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Sitara G Khan, Dimitris Klettas, Stam Kapetanakis and Mark J Monaghan


Cardiac resynchronisation therapy (CRT) can profoundly improve outcome in selected patients with heart failure; however, response is difficult to predict and can be absent in up to one in three patients. There has been a substantial amount of interest in the echocardiographic assessment of left ventricular dyssynchrony, with the ultimate aim of reliably identifying patients who will respond to CRT. The measurement of myocardial deformation (strain) has conventionally been assessed using tissue Doppler imaging (TDI), which is limited by its angle dependence and ability to measure in a single plane. Two-dimensional speckle-tracking echocardiography is a technique that provides measurements of strain in three planes, by tracking patterns of ultrasound interference (‘speckles’) in the myocardial wall throughout the cardiac cycle. Since its initial use over 15 years ago, it has emerged as a tool that provides more robust, reproducible and sensitive markers of dyssynchrony than TDI. This article reviews the use of two-dimensional and three-dimensional speckle-tracking echocardiography in the assessment of dyssynchrony, including the identification of echocardiographic parameters that may hold predictive potential for the response to CRT. It also reviews the application of these techniques in guiding optimal LV lead placement pre-implant, with promising results in clinical improvement post-CRT.

Open access

Dimitris Klettas, Emma Alcock, Rafal Dworakowski, Philip MacCarthy and Mark Monaghan


The role of transoesophageal echocardiography in cardiac interventional structural procedures is well established and appreciated. However, the need for general anaesthesia (GA) throughout the procedure remains a controversial issue. The aim of the present study is to assess the feasibility and imaging quality of using a transnasal microrobe that allows the usage of conscious sedation in patients who undergo cardiac structural interventional procedures without missing the benefits, guidance and navigation of conventional trans-procedural TEE.


We analysed the trans-procedural images of 24 consecutive patients who underwent TAVI, TMVI or ASD/PFO closure, using a transnasal 2D microprobe (PHILIPS) and then we compared them with images taken by using a conventional 3D TEE probe (PHILIPS). In particular, we compared the imaging quality of the two probes regarding: (1) The anatomy, visualisation of valvular calcification and transvalvular colour Doppler of the aortic and mitral valve; (2) the imaging quality of PFO, ASD and interatrial communication colour flow; (3) the imaging of left ventricle systolic function and pericardial space and (4) transgastric imaging.


All images were graded with a scale from 5 to 1. The average grade of imaging quality in the mitral valve was: anatomy, 4.3; calcification, 3.8; colour Doppler, 4.2. The average grade of imaging quality in the aortic valve was: anatomy, 4.3; calcification, 3.7; colour Doppler, 4.3. The average grade of imaging quality in PFO/ASD was 4.3. The average grade of imaging quality in LV/pericardial space was 4.2. The average grade of imaging quality in transgastric imaging was 4.1.


These results suggest that transnasal TEE can provide good anatomical image quality of relevant cardiac structures during cardiac structural interventions and this may facilitate these procedures being performed during conscious sedation without having to lose TEE guidance.