[Show abstract][Hide abstract] ABSTRACT: Background
: Left atrial appendage (LAA) dysfunction predisposes patients with atrial fibrillation (AF) to cardioembolic stroke. Two-dimensional (2D) speckle tracking was reported to be useful for evaluating left atrial (LA) regional function, as well as left ventricular function. However, it remains unclear whether 2D speckle tracking is useful for evaluating LAA dysfunction. Therefore, we investigated whether decreased LA strain may predict LAA dysfunction and thrombus formation in patients with acute ischemic stroke.
We performed transthoracic and transesophageal echocardiography in 120 patients (83 males, mean age 72 ± 11 years) within 7 days of onset of an acute ischemic stroke. Longitudinal LA strain was evaluated using 2D speckle tracking imaging at each LA segment, and peak systolic strain was calculated by averaging the results for each segment.
Forty-eight patients had LAA dysfunction as defined by the presence of LAA thrombus and/or severe spontaneous echo contrast. LA peak systolic strain was significantly decreased in patients with LAA dysfunction compared to those without (32.3 ± 13.7% vs. 12.1 ± 7.2%, p < 0.0001). LA peak systolic strain was significantly correlated with LAA emptying flow velocity (r = 0.693, p < 0.0001). The optimum LA peak systolic strain cut off value for predicting LAA dysfunction was 19%. Multivariate logistic regression analysis showed that LA peak systolic strain was an independent predictor of LAA dysfunction (odds ratio 0.059, 95% confidence interval 0.018-0.146; p < 0.0001).
Decreased LA peak systolic strain was independently associated with LAA dysfunction in patients with acute ischemic stroke.
Biochimica et Biophysica Acta - Clinical 12/2014; 2. DOI:10.1016/j.bbacli.2014.09.004
[Show abstract][Hide abstract] ABSTRACT: Background
Thioredoxin-1 (Trx-1) is an abundant 12.5 kDa redox protein expressed in almost all eukaryotic cells that protect against the development of heart failure and kidney dysfunction. Plasma Trx-1 levels are considered as a reliable marker for oxidative stress. However, it remains to be determined whether plasma Trx-1 levels can predict cardiac prognosis in patients with chronic heart failure (CHF).
Methods and results
We measured plasma Trx-1 levels and urinary β2-microglobulin–creatinine ratio (UBCR), a marker for renal tubular damage, in 156 consecutive patients with CHF and 17 control subjects. The patients were prospectively followed for a median follow-up period of 627 days and 46 cardiac events were observed. The patients with cardiac events had significantly higher plasma Trx-1 levels and UBCR levels than the cardiac event-free patients. Multivariate Cox proportional hazard analysis revealed that an elevated Trx-1 level was independently associated with poor outcome in patients with CHF after adjustment for confounding factors (hazard ratio, 1.74; 95% confidence interval, 1.33–2.29; p < 0.0001). UBCR was increased with higher plasma Trx-1 levels. Kaplan–Meier analysis demonstrated that the highest Trx-1 tertile was associated with the highest risk of cardiac events.
Plasma Trx-1 level was associated with renal tubular damage and cardiac prognosis, suggesting that it could be a useful marker to identify patients at high risk for comorbid heart failure and renal tubular damage.
Journal of Cardiology 11/2014; 64(5). DOI:10.1016/j.jjcc.2014.02.016 · 2.78 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A 14-year-old patient was diagnosed with hypertrophic cardiomyopathy associated with Wolff-Parkinson-White syndrome. The two-dimensional speckle tracking strain method showed normal left ventricular local contraction, but the peak systolic longitudinal strain of the right ventricular (RV) anterior wall was earlier than that of the septal wall. As expected, the location of the accessory pathway was at the RV anterior wall. The patient's RV local contraction was normalized by successful radiofrequency application.
Internal Medicine 07/2014; 53(14):1527-30. DOI:10.2169/internalmedicine.53.2019 · 0.90 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: It is well known that left atrial appendage (LAA) dysfunction plays an important role in the occurrence of cardioembolic stroke. The atrium is the main source of brain natriuretic peptide (BNP) in patients with atrial fibrillation (AF). We hypothesized that the plasma BNP level would be a sensitive predictor of LAA dysfunction in patients with acute ischemic stroke.
Transesophageal echocardiography was performed and plasma BNP levels were measured in 223 patients (145 males, age 69 ± 14 years), within 7 days after the onset of acute ischemic stroke. None of the patients had a history of congestive heart failure. LAA thrombus was detected in 23 of 77 (30%) patients with AF. Plasma BNP levels were markedly higher in patients with cardioembolic stroke compared to those without (144 pg/ml vs. 35 pg/ml, p<0.05). Plasma BNP levels were significantly correlated with LAA emptying flow velocity regardless of sinus rhythm (R=-0.352) or AF (R=-0.436). Furthermore, among patients with cardioembolic stroke, plasma BNP levels were markedly higher in patients with cardiogenic stroke, as diagnosed by transesophageal echocardiography, than in those with cryptogenic stroke (193 pg/ml vs. 14 pg/ml, p<0.05). Multivariate logistic regression analysis showed that a BNP concentration >90 pg/ml was an independent predictor of cardiogenic stroke (odds ratio 41.39, 95% confidence interval 1.28-138; p=0.0358).
