title: Instantaneous Decrease in Left Ventricular Afterload during Transcatheter Aortic Valve Implantation Results in Immediate Changes in Left Ventricular Strain.
abstract: Severe aortic stenosis causes chronic increased afterload on the left ventricle (LV) resulting in myocardial hypertrophy and ultimately dysfunction if left untreated. Transcatheter aortic valve implantation (TAVI) immediately decreases the afterload on the LV by reducing the pressure gradient through the aortic valve. In our study, we aim to evaluate immediate changes in LV mechanics using intra-procedural transesophageal echocardiography (TEE) to assess circumferential and radial strain via speckle tracking. Intra-operative TEE was performed during TAVI for 53 patients (mean age 84 ± 8 years). Two-dimensional images in the transgastric view were acquired at the level of the papillary muscle. Circumferential and radial strain was calculated using speckle tracking with Philips Qlab software. Global LV afterload was measured by calculating valvulo-arterial impedance (Zva). Immediately post-TAVI, there was a change in both radial strain rate (Pre: 0.73 ± 0.04 vs. Post: 0.88 ± 0.04 per second, P < 0.001) and circumferential strain rate (-0.53 ± 0.04 (pre) vs. -0.74 ± 0.04 (post) per second, P < 0.001). There was also an immediate improvement in circumferential global strain parameters (-14.5 ± 5% (pre) vs. -16.0 ± 4.7% (post), P < 0.05), whereas there was no significant change seen in global radial strain (15.6 ± 0.8% (pre) vs. 15.2 ± 0.9% (post), P = 0.69). No significant change was seen in LV ejection fraction (51.5 ± 14.2% (pre) vs. 52.1 ± 14.0% (post), P = 0.77). Speckle tracking using TEE images is feasible and identifies significant improvements in LV strain and strain rate immediately following TAVI that is not detected by conventional measure of LV function.
authors.affiliation: Department of Cardiovascular Medicine, Flinders Medical Centre, Adelaide, SA, Australia.
authors.forename: Amy
authors.initials: A
authors.lastname: Swan
authors.affiliation: Department of Cardiovascular Medicine, Flinders Medical Centre, Adelaide, SA, Australia.
authors.forename: Roshan
authors.initials: R
authors.lastname: Prakash
authors.affiliation: Department of Cardiovascular Medicine, Flinders Medical Centre, Adelaide, SA, Australia.|Flinders University, Adelaide, SA, Australia.
authors.forename: Derek P
authors.initials: DP
authors.lastname: Chew
authors.affiliation: Department of Cardiovascular Medicine, Flinders Medical Centre, Adelaide, SA, Australia.|Flinders University, Adelaide, SA, Australia.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Perry
authors.affiliation: Department of Cardiovascular Medicine, Flinders Medical Centre, Adelaide, SA, Australia.|Flinders University, Adelaide, SA, Australia.
authors.forename: Ajay
authors.initials: A
authors.lastname: Sinhal
authors.affiliation: Department of Cardiovascular Medicine, Flinders Medical Centre, Adelaide, SA, Australia.|Flinders University, Adelaide, SA, Australia.|Flinders Clinical Research (FCR), South Australian Health and Medical Research Institute, Adelaide, SA, Australia.
authors.forename: Joseph B
authors.initials: JB
authors.lastname: Selvanayagam
authors.affiliation: Department of Cardiovascular Medicine, Flinders Medical Centre, Adelaide, SA, Australia.|Flinders University, Adelaide, SA, Australia.
authors.forename: Majo X
authors.initials: MX
authors.lastname: Joseph
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001024:Aortic Valve Stenosis / Q000150:complications / Q000503:physiopathology* / Q000601:surgery*; D004452:Echocardiography / Q000379:methods*; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013314:Stress, Mechanical; D013318:Stroke Volume; D065467:Transcatheter Aortic Valve Replacement; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000209:etiology / Q000503:physiopathology* / Q000517:prevention & control*; D017725:Ventricular Pressure
keywords: aortic stenosis; strain; transesophageal echocardiography