Estimation Of Pulmonary Capillary Wedge Pressure Research Articles

Noninvasive Prediction of Pulmonary Capillary Wedge Pressure in Patients With Normal Left Ventricular Ejection Fraction: Comparison of Cardiac Magnetic Resonance With Comprehensive Echocardiography

Cardiac magnetic resonance (CMR) was recently reported to predict mean pulmonary capillary wedge pressure (PCWP). However, there is a paucity of data on its accuracy for estimation of PCWP in patients with normal left ventricular (LV) ejection fraction (EF). We sought to examine its accuracy against the invasive gold standard and to compare it with the accuracy of comprehensive echocardiography. Stable patients with EF of ≥50% who underwent right heart catheterization, CMR, and echocardiographic imaging within 1week were included. Pulmonary capillary wedge pressure was estimated by CMR using a previously validated equation where PCWP is estimated based on the left atrial maximum volume and LV mass. Echocardiographic estimation of PCWP was based on 2016 American Society of Echocardiography/European Association of Cardiovascular Imaging guidelines, taking into account the presence of myocardial disease. The mean age of the 79 patients was 55±15years, and 58.2% were female. There were 33 patients with PCWP >15mm Hg by right heart catheterization. Cardiac magnetic resonance prediction of PCWP had an area under the curve (AUC)=0.72. In comparison, echocardiographic prediction of PCWP showed a higher accuracy (AUC=0.87 vs AUC=0.72; P=.008). In patients with normal LV EF, CMR estimation of mean PCWP based on LV mass and left atrial volume has modest accuracy for detecting patients with mean PCWP >15mm Hg. Comprehensive echocardiography predicts elevated PCWP with higher accuracy in comparison with CMR.

Abstract 14855: Noninvasive Prediction of Pulmonary Capillary Wedge Pressure in Patients With Normal LV EF: Comparison of CMR With Echocardiography

Background: Cardiac magnetic resonance (CMR) was recently reported to predict mean pulmonary capillary wedge pressure (PCWP) with the best accuracy in mid-rage or reduced left ventricular (LV) ejection fraction (EF). . There is a paucity of data on the accuracy of CMR estimation of PCWP in patients with normal left ventricular (LV) ejection fraction (EF) or on how CMR compares with echocardiography in these patients. Methods: Stable patients with EF of ≥50%, who underwent right heart catheterization (RHC), CMR, and echocardiographic imaging within one week were included. PCWP was estimated by CMR using a previously validated equation where PCWP is estimated based on the left atrial maximum volume (LAV) and left ventricular mass (LVM) as PCWP=6.1352+ (0.07204*LAV) + (0.02256*LVM). Echocardiographic estimation of PCWP was based on 2016 ASE/EACVI guidelines taking into account the presence of myocardial disease and pulmonary vein atrial velocity. Results: Mean age was (54.6 ± 15.2), 58.2% females. There were 33 patients with PCWP > 15 mmHg by RHC and 46 with a normal PCWP by right heart catheterization. The table shows sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for the two imaging modalities. CMR prediction of PCWP had an AUC=0.72. In comparison, echocardiographic prediction of PCWP had significantly higher accuracy (AUC=0.87 vs. AUC=0.72; P- value=0.008). Conclusion: In patients with normal LV EF, CMR estimation of mean PCWP has an acceptable accuracy for detecting patients with mean PCWP>15 mmHg. Echocardiography predicts elevated PCWP with a significantly higher sensitivity, specificity, and overall accuracy in comparison with CMR.

The Left Atrial Area Derived Cardiovascular Magnetic Resonance Left Ventricular Filling Pressure Equation Shows Superiority over Integrated Echocardiography.

