Transesophageal Doppler color flow mapping assessment of atrial septal defect

Transesophageal Doppler color flow imaging was performed in 19 adult patients (mean age 35 years) with an atrial septal defect demonstrated by cardiac catheterization or at surgery, or both. The transesophageal study correctly identified and classified 19 of 19 shunts in contrast to 16 of 18 shunts identified by the transthoracic approach. The area of the atrial septal defect was calculated by assuming it to be circular and taking the maximal Doppler color flow jet width at the defect site as its diameter. The pulsed Doppler sample volume was placed parallel to the shunt flow direction at the defect site to obtain the mean velocity and flow duration. From these values, the shunt volume was calculated as a product of the defect area, mean velocity, flow duration and heart rate. The calculated shunt flow volume obtained by transesophageal study showed a good correlation with shunt flow volume (r = 0.91, p less than 0.001) and pulmonary to systemic blood flow ratio (r = 0.84, p less than 0.001) obtained at cardiac catheterization. The size of the defect by transesophageal Doppler color flow mapping correlated fairly well with the size estimated at surgery (r = 0.73, p = 0.004). It is concluded that transesophageal Doppler color flow imaging is useful in the detection and classification of atrial septal defects and in the assessment of shunt volumes.     

Application of Doppler color flow imaging to determine valve area in mitral stenosis.

This study was undertaken to examine whether Doppler color flow imaging could accurately estimate the valve area in mitral stenosis. Doppler color flow assessments were performed in both an in vitro model and in 30 patients with mitral stenosis undergoing cardiac catheterization. In the experimental Doppler study using a circuit model, color jet width correlated well with actual orifice diameter (r = 0.99). In the clinical Doppler study, the mitral valve orifice was assumed to be elliptic and the mitral valve area was calculated from the following equation: (pi/4) (a x b), where a = color jet width at the mitral valve orifice in the apical long-axis view (short diameter) and b = the width in the 90 degrees rotated view (long diameter). Mitral valve area was also determined by two-dimensional echocardiography and the pressure half-time method, and the results for all three noninvasive methods were compared with those obtained at cardiac catheterization. By Doppler color flow imaging, mitral valve area could be determined in all patients and there was a significant correlation between the Doppler jet and catheterization estimates of mitral valve area (r = 0.93). Valve area determined by two-dimensional echocardiography correlated well with catheterization measurements in 26 patients (r = 0.84). However, the area could not be determined in 4 (13%) of the 30 patients because of technical problems. Although there was a fair correlation between the valve area determined by the pressure half-time method and catheterization (r = 0.79), this method tended to overestimate valve area in patients with aortic regurgitation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Transatrial septal velocity measurement by Doppler echocardiography in atrial septal defect: correlation with Qp:Qs ratio

Right atrial velocities measured perpendicular to the atrial septum by Doppler echocardiography in patients with atrial septal defects (ASD) have a discernible morphology that may bear a relation to shunt magnitude. The integral of the right atrial Doppler waveform was compared with shunt magnitude measured at cardiac catheterization or nuclear shunt scan in 17 ASD patients. For control subjects, the mean right atrial velocity was 15 +/- 4 cm/s (+/- standard deviation) and that for ASD patients was 41 +/- 11 cm/s (p less than 0.001). Doppler pulmonary-to-systemic flow ratio (Qp:Qs) correlated with catheterization Qp:Qs ratio (n = 9, r = 0.85, SEE = 0.27) and with nuclear Qp:Qs ratios (n = 8, r = 0.60, SEE = 0.51). Mean transatrial septal velocity in ASD patients correlated with catheterization Qp:Qs ratio (n = 9, r = 0.8, SEE = 6.0) and with simultaneous Doppler Qp:Qs ratio (n = 16, r = 0.89, SEE = 4.9, y = 16.2 +/- 8.3). Although Qp:Qs ratio can be approximated by measuring pulmonary and systemic flow by Doppler echocardiography in many ASD patients, this newly described method allows estimation of Qp:Qs ratio. It is useful when these more conventional measurements cannot be performed because of turbulence or when inadequate imaging prevents Doppler pulmonary to systemic flow measurement.     

