Estimation Of Left Atrial Pressure Research Articles

Novel algorithm for non-invasive estimation of left atrial pressure in patients with atrial fibrillation.

Determining elevated left atrial (LA) pressure is crucial in patients with atrial fibrillation (AF), yet non-invasive estimation using echocardiography remains unclear. This study aimed to identify useful echocardiographic indices for identifying elevated LA pressure in patients with AF. Patients with paroxysmal or persistent AF referred for catheter ablation at two tertiary hospitals were prospectively enrolled. Mean LA pressure was measured immediately after transseptal puncture. Elevated mean LA pressure was defined as ≥15 mmHg. Transthoracic echocardiography was performed to acquire the guideline-recommended parameters. A total of 176 patients were included, and 63 (36%) patients had a mean LA pressure ≥15 mmHg. Patients with elevated LA pressure had more frequent hypertension, larger LA, higher septal E/e', and worse LA strain than the remaining patients. The correlations between mean LA pressure and each echocardiographic parameter were weak. Septal E/e' ratio showed the best correlation with mean LA pressure (r = 0.351, P < 0.001), and septal E/e' ratio ≥11 was the best parameter (area under the curve = 0.7, sensitivity = 65%, specificity = 73%, accuracy = 70%) to identify elevated mean LA pressure. A hierarchical algorithm consisting of septal E/e' ratio, LA reservoir strain, and LA volume index improved identification of patients with elevated mean LA pressure (sensitivity = 61%, specificity = 91%, accuracy = 80%). In patients with AF, the septal E/e' ratio was the best single parameter for identifying elevated mean LA pressure. A hierarchical algorithm combining the septal E/e' ratio, LA reservoir strain, and LA volume index helps identify elevated LA pressure in patients with AF.

Validation of E/e′ Using the Index-Beat Method as an Estimate of Left Atrial Pressure in Patients with Atrial Fibrillation

Introduction: Echocardiographic assessment of diastolic function during atrial fibrillation (AF) remains challenging due to the irregular cardiac cycle length. We sought to assess whether the index-beat method, the beat following two preceding cardiac cycles of equal duration, could provide a more reliable measurement of E/e′ (mitral E wave/diastolic tissue Doppler velocity) than the conventional averaging of consecutive beats and hence facilitate the noninvasive estimation of elevated left atrial pressure (LAP) in patients with AF. Methods: We prospectively studied 35 patients with persistent AF who had preserved left ventricular ejection fraction and underwent radiofrequency ablation. LAP was measured in conjunction with transseptal puncture during catheter ablation. Echocardiography was performed 24 h before ablation and E/e′ was determined using the recommended averaging of 10 beats and the index-beat method, with the observers blinded to the clinical details and LAP measurements. Results: Correlation analysis showed a strong positive correlation between two methods in terms of both septal E/e′ (r = 0.841, p < 0.001) and lateral E/e′ (r = 0.930, p < 0.001). Bland-Altman analysis also showed a good agreement between the two measurement methods in terms of E/e′. E/e′ determined using both conventional averaging and the index-beat method was significantly correlated with LAP (p < 0.05). After Fisher Z transformation, we found that the index-beat septal E/e′ had a better correlation with LAP than did the conventional averaging E/e′ (r = 0.736 vs. r = 0.392, Zr = −2.110, p = 0.035). Furthermore, the index-beat method took significantly less time to measure E/e′ (mean 33.6 s; 95% confidence intervals [CIs]: 32.1 s–36.2 s) than did conventional averaging method (mean 96.2 s; 95% CI: 90.2 s–102.3 s; p < 0.001). Receiver operating characteristic curve analysis revealed that the optimal cut-off for predicting mean LAP >12 mm Hg was 11 (sensitivity 100%; specificity 77.3%) for index-beat septal E/e′ and 16 (sensitivity 61.5%; specificity 95.5%) for index-beat lateral E/e′. Conclusions: Good correlations were found between E/e′ and LAP in patients with AF, particularly with the index-beat method. Moreover, the index-beat method can easily measure E/e′ at an accuracy similar to that for the conventional averaging of consecutive beats, which can therefore be applied to assess the diastolic dysfunction and potentially improve the diagnosis of heart failure in patients with AF.

Potential role of left atrial strain in estimation of left atrial pressure in patients with chronic heart failure.

