Atsuko Furukawa

Comparison of two-dimensional and real-time three-dimensional transesophageal echocardiography in the assessment of aortic valve area

BACKGROUND The accuracy of two-dimensional transesophageal echocardiography (2D-TEE) for the measurement of aortic valve area (AVA) in patients with aortic stenosis (AS) depends upon the cross-section selected for imaging. Real-time three-dimensional transesophageal echocardiography (3D-TEE) may overcome this limitation of 2D-TEE. The goal of this study was to compare 3D-TEE with 2D-TEE for the measurement of AVA. METHODS AND RESULTS Twenty-five patients with AS underwent TEE. In 2D-TEE, the aortic valve image was obtained at the orifice level in the short-axis view, and AVA was measured by planimetry of the acquired images (2D-AVA). In 3D-TEE, 3D data containing the entire aortic valve were obtained. Then, a short-axis cross-section containing the smallest orifice in mid-systole was cut from the 3D data during image postprocessing, and the AVA was measured by planimetry (3D-AVA). The 3D-AVA was significantly smaller than the 2D-AVA (0.79±0.35cm(2) vs. 0.93±0.40cm(2), p<0.0001), but there was a strong correlation between 3D-AVA and 2D-AVA (R=0.94). Although the frame rate was lower in 3D-TEE than in 2D-TEE (17±6Hz vs. 58±16Hz), the 3D-AVA determined at each frame during systole showed that the difference between 3D-AVA and 2D-AVA was not explained by the lower frame rate. The time required for image acquisition of the aortic valve was shorter with 3D-TEE than with 2D-TEE (p=0.0005). CONCLUSIONS The geometric AVA is smaller with 3D-TEE than with 2D-TEE, and the difference is not due to the lower frame rate of 3D-TEE. The improved accuracy of 3D-TEE along with reduced image acquisition time indicates that 3D-TEE is superior to 2D-TEE for the assessment of AVA.

Stenting of right coronary ostial occlusion due to thrombosed type A aortic dissection: One-year follow-up results

A 52-year-old man experienced acute chest pain and was transferred to our hospital. An electrocardiogram showed ST-segment elevation in leads II, III, aVf, and V1 through V3. The diagnosis at the emergency room was inferior acute myocardial infarction (AMI), and emergent coronary angiography (CAG) was performed. While CAG showed subtotal occlusion of the right coronary artery (RCA) ostium, aortic dissection was suspected due to staining of the contrast agent distal to the occluded site of RCA. Intravascular ultrasound showed compression of the RCA ostium due to aortic dissection. We performed bare metal stent implantation, and contrast-enhanced computed tomography (CT) after stenting showed a thrombosed type A aortic dissection. The patient received medical treatment along with repeated CT and echocardiographic examinations, and was discharged without any events one month after admission. CAG six months after stenting and 64-multislice CT angiography one year later showed a patent RCA. Contrast-enhanced CT at six months showed complete resorption of the ascending aortic intramural hematoma, and 64-multislice CT at one year showed a descending aortic intramural hematoma. The patient is doing well one year after the onset. This is a rare case of successful medical treatment for acute type A aortic dissection complicated with AMI.

A novel echocardiographic index of inefficient left ventricular contraction resulting from mechanical dyssynchrony

OBJECTIVES The purpose of this study was to explore the possibility of using our novel echocardiographic index of inefficient left ventricular (LV) contraction in patient selection for cardiac resynchronization therapy (CRT). METHODS Forty consecutive patients with LV ejection fraction < or = 35% were divided into 2 groups, 9 CRT candidates and 31 non-CRT candidates based on conventional criteria. A global LV time-area curve and regional LV time-area curves in 6 radial sectors were obtained using two-dimensional echocardiography in the short-axis view with speckle tracking. Fractional inefficient contraction (FIC, %) was calculated as follows: (1-global LV area change/sum of regional LV area changes) x 100. LV dyssynergy and dyssynchrony were quantified as the standard deviations of minimal values of circumferential speckle-tracking strain and their timings in the 6 sectors, respectively. RESULTS There was no significant difference in LV dyssynchrony between CRT candidates and non-CRT candidates (79 + or - 61 ms vs. 58 + or - 26 ms, respectively). In contrast, FIC was significantly larger in CRT candidates than in non-CRT candidates (15.7 + or - 11.0% vs. 5.4 + or - 3.5%, respectively, p=0.0018), with less overlap between groups. FIC showed a positive correlation with dyssynchrony (r=0.64) and a negative correlation with dyssynergy (r=-0.42). CONCLUSIONS Our novel echocardiographic index of inefficient LV contraction, which increases with more dyssynchrony or less dyssynergy, may prove more useful in patient selection for CRT than other indices that focus on LV temporal dyssynchrony alone.

