Transcranial Doppler: Does Addition of Blood to Agitated Saline Affect Sensitivity for Detecting Cardiac Right-to-Left Shunt?

Background: Transcranial Doppler (TCD) with agitated saline has been shown to be an alternative for the detection of right-to-left shunts (RLS) with similar diagnostic accuracies as transesophageal echocardiography (TEE). It is hypothesized that the addition of blood to agitated saline increases the sensitivity of TCD for the detection of RLS. The aim of this meta-analysis was to determine whether agitated saline with blood increases the sensitivity of TCD for the detection of RLS compared to agitated saline alone and other contrast agents.

Usefulness of Transcranial Doppler for Detecting Pulmonary Arteriovenous Malformations in Hereditary Hemorrhagic Telangiectasia.

The aim of this study was to assess transcranial Doppler (TCD) as a screening test for pulmonary arteriovenous malformation (PAVM) in patients with hereditary hemorrhagic telangiectasia (HHT). This retrospective study included suspected patients with HHT who were screened for PAVM with a TCD and a chest computed tomography (CT) study. The results of TCD and CT were compared to evaluate the usefulness of TCD for detecting PAVM.

Patent foramen ovale: Unanswered questions.

The foramen ovale is a remnant of the fetal circulation that remains patent in 20-25% of the adult population. Although long overlooked as a potential pathway that could produce pathologic conditions, the presence of a patent foramen ovale (PFO) has been associated with a higher than expected frequency in a variety of clinical syndromes including cryptogenic stroke, migraines, sleep apnea, platypnea-orthodeoxia, deep sea diving associated decompression illness, and high altitude pulmonary edema. A unifying hypothesis is that a chemical or particulate matter from the venous circulation crosses the PFO conduit between the right and left atria to produce a variety of clinical syndromes.

Sleep Apnea in Patients with and without a Right-to-Left Shunt.

Objectives: To assess the presence of right-to-left shunting (RLS) in patients with obstructive sleep apnea (OSA), and compare clinical characteristics and parameters of the sleep studies of patients with and without RLS.

Background: The most common cause of RLS is due to intermittent flow through a patent foramen ovale (PFO). PFO occurs more frequently in patients with OSA and may be involved in the exacerbation of OSA.

The effect of patent foramen ovale closure in patients with platypnea-orthodeoxia syndrome.

Background: Platypnea-orthodeoxia syndrome is a rare condition characterized by hypoxemia in the upright position that is improved in the supine position. Although several etiologies of platypnea-orthodeoxia exist, it is frequently associated with right-to-left shunting of blood at the cardiac or pulmonary level, usually via a patent foramen ovale (PFO). The aim of this study was to evaluate the incidence of platypnea-orthodeoxia syndrome in a select patient population with right-to-left shunting and to describe the outcomes after PFO closure.

Two-dimensional echocardiography using second harmonic imaging for the diagnosis of intracardiac right-to-left shunt: a meta-analysis of prospective studies.

Right-to-left shunting (RLS), usually through a patent foramen ovale (PFO), has been associated with migraine, cryptogenic stroke and hypoxemia. With emerging observational studies and clinical trials on the subject of PFO, there is a need for accurate diagnosis of PFO in patients being considered for transcatheter closure. While transesophageal echo (TEE) bubble study is the current standard reference for diagnosing PFO, transthoracic echo with second harmonic imaging (TTE-HI) may be a preferable screening test for RLS due to its high accuracy and non-invasiveness.

Accuracy of conventional transthoracic echocardiography for the diagnosis of intracardiac right-to-left shunt: a meta-analysis of prospective studies.

Background: Paradoxical embolization through a right-to-left shunt (RLS), often from a patent foramen ovale (PFO), has been associated with cryptogenic stroke. While transesophageal echo (TEE) bubble study is the current standard reference for diagnosing PFO, transthoracic echo (TTE) remains the most commonly used screening test for RLS due to its noninvasiveness and easy availability. The aim of this meta-analysis was to determine the accuracy of TTE compared to TEE as the reference.

Association of ischemic stroke, hormone therapy, and right to left shunt in postmenopausal women.

Background: Postmenopausal hormone therapy (HT) increases the risk of venous thrombosis and ischemic stroke.

Objectives: We postulated that HT might increase the risk of ischemic stroke by promoting venous clots that travel to the brain through a right to left shunt (RLS).

Methods: A total of 2,389 records were studied.

