Echocardiography and cardiac catheterization in the preoperative assessment of ventricular septal defect in infancy

Relationships between left heart chamber dilatation on echocardiography and left-to-right ventricle shunting quantified by cardiac catheterization in children with ventricular septal defects

Left atrium and/or left ventricle dilatation on echocardiography is considered to be an indication for closure of ventricular septal defects (VSD). No study has addressed the accuracy of using dilated left heart chambers when defining significant left-to-right shunting quantified by cardiac catheterization in isolated small or moderate VSDs. In this study, the relation between dilated left heart chambers, measured by echocardiography, and left-to-right ventricle shunting, quantified by cardiac catheterization, was evaluated in patients with isolated VSD. The medical records of all patients with isolated VSD who had undergone catheterization from 1996 to 2010 were examined retrospectively. Normative data for left heart chambers adjusted for body weight (BW) and body surface area (BSA) were used. The pulmonary-to-systemic flow ratio (Qp:Qs) was calculated by an oximetry technique. A total of 115 patients (mean age 7.3 ± 5 years) fulfilled the inclusion criteria. There was a statistically significant difference in terms of Qp:Qs between the patient groups with normal and dilated left heart chambers, when adjusted for BW and BSA (p = 0.001 and p = 0.002, respectively). But the relationships between Qp:Qs and left heart chamber sizes on echocardiography were not strong enough to be useful for making surgical decisions, as left heart chamber dilatation was not significantly associated with Qp:Qs ≥ 2 (p = 0.349 when adjusted for BW, p = 0.107 when adjusted for BSA). Left heart chamber dilatation was significantly associated with Qp:Qs ≥ 1.5 only when it was adjusted for BSA (for BW p = 0.022, for BSA p = 0.006). As a result, left heart chamber dilatation measured by echocardiography does not show significant left-to-right ventricle shunting, as quantified by catheterization. We still advocate that catheter angiography should be undertaken when left heart chambers are dilated in echocardiography in order to make decisions about closing small- to moderate-sized VSD.

Resonancia magnética cardiovascular en la cuantificación de los cortocircuitos de izquierda a derecha en los defectos septales cardiacos con hipertensión arterial pulmonar

INTRODUCTION AND OBJECTIVES

As cardiac septal defects are frequently associated with pulmonary arterial hypertension, hemodynamic assessment is essential before deciding on surgery. The aim of this study was to evaluate the use of cardiovascular magnetic resonance imaging for assessing cardiac shunts and for quantifying pulmonary artery systolic pressure in patients with cardiac septal defects.

METHODS

This cross-sectional study involved patients with cardiac septal defects and clinically suspected severe pulmonary arterial hypertension who had an indication for cardiac catheterization and in whom magnetic resonance imaging was not contraindicated. Each test's results were evaluated independently by two expert radiologists and interventional cardiologists who were blinded to the results of the other test. The procedures were compared using confidence limits and intraclass correlation coefficients.

RESULTS

The study involved 29 patients (18 female and 11 male) aged from 30 days to 18 years; seven had an atrial septal defect, 14 had a ventricular septal defect, and eight had an atrioventricular septal defect. The correlation coefficients for measurements made using the two procedures were 0.80, 0.75, 0.81 and 0.58 for pulmonary output, systemic output, flow ratio, and systolic pressure in the pulmonary artery, respectively. Cardiovascular magnetic resonance tended to underestimate systemic output by 0.80 L/min, pulmonary output by 1.35 L/min, left-to-right shunt flow by 0.12 L/min, and systolic pressure in the pulmonary artery by 16.5 mmHg. The complication rate with cardiac catheterization was 31% compared with 3.4% with cardiovascular magnetic resonance imaging.

CONCLUSIONS

The evaluation of patients with cardiac septal defects and pulmonary arterial hypertension should initially be performed using noninvasive diagnostic techniques.