Doppler color flow mapping in the evaluation of prosthetic mitral and aortic valve function

Doppler color flow mapping and color-guided conventional Doppler studies were performed on 119 patients with 126 prosthetic valves (mitral alone in 60, aortic alone in 52 and both mitral and aortic in 7 patients) within 2 weeks of the catheterization study or surgery, or both. The mean pressure gradients derived by color-guided continuous wave Doppler ultrasound correlated well with those obtained at catheterization for both the tissue and mechanical mitral and aortic prostheses (r = 0.85 to 0.87). For the effective prosthetic orifice areas, better correlation with catheterization results were obtained with the tissue mitral (r = 0.94) and tissue aortic (r = 0.87) prostheses than with the mechanical mitral (r = 0.79) and mechanical aortic (r = 0.76) prostheses. The maximal width of the color flow signals at their origin from the tissue mitral prostheses also correlated well with the effective prosthetic orifice area at catheterization (r = 0.81). Doppler color flow mapping identified prosthetic valvular regurgitation with a sensitivity and specificity of 89% and 100%, respectively, for the mitral and 92% and 83% for the aortic prostheses. There was complete agreement between the Doppler color flow mapping and angiographic grading of the severity of prosthetic valvular regurgitation in 90% of mitral and 73.5% of the aortic regurgitant prostheses with under- or overestimation by greater than 1 grade in only two cases. Valvular and paravalvular regurgitation was correctly categorized by Doppler color flow mapping in relation to the surgical findings in 94% of the mitral and 80.5% of the aortic prostheses.     

Color-guided Doppler echocardiographic assessment of aortic valve stenosis

The severity of valvular aortic stenosis was assessed by Doppler color flow mapping in 100 consecutive patients who underwent successful cardiac catheterization within 2 weeks of the Doppler study. The maximal width of the aortic stenosis jet seen in 61 of these patients (Group A) was measured at the aortic valve. Color-guided continuous wave Doppler examination was used to measure the mean transaortic pressure gradient, and the aortic valve area was estimated using the simplified continuity equation. The aortic stenosis jet was not seen in 39 patients (Group B), and the mean pressure gradient and aortic valve area in these patients were assessed by conventional Doppler echocardiography alone. The mean pressure gradient obtained by continuous wave Doppler study and cardiac catheterization in the 61 Group A patients correlated well (r = 0.90); the correlation was lower in the 39 Group B patients (r = 0.70). The overall correlation for the combined Groups A and B was good (r = 0.82). The aortic valve area estimated by continuous wave Doppler study and cardiac catheterization in 54 Group A patients correlated well (r = 0.92); the correlation in 22 Group B patients was lower (r = 0.71). The correlation for all 76 patients (Groups A and B) was good (r = 0.80). The maximal aortic stenosis jet width also correlated well with the aortic valve area estimated at catheterization in 54 patients (r = 0.90). Group C represented an additional 14 patients in whom the left ventricle could not be entered during cardiac catheterization.(ABSTRACT TRUNCATED AT 250 WORDS)     

彩色多普勒血流显像对心房间隔缺损诊断的评价

目的：探讨彩色多普勒超声心动图诊断心房间隔缺损的临床价值。方法：以彩色多普勒血流显像技术对７５例患者的心房间隔缺损定位及估测缺损大小，并测定肺动脉收缩压。结果：７５例患者中，５２例经手术证实。彩色多普勒超声心动图诊断心房间隔缺损的敏感性达１００％；对缺损的定位准确率为９４．２％（４９／５２）；对缺损大小的估测与手术结果呈显著正相关（ｒ＝０．９５，Ｐ＜０．００１）。对Ｍ型超声心动图显示疑有肺动脉高压的２３例患者用三尖瓣反流压差法估测的肺动脉收缩压与心导管测值密切相关（ｒ＝０．８８，Ｐ＜０．００１）；同时计算肺动脉与主动脉根部内径比值与心导管测值比较，发现肺动脉与主动脉根部内径比值≥１．３５，提示肺动脉高压。结论：彩色多普勒超声心动图对心房间隔缺损有术前诊断价值，并能评价手术效果，可替代有创性检查。     

Two-dimensional echocardiography and Doppler color flow mapping in the diagnosis and prognosis of ventricular septal rupture

