878). There was also correlation between IVSr/FWr in end diastole and RV end-diastolic pressure/LV end-diastolic pressure ratio (r = 0.579). Thus, the evaluation of IVS configuration is a useful 2DE method of estimating relative RV systolic pressure in infants and children with congenital heart disease.

Usefulness of echocardiographic assessment of right ventricular and pulmonary trunk size for estimating magnitude of left-to-right shunt in children with atrial septal defect

M-mode and 2-dimensional echocardiographic studies were performed in 42 patients, aged 1 to 16 years (mean 6), with a secundum or sinus venosus type atrial septal defect (ASD) and normal pulmonary artery pressure. Twenty normal children served as a control group. In patients with ASD the echocardiographic variables were correlated with the magnitude of the left-to-right shunt (Qp/Qs) calculated by the Fick principle. Although M-mode echocardiograms showed increased right ventricular (RV) dimension in 69% of the patients, the correlation between RV dimension index (RV dimension/body surface area) and Qp/Qs was weak (r = 0.49). When RV dimension was related to left ventricular (LV) dimension and expressed by the RV/LV ratio, 90% of the patients were found to have an abnormally large right ventricle. The correlation between the RV/LV ratio and Qp/Qs was fairly good (r = 0.64). In 33 patients (78%), the pulmonary trunk (PT) was adequately visualized and measured on 2-dimensional echocardiograms. The dimension of the PT was related to the aortic root dimension and expressed by the PT dimension/aortic dimension ratio. This ratio was 0.99 +/- 0.06 in normal children and 1.35 +/- 0.23 in patients with ASD (p less than 0.001). The PT/aortic ratio exceeded the upper limit of normal (the normal mean value + 2 standard deviations) in each of the 27 patients with a Qp/Qs of 1.5 or greater. In 5 of the 6 patients with a Qp/Qs of less than 1.5 the PT/aortic ratio was close to 1 and within the normal range. An excellent correlation (r = 0.89) was found between the PT/aortic ratio and Qp/Qs.(ABSTRACT TRUNCATED AT 250 WORDS)

An echocardiographic index for separation of right ventricular volume and pressure overload

Abnormal motion of the interventricular septum has been described as an echocardiographic feature of both right ventricular volume and pressure overload. To determine if two-dimensional echocardiography can separate these two entities and distinguish them from normal, geometry and motion of the interventricular septum in short-axis views of the left ventricle were evaluated in 12 normal subjects and 35 patients undergoing cardiac catheterization. Thirteen of the 35 patients had uncomplicated atrial septal defect with associated right ventricular volume overload, but no elevation in pulmonary artery pressure. The 22 remaining patients had a pulmonary artery systolic pressure greater than 40 mm Hg and, thus, constituted the group with right ventricular pressure overload. An eccentricity index, defined as the ratio of the length of two perpendicular minor-axis diameters, one of which bisected and was perpendicular to the interventricular septum, was obtained at end-systole and end-diastole. In all normal subjects, the eccentricity index at both end-systole and end-diastole was essentially 1.0, as would be expected if the left ventricular cavity was circular in the short-axis view. In patients with right ventricular volume overload, the eccentricity index was approximately 1.0 at end-systole, but was significantly increased at end-diastole (mean eccentricity index = 1.26 +/- 0.12) (p less than 0.001). In patients with right ventricular pressure overload, the eccentricity index was significantly greater than 1.0 at both end-systole and end-diastole (1.44 +/- 0.16 and 1.26 +/- 0.11, respectively) (p less than 0.001). These results suggest that an index of eccentric left ventricular shape which reflects abnormal motion of the interventricular septum can be defined.(ABSTRACT TRUNCATED AT 250 WORDS)

Is routine preoperative cardiac catheterization necessary before repair of secundum and sinus venosus atrial septal defects?

Between January 1976 and July 1983, 217 patients with atrial septal defect underwent surgical repair at Children's Hospital. Thirty with a primum atrial septal defect and 26 who underwent cardiac catheterization elsewhere before being seen were excluded from analysis. Of the 161 remaining patients, 52 (31%) underwent preoperative cardiac catheterization, 38 because the physical examination was considered atypical for a secundum atrial septal defect and 14 because of a preexisting routine indication. One hundred nine (69%) underwent surgery without catheterization, with the attending cardiologist relying on clinical examination alone in 5, additional technetium radionuclide angiocardiography in 5, M-mode echocardiography in 13 and two-dimensional echocardiography in 43; both M-mode echocardiography and radionuclide angiography were performed in 24 and two-dimensional echocardiography and radionuclide angiography in 19. Since 1976, there has been a trend toward a reduction in the use of catheterization and use of one rather than two noninvasive or semiinvasive techniques for the detection of atrial defects. Of the 52 patients who underwent catheterization, the correct anatomic diagnosis was made before catheterization in 47 (90%). Two patients with a sinus venosus defect and one each with a sinus venosus defect plus partial anomalous pulmonary venous connection, partial anomalous pulmonary venous connection without an atrial septal defect and a sinoseptal defect were missed. Of 109 patients without catheterization, a correct morphologic diagnosis was made before surgery in 92 (84%). Nine patients with a sinus venosus defect, three with sinus venous defect and partial anomolous pulmonary venous connection, four with partial anomalous pulmonary venous return without an atrial septal defect and one with a secundum defect were incorrectly diagnosed.(ABSTRACT TRUNCATED AT 250 WORDS)

