Preoperative Pocket Echocardiography Trial

Overview

This study will compare findings using a handheld ultrasound device (GE VScan) with those using a diagnostic ultrasound machine in adult patients referred for transthoracic echo (TTE), prior to non-cardiac surgery at Hammersmith Hospital, London. The handheld TTE (VTTE) will follow the standard Hammersmith Hospital diagnostic TTE (DTTE) protocol (with the exception of spectral Doppler) and will be reported on a simple 'tick box' form. A different echocardiographer will then perform and report the DTTE as per routine practice. The results from VTTE and DTTE will be directly compared. The echocardiographers performing the VTTE and DTTE are all fully accredited in diagnostic TTE and will be blinded to each others findings. The study aims to recruit a total of 96 patients with an anticipated study completion date of November 2015.

Handheld echocardiography has become a practical reality with the development of small and highly portable devices. The GE VScan is one such device and a number of studies have examined its diagnostic capabilities in different clinical settings however, no study has examined its capability for screening non-cardiac surgical patients in the preoperative setting. If VTTE could be shown to safely screen patients preoperatively then there is potential to save time and money. DTTE is more costly than VTTE and there are often delays in performing DTTE prior to surgery. Adult patients \> 17 years old who are referred for a preoperative TTE prior to non-cardiac surgery (elective or emergency procedures) are eligible for recruitment. Once an eligible patient is identified verbal and written consent to participate will be obtained. VTTE will be performed by one of six accredited echocardiographers working in Hammersmith Hospital Echocardiography Department. Based on pilot data and previously published studies it is estimated the VTTE will take between 3 and 7 minutes. The VTTE is reported on a 'tick box' form with the findings separated into significant pathology (red zone) and insignificant pathology or normal findings (black zone). DTTE will then be performed by a different echocardiographer and a written report prepared as per normal practice. The written DTTE report will be converted to a 'tick box' report enabling direct comparison of VTTE and DTTE. The primary aim is to assess the ability of the VTTE to detect significant pathology identified on DTTE. A proportion of DTTE and VTTE will be re-rated to obtain a measure of inter- and intra- observer variability.