Park, Sung‐Ji

Background: Conventional transthoracic echocardiography (TTE) is currently not recommended as an initial test to diagnose coronary artery disease (CAD) due to its insensitivity. Left ventricular (LV) strain was reported to be more sensitive than regional wall motion abnormality (RWMA). The aim of this study was to evaluate the usefulness of TTE including LV strain analysis in initial assessment of acute chest pain in emergency department (ED). Methods: Patients visiting ED with acute chest pain were included. Patients with ST elevation myocardial infarct (MI), hemodynamic instability, known CAD or cardiomyopathy, high probability of non-cardiac chest pain, and poor echocardiographic window were excluded. All the patients were initially assessed by an ED physician for pretest probability of CAD. TTE was performed including LV strain image and global and regional LV longitudinal stain (S GL and S RL ) was analyzed online. S RL abnormality was defined as decreased S RL in at least 2 adjacent segments. Diagnosis of CAD (based on coronary angiography or CT angiography) and cardiac events (cardiac death, revascularization, MI, or recurrent ED visit due to chest pain) were reviewed at 1 month after ED visit. Results: Overall 104 patients were analyzed. CAD was diagnosed in 24% (n=25) and cardiac event was detected in 25% (n=26) of patients.Diagnostic accuracy for CAD was higher when using S RL with cut-off value of -13% (sensitivity of 89%, specificity of 77%, NPV = 92%, PPV = 70%) than when using RWMA (sensitivity of 62%, specificity of 88%, NPV = 80%, PPV = 76%). S RL showed better diagnostic performance for CAD than S GL , and pretest probability (Figure). Predictive value of S RL for cardiac events was also highest in those of S GL , RWMA, and pretest probability (Figure). Conclusion: LV strain echocardiography can diagnose the CAD and predict future events with high accuracy. TTE including strain analysis can be used as an initial diagnostic tool in evaluation of acute chest pain in ED.

Backgrounds: Left ventricular torsion (LVtor) is an integral part of systole and untwisting plays an important role in diastole. The aim of this study was to characterize LVtor and untwisting in different grades of diastolic dysfunction. Methods: We studied 135 patients with normal LV EF with various grades of diastolic dysfunction (40 group1:mild,42 group 2:moderate,and 22 group 3:severe dysfunction) and 31 controls with normal diastolic function. Apical and basal short axis rotations were measured by 2D STE. LVtor was defined as net difference between apical and basal rotation. Results: Age, gender, and EF were similar in 3 groups and control. Mitral annulus early diastolic velocity was reduced in all 3 groups (see table ). Peak LVtor was significantly greater in group 1 compared with control, group 2 and group 3. The time from peak LVtor to Mitral valve opening, and to peak early diastolic velocity were significantly delayed in group 1 compared to control (p=0.0030 and 0.0409, respectively). The twisting rate and untwisting rate were found to be highest in group 1. Conclusions: Systolic torsion and diastolic untwisting are significantly increased in patients with mild diastolic dysfunction. In patients with advanced diastolic dysfunction with increased filling pressure, torsion and untwisting are normalized. Hence, vigorous LV torsion appears to be a compensatory mechanism during an early stage of diastolic dysfunction to maintain normal filling in the setting of reduced longitudinal myocardial motion.