Doppler color flow mapping in conjunction with two-dimensional echocardiography was used to evaluate ventricular septal rupture after myocardial infarction (seven anterior and eight inferior) in 15 patients and to correlate these findings with cardiac catheterization and surgical or autopsy data. Ventricular septal rupture was diagnosed by turbulent flow traversing the ventricular septum. The direction and velocity of shunt flow was determined by color M-mode and conventional Doppler methods. In all patients, Doppler color flow mapping correctly defined the site of septal rupture, which occurred at areas of discordant septal wall motion or "hinge points" (six posterior inlet, three anterior inlet, and six apical trabecular septum). Each of three patients with moderate tricuspid regurgitation and three of four patients with right-to-left shunting during diastole died, and all had an elevated right ventricular end-diastolic pressure. Right ventricular wall motion index was significantly higher in the patients who died compared with those who survived (mean +/- SEM; 2.8 +/- 0.2 vs. 2.0 +/- 0.2, p = 0.012), but there was no difference in left ventricular wall motion index. The rupture size measured by Doppler color flow imaging (1.7 +/- 0.1 cm) correlated with the size determined during surgery or autopsy (1.8 +/- 0.2 cm, r = 0.68, p = 0.022) and the pulmonic-to-systemic shunt flow ratio by cardiac catheterization (2.4:1 +/- 0.3, r = 0.74, p = 0.004). Color-guided continuous-wave Doppler estimates of right ventricular systolic pressure (47 +/- 2 mm Hg) correlated with cardiac catheterization measurements (48 +/- 3 mm Hg, r = 0.90, p = 0.0002).(ABSTRACT TRUNCATED AT 250 WORDS)     

A new method for noninvasive estimation of ventricular septal defect shunt flow by Doppler color flow mapping: imaging of the laminar flow convergence region on the left septal surface

An accurate but simple and noninvasive method for quantifying flow across a ventricular septal defect has yet to be implemented for routine clinical use. A region of flow convergence is commonly imaged by Doppler color flow mapping on the left septal surface of the ventricular septal defect, appearing as a narrowed region of laminar flow with aliased flow velocities entering the orifice. If the first aliasing region represents a hemispheric isovelocity boundary of a surface of flow convergence and all flow at this surface crosses the ventricular septal defect, the flow through the defect can be estimated by using the radius (R), measured from the first alias to the orifice, and the Nyquist limit (NL) velocity (the flow velocity at the first alias). Doppler color flow imaging was performed in 18 children with a single membranous ventricular septal defect undergoing cardiac catheterization at a mean age of 29.8 months (Group I). Indexes of maximal flow rate across the defect were developed from either the radius or the area, obtained by planimetry, of the first alias, based on Doppler color flow images. All indexes were corrected for body surface area and compared with shunt flow (Qp-Qs) and pulmonary to systemic flow ratio (Qp/Qs) determined at cardiac catheterization. Doppler color flow indexes derived from images of flow convergence in both the long-axis (n = 15) and oblique four-chamber (n = 10) views correlated closely with Qp/Qs (r = 0.71 to 0.92) and Qp - Qs (r = 0.69 to 0.97).(ABSTRACT TRUNCATED AT 250 WORDS)     

Utility of Doppler echocardiography in the evaluation of aortic homograft valved conduit function in children: need for segmental conduit interrogation

To assess the utility of Doppler echocardiography in evaluation of aortic homograft valved conduit function, 10 consecutive pediatric patients had Doppler examination of aortic homograft valved conduits associated with follow-up cardiac catheterization. General correlation was found between the Doppler-derived peak systolic pressure gradient across the aortic homograft valved conduit and cardiac catheterization (r = 0.65, P less than 0.05, SEE = 20.5). One patient with multilevel obstruction had significant underestimation of gradient by Doppler due to incomplete segmental interrogation of the aortic homograft valved conduit. For the other nine patients with complete segmental conduit interrogation, correlation between Doppler and cardiac catheterization was excellent (r = 0.93, P less than 0.01, SEE = 10). Conduit insufficiency in nine out of ten patients was graded qualitatively using Doppler color flow mapping with excellent correlation between color flow mapping and cardiac catheterization (r s = 98). Aortic homograft valved conduit function can be accurately noninvasively assessed by Doppler but proximal, valve, and distal conduit segmental interrogation is necessary to localize site of obstruction if present, rule out multilevel obstruction, and avoid underestimation of systolic gradient.     