Background and objectives: Evaluating left ventricular filling pressure (LVFP) plays a crucial role in diagnosing and managing heart failure (HF). While traditional assessment methods involve multi-parametric transthoracic echocardiography (TTE) or right heart catheterisation (RHC), cardiovascular magnetic resonance (CMR) has emerged as a valuable diagnostic tool in HF. This study aimed to assess a simple CMR-derived model to estimate pulmonary capillary wedge pressure (PCWP) in a cohort of patients with suspected or proven heart failure and to investigate its performance in risk-stratifying patients. Materials and methods: A total of 835 patients with breathlessness were evaluated using RHC and CMR and split into derivation (85%) and validation cohorts (15%). Uni-variate and multi-variate linear regression analyses were used to derive a model for PCWP estimation using CMR. The model's performance was evaluated by comparing CMR-derived PCWP with PCWP obtained from RHC. Results: A CMR-derived PCWP incorporating left ventricular mass and the left atrial area (LAA) demonstrated good diagnostic accuracy. The model correctly reclassified 66% of participants whose TTE was 'indeterminate' or 'incorrect' in identifying raised filling pressures. On survival analysis, the CMR-derived PCWP model was predictive for mortality (HR 1.15, 95% CI 1.04-1.28, p = 0.005), which was not the case for PCWP obtained using RHC or TTE. Conclusions: The simplified CMR-derived PCWP model provides an accurate and practical tool for estimating PCWP in patients with suspected or proven heart failure. Its predictive value for mortality suggests the ability to play a valuable adjunctive role in echocardiography, especially in cases with unclear echocardiographic assessment.

Non-invasive evaluation of pulmonary capillary wedge pressure using the left atrial expansion index in mitral valve stenosis, prosthesis and repair.

Pulmonary capillary wedge pressure (PCWP) non-invasive evaluation is limited in patients with mitral valve (MV) stenosis, prosthesis, and surgical repair. This study aimed to assess the left atrial expansion index (LAEI) measured through transthoracic echocardiography (TTE) as a novel parameter for estimating PCWP in these challenging cardiac conditions. We performed a retrospective, cross-sectional study, including chronic cardiac patients receiving within 24h a clinically indicated right heart catheterization (RHC) and transthoracic echocardiographic (TTE) exam. PCWP measured during RHC was used as the reference. TTE measurements were performed offline, blinded to RHC results. LAEI was calculated as LAEI = [(LAmaxVolume-LAminVolume)/LAminVolume] × 100. We included 167 patients (age = 73 ± 11.5years; PCWP = 18 ± 7.7mmHg) with rheumatic mitral valve (MV) stenosis (16.2%), degenerative MV stenosis (51.2%), MV prosthesis (18.0%), and MV surgical repair (13.8%). LAEI correlated logarithmically with PCWP, and the log-transformed LAEI (lnLAEI) showed a good linear association with PCWP (r = -0.616; p < 0.001). lnLAEI was an independent PCWP determinant, providing added predictive value over conventional clinical (age, atrial fibrillation, heart rate, MV subgroups) and echocardiographic variables (LVEF, MV effective orifice area, MV mean gradient, net atrioventricular compliance, and pulmonary arterial systolic pressure). lnLAEI identified PCWP > 12mmHg with AUC = 0.870, p < 0.001; and PCWP > 15mmHg with AUC = 0.797, p < 0.001, with an optimal cut-off of lnLAEI < 3.69. The derived equation PCWP = 36.8-5.5xlnLAEI estimated the invasively measured PCWP ± 6.1mmHg. In this cohort of patients with MV stenosis, prosthesis, and surgical repair, lnLAEI resulted in a helpful echocardiographic parameter for PCWP estimation.

