Parameters Of Right Ventricular Performance Research Articles

Blood flow kinetic energy is a novel marker for right ventricular global systolic function in patients with left ventricular assist device therapy.

Right ventricular (RV) failure remains a major concern in heart failure (HF) patients undergoing left ventricular assist device (LVAD) implantation. We aimed to measure the kinetic energy of blood in the RV outflow tract (KE-RVOT) - a new marker of RV global systolic function. We also aimed to assess the relationship of KE-RVOT to other echocardiographic parameters in all subjects and assess the relationship of KE-RVOT to hemodynamic parameters of RV performance in HF patients. Fifty-one subjects were prospectively enrolled into 4 groups (healthy controls, NYHA Class II, NYHA Class IV, LVAD patients) as follows: 11 healthy controls, 32 HF patients (8 NYHA Class II and 24 Class IV), and 8 patients with preexisting LVADs. The 24 Class IV HF patients included 21 pre-LVAD and 3 pre-transplant patients. Echocardiographic parameters of RV function (TAPSE, St', Et', IVA, MPI) and RV outflow color-Doppler images were recorded in all patients. Invasive hemodynamic parameters of RV function were collected in all Class IV HF patients. KE-RVOT was derived from color-Doppler imaging using a vector flow mapping proprietary software. Kruskal-Wallis test was performed for comparison of KE-RVOT in each group. Correlation between KE-RVOT and echocardiographic/hemodynamic parameters was assessed by linear regression analysis. Receiver operating characteristic curves for the ability of KE-RVOT to predict early phase RV failure were generated. KE-RVOT (median ± IQR) was higher in healthy controls (55.10 [39.70 to 76.43] mW/m) than in the Class II HF group (22.23 [15.41 to 35.58] mW/m, p < 0.005). KE-RVOT was further reduced in the Class IV HF group (9.02 [5.33 to 11.94] mW/m, p < 0.05). KE-RVOT was lower in the LVAD group (25.03 [9.88 to 38.98] mW/m) than the healthy controls group (p < 0.005). KE-RVOT had significant correlation with all echocardiographic parameters and no correlation with invasive hemodynamic parameters. RV failure occurred in 12 patients who underwent LVAD implantation in the Class IV HF group (1 patient was not eligible due to death immediately after the LVAD implantation). KE-RVOT cut-off value for prediction of RV failure was 9.15 mW/m (sensitivity: 0.67, specificity: 0.75, AUC: 0.66). KE-RVOT, a novel noninvasive measure of RV function, strongly correlates with well-established echocardiographic markers of RV performance. KE-RVOT is the energy generated by RV wall contraction. Therefore, KE-RVOT may reflect global RV function. The utility of KE-RVOT in prediction of RV failure post LVAD implantation requires further study.

Comprehensive Echocardiographic Assessment of Ventricular Function and Pulmonary Pressure in the Neonatal Omphalocele Population.

Pulmonary hypertension (PH) has been described in the neonatal omphalocele population. This study was aimed to describe cardiac function and PH severity using echocardiography in newborns with giant omphalocele (GO) and with non-GO and determine if right ventricular (RV) dysfunction is associated with mortality. Retrospective, single-center analysis of first echocardiography among neonatal omphalocele patients born between 2004 and 2017 was conducted. Multivariate logistic and univariate Cox's regression was constructed to measure hazard ratio (HR) for death outcome. There were 32 newborns, of whom 18 were GO and 7 died. GO had increased systolic pulmonary arterial to systolic systemic blood pressure ratio (97% [isosystemic] vs. 73% [three-fourths systemic] p = 0.03). RV performance parameters (tricuspid annular plane excursion, HR = 0.40; fractional area change, HR = 0.90; and RV peak global longitudinal strain, HR = 1.39) were associated with mortality. These RV performance parameters remained associated in a multiple logistic regression accounting for gestational age and GO status. The overall population had abnormal eccentricity index and pulmonary artery acceleration time to RV ejection time ratio, two markers of PH. Patients with omphalocele have increased pulmonary pressure, with GO being worse than non-GO. RV dysfunction at initial echocardiography was significantly associated with mortality.

