Long-term outcome of patients operated for large ventricular septal defects with increased pulmonary vascular resistance

BACKGROUND: There is a paucity of data regarding the long-term outcome of patients operated for ventricular septal defect with severe pulmonary arterial hypertension and elevated pulmonary vascular resistance. METHODS AND RESULTS: We evaluated the long-term follow-up results of a selected cohort of patients with nonrestrictive ventricular septal defect and elevated pulmonary vascular resistance (>6 Wood units). Thirty-eight patients, median age 7.5 years (range 6 months-27 years), with nonrestrictive ventricular septal defect with severe pulmonary hypertension were operated between 1985 and 1996 at our institute. Preoperative pulmonary vascular resistance, ratio of pulmonary blood flow to systemic blood flow, and ratio of pulmonary vascular resistance to systemic vascular resistance were 7.63+/-1.8 Wood units, 1.9+/-0.48, and 0.41+/-0.12, respectively. The majority (68.4%) had perimembranous ventricular septal defect. Thirty patients (79%) had a good outcome and were asymptomatic at a mean follow-up of 8.7 years, with significant reduction in pulmonary artery pressures. Eight patients (21%) had a poor outcome, which included 5 immediate postoperative deaths, 1 late death and 2 surviving patients with persistent severe pulmonary arterial hypertension. There was no significant difference regarding hemodynamic parameters at baseline between those who had a good outcome and those who did not. Eleven patients with a preoperative pulmonary blood flow to systemic blood flow ratio of <2:1. who had a good outcome following surgery, underwent repeat catheterization at follow-up. There was a significant reduction in their mean pulmonary vascular resistance (8.03+/-1.4 v. 4.16+/-1.6 Wood units, p=0.001) and pulmonary vascular resistance to systemic vascular resistance ratio (0.41+/-0.12 v. 0.19+/-0.06, p=0.05). CONCLUSIONS: The late results of surgery on this selected group of patients with nonrestrictive ventricular septal defect with high pulmonary vascular resistance are encouraging. Operative correction of the ventricular septal defect should be actively considered in all children presenting with nonrestrictive ventricular septal defect with a significant left-to-right shunt, despite moderately elevated pulmonary vascular resistance. Even among older patients with ventricular septal defect and moderately elevated pulmonary vascular resistance, there is a specific group that does well after operation.     

Noninvasive estimation of right ventricular systolic pressure in ventricular septal defect by a continuous wave Doppler technique

Noninvasive determination of right ventricular systolic pressure was attempted in 27 patients with ventricular septal defect based on the peak velocity of left-to-right shunt flow as measured in the right ventricle by a continuous wave Doppler technique. The systolic pressure gradient between the ventricles (delta p: mmHg) was calculated according to the simplified Bernoulli's formula, delta p = 4 V2, where V (m/sec) is the peak velocity of the left-to-right shunt flow. Right ventricular systolic pressure was determined by subtracting delta p from the systolic blood pressure measured in the upper arm, which was regarded as the left ventricular systolic pressure. The peak velocity of left-to-right shunt flow could be measured in all patients except one with muscular ventricular septal defect, and values ranged from 0.6 to 4.8 m/sec. The peak velocity of left-to-right shunt flow decreased inversely with the increase in right ventricular systolic pressure. The values of right ventricular systolic pressure determined by the continuous wave Doppler technique correlated highly (r = 0.820) with those determined by cardiac catheterization. The peak velocity of left-to-right shunt flow also showed high negative correlations with the pulmonary to systemic pressure ratio (r = -0.876) and pulmonary to systemic resistance ratio (r = -0.855). These results indicate that the continuous wave Doppler technique is clinically useful for determination of right ventricular systolic pressure as well as the pulmonary to systemic pressure ratio and pulmonary to systemic resistance ratio.     