In a large proportion of heart failure with reduced ejection fraction (HFrEF) patients, echocardiographic estimation of left atrial pressure (LAP) is not possible when the ratio of the peak early left ventricular filling velocity over the late filling velocity (E/A ratio) is not available, which may occur due to several potential causes. Left atrial reservoir strain (LASr) is correlated with LV filling pressures and may serve as an alternative parameter in these patients. The aim of this study was to determine whether LASr can be used to estimate LAP in HFrEF patients in whom E/A ratio is not available. Echocardiograms of chronic HFrEF patients were analysed and LASr was assessed with speckle tracking echocardiography. LAP was estimated using the current ASE/EACVI algorithm. Patients were divided into those in whom LAP could be estimated using this algorithm (LAPe) and into those in whom this was not possible because E/A ratio was not available (LAPne). We assessed the prognostic value of LASr on the primary endpoint (PEP), which comprised the composite of hospitalization for the management of acute or worsened HF, left ventricular assist device implantation, cardiac transplantation, and cardiovascular death, whichever occurred first in time. We studied 153 patients with a mean age of 58years of whom 76% men and 82% who were in NYHA class I-II. A total of 86 were in the LAPe group and 67 in the LAPne group. LASr was significantly lower in the LAPne group as compared with the LAPe group (15.8% vs. 23.8%, P<0.001). PEP-free survival at a median follow-up of 2.5years was 78% in LAPe versus 51% in LAPne patients. An increase in LASr was significantly associated with a reduced risk of the PEP in LAPne patients (adjusted hazard ratio: 0.91 per %, 95% confidence interval 0.84-0.98). An abnormal LASr (<18%) was associated with a five-fold increase in reaching the PEP. In HFrEF patients in whom echocardiographic estimation of LAP is not possible due to due to unavailability of E/A ratio, assessing LASr potentially carries added clinical and prognostic value.

Echocardiographic vs Invasive Estimation of Left Atrial Pressure – Ongoing Search for the Holy Grail

Elevated mean left atrial pressure (mLAP) is the key pathophysiological consequence of heart failure and the underlying cause of dyspnoea across the spectrum of left-sided valvular and pericardial diseases. Echocardiographic estimation of mLAP can be calculated by the equation mLAPECHO =1.24x(E/E’)+1.9. This formula was developed by correlation with mean pulmonary capillary wedge pressure at right heart catheterisation. Evidence of validation against direct mLAP measurements is lacking.

Proteomics to improve phenotyping in obese patients with heart failure with preserved ejection fraction.

Recent evidence points towards a distinct obese phenotype among patients with heart failure with preserved ejection fraction (HFpEF). We aimed to identify differentially expressed circulating biomarkers in obese HFpEF patients and link them to disease severity and outcomes. From the LIFE-Heart study, 999 patients with HFpEF and 999 patients without heart failure (no-HF) were selected and 92 circulating serum biomarkers were measured using a proximity extension assay. Elevation of identified biomarkers was validated in 220 patients from the Aldo-DHF trial with diagnosed HFpEF. HFpEF patients were older and had more comorbidities including coronary artery disease and type 2 diabetes as compared to no-HF patients (P < 0.05 for all). After adjusting for covariates, adrenomedullin (ADM), galectin-9 (Gal-9), thrombospondin-2 (THBS-2), CD4, and tumour necrosis factor-related apoptosis-inducing ligand receptor 2 (TRAIL-R2) were significantly higher in obese HFpEF patients [body mass index (BMI) ≥30 kg/m2 , n=464] as compared to lean HFpEF (BMI <30 kg/m2 , n=535) and obese no-HF patients (BMI ≥30 kg/m2 , n=387) (P < 0.001 for both); these findings were verified in the Aldo-DHF validation cohort (P < 0.001). Except for CD4 these proteins were associated with increased estimates of left atrial pressure in a linear fashion. Importantly, ADM and CD4 were associated with increased mortality in obese HFpEF patients after adjusting for covariates. Obese HFpEF patients exhibit higher circulating biomarkers of volume expansion (ADM), myocardial fibrosis (THBS-2) and systemic inflammation (Gal-9, CD4) compared to obese non-HFpEF or lean HFpEF patients. These findings support the clinical definition of a distinct obese HFpEF phenotype and might merit further investigation.