Real Time Three-Dimensional Echocardiography in Assessing Ventricular Septal Defects: An Echocardiographic-Surgical Correlative Study

BACKGROUND

Two-dimensional echocardiography (2DE) enhanced by combining with color Doppler technology has significant limitations in providing precise quantitative information, geometric assumptions to calculate chamber volume, mass, and ejection fraction. Reconstructed three-dimensional echocardiographic (3DE) systems (from multiple cross-sectional echocardiographic scans) are still cumbersome and time-consuming. Real time 3DE (RT-3DE) with shorter imaging time than with 3D reconstruction techniques can obtain qualitative and quantitative information on heart disorders. Our purpose was to investigate the feasibility and potential value of RT-3DE as a means of accurately and quantitatively estimating the size of VSD to correlate with the surgical findings.

MATERIALS AND METHODS

38 patients with VSD were examined with RT-3DE. 3D image database was postprocessed using TomTec echo 3D workstation. The results were compared with the results measured by 2 DE and surgical findings. RT-3DE produced novel views of VSD and improved quantification of the size of the defect. The sizes obtained from 3DE have equivalent correlation with surgical findings as diameter measured by 2DE (r = 0.89 vs r = 0.90). Good agreement between blinded observers was achieved by little interobserver variability.

CONCLUSION

RT-3DE offers intraoperative visualization of VSD to generate a "virtual sense of depth" without extending examining time. From an LV en face projection, the positions, sizes, and shapes of VSDs can be accurately determined to permit quantitative recording of VSD dynamics. It is a potentially valuable clinical tool to provide precise imaging for surgical and catheter-based closure of difficult perimembranous and singular or multiple muscular VSD.

Cardiac computed tomography compared to transthoracic echocardiography in the management of congenital heart disease

OBJECTIVES

To compare cardiac CT and transthoracic echocardiography (TTE) as diagnostic utilities in congenital heart disease (CHD) and to determine their advantages and limitations.

BACKGROUND

TTE is widely used in the evaluation of CHD. Recent reports suggested an increasing role of CT. However, there are few quantitative data on its diagnostic accuracy.

METHODS

We investigated a total of 162 patients (51.24% male; mean age: 16.06 +/-+/- 17.92) with congenital heart defects, who underwent electron beam CT (EBCT) and TTE between March 2002 and June 2005. We retrospectively analyzed a total of 667 findings, stratified for age and anatomic categories.

RESULTS

EBCT and TTE findings are concordant in patients below 1 year of age (85.43% agreement). EBCT had poor sensitivity and specificity in detecting anomalies of cardiac chambers (0.68, 0.58), but was useful for great arteries (0.91, 0.85). Furthermore, sensitivity and specificity were remarkably different in systemic venous return (0.93, 0.3) and coronary vessels (0.8, 0.33) because of "false positive" findings, which were later found to be most likely real findings not detectable by reference standard. The opposite was true for cardiac valves (0.66, 0.89) and septa (0.76, 0.91).

CONCLUSIONS

EBCT delineates findings related to systemic venous return and coronary vessels well due to simultaneous visualization of complex anatomy. This advantage does not seem to apply in patients below 1 year of age with better acoustic windows. TTE was found more suitable for cardiac valves and septal defects because of the availability of flow imaging.

Real-time 3-dimensional echocardiography in assessing atrial and ventricular septal defects: an echocardiographic-surgical correlative study

OBJECTIVE

The aim of this study is to explore the feasibility and the value of real-time 3-dimensional echocardiography (RT3DE) in quantitative evaluation of the size of atrial septal defect (ASD) and ventricular septal defect (VSD) and to correlate with the surgical findings.

METHODS

Thirty eight patients with ASD and/or VSD were examined with RT3DE. Three-dimensional image data-base was post-processed using 3D work-station. The results were compared with the results measured by 2-dimensional echocardiography and surgical findings.

RESULTS

RT3DE produced novel views of congenital septal defects and improved quantification of the size of the defect. The sizes obtained from 3DE have better correlation with surgical findings than diameter measured by 2-dimensional echocardiography (r = 0.69 vs r = 0.92).