Noninvasive evaluation of left-to-right shunts by pulsed Doppler echocardiography

The systemic and pulmonary blood flows and the ratio of pulmonary to systemic flow were noninvasively evaluated by pulsed Doppler echocardiography in 25 children with left-to-right shunts. Fourteen patients had atrial septal defect and 11 had ventricular septal defect. In patients with atrial septal defect, right ventricular stroke volume was obtained from the recordings of mean velocity flow and the diameter at the level of pulmonary valve in short-axis view. The left ventricular stroke volume was evaluated from the suprasternal approach by positioning the sample volume within the ascending aorta just above the valvar leaflets. In children with ventricular septal defect, the pulmonary blood flow was determined at the level of the mitral orifice, whereas the systemic blood flow was estimated from the ascending aorta. The systemic and pulmonary blood flows and their ratio determined by pulsed Doppler echocardiography in the 25 patients examined, were compared using simple linear regression analysis with the results obtained by cardiac catheterization. The ratio of pulmonary-to-systemic flow showed an excellent correlation in patients with atrial septal defect (r = 0.82) and in those with ventricular septal defect (r = 0.79). Our study validates the accuracy of cross-sectional Doppler echocardiography, especially for minimizing some possibility of errors in the presence of left-to-right shunts by employing new approaches.     

Analysis of pulmonary venous flow velocity patterns in hypertensive hearts: its complementary value in the interpretation of mitral flow velocity patterns.

Although the Doppler mitral flow velocity pattern changes in accordance with the degree of left ventricular diastolic dysfunction, it is "normalized" in the presence of heart failure. In this study the pulmonary venous flow velocity pattern was characterized in 43 hypertensive patients with and without heart failure to clarify whether analysis of the pulmonary venous flow velocity pattern provides complementary information in the interpretation of the mitral flow velocity pattern. The mitral flow velocity pattern in 32 hypertensive patients without heart failure was characterized by decreases in the peak early diastolic filling velocity (E) and the ratio of E to peak filling velocity at atrial contraction. The mitral flow velocity pattern was "normalized" in 11 patients with heart failure, with no differences in any mitral flow velocity pattern indexes as compared with 24 normal subjects. The pulmonary venous flow velocity pattern in hypertensive patients without heart failure was characterized by a decreased peak diastolic forward flow velocity (D) and an increased ratio of peak systolic forward flow velocity (S) to D (S/D ratio). In patients with heart failure, D was higher and the S/D ratio was lower compared with hypertensive patients without heart failure (p less than 0.01, p less than 0.01) and normal subjects (p less than 0.01, p less than 0.01). Thus the pulmonary venous flow velocity pattern appeared to be more reliable than the mitral flow velocity pattern in differentiating subgroups of patients with hypertension. Analysis of the pulmonary venous flow velocity pattern in conjunction with the mitral flow velocity pattern provides important and complementary information in the interpretation of the mitral flow velocity pattern in hypertensive patients with and without heart failure.     

Pulsed Doppler assessment of left ventricular diastolic function in atrial septal defect

From January 1986 through December 1990, we used pulsed Doppler echocardiography to evaluate left ventricular diastolic function in 43 patients with an ostium secundum atrial septal defect. The study population included 27 females and 16 males, whose ages ranged from 6 to 58 years (mean, 26 years). The patients were grouped according to degree of pulmonary hemodynamic impairment: patients in Group 1 (n = 6) had severe pulmonary hypertension, those in Group 2 (n = 10) had mild-to-moderate pulmonary hypertension, and those in Group 3 (n = 27) had no pulmonary hypertension. For comparison, we also evaluated 30 healthy individuals. All control subjects had a normal left ventricular filling profile. Of the 43 study patients, 8 (19%) showed Doppler echocardiographic signs of impaired left ventricular relaxation, including a prolonged left ventricular isovolumic relaxation time, decreased peak left ventricular diastolic inflow velocity, and a prolonged mean deceleration time of early diastolic flow velocity. Of these 8 patients, 5 were from Group 1, 1 was from Group 2, and 2 were from Group 3. A positive correlation (r = 0.66; standard error of the estimate = 0.32) was found between the late-to-early left ventricular diastolic inflow velocity ratio and the pulmonary-to-systemic vascular resistance ratio. Our results showed impaired left ventricular relaxation in 8 (19%) of patients with atrial septal defect; 5 of these patients had severe pulmonary hypertension. We therefore conclude that left ventricular diastolic dysfunction is closely related to severe pulmonary hypertension.     

