Noninvasive estimation of pulmonary artery diastolic pressure in patients with tricuspid regurgitation by Doppler echocardiography.

OBJECTIVES: The purpose of this study was to determine whether Doppler echocardiographic assessment of right ventricular pressure at the time of pulmonary valve opening could predict pulmonary artery diastolic pressure. BACKGROUND: Doppler echocardiography has been used to estimate right ventricular systolic pressure noninvasively. Because right ventricular and pulmonary artery diastolic pressure are equal at the time of pulmonary valve opening, Doppler echocardiographic estimation of right ventricular pressure at this point might provide an estimate of pulmonary artery diastolic pressure. METHODS: We studied 31 patients who underwent right heart catheterization and had tricuspid regurgitation. Pulmonary flow velocity was recorded by pulsed wave Doppler echocardiography, and tricuspid regurgitant velocity was recorded by continuous wave Doppler echocardiography. The time of pulmonary valve opening was determined as the onset of systolic flow in the pulmonary artery. Tricuspid velocity at the time of pulmonary valve opening was measured by superimposing the interval between the onset of the QRS complex on the ECG and the onset of pulmonary flow on the tricuspid regurgitant envelope. The tricuspid gradient at this instant was calculated from the measured tricuspid velocity using the Bernoulli equation. This gradient was compared to the pulmonary artery diastolic pressure obtained by right heart catheterization. MEASUREMENTS AND RESULTS: The pressure gradient between the right atrium and right ventricle obtained at the time of pulmonary valve opening ranged from 9 to 31 mm Hg (mean, 19+/-5) and correlated closely with invasively measured pulmonary artery diastolic pressure (range, 9 to 36 mm Hg; mean, 21+/-7 mm Hg; r = 0.92; SEE, 1.9 mm Hg). CONCLUSION: Doppler echocardiographic measurement of right ventricular pressure at the time of pulmonary valve opening is a reliable noninvasive method for estimating pulmonary diastolic pressure.     

Noninvasive estimation of both systolic and diastolic pulmonary artery pressure from Doppler analysis of tricuspid regurgitant velocity spectrum in patients with chronic heart failure

Background Noninvasive estimation of pulmonary artery systolic and diastolic pressures usually requires the investigation of both tricuspid and pulmonary regurgitant jets and an estimate of right atrial pressure. A new, noninvasive method to obtain pulmonary diastolic pressure (based on the hemodynamic demonstration that right ventricular systolic pressure and pulmonary artery diastolic pressure are equal at the time of pulmonary valve opening) from the analysis of tricuspid regurgitation alone has been described in a small cohort of patients. We sought to verify the accuracy of this method in a large population of patients with heart failure. Methods An estimate of pulmonary artery diastolic pressure was obtained by transposing the pulmonary opening time (from the onset of the R wave on the electrocardiographic tracing to the beginning of pulmonic forward flow on Doppler examination) onto the tricuspid regurgitant velocity curve and calculating the pulmonary artery diastolic pressure value as the pressure gradient between the right ventricle and right atrium at this time. The study group included 86 consecutive patients (64 men, aged 52 ± 11 years) with heart failure (New York Heart Association class ≥II, 94%) who were in stable clinical condition with a chiefly idiopathic (57%), ischemic (24%), or other form (13%) of dilated cardiomyopathy. Noninvasive, right-sided pressures were compared with invasive measurements obtained during right heart catheterization performed within 24 hours. The Bland and Altman graphic method was used together with the calculation of the Lin concordance correlation coefficient and its 95% CI to assess the agreement between hemodynamic and echocardiographic measurements. Results Catheter-derived pulmonary artery systolic pressure ranged from 8 to 119 mm Hg (mean 42 ± 21 mm Hg), pulmonary artery diastolic pressure from 1 to 59 mm Hg (mean 20 ± 11 mm Hg), and right atrial pressure from −5 to 20 mm Hg (mean 6 ± 5 mm Hg). Tricuspid regurgitation was detected in 75 of 86 patients (87%). Pulmonary artery systolic pressure ranged from 13 to 110 mm Hg (mean 44 ± 21 mm Hg); the pressure gradient between the right ventricle and right atrium at time t of the pulmonary valve opening on the tricuspid regurgitation velocity curve was measurable in 70 of 75 (93%) cases and ranged from 3.5 to 64 mm Hg (mean 22 ± 11 mm Hg). Good agreement was observed not only for pulmonary artery systolic pressure but also for pulmonary artery diastolic pressure, based on the analysis of the tricuspid regurgitation velocity jet, with a slight difference between measurements (−1.8 and 0.1, respectively), no evident pattern of point scattering, and a high concordance correlation coefficient that was elicited by the virtually total overlapping of lines on the graph. Overall results were not significantly different whether patients with depressed right ventricular function (right ventricular ejection fraction ≤35%), with a tricuspid regurgitation grade ≥2 and atrial fibrillation were included in the analysis. Conclusions The narrow paired difference for the estimate of pulmonary artery systolic pressure and the even better difference for pulmonary artery diastolic pressure using the tricuspid regurgitation velocity curve analysis indicates that this new method reliably estimates invasive right-sided pressures over a wide range of pressure values in patients with heart failure. The overall good correlation with invasive values indicates that Doppler examination of tricuspid regurgitation alone may provide a simple and comprehensive new method for the noninvasive evaluation of right ventricular and pulmonary hemodynamics in patients with heart failure. (Am Heart J 2002;144:1087-94.)     