CONCLUSIONS

RT3DE offers additional special information in congenital heart disease without extending examining time, permits quantitative recording of septal defect dynamics, and enhances the understanding of complex cardiac anatomy and elucidation of the disease mechanism. It is a potentially valuable clinical tool for diagnosing and managing patients with congenital heart disease.

Prevalence and development of additional cardiac abnormalities in 1448 patients with congenital ventricular septal defects

OBJECTIVE

To determine by modern echocardiographic techniques the prevalence and development of cardiac abnormalities associated with ventricular septal defect (VSD).

METHODS

Consecutive patients referred to a tertiary centre for paediatric cardiology and attenders at an adult congenital heart disease clinic had details of clinical outcome prospectively recorded. Patients with VSD in association with conotruncal abnormalities, atrioventricular septal defects, and univentricular heart were not included in the study.

RESULTS

1448 patients with VSD were assessed between 1991 and 1998. 1127 (78%) patients had isolated defects; of these 862 (76%) were perimembranous and 265 (24%) were muscular. Of the remainder, 284 (19.6% of the total population) patients had VSD associated with one other significant cardiac abnormality: 35 (2.4%) with two and two (0.1%) with three other abnormalities. The most common associated cardiac abnormalities were infundibular pulmonary stenosis (5.8%), aortic valve prolapse (3.6%), pulmonary valvar stenosis (2.7%), osteum secundum atrial septal defect (2.2%), persistent ductus arteriosus (1.9%), and coarctation of the aorta (1.5%). In the cohort of 743 patients followed up from birth, cumulative mortality was 4% by the age of 8 years and most deaths occurred within the first year of life in infants with associated genetic abnormalities such as trisomy 13 or 18. Of the 594 patients attending the adult congenital clinic with VSD, aortic regurgitation due to aortic root prolapse developed in 45 (7.6%) patients. Most of these cases were detected before the patient was 30 years old.

CONCLUSIONS

In 22% of patients with congenital VSD there were significant associated cardiac abnormalities. Some of these abnormalities, such as aortic prolapse and regurgitation or infundibular pulmonary stenosis, may develop or progress subsequently and therefore should be sought during the initial assessment and monitored during follow up. Follow up to the age of 30 years allows the detection of most cases of aortic regurgitation. The prognosis from VSD is excellent and the risk of endocarditis in a population informed of the need for antibiotic prophylaxis is small.

Echocardiographic assessment of obstructive lesions in atrioventricular septal defects

OBJECTIVES

We sought to determine the accuracy of transthoracic echocardiography (TTE) in identifying risk factors in patients with an atrioventricular septal defect (AVSD).

BACKGROUND

Atrioventricular septal defect is a common lesion, and many decisions about it are based on echocardiography alone. The identification of associated left-sided inflow and outflow obstructive lesions is important, as they are responsible for mortality and morbidity.

METHODS

Between 1983 to 1998, 549 patients with AVSD underwent repair. The TTE findings were correlated with surgery, angiocardiography, autopsy or postoperative TTE. Papillary muscle measurements were made in those with either a left ventricular outflow tract (LVOT) or left ventricular inflow abnormality and compared with those measurements from control subjects. Measurements of the LVOT were made in patients with an identified LVOT abnormality.

RESULTS

There were 63 missed lesions, decreasing over time. Double-orifice left atrioventricular valve (DOLAVV) and nonobstructive chordae in the LVOT were more often missed. Reoperation was performed to address a missed lesion in 2 of 68 patients. Two of 55 patients died of reasons related to a missed lesion. In 67% of patients, DOLAVV was missed. Abnormal papillary muscle angles were seen with either a LVOT abnormality or DOLAVV. High insertion of the anterolateral papillary muscle was a risk factor for death or residual LVOT obstruction. Abnormal LVOT measurements were found in patients with tunnel obstruction and those with an acquired subaortic ridge.

CONCLUSIONS

Transthoracic echocardiography provides accurate preoperative information on AVSD.