Marked paradoxical septal motion associated with an early diastolic heart sound

The findings in four patients with marked paradoxical septal motion and an unusual early diastolic sound are presented. Each patient had markedly abnormal right ventricular function. Phonocardiograms, apexcardiograms, and echocardiograms showed the sound to precede the expected timing of a third heart sound and to coincide with the peak leftward displacement of the paradoxically moving septum in early diastole. In two patients the sound was also accompanied by third and fourth heart sounds, revealing a total of five heart sounds on phonocardiographic studies. The sound appeared to originate from the sudden deceleration of the septal mass as it moved leftward during ventricular relaxation.

Noninvasive assessment of right ventricular systolic pressure in atrial septal defect: analysis of the end-systolic configuration of the ventricular septum by two-dimensional echocardiography

This study was performed to determine if 2-dimensional echocardiography (2-D echo) can be used to predict right ventricular (RV) systolic pressure. Ninety-one patients with atrial septal defect were studied prospectively. Analysis of the end-systolic configuration of the ventricular septum (VS) in the short-axis 2-D echocardiogram allowed classification of patients into 4 groups: type A (67 patients)--the VS was more circular at end-systole than at end-diastole; type B (9 patients)--the VS curvature at end-systole was same as or further flattened compared with that at end-diastole; type C (9 patients)--the VS was straight at end-systole; type D (6 patients)--the VS curvature at end-systole was reversed so that it was convex toward the left ventricle. Between these types, the RV pressure was different. The RV systolic pressure ranged from 18 to 55 mm Hg (mean 34 +/- 1) in type A, 46 to 55 mm Hg (50 +/- 1) in type B, 60 to 76 mm Hg (66 +/- 2) in type C, and 72 to 118 mm Hg (93 +/- 7) in type D. The RV systolic pressure was statistically different between types except for types C and D. These data indicate that the end-systolic configuration of the VS in the short-axis 2-D echocardiogram may be useful for the semiquantitative assessment of the RV systolic pressure in patients with atrial septal defect.

M-mode and two-dimensional contrast echocardiography in adult patients with atrial septal defects

M-mode and two-dimensional echocardiographic studies, with and without contrast injection, were performed in 14 adult patients with clinical and radiological signs of atrial septal defects. Two-dimensional contrast echocardiography was found to be the most sensitive technique, allowing a definitive diagnosis to be made noninvasively in 12 patients (86%) of those patients studied. M-mode contrast echocardiography demonstrated an atrial shunt in 6 patients (43%). Regular two-dimensional echocardiography produced a high proportion of false-positive and false-negative results, while the findings on M-mode echocardiography are sensitive but nonspecific. All 14 patients described had the diagnosis confirmed on cardiac catheterization. Performance of the Valsalva maneuver during contrast echocardiography was found to be diagnostically unhelpful. The findings suggest that contrast echocardiography, particularly two-dimensional, is an effective, noninvasive diagnostic technique to be applied on clinical suspicion of atrial septal defects.

Diastolic ventricular septal motion in atrial septal defect: analysis of M-mode echocardiograms in 31 patients

Previous echocardiographic studies suggest that diastolic motion of the ventricular septum reflects relative filling of the right and left ventricles. We studied 31 patients with atrial septal defect by M-mode echocardiography. Early diastolic posterior ventricular septal motion (DPSM) occurred in all patients. Measurement of DPSM correlated with pulmonary to systemic flow ratios (Qp:Qs) (r = 0.64, p less than 0.001). All 15 patients with DPSM greater than 5 mm had a Qp:Qs greater than 2.5:1, whereas only 8 of 16 patients with DPSM less than 5 mm had a shunt this large (p less than 0.003). DPSM greater than 5 mm in patients with atrial septal defect is a specific but not sensitive echocardiographic sign of a large left-to-right shunt. Our findings substantiate the hypothesis that diastolic motion of the ventricular septum reflects relative filling of the ventricles.

Echocardiographic assessment of left ventricular structure and function in hypertension. Methodology

M-mode and two-dimensional echocardiography now provide an armamentarium of noninvasive techniques that permit assessment of left ventricular pump function, quantitation of afterload, a load-independent assessment of contractile state, and quantitation of pressure overload hypertrophy. Combined application of these methods to problems in the assessment of hypertensive heart disease can clarify both disease mechanisms and therapeutic effects by identifying the contributions of changes in myocardial mass, alterations in contractile state and variations in afterload to a given phenomenon.