Left Atrial Expansion Index for Noninvasive Estimation of Pulmonary Capillary Wedge Pressure: A Cardiac Catheterization Validation Study

Pulmonary capillary wedge pressure (PCWP) plays a pivotal role in cardiac disease diagnosis and management. Right heart catheterization (RHC) invasively provides accurate PCWP measurement, but it is impractical for widespread use in all patients. The left atrial expansion index (LAEI), measured on transthoracic echocardiography, describes the relative left atrial volume increase during the left atrial reservoir phase. The aim of this study was to validate LAEI as a noninvasive parameter for PCWP estimation. A total of 649 chronic cardiac patients (mean age, 66±14years; mean PCWP, 14±7.6mm Hg; mean left ventricular ejection fraction, 50±15%) who underwent both clinically indicated RHC and transthoracic echocardiography within 24hours were retrospectively enrolled. Patients were randomly divided into derivation (n=509) and validation (n=140) cohorts. PCWP was measured during RHC and defined as elevated when >12mm Hg. Transthoracic echocardiographic parameters and LAEI were measured offline, blinded to RHC results. In the derivation cohort, LAEI correlated logarithmically with PCWP, and the log-transformed LAEI (lnLAEI) correlated linearly with PCWP (r=-0.73, P<.001). lnLAEI showed an independent and additive predictive role for PCWP estimation over clinical and diastolic dysfunction (DD) parameters. The diagnostic accuracy of lnLAEI for elevated PCWP identification (area under the curve=0.875, P<.001; optimal lnLAEI cutoff<4.02) was higher than either the single DD parameters or their combination. In the validation cohort, lnLAEI cutoff < 4.02 showed higher accuracy than the 2016 DD algorithm (88% vs 74%) for elevated PCWP identification. Finally, the equation PCWP=38.3 - 6.2×lnLAEI, obtained from the derivation cohort, predicted invasively measured PCWP in the validation cohort. In a cohort of patients with various chronic cardiac diseases, lnLAEI performed better than DD parameters and the 2016 DD algorithm for PCWP estimation. lnLAEI might be a useful echocardiographic parameter for noninvasive PCWP estimation.

Added value of left atrial expansion index for non-invasive estimation of pulmonary capillary wedge pressure

Abstract Introduction Right heart catheterization (RHC) is the reference technique for pulmonary capillary wedge pressure (PCWP) measurement but remains invasive. Transthoracic echocardiography (TTE) diastolic parameters (DPs) are used as non-invasive surrogates but have suboptimal accuracy. Left atrial expansion index (LAEI), describing LA reservoir function, could be used for indirectly estimate PCWP. Purpose To evaluate the correlation between LAEI and PCWP and to compare LAEI accuracy against DPs in estimating PCWP. Methods We retrospectively included the patients admitted to our department from 05/2015 to 02/2018 who underwent both a clinically indicated RHC and TTE within 24 hours. PCWP was obtained during RHC. DPs were measured offline and LAEI was calculated from LA maximum volume (MaxVol) and LA minimum volume (MinVol) as LAEI = [(LAMaxVol − LAMinVol) / LAMinVol)] × 100. Results We enrolled 405 patients (left ventricular ejection fraction (LVEF)&amp;lt;50% n=172; PCWP&amp;gt;12mmHg n=209). LAEI showed a logarithmic correlation with PCWP. The log-transformed LAEI (lnLAEI) had an excellent linear correlation (r=−0.82; p&amp;lt;0.001) with PCWP, higher than DPs (LAMaxVoli: r=0.42; E/A: r=0.57; E/e': r=0.51; TRMaxVel r=0.17; all p&amp;lt;0.001). lnLAEI had the highest accuracy in identifying PCWP&amp;gt;12 mmHg (lnLAEI AUC 0.921, p&amp;lt;0.001) when compared to DPs and their association (Figure). lnLAEI showed an independent and added predictive value in estimating PCWP in a model including atrial fibrillation (Afib), heart rate (HR), LVEF, mitral regurgitation (MR), LAMaxVoli, E/A, E/e' and TRMaxVel (Table). Conclusions LAEI is a simple parameter strongly associated with PCWP which might be used for PCWP estimation. Funding Acknowledgement Type of funding source: None

Echo Doppler Estimation of Pulmonary Capillary Wedge Pressure in Patients with Severe Aortic Stenosis.