Transesophageal Doppler echocardiography in the diagnosis of atrial septal defect

To assess the usefulness of transesophageal Doppler echocardiography (TEE) in diagnosing atrial septal defect (ASD), we studied eight cases with secundum type ASD, in which the diagnosis was confirmed by cardiac catheterization and surgery. In all cases, TEE provided clear images of the interatrial septum with its defect. Shunt flow through the defect was observed by color Doppler technique, and its velocity was measured using the FFT mode. In two cases, right-to-left shunt blood flow was detected. Two types of probes were used in this study, a lateral scanning probe and a longitudinal scanning probe. The scanning plane of the former was perpendicular to the axis of the probe, and that of the latter was parallel to it. The two probes facilitated the measurement of the two right-angled dimensions, with which we could calculate the defect area, assuming the defect to be an ellipse. The volume of a left-to-right shunt was obtained by multiplying the defect area by the integration of flow velocity against time. Shunt volume per cardiac cycle obtained by this method correlated well with that obtained by the Fick's method during cardiac catheterization. In six cases without a right-to-left shunt, the coefficient of correlation was 0.98, and in all eight cases it was reduced to 0.72. Thus, we concluded that TEE is useful for diagnosing and evaluating ASD.     

Severity of aortic stenosis assessed by Doppler techniques

Continuous wave (CW) Doppler ultrasound has facilitated accurate estimates of pressure gradient (PG) across a stenotic valve. However, the severity of stenosis cannot be assessed using PG alone because it is dependent on actual flow across the valve. In this study, Doppler techniques were used to predict PG and aortic valve areas (AVA) in adults with aortic stenosis (AS). Fifty-four adult patients undergoing cardiac catheterization for suspected AS were prospectively evaluated. There were 28 men and 26 women, who ranged in age from 25 to 68 years with a mean of 56 years. These Doppler ultrasound studies were performed using a 2 MHz transducer and an Aloka SSD-730. With CW Doppler ultrasound, the highest velocities of the aortic jet were recorded from an apical approach. Left ventricular outflow flows were recorded about 1.0-1.5 cm below the aortic annulus using high PRF. Doppler waveforms were analyzed for the AT/ET (AT: acceleration time, ET: ejection time), and Doppler PG was calculated from the maximum velocity (V) of the aortic jet based on a modified Bernoulli equation (PG = 4V2), and aortic valve area was obtained using the continuity equation-(AVA = left ventricular outflow tract stroke volume divided by AS jet velocity integral). These data were compared with hemodynamic data obtained from cardiac catheterization. The following results were obtained: 1. In eight patients with substantial aortic regurgitation, whose maximum catheter PG were from 20 to 45 mmHg, the AT/ET was less than 0.30. The ratio of AT/ET correlated with the peak velocity of the aortic jet (r = 0.88) and the maximum PG (r = 0.87) obtained from cardiac catheterization. 2. In 46 patients with AS, the maximum PG by CW Doppler showed an excellent correlation with maximum catheterization PG (r = 0.97, SEE 6 mmHg), and the mean PG as calculated by the two techniques also disclosed a good correlation (r = 0.97, SEE 5.4 mmHg).(ABSTRACT TRUNCATED AT 400 WORDS)     

Accuracy of prospective two-dimensional/Doppler echocardiography in the assessment of reparative surgery

Between January 1987 and January 1989, all 129 patients (aged 11 days to 25 years, median 39 months) undergoing both an echocardiographic examination and cardiac catheterization after reparative surgery were prospectively included in a study to assess the accuracy of combined two-dimensional and Doppler color flow imaging. The patient diagnoses were transposition of the great arteries (n = 20), tetralogy of Fallot (n = 38), coarctation of the aorta (n = 24), complete atrioventricular (AV) canal (n = 15), atrial septal defect (n = 8), ventricular septal defects (n = 3), pulmonary stenosis (n = 4), aortic stenosis (n = 8) and subaortic stenosis (n = 9). In arterial tract stenosis, there was high correlation between Doppler estimates and catheterization-derived measurements of residual right ventricular outflow tract obstruction in patients after the arterial switch operation for transposition of the great arteries (r = 0.95) as well as in patients after corrective repair of tetralogy of Fallot (r = 0.84). In semilunar/AV valve regurgitation, graded as none, mild, moderate or severe, echocardiographic estimates correlated exactly with angiographic grading in 84% and differed by one angiographic grade in the other 16%. In residual left to right shunting, no hemodynamically significant shunt was missed by echocardiography. For residual shunts at the ventricular level (n = 32), addition of Doppler color flow imaging improved the sensitivity (from 63% to 94%) and the negative predictive value (from 88% to 98%). In elevated right ventricular pressure, Doppler-derived right ventricular-right atrial pressure estimates in 24 patients correlated well with catheterization measurements (r = 0.93). Combined two-dimensional and Doppler color flow echocardiography was highly accurate in the prospective evaluation of these four types of postoperative residual.     

