Detection of left-to-right shunt in atrial septal defect by negative contrast echocardiography: a comparison of transthoracic and transesophageal approach

Intracardiac Echocardiogram: Feasibility, Efficacy, and Safety for Guidance of Transcatheter Multiple Atrial Septal Defects Closure

We aimed to determine the feasibility, efficacy, success, and safety of intracardiac echocardiography (ICE) in transcatheter multiple atrial septal defect (ASD) closure. Of 185 patients with multiple ASDs who underwent transcatheter closure, 140 (76%) patients who weighed <30kg with a narrow distance between defects or in whom single device closure was anticipated were guided by ICE and 45 patients were guided by three-dimensional (3D) transesophageal echocardiography (TEE) with or without ICE. Patients in the ICE group were relatively younger and weighed less than those in the 3D TEE group (p < 0.0001). The ratio of the distance between defects >7 mm was high, and more cases required ≥2 devices in the 3D TEE group than those in the ICE group (p < 0.0001). All patients in the 3D TEE group and seven patients (5%) in the ICE group were operated on under general anesthesia (p < 0.0001). The fluoroscopic time was shorter in the ICE group (13.98 ± 6.24 min vs. 24.86 ± 16.47 min, p = 0.0005). No difference in the complete closure rate and complications was observed. ICE-guided transcatheter and 3D TEE were feasible, safe, and effective in successful multiple ASD device closures, especially for young children and patients at high risk under general anesthesia.

Point-of-care echocardiography for the evaluation of right-to-left cardiopulmonary shunts: a narrative review

Right-to-left pulmonary and cardiac shunts (RLS) are important causes of refractory hypoxia in the critically-ill perioperative patient. Using a point-of-care ultrasound (POCUS) agitated saline bubble study for an early diagnosis allows patients with clinically significant RLSs to receive expedited therapy. This narrative review discusses the principles of agitated saline ultrasonography as well as the role of POCUS in detecting the most common RLS types seen in the intensive care unit, including patent foramen ovale, atrial septal defects, and pulmonary arterio-venous malformations. An illustrated discussion of the procedure, as well as shunt-enhancing maneuvers (Valsalva or lung recruitment maneuver with subsequent rapid release) is provided. With the wide dissemination of bedside ultrasound within the perioperative and critical care arena, POCUS practitioners should be knowledgeable of the potential pitfalls leading to both false-positive and false-negative studies. False-positive studies may be due to congenital abnormalities, mischaracterization of intrapulmonary shunts as intracardiac shunts (and vice versa), or evidence of the Valsalva effect. False negatives are typically due to respiratory-phasic variation, performing an inadequate shunt-enhancing maneuver, inadequate injection of agitated saline, or pathophysiologic states of elevated left atrial pressure. Finally, alternative POCUS methods for determining presence of an RLS in patients with poor echocardiographic windows are discussed, with a focus on pulsed-wave Doppler interrogation of arterial signals.

Patent foramen ovale in idiopathic pulmonary arterial hypertension: Long-term risk and morbidity

INTRODUCTION

Little is known about the presence of patent foramen ovale in idiopathic pulmonary arterial hypertension. While there is suspected worsening of hypoxemia confounding assessment and management of pulmonary hypertension, as well as possible increased morbidity from paradoxical emboli, there may be theoretical relief of worsening right-sided pressures by the same mechanism of right-to-left shunting.

METHODS

Retrospective review of consecutive patients diagnosed with idiopathic pulmonary arterial hypertension (WHO Group 1) via right heart catheterization, from 1998 to 2010. All patients also underwent a four chamber transthoracic echocardiogram with agitated saline contrast for the evaluation of patent foramen ovale. Primary clinical data was collected and compared between patients with and without patent foramen ovale along with univariable and multivariable predictors of long term survival.

RESULTS

One hundred and fifty five patients were included in the study, 42 with patent foramen ovale (27%). Patients with patent foramen ovale were younger at pulmonary arterial hypertension diagnosis and trended towards higher right ventricular systolic pressures on echocardiography and mean pulmonary arterial pressures by right heart catheterization. Predictors of mortality included age, diffusing capacity for carbon monoxide, and severe hypoxemia. Only diffusing capacity and age were predictive of mortality after adjustment for a priori covariables.