Transcatheter aortic valve replacement (TAVR) has become a treatment option for patients with severe aortic stenosis (AS) and high surgical risk. Assessment of symptoms in these patients is challenging because of advanced age, comorbidities, and limited physical activity. Noninvasive quantification of pulmonary capillary wedge pressure (PCWP) in candidates for TAVR may be helpful for risk stratification. The objective of the study was to create a model for estimation of PCWP by echo Doppler in patients with severe AS. Data from 80 patients with severe AS referred for TAVR were used to develop an echo Doppler model for predicting PCWP. Its performance was evaluated in the test cohort of 33 patients who had invasive and noninvasive evaluation. No single echo Doppler parameter estimated PCWP accurately. In the retrospective analysis, the multilinear regression provided an accurate estimate of PCWP (r(2) = 0.74). The model included, in order of importance (all P < 0.05), the ratio of early transmitral velocity (E) to annular velocity (E'), the left ventricular ejection fraction, and the velocity time integral of tricuspid regurgitation signal. In the prospective cohort of patients with severe AS, the model demonstrated good predictive ability of PCWP (r = 0.77, P < 0.01). In patients with severe AS, noninvasive estimation of PCWP is possible by integration of two-dimensional, spectral, and tissue Doppler variables.

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.

Usefulness of Tissue Doppler Imaging to Evaluate Pulmonary Capillary Wedge Pressure During Exercise in Patients With Reduced Left Ventricular Ejection Fraction

The early diastolic transmitral velocity/tissue Doppler imaging mitral annular early diastolic velocity (E/e') ratio is used to estimate left ventricular (LV) filling pressures at rest. However, there are only limited data that validate its use during exercise. Accordingly, the aim of this study was to test the ability of E/e' to estimate pulmonary capillary wedge pressure (PCWP) during symptom-limited exercise in patients with LV systolic dysfunction. Forty patients with severe LV dysfunction and heart failure symptoms (54 ± 12 years, 28 men) underwent simultaneous Doppler assessment of E/e' and right-sided cardiac catheterization at rest and during a symptom-limited exercise test, at steady state levels of 30%, 60%, and 90% of their maximal exercise capacity. During exercise, all 40 patients successfully completed stage 1, yielding 40 pairs of data for comparison. Eighteen patients also successfully completed stage 2, and 5 patients also made it through stage 3, yielding 23 additional data pairs. In total, there were thus 63 pairs of data available during exercise. With exercise, heart rate increased from 77 ± 14 to 112 ± 21 beats/min. Septal E/e' at rest correlated well with PCWP at rest (r = 0.75, p <0.01). PCWP at rest also correlated with resting mitral deceleration time (r = 0.32, p <0.01) and with the transmitral E/A ratio (r = 0.74, p <0.01). During exercise, the correlation between septal E/e' and PCWP was weaker (r = 0.57, p <0.01) and was shifted to the right. This rightward shift was observed in patients with both separated or merged E and A velocities. In conclusion, in patients with severe LV dysfunction, although E/e' allows accurate estimation of PCWP at rest, it appears less reliable for estimating LV filing pressure during exercise.

Usefulness of Tissue Doppler Imaging for Assessing Left Ventricular Filling Pressure in Patients With Stable Severe Systolic Heart Failure

