Mitral Valve Early Systolic Billowing Induces Following Annular Expansion and Leaflet Augmentation in Barlow's Disease: Sequential Analysis using Three-dimensional Echocardiography.

AIMS: Although systolic expansion of the annulus has been recognized in Barlow's disease, the mechanisms of the unique pathological movement of the annulus and its relation to the leaflet augmentation has not yet been clarified. We aimed to investigate the detailed mechanisms of the characteristic mitral apparatus dynamics in Barlow's disease by frame-by-frame sequential geometric analysis using real-time three-dimensional transesophageal echocardiography. METHODS AND RESULTS: Fifty-three patients with Barlow's disease and severe mitral regurgitation without torn chordae, as well as 10 controls, were included. We evaluated geometric changes in the mitral complex using three-dimensional transesophageal echocardiography at five points during systole. To identify early systolic billowing of leaflets, the annulo-leaflet angle was measured. We also performed a more detailed analysis in four consecutive frames just before and after leaflet free-edge prolapse above the annulus plane. The median annulo-leaflet angle of both leaflets in early systole was greater than 0° (above annulus plane) in patients with Barlow's disease, and billowing of the leaflet body were observed from early systole. The prolapse volume of both leaflets increased markedly from early to mid-systole (1.60 [0.85-2.80] to 4.00 [2.10-6.45] mL; analysis of variance, p < 0.001; post-hoc, p < 0.05). With frame-by-frame analysis, dynamic augmentation of the annulus and leaflets developed between frames just before and just after leaflet free-edge prolapse (analysis of variance, p < 0.01; post-hoc, p < 0.05). CONCLUSIONS: In Barlow's disease, early systolic billowing of the mitral leaflet induces systolic annulus expansion followed by leaflet augmentation and leaflet free-edge prolapse.

Prevalence and predictive factors for clinical outcomes of isolated functional tricuspid regurgitation.

BACKGROUND: A substantial number of patients have functional tricuspid regurgitation (TR). Isolated functional TR has been undertreated and may be a next target for transcatheter intervention. However, the prevalence, patient characteristics, and predictive factors for prognosis remain unclear. METHODS: From patients in our echocardiographic database (N = 64,242), we extracted those with severe TR and examined prognosis according to etiologies of TR. Thereafter, we focused on two types of isolated functional TR; progressive TR after left-sided valve surgery (postoperative TR) and TR associated with annular dilatation (atrial TR). Composite adverse events were defined as all-cause death or hospitalization for heart failure (HF). RESULTS: Of 1001 patients with severe TR (median age, 77 years; female, 58 %), 71 (7 %) patients were classified as postoperative TR, and 149 (15 %) as atrial TR. During the follow-up period (median, 1.6 years), 30 composite adverse events were observed (postoperative TR, n = 14; atrial TR, n = 16). Composite adverse events were less frequent in these two types of functional TR than TR of other etiologies. Multivariate analysis adjusted for age and sex showed that a history of hospitalization for HF, history of cardiac surgery >2 times, loop diuretics, estimated glomerular filtration rate, blood urea nitrogen, hemoglobin, platelet level, left ventricular ejection fraction, and right ventricular dimension were associated with clinical adverse events (p < 0.05), while B-type natriuretic peptide level was not. CONCLUSIONS: A considerable number of patients had isolated functional TR. Extracardiac factors such as renal function, hemoglobin and platelet are important in determining clinical outcomes.

Case series of mobile structures detected vividly by using superb microvascular imaging.

Background: Superb microvascular imaging (SMI) is a new imaging technique that can reveal low-velocity blood flow without use of a contrast agent. SMI is based on an original algorithm and effectively removes tissue motion artifacts (clutter motion) from the background, thereby preserving visibility of low-velocity blood flow. SMI is expected to be useful for the evaluation of heart diseases, as well as blood vessels. Case summary: Here, we report three cases in which a mobile structure in the heart or a blood vessel was detected easily by strong enhancement on SMI. In the heart, the entire mass was strongly enhanced by colour-SMI and had the appearance of 'a fire ball'. In the abdominal aorta and carotid artery, SMI captured a strongly enhanced echo image of a mass and revealed hyperechoic mobile plaque. It was hard to detect with the conventional echocardiography. Discussion: It is important to detect mobile intravascular and intracardiac structures as they are risk factors of thrombosis. Echo images are often strongly affected by the skill of the examiner, the patient's body habitus, and the presence of intestinal gas; thus, it is often difficult to detect a small mass with conventional echocardiography. With the use of SMI, even small mobile structures can be displayed at high intensity in comparison with the surrounding blood flow. Therefore, the non-invasive SMI was useful for the detection of mobile intravascular and intracardiac structures. Our findings of the current report may lead to new developments in SMI for imaging in the cardiac region.

Substitute parameters of exercise-induced pulmonary hypertension and usefulness of low workload exercise stress echocardiography in mitral regurgitation.

In asymptomatic patients with mitral regurgitation (MR), data of exercise-induced pulmonary hypertension (EIPH) are limited, and feasibility of evaluating EIPH is not high. We aimed to investigate prognostic impact of EIPH and its substitute parameters. Exercise stress echocardiography (ESE) were performed in 123 consecutive patients with moderate to severe degenerative MR. The endpoint was a composite of death, hospitalization for heart failure, and worsening of symptoms. EIPH [tricuspid regurgitation peak gradient (TRPG) at peak workload ≥ 50 mmHg] was shown in 57 patients (46%). TRPG at low workload was independently associated with TRPG at peak workload (ß = 0.67, p < 0.001). Early surgical intervention (within 6 months after ESE) was performed in 65 patients. Of the remaining 58 patients with the watchful waiting strategy, the event free survival was lower in patients with EIPH than in patients without EIPH (48.1 vs. 97.0% at 1-year, p < 0.001). TRPG at low workload ≥ 35.0 mmHg as well as EIPH were associated with poor prognosis in patients with the watchful waiting strategy. In conclusion, the importance of ESE and evaluating EIPH in patients with MR was re-acknowledged. TRPG at peak workload can be predicted by TRPG at low workload, and TRPG at low workload may be useful in real-world clinical settings.