CONCLUSION

Patent foramen ovale is seen in a quarter of patients with idiopathic pulmonary arterial hypertension and associated with increased prevalence of severe hypoxemia but had no effect on long term survival.

Usefulness of the right parasternal approach to evaluate the morphology of atrial septal defect for transcatheter closure using two-dimensional and three-dimensional transthoracic echocardiography

BACKGROUND

The aim of this study was to demonstrate the feasibility and usefulness of addition of the right parasternal approach to the conventional left parasternal and apical approaches using two-dimensional (2D) and three-dimensional (3D) transthoracic echocardiography (TTE) for morphologic evaluation in cases of transcatheter closure of atrial septal defects (ASDs).

METHODS

In 112 consecutive patients with ASDs, the morphology of the defects was evaluated for transcatheter closure in the right parasternal view in addition to the conventional left views using 2D and 3D TTE. Measurements of the maximal ASD diameter and detection of deficient rim obtained on 2D TTE were compared with those obtained by 2D transesophageal echocardiography. The shapes and locations of ASDs visualized by 3D TTE were compared with those visualized by 3D transesophageal echocardiography.

RESULTS

In 88 patients (80.0%), optimal images from the right parasternal approach for morphologic evaluation of ASDs were obtained. Although there was a significant difference in maximal ASD diameter obtained only in the conventional left approach compared with transesophageal echocardiographic measurements (P < .05), when the right parasternal approach was applied, a significant difference was not found (P = .18), and the diagnostic concordance of the rim deficiency was improved from 85.2% to 90.9%. Three-dimensional TTE from the right parasternal approach improved visualization of the shape and location of ASDs from 65.5% to 74.5%.

CONCLUSIONS

Additional use of the right parasternal approach enables detailed morphologic evaluation for transcatheter closure of ASDs. In patients with suboptimal images on 3D TTE in the left conventional approach, additional 3D TTE in the right parasternal approach can improve the feasibility of obtaining optimal 3D images to evaluate the shapes and locations of ASDs.

Pulmonary hypertension: clinical manifestations, classification and diagnosis

Dyspnoea on exertion is the most common presenting symptom of pulmonary hypertension (PH), often a progressive and ultimately fatal condition. However, the presenting manifestations are protean, and more subtle features such hoarseness (caused by compression of the left recurrent laryngeal nerve) challenge master clinicians. Clinician scientists have refined the clinical classification in a manner that aids in accurate diagnosis and facilitates communication among healthcare providers and research investigators. Diagnostic algorithms emphasize confirmation and characterization of PH by catheterisation as well as differentiating between the current classes based upon essential and contingent diagnostic tests.

Left atrial appendage assessment by second harmonic transthoracic echocardiography after an acute ischemic neurologic event

Although second harmonic (sh) imaging is widely available in most contemporary ultrasound systems, its accuracy to evaluate left atrial appendage (LAA) morphology and function remains poorly characterized. We conducted a cross-sectional survey of patients with acute ischemic neurologic conditions (n = 51) who underwent both transesophageal and transthoracic echocardiography (TTE) to explore the performance of sh in LAA assessment. Doppler and LAA area evaluation by sh TTE were feasible in most patients (98%). We observed positive and significant associations between sh TTE and transesophageal echocardiography assessment of LAA peak emptying velocities (r = 0.63, P < .001) and LAA maximum area (r = 0.73, P < .001). In addition, all patients (n = 7) with LAA thrombus or spontaneous contrast had peak emptying velocities less than 50 cm/s on sh TTE (negative predictive value of 100%). In multivariate analysis, LAA peak emptying velocity remained independently associated with LAA thrombus or contrast. In conclusion, sh TTE can provide valuable and clinically relevant information of LAA morphology and dynamics.

