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

Pulmonary artery acceleration time in young children is determined by heart rate and transpulmonary gradient but not by pulmonary blood flow: A simultaneous echocardiography-cardiac catheterization study

INTRODUCTION

Pulmonary artery acceleration time (PAAT) is considered useful for the non-invasive evaluation of pulmonary artery pressure (PAP) and pulmonary vascular resistance (PVR). PAAT is dependent on PAP, PVR, pulmonary artery compliance, stroke volume, and heart rate. Its relative dependency on these determinants may differ between young and older children, raising uncertainty regarding its utility in young children. We aim to identify the primary determinants of the PAAT in children less than 36 months undergoing cardiac catheterization and its utility for the diagnosis of elevated PVR.

METHODS

We prospectively studied 42 children undergoing cardiac catheterization and simultaneous echocardiography. We determined the correlations of PAAT to the above-mentioned determinants and evaluated receiver operator characteristic (ROC) curves for diagnosis of PVR indexed to body surface area (PVRi) ≥3 Wu*m² .

RESULTS

Median age was 11.5 (IQR 5.2, 21.2) months. Moderate correlations were found between PAAT and mean PAP (R = -.66, p < .001), PVRi (R = -.54, p = .004), pulmonary artery compliance (R = .65, p < .001), transpulmonary gradient (R = -.67, p < .001), stroke volume (R = .61, p = .002), and heart rate (R = -.63, p < .001). In multivariate regression modeling, only transpulmonary gradient and heart rate were independent determinants of PAAT. PAAT ≤77 msec had acceptable utility for diagnosing PVRi ≥ 3 Wu*m² (AUC .8 [.64, .95], n = 36), low sensitivity (59%), and excellent specificity (94%).

CONCLUSION

Transpulmonary gradient and heart rate, but not pulmonary blood flow, are important determinants of PAAT in children <36 months undergoing cardiac catheterization. PAAT has low sensitivity for diagnosing elevated PVRi, therefore, should not be solely relied upon in screening for elevated PVRi in young children.

Transthoracic Right Heart Echocardiography for the Intensivist

BACKGROUND

The impact of critical illness on the right ventricle (RV) can be profound and RV dysfunction is associated with mortality. Intensivists are becoming more facile with bedside echocardiography, however, pedagogy has largely focused on left ventricular function. Here we review measurements of right heart function by way of echocardiographic modalities and list clinical scenarios where the RV dysfunction is a salient feature.

MAIN

RV dysfunction is heterogeneously defined across many domains and its diagnosis is not always clinically apparent. The RV is affected by conditions commonly seen in the ICU such as acute respiratory distress syndrome, pulmonary embolism, RV ischemia, and pulmonary hypertension. Basic ultrasonographic modalities such as 2D imaging, M-mode, tissue Doppler, pulsed-wave Doppler, and continuous Doppler provide clinicians with metrics to assess RV function and response to therapy.

CONCLUSION

The right ventricle is impacted by various critical illnesses with substantial mortality and mortality. Focused bedside echocardiographic exams with attention to the right heart may provide intensivists insight into RV function and provide guidance for patient management.

Clinical Utility of Echocardiography in Former Preterm Infants with Bronchopulmonary Dysplasia

BACKGROUND

The clinical utility of echocardiography for the diagnosis of pulmonary vascular disease (PVD) in former preterm infants with bronchopulmonary dysplasia (BPD) is not established. Elevated pulmonary vascular resistance (PVR) rather than pulmonary artery pressure (PAP) is the hallmark of PVD. We evaluated the utility of echocardiography in infants with BPD in diagnosing pulmonary hypertension and PVD (PVR >3 Wood units × m²) assessed by cardiac catheterization.

METHODS

A retrospective single center study of 29 infants born ≤29 weeks of gestational age with BPD who underwent cardiac catheterization and echocardiography was performed. PVD was considered present by echocardiography if the tricuspid valve regurgitation jet peak velocity was >2.9 m/sec, post-tricuspid valve shunt systolic flow velocity estimated a right ventricular systolic pressure >35 mm Hg, or systolic septal flattening was present. The utility (accuracy, sensitivity, and positive predictive value [PPV]) of echocardiography in the diagnosis of PVD was tested. Subgroup analysis in patients without post-tricuspid valve shunts was performed. Echocardiographic estimations of right ventricular pressure, dimensions, function, and pulmonary flow measurements were evaluated for correlation with PVR.