Quantitative assessment of pulmonary hypertension in patients with tricuspid regurgitation using continuous wave Doppler ultrasound

Doppler ultrasound examination was performed in 69 patients with a variety of cardiopulmonary disorders who were undergoing bedside right heart catheterization. Patients were classified into two groups on the basis of hemodynamic findings. Group I consisted of 20 patients whose pulmonary artery systolic pressure was less than 35 mm Hg and Group II consisted of 49 patients whose pulmonary artery systolic pressure was 35 mm Hg or greater. Tricuspid regurgitation was detected by Doppler ultrasound in 2 of 20 Group I patients and 39 of 49 Group II patients (p less than 0.001). Twenty-six of 27 patients with pulmonary artery systolic pressure greater than 50 mm Hg had Doppler evidence of tricuspid regurgitation. In patients with tricuspid regurgitation, continuous wave Doppler ultrasound was used to measure the velocity of the regurgitant jet, and by applying the Bernoulli equation, the peak pressure gradient between the right ventricle and right atrium was calculated. There was a close correlation between the Doppler gradient and the pulmonary artery systolic pressure measured by cardiac catheterization (r = 0.97, standard error of the estimate = 4.9 mm Hg). Estimating the right atrial pressure clinically and adding it to the Doppler-determined right ventricular to right atrial pressure gradient was not necessary to achieve accurate results. These findings indicate that tricuspid regurgitation can be identified by Doppler ultrasound in a large proportion of patients with pulmonary hypertension, especially when the pulmonary artery pressure exceeds 50 mm Hg. Calculation of the right ventricular to right atrial pressure gradient in these patients provides an accurate noninvasive estimate of pulmonary artery systolic pressure.     

Accurate measurement of the transmitral gradient in patients with mitral stenosis: A simultaneous catheterization and Doppler echocardiographic study

Objectives. This study compared the accuracy of Doppler echocardiography with that of conventional cardiac catheterization in the measurement of transmitral gradients in patients with mitral stenosis.Background. Simultaneous measurement of left atrial and left ventricular pressures is the most accurate method for determination of the mean mitral valve gradient in patients with mitral stenosis. Because of the inherent risks of transseptal catheterization, pulmonary capillary wedge pressure has been used in many invasive laboratories for determination of the mean mitral valve gradient. Recent studies have observed significant errors when pulmonary capillary wedge pressure was used for these measurements. Doppler echocardiography provides a noninvasive alternative for measurement of the transmitral gradient, but its relative accuracy has remained unclear.Methods. Seventeen patients with mitral stenosis who underwent transseptal cardiac catheterization had simultaneous measurement of 1) transmitral gradient by direct left atrial and left ventricular pressures, 2) transmitral gradient by pulmonary capillary wedge and left ventricular pressures, and 3) transmitral gradient by Doppler echocardiography.Results. Transmitral gradient measured by pulmonary capillary wedge and left ventricular pressures significantly overestimated the gradient obtained by direct measurement of left atrial pressure, with a mean (±SD) difference of 3.3 ± 3.5 mm Hg (or 53%). Correcting the pulmonary capillary wedge pressure for the phase shift resulted in better correlation, but a consistent overestimation still remained, with a mean difference of 2.5 ± 2.9 mm Hg (or 43%). The best correlation with the smallest variability was comparison of the Doppler-derived mean gradient with the gradient from direct measurement of left atrial and left ventricular pressures, with a mean difference of 0.2 ± 1.2 mm Hg.Conclusions. Compared with the transmitral gradient obtained by direct measurement of left atrial and left ventricular pressures, the Doppler-derived gradient is more accurate than that obtained by conventional cardiac catheterization and should be considered the reference standard.     

