One-stop shop assessment for atrial septal defect closure using 256-slice coronary CT angiography

Transcatheter Closure of Atrial and Ventricular Septal Defects: JACC Focus Seminar

The field of congenital interventional cardiology has experienced tremendous growth in recent years. Beginning with the development of early devices for transcatheter closure of septal defects in the 1970s and 1980s, such technologies have evolved to become a mainstay of treatment for many atrial septal defects (ASDs) and ventricular septal defects (VSDs). Percutaneous device closure is now the preferred approach for the majority of secundum ASDs. It is also a viable treatment option for selected VSDs, though limitations still exist. In this review, the authors describe the current state of transcatheter closure of ASDs and VSDs in children and adults, including patient selection, procedural approach, and outcomes. Potential areas for future evolution and innovation are also discussed.

Role of MDCT in evaluating prothesis size prior to percutaneous transcatheter closure of ostium secundum atrial septal defect

To investigate the feasibility and accuracy of cardiac multidetector computed tomography (MDCT) prosthesis sizing prior to ostium secundum atrial septal defect (ASD) percutaneous closure. Seventy consecutive patients were included in this retrospective bicentric study between May 2012 and June 2018. All underwent cardiac MDCT (primarily performed to rule out abnormal venous pulmonary return and coronary anomaly) and transesophageal echocardiography (TEE) before transcatheter closure: dimensions of the defect and peripheral rims were measured. Measurements of the defect obtained at TEE and MDCT were compared to prosthesis size. Our primary objective was the comparison of ASD maximal diameter obtained at MDCT (CT-Dmax) to prosthesis size. Intraclass correlation coefficient (ICC), Bland Altman plots and linear regression were calculated. Intra- and inter-observer agreements were calculated for MDCT defect measurements. Forty-three patients were finally included for defect measurements: 17 patients did not undergo transcatheter closure, and 10 had incomplete data. For CT-Dmax, ICC was 0.88 (CI 95% = [0.78-0.93]; p = 0.06); mean difference was - 0.8 ± 5.7 mm; regression linear equation was 0.9 × + 3.2 (p < 0.001). For maximal diameter at TEE versus prosthesis size, ICC was 0.46 (CI 95% = [0.21-0.61]; p = 0.003); mean difference was-6.0 ± 8.2 mm; regression linear equation was 0.91 × + 7.6 (p < 0.001). Intra- and inter-observer agreement for CT-Dmax were 0.97 (CI 95% = [0.95-0.98]) and 0.86 (CI 95% = [0.73-0.93]) respectively. MDCT is a reliable tool for sizing the defect of ostium secundum ASD, making it a complement or even an alternative to pre-procedural TEE.

CT evaluation of unrepaired/incidental congenital cardiovascular diseases in adults

Congenital heart disease (CHD) affects approximately one million people in the USA with the number increasing by 5% each year. Patients are usually both diagnosed and treated in infancy, however many of them may have subclinical CHD that remains undiagnosed until late adulthood. Patients with complex CHD tend to be symptomatic and are diagnosed at a younger age than those with a single defect. CHDs can be divided into three categories, including cardiac, great vessels and coronary artery anomalies. Recent advances in computed tomography (CT) technology with faster acquisition time and improved spatial resolution allow for detailed evaluation of cardiac morphology and function. The concomitant increased utilization of CT has simultaneously led to more sensitive detection and more thorough diagnosis of CHD. Recognition of and understanding the imaging attributes specific to each anomaly is important for radiologists in order to make a correct and definite diagnosis. This article reviews the spectrum of CHDs, which persist into adulthood that may be encountered by radiologists on CT.

Assessment of long-term cardiac adaptation in adult patients with type II atrial septal defect : A cardiovascular magnetic resonance (CMR) study

OBJECTIVES

In type II atrial septal defect (ASD) patients, the left-to-right (LR) shunt causes adaptation of the heart and circulation. The study objective was to evaluate with cardiovascular magnetic resonance imaging (CMR) the impact of LR shunt on left (LV) and right ventricular (RV) volumes, function, and myocardial strain.

METHODS

Thirty-five patients (42 ± 17 years, 17 male) were compared to a control group (n = 40). Cine imaging was used to calculate ventricular volumes and ejection fraction (EF), global longitudinal (GLS) and circumferential strain (GCS), and longitudinal free wall (FWS) and interventricular septal (IVS) strain. Phase-contrast imaging was used to calculate pulmonary flow to systemic flow ratio (Qp/Qs).