NON-INVASIVE ASSESSMENT OF LEFT ATRIAL PRESSURE USING ARTERIAL TONOMETRY AND ITS CORRELATION WITH TISSUE DOPPLER ECHOCARDIOGRAPHY AND PULMONARY CAPILLARY WEDGE PRESSURE

Doppler echocardiography (TTE) has been validated for qualitative estimation of left atrial pressure (LAP). However, its accuracy in quantitative assessment of LAP is not known. Arterial tonometry (AT) has been validated for estimation of aortic pressure (AP). We sought to assess accuracy of E/e’

59-Year-Old Woman With Fatigue, Dyspnea, and Lower Extremity Edema

59-Year-Old Woman With Fatigue, Dyspnea, and Lower Extremity Edema

Noninvasive estimation of left atrial pressure with transesophageal echocardiography.

Background:The pulmonary artery catheter (PAC) has historically been used to measure cardiac filling pressures of which pulmonary capillary wedge pressure (PCWP) has been used as a surrogate of left atrial pressure (LAP) and left ventricular end-diastolic pressure. Increasingly, the use of the PAC has been questioned in the perioperative period with multiple large studies unable to clearly demonstrate benefit in any group of patients, resulting in a declining use in the perioperative period. Alternative methods for the noninvasive estimation of left-sided filling pressures are required. Echocardiography has been used to provide noninvasive estimation of PCWP and LAP, based on evaluating mitral inflow velocity with the E and A waves and looking at movement of the mitral annulus with tissue Doppler (e’).Aim:The aim of our study was to assess the relationship between PCWP and E/e’ in cardiac surgical patients with transesophageal echocardiography (TOE).Design:A prospective observational study.Setting:Cardiac surgical patients in a single quaternary referral university teaching hospital.Methods:The ratio of mitral inflow velocity (E wave) to mitral annular tissue velocity (e’) (the E/e’ ratio) and PCWP of 91 patients undergoing general anesthesia and cardiac surgery were simultaneously recorded, with the use of TOE and a PAC.Results:The correlation between E/e’ and PCWP was modest with a Spearman rank correlation coefficient of 0.29 (P = 0.005). The area under the receiver operating characteristic curve for using E/e’ to predict elevated PCWP (≥18 mmHg) was 0.6825 (95% confidence interval: 0.57–0.80), indicating some predictive utility. The optimum threshold value of E/e’ was 10 which had 71% sensitivity and 60% specificity to predict a PCWP ≥18 mmHg.Conclusions:Noninvasive measurements of E/e’ in general cardiac surgical patients have only a modest correlation and does not reliably estimate PCWP.

Echocardiographic Estimation of Left Atrial Pressure in Beagle Dogs with Experimentally-Induced Mitral Valve Regurgitation

Non-invasive and immediate estimation of left atrial pressure (LAP) is very useful for the management of mitral regurgitation (MR), and many reports have assessed echocardiographic estimations of LAP to date. However, it has been unclear of which examination and evaluate article possess the best accuracy for the MR severity. The present research aims to establish the echocardiographic estimation equation of LAP that is well applicable for clinical MR dogs. After the chordae tendineae rupture was experimentally induced via left atriotomy in six healthy beagle dogs (three males and three females, two years old, weighing between 9.8 to 12.8 kg), a radio telemetry transmitter catheter was inserted, which allows the continuous recordings of LAP without the use of sedation. Approximately 5 weeks after the surgery, echocardiographic examination, indirect blood pressure measurement, measurement of plasma atrial natriuretic peptide (ANP) and LAP measurement by way of the radio telemetry system was performed simultaneously. Subsequently, simple linear regression equations between LAP and each variable were obtained, and the equations were evaluated whether to be applicable for clinical MR dogs. As a result, the ratio of early diastolic mitral flow to early diastolic lateral mitral annulus velocity (E/Ea) had the strongest correlation as maximum LAP=7.03*(E/Ea)-54.86 (r=0.74), and as mean LAP=4.94*(E/Ea)-40.37 (r=0.70) among the all variables. Therefore, these two equations associated with E/Ea should bring more precise and instant estimations of maximum and mean LAP in clinical MR dogs.