Pulmonary artery diastolic pressure: a simultaneous Doppler echocardiography and catheterization study

Pulmonary hypertension is an important determinant of the clinical presentation of and surgical approach to patients with heart disease. To confirm the utility of continuous wave Doppler echocardiography in assessing the pulmonary artery diastolic pressure in patients with pulmonary regurgitation, 51 patients representing the wide hemodynamic spectrum of pulmonary artery pressure underwent simultaneous determination of pulmonary artery diastolic pressure by continuous wave Doppler echocardiography and cardiac catheterization. Pulmonary artery diastolic pressure was estimated from the Doppler recordings by the end-diastolic pressure gradient obtained by the modified Bernoulli equation plus the estimated right atrial pressure. A correlation was observed (r = 0.935, SEE = 7.4 mmHg) between Doppler and catheterization pulmonary artery diastolic pressure. In addition, comparison between the mean diastolic pressure gradient across the pulmonary valve by Doppler and pulmonary artery diastolic pressure at catheterization yielded a high correlation (r = 0.947, SEE = 5.1 mmHg). These data demonstrate that continuous wave Doppler echocardiography is a useful noninvasive technique for evaluating the pulmonary artery diastolic pressure in patients with pulmonary regurgitation.     

Noninvasive assessment of hemodynamic subsets in patients with acute myocardial infarction using digital color Doppler velocity profile integration and pulmonary venous flow analysis

Four major hemodynamic subsets from cardiac index (CI) and mean pulmonary artery (PA) wedge pressure with a PA catheter usually reflect clinical status and prognosis of patients with acute myocardial infarction (AMI). Recently, a new color Doppler technique has been developed for automated cardiac output measurements (ACOM). Color Doppler echocardiography also provides noninvasive estimation of PA wedge pressure from pulmonary venous (PV) flow analysis. This study evaluates the value of ACOM and PV flow analysis by color Doppler echocardiography for the assessment of hemodynamic subsets in patients with AMI. We performed ACOM and PV flow analysis by color Doppler echocardiography in 55 patients with AMI who underwent hemodynamic assessment with a PA catheter. From both noninvasive and invasive methods, we classified hemodynamic subsets as follows: subset I: normal hemodynamics (CI >2.2 L/min/m2, PA wedge pressure < or =18 mm Hg); subset II: pulmonary congestion (CI >2.2 L/min/m2, PA wedge pressure >18 mm Hg); subset III: peripheral hypoperfusion (CI < or =2.2 L/min/m2, PA wedge pressure < or =18 mm Hg); and subset IV: pulmonary congestion and peripheral hypoperfusion (CI < or =2.2 L/min/m2, PA wedge pressure >18 mm Hg). Doppler assessment of hemodynamic subsets was possible in 50 of 55 patients (91%). CI from ACOM correlated well with that from the thermodilution method (r = 0.94) with close agreement. There was a good correlation between the systolic fraction (systolic velocity-time integral expressed as a fraction of the sum of systolic and diastolic velocity-time integrals) of PV flow and PA wedge pressure measured from cardiac catheterization (r = -0.83). When we determined the value of 45% in the systolic fraction as the cut-off point in predicting >18 mm Hg in PA wedge pressure, there was 90% (45 of 50 patients) agreement between noninvasive and invasive hemodynamic subsets. Thus, ACOM and PV flow analysis by color Doppler echocardiography is useful in the noninvasive assessment of hemodynamic subsets in patients with AMI.     