Clinical characteristics and diagnosis of double-orifice left atrioventricular valve associated with other congenital heart disease

Four cases of double-orifice left atrioventricular (AV) valve are reported. Three of the four patients with double-orifice left AV valve had other associated congenital heart diseases, and the fourth had double-orifice left AV valve alone. A patient with associated ventricular septal defect, who presented with pulmonary congestion and hypertension, suffered from severe heart failure. However, these symptoms improved with the spontaneous closure of the ventricular septal defect. The patient with double-orifice left AV valve alone showed no cardiac symptoms. Two-dimensional and Doppler echocardiography did not detect the double-orifice left AV valve in two of the four patients. More recently, the echocardiographic technique has allowed a noninvasive and more frequent detection of this abnormality. But both of these patients had left-to-right atrial shunt and subsequent reduced transmitral flow and left ventricular volume, which may have made it difficult to detect the morphological and hemodynamic characteristics of double-orifice left AV valve. Careful and repeated echocardiographic observation of mitral configuration is required to determine the presence of double-orifice left AV valve when heart disease is associated with a left-to-right atrial shunt.     

The palliative Mustard operation for double outlet right ventricle or transposition of the great arteries associated with ventricular septal defect, pulmonary arterial hypertension, and pulmonary vascular obstructive disease. A report of eight patients.

Five patients with double outlet right ventricle, ventricular septal defect, pulmonary arterial hypertension and pulmonary vascular obstructive disease and three patients with complete d-transposition of the great arteries, ventricular septal defect, pulonary arterial hypertension and pulmonary vascular obstructive disease underwent an elective Mustard baffle operation. The ventricular septal defect was not closed. A large patent ductus arteriosus was divided in three patients. Seven of the eight patients are alive five to 32 months after surgery; one patient died 11 months after surgery. Cyanosis, dyspnea on exertion, and exercise limitation improved initially in all and has persisted in the survivors. In pre and postoperative hemodynamic studies in four patients, systemic arterial oxygen saturation and effective pulmonary blood flow increased from mean values of 70% to 90% and 1.7/min/m2 to 3.3 L/mon/m2, respectively. Absolute systemic and pulmonary flows, and pressures and resistances, were not significantly altered. Criteria for selection of patients with transposition of the great arteries of double outlet right ventricle who would benefit from a palliative Mustard procedure (Mustard atrial baffle without closure of the ventricular spetal defect) are: 1) severe symptoms; 2) pulmonary arteiral hypertension (75% systemic) with pulmonary vascular obstructive disease; and 3) pulmonary artieral oxygen saturation greater than systemic (ascending aorta) arterial oxygen saturation by approximately 10%.     

Hemodynamic evaluation before and after balloon atrial septostomy in patients with transposition of the great arteries using pulsed Doppler echocardiography