Blood Flow Kinetic Energy of Right Ventricular Outflow Tract: A Marker for Right Ventricular Global Systolic Function

Purpose Right ventricular (RV) failure remains a major concern in heart failure (HF) patients undergoing LVAD surgery. We aimed to measure flow kinetic energy (KE) of the RV outflow tract (OT) - a new marker of RV global systolic function - and assess its relationship to well-established echocardiographic and hemodynamic parameters of RV performance in heart failure (HF) and LVAD pts. Methods Twenty-one subjects were prospectively enrolled: 12 HF pts (2 NYHA Class II and 10 Class IV), 3 HeartMate II (HMII) and 6 healthy controls (C). Echocardiographic parameters of RV function (TAPSE, St’, Et’, IVA, MPI) and RV inflow-outflow color Doppler images were recorded on all pts. Invasive hemodynamic parameters of RV function and RV failure risk score (RVFRS) were collected in all Class IV pts. KE-RVOT was derived from color Doppler images using a vector flow mapping proprietary software, Echo VFM® (Cardio Flow Design, Tokyo, Japan) (Figure). Kruskal-Wallis test was performed for comparison of each group. Correlation between KE-RVOT and echocardiographic/hemodynamic parameters as well as RVFRS was assessed by linear regression analysis. Results KERVOT (Median ± IQR) was higher in C (56.98 [37.63 to 97.21] mW/m) than in Class II HF (26.60 [26.14 to 27.05] mW/m, p<0.05) and further declined in Class IV HF (7.45 [4.87 to 10.46] mW/m, p<0.05)). LVAD therapy partially restored KE-RVOT (23.17 [9.77 to 25.03] mW/m, p<0.05)) to levels similar to Class II HF (Figure). KE-RVOT was significantly related to TAPSE, St’, CVP/PCWP, and PAPi (r = 0.5887, 0.6671, -0.6942, and 0.7899, respectively, all p<0.05) but not to RVFRS. Conclusion KE-RVOT, a novel noninvasive measure of RV function, strongly correlates with well-established markers of RV performance. The utility of KE-RVOT in prediction of RV failure post LVAD requires further study. Right ventricular (RV) failure remains a major concern in heart failure (HF) patients undergoing LVAD surgery. We aimed to measure flow kinetic energy (KE) of the RV outflow tract (OT) - a new marker of RV global systolic function - and assess its relationship to well-established echocardiographic and hemodynamic parameters of RV performance in heart failure (HF) and LVAD pts. Twenty-one subjects were prospectively enrolled: 12 HF pts (2 NYHA Class II and 10 Class IV), 3 HeartMate II (HMII) and 6 healthy controls (C). Echocardiographic parameters of RV function (TAPSE, St’, Et’, IVA, MPI) and RV inflow-outflow color Doppler images were recorded on all pts. Invasive hemodynamic parameters of RV function and RV failure risk score (RVFRS) were collected in all Class IV pts. KE-RVOT was derived from color Doppler images using a vector flow mapping proprietary software, Echo VFM® (Cardio Flow Design, Tokyo, Japan) (Figure). Kruskal-Wallis test was performed for comparison of each group. Correlation between KE-RVOT and echocardiographic/hemodynamic parameters as well as RVFRS was assessed by linear regression analysis. KERVOT (Median ± IQR) was higher in C (56.98 [37.63 to 97.21] mW/m) than in Class II HF (26.60 [26.14 to 27.05] mW/m, p<0.05) and further declined in Class IV HF (7.45 [4.87 to 10.46] mW/m, p<0.05)). LVAD therapy partially restored KE-RVOT (23.17 [9.77 to 25.03] mW/m, p<0.05)) to levels similar to Class II HF (Figure). KE-RVOT was significantly related to TAPSE, St’, CVP/PCWP, and PAPi (r = 0.5887, 0.6671, -0.6942, and 0.7899, respectively, all p<0.05) but not to RVFRS. KE-RVOT, a novel noninvasive measure of RV function, strongly correlates with well-established markers of RV performance. The utility of KE-RVOT in prediction of RV failure post LVAD requires further study.