The ratio of early transmitral blood flow velocity over tissue Doppler early diastolic mitral annulus velocity (E/e') was found unreliable for estimating pulmonary capillary wedge pressure (PCWP) in patients with decompensated systolic heart failure (HF). The objective of this study was to test its reliability in stable HF. Therefore, 130 consecutive patients with a left ventricular (LV) ejection fraction of <35% and stable HF underwent right-sided cardiac catheterization and transthoracic echocardiography with measurement of transmitral flow velocities (E, A) and mitral annulus velocities during systole (s') and diastole (e'). Mean age was 56 ± 11 years and mean LV ejection fraction was 28 ± 8%; 48% had PCWP of >15 mm Hg. E/e'septal correlated more strongly with PCWP (r = 0.53) compared with E/e'lateral (r = 0.41) and E/e'mean (r = 0.50; all p values <0.001). The area under the receiver operating characteristic curve (AUC) of E/e' ratios for PCWP estimation was 0.79 (95% confidence interval [CI] 0.70 to 0.87) for E/e'septal, 0.72 (95% CI 0.63 to 0.82) for E/elateral, and 0.79 (95% CI 0.70 to 0.87) for E/emean (all p values <0.0001). AUCs of E/eseptal and E/emean did not vary with s'septal, QRS width, or resynchronization. Using a cutoff of 8, negative predictive value of E/e'septal was 89% and negative likelihood ratio of 0.15. E/e'lateral showed good diagnostic performance only in patients with s'lateral of >4.5 cm/s (n = 77, 59%; AUC = 0.82; 95% CI 0.71 to 0.92; s'lateral of ≤4.5 cm/s: AUC = 0.54; 95% CI 0.38 to 0.70; p = 0.005). In conclusion, e' is useful for estimating LV filling pressure in stable severe systolic HF. E/e'septal showed good diagnostic performance for detecting normal filling pressures.

Noninvasive estimation of pulmonary capillary wedge pressure using speckle tracking echocardiography in patients with preserved or reduced ejection fraction

Purpose: Echocardiographic parameters such as a ratio of early mitral inflow velocity (E) to atrial contraction flow velocity (A) and a ratio of E to mitral annular tissue velocity (e') were proposed to estimate left ventricular (LV) diastolic function and pulmonary capillary wedge pressure (PCWP). However, E/A and E/e' have limitations to use in various conditions. Noninvasive estimation of PCWP has not been elucidated. We have recently developed a novel index to estimate PCWP using left atrial (LA) emptying function (EF) and volume (LAV) assessed by speckle tracking echocardiography (STE) and named it kinetics-tracking (KT) index: log (active LAEF/ minimum LAV index). The estimated PCWP (ePCWP) was determined as 10.7 – 12.4 × KT index. The aim was to examine the usefulness of KT index in patients with preserved or reduced ejection fraction to estimate PCWP measured by cardiac catheterization. Methods: We measured phasic LAV and EF obtained from time-LA volume curves by STE during sinus rhythm in consecutive 128 patients (age 67±12, 80 men, 77 patients with LV ejection faction ≥55%) just before cardiac catheterization. Patients with atrial fibrillation, severe mitral regurgitation and mitral stenosis were excluded. LA volume and EF and E/e' were compared with PCWP measured by cardiac catheterization. Moreover, ePCWP estimated by 4 combinations of LA maximum or minimum volume and LA total or active EF was compared with PCWP by cardiac catheterization. Results: The maximum and minimum LAV index were correlated with PCWP (r=0.71 and r=0.78, respectively, p 15 mmHg were 95 and 88%, respectively (AUC = 0.97) using KT index of 17.8 as an optimal cutoff value. In multivariate regression analysis, only KT index was an independent parameter to estimate PCWP by cardiac catheterization in 128 subjects. Conclusions: For noninvasive estimation of LV diastolic function, the KT index is a novel and more accurate predictor of PCWP than LA function, volume solely or E/e'. KT index have an incremental value in routine clinical practice.

