Pulmonary Hypertension Phenotype Can Be Identified in Heart Failure With Reduced Ejection Fraction Using Echocardiographic Assessment of Pulmonary Artery Pressure With Supportive Use of Pressure Reflection Variables.

BACKGROUND: Pulmonary hypertension (PH) is frequent in patients with heart failure and reduced ejection fraction (HFrEF) with 2 different phenotypes: isolated postcapillary PH (IpcPH) and, with the worst prognosis, combined pre- and postcapillary PH (CpcPH). The aims of the present echocardiography study were to investigate (1) the ability to identify PH phenotype in patients with HFrEF using the newly adopted definition of PH (mean pulmonary artery pressure >20 mm Hg) and (2) the relationship between PH phenotype and right ventricular (RV) function. METHODS: One hundred twenty-four patients with HFrEF consecutively referred for heart transplant or heart failure workup were included with echocardiography and right heart catheterization within 48 hours. We estimated systolic pulmonary artery pressure (sPAPDoppler) and used a method to detect increased pulmonary vascular resistance (>3 Wood units) based on predefined thresholds of 3 pressure reflection (PRefl) variables (the acceleration time in the RV outflow tract [RVOT], the interval between peak RVOT and peak tricuspid regurgitant velocity, and the RV pressure augmentation following peak RVOT velocity). RESULTS: Using receiver operator characteristic analysis in a derivation group (n = 62), we identified sPAPDoppler ≥35 mm Hg as a cutoff that in a test group (n = 62) increased the likelihood of PH 6.6-fold. The presence of sPAPDoppler >40 mm Hg and 2 or 3 positive PRefl variables increased the probability of CpcPH 6- to 8-fold. A 2-step approach with primarily assessment of sPAPDoppler and the supportive use of PRefl variables in patients with mild/moderate PH (sPAPDoppler 41-59 mm Hg) showed 76% observer agreement and a weighted kappa of 0.63. The steady-state (pulmonary vascular resistance) and pulsatile (compliance, elastance) vascular loading are increased in both IpcPH and CpcPH with a comparable degree of RV dysfunction. CONCLUSIONS: The PH phenotype can be identified in HFrEF using standard echocardiographic assessment of pulmonary artery pressure with supportive use of PRefl variables in patients with mild to moderate PH.

Importance of through-plane heart motion correction for the assessment of aortic regurgitation severity using phase contrast magnetic resonance imaging.

PURPOSE: To elucidate the influence of through-plane heart motion on the assessment of aortic regurgitation (AR) severity using phase contrast magnetic resonance imaging (PC-MRI). APPROACH: A patient cohort with chronic AR (n = 34) was examined with PC-MRI. The regurgitant volume (RVol) and fraction (RFrac) were extracted from the PC-MRI data before and after through-plane heart motion correction and was then used for assessment of AR severity. RESULTS: The flow volume errors were strongly correlated to aortic diameter (R = 0.80, p < 0.001) with median (IQR 25%;75%): 16 (14; 17) ml for diameter>40mm, compared with 9 (7; 10) ml for normal aortic size (p < 0.001). RVol and RFrac were underestimated (uncorrected:64 ± 37 ml and 39 ± 17%; corrected:76 ± 37 ml and 44 ± 15%; p < 0.001) and ~ 20% of the patients received lower severity grade without correction. CONCLUSION: Through-plane heart motion introduces relevant flow volume errors, especially in patients with aortic dilatation that may result in underestimation of the severity grade in patients with chronic AR.

Importance of complex blood flow in the assessment of aortic regurgitation severity using phase contrast magnetic resonance imaging.

This study aimed to investigate if and how complex flow influences the assessment of aortic regurgitation (AR) using phase contrast MRI in patients with chronic AR. Patients with moderate (n = 15) and severe (n = 28) chronic AR were categorized into non-complex flow (NCF) or complex flow (CF) based on the presence of systolic backward flow volume. Phase contrast MRI was performed repeatedly at the level of the sinotubular junction (Ao1) and 1 cm distal to the sinotubular junction (Ao2). All AR patients were assessed to have non-severe AR or severe AR (cut-off values: regurgitation volume (RVol) ≥ 60 ml and regurgitation fraction (RF) ≥ 50%) in both measurement positions. The repeatability was significantly lower, i.e. variation was larger, for patients with CF than for NCF (≥ 12 ± 12% versus ≥ 6 ± 4%, P ≤ 0.03). For patients with CF, the repeatability was significantly lower at Ao2 compared to Ao1 (≥ 21 ± 20% versus ≥ 12 ± 12%, P ≤ 0.02), as well as the assessment of regurgitation (RVol: 42 ± 34 ml versus 54 ± 42 ml, P < 0.001; RF: 30 ± 18% versus 34 ± 16%, P = 0.01). This was not the case for patients with NCF. The frequency of patients that changed in AR grade from severe to non-severe when the position of the measurement changed from Ao1 to Ao2 was higher for patients with CF compared to NCF (RVol: 5/26 (19%) versus 1/17 (6%), P = 0.2; RF: 4/26 (15%) versus 0/17 (0%), P = 0.09). Our study shows that complex flow influences the quantification of chronic AR, which can lead to underestimation of AR severity when using PC-MRI.