Decreased biventricular longitudinal strain shortly after congenital heart defect surgery.

Impaired ventricular performance in patients who underwent surgery for congenital heart defect (CHD) may ultimately result in clinical heart failure. It is therefore important to regularly evaluate the left ventricular (LV) and right ventricular (RV) performance. We evaluated tissue Doppler imaging (TDI) and speckle tracking echocardiography (STE) before and after surgical correction of a CHD. Patients with CHD undergoing biventricular corrective surgery were included in this retrospective study. In addition, a group of healthy controls was included. The performance of LV, RV and interventricular septum (IVS) was assessed using mitral inflow velocities, TDI peak systolic (S'), peak early (E') and peak late (A') diastolic velocity. LV and RV global longitudinal strain (GLS) were assessed using STE. Measurements were performed preoperatively and at discharge. A total of 204 patients and 78 controls were included. All TDI measurements were significantly decreased after surgery. Nonetheless, LV S' and A' were still within normal limits. LV and RV GLS were significantly reduced after surgery and significantly lower compared to controls. A longer aortic cross-clamp time and cardiopulmonary bypass (CPB) time were associated with significantly lower TDI and strain parameters in the RV and IVS, but not in the LV. TDI and STE results generally imply a significantly lower ventricular performance in patients with CHD postoperatively. Furthermore, a negative correlation was observed between aortic cross-clamping and CPB time and several RV performance parameters. As this association was not observed in the LV, this could implicate less vulnerability of the LV to cardiopulmonary bypass.

Abstract 12121: Right Ventricular Free-Wall Longitudinal Speckle-Tracking Strain in Patients With Pulmonary Arterial Hypertension Under Specific Treatment

Introduction: Pulmonary arterial hypertension (PAH) is a devastating disease of pulmonary vascular remodelling, right heart failure and limited survival. Although right ventricular (RV) dysfunction is a major determinant of outcome in patients with PAH, the optimal measure of RV function is poorly defined. Hypothesis: The objectives of this study were to test the utility of RV free wall speckle-tracking strain (RV-free) as an assessment tool for RV function in patients with PAH who are already under specific medical treatment compared with conventional echocardiographic parameters and to investigate the relationship of the findings obtained with RV-free with hemodynamic parameters of RV performance. Methods: Prospective RV- free measurement was performed on 92 PAH patients of different etiologies (49 PAH associated with congenital heart disease, 21 idiopathic PAH, 11 PAH associated with connective tissue disease and 11 chronic thromboembolic pulmonary hypertension) who were on PAH spesific treatment for at least 3 months. RV-free was calculated by averaging each of 3 regional peak systolic strain values. The mean follow-up was 222±133 days. Conventional echocardiographic parameters-RV FAC, TAPSE and Tricuspid S-, hemodynamic parameters -functional class, 6-min. walking distance, and NT-proBNP- were also studied. Results: The mean age was 41± 16 years and 67.4% were female. Mean RV- free of the study population was %-13.16 ± 6.3. There was a significant positive correlation between RV-free and functional class (r=0.312, p=0.01), NT-proBNP (r=0.423, p=0.0001), whereas negative correlation with FAC (r=-0.637, p=0.0001), TAPSE (r=-0.524, p=0.0001), Tricuspid S (r=-0.450, p=0.0001), 6-min. walking distance (r=-0.333, p=0.002). RV-free significantly correlated with all follow-up adverse events, death and clinical right heart failure (p=0.04, p=0.03, p=0.02, respectively). According to the ROC analysis, the cut-off value for the development of clinical right heart failure was -13.8% (sensitivity: 71%, specificity: 60%) for RV-free. Conclusions: Assessment of RV-free is a feasible, easy to perform method and maybe used as a predictor of right heart failure, clinical deterioration and mortality in patients under PAH specific treatment.