Elevated left ventricular filling pressures can be estimated with accuracy by a new mathematical model

Although the clinical assessment of jugular venous pressure (JVP) provides accurate estimate of right atrial pressure (RAP), there is no reliable non-invasive method for assessing pulmonary capillary wedge pressure (PCWP). Our objective was to evaluate the sensitivity and specificity for detecting elevated left ventricular filling pressures using a model for PCWP estimation, based on the clinical assessment of RAP and association between RAP and PCWP, which is unique for each patient, identified in a recent right heart catheterization (RHC). The study included 377 patients (age, 54.3 ± 13 years) with heart failure with reduced ejection fraction (left ventricular ejection fraction of 30.5 ± 10.8%) who underwent 2 RHCs within 1 year. In Group A (189 randomly selected patients), hemodynamic variables with significant correlation with the current wedge pressure (PCWP(2)) were identified and an equation estimating PCWP(2) based on these variables was formed. The validity of the equation was evaluated in the remaining 188 patients (Group B). The equation was also evaluated, prospectively in 39 new patients where RAP was estimated clinically, by physicians blinded to the results of the RHC. PCWP(2) in Group A correlated with RAP(1), systolic pulmonary artery pressure (SPAP(1)), and PCWP(1) of the first RHC and with RAP(2) and SPAP(2) of the second. The equation is PCWP(2) = [3RAP(2) + (PCWP(1) - RAP(1)) + 4]/2. In Group B, the sensitivity and specificity of estimated PCWP(2) for diagnosis of elevated LV filling pressures (invasive values >18 mm Hg) was significant, reflected by an area under the curve (AUC) of 0.954 (p < 0.001). In the prospective sub-group, where JVP was entered in the formula as an estimate of RAP(2), correlation between estimated and measured PCWP(2) was r = 0.803 (p < 0.001). The current PCWP of a patient with heart failure can be estimated accurately by a simple equation based on measurements of a previous RHC and the current value of clinically assessed JVP.

Pulmonary capillary wedge pressure estimation by Doppler echocardiography and cardiac catheterization: a study at a tertiary level hospital in Bangladesh

Background: Doppler echocardiography is a valuable tool for the non-invasive evaluation of diastolic function. This study aimed to correlate the pulmonary capillary wedge pressure (PCWP) estimated by Doppler echocardiography.

Ratio of Early Transmitral Velocity to Lateral Mitral Annular Early Diastolic Velocity Has the Best Correlation With Wedge Pressure Following Cardiac Surgery

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. 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). 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.

Diagnosing heart failure in aortic valve stenosis.

In aortic valve stenosis (AS), heart failure (HF) omens a high risk of death and is an indication for prompt valve replacement. We studied whether its detection can be facilitated by measuring plasma N-terminal B-type natriuretic peptide (Nt-BNP) or by estimating pulmonary capillary wedge pressure (PCWP) using echocardiography. A cross-sectional cohort study in a university hospital. We studied 137 consecutive adult patients referred to our unit for invasive evaluation of isolated AS. All patients underwent cardiac catheterization, measurement of plasma Nt-BNP and estimation of PCWP by Doppler echocardiography of transmitral and pulmonary venous flow velocities. The final diagnosis of HF was based on the combined criteria of dyspnoea on ordinary effort and PCWP >14 mmHg at cardiac catheterization. The performance of Nt-BNP and the PCWP estimate in the detection of HF were studied using receiver operating characteristic (ROC) analysis. Totally 42 patients had HF. A cardiologist's clinical diagnosis of HF had high specificity (94%) but poor sensitivity (66%). With an optimized cut-off point, plasma Nt-BNP had moderate sensitivity (77%) and specificity (79%) for HF; the ROC area was 0.83. The echocardiographic PCWP estimate classified 90% of patients correctly as having normal or truly elevated (>14 mmHg) PCWP. Its sensitivity and specificity for the diagnosis of HF were 80 and 95% respectively; the ROC area was 0.88. With a cut-off point of 12 mmHg, the sensitivity of the PCWP estimate was 85% and specificity, 88%. The recognition of HF in patients with AS can be improved by estimating PCWP using Doppler echocardiography of transmitral and pulmonary venous flow velocities.

Echocardiographic Doppler assessment of pulmonary capillary wedge pressure in surgical patients with postoperative circulatory shock and acute lung injury.

