Effect of right ventricular volume overload on left ventricular diastolic function in patients with atrial septal defect

Outcomes in Patients with Pulmonary Arterial Hypertension Underwent Transcatheter Closure of an Atrial Septal Defect

Pulmonary arterial hypertension (PAH) related to an atrial septal defect (ASD) poses a challenge to transcatheter closure of an ASD (tcASD). We aimed to determine the predictors for remaining PAH (rPAH) post-tcASD. This retrospective study was conducted at a single tertiary university hospital. Adult patients with an ASD and PAH were divided into three groups according to pulmonary vascular resistance (PVR). Normalization of pulmonary atrial systolic pressure (PASP) was defined as an estimated right ventricular systolic pressure < 40 mmHg and was determined using transthoracic echocardiography. Among 119 patients, 80% showed PAH normalization post-tcASD. Normalization of PAH post-tcASD was observed in 100%, 56.2%, and 28.6% of patients in mild, moderate, and severe PVR groups, respectively. The patients’ New York Heart Association functional class improved. Multivariate logistic regression analysis showed that age and high PVR were significant risk factors for rPAH. A receiving operator curve analysis showed a PASP cutoff value > 67.5 mmHg to be predictive of rPAH post-tcASD, with an area under the curve value of 0.944 (sensitivity, 0.922; specificity 0.933). Most patients, including moderate-to-severe PAH patients, improved hemodynamically and clinically with tcASD. Since patients with severe PAH are at a risk of rPAH, tcASD should be performed by selecting the patient carefully based on pre-procedure medication, a vasoreactivity test, and a balloon occlusion test.

The changes in biventricular remodelling and function after atrial septal defect device closure and its relation to age of closure

Background

The trans-catheter closure of atrial septal defect (ASD) usually has a rapid impact on biventricular remodelling and functions. Whether the transcatheter closure of ASD at early childhood or at adulthood age would affect the improvement in biventricular dimensions and functions remains an area of active research.

Results

This prospective observational study enrolled 70 subjects (50 ASD cases and 20 control subjects). Tissue Doppler imaging (TDI) and strain (S) were performed for the control group and ASD patients at baseline and at 24 h and 1 month after ASD device closure. The total ASD group was subdivided into two subgroups: group-1—children and adolescent with ASD, who underwent transcatheter closure at age ≤ 19 years; group-2—adult who underwent ASD device closure at age > 19 years old. The right and left ventricular global longitudinal systolic strain (RV/LV-GLS) and RV free wall longitudinal strain (RV free wall LS) showed a significant decline after 24 h of device closure (RVGLS-P = 0.001, LVGLS-P = 0.048, RV free wall LS-P < 0.001). However, after a 1-month follow-up, the LVGLS increased in comparison with 24 h changes after device closure (P = 0.038). The baseline mean value of RV free wall LS of G2 was significantly lower than G1 value (P < 0.001). There was no statistically significant difference between the 2 age subgroups regarding biventricular GLS and RV free wall LS changes after device closure. The changes in LV diastolic function immediately and after 1 month of device closure showed a statistically significant change in e′ and its delta change value in group-2 in comparison with its baseline values and to group-1 delta changes (P = 0.002, P = 0.011, P = 0.019, respectively).

Conclusion

The ASD transcatheter closure reduced biventricular global and RV free wall longitudinal systolic strain within 1 day of intervention and was associated with a short-term improvement in the LV-GLSS after a 1-month duration. The progressive increase in LV preload results in its strain growth and reduction in diastolic function after transcatheter ASD closure. The older age at the time of ASD device closure was associated with a significant decrease in the RV free wall LS and septal e′ velocity towards abnormality.

