Wei Feng Shen

Prognostic significance of Doppler-derived left ventricular diastolic filling variables in dilated cardiomyopathy

To determine the prognostic significance of pulsed wave Doppler-derived left ventricular diastolic filling velocity profiles and the relationship between Doppler variables and clinical functional status, the follow-up outcomes of 62 consecutive patients with dilated cardiomyopathy and symptoms of left ventricular dysfunction were analyzed. All patients had echocardiographic left ventricular end-diastolic dimension > or = 6.0 cm, fractional shortening < 25%, increased E pointseptal separation, and diffuse hypokinesia or akinesia. During a mean follow-up period of 30.5 +/- 13.9 months, 27 patients experienced cardiac events: 23 died of either progressive pump failure or an episode of sudden death and four required cardiac transplantation because of refractory heart failure. Peak early filling velocity (78 +/- 23 cm/sec vs 65 +/- 25 cm/sec; p < 0.03) was higher and late atrial filing velocity (34 +/- 13 cm/sec vs 55 +/- 19 cm/sec; p < 0.001) was lower in patients with cardiac events than in cardiac event-free survivors. The ratio of early to late transmitral filling velocities was higher (2.6 +/- 1.2 vs 1.5 +/- 1.3; p < 0.001), and the deceleration time of early diastole was shorter (133 +/- 48 msec vs 175 +/- 71 msec; p < 0.001) in patients with cardiac events. The cardiac event rate was significantly higher in patients with an early to late filling velocity ratio greater than 2 (77% vs 19%; p < 0.001) or a deceleration time less than 150 msec (58% vs 23%; p < 0.05) than in those without. Stepwise multivariate regression analysis revealed that the pattern of transmitral early to late filling velocity ratio was the only significant independent Doppler echocardiographic predictor of outcome for these patients. Repeat Doppler echocardiographic examinations, which were performed in 31 survivors after intensive treatment (mean, 38.6 +/- 6.5 months), showed that early filling velocity was decreased (55 +/- 20 cm/sec vs 75 +/- 25 cm/sec; p < 0.02), late atrial filling velocity was increased (74 +/- 27 cm/sec vs 57 +/- 21 cm/sec; p < 0.01), early to late filling velocity ratio was reduced (0.8 +/- 0.3 vs 1.7 +/- 1.3; p < 0.001), and deceleration time was prolonged (227 +/- 60 msec vs 167 +/- 82 msec; p < 0.01) in 18 patients with clinical functional improvement, whereas these measurements were unaltered in the remaining 13 patients whose functional status was unchanged or had deteriorated.(ABSTRACT TRUNCATED AT 400 WORDS)

Quantitation of aortic valve area in aortic stenosis with multiplane transesophageal echocardiography: Comparison with monoplane transesophageal approach

The accuracy and reliability of two-dimensional monoplane and multiplane transesophageal echocardiography (TEE) in the quantitation of aortic valve area were compared in 54 patients with aortic stenosis. Fifty patients had aortic valve area calculated by the continuity equation and transthoracic Doppler echocardiography (TTE); 25 underwent cardiac catheterization. Two-dimensional echocardiograms adequate for quantitation of aortic valve area were obtained in 21 (39%) patients with monoplane TEE and in 51 (94%) with multiplane TEE. The mean aortic valve area determined by both TEE methods did not differ significantly from that derived from TTE and catheterization. The mean difference of aortic valve area measurements between monoplane TEE and TTE was -0.045 +/- 0.11 cm2; that between multiplane TEE and TTE was 0.001 +/- 0.11 cm2. Multiplane TEE provided a better correlation of aortic valve area measurements with either TTE (y = 0.97 x + 0.03; r = 0.96; SEE = 0.11 cm2) or catheterization (y = 0.84 x + 0.11; r = 0.90; SEE = 0.12 cm2) than the monoplane TEE (y = 0.88 x + 0.13; r = 0.83; SEE = 0.15 cm2 and y = 0.41 x + 0.42; r = 0.81; SEE = 0.15 cm2). Severe aortic stenosis with valve orifice area of < or = 0.75 cm2 during TTE examination was found by multiplane TEE with a sensitivity of 96% and a specificity of 96%. Thus aortic valve area can be directly and reliably measured by two-dimensional multiplane TEE in majority of patients with aortic stenosis.