RESULTS

The duration between echocardiography and cardiac catheterization was a median of 1 day (interquartile range, 1-4 days). Accuracy, sensitivity, and PPV of echocardiography in diagnosing PVD were 72%, 90.5%, and 76%, respectively. Accuracy, sensitivity, and PPV increased to 93%, 91.7%, and 100%, respectively, when infants with post-tricuspid valve shunts were excluded. Echocardiography had poor accuracy in estimating the degree of PAP elevation by cardiac catheterization. In infants without post-tricuspid valve shunts, there was moderate to good correlation between indexed PVR and right ventricular myocardial performance index (rho = 0.89, P = .005), systolic to diastolic time index (0.84, P < .001), right to left ventricular diameter ratio at end systole (0.66, P = .003), and pulmonary artery acceleration time (0.48, P = .05).

CONCLUSIONS

Echocardiography performs well in screening for PVD in infants with BPD and may be diagnostic in the absence of a post-tricuspid valve shunt. However, cardiac catheterization is needed to assess the degree of PAP elevation and PVR. The diagnostic utility of echocardiographic measurements that correlate with PVR should be evaluated prospectively in this patient population.

ACVIM consensus statement guidelines for the diagnosis, classification, treatment, and monitoring of pulmonary hypertension in dogs

Pulmonary hypertension (PH), defined by increased pressure within the pulmonary vasculature, is a hemodynamic and pathophysiologic state present in a wide variety of cardiovascular, respiratory, and systemic diseases. The purpose of this consensus statement is to provide a multidisciplinary approach to guidelines for the diagnosis, classification, treatment, and monitoring of PH in dogs. Comprehensive evaluation including consideration of signalment, clinical signs, echocardiographic parameters, and results of other diagnostic tests supports the diagnosis of PH and allows identification of associated underlying conditions. Dogs with PH can be classified into the following 6 groups: group 1, pulmonary arterial hypertension; group 2, left heart disease; group 3, respiratory disease/hypoxia; group 4, pulmonary emboli/pulmonary thrombi/pulmonary thromboemboli; group 5, parasitic disease (Dirofilaria and Angiostrongylus); and group 6, disorders that are multifactorial or with unclear mechanisms. The approach to treatment of PH focuses on strategies to decrease the risk of progression, complications, or both, recommendations to target underlying diseases or factors contributing to PH, and PH‐specific treatments. Dogs with PH should be monitored for improvement, static condition, or progression, and any identified underlying disorder should be addressed and monitored simultaneously.

Usefulness of the Continuous-Wave Doppler-Derived Pulmonary Arterial-Right Ventricular Pressure Gradient Just before Atrial Contraction for the Estimation of Pulmonary Arterial Diastolic and Wedge Pressures

In our new echocardiographic method, pulmonary regurgitant velocity immediately before right atrial (RA) contraction is used to estimate pulmonary artery diastolic pressure (PADP) and mean PA wedge pressure (MPAWP). Our aim here was to compare the usefulness of this new method with that of the conventional method, which uses pulmonary regurgitant velocity at end diastole. We studied 55 consecutive patients who underwent echocardiography and right-sided heart catheterization. The pulmonary regurgitant velocities just before RA contraction and at end diastole were measured to obtain echocardiographic estimates of PADP (EPADP_preA and EPADP_ED, respectively) by adding the pressure gradients to the echocardiographically estimated RA pressure. Compared with EPADP_ED, EPADP_preA correlated better with PADP (r = 0.87) and MPAWP (r = 0.80), and direct fixed biases were detected for EPADP_ED but not for EPADP_preA. The area under the receiver operating characteristic curve distinguishing patients with MPAWP ≥18 mm Hg was greater for EPADP_preA (0.97) than for E/e' (0.94) and E/A (0.83). EPADP_preA is thus useful in estimating PADP and MPAWP in patients with heart disease.

