Assessment of patient radiation doses during transcatheter closure of ventricular and atrial septal defects with Amplatzer devices

Abstract

The purpose of this study was to estimate the radiation dose to which children are exposed during cardiac catheterizations for the treatment of ventricular and atrial septal defects. Radiation doses were estimated for 46 children aged 1-18 years. These children were treated for secundum atrial septal defects (ASD group) for perimembranous ventricular septal defects (VSD group) or underwent a routine diagnostic catheterization (diagnostic group). Thermoluminescent dosimeters (TLDs) were attached in locations, representing the lateral entrance dose, the posterior entrance dose, the thyroid dose, and the gonad dose, respectively. A dose area product (DAP) meter was also attached externally on the posterior-anterior (PA) tube to give a direct value in cGy cm(2) for each procedure. The patient's entrance dose from the PA field ranged from 1.5 to 185.0 mGy for all patients, while the lateral entrance dose varied from 0.9 to 204 mGy. Radiation exposure to the thyroid and the gonads was found to vary from 0.4 to 8.3 and 0.1 to 2.1 mGy, respectively. The DAP meter recorded DAP values for the posterior tube, between 46 and 3,700 cGy cm(2). The mean effective dose was found to be 7.7, 16.2, and 33.3 mSv for the diagnostic, the ASD, and the VSD group, respectively. Very strong correlation was found between the DAP values and the entrance radiation dose measured with TLDs. The mean entrance dose received from therapeutic cardiac catheterizations using the Amplatzer devices was found approximately twice the dose received from a diagnostic one. Even for the most complex procedures, the maximum entrance dose was at least 10 times lower than the threshold, associated with skin erythema.

Impact of intracardiac echocardiography on radiation exposure during adult congenital heart disease catheter-based interventions

“…Adult patient radiation doses have been evaluated in different types of cardiovascular interventions: simple diagnostic cardiac and peripheral catheterization [11], stent-grafting of abdominal aortic aneurysms [12], permanent cardiac pacemaker implantation procedures [13], during transcatheter closure of ventricular and atrial septal defects [14]. The advent of new imaging techniques such as the intracardiac echocardiography has the potential to improve safety and effectiveness of a large number of procedures reducing the amount of radiation for patients and operators.…”

Substantial radiation reduction in pediatric and adult congenital heart disease interventions with a novel X-ray imaging technology

“…Even though the long-term risks of fatal malignancy following a single pediatric catheter investigation seems very low, the effect of repetitive exposure is unclear [7], [31]. In general, DAP values measured during pediatric catheterizations show an excellent correlation with the entrance radiation dose and skin doses measured with thermoluminescent dosemeters (TLDs) or can be transferred by calculation models to effective doses and are therefore valid to obtain a real-time measurement of the total amount of radiation used [4], [13], [32], [33], [34], [35]. Similar results are obtained when calculating effective doses from DAP as published by the International Commission on Radiology Protection and measuring the effects on DNA damage [8].…”

“…The mean body weight was 28.7 kg (median 21,0) and the mean fluoro-time 22.3 min (median 16.5 min) [4]. They reported mean DAP doses of 1.071 cGy·cm 2 (median 873 cGy·cm 2 ).…”

“…[1], [2]. While their benefits to the patients are undisputable, all these procedures contribute to high accumulated radiation doses to the patient population [3], [4], [5]. This is particularly relevant for infants and children and even if the long term consequences of this exposure are not well understood and extremely difficult to estimate, there is now for many decades considerable concern about the possible stochastic effects, such as the incidence of solid tumors and leukemia [6], [7], [8], [9], [10], [11].…”

Fast block flow tracking of atrial septal defects in 4D echocardiography

“…A compelling review of image-guided surgical applications can be found in (Peters, 2006). There are two alternatives for minimally invasive ASD closure procedures: one using a catheter-based closure, usually under contrast-enhanced fluoroscopy (Faella et al, 2003;Papadopoulou et al, 2005); and another using rigid instruments through the chest wall (Suematsu et al, 2004), demonstrated in animals. Although clinically available, the catheter-based procedure has major disadvantages: it can only be used on a fraction of ASD (Patel et al, 2006), it excludes procedures on small children (Paragios., 2003), and it is generally performed under a high Xray dose (Papademetris et al, 2003).…”