In cardiac patients, pulmonary capillary wedge pressure (PCWP) is estimated using color M-mode Doppler study of left ventricular filling and Doppler tissue imaging. The goal of this study was to assess whether echocardiography accurately estimates PCWP in critically ill patients. Sixty ventilated patients admitted for septic shock and acute lung injury were prospectively studied using simultaneously transesophageal echocardiography and pulmonary artery catheterization. Initial PCWP values and their changes measured invasively were compared to initial values and corresponding changes of early diastolic velocity of mitral annulus displacement measured by Doppler tissue imaging (Ea), flow propagation velocity of early diastolic mitral inflow measured by color M-mode Doppler (Vp), and their respective ratio to early mitral inflow velocity (E) measured by conventional Doppler: E/Ea and E/Vp. Relations between E/Ea, E/Vp, and PCWP were prospectively tested in 20 additional patients. E/Ea and E/Vp gave a rough estimate of initial PCWP values with mean biases of 0.4 +/- 2.2 and 0.1 +/- 2.9 mmHg, respectively. Receiving operating characteristic curves demonstrated that an E/Ea of 6 or greater is an accurate predictor of a PCWP of 13 mmHg or greater and that an E/Ea of 5.4 is a good predictor of a PCWP of 8 mmHg or less. Changes in PCWP were significantly correlated to changes in E/Ea (Rho = 0.84, P < 0.0001). In patients with postoperative circulatory shock and acute lung injury, transesophageal echocardiography estimates noninvasively PCWP. However, echocardiographic estimation of PCWP may not be accurate enough for adjusting therapy.

Contrast-enhanced Doppler hemodynamics for noninvasive assessment of patients with chronic heart failure and left ventricular systolic dysfunction

We sought to evaluate whether contrast-enhanced Doppler echocardiography can improve the noninvasive estimation of hemodynamic variables in left ventricular (LV) dysfunction. Right-heart catheterization and Doppler echocardiography were simultaneously performed in 45 patients with LV dysfunction (ejection fraction: 29 ± 7%) in sinus rhythm. Noninvasive variables were estimated as follows: cardiac output by pulsed Doppler of LV outflow tract; pulmonary capillary wedge pressure by a regression equation including mitral and pulmonary venous flow variables; pulmonary artery mean pressure from the calculated systolic and diastolic pulmonary artery pressures; and pulmonary vascular resistance from the previous measurements according to hemodynamic definition. Contrast enhancement increased the feasibility of pulmonary capillary wedge pressure estimation from 60% to 100%; of pulmonary artery mean pressure from 42% to 91%; and of pulmonary vascular resistance from 42% to 91%. Strong correlations between invasive and noninvasive hemodynamic variables were found: r = 0.90, standard error of the estimate (SEE) 0.45 L/min for cardiac output; r = 0.90, SEE 3.1 mm Hg for pulmonary capillary wedge pressure; r = 0.93, SEE 3.7 mm Hg for pulmonary artery mean pressure; and r = 0.85 SEE 1.0 Wood units for pulmonary vascular resistance. Weaker correlations for PAMP (r = 0.82, SEE 5.6 mm Hg) and PVR (r = 0.66, SEE 1.7 Wood units) were apparent prior to contrast enhancement. When patients were separated according to PVR threshold values, the contrast allowed the correct placement of 88% of patients, whereas only 57% were correctly assigned without it. The contrast increased accuracy and reduced interobserver variability in the evaluation of hemodynamic variables. The contrast-enhanced study is capable of increasing the value of noninvasive hemodynamic assessment in LV dysfunction. (J Am Soc Echocardiogr 2003;16:124-31.)