The right ventricle under pressure: evaluating the adaptive and maladaptive changes in the right ventricle in pulmonary arterial hypertension using echocardiography (2013 Grover Conference series)

The importance of the right ventricle (RV) in pulmonary arterial hypertension (PAH) has been gaining increased recognition. This has included a reconceptualization of the RV as part of an RV-pulmonary circulation interrelated unit and the observation that RV function is a major determinant of prognosis in PAH. Noninvasive imaging of RV size and function is critical to the longitudinal management of patients with PAH, and continued understanding of the pathophysiology of pulmonary vascular disease relies on the response of the RV to pulmonary vascular remodeling. Echocardiography, in particular the newer echocardiographic measurements and techniques, allows easy, readily accessible means to assess and follow RV size and function.

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.

C-reactive protein, diastolic dysfunction, and risk of heart failure in patients with coronary disease: Heart and Soul Study

BACKGROUND

High-sensitivity C-reactive protein (CRP) is an inflammatory marker that predicts coronary heart disease (CHD) and, in recent studies, incident heart failure (HF). Whether the association of inflammation with incident HF is explained by worse baseline left ventricular dysfunction or by underlying CHD is unknown.

METHODS AND RESULTS

Serum CRP was measured in a cohort of 985 outpatients with established CHD from the Heart and Soul Study. During 3 years of follow-up, 15% of the participants with elevated CRP levels (>3 mg/L) were hospitalised for HF, compared with 7% of those with CRP <or= 3 mg/L. In multivariate analysis, elevated CRP was associated with HF after adjustment for traditional risk factors, baseline CHD severity and interim MI (adjusted HR 2.1, 95% CI, 1.2-3.6; p=0.009). However, elevated CRP was no longer associated with HF after further adjustment for the presence of diastolic dysfunction on echocardiography (adjusted HR 1.6, 95% CI, 0.8-3.2; p=0.1).

CONCLUSIONS

Among outpatients with stable CHD, elevated CRP levels predict hospitalisation for heart failure, independent of baseline heart failure, medication use, CHD severity, and subsequent MI events. This relationship appears to be at least partly explained by abnormal diastolic function in patients with elevated CRP levels.

Association of African American race with elevated pulmonary artery diastolic pressure: data from the Heart and Soul Study

BACKGROUND

Whether increased severity of heart failure in African Americans is a result of differences in cardiac physiology is uncertain. The end-diastolic pulmonary regurgitation (EDPR) gradient is associated with abnormal cardiac physiology. We hypothesized that African American race is associated with an elevated EDPR gradient that may partially predispose African Americans to heart failure.

METHODS

The Heart and Soul Study prospectively assessed the EDPR gradient in 480 patients with coronary disease. We used multivariable linear regression to investigate the independent association of African American race with EDPR gradient.

RESULTS

Compared with 393 non-African Americans, the 87 African Americans had similar indices of left ventricular systolic and diastolic function, left ventricular mass index, mitral regurgitation, peak tricuspid regurgitation gradient, and pulmonary velocity time integral. However, the EDPR gradient was significantly higher in African Americans (4.2 +/- 3.3 mm Hg) than in Caucasians (3.1 +/- 2.5 mm Hg) or other racial groups (3.5 +/- 2.7 mm Hg) (P = .008). In a multivariable model, African American race was a significant predictor of elevated EDPR gradient (beta coefficient 0.75, P = .03).

CONCLUSION

African American race is independently associated with an elevated EDPR gradient in patients with coronary artery disease.

Elevated pulmonary artery pressure by Doppler echocardiography predicts hospitalization for heart failure and mortality in ambulatory stable coronary artery disease: the Heart and Soul Study

OBJECTIVES

We compared the predictive ability of tricuspid regurgitation (TR) and end-diastolic pulmonary regurgitation (EDPR) gradients in outpatients with coronary artery disease.

BACKGROUND

The TR and EDPR gradients, in conjunction with right atrial pressure, provide Doppler estimates of pulmonary artery systolic and diastolic pressures. We hypothesized that increases in TR or EDPR gradients in stable coronary artery disease would predict heart failure (HF) hospitalization or cardiovascular (CV) death.

METHODS

We measured TR and EDPR gradients in 717 adults with completed outcome adjudications who were recruited for the Heart and Soul Study. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for HF hospitalization, CV death, all-cause death, and the combined end point. Multivariate adjustments were made for age, gender, race, history of CV or pulmonary disease, functional class, and left ventricular ejection fraction.