Favorable changes of left ventricular function in the circumferential direction following transcatheter atrial septal defect closure: a strain imaging study

To clarify the impact on left ventricular (LV) function of percutaneous atrial septal defect (ASD) closure in adult patients. Echocardiograms of 46 patients (52 ± 18 years) who underwent ASD closure with a significant left-to-right shunt obtained before and 1 month after the procedure were retrospectively analyzed. Functional parameters were obtained by 2-dimensional speckle-tracking imaging. Global longitudinal strain and strain rate at early diastole (SRe) was calculated from the three standard apical views, while circumferential and radial parameters were calculated from basal, middle, and apical LV short-axis views. Along with a diminished right ventricular (RV) volume, the LV volume and ejection fraction increased (end-diastolic volume: 61 ± 12 to 76 ± 15 mL, p < 0.001; and 63% ± 4 to 64% ± 4% p = 0.03; respectively). Both global strain and SRe was augmented only in the circumferential direction (- 16.2% ± 2.9% to - 19.8% ± 2.8%; and 1.07 ± 0.29 to 1.34 ± 0.28 s^-1, both p < 0.001). Augmentation of circumferential SRe correlated with both the changes in and the pre-procedural value of diastolic LV eccentricity index (r = - 0.57, p < 0.001; and r = 0.37, p = 0.01; respectively), a morphological parameter of RV volume overload. Following ASD closure in adults, both LV systolic and diastolic function could favorably change in the circumferential direction, and the degree of diastolic functional change is associated with RV volume overload, i.e., severity of ventricular interdependence.

Assessment of ventricular function in patients of atrial septal defect by strain imaging before and after correction

Background:

Atrial septal defect (ASD) is a common congenital heart disease associated with volume overload of Right ventricle (RV) with variable effect on Left ventricle (LV). Two-dimensional (2D) Strain analysis is a new tool for objective analysis of myocardial function. This prospective study evaluated the systolic function of right and left ventricle by conventional 2D echo and strain echo and measured changes in cardiac hemodynamics that occurred in patients of ASD before and after correction.

Patients and Methods:

2D echo and strain analysis of each patient before and at 48 hrs, 3 months and 6 months after correction was performed. Routine 2D echo parameters and global longitudinal strain of both ventricles were measured.

Result:

Improvement in LV ejection fraction (P = 0.0001) and myocardial performance index (MPI) (P < 0.0001) occurred at the end of 6 months, whereas decrease in RV MPI (P < 0.0001) and tricuspid annular plane systolic excursion (P < 0.0001) became statistically significant after 3 months of ASD correction. In comparison to conventional 2D echo, global longitudinal strain of RV decreased significantly only after 48 hours of ASD correction while there was no improvement in left ventricular global longitudinal strain after 6 month of correction.

Conclusion:

There was improvement in RV function with subtle change in LV function by strain imaging and most of these changes were completed within 6 months of ASD correction and nearly correlated with conventional 2DEchocardiography.

Pathophysiology and natural history of atrial septal defect

Atrial septal defects are among the third most common types of congenital heart disease. This group of malformations includes several types of atrial communications allowing shunting of blood between the systemic and the pulmonary circulations. The nature of shunting across the defect in patients with atrial septal defect is of particular interest. Understanding the underlying mechanisms of interatrial shunts and their natural history will help selecting the best timing for closure, before irreversible cardiac and pulmonary injury occur. This review describes the different pathophysiologic mechanisms involved in the direction and magnitude of blood flow through atrial septal defects. The natural history of an individual born with an isolated atrial septal defect is then discussed, including the impact of a longstanding shunt on survival.

Alterations in ventricular pumping in patients with atrial septal defect at rest, during dobutamine stress and after defect closure

BACKGROUND

Regional ventricular pumping mechanisms in patients with volume-loaded right ventricles (RV) are altered, but the cause is unknown. The aim was to determine whether these changes in ventricular pumping mechanisms are influenced by the RV dilatation itself or the aetiology behind it.