Estimation of pulmonary vascular resistance with Doppler diastolic gradients

This study was undertaken to determine the diastolic Doppler echocardiographic correlates of pulmonary vascular resistance calculated on cardiac catheterization in patients with secondary pulmonary arterial hypertension. Thirty-eight consecutive patients with congenital heart disease, pulmonary artery hypertension and pulmonary regurgitation were studied. Continuous-wave Doppler-derived pulmonary artery diastolic gradients were measured at 3 points on the pulmonary regurgitant diastolic velocity slope: peak diastolic, end-diastolic (at the R wave on the electrocardiogram), and mid-diastolic (midway between the peak and end-diastolic points). Catheterization data included oximetry, measurements of pressure in the cardiac chambers and great arteries, and calculation of pulmonary vascular resistance index. Doppler-derived peak, mid, and end-diastolic pulmonary regurgitation gradients correlated best with catheterization-measured pulmonary artery systolic, mean and diastolic pressures, respectively. The best Doppler correlate of pulmonary vascular resistance index was the pulmonary artery end-diastolic gradient. Clinically useful information can be obtained from Doppler pulmonary artery diastolic gradients measured on the pulmonary regurgitant diastolic velocity slope, which can estimate the pulmonary arterial pressure as well as pulmonary vascular resistance obtained on cardiac catheterization.     

Noninvasive Estimation of Diastolic Pulmonary Artery Pressure by Doppler Analysis of Tricuspid Regurgitation Velocity in Pediatric Patients

Purpose. Diastolic pulmonary artery pressure (dPAP) is equal to right ventricular pressure at the time of pulmonary valve opening. We studied the accuracy of dPAP estimated from Doppler profile of tricuspid regurgitation (TR) jet in pediatric patients. Methods. Echocardiograms were prospectively performed on consecutive pediatric heart transplant recipients undergoing right‐heart catheterization and endomyocardial biopsy. An estimate of dPAP was obtained by superimposing the pulmonary valve opening time, indexed to the electrocardiogram, onto the TR Doppler tracing. Echocardiographic estimates of dPAP from end‐diastolic pulmonary regurgitation (PR) were obtained for comparison. Catheter‐derived right atrial pressure was added to the Doppler gradient in both groups. Doppler estimates and catheter‐derived measurements of dPAP were compared using Lin correlation and Bland–Altman analysis. Results. Sixty‐five catheterization studies were performed on 35 patients (20 males): median age at enrollment: 12.1 years (4 months to 18 years); median time: since transplant of 1.2 years (21 days to 16.1 years). Adequate TR signal was obtained in a significantly higher proportion of patients than an adequate PR signal (65% vs. 43%, respectively, P= .007). Median catheter‐derived dPAP was 12 mm Hg (6–30 mm Hg) and right atrial pressure was 6 mm Hg (1–17 mm Hg). Median estimated dPAP from TR was 15 mm Hg (range: 7–29 mm Hg), with the Lin correlation coefficient of 0.74 (95% confidence interval [CI]: 0.6–0.87). Median estimate for dPAP from PR was 10 mm Hg (range: 2–25 mm Hg), with the Lin correlation coefficient of 0.74 (95% CI: 0.58–0.9). There was excellent interobserver agreement for dPAP from TR with the Lin correlation coefficient of 0.946 (95% CI: 0.803–0.986). Conclusion. Doppler estimation of dPAP from TR is a novel, reliable, noninvasive method and compares favorably with estimation from PR. Adequate TR signal for estimation of dPAP can be obtained more frequently in children than adequate PR signal, thereby increasing the proportion of patients in whom dPAP can be estimated noninvasively.     

Can echocardiographic evaluation of cardiopulmonary hemodynamics decrease right heart catheterizations in end-stage heart failure patients awaiting transplantation?