In nine patients with transposition of the great arteries, hemodynamic changes after the initial balloon atrial septostomy (BAS) were investigated using pulsed Doppler echocardiography and cardiac catheterization. Patients consisted of five males and four females, who ranged in age from zero to 82 days (median, one day). All but one who had ventricular septal defect had no associated cardiac anomalies other than patent ductus arteriosus. Prostaglandin E1 was administered before and after BAS to four patients who had hypoxemia. At cardiac catheterization, right and left atrial pressures and arterial oxygen partial pressure were measured. Using pulsed Doppler echocardiography, the time-velocity curve was recorded at the tricuspid and mitral valves, pulmonary artery, ascending aorta and interatrial septum. The maximum diastolic velocity was measured from the tricuspid and mitral valve time-velocity curves. The product of the time-velocity integral and heart rate was measured from the time-velocity recordings at the pulmonary artery and ascending aorta. The duration of the left-to-right shunt at the foramen ovale was measured and was normalized by corresponding R-R intervals on the electrocardiogram. After BAS, left atrial pressures and pressure gradients between both atria decreased significantly (p less than 0.01). Arterial oxygen partial pressure increased from 24.4 +/- 7.2 to 40.4 +/- 6.0 mmHg (p less than 0.01). The maximum flow velocity at the tricuspid valve increased significantly (p less than 0.01), but that at the mitral valve showed no significant change after BAS. The velocity time integral of the aorta increased significantly (p less than 0.01), but that of the pulmonary artery did not.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cross-sectional and M-mode echocardiographic study on ventricular septal defect.

One hundred and eight patients with ventricular septal defect (VSD) including 20 operated patients were studied with real time cross-sectional echocardiography combined with M-mode echocardiography. The subjects were divided into 3 groups according to the cross-sectional echocardiographic findings. Group 1 included 34 patients in whom the defect area of interventricular septum (IVS) was demonstrated and they were diagnosed as VSD solely with this method. The majority of the patients in this group showed marked pulmonary hypertension and severe cardiac symptoms. Group 2 consisted of 13 patients who showed abruptly posterior movement of IVS toward the left ventricular cavity at early diastole and were suspected of VSD. Group 3 consisted of 41 patients with VSD showing normal cross-sectional echocardiograms without echo discontinuity of IVS. This group had a small defect of IVS with near normal pulmonary artery pressure. The analysis of cross-sectional echocardiogram combined with M-mode echocardiogram and the data of other cardiac examinations revealed that group 1 showed a larger left-to-right shunt at the ventricular level, severer pulmonary hypertension and more marked heart enlargement than groups 2 and 3. The patients with visualized defect of IVS had severe cardiac signs and symptoms and were indicated for the cardiac surgery. In the postoperative patients, the patch echo was clearly recognized as a linear strong echo. Real time cross-sectional echocardiography is available to visualize directly the defect of IVS in the majority of the patients with VSD and to estimate the condition of patients with this lesion.     

Interauricular communication with severe pulmonary hypertension in children. Apropos of 9 cases

The authors report 9 cases of atrial septal defect with sever pulmonary hypertension in 7 girls and 2 boys under 10 years of age. These cases represent 3.5% of the 255 cases of atrial septal defect in this age group seen at the Hopital Cardiologique of Lille between 1970 and 1985. Group I comprised 3 children with obstructive pulmonary hypertension from the start; two died, one is still alive after 3 years. Group II was composed of 3 children who presented, at first haemodynamic evaluation, with severe but non-obstructive pulmonary hypertension; the hypertension rapidly became obstructive in 2 of them despite digitalis-diuretic therapy; the third child died after surgical correction. The 3 children in group III had normal or slightly raised pulmonary arterial pressure at first haemodynamic evaluation; one of them initially had a right ventricle-pulmonary artery functional gradient of 45 mmHg, which did not prevent the subsequent development of obstructive pulmonary hypertension; the other 2 patients were operated upon 10 months and 4 years later respectively, as they presented with severe pulmonary hypertension; one of these 2 children died postoperatively, the third one developed obstructive pulmonary hypertension. Contrary to what is generally believed, severe pulmonary hypertension is not exceptional in children with atrial septal defect, and it has a poor prognosis. The mechanism underlying the development of this pulmonary hypertension is unclear, but individual susceptibility to excessive blood flow is probable, as is the role played by bronchopulmonary infections frequently noted in these patients' history.     

Importance of spontaneous closure of the ventricular part in atrioventricular septal defect.