Echocardiographic assessment at rest and during stress in patients with intermittent claudication.

Objective. Skeletal muscle perfusion during walking relies on complex interactions between cardiac activity and vascular control mechanisms, why cardiac dysfunction may contribute to intermittent claudication (IC) symptoms. The study aims were to describe cardiac function at rest and during stress in consecutive IC patients, to explore the relations between cardiac function parameters and treadmill performance, and to test the hypothesis that clinically silent myocardial ischemia during stress may contribute to IC limb symptomatology. Design. Patients with mild to severe IC (n = 111, mean age 67 y, 52% females, mean treadmill distance 195 m) underwent standard echocardiography, dobutamine stress echocardiography (SE) and treadmill testing. The patient cohort was separated in two groups based on treadmill performance (HIGH and LOW performance). Results. Ten patients (9%) had regional wall motion abnormalities of which three had left ventricular ejection fraction <50% at standard echocardiography. A majority had lower than expected systolic- and diastolic ventricular volumes. LOW performers had smaller diastolic left ventricular volumes and lower global peak systolic velocity during dobutamine stress. No patient demonstrated significant cardiac dysfunction during dobutamine provocation that was not also evident at standard echocardiography. Conclusions. Most IC patients were without signs of ischemic heart disease or cardiac failure. The majority had small left ventricular volumes. The hypothesis that clinically silent myocardial ischemia impairing left ventricular function during stress may contribute to IC limb symptomatology was not supported.

Doppler echocardiography can provide a comprehensive assessment of right ventricular afterload.

BACKGROUND: The purpose of this study was to evaluate novel Doppler echocardiographic methods for a comprehensive assessment of right ventricular afterload, including pulmonary artery (PA) mean pressure (PAMP) and the PA pressure waveform. METHODS: The study comprised 109 patients who underwent right-heart catheterization simultaneously (group A, n = 31) with Doppler echocardiography on 35 occasions or nonsimultaneously (group B, n = 78) within 24 hours of Doppler echocardiography. Right ventricular afterload variables were obtained using pulsed Doppler in the PA and continuous Doppler of tricuspid regurgitation. The intervals from QRS to the opening and closing of the pulmonary valve and to the peak velocity of tricuspid regurgitation were measured. PA end-diastolic pressure, PA systolic pressure, and PA notch pressure were calculated. The Doppler-derived pressure curve was separated into 3 parts with fitted second-order curves. RESULTS: Catheter PAMP and Doppler PA systolic pressure in group A were strongly related (R = 0.85). The regression equation from group A (PAMP = 0.65 x Doppler PA systolic pressure - 1.2 mm Hg) was used to calculate PAMP in group B. There was no difference between catheter PAMP (mean, 39 +/- 18 mm Hg; range, 8-95 mm Hg) and Doppler PAMP (mean, 39 +/- 15 mm Hg; range, 12-83 mm Hg) (P = .85). The systolic areas under the curves for catheter and Doppler PAMP in group A were 20 +/- 4.7 and 20 +/- 4.0 mm Hg s, respectively (P = .52), and the diastolic areas were 21 +/- 5.7 and 22 +/- 6.3 mm Hg s, respectively (P = .21). CONCLUSION: A comprehensive assessment of right ventricular afterload that includes PAMP and the PA pressure waveform can be provided by Doppler echocardiography in patients with a wide range of PA pressures and different diagnoses.

Assessment of pulmonary vascular resistance by Doppler echocardiography in patients with pulmonary arterial hypertension.

BACKGROUND: Assessment of pulmonary artery pressures, cardiac output (CO) and pulmonary vascular resistance (PVR) is crucial in the management of patients with pulmonary arterial hypertension (PAH). The aim of the present study was to investigate whether Doppler echocardiography can be used to determine PVR in patients with PAH. METHODS: Forty-two patients were included and Doppler echocardiography was performed simultaneously (n = 22) and non-simultaneously (n = 60) with right heart catheterization. The tricuspid regurgitation velocity was used to estimate pulmonary arterial peak systolic and diastolic (PADP) pressures (Bernoulli equation). At the time of pulmonary valve opening, right ventricular pressure equals PADP. The tricuspid regurgitation velocity at the time of pulmonary valve opening was measured by superimposing the time from the QRS to the onset of pulmonary flow on the tricuspid regurgitation velocity envelope. Pulmonary capillary wedge pressure, right atrial pressure and CO were assessed using standard Doppler echocardiography methods. Right heart catheterization was performed using Swan-Ganz catheters and thermodilution for CO determination. RESULTS: The differences (mean +/- SD) between catheter and simultaneous/non-simultaneous Doppler echocardiography were 0.3 +/- 0.8 (p = 0.10)/-0.3 +/- 1.1 (p = 0.06) liter/min for CO, 2.9 +/- 5.1 (p = 0.02)/-1.2 +/- 7.4 (p = 0.2) mm Hg for the transpulmonary gradient (TPG) and 0.3 +/- 2.1 (p = 0.65)/0.8 +/- 2.4 (p = 0.02) Wood unit for PVR. The correlation coefficients between catheter and simultaneous/non-simultaneous Doppler echocardiography were 0.86/0.75 for CO, 0.92/0.90 for TPG and 0.93/0.92 for PVR. CONCLUSIONS: A comprehensive hemodynamic assessment that includes CO, TPG and PVR can be provided by Doppler echocardiography in patients with severe pulmonary hypertension.