Candidacy for heart transplantation is influenced by the severity of pulmonary hypertension. In this study, invasive hemodynamics from right-sided cardiac catheterization were compared with values obtained by validated equations from Doppler 2-dimensional transthoracic echocardiography. This prospective study was conducted in 40 patients with end-stage heart failure evaluated for heart transplantation or ventricular assist device implantation. Transthoracic echocardiography and right-sided cardiac catheterization were performed within 4 hours. From continuous-wave Doppler of the tricuspid regurgitation jet, pulmonary artery systolic pressure was calculated as the peak gradient across the tricuspid valve plus right atrial pressure estimated from inferior vena cava filling. Mean pulmonary artery pressure was calculated as (0.61 × pulmonary artery systolic pressure) + 2. Pulmonary vascular resistance (PVR) was calculated as (tricuspid regurgitation velocity/right ventricular outflow tract time-velocity integral × 10) + 0.16. Pulmonary capillary wedge pressure was calculated as 1.91 + (1.24 × E/E'). Pearson's correlation and Bland-Altman analysis of mean differences between echocardiographic and right-sided cardiac catheterization measurements were statistically significant for all hemodynamic parameters (pulmonary artery systolic pressure: r = 0.82, p < 0.05, mean difference 3.1 mm Hg, 95% confidence interval [CI] -0.2 to 6.3; mean pulmonary artery pressure: r = 0.80, p < 0.05, mean difference 2.5 mm Hg, 95% CI 0.3 to 4.6; PVR: r = 0.52, p < 0.05, mean difference 0.8 Wood units, 95% CI 0.3 to 1.4; pulmonary capillary wedge pressure: r = 0.65, p < 0.05, mean difference 2.2 mm Hg, 95% CI 0.1 to 4.3). Compared with right-sided cardiac catheterization, PVR by Doppler echocardiography identified all patients with PVR > 4 Wood units (n = 4), 73% of patients with PVR <2 Wood units (n = 8), and 52% of patients with PVR from 2 to 4 Wood units (n = 10). In conclusion, echocardiographic estimation of cardiopulmonary hemodynamics is reliable in patients with end-stage cardiomyopathy. The noninvasive assessment of hemodynamics by echocardiography may be able to decrease the number of serial right-sided cardiac catheterizations in selected patients awaiting heart transplantation. However, in patients with borderline PVR, right-sided cardiac catheterization is indicated to assess eligibility for transplantation.     

Quantification of left-side intracardiac pressures and gradients using mitral and aortic regurgitant velocities by simultaneous left and right catheterization and continuous-wave doppler echocardiography

Noninvasive determination of left-side intracardiac pressures is of clinical importance in many cardiac diseases. To test the reliability and accuracy of left-side intracardiac pressure measurements by continuous-wave Doppler echocardiography, using left-side valvular regurgitations, 47 patients with mitral regurgitation, with or without associated aortic regurgitation, underwent simultaneous Doppler and left and right catheterization. Doppler-derived left atrial and ventricular end-diastolic pressures were respectively estimated by subtracting mitral regurgitant gradient from systolic blood pressure and by diastolic blood pressure minus aortic regurgitant gradient. There were high correlations of mitral (r = 0.961) and aortic regurgitant gradients (r = 0.896) and of left atrial (r = 0.945) and ventricular end-diastolic pressures (r=0.854) between noninvasive and invasive measurements. Also, agreement analyses showed that there was close agreement between the two technical measurements for each parameter. The present study concluded that continuous-wave Doppler echocardiography provides a reliable and accurate method for the noninvasive evaluation of left-side intracardiac pressures and gradients in patients with mitral and aortic regurgitations.     

Noninvasive estimation of right ventricular systolic pressure by Doppler ultrasound in patients with tricuspid regurgitation

We evaluated the accuracy of a noninvasive method for estimating right ventricular systolic pressures in patients with tricuspid regurgitation detected by Doppler ultrasound. Of 62 patients with clinical signs of elevated right-sided pressures, 54 (87%) had jets of tricuspid regurgitation clearly recorded by continuous-wave Doppler ultrasound. By use of the maximum velocity (V) of the regurgitant jet, the systolic pressure gradient (delta P) between right ventricle and right atrium was calculated by the modified Bernoulli equation (delta P = 4V2). Adding the transtricuspid gradient to the mean right atrial pressure (estimated clinically from the jugular veins) gave predictions of right ventricular systolic pressure that correlated well with catheterization values (r = .93, SEE = 8 mm Hg). The tricuspid gradient method provides an accurate and widely applicable method for noninvasive estimation of elevated right ventricular systolic pressures.     

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.     