Cardiac MRI assessment of right ventricular function: impact of right bundle branch block on the evaluation of cardiac performance parameters.

Right ventricular (RV) function represents a prognostic marker in patients with corrected congenital heart disease. In up to 80 % of these patients, right branch bundle block (RBBB) exists and leads to asynchronous ventricular contraction. The aim of this retrospective study was to evaluate the change of RV performance parameters considering delayed RV end-systolic contraction. RV volumes of 33 patients were assessed twice: 1) not taking account of RBBB (group I), and 2) considering RBBB (group II). According to the RV ejection fraction (EF) for both groups, RV function was classified in different categories (>50 % = normal, 40-50 % = mildly-, 30-40 % = moderately-, <30 % = severely-reduced). The mean time difference between maximal systolic contraction of the septum and RV free wall was 90.7 ms ± 42.6. Consequently, RV end-systolic volume was significantly decreased in group II (p < 0.001). Accordingly, RV stroke volume and RV EF were significantly higher in group II (p < 0.001). There was also a significant change in the assessment of RV function (p < 0.02). RBBB induced delayed RV contraction can be detected at CMR. Ignoring the RV physiology in RBBB patients leads to a statistically significant underscoring of RV performance parameters. • Right branch bundle block leads to an asynchronous ventricular contraction • In CMR, a delayed right ventricular contraction due to RBBB can be detected • Ignoring RV physiology in RBBB patients leads to underscoring of RV performance.

Abstract 14798: Right Atrial Function as Prognostic factor in Patients with Pulmonary Hypertension

Background: The development of right ventricular (RV) dysfunction in patients with pulmonary hypertension (PH) has been associated with adverse outcomes. Right atrial (RA) function could be a prognostic factors as well as RV function, but non-invasive evaluation of RA function is limited. Our objective was thus to test the hypothesis that RA function was associated with hemodynamic parameters of RV performance in PH patients. Methods: Eighty PH patients with mean pulmonary artery pressure (PAP) of 40±11mmHg (all≥25mmHg) were recruited in this study. RA function was assessed by using two-dimensional speckle-tracking strain from RV-focused apical 4-chamber view. RA strain was calculated with the reference point set at the P wave, which enabled the recognition of peak negative (RAneg), positive strain (RAposi), and the sum of those values (RAtotal), corresponding to RA contractile, conduit, and reservoir function, respectively. All patients underwent right-heart catheterization for measurement of mean PAP and pulmonary vascular resistance (PVR). Results: RAneg (r=0.24 and p=0.03), RAposi (r=0.31 and p=0.01) and RAtotal (r=0.35 and p=0.001) were significantly correlated with mean PAP. In addition, RAposi (r=0.41 and p&lt;0.001) and RAtotal (r=0.44 and p&lt;0.001) were also correlated with PVR. Conclusions: Non-invasively assessed RA strains were associated with mean PAP and PVR. RA strain may be of a valuable additive factor for the management of PH patients, and thus have potential clinical applications.

