Influence of PFO Anatomy on Successful Transcatheter Closure

Effects of morphological characteristics of patent foramen ovale by transesophageal echocardiography on minimalist transcatheter closure in southern China

OBJECTIVES

Transcatheter closure has become one of the main treatment methods for patent foramen ovale (PFO). However, the population in southern China is generally thin and the size of PFO is small, so the application of minimalist surgery is challenging. This study aimed to analyze the morphological characteristics of PFOs in southern China by transesophageal echocardiography (TEE), and to explore the influence on minimalist transcatheter closure.

METHODS

About 110 patients with PFO closure in our hospital were selected. All cases were examined by TEE including the PFO size, length, septum secundum thickness, color characteristic and surrounding structures, and morphologically classified. During the operation, the procedure time, number of times for the guidewire attempting to pass the interatrial septum and the success rate of simply using J guidewire to cross the interatrial septum were recorded.

RESULTS

About 110 cases of PFO were classified into two categories and four subtypes, including 55 cases with Uniform Channel Type (UCT, 50.0%), 16 cases with Irregular Channel Type (ICT, 14.6%), 15 cases with Right Funnel Type (RFT, 13.6%), and 24 cases with Left Funnel Type (LFT, 21.8%). According to the complexity of the procedure, they were divided into simple procedure (n = 73) and complex procedure (n = 37). Multivariate logistic regression showed that the anatomical types of PFO, the tunnel entrance size, and the tunnel entrance size <2 mm were independent factors affecting the complexity of procedure [OR = 2.819, 95% CI (1.124, 7.066), p = .027; OR = .027, 95% CI (.004, .208), p = .001; OR = 4.715, 95% CI (1.028, 21.619), p = .046]. With ICT and LFT groups, the procedure duration was relatively long (p < .001), number of times for the guidewire attempting to pass the interatrial septum was significantly increased (p < .001), and the success rate of simply using J guidewire to cross the interatrial septum was relatively low (p < .001).

CONCLUSIONS

The PFO size in southern China was relatively small and characterized by large tunnel tension. It was concluded that TEE could clearly show the morphological characteristics of PFO, which could provide guidance for making more reasonable surgical plans in clinical practice, shorten the procedure time and improve the success rate of PFO closure.

Importance of Persistent Right-to-Left Shunt After Patent Foramen Ovale Closure in Cryptogenic Stroke Patients

Percutaneous closure of patent foramen ovale (PFO) is widely performed to prevent recurrent stroke or transient ischemic attack in patients with cryptogenic stroke. However, the influence of different degrees of right-to-left shunting (RLS) has rarely been reported. We retrospectively evaluated the cases of 268 patients with cryptogenic stroke who underwent PFO closure at our hospital from April 2012 through April 2015. In accordance with RLS severity, we divided the patients into 2 groups: persistent RLS during normal breathing and the Valsalva maneuver (n=112) and RLS only during the Valsalva maneuver (n=156). Baseline characteristics, morphologic features, and procedural and follow-up data were reviewed. The primary endpoint was stroke or transient ischemic attack. More patients in the persistent group had multiple or bilateral ischemic lesions, as well as a larger median PFO diameter (2.5 mm [range, 1.8-3.9 mm]) than did patients in the Valsalva maneuver group (1.3 mm [range, 0.9-1.9 mm]) (P <0.001). Atrial septal aneurysm was more frequent in the persistent group: 25 patients (22.3%) compared with 18 (11.5%) (P=0.018). Three patients in the persistent group had residual shunting. The annual risk of recurrent ischemic stroke was similar between groups: 0.298% (persistent) and 0.214% (Valsalva maneuver). Our findings suggest that patients with persistent RLS have more numerous severe ischemic lesions, larger PFOs, and a higher incidence of atrial septal aneurysm than do those without. Although our persistent group had a greater risk of residual shunting after PFO closure, recurrence of ischemic events did not differ significantly from that in the Valsalva maneuver group.

A Case of Complex PFO Leading to Ischemic Stroke: A Practical Clinical Pearl for Neurohospitalists

Patent foramen ovale (PFO) has been proposed as a mechanism for cardioembolic stroke, especially in younger patient populations. Complex PFOs, with tunnel lengths exceeding 8 mm, lead to a higher risk of neurological sequelae than simple PFOs and may also be harder to detect with transthoracic echocardiography (TTE). In this article, we present a 29-year-old woman who, after polypharmacy overdose, developed deep venous thrombosis and multiple pulmonary emboli (PE) and subsequent cardioembolic stroke. Initial TTE showed intact interatrial septum with late appearance of agitated saline in the left atrium after the seventh cardiac cycle. Subsequent transesophageal echocardiography, after treatment of PE with an intravenous thrombolytic (alteplase) and anticoagulation with heparin, showed a complex PFO with a 19-mm overlap of the septum primum and secundum without active flow. It is suggested that this PFO allowed for flow only in the situation of elevated right heart strain with PE, causing cardioembolic stroke and detection of agitated saline in the left atrium on TTE. However, under normal physiological situations, which resumed after treatment of PE with alteplase and heparin, the PFO did not allow for flow. This case demonstrates the potential importance of recognition of complex PFOs in diagnosis and management of cardioembolic stroke.