The E/e filling index and right ventricular pressure in relation to applied international Doppler recommendations of left ventricular filling assessment.

AIM: A ratio>15 between the early diastolic pulsed Doppler velocities of the mitral inflow (E) and the basal left ventricular (LV) tissue (e) has been demonstrated to predict an elevated LV filling pressure (FP). An elevated LVFP implies an elevated right ventricular pressure (RVp). In order to investigate the sensitivity of the E/e filling index, we compared E/e and RVp, in their ability to identify a Doppler-assumed elevation of LVFP. METHODS AND RESULTS: Application of pulsed Doppler international recommendations grouped 134 patients with acute coronary syndromes (ACS) and 50 age- and sex-matched controls, according to LV filling: normal; delayed relaxation; an isolated pathological mitral-pulmonary venous-A-wave-duration difference; pseudo normal; or a restrictive filling pattern. An E/e>15 and an RVp>30 mmHg showed the following (%) sensitivity (32/94), specificity (95/76), positive (68/59), and negative (80/97) predictive values of a Doppler-assumed elevation of LVFP, in terms of either a pseudo normal or a restrictive filling pattern. CONCLUSION: The low sensitivity of E/e to detect a Doppler-assumed elevation of LVFP could limit its clinical usefulness as a single variable, in ACS. The high sensitivity and negative predictive value of RVp support its use as an additional LV filling variable in these patients.

Improved stroke volume assessment in the aortic and mitral valves with a new method in subjects without regurgitation.

BACKGROUND: Echocardiography combining Doppler and two-dimensional data is recommended for quantitative assessments of valvular regurgitation. We applied a new method to calculate the mitral annulus (MA) area in combination with multiple sample sites. Individuals without regurgitation in whom the valvular and left ventricular stroke volumes (SV) should be identical were investigated in order to evaluate the feasibility in quantitative assessments of valvular regurgitation. METHODS AND RESULTS: Twenty subjects were included. Flow velocity was registered with pulsed Doppler in different positions in the left ventricular outflow tract (LVOT) and in the MA. The MA area was assumed to be either circular, using the diameter from a four-chamber projection, or elliptic, using the major diameter from a parasternal short axis and a minor diameter from an apical long axis. Left ventricular (LV) SV was measured from LV volumes using the biplane method. The overall difference between LVOT SV and mitral SV using one centrally located measurement and elliptic MA was 3.2+/-15.6 ml (P=0.38), 0.9+/-15.7 ml between LVOT SV and LV SV (P=0.80) and -2.2+/-15.2 ml between mitral SV and LV SV (P=0.54). The corresponding standard deviation of the differences as a percentage of the mean value was 24%, 25% and 23%. A circular shaped MA overestimated the mitral SV compared with LVOT SV (P=0.009) and LV SV (P=0.004). Increasing the number of sample sites in the LVOT or MA did not further improve the results. CONCLUSION: Doppler and two-dimensional echocardiography can be used to quantify regurgitation in groups of patients. In individual patients the wide distribution of differences between valves and LV SV implies that the method should be used in conjunction with other Doppler echocardiographic parameters.

Echocardiographic assessment of anatomic lesions predicts surgical strategy in mitral regurgitation.

OBJECTIVE: In the present study, we evaluate our ability to predict surgical procedure repair or replacement using preoperative echocardiography. DESIGN: The reports from transthoracic echocardiographic examinations of 298 patients were analyzed and the gross anatomic lesions and the mechanisms involved were classified into one of three main groups (functional with normal valves, organic degenerated with hypermobile valve or organic degenerated without hypermobility). RESULTS: It was possible to assess the likelihood of repair in 226 patients (76%). The criteria used were institution based and reflect the surgical procedures during the study period (1995-1999). The proportion of patients undergoing repair was 58%. In patients with a high likelihood, repair was performed in 86%. The corresponding figures in the intermediate- and low-likelihood groups were 63 and 23%, respectively. Hypermobility in the posterior leaflet and functional mitral regurgitation led to repair in the majority of patients, while patients with hypermobility in the anterior or both valves more frequently underwent replacement. CONCLUSION: We conclude that it is possible to identify patients with a high likelihood of repair using transthoracic echocardiography.