METHODS

Seventeen patients with atrial septal defects (ASD) and 10 healthy controls underwent cardiovascular magnetic resonance (CMR) at rest and during dobutamine/atropine stress. Sixteen patients underwent transcutaneous ASD closure. Follow-up CMR at rest was performed the following day. Thirty patients with RV overload due to pulmonary regurgitation (PR) underwent CMR at rest. Cine images were used to measure left ventricular (LV) and RV volumes as well as septal, longitudinal and lateral contributions to LV and RV stroke volume (SV).

RESULTS

At rest, septal contribution to LVSV was lower in ASD patients than controls (-1% versus 7%, P<0·05), but there was no difference in longitudinal or lateral contribution to SV. Patients with PR had lower longitudinal contribution to RV with increased lateral and septal contribution. During dobutamine stress, longitudinal contribution to LV and RVSV decreased and lateral contribution increased for ASD patients and controls. The day after ASD closure, septal contribution to LVSV was 6%, longitudinal contribution had increased for RVSV (P<0·05) and decreased for LVSV (P<0·01).

CONCLUSION

Pumping mechanisms in patients with RV volume overload depend on the aetiology for the RV dilation and not the size of the RV.

IN-SILICO MODELING OF LEFT VENTRICLE TO SIMULATE DILATED CARDIOMYOPATHY AND CF-LVAD SUPPORT

Numerical modeling of the left ventricle dynamics plays an important role in testing different physiological scenarios and treatment techniques before the in vitro and in vivo assessments. However, utilized left ventricle model becomes vital in the simulations because validity of the results depends on the response of the numerical model to the parameter changes and additional sub-models for the applied treatment techniques. In this study, it is aimed to evaluate different numerical left ventricle models describing healthy and failing ventricle dynamics as well as the response of these models under continuous flow left ventricular assist device support. Six different numerical left ventricle models which include time varying elastance and single fiber contraction approaches are selected and applied in combination with a closed loop electric analogue of the circulation to achieve this purpose. The time varying elastace models relate ventricular pressure and volume changes in a simplistic way while the single fiber contraction models combine different scales ranging from protein to organ level. Change of the hemodynamic signals at the organ level for healthy, failing and CF-LVAD supported left ventricle models shows functionality of these models and helps to understand usability of them for different purposes.

Pulmonary edema following transcatheter closure of atrial septal defect

We describe an incident of development of acute pulmonary edema after the device closure of a secundum atrial septal defect in a 52-year-old lady, which was treated with inotropes, diuretics and artificial ventilation. Possibility of acute left ventricular dysfunction should be considered after the defect closure in the middle-aged patients as the left ventricular compliance may be reduced due to increased elastic stiffness and diastolic dysfunction. Baseline left atrial pressure may be > 10 mmHg in these patients. Associated risk factors for the left ventricular dysfunction are a large Qp:Qs ratio, systemic hypertension, severe pulmonary hypertension and paroxysmal atrial fibrillation.

Left ventricular function in adult patients with atrial septal defect: implication for development of heart failure after transcatheter closure

Despite advances in device closure for atrial septal defect (ASD), post-closure heart failure observed in adult patients remains a clinical problem. Although right heart volume overload is the fundamental pathophysiology in ASD, the post-closure heart failure characterized by acute pulmonary congestion is likely because of age-related left ventricular diastolic dysfunction, which is manifested by acute volume loading with ASD closure. Aging also appears to play important roles in the pathophysiology of heart failure through several mechanisms other than diastolic dysfunction, including ventricular systolic and vascular stiffening and increased incidence of comorbidities that significantly affect cardiovascular function. Recent studies suggested that accurate assessment of preclosure diastolic function, such as test ASD occlusion, may help identify high-risk patients for post-closure heart failure. Anti-heart failure therapy before device closure or the use of fenestrated device appears to be effective in preventing post-closure heart failure in the high-risk patients. However, the long-term outcome of such patients remains to be elucidated. Future studies are warranted to construct an algorithm to identify and treat patients at high risk for heart failure after device closure of ASD.