Abstract 12967: Efficacy of Combining Assessment of Right Ventricular Function and Right Atrial Remodeling as Prognostic Factor in Patients With Pulmonary Hypertension

Background: Since survival of patients with pulmonary hypertension (PH) is closely related to right ventricular (RV) function, assessment of RV function is important for patients with PH. Right atrial (RA) area and/or RA pressure have also been reported to serve as prognostic predictors for adverse outcomes for in PH patient. Accordingly, we tested the hypothesis that the addition of RA remodeling to RV function enhances the capability of the latter to predict long-term outcome for PH patients. Methods: We studied 82 PH patients, all of whom underwent echocardiography and right heart catheterization. RV function was calculated by averaging the three regional peak speckle-tracking longitudinal strains from RV free wall (RV-free). RA remodeling was assessed as the RA area traced planimetrically at end-systole. Pre-defined cutoffs for RV dysfunction and RA remodeling were RV-free≤19.4% and RA area of &gt;18cm2, respectively. Long-term unfavorable outcome events were tracked for 2.0 years. Results: RA area correlated with mean RA pressure (r=0.62, p&lt;0.001), as well as with tricuspid E/E’ (r=0.38, p=0.001). However, RA area with RV restrictive filling was significantly larger than with others (all p&lt;0.05). Kaplan-Meier analysis revealed that patients with RV-free ≤19.4% had worse long-term outcomes than those with RV-free &gt;19.4% (log-rank p=0.01), as did patients with RA area&gt;18cm2 compared with those with RA area ≤18cm2 (log-rank p&lt;0.05). For sequential Cox models, a model based on hemodynamic parameters of RV performance (χ2 =3.11) was improved by addition of brain natriuretic peptide, World Health Organization functional class (χ2 =9.24; p&lt;0.05), and RV-free (χ2 =17.11; p=0.005), and further improved by addition of RA area (χ2 =21.36, p&lt;0.05). Conclusions: The combined assessment of RV function and RA remodeling results in more accurate prediction of long-term outcome, and may well have clinical implications for better management of PH patients.

Utility of combining assessment of right ventricular function and right atrial remodeling as a prognostic factor for patients with pulmonary hypertension.

We tested the hypothesis that the addition of right atrial (RA) remodeling to right ventricular (RV) function enhances the capability of the latter to predict long-term outcome for pulmonary hypertension (PH) patients. We studied 82 PH patients, all of whom underwent echocardiography and right heart catheterization. RV function was calculated by averaging the three regional peak speckle-tracking longitudinal strains from RV free wall (RV-free). RA remodeling was assessed as the RA area traced planimetrically at end-systole. Pre-defined cutoffs for RV dysfunction and RA remodeling were RV-free ≤19.4 % and RA area of >18 cm(2), respectively. Long-term unfavorable outcome events were tracked for 2.0 years. RA area correlated with mean RA pressure (r = 0.62, p < 0.001), as well as with tricuspid E/E' (r = 0.38, p = 0.001). Moreover, RA area in patients with RV restrictive filling was significantly larger than that in patients with others (all p < 0.05). Kaplan-Meier analysis revealed that patients with RV-free ≤19.4 % had worse long-term outcomes than those with RV-free >19.4 % (log-rank p = 0.01), as did patients with RA area >18 cm(2) compared with those with RA area ≤18 cm(2) (log-rank p < 0.05). For sequential Cox models, a model based on hemodynamic parameters of RV performance (χ2 = 3.11) was improved by addition of brain natriuretic peptide, World Health Organization functional class (χ2 = 9.24; p < 0.05), and RV-free (χ2 = 17.11; p = 0.005), and further improved by addition of RA area (χ2 = 21.36, p < 0.05). In conclusion, the combined assessment of RV function and RA area results in more accurate prediction of long-term outcome, and may well have clinical implications for better management of PH patients.

Utility of Right Ventricular Free Wall Speckle-Tracking Strain for Evaluation of Right Ventricular Performance in Patients with Pulmonary Hypertension

