Page 19 - Journal of Structural Heart Disease Volume 4, Issue 3

Original Scienti c Article
76
Figure 2. ROC curve for the ratio of the Device Waist Diameter to Patient’s Length. Area under the curve was 0.72 (95% con dence interval 1.78-29.85 , p = 0.006). The circle represents the optimal cut-o values which give the best sensitivity and speci city. ROC = Receiver-operating characteristic.
The results show that shorter septal rim towards superior vena cava and larger closure device waist diameter in relation to body height were predictors of procedure prolongation during percutaneous transcatheter closure of the atrial septal defect. The best cut-o values for these predictors were 12 mm and 0.13, respectively. Monovariate analysis revealed that the ratio of device waist diameter to left atrium (LA) dimensions may also predict procedure prolon- gation.
The ndings support the common knowledge that the complexity of any intervention is increased by small patient size [17]. The relations of device waist diameter to weight and length are signi cant predic- tors. It has been reported that patient weight can be used as a guide for device size selection. The criteria proposed that device diameter (in mm) to weight (in kg) ratio should be less < 1.5 [18]. In the current study, multivariate analysis showed that the device waist di- ameter in relation to the height of the patients seems to be statistically more important than its relation to weight. Ko et al. reported that a larger defect, smaller
Figure 3. ROC curve for the ratio of the Device Waist Diame- ter to LA Anterior-posterior Length, LA coronal length, LA lateral length. Areas under the curve were 0.65 (95% CI = 1 - 7.26, p = 0.046), 0.70 (95% CI =1.27 - 9.62, p = 0.013), and 0.689 (95% CI = 1.37 - 10.45, p = 0.008) respectively. ROC = Receiver-operating characteristic; LA = Left atrium; CI = Con dence Interval.
posterior-superior rim, smaller retro-aortic rim and smaller ratios of the LA dimensions to the device size predicted the need to apply modi ed methods for ASD device closure, leading to prolongation of the procedure. Based on their results, they speculated that the relationship between device size and left atri- al anteroposterior dimension is the most important one [8]. It is interesting that though we de ned pro- longed procedure di erently (length of deployment time > ten minutes), we came to a similar result. The relationship between the device waist size and the left atrial anteroposterior dimension seems to be an important variable; a ratio > 2:3 predicted an increase in the complexity and duration of the intervention.
The most common site for erosions after ASD tran- scatheter closure is the free wall of the left atrium or the posterior aspect of the aorta [19], which repre- sent the two boundaries of the anteroposterior axis of the left atrium. This could indicate that oversizing the device in relation to the left atrial anteroposterior diameter may increase the risk of procedure di cul- ties and prolongation.
Journal of Structural Heart Disease, June 2018
Volume 4, Issue 3:69-78