Interventricular septal configuration as a predictor of right ventricular systolic hypertension in children: a cross-sectional echocardiographic study

Abnormal interventricular septal position and motion have been noted in patients with right ventricular pressure overload. The quantitative relationship between this alteration in septal configuration and the severity of right ventricular systolic hypertension has not been previously reported. We used cross-sectional echocardiography to assess the radius of septal curvature at end-diastole, midsystole, and end-systole in 20 normal children and 29 children (ages 2 weeks to 20 years) undergoing cardiac catheterization for a variety of congenital cardiac disorders. The measured septal radius of curvature (r) was normalized by the ideal radius (ri) for the left ventricular cavity area and then expressed as normalized septal curvature [l/(r/ri)]. A slight leftward shift and flattening of the interventricular septum occurred in the course of normal systolic contraction (mean +/- SEM normalized curvature at end-diastole 0.92 +/- 0.03 and at end-systole 0.85 +/- 0.02; p less than .05). Marked exaggeration of this configurational change occurred in patients with right ventricular systolic hypertension (right ventricular systolic pressure greater than 50% systemic pressure), with progressive loss of curvature from end-diastole (0.45 +/- 0.05) to end-systole (0.19 +/- 0.06). Normalized septal curvature correlated well with relative right ventricular systolic pressure at all three sampling periods, with the best correlation at end-systole (r = .86). End-systolic flattening of the interventricular septum thus proved to be a sensitive marker for right ventricular systolic hypertension.

Evaluation of right ventricular volume and ejection fraction in children by two-dimensional echocardiography

We estimated right ventricular volume and ejection by two-dimensional echocardiography (2DE) and compared the measurements with those obtained by right ventricular cineangiography (ANGIO) in 20 children whose ages ranged from 1 month to 10 years and who had a variety of congenital defects. The two echocardiographic planes used for calculating volume were the apical four-chamber (A4C) and parasternal short-axis (SA) planes. End diastolic volume (EDV) and end systolic volume (ESV) were calculated from these planes by single-plane area-length methods. The EDV and ESV were uniformly underestimated, but the estimate of ejection fraction (EF) was satisfactory. For EF, r = 0.83 from the apical four-chamber view and r = 0.78 from the short-axis view. The axes of the two echocardiographic planes passed through different segments of the right ventricle (RV) and we found that the value given by adding the volumes obtained from the two single-plane segments correlated quite well with the value obtained by angiography: for EDV, 2DE = 0.62 ANGIO + 7.0, r = 0.81, standard error of the estimate (s.e.e.) = 15.4 ml; for ESV, 2DE = 0.82 ANGIO + 1.4, r = 0.85, s.e.e. = 6.5 ml; and for EF, 2DE = 0.66 ANGIO + 17.8, r = 0.82, s.e.e. = 7.4 ml. Two-dimensional echocardiography can be used to evaluate right ventricular EF derived from volume measurements or from each of the echocardiographic planes of which, in our series, the apical four-chamber EF provided the better correlation.

Primary pulmonary hypertension: M-mode and two-dimensional echocardiographic findings

In two young men subsequently found to have primary pulmonary hypertension, echocardiographic findings suggested an atrial septal defect. Additionally, contrast echocardiography demonstrated right-to-left shunting at the atrial level. Cardiac catheterization demonstrated severe pulmonary hypertension with patent foramen ovale. Thus, primary pulmonary hypertension may result in findings similar to atrial septal defect on echocardiography, particularly if a foramen ovale is present.

Dynamics of the interventricular septum and free ventricular walls during blood volume expansion and selective right ventricular volume loading in dogs

To examine whether the right ventricle responds differently to blood volume expansion and selective right ventricular volume loading, segment lengths in the interventricular septum and the free walls of both ventricles and right ventricular septal-to-free-wall-distance were measured by an ultrasonic technique in open-chest dogs. Blood volume expansion increased segment lengths at all recording sites in proportion to stroke volume. Selective right ventricular volume loading induced by opening a shunt between the pulmonary artery and the superior vena cava increased right ventricular stroke volume by 40-80%; end-diastolic segment length and myocardial shortening increased in the septum and free wall of the right ventricle whereas left ventricular stroke volume and segment length decreased. Comparison of data obtained before and after opening of the shunt indicated that changes in myocardial dynamics of the right ventricle and septum accounted for approximately 30% of the increase in right ventricular stroke volume. However, both end-diastolic dimension and systolic shortening of the right ventricular septal-to-free-wall distance were larger during right ventricular volume loading than during blood volume expansion. Thus, most of the increase in stroke volume during selective right ventricular volume loading is caused by a change in the configuration of the right ventricle.