The clinical features, hemodynamic changes and prognosis of 21 children with simple atrioventricular septal defect (3 associated with patent ductus arteriosus) were studied during a follow-up period of 1 month to 13 3/12 years (median 3 years). Six patients had spontaneous closure of the ventricular part of the defect within 22.2 +/- 27.7 months (Group I). The symptoms and signs of failure to thrive, frequent respiratory tract infections and congestive heart failure were more common in patients without spontaneous closure of the ventricular part of atrioventricular septal defect (Group II) than in patients in Group I. The Qp/Qs ratio, pulmonary vascular resistance and pulmonary to systemic resistance ratio were also higher in Group II than in Group I. In spite of a higher postoperative mortality rate and a higher incidence of transient complete heart block, the children in Group II also had a significantly higher (p less than 0.005) preoperative mortality rate than those in Group I. In conclusion, if the ventricular part of the atrioventricular septal defect closed or was closing spontaneously, symptoms and signs were less severe and there was a better prognosis.     

Double outlet right ventricle: clinical spectrum and prognosis.

Patients with double outlet right ventricle can be separated into four distinct groups. In the largest (Group III), patients have a subaortic ventricular septal defect and pulmonary stenosis and clinically resemble patients with tetralogy of Fallot. In the next largest group (Group I), patients have a subpulmonry ventricular septal defect and no pulmonary stenosis and clinically resemble children with D-transposition of the great arteries and a ventricular septal defect. These patients have a high rate of coarctation of the aorta leading to early congestive heart failure, and their overall prognosis is poor. In the next largest group (Group II), patients have a subaortic ventricular septal defect and no pulmonary stenosis. Their presentation is similar to that of children with a large ventricular septal defect and pulmonary hypertension. In the smallest group (Group IV), the ventricular septal defect is uncommitted. Survivors in this group also clinically resemble children with a large ventricular septal defect and pulmonary hypertension. When present, coarctation of the aorta and severe mitral valve abnormalities greatly influence the prognosis in double outlet right ventricle. Although the prevalence of associated cardiac abnormalities is large, asplenia, polysplenia, chromosomal abnormalities and other congenital noncardiac abnormalities occur in only 12.5% of patients with double outlet right ventricle.     

Left ventricular filling characteristics in pulmonary hypertension: a new mode of ventricular interaction.

OBJECTIVE--To examine the effects of pulmonary hypertension on left ventricular diastolic function and to relate the findings to possible mechanisms of interdependence between the right and left sides of the heart in ventricular disease. DESIGN--A retrospective and prospective analysis of echocardiographic and Doppler studies. SETTING--A tertiary referral centre for both cardiac and pulmonary disease. PATIENTS--29 patients with pulmonary hypertension (12 primary pulmonary hypertension, 10 pulmonary fibrosis, five atrial septal defect (ASD), and two scleroderma) were compared with a control group of 10 patients with an enlarged right ventricle but normal pulmonary artery pressure (six ASD, one after ASD closure, one ASD and pulmonary valvotomy, one tricuspid valve endocarditis and repair, and one pulmonary fibrosis). None had clinical or echocardiographic evidence of intrinsic left ventricular disease. MAIN OUTCOME MEASURES--M mode echocardiographic measurements were made of septal thickness, and left and right ventricular internal cavity dimensions. Doppler derived right ventricular to right atrial pressure drop, and time intervals were measured, as were isovolumic relaxation time, and Doppler left ventricular filling characteristics. RESULTS--The peak right ventricular to right atrial pressure gradient was (mean (SD)) 60 (16) mm Hg in pulmonary hypertensive patients, and 18 (5) mm Hg in controls. The time intervals P2 to the end of the tricuspid regurgitation, and P2 to the start of tricuspid flow were both prolonged in patients with pulmonary hypertension compared with controls (115 (60) and 120 (40) v 40 (15) and 45 (10) ms, p values less than 0.001). Pulmonary hypertensive patients commonly had a dominant A wave on the transmitral Doppler (23/29); however, all the controls had a dominant E wave. Isovolumic relaxation time of the left ventricle was prolonged in pulmonary hypertensive patients compared with controls, measured as both A2 to mitral valve opening (80 (25) v 50 (15) ms) and as A2 to the start of mitral flow (105 (30) v 60 (15) ms, p values less than 0.001). The delay from mitral valve opening to the start of transmitral flow was longer in patients with pulmonary hypertension (30 (15) ms) compared with controls (10 (10) ms, p less than 0.001). At the time of mitral opening there was a right ventricular to right atrial gradient of 12 (10) mm Hg in pulmonary hypertensive patients, but this was negligible in controls (0.4 (0.3) mm Hg, p less than 0.001). CONCLUSIONS--Prolonged decline of right ventricular tension, the direct result of severe pulmonary hypertension, may appear as prolonged tricuspid regurgitation. It persists until after mitral valve opening on the left side of the heart, where events during isovolumic relaxation are disorganised, and subsequent filling is impaired. These effects are likely to be mediated through the interventricular septum, and this right-left ventricular asynchrony may represent a hitherto unrecognised mode of ventricular interaction.     