RESULTS

The LR shunt (Qp/Qs 2.2 ± 0.6) resulted in larger RV end-diastolic volume (EDVi) (152 ± 42 vs 82 ± 11 ml/m²), lower LV EDVi (72 ± 16 vs 83 ± 9 ml/m²⁾, and higher RV/LV EDVi ratio (2.2 ± 0.5 vs 1.0 ± 0.1) than controls (all p < 0.001). Functionally, stroke volumes were larger in RV and lower in LV (both p < 0.001) with a strong trend toward lower RV EF in patients (p = 0.08). The LR shunt negatively impacted RV GLS (p = 0.03) but not RV GCS. Longitudinal IVS but not RV FWS were significantly lower in patients, i.e., p < 0.001, of longitudinal IVS. Shunt severity correlated with RV size and stroke volume, right atrial size, and pulmonary trunk diameter (all p < 0.001), but not with functional nor strain parameters.

CONCLUSION

Long-term cardiac adaptation in ASD patients, with RV overfilling and LV underfilling, has a negative impact on systolic RV performance, a phenomenon which likely can be attributed to longitudinal dysfunction of the interventricular septum.

KEY POINTS

• An LR shunt in type II ASD patients causes cardiac remodeling characterized by RV overfilling and conversely underfilling of the left ventricle. • At the long term, there is evidence of systolic dysfunction of the right ventricle in this group of patients. • Septal dysfunction underlies the observed impairment in RV function.

Transcatheter Closure of Atrial Septal Defects with Cardiac Computed Tomography Sizing: Eight-Year Single-Center Practice

INTRODUCTION

An accurate evaluation of atrial septal defect (ASD) is important for the success of interventional treatment. Cardiac computed tomography (CT) has unique advantages for ASD assessment, although transesophageal echocardiography (TEE) remains the accepted method.

OBJECTIVE

This study aimed to evaluate the safety and feasibility of transcatheter closure of ASD with cardiac CT sizing but without TEE measurement.

METHODS

Among 134 patients undergoing transcatheter closure, 13 underwent TEE in addition to a cardiac CT examination, and 121 underwent only cardiac CT. Propensity score matching was used to analyze the outcomes of the groups treated with (group 1) or without (group 2) TEE examinations. The success rate and complications among the 121 ASD patients with only cardiac CT sizing were recorded and analyzed. The maximal diameters of the defects remeasured on CT images were compared to the echocardiography results and correlated with the device size by Student t test and Pearson's linear regression analysis, respectively.

RESULTS

No significant differences (p > 0.05) were found between groups 1 and 2 in the success rate, complications, or ratio of the device size to the maximum diameter of the defect measured by cardiac CT. In group 1, the maximum diameters of the ASD derived from cardiac CT and TEE were comparable (22.08 ± 9.68 vs. 21.50 ± 10.24; p = 0.351). The success rate among the 121 patients who underwent transcatheter closure with only cardiac CT sizing was 99.2%; however, within 1 month of follow-up, 2 patients had arrhythmia, 1 patient had residual shunting, 1 patient had an infection, and 1 patient had a hematoma, but all patients recovered within a short time.

CONCLUSIONS

Cardiac CT seems to be comparable to TEE in the assessment of ASD, and transcatheter closure of ASD based on CT sizing alone is safe and feasible.

Evaluation of atrial septal defects with 4D flow MRI-multilevel and inter-reader reproducibility for quantification of shunt severity

Purpose

With the hypothesis that 4D flow can be used in evaluation of cardiac shunts, we seek to evaluate the multilevel and interreader reproducibility of measurements of the blood flow, shunt fraction and shunt volume in patients with atrial septum defect (ASD) in practice at multiple clinical sites.

Materials and methods

Four-dimensional flow MRI examinations were performed at four institutions across Europe and the US. Twenty-nine patients (mean age, 43 years; 11 male) were included in the study. Flow measurements were performed at three levels (valve, main artery and periphery) in both the pulmonary and systemic circulation by two independent readers and compared against stroke volumes from 4D flow anatomic data. Further, the shunt ratio (Q_p/Q_s) was calculated. Additionally, shunt volume was quantified at the atrial level by tracking the atrial septum.

Results

Measurements of the pulmonary blood flow at multiple levels correlate well whether measuring at the valve, main pulmonary artery or branch pulmonary arteries (r = 0.885–0.886). Measurements of the systemic blood flow show excellent correlation, whether measuring at the valve, ascending aorta or sum of flow from the superior vena cava (SVC) and descending aorta (r = 0.974–0.991). Intraclass agreement between the two observers for the flow measurements varies between 0.96 and 0.99. Compared with stroke volume, pulmonic flow is underestimated with 0.26 l/min at the main pulmonary artery level, and systemic flow is overestimated with 0.16 l/min at the ascending aorta level. Direct measurements of ASD flow are feasible in 20 of 29 (69%) patients.

Conclusion

Blood flow and shunt quantification measured at multiple levels and performed by different readers are reproducible and consistent with 4D flow MRI.

Electronic supplementary material

The online version of this article (10.1007/s10334-018-0702-z) contains supplementary material, which is available to authorized users.