Prediction of the site and severity of obstruction in hypertrophic cardiomyopathy by color flow mapping and continuous wave Doppler echocardiography.

OBJECTIVE. We investigated whether the site and severity of an obstruction in hypertrophic cardiomyopathy can be accurately predicted by the combined use of color-coded and continuous wave Doppler echocardiography. BACKGROUND. Predicting the site of obstruction by end-systolic cavity shape is not reliable. Therefore, hemodynamic localization of the obstruction is required before surgery is performed. Such localization should be possible with color flow imaging, which provides two-dimensional velocity mapping reflecting the distribution of pressures within the left ventricle. Discrepancies in assessment of the pressure gradient by Doppler echocardiography and cardiac catheterization (which are usually not performed simultaneously) may be due to spontaneous variation of the dynamic obstruction in addition to technical factors related to both methods. METHODS. Twenty consecutive patients with hypertrophic cardiomyopathy were examined 1 day before transseptal left heart catheterization. The obstruction site was defined by color flow mapping. The pressure gradient was determined by continuous wave Doppler echocardiography. Measurements were also performed simultaneously in 10 patients during cardiac catheterization. RESULTS. Midventricular obstruction was correctly identified in 4 patients and subvalvular obstruction in 15 patients. One patient had no obstruction at rest. Invasively and noninvasively determined pressure gradients correlated well (r = 0.89, SEE = 16.3 mm Hg). Multiple single-beat analysis in 10 patients, also simultaneously examined with Doppler echocardiography and catheterization, yielded an excellent correlation (r = 0.97, SEE = 13.1 mm Hg). Comparing the simultaneous (r = 0.96, SEE = 12.5 mm Hg) and nonsimultaneous (r = 0.81, SEE = 23.8 mm Hg) recordings in these patients, we found that the spontaneous variation of the dynamic obstruction mainly accounted for discrepancies (p less than 0.05). CONCLUSION. The combined use of color-coded and continuous wave Doppler echocardiography provides the relevant hemodynamic information required for decision-making in patients with hypertrophic cardiomyopathy who are considered for transaortic myectomy.     

Diagnosis and quantitative evaluation of secundum-type atrial septal defect by transesophageal Doppler echocardiography

Transesophageal echocardiography (horizontal sector scan) was performed in 11 patients with secundum atrial septal defect (ASD). In all 11 patients, transesophageal echocardiography presented the definite visualization of the defect and a clear laminar shunt flow that showed its 2 peaks in late systole and late diastole. We estimated the size of ASD and a shunt volume across the defect by using transesophageal echocardiography. The defect size determined by transesophageal echocardiography was correlated with the surgical measurement (horizontal width, r = 0.92, p less than 0.001; vertical length, r = 0.85, p less than 0.01). A significant high correlation was shown between the shunt volume measured by transesophageal echocardiography and that by Fick's method (r = 0.87, p less than 0.01). There was no significant correlation between the pulmonary to systemic flow volume (ratio) and the mean shunt flow velocity across ASD, although a high linear correlation was observed between the pulmonary to systemic flow ratio and the defect size in horizontal direction (r = 0.82, p less than 0.01). Transesophageal echocardiography used for diagnosis and quantitative evaluation of ASD could be performed easily and satisfactorily within 10 minutes. Thus, transesophageal echocardiography is a useful method in evaluation of the defect size and the shunt flow volume of ASD. The mean shunt flow velocity was not a reliable index for estimating the shunt flow volume. The defect size might be a valuable determinant of left-to-right shunt volume in ASD.     