The objectives of this study were to test the utility of right ventricular (RV) speckle-tracking strain as an assessment tool for RV function in patients with pulmonary hypertension (PH) compared with conventional echocardiographic parameters and to investigate the relationship of the findings obtained with RV speckle-tracking strain with the hemodynamic parameters of RV performance. Forty-five prospective consecutive patients with PH were studied. RV free wall longitudinal speckle-tracking strain (RV-free) and RV septal wall longitudinal speckle-tracking strain (RV-septal) were calculated by averaging each of three regional peak systolic strains along the entire right ventricle. The conventional echocardiographic parameters-RV fractional area change, RV myocardial performance index, tricuspid annular plane systolic excursion, and tricuspid annular peak systolic velocity-were also studied. For comparison, 22 age-matched volunteers with normal ejection fractions were studied. RV-free in patients with PH was significantly lower than that in normal controls, but RV-septal in the two groups was similar. Importantly, multivariate analysis revealed that RV-free was an independent echocardiographic predictor of hemodynamic RV performance items, including mean pulmonary artery pressure (β=-0.844, P= .001) and pulmonary vascular resistance (β= -0.045, P < .001). RV-free was also correlated with RV ejection fraction and RV end-systolic volume measured by cardiac magnetic resonance imaging and with 6-min walking distance (r= 0.60, r= 0.56, and r= 0.49, respectively, P < .05). Furthermore, the improvement in RV-free 5 ± 3 months after adding medical treatment was significantly correlated with that in 6-min walking distance (r= 0.68, P < .0001). RV-free has the potential to allow for noninvasive follow-up of patients with PH.

The Effect of Chronic Pulmonary Hypertension on Diastolic Annular Tissue Velocities: A Pilot Study

Tissue Doppler imaging (TDI) of mitral (MA) and tricuspid annular (TA) events has been shown to describe systolic and diastolic properties of each respective ventricle. However, the effect of chronic elevations in pulmonary artery systolic pressure (PASP) on individual diastolic annular velocities has not been well characterized. Measurements of left (LV) and right ventricular (RV) performance and TDI of the lateral MA and TA to measure systolic and early and late diastolic velocities were recorded from 50 individuals (group I: mean age was 56 ± 15 years and mean PASP of 29 ± 6 mm Hg) and from 50 patients (group II: mean age was 55 ± 14 years and mean PASP of 83 ± 27 mm Hg). Group II patients had worse parameters of RV performance whereas LV systolic function remained unaffected when compared with group I. Group II had lower TA early velocities (0.09 ± 0.04 m/sec versus 0.12 ± 0.03 m/sec; P < 0.0001) with higher late diastolic MA velocities (0.12 ± 0.04 m/sec versus 0.10 ± 0.03 m/sec; P < 0.002) than group I. MA late diastolic velocity (P < 0.02) was the most useful in identifying elevated PASP and early diastolic TA velocity (P < 0.01) in identifying abnormal right ventricular fractional area change. Chronic pulmonary hypertension seems to selectively affect TDI annular diastolic velocities of both ventricles in different ways. Additional studies are needed to correlate changes in annular TDI velocities with symptoms and clinical outcomes in chronic pulmonary hypertension.

Right ventricular function in myocardial infarction complicated by cardiogenic shock: Improvement with levosimendan*

Levosimendan improves left ventricular hemodynamic function in patients with cardiogenic shock. However, its impact on right ventricular performance has not been determined. We compared the hemodynamic effects of levosimendan on left and right ventricular function in patients with intractable cardiogenic shock following myocardial infarction. Observational hemodynamic study. Tertiary care center university hospital. Fifty-six patients with cardiogenic shock secondary to myocardial infarction were treated with percutaneous revascularization (including intra-aortic balloon pump when appropriate) and commenced on conventional inotropic therapy. Twenty-five consecutive patients with cardiogenic shock due to myocardial infarction who had not improved sufficiently with conventional therapy (including dobutamine and norepinephrine) received levosimendan (as a bolus of 12 microg/kg per minute for 10 mins then 0.1 microg/kg per minute--0.2 mug/kg per minute) as "bail-out" therapy for 24 hrs while invasive hemodynamic parameters were recorded. Levosimendan therapy was associated with a significant increase in cardiac index from 2.1 +/- 0.1 to 3.0 +/- 0.2 L x min x m (p < .01). In addition, levosimendan enhanced right ventricular cardiac power index (0.14 +/- 0.19 to 0.18W +/- 0.12, p < .001), while pulmonary vascular resistance fell from 227.7 +/- 94.5 to 178.1 +/- 62.3 dyne x s x cm (p = .002). No significant change in central venous pressure or mean pulmonary artery pressure was observed. The observed hemodynamic improvement was sustained after the levosimendan infusion was stopped. Levosimendan infusion for cardiogenic shock following acute myocardial infarction improved hemodynamic parameters of right ventricular performance. Furthermore, we describe the use of right ventricular cardiac power index as a hemodynamic parameter of right ventricular performance.