Prenatal role of the ductus arteriosus in absent pulmonary valve syndrome

Absent pulmonary valve with ventricular septal defect is associated with ductal agenesis and markedly dilated main and branch pulmonary arteries. The less common variant with intact ventricular septum generally exhibits a patent ductus and smaller branch pulmonary arteries, and may be associated with tricuspid atresia. We identified 7 patients with the prenatal diagnosis of absent pulmonary valve, 5 with ventricular septal defect (Group 1) and 2 with an intact ventricular septum (Group 2). Imaging, color Doppler, and pulsed-Doppler recordings were analyzed. The branch and main pulmonary arteries were measured and expressed as a ratio with the descending aorta. Pulmonary regurgitation time (PRT) and diastolic acceleration time (DAT) were derived, and DAT/PRT was calculated to characterize diastolic pulmonary flow. Group 1 patients all had a large ventricular septal defect, normal biventricular size and function, and dilated main and branch pulmonary arteries. Group 2 patients had dilated main but smaller branch pulmonary arteries, moderate right ventricular dilation with severe dysfunction, and limited or absent tricuspid inflow. Group 1 demonstrated shorter acceleration time and earlier peak velocity, resulting in a smaller DAT/RT ratio. We speculate that free communication between the fetal aorta and the ventricles may limit atrial inflow and elevate diastolic pressure, affecting cardiac output, ventricular function, and atrioventricular valve development. With an intact ventricular septum, these physiologic and anatomic repercussions are limited to the right ventricle, but with a ventricular septal defect, both ventricles would experience similar consequences and cardiac performance could be critically impaired.     

Pulmonary blood flow distribution in transposition of the great arteries

Pulmonary blood flow distribution was studied by scintillation scanning of the lungs after the infusion of iodine-131-labeled macroaggregates of human albumin before and after the Mustard operation in 53 patients with transposition of the great arteries. The patients were classified as follows: Group I (24 infants with uncomplicated transposition of the great arteries); Group II (18 patients with transposition and ventricular septal defect); and Group III (11 patients with transposition, ventricular septal defect and pulmonary obstruction).Before operation, 21 patients had a normal distribution of pulmonary blood flow, 10 had preferential flow to the right lung and 2 had preferential flow to the left lung. After operation, 19 had a normal pattern of pulmonary blood flow, 21 had preferential flow to the right lung and 3 had preferential flow to the left lung. The scanning studies have proved helpful in follow-up of patients to rule out recurrence of the shunt, pulmonary or systemic venous obstruction, development of pulmonary hypertension and occlusion of a palliative systemic-pulmonary shunt.     