Doppler assessment of interventricular pressure gradient across isolated ventricular septal defect

Continuous wave Doppler ultrasound was used to estimate the pressure gradient between the right and left ventricle for assessment of pulmonary arterial systolic pressure in 30 patients with isolated ventricular septal defect and for subsequent comparison with similar data obtained on cardiac catheterization. The age of the patients ranged from 8 months to 45 years (6.8 +/- 8.6 years). No patient had right or left ventricular outflow tract obstruction. Doppler measurements were done within 24 h of cardiac catheterization. Pressure gradient across ventricular septal defect on cardiac catheterization ranged from 7 to 95 mmHg (48 +/- 24 mmHg) and that on Doppler assessment ranged from 8 to 78 mmHg (42 +/- 20 mmHg). Doppler measurements of interventricular pressure gradient correlated well with those obtained on cardiac catheterization (r = 0.90, p less than 0.001). Correlation was better in patients with pressure gradient across ventricular septal defect less than 75 mmHg (r = 0.96). Correlation was poor in three of five patients with very small ventricular septal defects (interventricular pressure gradient greater than 75 mmHg) because the jet used was not ideal. Thus continuous wave Doppler ultrasound is an accurate noninvasive means of measuring pressure gradient across ventricular septal defect, which is a useful parameter for assessment of pulmonary artery systolic pressure in patients with isolated ventricular septal defect without right and left ventricular outflow tract obstruction.     

Prospective Doppler echocardiographic evaluation of pulmonary artery diastolic pressure in the medical intensive care unit

To test the hypothesis that the noninvasive evaluation of pulmonary regurgitation can provide accurate estimates of pulmonary artery (PA) diastolic pressures and PA wedge pressures, Doppler echocardiographic studies were performed immediately before bedside PA catheterization in 29 medical intensive care unit patients. The characteristic color flow Doppler signal of pulmonary regurgitation was detected in 19 (66%) patients. In 17 of the 29 patients (59%), the gradient between the right ventricle and PA at end-diastole could be calculated from the pulsed-wave Doppler signal of pulmonary regurgitation using the simplified Bernoulli equation. Right atrial pressure was then estimated by examination of the jugular venous pulse or by electronic transduction of the pressure signal from a previously placed central venous catheter. A noninvasive estimate of PA diastolic pressure was made by adding the clinical estimate of right atrial pressure to the end-diastolic pressure gradient across the pulmonary valve. Pulmonary artery catheterization was then performed and stripchart recordings were interpreted by a physician who was unaware of the noninvasively-estimated PA diastolic pressure. The PA diastolic pressure estimated by Doppler echocardiography correlated closely with that found at catheterization (r = 0.94, mean absolute difference 3.3 mm Hg). The noninvasive estimate of PA diastolic pressure also correlated with the PA wedge pressure (r = 0.87, mean absolute difference 3.8 mm Hg). Therefore, in 59% of medical intensive care unit patients, Doppler echocardiographic evaluation of pulmonary regurgitation allowed accurate noninvasive estimation of PA diastolic pressure.     

Noninvasive determination of pulmonary arterial systolic pressure by continuous wave Doppler

We evaluated the accuracy of continuous wave Doppler for estimating pulmonary arterial systolic pressure in patients with tricuspid regurgitation. Of 44 patients with a variety of cardiac disorders, 39 (89%) had Doppler-detected tricuspid regurgitation. Adequate spectral profiles of the flow signals were obtained in 34 of them (87%), representing 77% of the entire group. Continuous wave Doppler ultrasound was used to measure the maximum velocity of the regurgitant jet, and by applying the modified Bernoulli equation, the systolic pressure gradient between the right ventricle and the right atrium was calculated. Pulmonary arterial systolic pressure was estimated by adding the transtricuspid gradient to the mean right atrial pressure, and correlated well with catheterization values (r = 0.96). The correlation coefficient was not significantly modified if mean right atrial pressures were excluded in the calculations (r = 0.91). Continuous wave Doppler constitutes a sensitive method for the detection of tricuspid regurgitation. The method using the tricuspid gradient provides an accurate estimation of pulmonary arterial systolic pressure. Combined with other available methods (pulsed wave Doppler), this noninvasive technique can yield information comparable with that obtained at catheterization.     

