Acta Cardiol Sin 2016;32:731-737 Brief Report doi: 10.6515/ACS20160205A Echocardiographic Follow-Up of Patent Foramen Ovale and the Factors Affecting Spontaneous Closure Ali Yildirim,1 Alperen Aydin,2 Tevfik Demir,1 Fatma Aydin,2 Birsen Ucar1 and Zubeyir Kilic1 Background: The aim of the present study was to evaluate the echocardiographic follow-up of patent foramen ovale, which is considered a potential etiological factor in various diseases, and to determine the factors affecting spontaneous closure. Methods: Between January 2000 and June 2012, records of 918 patients with patent foramen ovale were retrospectively reviewed. Patency of less than 3 mm around the fossa ovalis is called patent foramen ovale. Patients with cyanotic congenital heart diseases, severe heart valve disorders and severe hemodynamic left to right shunts were excluded from the study. The patients were divided into three groups based on age; 1 day-1 monthingroup1,1month-12monthsingroup2,andmorethan12monthsingroup3. Results: Of the 918 patients, 564 (61.4%) had spontaneous closure, 328 (35.8%) had patent foramen ovale continued, 15 (1.6%) patients had patent foramen ovale enlarged to 3-5 mm, 6 patients were enlarged to 5-8 mm, and in one patient patent foramen ovale reached to more than 8 mm size. Defect was spontaneously closed in 65.9% of the patients in group 1, 66.7% of the patients in group 2, and 52.3% of the patients in group 3. There was a negative correlation between the age of diagnosis and spontaneous closure (p < 0.05). Gender, prematurity and coexisting malformations such as patent ductus arteriosus and atrial septal aneurysm did not have any effect on spontaneous closure of patent foramen ovale (p > 0.05). However, ventricular septal defect and spontaneous closure of patent foramen ovale had a positive correlation (p < 0.01). No correlation was noted between the existence of atrial septal aneurysm, prematurity, and maturity of the patients. Conclusions: The present study demonstrated that spontaneous closure rate of patent foramen ovale is high. Furthermore, a positive correlation was found between spontaneous closure of patent foramen ovale with early diagnosis and small defect size. Key Words: Echocardiography · Patent foramen ovale · Spontaneus closure INTRODUCTION structure to provide blood flow from the right to the left atrium during the intrauterine period. Patency of this Foramen ovale is an oblique canal situated between embryonic remnant beyond labor is called patent fora- the thin, membranous flexible flap-like septum premium men ovale.1 The most common congenital anomaly that and septum secundum, a thicker and harder muscular is seen with patent foramen ovale (PFO) is atrial septal aneurism.2 However, a full 75% of PFOs close spontane- ously prior to the second year of life. To date, few studies have been conducted focusing Received: April 27, 2015 Accepted: February 5, 2016 1Department of Pediatric; 2Department of Pediatric Cardiology, on echocardiographic follow-up of PFO. Previous studies Medical Faculty, Eskisehir Osmangazi University, Eskisehir, Turkey. have shown that a high percentage of PFOs close during Address correspondence and reprint requests to: Dr. Ali Yildirim, the first year of life.3,4 The frequency of PFO diminishes Eskisehir Osmangazi Üniversitesi, Tòp Fakultesi, Pediatrik Kardiyoloji Bilim Dalò, 26480, Eskisehir, Turkey. Tel: 9 0 530 882 2319; Fax: 9 0 as patient age increases, but the dimension can in- 222 239 2979/7440; E-mail: [email protected] crease.5 731 Acta Cardiol Sin 2016;32:731-737 Ali Yildirim et al. Theaimofthepresentstudywastoevaluatethe demonstrated with color flow in the 2-dimensional views echocardiographic follow-up of PFO, which is considered of the fossa ovalis without drop-out, or when a tiny as a potential etiological factor in various diseases, and flap-like septum primium was detected in the left atrium to determine the factors affecting spontaneous closure. and the septum secundum was seen in the right atrium in the presence of canal-type defect. In an analogous study by Radzik et al., patency of less than 3 mm around METHODS AND MATERIALS the fossa ovalis is called PFO if it is more than 3 mm, and wasconsideredtobeanatrialseptaldefect.6 Clear The records of 918 patients with PFO (age range is 1 echocardiographic images can be obtained in pediatric day-170 months) who presented to the pediatric car- populations where a diagnosis of PFO can then be readily diology department between January 2000 and June made. However, difficulty often arises in adolescents 2012 were reviewed. Patients who were followed for at and obese patients, where after transesophageal echo- least 6 months with two echocardiographic evaluations cardiography can be utilized. Additionally, transeso- were included in our study. The “patient information phageal echocardiography was performed especially in form” was used to record age, weight, underlying car- older children with a suspected defect in the 2-dimen- diac and non-cardiac diseases, gestational ages, reason sional transthoracic echocardiographic imaging