RESULTS

There were 63 HF hospitalizations, 19 CV deaths, and 86 all-cause deaths at the 3-year follow-up. There were 466 measurable EDPR gradients and 573 measurable TR gradients. Age-adjusted ORs for EDPR >5 mm Hg predicted HF hospitalization (2.7, 95% CI 1.3 to 5.5, p = 0.006), all-cause death (2.5, 95% CI 1.4 to 4.4, p = 0.002), and HF hospitalization or CV death (2.7, 95% CI 1.4 to 5.2, p = 0.004). Age-adjusted OR for TR >30 mm Hg predicted HF hospitalization (3.4, 95% CI 1.9 to 6.2, p < 0.0001) and HF hospitalization or CV death (3.0, 95% CI 1.7 to 5.3, p = 0.0001). Multivariate adjusted OR per 5-mm Hg incremental increases in EDPR predicted HF hospitalization or CV death (1.9, 95% CI 1.01 to 3.6, p = 0.046) and all-cause death (1.7, 95% CI 1.05 to 2.8, p = 0.03). Multivariate adjusted OR per 10-mm Hg incremental increases in TR predicted HF hospitalization or CV death (1.6, 95% CI 1.1 to 2.4, p = 0.008).

CONCLUSIONS

Increases in EDPR or TR gradients predict HF hospitalization or CV death among ambulatory adults with coronary artery disease.

Pulmonary regurgitation end-diastolic gradient is a Doppler marker of cardiac status: data from the Heart and Soul Study

BACKGROUND

Echocardiograms routinely sample pulmonary regurgitation signals from which it is possible to measure end diastolic gradients; these correlate with pulmonary artery diastolic pressures.

METHODS

We performed echocardiograms in 741 ambulatory adults with coronary artery disease who were recruited for the Heart and Soul Study. We compared indicators of cardiac status among individuals with normal (0-5.0 mm Hg) and elevated (> 5.0 mm Hg) end diastolic pulmonary regurgitation (EDPR) gradients.

RESULTS

Of the 481 participants with measurable EDPR gradients, 21% had elevated EDPR gradients (> 5.0 mm Hg). EDPR gradients > 5.0 mm Hg were associated with higher New York Heart Association functional class (P = .002), higher brain natriuretic peptide (P = .002), fewer metabolic equivalents achieved on treadmill testing (P < 0.001), and higher left ventricular mass (P < 0.001). The EDPR gradient > 5.0 mm Hg had a sensitivity of 25% (95% confidence interval 20-30%) and a specificity of 86% (80-91%) for detecting at least one of the following: systolic dysfunction, diastolic dysfunction, or abnormal wall motion score. The EDPR gradient > 5.0 mm HG was statistically equivalent to the tricuspid regurgitation (TR) gradient > 30 mm Hg in terms of diagnostic value (area under the receiver operating characteristic curve equaled 0.58 for each test). The EDPR gradient increased the yield of pulmonary artery pressures from 61% (TR gradient alone) to 84% (P < .0001).

CONCLUSION

The EDPR gradient provides valuable information independent of the TR gradient in evaluating pulmonary artery pressures and cardiac dysfunction.

Two simple echo-Doppler measurements can accurately identify pulmonary hypertension in the large majority of patients with chronic heart failure

BACKGROUND

The assessment of pulmonary hypertension in patients with heart failure is of great clinical importance not only for diagnostic purposes but also for prognostication. The present study was undertaken on a consecutive basis with a group of patients with chronic heart failure. Patients were evaluated for their suitability for heart transplantation: (1) to explore the diagnostic accuracy of several echo Doppler parameters of pulmonary hemodynamics in predicting the presence of elevated pulmonary artery pressure (defined as pulmonary artery systolic pressure > or =35 mmHg and mean pulmonary artery pressure >20 mmHg); (2) to assess the diagnostic ability of the same parameters to identify patients with elevated pulmonary vascular resistance; and (3) to evaluate the influence of right ventricular function and degree of tricuspid regurgitation in modifying diagnostic accuracy.