Diagnostic value of vena contracta area measurement using three-dimensional transesophageal echocardiography in assessing the severity of aortic regurgitation.

PURPOSE: Transthoracic echocardiography (TTE) provides noninvasively quantitative assessment of aortic regurgitation (AR) severity, but its diagnostic accuracy depends on image quality. Two-dimensional transesophageal echocardiography (TEE) is a semi-invasive procedure that is excellent in evaluating AR mechanism. However, quantitative assessment may be challenging due to restrictions in probe manipulation. This study aimed to investigate the diagnostic value of three-dimensional TEE to measure the vena contracta area (3DVCA) of AR. METHODS: The subjects comprised 62 patients (age, 65 ± 16 years) whose AR was evaluated using TEE. The 3DVCA and semi-quantitative TEE parameters, such as the ratio of AR jet width to left ventricular outflow tract (jet/LVOT) and the vena contracta width (VCW) of AR jet, were compared using angiography grade and quantitative TTE measurements including regurgitant volume (RVol) and effective regurgitant orifice area (EROA). The diagnostic accuracy was determined using receiver operating characteristic (ROC) analysis, and the reproducibility of 3DVCA was also evaluated. RESULTS: In 3DVCA, less overlap between angiography grades were observed. Correlation with RVol or EROA was better in 3DVCA than in Jet/LVOT or VCW. The area under the ROC curve was .737 for jet/LVOT, .773 for VCW, and .849 for 3DVCA, respectively. The optimal cutoff value of 3DVCA was ≥.31 cm2 for grading severe AR. Inter- and intra-observer reproducibility of 3DVCA were .92 and .97, respectively. CONCLUSIONS: The 3DVCA method using TEE showed high diagnostic accuracy and reproducibility. 3DVCA deserves use in accurately assessing AR severity, especially in patients who present difficulty in quantitative Doppler assessment using TTE.

Comparison of Clinical Characteristics, Natural History and Predictors of Disease Progression in Patients With Degenerative Mitral Stenosis Versus Rheumatic Mitral Stenosis.

Mitral annular calcification (MAC) is a common echocardiographic finding and an increasingly recognized cause of degenerative mitral stenosis (DMS). However, little is known about the clinical characteristics and disease progression in DMS, particularly in comparison with rheumatic mitral stenosis (RMS). We retrospectively reviewed 203 consecutive patients with mitral stenosis (113 with DMS and 90 with RMS) who underwent echocardiography at our institution between January 2014 and December 2017. We compared the clinical characteristics and disease progression between the 2 groups. In addition, we analyzed the predictors of disease progression (defined as annual progression rate of a mean gradient >0 mm Hg/year) among patients with DMS. Patients with DMS were significantly older and had higher prevalence of atherosclerotic comorbidities than those with RMS. During the median follow-up period of 2.2 years, the annual progression rates were comparable (0.8 ± 0.8 mm Hg/year in DMS vs 1.0 ± 1.2 mm Hg/year in RMS; p = 0.32) and were highly variable (0.0 to 3.5 mm Hg/year in DMS and 0.0 to 5.5 mm Hg/year in RMS) within both groups among disease progression. In DMS patients, atherosclerotic comorbidities and lower initial mean gradient were significantly associated with disease progression even after adjustment by age and sex. There was no significant difference in the disease progression according to the circumferential MAC severity determined by echocardiography among DMS. In conclusion, DMS disease progression was slow but highly variable, similar to that of RMS. In patients with DMS, the baseline MAC severity did not correlate with disease progression, suggesting the importance of follow-up echocardiography regardless of the MAC severity.

Prevalence, determinants, and prognostic significance of exercise-induced pulmonary hypertension in patients with hypertrophic cardiomyopathy.

Exercise-induced pulmonary hypertension (EIPH) is associated with worse outcomes in patients with heart failure or valvular heart disease. However, little is known regarding the implications of EIPH in hypertrophic cardiomyopathy (HCM) patients. We retrospectively reviewed data of consecutive HCM patients who underwent clinically indicated exercise echocardiography using a semi-supine bicycle ergometer at our hospital. EIPH was defined as pulmonary artery systolic pressure ≥ 60 mmHg during exercise. The incidences of HCM-related mortality and HCM-related morbidity during follow-up period were evaluated. Of 42 patients (mean age 59 ± 21 years; 4 with resting obstruction, 19 with provoked obstruction, and 19 without obstruction), 16 (38%) developed EIPH. Patients with EIPH had significantly longer resting E wave deceleration time (271 ± 116 vs. 213 ± 66 ms; P = 0.04), higher resting pulmonary artery systolic pressure (35 ± 6 vs. 31 ± 5 mmHg; P = 0.04), and higher B-type natriuretic peptide level (283 [222, 465] vs. 142 [54, 423] pg/ml; P = 0.04) than those without EIPH. Kaplan-Meier curve analysis demonstrated that EIPH was significantly associated with HCM-related morbidity (log-rank; P = 0.01). In Cox regression analysis, EIPH was a significant predictor of HCM-related morbidity (hazard ratio: 5.98, 95% confidence interval 1.36-41.07; P = 0.02). In conclusion, EIPH was documented in about one-third of HCM patients. EIPH was a significant predictor of HCM-related morbidity in patients with HCM.