Simultaneous measurement of left atrial pressure by Doppler echocardiography and catheterization.

Simultaneous, continuous wave Doppler echocardiography, left ventricular systolic and mean pulmonary capillary wedge pressure measurements were performed during cardiac catheterization in 54 patients with mitral regurgitation. Doppler-derived left atrial pressure, which was calculated by subtracting mitral regurgitant gradient from brachial artery systolic pressure, correlated well with mean pulmonary capillary wedge pressure by catheter (r = 0.933, SEE = 2.9 mmHg, P < 0.001); a comparison between non-invasive and invasive systolic gradients across the mitral valve yielded a high correlation (r = 0.91, SEE = 6.0 mmHg, P < 0.001); and there was also a high correlation between brachial artery and left ventricular systolic pressures (r = 0.93, SEE = 4.9 mmHg, P < 0.01). It is concluded that Doppler echocardiography provides a reliable and accurate method for complete non-invasive assessment of left atrial pressure in patients with mitral regurgitation.     

Two-dimensional and Doppler echocardiographic assessment of neonatal arterial repair for transposition of the great arteries

The arterial switch procedure has become an accepted reparative technique for transposition of the great arteries with or without ventricular septal defect. In this study the accuracy of prospective noninvasive imaging in detecting arterial tract obstruction and the prevalence and severity of arterial valvular regurgitation (as assessed by Doppler ultrasound) were evaluated in survivors of arterial repair. All 53 study patients underwent two-dimensional echocardiographic examination 2 days to 20 months (median 7 months) postoperatively; 43 patients also had pulsed and continuous wave Doppler studies. The accuracy of the noninvasive evaluation of arterial tract obstruction was determined by comparison of Doppler maximal instantaneous gradients with peak to peak gradients at nonsimultaneous catheterization in 26 patients. Twenty-one (81%) of the 26 patients underwent catheterization and successful pulsed and continuous wave Doppler examination of the right heart; 17 (81%) of these 21 had a maximal pressure gradient within 20 mm Hg of the peak to peak gradient obtained at catheterization. Echocardiographic identification of the stenotic site was correct in all eight of the patients in this group requiring reoperation. Twenty-three (88%) of the 26 patients who underwent catheterization had successful Doppler interrogation of the aortic tract; 22 (96%) of these 23 had a maximal instantaneous gradient within 20 mm Hg of the peak to peak catheterization gradient. Fourteen (32%) of 43 patients had mild or moderate pulmonary regurgitation by Doppler study. Three (7%) of the 43 had mild aortic regurgitation.     

The clinical significance of reversed flow in the main pulmonary artery detected by doppler color flow imaging

BACKGROUND: Using Doppler color flow imaging, abnormal flow patterns were reported to occur with pulmonary artery (PA) dilation. We have frequently observed red signals in the main PA, suggesting reversed flow (RF) in patients without overt pulmonary hypertension. The clinical implication of these signals has not been extensively studied. PATIENTS AND METHODS: We studied 191 of 412 patients referred for echocardiography (99 men and 92 women; mean +/- SD age, 62 +/- 13 years), in whom the main PA diameter had been adequately measured. If a red signal was observed by color flow imaging, a pulsed Doppler echocardiogram of the red signal was recorded simultaneously. The presence of the red signal was correlated with the PA diameter and the PA systolic pressure determined using the modified Bernoulli equation. In 54 patients who also underwent cardiac catheterization studies, the red signal was correlated with PA and pulmonary capillary wedge (PCW) pressures, and with pulmonary vascular resistance. RESULTS: Red signals adjacent to the medial PA border were detected in parallel with systolic blue signals in 127 patients (66%). Pulsed Doppler recordings revealed that they were caused by RF occurring immediately after the forward systolic signal and persisted in diastole. The PA diameter (28 +/- 4.8 mm) and the estimated PA systolic pressure (34 +/- 16 mm Hg) of patients with the RF signal were significantly greater (p < 0.001 and p < 0.05, respectively) than those of patients without the signal (22 +/- 2.5 mm and 28 +/- 6.0 mm Hg, respectively). Among patients who had hemodynamic studies, PA and PCW pressures were significantly higher (p < 0.05) in the 41 patients with the RF signal (22 +/- 12 mm Hg vs 15 +/- 2.6 mm Hg and 11 +/- 5.5 mm Hg vs 8 +/- 3.1 mm Hg, respectively). CONCLUSION:: RF signals in the main PA occur mostly as a result of PA dilation, which may be caused by primary pulmonary hypertension or chronic elevation of left atrial pressure in left-sided cardiac abnormalities.     