METHODS

Echo Doppler examination and right heart catheterization were performed consecutively within 24 hours in 86 patients. The optimal cut-off value for a series of echo Doppler parameters capable of identifying patients with pulmonary hypertension was obtained by dividing the entire sample into 2 groups; the optimal threshold (highest sensitivity and specificity) of the echo and Doppler parameters used to classify patients with and without pulmonary hypertension was determined in 67% of cases by means of the receiver operating characteristic (ROC) curve: this was the testing sample. The proportion of cases classified correctly according to the selected cut-off was computed. The remaining 33% of cases represented the validation sample: sensitivity, specificity and predictive values (and their 95% confidence intervals [CIs]) for identifying pulmonary hypertension were calculated from the proposed cut-offs in this second sample. Finally, the overall performance of the echo Doppler parameters was assessed over the whole sample by considering the extent of the area under the ROC curve (A-ROC) and its 95% CI, for the dichotomic measurement.

RESULTS

On right heart catheterization, a pulmonary artery systolic (PAPs) pressure > or =35 mmHg plus a mean pressure (mean PAP) >20 mmHg was documented in 49 of 86 cases (57%), for whom mean values were 56 +/- 17 and 38 +/- 11 mmHg, respectively. The proportion of cases identified correctly as having pulmonary hypertension was highest for PAPs (88%) and mean PAP (85%) in addition to acceleration time of pulmonary artery systolic flow (ACT) (79%) and pulmonary artery diastolic pressure obtained utilizing the early phase of the tricuspid regurgitation spectral flow (PAPd/TR) (75%). PAPd/TR performed better in the validating sample in terms of diagnostic ability, with high sensitivity and specificity (100% and 60%) and positive and negative predictive values (PPV 80%, NPV 100%). PAPs, mean PAP, ACT and PAPd/TR confirmed their prevailing diagnostic ability (A-ROC from 0.74 to 0.86) in identifying pulmonary hypertension with fair to high feasibility (67% to 91%) and an odds ratio (OR) indicative of strong association. ACT and PAPd/TR, the 2 parameters with the highest feasibility, allowed us to identify 46 of 49 (94%) hypertensive cases. The same parameters did not perform well in identifying patients with increased vascular resistance, with A-ROC ranging from 0.55 to 0.69. Heterogeneity of effect, due to right ventricular function or tricuspid regurgitation degree, could not be demonstrated in the ability of the echo Doppler measurements to identify pulmonary hypertension.

CONCLUSIONS

ACT, PAPd/TR, PAPs and mean PAP have been shown to accurately classify patients with chronic heart failure with or without pulmonary hypertension. In particular, ACT and PAPd/TR alone allowed reliable and accurate definition of pulmonary hypertension in 94% of patients, regardless of right ventricular function or degree of tricuspid regurgitation. Non-invasive pulmonary pressure assessment by the referred method might be useful in the evaluation of heart transplant candidates.

Noninvasive measurement of systemic vascular resistance using Doppler echocardiography

BACKGROUND

Systemic vascular resistance (SVR) is an integral therapeutic component of patients with heart failure and shock. We hypothesized that the ratio of the peak mitral regurgitant velocity (MRV) (m/s) to left ventricular outflow time-velocity integral (TVI(LVOT)) (cm) by Doppler would provide a noninvasive correlate of SVR.

METHODS

SVR was correlated to MRV/TVI(LVOT) in 33 patients undergoing right heart catheterization. Receiver operating characteristic curves were generated to determine the best-balanced sensitivity and specificity to identify SVR > 14 Wood units (WU) and <10 WU.

RESULTS

MRV/TVI(LVOT) correlated well with SVR (r = 0.842, 95% confidence interval 0.7-0.92, P <.001, Y = 0.459 + 49.397*X). By receiver operating characteristics, MRV/TVI(LVOT) > 0.27 had a 70% sensitivity and a 77% specificity to identify SVR > 14 WU. MRV/TVI(LVOT) < 0.2 had a 92% sensitivity and a 88% specificity to identify SVR < 10 WU.

CONCLUSION

Doppler echocardiography provides a reliable noninvasive assessment of SVR.