Noninvasive prediction of coronary artery disease by transesophageal echocardiographic detection of thoracic aortic plaque in valvular heart disease

Clinical and angiographic features and transesophageal echocardiographic (TEE) findings were retrospectively analyzed in 105 consecutive patients with valvular heart disease to assess the value of TEE detection of thoracic aortic plaque for predicting coronary artery disease. In 19 patients with significant coronary artery stenosis (> or = 70% narrowing of the luminal diameter in the left anterior descending, left circumflex, or right coronary arteries, or > or = 50% stenosis of the left main coronary artery), 18 had thoracic aortic plaque on TEE study. In contrast, aortic plaque existed in only 10 of the remaining 86 patients with normal coronary arteries or mildly atherosclerotic coronary lesions. The presence of aortic plaque on TEE study had a sensitivity of 95% and a specificity study had a sensitivity of 95% and a specificity of 88% for significant coronary stenosis at angiography. The positive and negative predictive values were 64% and 99%, respectively. There was a close relation between the degree of aortic intimal changes and the severity of coronary artery disease (r = 0.65; p < 0.001). Multivariate stepwise regression analysis of patient age, sex, risk factors of cardiovascular disease, angina, and TEE findings revealed that atherosclerotic aortic plaque was the most significant independent predictor of coronary artery disease. This study indicates that TEE detection of atherosclerotic plaque in the thoracic aorta is useful in the noninvasive prediction of the presence and severity of coronary artery disease in patients with valvular heart disease.

Clinical Significance of Intracavitary Spontaneous Echo Contrast in Patients with Dilated Cardiomyopathy

To assess the occurrence rate and major determinants of spontaneous echo contrast and to examine its impact on thromboembolic events and mortality in patients with dilated cardiomyopathy, 86 hospitalized patients (73 men and 13 women, mean age 63 +/- 11 years) with dilated cardiomyopathy who underwent transthoracic and transesophageal echocardiographic examinations were followed up for a mean of 20 +/- 13 months. Spontaneous echo contrast was observed in 36 patients (42%) and was detected only with the transesophageal approach. It was seen in the left atrium in 33 patients, in both right and left atria in 1 patient, in both left atrium and left ventricle in 1 patient, and in the descending aorta in 1 patient. Spontaneous echo contrast was more frequent in the presence of atrial fibrillation (p < 0.05), left atrial enlargement (p < 0.02) and severely depressed left ventricular function (p < 0.01), but was less common in patients with moderate to severe mitral regurgitation (p < 0.05). This imaging phenomenon was the only significant independent predictor of intracardiac thrombus formation and previous and subsequent thromboembolic events. During follow-up, there were 26 deaths, and survival in patients with spontaneous echo contrast was significantly lower than in those without it (p < 0.02). A spontaneous echo contrast is commonly detected with transesophageal echocardiography in patients with dilated cardiomyopathy especially in the presence of atrial fibrillation, left atrial enlargement and severe left ventricular dysfunction. This imaging phenomenon represents an important marker for thromboembolic risk and may influence the treatment and clinical outcome of these patients.

Beneficial effect of residual flow to the infarct region on left ventricular volume changes after acute myocardial infarction

To determine the relationship between alterations in left ventricular (LV) volumes and residual flow to the infarct region after myocardial infarction (MI), 57 patients with a first acute transmural MI underwent two-dimensional echocardiography within 48 hours of infarction and after 1 month. A reduction in ST segment elevation by greater than or equal to 35% of the peak value of ST segment elevation within the initial 6 hours was used as an indirect indicator for early reperfusion of the infarct-related artery (IRA). IRA patency and collateral circulation were assessed by coronary arteriography performed at 1 month. LV volumes increased in patients with a persistent ST segment elevation within the initial 6 hours of infarction and in those with a totally occluded IRA without collaterals. However, LV volumes were unchanged in patients with early reperfusion and in those who had subtotally occluded IRA or who had collateral circulation. LV dilation (greater than or equal to 20% increase in end-diastolic volume) occurred less often when early reperfusion and angiographically patent IRA or collateral supply to the infarct zone were present. This prospective study indicates that residual flow to the infarct region may exert a beneficial effect on LV volume changes after acute MI.