1113 Noninvasive estimation of left atrial pressure in patients with mitral regurgitation by Doppler echocardiography and brachial sphygmomanometry: correlation with findings on cardiac catheterization

1113 Noninvasive estimation of left atrial pressure in patients with mitral regurgitation by Doppler echocardiography and brachial sphygmomanometry: correlation with findings on cardiac catheterization

Tissue Doppler echocardiographic and color M-mode estimation of left atrial pressure in infants*

Using recorded flow and tissue Doppler, we evaluated the relation of peak velocity of early transmitral Doppler filling (E)/early diastolic velocity of the lateral mitral annulus (Ea) ratio and of E/flow propagation velocity (Vp) ratio to mean left atrial pressure in infants after surgery for congenital heart disease. Experimental design. Pediatric intensive care unit. Thirty-seven infants aged 4 (3-8) months. Patients underwent postoperative invasive hemodynamic monitoring with simultaneously obtained Doppler measurements. Values are expressed as median (25th-75th percentiles). Heart rate was 145 (135-157) beats/min. Left atrial pressure was 10 (8-12) mm Hg with E/Ea 16 (12-19) and E/Vp 1.9 (1.3-2.4). E/Ea and E/Vp ratios were higher in patients with left atrial pressure >10 mm Hg (n = 18), than in patients with left atrial pressure < or =10 mm Hg (n = 19) (E/Ea, 16 [15-25] vs. 12 [9-17], p = .01; E/Vp, 2.3 [1.9-2.8] vs. 1.4 [1-1.9]. respectively, p = .001). At a cutoff point of 15, E/Ea sensitivity for left atrial pressure >10 mm Hg was 17 of 18 (94%) with specificity 13 of 18 (72%). At a cutoff point of 2, E/Vp sensitivity for left atrial pressure >10 mm Hg was 15 of 18 (83%) with specificity 16 of 18 (89%). Areas under the receiver operating characteristic curves were 0.76 (E/Ea) and 0.83 (E/Vp). Doppler ratios might be considered as promising noninvasive tools for left atrial pressure evaluation in infants after cardiac surgery.

Estimation of left atrial pressure using doppler tissue imaging in a canine model of valvular insufficiency

Estimation of left atrial pressure using doppler tissue imaging in a canine model of valvular insufficiency

Relation of pulmonary arterial diastolic and mean pulmonary arterial wedge pressures in patients with and without pulmonary hypertension

Management of the critically ill or postoperative patient in the intensive care unit may be facilitated by the measurement of right-sided and certain left-sided intracardiac filling pressures with a balloon-tipped, flow-directed catheter. Although previous studies have shown that properly obtained and oximetrically confirmed pulmonary arterial wedge pressure provides an accurate estimate of left atrial pressure, 1 Werko L. Varnauskas E. Eliasch H. Lagerlof H. Senning A. Thommasson B. Further evidence that the pulmonary capillary venous pressure pulse in man reflects cyclic pressure changes in the left atrium. Circ Res. 1953; 1: 337-344 Crossref PubMed Scopus (28) Google Scholar , 2 Connolly D.C. Kirklin J.W. Wood E.H. The relationship between pulmonary artery wedge pressure and left atrial pressure in man. Circ Res. 1953; 2: 434-440 Crossref Scopus (75) Google Scholar , 3 Lange R.A. Moore D.M. Cigarroa R.G. Hillis L.D. Use of pulmonary capillary wedge pressure to assess severity of mitral stenosis Is true left atrial pressure needed in this condition?. J Am Coll Cardiol. 1953; 13: 825-829 Abstract Full Text PDF Scopus (55) Google Scholar the procurement of an oximetrically confirmed wedge pressure may be difficult or impossible in some subjects. As a result, some investigators 4 Lipp-Ziff E.L. Kawanishi D.T. A technique for improving the accuracy of pulmonary artery diastolic pressure as an estimate of left ventricular end-diastolic pressure. Heart Lung. 1953; 20: 107-115 Google Scholar have suggested that pulmonary arterial diastolic pressure can be used as a surrogate for mean pulmonary arterial wedge pressure and, in turn, mean left atrial pressure. In 28 patients with varied pulmonary vascular resistances, Jenkins et al 5 Jenkins B.S. Bradley R.D. Branthwaite M.A. Evaluation of pulmonary arterial end-diastolic pressure as an indirect estimate of left atrial mean pressure. Circulation. 1953; 152: 75-78 Google Scholar demonstrated an excellent correlation between pulmonary arterial diastolic and mean left atrial pressures. Despite these reports, no previously published study has assessed the relation of pulmonary arterial diastolic to mean pulmonary arterial wedge pressures in a large number of patients in whom the catheter’s wedge position was confirmed oximetrically. Accordingly, this study was performed to assess this relation and to determine if it is influenced by pulmonary hypertension.