Papel da ecodopplercardiografia na avaliação da hipertensão arterial pulmonar

A adequada avaliação dos níveis de pressão na artéria pulmonar é fundamental para o diagnóstico e manuseio de pacientes com hipertensão arterial pulmonar (HAP) de qualquer etiologia. A ecocardiografia é um método nãoinvasivo, de baixo custo e amplamente disponível, que permite a avaliação anatômica e funcional das cavidades cardíacas direitas e a estimativa das pressões em artéria pulmonar, apresentando boa correlação com dados hemodinâmicos obtidos pelo cateterismo cardíaco. O mais preciso e confiável método utilizado pela ecocardiografia para a estimativa das pressões em artéria pulmonar é baseado na medida da velocidade do fluxo regurgitante da valva tricúspide, embora elas possam também ser estimadas pelo fluxo regurgitante pulmonar ou pela análise do fluxo sistólico pulmonar. Quando a qualidade da imagem obtida pela abordagem transtorácica não permite a avaliação adequada da anatomia cardíaca, a ecocardiografia transesofágica torna-se procedimento extremamente útil para complementar essa avaliação, permitindo, por vezes, a detecção de seus possíveis mecanismos causais. A ecocardiografia pode ser utilizada não só para o diagnóstico da HAP, mas também para orientar a conduta terapêutica e para a avaliação prognóstica desses pacientes. Em casos de tromboembolismo pulmonar agudo, já foi demonstrado que a detecção de disfunção ventricular direita pela ecocardiografia é um dado importante na indicação de terapia trombolítica. Da mesma forma, o método tem seu valor estabelecido para monitorização da resposta terapêutica em pacientes com HAP primária, na avaliação prognóstica de pacientes com doença pulmonar obstrutiva crônica e no acompanhamento de pacientes submetidos a transplante pulmonar.

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 > or =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 < or =35%), with a tricuspid regurgitation grade > or =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.

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.

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 > or = 12 mm Hg, pulmonary vascular resistance > or = 3 Wood units or pulmonary vascular resistance index > or = 6 Wood units x 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.

Frequency of Doppler measurable pulmonary artery pressures

The current literature suggests that right-sided heart pressures can be obtained noninvasively in approximately 60% of patients. We hypothesized that with a focused echocardiographic Doppler examination, measurable tricuspid or pulmonary valve regurgitation suitable for measuring pressures could be obtained in a higher percentage of patients. The study group consisted of 200 consecutive patients undergoing echocardiographic and Doppler hemodynamic evaluation. All patients were first examined by an ultrasonographer instructed to attempt to record tricuspid and pulmonary regurgitant velocities. After this examination, a designated cardiologist performed a focused examination with the intent of improving the signal quality and increasing the number of measurable signals for evaluation. Tricuspid regurgitation of measurable quality was recorded in 147 (73.5%) of 200 patients by the ultrasonographer; this result was improved to 172 patients (86%) by the designated cardiologist. Pulmonary regurgitation was obtainable in 147 (95%) of 154 patients and was of measurable quality in 137 (89%). When results of tricuspid and pulmonary regurgitation were combined, a quantifiable signal was obtained in 194 (97%) of 200 consecutive unselected patients. This study demonstrates that a well-trained ultrasonographer or echocardiologist can obtain right-sided pressures in at least 95% of all unselected cardiovascular patients.

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.

Echocardiographic evaluation of isolated pulmonary valve disease in adolescents and adults

Congenital pulmonary valve disease is often not discovered until adolescence or adulthood. Transthoracic two-dimensional echocardiography can provide detailed information regarding right ventricular outflow anatomy, although images are often less satisfactory than those obtained in infants and children. The more recent addition of biplanar transesophageal echocardiography has enhanced our ability to image the right ventricular outflow tract, pulmonary valve, and pulmonary artery noninvasively. Pulsed and continuous-wave Doppler estimates of subvalvular and transvalvular gradients have proved to be accurate. Doppler color flow mapping has proved useful in determining the location and direction of stenotic and regurgitant flow. With no accepted standard for comparison, quantification of regurgitation remains problematic. In many cases, echocardiography has replaced catheterization and angiography in the evaluation and long-term follow-up of congenital pulmonary valve disease before and after intervention.

Reliability and accuracy of measurement of transductal gradient by Doppler ultrasound

Simultaneous continuous wave Doppler echocardiography, aortic and pulmonary artery pressure measurements were performed during cardiac catheterization in 46 patients with patent ductus arteriosus. Doppler-derived systolic, mean and diastolic transductal gradients correlated well with those measured by catheterization, respectively (r = 0.972, SEE = 6.8 mmHg; r = 0.965, SEE = 5.4 mmHg; r = 0.939, SEE = 6.2 mmHg), and there were clinically acceptable agreements between the two technical measurements. It is concluded that Doppler echocardiography is a reliable and accurate technique for noninvasive estimation of transductal gradients.