Determination of the stenotic aortic valve area in adults using Doppler echocardiography

The severity of aortic stenosis was evaluated by Doppler echocardiography in 48 adults (mean age 67 years) undergoing cardiac catheterization. Maximal Doppler systolic gradient correlated with peak to peak pressure gradient (r = 0.79, y = 0.63x + 25.2 mm Hg) and mean Doppler gradient correlated with mean pressure gradient (r = 0.77, y = 0.59x + 10.0 mm Hg) by manometry. The transvalvular pressure gradient is flow dependent, however, and associated left ventricular dysfunction was common in our patients (33%). Thus, of the 32 patients with an aortic valve area less than or equal to 1.0 cm2 at catheterization, 6 (19%) had a peak Doppler gradient less than 50 mm Hg. To take into account the influence of volume flow, aortic valve area was calculated as stroke volume, measured simultaneously by thermodilution, divided by the Doppler systolic velocity integral in the aortic jet. Aortic valve areas calculated by this method were compared with results at catheterization in the total group (r = 0.71). Significant aortic insufficiency was present in 71% of the population. In the subgroup without significant coexisting aortic insufficiency, closer agreement of valve area with catheterization was noted (n = 14, r = 0.91, y = 0.83x + 0.24 cm2). Transaortic stroke volume can be determined noninvasively by Doppler echocardiographic measures in the left ventricular outflow tract, just proximal to the stenotic valve. Aortic valve area can then be calculated as left ventricular outflow tract cross-sectional area times the systolic velocity integral of outflow tract flow, divided by the systolic velocity integral in the aortic jet.(ABSTRACT TRUNCATED AT 250 WORDS)     

Continuous wave Doppler assessment of patients subjected to pulmonary balloon valvoplasty

To evaluate the role of Doppler ultrasound in accurately quantitating patients with valvar pulmonary stenosis, we studied 30 patients (20 patients undergoing balloon pulmonary valvoplasty before and after the procedure, and 10 patients who had previously undergone pulmonary balloon valvoplasty) by Doppler echocardiography and cardiac catheterization. The peak systolic gradient was calculated by the two methods within 24 hours of each other. The maximal velocity of blood flow was obtained by non-imaging, continuous wave Doppler ultrasound examination performed from various parasternal and subcostal positions and the valve gradient was calculated using a modified Bernoulli's equation. Transpulmonary peak systolic gradient calculated by Doppler examination ranged from 9 to 159 mm Hg (mean 54.8 +/- 34.5 mm Hg) and correlated well with values obtained at cardiac catheterization (r = 0.94, P less than 0.001). Thus our study shows that accurate quantification of pulmonary valve stenosis can be reliably undertaken non-invasively utilizing Doppler echocardiography.     

Ratio of early transmitral velocity to lateral mitral annular early diastolic velocity has the best correlation with wedge pressure following cardiac surgery.

BACKGROUND: Although previous investigators reported that mitral annular velocity predicts mean pulmonary capillary wedge pressure (PCWP), it is unknown whether the lateral or septal mitral annular velocity more faithfully predicts PCWP after cardiac surgery. METHODS AND RESULTS: To assess the effect of cardiac surgery on the predictive values for PCWP by measuring mitral annular velocity, 52 consecutive patients undergoing cardiac surgery were studied. All patients underwent transthoracic echocardiography and right-sided cardiac catheterization both before and after surgery. The peak early diastolic velocity of transmitral flow (E) was measured by pulsed-wave Doppler and the peak early diastolic velocities of the lateral (LEa) and septal (SEa) mitral annulus by pulsed-wave tissue Doppler imaging. The ratios of E to LEa (E/LEa) and SEa (E/SEa) were calculated. Immediately after echocardiography, PCWP was measured using a balloon-tipped pulmonary artery catheter. After surgery, LEa was significantly increased (6.4+/-2.7 vs 8.6+/-3.3 cm/s, p<0.001), but SEa was unchanged (6.0+/-2.5 vs 5.5+/-2.3 cm/s, p=0.09). E/LEa correlated well with PCWP both before and after surgery (r=0.79 and r=0.69, respectively, p<0.001). Although E/SEa correlated well before surgery (r=0.67, p<0.001), it correlated only weakly after surgery (r=0.44, p<0.01). CONCLUSIONS: E/LEa has the best correlation with PCWP both before and after cardiac surgery and may be more useful than E/SEa in the noninvasive estimation of PCWP.