Clinical Assessment of Left Ventricular Relaxation

Ventricular relaxation is altered in a number of cardiac disorders affecting domestic animals. Clinical determination of the ventricular relaxation rate can provide useful information regarding disease severity and response to therapy. We believe that the current gold standard for assessing left ventricular relaxation requires measurement of ventricular luminal pressure at end-expiration using a high-fidelity catheter. Ventricular pressure should be digitized at > or = 200 Hz for the period of pressure fall between the minimum rate of change of ventricular pressure and 10 mm Hg above left ventricular end-diastolic pressure of the preceding beat. The rate of relaxation then should be determined from the digitized data by Marquardt nonlinear least squares parameter estimation using an exponential decay model with nonzero asymptote. The major disadvantage in using an invasive method for evaluating left ventricular relaxation is that it requires general anesthesia in animals that frequently are categorized as high-risk anesthetic patients. Noninvasive estimates of ventricular relaxation using echocardiographic parameters such as isovolumic relaxation time, peak early filling rate, and time from end-systole to peak filling rate provide a crude and nonspecific assessment of ventricular relaxation that can be obtained from conscious animals. Determinations of these echocardiographic indices are of limited usefulness in assessing changes in ventricular relaxation associated with disease progression or therapeutic intervention, unless concurrent estimates of left atrial pressure, mitral valve characteristics, and left ventricular compliance are available.

Clinical Assessment of Left Ventricular Relaxation

Ventricular relaxation is altered in a number of cardiac disorders affecting domestic animals. Clinical determination of the ventricular relaxation rate can provide useful information regarding disease severity and response to therapy. We believe that the current gold standard for assessing left ventricular relaxation requires measurement of ventricular luminal pressure at end-expiration using a high-fidelity catheter. Ventricular pressure should be digitized at ≥200 Hz for the period of pressure fall between the minimum rate of change of ventricular pressure and 10 mm Hg above left ventricular end-diastolic pressure of the preceding beat. The rate of relaxation then should be determined from the digitized data by Marquardt nonlinear least squares parameter estimation using an exponential decay model with nonzero asymptote. The major disadvantage in using an invasive method for evaluating left ventricular relaxation is that it requires general anesthesia in animals that frequently are categorized as high-risk anesthetic patients. Noninvasive estimates of ventricular relaxation using echocardiographic parameters such as isovolumic relaxation time, peak early filling rate, and time from end-systole to peak filling rate provide a crude and nonspecific assessment of ventricular relaxation that can be obtained from conscious animals. Determinations of these echocardiographic indices are of limited usefulness in assessing changes in ventricular relaxation associated with disease progression or therapeutic intervention, unless concurrent estimates of left atrial pressure, mitral valve characteristics, and left ventricular compliance are available.

Comparison of Central Venous Pressure, Diastolic Pulmonary Artery Pressure and Pulmonary Capillary Wedge Pressure and Pulmonary Capillary Wedge Pressure as Estimates of Left Atrial Pressure

Background: To evaluate the left heart function, left atrial pressure(LAP) has been monitored directly via LA catheter and indirectly via Swan-Ganz catheter. But indirect pressure monitor cannot often reflect the LAP precisely. We compared the LAP via LA catheter with central venous pressure(CVP), diastolic pulmonary artery pressure(DPAP) and pulmonary capillary wedge pressure(PCWP) by Swan-Ganz catheter. Methods: Eleven cardiac-surgical patients whose LAP measurements were needed for clinical management were the subjects of this study. The CVP, DPAP and PCWP by Swan-Ganz catheter, and LAP were measured just after cardiopulmonary bypass, just after sternal closure, after 6 hours and 18 hours from the end of operation. And we divided them into two groups which consisted below 35 mmHg(group I) and over 35 mmHg(group II) of systolic pulmonary artery pressure(SPAP), and compared two groups. Results: In group I, the LAP, CVP, DPAP and PCWP was 11.7±3.9 mmHg, 10.5±3.9 mmHg, 12.5±5.1 mmHg and 12.5±4.4 mmHg respectively, and correlation coefficiency of LAP with CVP, DPAP and PCWP was 0.7478, 0.7128 and 0.9002 respectively(p<0.05). In the group II, the LAP, CVP, DPAP and PCWP was 16.5±3.2 mmHg, 12.8±2.9 mmHg, 23.4±3.8 mmHg and 20.8±4.7 mmHg respectively and there was no correlation between LAP, CVP, DPAP and PCWP. Conclusion: The Swan-Ganz catheterization for the estimation of LAP is useful in the patients without pulmonary hypertension, but in the patient with pulmonary hypertension, CVP, DPAP and PCWP do not reflect the LAP.(Korean J Anesthesiol 1996; 30: 172~177)