where of presentation to the hospital and echocardiographic noflowcouldbedemonstratedinthecolorflowexami- evaluations. Consent for the study protocol was obtained nation. For doubtful cases, the septal closure was deter- from the ethics committee of Eskisehir Osmangazi Uni- mined using contrast studies with agitated 5% dextrose. versity Medical School. PFO were observed from the subcostal view of the four- A review of the existing research indicated that there chamber and sagittal planes (Figure 1). Transesophageal is no definitive diagnostic criteria for both PFO and atrial echocardiography was performed in 84 patients with septal defect (ASD), and it is difficult to differentiate suspected PFO who did not have a diagnostic trans- these two lesions.6-11 A diagnosis of patent foramen thoracic echocardiography. Also, a contrast-enhanced ovale was confirmed when the presence of a shunt was echocardiography was performed on 16 patients in whom A B CD Figure 1. Echocardiographic view of patent foramen ovale. Acta Cardiol Sin 2016;32:731-737 732 Echocardiographic Evaluation of Foramen Ovale definitive findings could not be obtained regarding the tive data was expressed as n, mean and standard error shunt. (standard error of mean, SEM); qualitative data were ex- Patients with cyanotic congenital heart diseases, se- pressed as n, median, minimum and maximum values. In vere heart valve disorders and severe hemodynamic comparing the two groups, the t-test was used for data left-to-right shunts were not included in the study. In with normal distribution, and the Mann-Whitney U test cyanotic cardiac disease, severe valvular lesions and was performed for data with non-normally distributed hemodynamically significant left-to-right shunt lesions variables. To demonstrate association between vari- (cardiac failure requiring treatment, pulmonary hyper- ables,Pearson’stestwasperformedondatawithnor- tension, or lesions associated with significant dilation in mal distribution and Spearman’s correlation test for the the left ventricle and left atrium and increased pressure) data with non-normal distribution. Chi-square test was could prevent the closure of PFO or could result in the applied to categorical data sets. The relation between opening of an already closed lesion, by causing signifi- these parameters was determined utilizing logistic re- cantpressureelevationintherightorleftatriumde- gression analysis. A p value less than 0.05 was con- pending on the type of lesion. Therefore, these lesions sidered as significant. were excluded from the study. Patients with large (ratio of defect diameter to annulus diameter was 50% or more) and medium ventricular septal defect (VSD) (ratio RESULTS of defect annulus to aortic annulus diameter was be- tween 33-50% and with left heart enlargement) and A total of 918 patients were included in the study. large patent ductus arteriosus (PDA) (left heart enlarge- Of these, 525 (57.3%) were male and 392 were (42.7%) ment) were excluded from the study. were female, with a median age of 3 months (1 day-170 The patients were divided into three groups based months). When diagnosis was classified based on age, on age, namely: 1 day-1 month in group 1, 1 month-12 369 (40.2%) of the patients were in group 1 (1 day £ 1 months in group 2, and more than 12 months in group month), 246 (26%) were in group 2 (> 1 month-£ 12 3. months) and 303 were (32.9%) in group 3 (> 12 months). The mean follow-up time for these patients was 12 Echocardiographic evaluation months (6 months-122 months). All of the echocardiographic assessments were per- Of these patients, 564 (61.4%) had spontaneous clo- formed by three different pediatric cardiologist using sure, 328 (35.8%) had PFO continued, 15 (1.6%) patients the Hewlett Packard Sonos (Model 5500) and 2-4 MHz hadPFOenlargedto3-5mm,6patientshadPFOen- and 4-8 MHz broadband probes or Vivid I with the 4-12 larged to 5-8 mm, and one (0.1%) patient PFO expanded mHz probes. togreaterthan8mminsize. The diameter of PFO and interatrial septal length Defect was spontaneously closed in 61.4% of the pa- wasmeasuredinatotalof15randomlyselectedPFO tients in group 1, 66.7% of the patients in group 2 and patients between 1 and 10 years of age, where the in- 52.3% of the patients in group 3. There was a negative traobserver and interobserver variability was tested correlation between the diagnosis age and spontaneous using Pearson’s correlation analysis. In these randomly closure (p < 0.05). Echocardiographic progression of dia- selected 15 patients, the intraobserver variability for meter of the defect based on the age groups was shown PFO diameter and interatrial septal length were r = 0.89 in Table 1. and r = 0.91, respectively. The corresponding figures for Of the patients, 85 (9.3%) had VSD, 62 (6.8%) had interobserver variability were r = 0.86 and r = 0.78, re- atrial septal aneurysm and 59 (6.4%) had PDA. Gender, spectively. prematurity and coexisting malformations such as PDA and atrial septal aneurysm did not have any effect on Statistical analysis spontaneous closure of PFO (p > 0.05).