Pediatric cardiac surgery after exclusively echocardiography-based diagnostic work-up

This study was performed to evaluate the accuracy of exclusively non-invasive preoperative diagnostic work-up based on echocardiography and to assess the safety of cardiac surgery using this diagnostic approach in children with heart disease. During a 3. 5-year period, accuracy of preoperative (invasive and non-invasive) diagnostic work-up was prospectively tested by comparison with the intraoperative findings obtained by surgical inspection and transoesophageal echocardiography. Included were all consecutive 358 children undergoing cardiac surgery (except pulmonary artery bandings and ductus ligations) during the study period at our institution. Of the patients, 44% were operated on in infancy, 84% of procedures were on cardiopulmonary bypass. Echocardiography as the only preoperative imaging modality was used in 231 patients (65%), in the other children, a diagnostic catheter was done. Diagnostic errors occurred in 3.9% (n=5) of patients after diagnostic catheter and in 6.9% (n=16) of patients with echocardiography only. Major diagnostic errors (resulting in prolongation of cardiac bypass time) were observed at equal frequency in both groups (1.7% or four children in the echo-only group and 1.6% or two patients in the catheter group). In no case was the outcome affected by the previously unrecognized findings. It was shown that diagnostic cardiac catheterization could be avoided in a majority of pediatric patients prior to surgical palliation or correction of cardiac defects, without increasing the risk of complications or the overall outcome.

Preoperative evaluation and surgery in isolated ventricular septal defects: a 21 year perspective

OBJECTIVE

To study short and long term results after surgical closure of isolated ventricular septal defects (VSDs) from 1976 to 1996, especially in relation to changes in preoperative evaluation during this period.

DESIGN

Retrospective study.

SETTING

Tertiary referral centre for paediatric cardiac care.

PATIENTS

All children under 18 years of age who had corrective surgery for VSD between 1976 and 1996.

MAIN OUTCOME MEASURES

Preoperative evaluation, indications for surgery, diagnostic errors, and early and late results.

RESULTS

A significant decrease in the use of invasive preoperative studies in favour of non-invasive methods was found; from 1976 to 1990, a total of 109/110 patients had preoperative invasive study as compared to 43/167 from 1991 to 1996 (p < 0.001). Pulmonary hypertension in small children, without detailed information on Qp:Qs ratio, as well as small or modest shunts without pulmonary hypertension, were more frequent indications for surgery in recent years. Early mortality after surgery occurred in 10 patients, with a significantly lower mortality rate found between 1991 and 1996 than between 1976 and 1990 (0.6% v 8.2%, p < 0.001). Children with large VSDs experienced perioperative complications significantly less often between 1991 and 1996 than between 1976 and 1990 (16/105 v 28/96, p < 0.05). Diagnostic errors showed a tendency to decrease between the two time periods. No late deaths occurred.

CONCLUSIONS

Significant reductions in early mortality, perioperative complications, and diagnostic mistakes were seen during the study period, even though less invasive diagnostic procedures were being performed.

Ventricular Septal Defect

Ventricular septal defects (VSDs) are the most common congenital heart malformations seen in children. Because spontaneous closure occurs frequently, patients with small VSDs should be followed clinically with no limitations except endocarditis prophylaxis. Surgical closure is recommended for only small defects with significant associated lesions such as aortic regurgitation, aortic valve prolapse, right or left ventricular outflow obstruction, tricuspid regurgitation, left ventricle to right atrial shunt, or recurrent endocarditis. Enlarging left ventricular size or deteriorating left ventricular function would also be an indication for surgical repair. Moderate and large VSDs in infancy often require treatment of congestive heart failure with diuretics, digitalis, and afterload reduction. Surgical closure before 9 months of age is indicated for large VSDs and by 2 years of age for moderate shunts to prevent pulmonary vascular obstructive disease and the consequences of long-standing volume overload. Device closure of VSD is still in the investigational stage but holds promise for treatment of apical or multiple muscular VSDs.