Accuracy of transcranial Doppler for the diagnosis of intracardiac right-to-left shunt: a bivariate meta-analysis of prospective studies.

Objectives: The aim of this meta-analysis was to determine the accuracy of transcranial Doppler (TCD) compared with transesophageal echocardiography (TEE) as the reference.

Background: Right-to-left shunting (RLS), usually through a patent foramen ovale (PFO), has been associated with migraine, cryptogenic stroke, and hypoxemia. With emerging observational studies and clinical trials on the subject of PFO, there is a need for accurate diagnosis of PFO in patients with these conditions, and those being considered for transcatheter closure.

Comparison of residual shunt rates in five devices used to treat patent foramen ovale.

Objectives: To assess the effective closure rate among devices used for transcatheter patent foramen ovale (PFO) closure, and to discuss the management of patients with large residual shunts.

Background: Several devices are used off-label for transcatheter closure of a PFO in the United States. The rate of residual shunting after PFO closure varies by device.

Sensitivity of brachial versus femoral vein injection of agitated saline to detect right-to-left shunts with Transcranial Doppler.

Background: Transcranial Doppler (TCD) can detect a right-to-left shunt (RLS) with high sensitivity but has a 5% chance of a false negative study. TCD is usually performed with injection of agitated saline into an arm vein. We compared the sensitivity of TCD performed from the brachial versus femoral veins.

Accuracy of stress myocardial perfusion imaging to diagnose coronary artery disease in end stage liver disease patients.

Patients with end-stage liver disease (ESLD) who also have underlying coronary artery disease (CAD) may be at increased risk for undergoing hemodynamically challenging orthotopic liver transplantation. Noninvasive single-photon emission computed tomographic (SPECT) imaging is often used to determine whether a patient with ESLD has unsuspected CAD. The objective of this study was to determine the accuracy of SPECT imaging for detection of CAD in patients with ESLD.

Incidence of patent foramen ovale and migraine headache in adults with congenital heart disease with no known cardiac shunts.

The purpose of this study was to understand why patients with adult congenital heart disease (CHD) but no obvious shunt have an increased frequency of migraine headaches (MH). CHD patients with no known cardiac shunts (CHD-NKS), based on their echocardiographic or angiographic procedures, were tested for a right-to-left shunt using agitated saline contrast transcranial Doppler (TCD). Medical records of 2,920 patients from the UCLA Adult CHD Center were screened to participate in a study to evaluate the prevalence of MH in adults with CHD; 182 patients (6.

Visual migraine aura with or without headache: association with right to left shunt and assessment following transcutaneous closure.

Background: Right to left shunting, usually caused by a patent foramen ovale (PFO), is associated with migraine and visual aura. It is unknown if patients who present with visual aura without headache behave similarly to those experiencing typical migraine headache with aura. The purpose of this study was to assess the prevalence of right to left shunting in patients who present with migraine aura without headache and evaluate the response to PFO closure.

The effect of patent foramen ovale closure on visual aura without headache or typical aura with migraine headache.

Objectives: The aim of this study was to assess the prevalence of right-to-left (R to L) shunt in patients with visual aura and evaluate the effect of shunt closure on resolution of aura.

Background: Right-to-left shunting is associated with migraine headache (MH) with aura. Some patients present with visual aura without headaches.

The association of patent foramen ovale morphology and stroke size in patients with paradoxical embolism.

Background: Patent foramen ovale (PFO) has been implicated in the pathogenesis of cryptogenic stroke through paradoxical embolization to the cerebral circulation. This study evaluated the relationship between the morphological and functional size of the PFO by echocardiography compared with cerebral infarct volume identified on MRI.

Methods And Results: Patients who were referred to interventional cardiology with the diagnosis of cryptogenic stroke were included and had either a transesophageal echocardiogram or an intracardiac echo and a brain MRI at the time of stroke.

Sensitivity of transcranial Doppler versus intracardiac echocardiography in the detection of right-to-left shunt.

Objectives: The purpose of this study was to understand the reason for variation in the sensitivity of different methods of detecting right-to-left shunts (RLS).

Background: Patent foramen ovale (PFO) is implicated in the pathogenesis of cryptogenic stroke, decompression illness, and migraine headaches. Intravenous agitated saline injections with tomographic imaging (transthoracic, transesophageal, and intracardiac echocardiography) has been used for detecting intracardiac shunts.