Transcatheter patent foramen ovale closure in spite of interatrial septum hypertrophy or lipomatosis: a case series

Lipomatous Atrial Septal Hypertrophy, an Unexpected Giant Interatrial Mass: A Case Report and Literature Review

Lipomatous atrial septal hypertrophy (LASH) is a histological cardiac benign lesion finding with high prevalence in healthy population, usually detected during imaging procedures for other indications. Nevertheless, it could become clinically significant if it compromises venous return and diastolic left ventricular filling, up to becoming an anatomical substrate for atrial tachyarrhythmias. We present a case of LASH diagnosed in a 54-year-old female patient admitted to our emergency department after ground fall and collateral finding of positive blood cultures leading to transesophageal echocardiography. A giant mass involving the interatrial septum was observed, in the absence of primitive neoplasia evidence after performing a total-body computed tomography scan and abdominal echography. No signs or symptoms of pulmonary venous congestion were observed, and no relevant tachyarrhythmias were detected at continuous electrocardiogram monitoring during the hospitalization period.

Lipomatous Atrial Septal Hypertrophy: A Review of Its Anatomy, Pathophysiology, Multimodality Imaging, and Relevance to Percutaneous Interventions

Lipomatous atrial septal hypertrophy (LASH) is a histologically benign cardiac lesion characterized by excessive fat deposition in the region of the interatrial septum that spares the fossa ovalis. The etiology of LASH remains unclear, though it may be associated with advanced age and obesity. Because of the sparing of the fossa ovalis, LASH has a pathognomonic dumbbell shape. LASH may be mistaken for various tumors of the interatrial septum. Histologically, LASH is composed of both mature and brown (fetal) adipose tissue, but the role of brown adipose tissue remains unclear. In interventional procedures requiring access to the left atrium, LASH may interfere with transseptal puncture, as traversing the thickened area can reduce the maneuverability of catheters and devices. This may cause the needle to enter the epicardial space, causing dangerous pericardial effusions. LASH was once considered a contraindication to percutaneous device closure of atrial septal defects because of an associated increased risk for incorrect device deployment. However, careful attention to preprocedural imaging and procedural intracardiac echocardiography enable interventional cardiologists to perform procedures in patients with LASH without serious complications. In this review article, the authors describe anatomic and functional aspects of LASH, with emphasis on their roles in percutaneous interventions.

Influence of PFO Anatomy on Successful Transcatheter Closure

Patent foramen ovale (PFO) is considered a risk factor for serious clinical syndromes, the most important of which is cryptogenic stroke in the setting of paradoxic embolism. The safety and feasibility of transcatheter PFO closure have been addressed in several studies; this procedure is performed worldwide with excellent results. Variations in the atrial septal configuration and PFO are frequent and have an impact on the technical aspects and success in transcatheter PFO closure. To minimize the rate of complications of percutaneous closure of PFO, patients must be carefully selected on the basis of morphology and location of the interatrial defect.

Patent foramen ovale closure and medical treatments for secondary stroke prevention: a systematic review of observational and randomized evidence

BACKGROUND AND PURPOSE

Patients discovered to have a patent foramen ovale in the setting of a cryptogenic stroke may be treated with percutaneous closure, antiplatelet therapy, or anticoagulants. A recent randomized trial (CLOSURE I) did not detect any benefit of closure over medical treatment alone; the optimal medical therapy is also unknown. We synthesized the available evidence on secondary stroke prevention in patients with patent foramen ovale and cryptogenic stroke.

METHODS

A MEDLINE search was performed for finding longitudinal studies investigating medical treatment or closure, meta-analysis of incidence rates (IR), and IR ratios of recurrent cerebrovascular events.

RESULTS

Fifty-two single-arm studies and 7 comparative nonrandomized studies and the CLOSURE I trial were reviewed. The summary IR of recurrent stroke was 0.36 events (95% confidence interval [CI], 0.24-0.56) per 100 person-years with closure versus 2.53 events (95% CI, 1.91-3.35) per 100 person-years with medical therapy. In comparative observational studies, closure was superior to medical therapy (IR ratio=0.19; 95% CI, 0.07-0.54). The IR for the closure arm of the CLOSURE I trial was higher than the summary estimate from observational studies; there was no significant benefit of closure over medical treatment (P=0.002 comparing efficacy estimates between observational studies and the trial). Observational and randomized data (9 studies) comparing medical therapies were consistent and suggested that anticoagulants are superior to antiplatelets for preventing stroke recurrence (IR ratio=0.42; 95% CI, 0.18-0.98).

CONCLUSIONS

Although further randomized trial data are needed to precisely determine the effects of closure on stroke recurrence, the results of CLOSURE I challenge the credibility of a substantial body of observational evidence strongly favoring mechanical closure over medical therapy.