Echocardiography for Hemodynamic Assessment of Patients With Advanced Heart Failure and Potential Heart Transplant Recipients

Objectives. This study sought to assess the accuracy of Doppler echocardiographic techniques for the determination of right heart catheterization hemodynamic variables in patients with advanced heart failure and in potential heart transplant recipients.

Background. Doppler echocardiographic techniques permit the noninvasive acquisition of hemodynamic variables traditionally used for the assessment of patients with advanced heart failure and potential heart transplant candidates. However, the accuracy of these techniques has not been sufficiently well documented for clinical application in individual patients.

Methods. Echocardiographic data required for estimation of mean right atrial, pulmonary artery and mean left atrial pressures and cardiac output were obtained. Right heart catheterization was performed immediately after Doppler echocardiographic data were acquired, before any intervention that might have altered the subject’s hemodynamic status.

Results. A complete Doppler echocardiographic hemodynamic data set was acquired in 21 (84%) of 25 subjects. For all variables, invasive and noninvasive hemodynamic values were highly correlated (p < 0.001), with minimal bias and narrow 95% confidence limits. An algorithm constructed from the noninvasive hemodynamic variable values identified all patients with adverse pulmonary vascular hemodynamic variables (i.e., transpulmonary gradient ≥12 mm Hg, pulmonary vascular resistance ≥3 Wood units or pulmonary vascular resistance index ≥6 Wood units × m²). This algorithm identified 12 (71%) of 19 patients for whom right heart catheterization was unnecessary.

Conclusions. Doppler echocardiographic estimates of hemodynamic variables in patients with advanced heart failure are accurate and reproducible. This noninvasive methodology may assist with monitoring and optimization of medical therapy in patients with advanced heart failure and may obviate the need for routine right heart catheterization in potential heart transplant candidates.     

Continuous wave Doppler determination of right ventricular pressure: a simultaneous Doppler-catheterization study in 127 patients

Simultaneous continuous wave Doppler echocardiography and right-sided cardiac pressure measurements were performed during cardiac catheterization in 127 patients. Tricuspid regurgitation was detected by the Doppler method in 117 patients and was of adequate quality to analyze in 111 patients. Maximal systolic pressure gradient between the right ventricle and right atrium was 11 to 136 mm Hg (mean 53 +/- 29) and simultaneously measured Doppler gradient was 9 to 127 mm Hg (mean 49 +/- 26); for these two measurements, r = 0.96 and SEE = 7 mm Hg. Right ventricular systolic pressure was estimated by three methods from the Doppler gradient. These were 1) Doppler gradient + mean jugular venous pressure; 2) using a regression equation derived from the first 63 patients (Group 1); and 3) Doppler gradient + 10. These methods were tested on the remaining 48 patients with Doppler-analyzable tricuspid regurgitation (Group 2). The correlation between Doppler-estimated and catheter-measured right ventricular systolic pressure was similar using all three methods; however, the regression equation produced a significantly better estimate (p less than 0.05). Use of continuous wave Doppler blood flow velocity of tricuspid regurgitation permitted determination of the systolic pressure gradient across the tricuspid valve and the right ventricular systolic pressure. This noninvasive technique yielded information comparable with that obtained at catheterization. Approximately 80% of patients with increased and 57% with normal right ventricular pressure had analyzable Doppler tricuspid regurgitant velocities that could be used to accurately predict right ventricular systolic pressure.     

