JOURNAL OF EVIDENCE BASED MEDICINE AND HEALTHCARE

Table of Contents

2019 Month : December Volume : 6 Issue : 52 Page : 3259-3264

Utility of Longitudinal Strain Imaging by Speckle Tracking in Predicting Obstructive Coronary Artery Disease in Patients without Regional Wall Motion Abnormality on 2D Echocardiography

Kiran Gopinath1, Sajan Zulfikar Ahmad2, Sunitha Viswanathan3, George Alummoottil Koshy4

Corresponding Author:
Dr. Sajan Ahmad Z,
#16 FG, Skyline Edge,
Thirumoolapuram,
Thiruvalla- 689115,
Kerala, India.
E-mail: sajanahmad@gmail.com
DOI: 10.18410/jebmh/2019/683

ABSTRACT
BACKGROUND
Strain imaging by speckle tracking is a well-established method to assess left ventricular function. The objective of this study was to define the utility of strain imaging in predicting obstructive coronary artery disease (CAD) in a subset of patients who do not have regional wall motion abnormality (RWMA) on routine 2D echocardiography.

METHODS
This is a prospective study. Consecutive patients with no RWMA scheduled to undergo coronary angiography (CAG) for clinical indications were included in the study. Longitudinal strain imaging by speckle tracking using automated functional imaging (AFI) was done by a single investigator prior to CAG. All angiograms were reported by a second investigator who was blinded to the strain imaging findings. Obstructive CAD was defined as ≥ 70% luminal stenosis of epicardial coronary arteries and/or ≥ 50% luminal stenosis of LMCA.

RESULTS
129 patients were enrolled over a 7 month period (mean age 56.07±10.7, males 69%, females 31%). For detecting obstructive CAD, strain imaging had a sensitivity of 97% for LAD, 90.69% for RCA, 91.6% for LCX, a negative predictive value of 81.81% for LAD, 91.3% for RCA, 92.3% for LCX, a specificity of 15.2% for LAD, 13.9% for RCA, 22.8% for LCX and a positive predictive value of 57.6% for LAD, 34.5% for RCA and 21.3% for LCX territories. Patients with obstructive CAD had a lower global strain value of -18.37 ± 4.13 as compared to -21.18 ± 3.81 in patients who did not have obstructive CAD (p value <0.01).

CONCLUSIONS
Peak longitudinal strain imaging by speckle tracking is a very sensitive (ranging from 90.69% to 97.14%) test with a high negative predictive value (ranging from 75% to 92.3%) for identifying obstructive coronary artery lesions on coronary angiography. These properties make strain imaging a good screening test to rule out significant CAD, especially when the pre-test probability is low.

KEYWORDS
Strain Echocardiography, Speckle Tracking, Coronary Angiography