A neonate with mitral stenosis due to accessory mitral valve,ventricular septal defect,and patent ductus arteriosus: changes in echocardiographical findings during the neonatal period

 A female neonate with mitral stenosis due to accessory mitral valve with ventricular septal defect and patent ductus arteriosus is described. She was referred to our hospital because of neonatal asphyxia. Asphyxia was improved by ventilator support, but rapid deterioration of respiration with pulmonary congestion and hemorrhage appeared 8 days after birth. Echocardiography revealed an accessory mitral valve attached to the anterior mitral leaflet with a perimembranous ventricular septal defect and patent ductus arteriosus. Although there were no echocardiographical findings indicating mitral stenosis on admission, the mitral stenosis blood flow patterns were detected by color and pulsed Doppler examination performed on the eighth day after admission. Transaortic resection of accessory mitral valve tissue was performed with patch closure of the ventricular septal defect and ligation of the ductus arteriosus 35 days after birth. After operation, pulmonary congestion and hemorrhage were improved. Postoperative echocardiography showed complete resection of the accessory mitral valve and no mitral insufficiency. We concluded that the combination of the accessory mitral valve and left-to-right shunt due to ventricular septal defect or patent ducturs arteriosus might have led to a critical hemodynamic condition due to relative mitral stenosis in the neonatal period with the decrease in pulmonary vascular resistance. Received: May 30, 2002 / Accepted: September 6, 2002 Correspondence to T. Ito     

Assessment of left-to-right atrial shunting after percutaneous mitral valvuloplasty by transesophageal color Doppler flow-mapping

To evaluate left-to-right shunts after percutaneous balloon mitral valvuloplasty, we studied 15 consecutive patients by using transesophageal color Doppler flow-imaging system. Transesophageal color Doppler examinations were performed five times in each patient (before valvuloplasty and 1 day, 1 week, 1 month, and 6 months after valvuloplasty). No shunt flow was observed before valvuloplasty. On 1 day after mitral valvuloplasty, transesophageal color Doppler echocardiography demonstrated left-to-right shunts in 13 (87%) of 15 patients. However, a significant oxygen step-up was present in the right heart in only one patient. The mean diameter of the interatrial septal defect detected by transesophageal two-dimensional echocardiography was 1.8 +/- 1.0 mm. The mean velocity of left-to-right shunting flow measured by high-pulse repetition frequency Doppler technique was 0.83 +/- 0.38 m/sec. One week after the procedure, left-to-right shunt flow was detected in 11 (73%) patients. One month after valvuloplasty, left-to-right shunting flow was detected in seven (47%) of 15 patients. There was a significant decrease in the diameter of an interatrial septal defect between 1 day and 1 week (p less than 0.01), between 1 week and 1 month (p less than 0.01), and between 1 month and 6 months (p less than 0.05). Six months after valvuloplasty, left-to-right shunting flow remained in three (20%) patients. By using transthoracic color Doppler echocardiography, we detected left-to-right shunting flow in two patients on 1 day after the procedure.(ABSTRACT TRUNCATED AT 250 WORDS)     

Angiocardiographic evaluation of the left ventricular function in adult and pediatric subjects with interatrial defect of the ostium secundum type]

In order to assess left ventricular function in adults and children with ostium secundum atrial septal defect (ASD), 42 patients were examined by hemodynamic and angiocardiographic techniques. Patients were divided into three groups: Group I, 18 patients (mean age 42 years) with ASD; Group II, 14 patients (mean age 9 years) with ASD; Group III, 10 patients without cardiopathies who represented the control group. The following parameters of ventricular function were assessed: left ventricular end diastolic volume, global and regional left ventricular ejection fraction, left ventricular telediastolic pressure, mean pulmonary artery pressure, the ratio between pulmonary flow and systemic flow (QP/QS). Group I patients showed higher values of left ventricular end diastolic pressure and mean pulmonary artery pressure (16 +/- 0.6 mmHg; 33 +/- 1.5 mmHg) in relation to those of Group II (5.1 +/- 0.4 mmHg; 14 +/- 1.4 mmHg) and Group III (8.1 +/- 0.5 mmHg; 18 +/- 1.6 mmHg). In both cases the difference was statistically significant (p less than 0.001). A significant difference (p less than 0.05) was also noted in the incidence of mitral valve prolapse between patients in Group I and II. There was no significant difference (p = NS) however, between overall ejection fraction values in the three groups of patients; a lower regional ejection fraction (postero-basal segment) was recorded in Group I patients with mitral valve prolapse in comparison to patients in the other two groups (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