Effect of nitroglycerin on the pulmonary venous gradient in patients after mitral valve replacement

Because the equality of the pulmonary artery wedge pressure and left atrial pressure has been questioned in patients with mitral valve disease and pulmonary hypertension, this study examined how vasomotor activity in the pulmonary capacitance vessels might contribute to a discrepancy between these pressures. The difference between the pulmonary wedge and left atrial pressures (designated as the pulmonary venous gradient) was measured after nitroglycerin administration in nine patients who had pulmonary hypertension (mean pulmonary artery pressure 40 mm Hg) after mitral valve replacement. Five minutes after sublingual nitroglycerin, 0.4 mg, the mean pulmonary wedge pressure decreased from 19 +/- 2 to 13 +/- 2 mm Hg (p less than 0.005), exceeding the decrease in left atrial pressure (15 +/- 2 to 11 +/- 2 mm Hg; p less than 0.005). Pulmonary blood flow increased from 4.6 +/- 0.4 to 4.9 +/- 0.4 liters/min (p less than 0.005). The decrease in mean pulmonary venous gradient from 4.0 +/- 0.8 to 1.7 +/- 0.6 mm Hg (p less than 0.025) was attributed to nitrate-mediated pulmonary venodilation. The ratio of venous gradient to blood flow, an index of pulmonary venous tone, decreased after nitroglycerin from 0.9 +/- 0.2 to 0.4 +/- 0.1 (p less than 0.01). These data indicate that reversible pulmonary vasoconstriction contributes to elevation of the pulmonary wedge pressure above the left atrial pressure in patients with chronic mitral valve disease and pulmonary hypertension and that nitroglycerin may produce pulmonary venodilation decreasing the pulmonary venous gradient.     

Reliability of echocardiography for hemodynamic assessment of end-stage heart failure

The management of patients with end-stage heart failure is difficult and may require the monitoring of intracardiac pressures. The aim of this prospective study was to assess the reliability of echocardiography in patients with end-stage HF. Twenty consecutive patients presenting with severe left ventricular dysfunction in end-stage heart failure were prospectively studied. All patients underwent right-sided cardiac catheterization and transthoracic echocardiography. Right atrial pressure, estimated using a new echocardiographic parameter, was significantly improved. There was good agreement between systemic and pulmonary vascular resistance, determined by catheterization and echocardiography. All patients with echocardiographic pulmonary vascular resistance<6 Wood units also had invasive pulmonary vascular resistance<6 Wood units. Only echocardiographic mean right atrial pressure was related to the use of saline infusion or bolus infusion of furosemide. All patients requiring intravenous furosemide had pulmonary capillary wedge pressures persistently>or=15 mm Hg despite adequate medication. In conclusion, this study indicates that echocardiography may be a reliable tool for the management of patients with end-stage heart failure.     

Diastolic mitral regurgitation with atrioventricular conduction abnormalities: relation of mitral flow velocity to transmitral pressure gradients in conscious dogs

Diastolic mitral regurgitation is a common finding that can be detected with use of Doppler echocardiographic techniques in patients with atrioventricular (AV) conduction abnormalities. With use of simultaneous hemodynamic and Doppler techniques, mitral flow velocity, mitral valve motion and transmitral pressure gradient were studied during 50 cardiac cycles each of spontaneous or atrial paced first- and second-degree AV block in five lightly sedated dogs. Diastolic mitral regurgitation was detected during atrial relaxation on all beats in which ventricular contraction was delayed greater than 190 ms. In all dogs the diastolic regurgitation was associated with a reverse transmitral pressure gradient (3.7 +/- 1.1 mm Hg in first-degree AV block and 3.2 +/- 1.5 mm Hg in second-degree AV block) that occurred primarily as the result of a decrease in atrial pressure with atrial relaxation. These reverse pressure gradients were as large as the maximal forward transmitral gradients in early diastole (2.9 +/- 0.9 mm Hg in first-degree AV block and 3.1 +/- 0.7 mm Hg in second-degree AV block) and larger than the maximal forward pressure gradients at atrial contraction (1.7 +/- 0.5 and 1.4 +/- 0.6 mm Hg, respectively, p less than 0.05). The maximal reverse pressure gradient during atrial relaxation was also as large as the reverse pressure gradient in mid-diastole (2.7 +/- 0.9 and 2.8 +/- 1.0 mm Hg, respectively), associated with deceleration of early diastolic mitral flow. Peak diastolic mitral regurgitation velocity coincided with the maximal reverse transmitral gradient and was usually larger than anterograde mitral flow velocity.(ABSTRACT TRUNCATED AT 250 WORDS)