[Echocardiographic evaluation in unoperated congenital heart disease in adults]

Echo and Doppler echocardiographic procedures have gained special importance in the diagnostics of congenital diseases in adults. These procedures permit detailed visualization of the pathomorphology of the heart as well as reliable evaluation of the hemodynamic changes. There are differentiated indications for the various procedures, such as transthoracic and transesophageal echocardiography, Doppler and color-Doppler echocardiography, contrast echocardiography and 3-dimensional echocardiography. This article discusses the opposition of the various echo and Doppler echocardiographic procedures with respect to the diagnostics of the most frequent non-operated congenital diseases in adults. The pathomorphology of the various congenital diseases will be summarized and then the important echocardiographic criteria presented which are decisive for the diagnostic procedure. In simple congenital malformation of cardiac valves, such as bicuspid aortic valve (Figure 1: aortic ring abscess), pulmonary valve stenosis (Figure 2), Ebstein's anomaly (Figure 3) or malformations of the mitral valve (Figure 4: cleft in the anterior mitral cusp), the diagnosis can often be made using transthoracic echo and Doppler echocardiography, and the severity of the defect determined. However, the sonographic conditions, especially in adults, are frequently too limited to permit recognition of detailed smaller changes, so that transesophageal examination is required to finally confirm the diagnosis in these patients. In the diagnostics of diseases of the left ventricular outflow tract and the thoracic aorta, such as subvalvular aortic valve stenosis (Figure 5), the sinus of Valsalva aneurysm or the coarctation of the aorta (Figure 6), the left ventricular outflow tract can be evaluated morphologically from a transthoracic procedure and the accelerations of flow can be recorded by continuous wave Doppler. If there is no sclerosis of the fibrous membrane, these can often not be depicted by transthoracic procedures, so that a supplementary transesophageal examination is meaningful. This is required in any case for diseases of the descending thoracic aorta. In the case of congenital lesions, such as atrial septal defects (Figure 7: anomalous pulmonary venous return, Figure 8: 3-dimensional visualization of an atrial septal defect, Figure 9: sinus venosus defect), ventricular septal defect or a patent ductus arteriosus Botalli (Figure 10), color-Doppler and contrast echocardiography have become especially important. Transesophageal examination is also indicated for these congenital diseases for direct depiction of the defect as well as for precise evaluation of the shunt. Moreover, in atrial septal defects, it has been shown that a 3-dimensional echocardiography provides additional advantage with respect to spatial relationship of the defect to the other cardiac structures, as well as presenting dynamic changes during a heart cycle. Extensive knowledge of complex congenital heart disease, such as tetralogy of Fallot (Figure 11), complete transposition of the great arteries, congenitally corrected transposition of the great arteries (Figure 12), the double-outlet right ventricle, truncus arteriosus communis, the cor triatriatum, tricuspid atresia (Figure 13) or the univentricular heart (Figure 14) usually requires performance of a transthoracic echo- and Doppler echocardiographic examination to assess the pathomorphological changes and to examine hemodynamics. In the majority of patients, supplementary transesophageal echocardiography and an echo contrast examination are important. Initial examinations using 3-dimensional echocardiography are very promising in this connection and with respect to the exact spatial presentation of pathoanatomical structures.

Transesophageal echocardiography

This article presents an overview of the benefits and efficacy of transesophageal echocardiography (TEE) in the critically ill patient. The echocardiographic evaluation of ventricular function both regional and global, is discussed with special emphasis on ischemic heart disease; assessment of preload, interrogation of valvular heart disease (prosthetic and native) and its complications; endocarditis and its complications; intracardiac and extracardiac masses, including pulmonary embolism; aortic diseases (e.g., aneurysan, dissection, and traumatic tears); evaluation of patent foramen ovale and its association with central and peripheral embolic events; advancements in computer technology; and finally, the effect of TEE on critical care.

Scintigraphic demonstration of a right-to-left intracardiac shunt in a patient with massive pulmonary emboli

A case of massive pulmonary embolism resulting in marked pulmonary to systemic shunting in a patient with a previously clinically inapparent ventricular or atrial septal defect is presented. The various types of unrecognized intracardiac shunts and their prevalence in the adult population are discussed.

Intracardiac shunts

Unsuspected intracardiac shunts can be a cause of acute deterioration in critically ill patients. Shunts can be acquired or congenital conditions that become symptomatic only with changed physiologic conditions. Transesophageal echocardiography is an excellent tool for the diagnosis of intracardiac shunts.