Elevated plasma BNP concentrations may be a reliable surrogate marker for the prediction of LAA dysfunction and cardiogenic stroke in patients with acute ischemic stroke.
Journal of Cardiology 04/2012; 60(2):126-32. DOI:10.1016/j.jjcc.2012.02.010 · 2.78 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: It is important to evaluate left atrial appendage (LAA) dysfunction for primary and secondary prevention of stroke in patients with atrial fibrillation (AF). LAA dysfunction can reportedly be evaluated by LAA wall velocity (LAWV) measured by transthoracic echocardiographic (TTE) imaging. The aim of this study was to examine whether TTE-LAWV can predict long-term cerebrovascular events in patients with ischemic stroke with AF.
TTE imaging and transesophageal echocardiographic imaging were performed <7 days after onset in 179 consecutive patients with stroke with AF. TTE-LAWV was measured using Doppler tissue imaging at the LAA tip from the parasternal short-axis view on TTE imaging, as previously reported. All patients were followed up prospectively.
Cerebrovascular events were defined as cerebrovascular death and/or recurrent ischemic stroke requiring hospitalization. There were 32 cerebrovascular events during a median follow-up period of 397 days. TTE-LAWV was significantly lower in patients with cerebrovascular events than in patients without (8.3 ± 2.8 vs 11.3 ± 4.0 cm/sec, P < .01). Cox multivariate hazard analysis showed that low TTE-LAWV (<8.7 cm/sec) was an independent predictor of cerebrovascular events (hazard ratio, 3.460; P < .05). Kaplan-Meier analysis showed that cerebrovascular event rates were significantly higher in patients with low TTE-LAWV (<8.7 cm/sec) compared with those with high TTE-LAWV (34% vs 7%, P < .01).
Impaired LAA function was associated with long-term cerebrovascular events in patients with stroke with AF. TTE-LAWV may be a feasible parameter for risk stratification in patients with AF.
Journal of the American Society of Echocardiography: official publication of the American Society of Echocardiography 02/2012; 25(5):576-83. DOI:10.1016/j.echo.2012.01.012 · 4.06 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A patient with cardiac sarcoidosis showed low R-wave amplitude in the entire right ventricle (RV). To troubleshoot this, a left ventricular (LV) lead was implanted in the coronary vein. The pace/sense terminal of the defibrillation lead was connected to LV:IS-1 of the defibrillator. Conversely, the LV lead was connected to RV:IS-1. Induced ventricular fibrillation was successfully terminated without any undersensing.
[Show abstract][Hide abstract] ABSTRACT: Left atrial volume index (LAVI) is known to reflect the duration and severity of increased left atrial pressure caused by left ventricular (LV) diastolic dysfunction. However, the prognostic value of LAVI in patients with heart failure (HF) has not been fully investigated.
Transthoracic echocardiography was performed in 146 consecutive patients (78 men, 68 women; mean age 72 ± 12 y) who were hospitalized for HF. There were 45 cardiac events (32%) during a median follow-up period of 448 days. There were no significant differences in LV end-diastolic dimensions or ejection fraction between patients who did or did not have cardiac events. However, LAVI was markedly higher in patients with, than those without, cardiac events (56 ± 26 vs 44 ± 22 mL/m(2); P < .01). Kaplan-Meier analysis showed that there was a stepwise increase in risk of cardiac events with each increment of LAVI category, and LAVI >53.3 mL/m(2) correlated with the highest risk of cardiac events (log-rank test; P < .01). Multivariate Cox proportional hazard analysis showed that high LAVI was an independent predictor for cardiac events (hazard ratio 1.427; 95% confidence interval 1.024-1.934; P < .05).
LAVI may be useful for stratification of risk in patients with HF.
[Show abstract][Hide abstract] ABSTRACT: Atrial fibrillation is associated with ischemic stroke because of thrombi that form within the left atrial appendage (LAA). The aim of this study was to develop a new parameter for LAA function that is easily performed using transthoracic echocardiography (TTE).
TTE and transesophageal echocardiography were performed in 106 patients with stroke. LAA wall motion velocity (TTE-LAWV) was measured using Doppler tissue imaging at the LAA tip.
TTE-LAWV was significantly lower in patients with atrial fibrillation and LAA thrombus than in those with atrial fibrillation and no LAA thrombus and in sinus rhythm (7.5 +/- 1.9 vs 10.0 +/- 3.4 and 13.8 +/- 5.7 cm/s, respectively, P < .05). TTE-LAWV was significantly correlated with LAA emptying flow velocity (R = 0.462, P < .05). The multivariate logistic regression analysis showed that TTE-LAWV < 8.7 cm/s was an independent predictor of LAA thrombus formation (odds ratio, 9.473; 95% confidence interval, 1.172-76.55; P < .05).
TTE-LAWV can noninvasively evaluate LAA dysfunction and assist in the detection of LAA thrombus.
Journal of the American Society of Echocardiography: official publication of the American Society of Echocardiography 03/2010; 23(5):545-552.e1. DOI:10.1016/j.echo.2010.02.006 · 4.06 Impact Factor