Pocket-Sized Echo for Evaluation of Mitral and Tricuspid Regurgitation

Advances in electronic miniaturization and digital techniqueshave resulted in the advent of portable transthoracic echocar-diography (pTTE) imaging devices in the area of echocardiog-raphy. A pocket-sized pTTE imaging device that has colorDoppler imaging capability has been recently introduced intoclinical practice. This study aimed to examine the feasibilityand accuracy of the pocket-sized pTTE in the assessment ofthe severity of mitral regurgitation (MR) and tricuspid regur-gitation (TR).One hundred and eighty-six consecutive patients (ages 66 19 years; 107 male) underwent standard transthoracic echo-cardiography (sTTE) and pTTE. Initially, pTTE was per-formed by a well-trained sonographer for 121 patients. For thelater 65 patients, pTTE was examined by a less experiencedsonographer who had 6 months of experience in echocardiog-raphy, with the number of TTE examinations compatible withAmerican Society of Echocardiography training level 1 (1).These sonographers were blinded to sTTE results and allclinical information.This study was approved by the ethics committees of OsakaEkisaikai Hospital and Okayama University. Pocket-sized pTTEwas performed using the Vscan (GE Medical Systems, Milwau-kee,Wisconsin).Theapical4-chamberviewbythecolorDopplerimages was obtained with sTTE and pTTE, respectively. Theratio of regurgitant jet area to atrial area was then calculated forMR (%MR) and TR (%TR). The severity of regurgitation wasgraded as mild if it occupied 20%, moderate if between 20%and 34%, and severe if 34% in TTE examination.Linear regression analysis was used for the correlation ofvariables of interest. Differences were considered signicant atp 0.05.DifferencesbetweensTTEandpTTEresultswerealsocompared with the mean value obtained by sTTE and pTTEusing the Bland-Altman method, with the limits of agreementdened as 2 SD of the difference between the 2 methods.Echocardiographic measurements were completed for sTTEand pTTE in all patients (feasibility 100%). In the examinationby the well-trained sonographer, there were excellent correlationsin MR jet area, left atrial area, %MR, TR jet area, right atrialarea, and %TR between sTTE and pTTE (r 0.89 to 0.96, p 0.001). Also, there were small systematic differences with closelimits of agreement between sTTE and pTTE measurements,respectively: 20.2 cm