785-5 Color Doppler M-Mode Velocity Propagation: An Index of Early Left Ventricular Filling That Combined with Pulsed Doppler Peak E Velocity may Predict Left Atrial Pressure

The propagation velocity of transmitral flow (MVP). as defined by color Doppler M-mode, has recently been proposed as an index of ventricular relaxation. Left atrial pressure, relaxation and left ventricular contractility are the main determinants of peak E wave To assess the possibility of estimating left atrial pressure using pulsed Doppler peak E wave velocity and color Doppler IMVP). we studied 27 patients in the coronary care unit. Methods Peak early filling velocity IE) was measured using pulsed Doppler, while the slope of the color Doppler M-mode (S)was used to define mitral flow velocity propagation. All patients had a pulmonary artery catheter and pulmonary capillary wedge pressure was measured. The dimensionless ratio E/S (range 092–3.74) was significantly related to left atrial pressure (r = 0.74, P &lt; 0.001). and provided a good predictor for left atrial pressure (LAP = 4.4 + 5.3E/S, SEE = 3.7 mmHg). S (37.2 ± 12.2 m/sec) was significantly lower than E(73.5 ± 26.3). p &lt; 0.001, with no correlation between these velocities (r = 0.24). E was weakly correlated with LAP (r = 0.53, P = 0.005), while S showed a negative correlation (r = -0.325, P = NS). 1) The ratio of component velocity (E) over propagation velocity (S) of early ventricular filling wave can provide an good estimate of left atrial pressure. 2) Transmitral flow velocity propagation is independent of the component velocities of the E wave, 3) S is not related to LAP.

Transesophageal continuous wave Doppler estimation of left atrial pressure with interatrial shunting

Transesophageal continuous wave Doppler estimation of left atrial pressure with interatrial shunting

Left ventricular energy in mitral regurgitation: a preliminary report.

Energy exchange based on Newtonian principles is the most appropriate way to express the function of any pump--including the heart. Using information obtained at cardiac catheterisation, we have measured the total work energy (ET) of the left ventricle (LV) (mean 1.63 F) in patients with severe mitral regurgitation (mean regurgitant fraction 0.66). ET was approximately 84% above normal. Of the regurgitant energy (RE) (mean 0.95 F), on average , 3/4 (73.6%) was kinetic (KE) and 1/4 (23.4%) potential (PE). Both components represent wasted LV energy: the kinetic energy associated with turbulence lost as heat, the potential energy responsible for a rise in Left Atrial (LA) pressure. The amount of PE as a percentage of total regurgitant energy (RE) varied considerably from one patient to another (10.5% to 54.4%). Hence, colour flow mapping which detects only KE of turbulent jet flow must underestimate LV energy loss and, because of patient to patient variation, cannot consistently reflect severity of regurgitation. Measurements of PE correlate well with wedge P-wave height. Corresponding non-invasive estimates were made using sphygmodynamometer-calibrated indirect carotid pulse tracings and echocardiographic measurements. These were not significantly different from the invasive measurements. Unfortunately, the calculation of PE is indirect and involves subtraction, so that measurements for individual patients were not accurate enough for clinical use. Part of the non-invasive calculation involved an estimate of left atrial pressure based on the blood pressure measurement and Doppler velocity of regurgitation; this should be a useful measurement in itself.(ABSTRACT TRUNCATED AT 250 WORDS)

Echocardiographic estimate of left atrial pressure in children.

Echocardiographic estimates of left atrial pressure (LAP) using the Q-C/A2-E ratio were obtained from 40 patients and compared with directly recorded mean LAP and/or pulmonary wedge pressure (PWP). The best correlation was obtained between LAP and the Q-C/A2-E (gamma = 0.95, P < 0.01); a good one between PWP and the Q-C/A2-E in normal and moderate pulmonary hypertension (gamma = 0.82, P < 0.01), but a poor one in severe pulmonary hypertension (gamma = 0.61, P > 0.05). Consequently, echocardiography provides a useful noninvasive method for the estimation of the LAP and PWP, particularly appropriate for children Intensive Care Unit.