Transnasal transoesophageal ultrasound: the end of the intracardiac echocardiography age?

The feasibility study of transnasopharyngeal esophagus echocardiography in the ultrasonic diagnosis

Background

Professor Xinfang Wang first introduced the clinical application of trans nose pharynx esophagus echocardiography (TNPEE) in 2014. Subsequently, we developed the technology. In the present study we assess the feasibility of TNPEE in the ultrasonic diagnosis.

Methods

Select patients suitable for TNPEE examination. After obtaining written consent of patients or their families, oral dacronin hydrochloride gel local anesthesia was given 10–15 min before examination. The nostrils were disinfected and then smeared with tetracaine hydrochloride gel, which acted as local anesthesia and lubrication. The probe was inserted gently through the nostrils and entered the esophagus through the nasal cavity and pharynx. TNPEE is similar to transoral esophagus echocardiography (TOEE) after the probe reaches the esophagus.

Results

TNPEE was performed in 103 patients. Forty-five patients (43.7%) underwent the examination successfully, 46 patients (44.7%) failed because of objective reasons, 12 patients midway refused to accept the examination and cancelled the examination, accounting for 11.6%, 11 patients (12.1%) suffered from epistaxis. Of all the patients with epistaxis, 9 had taken anticoagulant drugs, accounting for 82% of the patients with epistaxis. The vital signs of all patients were stable and no serious complications occurred.

Conclusion

Compared with TOEE, TNPEE can cause less nausea and vomiting reaction, and patients take longer time to undergo examination, which is conducive to more detailed examination. However, TNPEE has a high requirement for the probe, and its success rate is relatively low. It is easy to cause nasal bleeding in patients, so its wide clinical application is limited.

[Echocardiography during transcatheter interventions. New developments]

Interventional techniques for percutaneous treatment of structural heart disease have become an important option for patients ineligible for conventional operating procedures in cardiovascular medicine. Echocardiography plays an essential role not only for patient selection but also for guiding transcatheter interventions in order to safely accomplish the procedure. Echocardiographic 2D and 3D techniques next to conventional fluoroscopy have therefore become an integral part for monitoring interventional procedures in the catheter laboratory. This review aims to describe new developments for the application of echocardiography during transcatheter interventions in the context of the current literature and current recommendations.

A transoesophageal echocardiographic image acquisition protocol for wide-view fusion of three-dimensional datasets to support atrial fibrillation catheter ablation

PURPOSE

The aim of this paper is to propose a transoesophageal echocardiography (TOE) image acquisition protocol which provides a systematic manner of acquiring a minimal number of overlapping 3D TOE datasets allowing the reconstruction of a wide 3D view of the left atrium (LA) with anatomical landmarks that are important for atrial fibrillation catheter ablation.

METHODS

In eight cardiac surgical patients, 3D TOE datasets were acquired with a six-step protocol. In the protocol, step 1 aims to acquire the central view of the mitral valve (MV), aortic valve (AV) and left atrial appendage (LAA). Step 2 was developed to acquire the left pulmonary veins (PVs) and step 3 to acquire the right PVs. Steps 4, 5 and 6 were developed to create a sufficient overlap between different datasets. 3D TOE datasets were registered and fused manually in end diastole.

RESULTS

The image acquisition protocol was feasible in all patients. In the fused 3D dataset, a wide 3D view of the LA is shown, and left and right PVs could be seen simultaneously. The LAA, MV, AV and fossa ovalis (FO) were visualised clearly in the 3D TOE datasets. The PV ostia, which are located at the edges of the 3D datasets, suffered more from the artefact of echo loss. The volume overlaps between neighbouring TOE datasets were 50-75 %.

CONCLUSION

The major part of the LA anatomy incorporating the PVs, LAA, MV, AV and FO as important anatomical landmarks can be reconstructed by registering and fusing 3D datasets acquired with the six-step TOE image acquisition protocol.