Atrial Septal Defect and Atrial Fibrillation: The Known and Unknown

Atrial fibrillation (AF) is a common complication in patients with atrial septal defects (ASDs). The link between AF and ASD is fairly complex and entails modifications in electrophysiologic, contractile and structural properties, at the cellular and tissue level, of both atria, mainly due to chronic atrial stretch and dilation. Surgical repair or percutaneous closure of ASDs are equally effective in reducing mortality and symptoms but limited in preventing or curbing AF, unless combined with an arrhythmia-specific procedure. Transesophageal echocardiography (TEE) and intracardiac echocardiography (ICE) have improved the safety and success of the above procedures. Finally, clearer understanding of the pathophysiology of AF in patients with ASD (and CHF, in general) has led to target-specific advances in medical management.

Improvement of biventricular function after transcatheter closure of atrial septal defect: a case report

We report a 17-year-old man presented with palpitation. Echocardiography demonstrated secundum atrial septal defect (ASD) with marked right sided dilatation, indicating significant left to right intracardiac shunting. Cardiac magnetic resonance imaging performed 3 months after transcatheter ASD closure demonstrated marked improvement in biventricular systolic function.

Improvements in cardiac form and function after transcatheter closure of secundum atrial septal defects

OBJECTIVES

We set out to study the effect of transcatheter closure of atrial septal defect (ASD) on right ventricular (RV) and left ventricular (LV) function assessed by myocardial performance index (MPI), as well as left atrial (LA) volumes.

BACKGROUND

The hemodynamic response to the closure of ASD is well-documented in surgically treated patients. However, few studies have documented echocardiographic evaluation of ventricular function in patients undergoing transcatheter closure of ASDs.

METHODS

Pre- and post-ASD device closure echocardiograms of 25 consecutive patients were retrospectively reviewed. Measurements of RV and LV MPI and LA volumes were made.

RESULTS

Twenty-five patients with an average age of 45.5 +/- 16.3 years underwent transcatheter closure of ASD. There was statistically significant improvement in RV MPI (0.35 to 0.28, p = 0.004), LV MPI (0.37 to 0.31, p = 0.04), and LA volume index (25.7 to 21.8 ml/m(2), p < 0.001) after closure of ASD.

CONCLUSIONS

Device closure of ASDs leads to improvement of both RV and LV function as well as reduction in LA volume. These hemodynamic improvements provide insights into the symptomatic benefits gained in closure of ASDs using the transcatheter approach.

Transcatheter closure of atrial septal defect preserves right ventricular function

OBJECTIVES

To determine the effects of atrial septal defects (ASD) and their closure on systolic and diastolic right and left ventricular function; and by comparing surgical closure with transcatheter device closure, to establish differences attributable to cardiopulmonary bypass.

DESIGN

Cross sectionally guided M mode echocardiographic ventricular long axis function was measured prospectively before and within one week after ASD closure by device in 17 patients and by surgery in 12 patients, and compared with 18 normal subjects.

RESULTS

All indices of right ventricular function were impaired after surgery: mean total excursion, -1.89 cm (95% confidence interval (CI), -2.18 to -1.59); peak shortening rate, -9.09 cm/s (-10.82 to -7.35); peak lengthening rate, -9.26 cm/s (-11.09 to -7.43). Total excursion and peak lengthening rate were preserved after device closure, at -0.12 cm (-0.28 to 0.05) and 0.01 cm/s (-2.29 to 2.31), respectively. Left ventricular free wall function was unchanged after closure by either method, while all septal measurements were reduced after closure by either method (changes ranging from -3.51 to -0.32; 95% CI ranging from -4.90 to -0.13).

CONCLUSIONS

Left ventricular free wall function is unaffected by ASD closure, whereas septal function is impaired, irrespective of the method of closure. Right ventricular function, both systolic and diastolic, is impaired by cardiopulmonary bypass but preserved after device closure. These findings support the transcatheter approach to ASD closure in anatomically suitable defects.