Mitral inflow and pulmonary venous Doppler measurements do not predict pulmonary capillary wedge pressure in heart transplant recipients

Background: Noninvasive estimation of pulmonary capillary wedge pressure (PCWP) with Doppler-derived mitral inflow pattern has been shown to correlate well with invasively measured PCWP; however, it has not yet been determined whether Doppler-derived mitral inflow pattern can be used to estimate PCWP accurately in heart transplant recipients. Methods: To determine if mitral and pulmonary venous inflow data can be applied to calculate PCWP in heart transplant recipients, same-day echocardiograms and right heart catheterizations were reviewed and 83 echocardiograms with adequate mitral inflow patterns in 53 patients were studied. Twenty-eight studies that also had adequate pulmonary venous inflow patterns were selected for offline analysis. Results: Using a previously published formula [PCWP = 17 + (5.3 × E/A) – (0.11 × IVRT)], where E/A is the ratio of early to late mitral inflow velocities and IVRT is the isovolumic relaxation time, we derived a calculated PCWP, the results of which compared poorly with the measured PCWP ( r = 0.33; p = 0.002). Linear regression analysis of measured PCWP versus mitral inflow Doppler flow velocity parameters also revealed poor to modest correlation. Adding parameters derived from the pulmonary venous inflow patterns failed to improve this correlation. Conclusion: Doppler-derived estimation of PCWP with mitral and pulmonary venous inflow patterns cannot be used to reliably predict PCWP in heart transplant recipients. (Am Heart J 1998;135:641-6.)

What is the most appropriate variable for estimation of mean pulmonary capillary wedge pressure by transesophageal pulsed Doppler echocardiography?

Although left ventricular (LV) inflow and pulmonary venous (PV) flow variables estimated by transesophageal Doppler echocardiography (TEE) reflect pulmonary capillary wedge pressure (PCWP), they are also affected by changes in cardiac function. The purpose of the present study was to detect the most appropriate variable for the estimation of PCWP by TEE in patients (pts) with ischemic heart disease. Several variables of LV inflow and left upper PV flow were compared with PCWP in 36 pts (six with angina pectoris and 30 with old myocardial infarction). Early diastolic flow (E) and atrial contraction flow (A) were used as LV inflow, while systolic forward flow (X), diastolic forward flow (Y) and atrial contractile reversal flow (z) were used as PV flow. The peak velocity of each flow wave (Ep, Ap, Xp, Yp, and Zp) and the time-velocity integral (Ei, Ai, Xi, Yi, and Zi) were measured. The ratio of Ep to Ap (Ep/Ap), Ei to Ai (Ei/Ai), Xp to Yp (Xp/Yp), Xi to Yi (Xi/Yi), Zp to Ap (Zp/Ap), Zi to Ai (Zi/Ai) and the systolic fraction of PV forward flow were calculated. Among these variables, the Zi/Ai ratio was most strongly correlated with PCWP (R = 0.80). The Zi/Ai ratio may not be influenced by atrial function because the augmentation of atrial pump function increases Zi as well as Ai, and this may be one reason why the ratio correlated well with PCWP. The Zi/Ai ratio is a new useful variable for estimating PCWP by TEE.

Noninvasive Estimation of Pulmonary Capillary Wedge Pressure from Pulmonary Venous Flow Using Transesophageal Doppler Echocardiography

We prospectively examined the relationship between pulmonary venous flow velocity determined by transesophageal echocardiography and pulmonary capillary wedge pressure (PCWP) determined with a Swan-Ganz catheter in 40 consecutive patients who were all in sinus rhythm and without significant mitral valve disease. Correlations were assessed between the four components of pulmonary venous flow – atrial reversal flow (A), early systolic (SI) and late systolic (S2) forward flow, and diastolic forward flow (D) – and PCWP. Multiple regression analysis showed that PCWP could be estimated from only two (S2 and D) among these four components. Thus, PCWP was estimated by using the following equation with a strong correlation (r = 0.83) to measured one by catheterization: PCWP = –0.07 × S2+0.27 × D+2.3 mm Hg. In addition, prospective estimation of PCWP by this equation in an additional 25 patients gave a good correlation with the measured values (r = 0.83). PCWP can be estimated by our new equation using the peak velocity of late systolic forward and diastolic forward flow in pulmonary vein in patients with various types of heart diseases.