Mechanisms of changes in functional mitral regurgitation by preload alterations

BACKGROUND This study aimed to investigate the mechanisms of acute changes in functional mitral regurgitation (FMR) by preload alterations. METHODS Twenty-two consecutive patients with left ventricular ejection fraction <40% and at least mild FMR underwent transthoracic echocardiography. Passive leg lifting and sublingual administration of nitroglycerin were performed to alter preload. Mitral regurgitant volume (MRV) was assessed using the Doppler method. RESULTS MRV changed in parallel with preload alterations. MRV correlated better with tenting height (TH) than with mitral annular area (MAA) at baseline, whereas the difference in the correlate coefficients was not statistically significant (R=0.69 and R=0.40, respectively; p=0.19). On the other hand, changes in MRV between each sequential stage correlated better with those in MAA than with those in TH (R=0.68 and R=0.44, respectively; p=0.043). Multiple regression analysis revealed that baseline TH was the independent determinant of baseline MRV (R=0.69, p=0.0004), whereas changes in MAA with preload alteration were the independent determinant of the changes in MRV (R=0.68, p<0.0001). Changes in left atrial (LA) volume were the independent determinant of the changes in MAA (R=0.30, p=0.0063). CONCLUSIONS Acute changes in FMR with preload alterations resulted from the transverse changes in MAA rather than the longitudinal changes in tethering-tenting of mitral geometry, and mitral annular deformation was determined by changes in LA volume. Preload reduction might help heart failure treatment through the reduction in FMR resulting from the decrease in LA and mitral annular size.

Prediction of aortic stenosis-related events in patients with systolic ejection murmur using pocket-sized echocardiography

BACKGROUND We have previously reported the usefulness of our newly developed visual aortic stenosis (AS) score in screening for AS using pocket-sized echocardiography. The objective of this study was to investigate whether the visual AS score and/or conventional aortic valve calcification score derived from pocket-sized echocardiography can be used to predict AS-related events. METHODS One hundred and nine patients with systolic ejection murmur (SEM) or known AS (64 males, age 75±9 years) were enrolled and a visual AS score and an aortic valve calcification score were assessed using pocket-sized echocardiography. The primary endpoint was defined as AS-related events, including cardiac death and aortic valve replacement, during the follow-up period. RESULTS In a multivariate Cox proportional hazards analysis, AS-related events were independently predicted by an aortic valve calcification score ≥3 (HR, 3.5; 95% CI, 1.1-11; p=0.033) and a visual AS score ≥3 (HR, 15; 95% CI, 1.8-125; p=0.013). During 18±9 months of follow-up, the event-free survival rate was 98% in patients with both a visual AS score <3 and an aortic valve calcification score <3, 90% in patients with either a visual AS score ≥3 or an aortic valve calcification score ≥3 (p<0.0001), and 62% in patients with both a visual AS score ≥3 and an aortic valve calcification score ≥3 (p<0.0001). CONCLUSIONS The combination of visual AS score and aortic valve calcification score derived from pocket-sized echocardiography is useful for predicting AS-related events in patients with SEM.

Early Detection of Abnormal Left Atrial and Left Ventricular Coupling, Using Two-dimensional Speckle Tracking Echocardiography in Patients with Preserved Left Ventricular Ejection Fraction

Aims: The aim of this study was to detect the abnormalities of left atrial (LA)-left ventricular (LV) coupling using two-dimensional speckle tracking echocardiography in patient with preserved LV ejection fraction. Methods: A total of 177 asymptomatic patients with preserved LV ejection fraction were studied. Global LV longitudinal peak strain (GLS) and peak LA longitudinal strain during systole (PALS) were measured. The ratio of E/Ea to PALS was used as an index of LA stiffness. Results: The patients were classified into 2 groups according to the GLS: impaired group (n=81; GLS>-18%) and normal group (n=96; GLS≤-18%). Both GLS and PALS were reduced in the impaired group (p<0.001). LA stiffness was increased in the impaired group (p<0.05). In the normal group, there was no significant correlation between GLS and LA volume index. There was no significant correlation between GLS and LA stiffness. In the impaired group, GLS significantly correlated with correlated with the LA stiffness (r=0.50, p<0.001). Similarly, GLS significantly correlated with LA volume index (r=0.36, p<0.001). Original Research Article Ohara et al.; CA, 5(4): 1-9, 2016; Article no.CA.29072 2 Conclusions: In patients with preserved longitudinal LV systolic function, LA structure and function are preserved. However, LA structure and function are rapidly impaired in patients with reduced longitudinal LV systolic function. LV longitudinal systolic dysfunction may cause the LA wall to become stiffer rapidly.