Right ventricular function in adults with pulmonary hypertension with and without atrial septal defect

Using equilibrium (gated) radionuclide ventriculography, right ventricular (RV) function was studied in 22 adults with pulmonary hypertension and in 16 patients without evidence of cardiac disease. To assess the effect of volume overload on RV performance in pulmonary hypertension, RV ejection fractions were compared in patients with and without left-to-right shunts due to atrial septal defect (ASD). In addition, the effect of ASD repair on RV function was examined. In 14 patients with pulmonary hypertension without RV volume overload (group I), the RV ejection fraction (0.35 ± 0.11, mean ± standard deviation [SD]) was significantly lower than in the normal group (0.47 ± 0.11, p < 0.01). In 8 patients with left-to-right shunts due to ASD (group II) and with RV systolic pressures similar to those in group I, the mean RV ejection fraction (0.53 ± 0.15) was normal and was significantly higher than in group I (p < 0.01). Right ventricular end-diastolic volumes, estimated from combined radionuclide and hemodynamic data, were higher (p < 0.01) in group II patients (171 ± 70 ml/m²) than in group I patients (70 ± 13 ml/m²). In 5 patients who underwent isolated shunt repair, mean RV ejection fraction decreased postoperatively from 0.57 ± 0.17 to 0.40 ± 0.12 (p < 0.05). It is concluded that (1) pulmonary hypertension frequently causes a decrease in RV systolic function due to abnormal afterload; (2) in patients with RV volume overload due to left-to-right shunt, systolic function, as measured by the ejection fraction, remains normal despite pulmonary hypertension, possibly through the Starling mechanism; and (3) RV systolic function often decreases after repair of an ASD.     

Quantitative structural analysis of pulmonary vessels in isolated ventricular septal defect in infancy.

Structural changes in the pulmonary circulation were studied in the lungs of 5 infants dying with ventricular septal defect. Applying precise quantitative morphological techniques to the pulmonary vessels, it was possible to correlate pathological change with clinical and haemodynamic findings, and to identify two patterns of response. Three of the infants (group I) ppresnted in cardiac failure with a large pulmonary blood flow, dilated and tortuous pulmonary arteries, and fewer intra-acinar vessels than normal. Medial hypertrophy was moderate and affected chiefly the larger arteries, i.e. those with a diameter greater than 200 mum. The other 2 infants (group 2) had a high pulmonary vascular resistance with an intermittent right-to-left shunt. The pulmonary arteries were of normal size and the reduction in the number of the arteries was less striking. Medial hypertrophy was greater than in the first group and affected all sizes of artery including those less than 200 mum in diameter. In both groups, muscle extended further along the axial pathway. Muscular hypertrophy was found also in the vein wall in most cases and, as with the arteries, was more severe in those with a higher pulmonary vascular resistance. The findings illustrate the variation in pulmonary vascular response in infants with a ventricular septal defect. It is suggested that in patients with a ventricular septal defect, arterial muscularity usually regresses after birth and a left-to-right shunt develops; secondary hypertrophy of the media then develops in reaponse to the shunt. Our findings also suggest, however, that in some infants arterial muscle fails to regress postnatally so that pulmonary blood flow is never high and a right-to-left shunt develops soon after birth.