Relation of Right Ventricular Free Wall Mechanical Delay to Right Ventricular Dysfunction as Determined by Tissue Doppler Imaging

Several well-established echocardiographic parameters used in the assessment of right ventricular (RV) performance, as well as tissue Doppler imaging (TDI) to investigate RV free wall mechanical events, were prospectively obtained from a heterogenous group of 20 patients with varying degrees of pulmonary hypertension (mean age 51 +/- 13 years; World Health Organization class average 2.8, mean pulmonary systolic pressure 78 +/- 24 mm Hg) and compared with similar data retrospectively obtained from 20 healthy volunteers (mean age 45 +/- 15 years). Patients with varying degrees of pulmonary hypertension had worse RV performance parameters than healthy volunteers (RV fractional area change 37 +/- 13% vs 52 +/- 5%, p < 0.0001; RV myocardial performance index 0.76 +/- 0.31 vs 0.29 +/- 0.11, p < 0.0001; and eccentricity index 1.41 +/- 0.57 vs 0.98 +/- 0.06, p < 0.005). Similarly, in these patients with abnormal RV performance, TDI showed statistically significant smaller peak longitudinal RV free wall strain (-21.5 +/- 9.0% vs -28.0 +/- 4.1%, p < 0.01) and significantly delayed time to peak strain (459 +/- 76 vs 388 +/- 29 ms, p < 0.0005) values than in healthy volunteers; a very strong correlation between RV mechanical delay and RV fractional area change (r = -0.89) was noted.

Assessment of the Response of Right Ventricular Performance to Decreasing Levels of Mechanical Assistance by On-Line

The rapid assessment of the response of right ventricular (RV) performance to decreasing levels of mechanical assistance may be an important adjunct in determining if a patient can tolerate the removal of such a device. This report describes the use of on-line pressure area relationships to assess RV function in a patient supported with an RV assist device (RVAD). Mid RV short axis cross-sectional area was measured on-line by transesophageal echocardiography with an automated endocardial border detection feature. RV pressure was measured with a high fidelity catheter. Pressure and area were plotted simultaneously on a computer workstation interfaced with the pressure and echo systems to yield on-line pressure area loops. The following indices of RV performance were calculated while RVAD flow was decreased in 1 L/min increments: stroke work' (SW′ = ∫PdA)[mmHg*cm2], stroke area (SA = Maximum Area-Minimum Area)[cm2], and fractional area change (FAC = SA/Maximum Area*100)[%]. SW', SA, and FAC significantly increased with decreasing RVAD flow: SW'(from 32 to 61 mmHg*cm2), SA (from 2.58 to 4.37 cm2), and FAC (from 20 to 32%). In conclusion, the increase in these parameters of RV performance with decreasing mechanical assistance suggested that this patient would tolerate removal of the RVAD, which was subsequently successful. This method of on-line pressure area relationships may be useful to predict the need for further mechanical assistance.ASAIO Journal1994; 40:1032-1035.

Assessment of the Response of Right Ventricular Performance to Decreasing Levels of Mechanical Assistance by On-Line Pressure Area Relationships

The rapid assessment of the response of right ventricular (RV) performance to decreasing levels of mechanical assistance may be an important adjunct in determining if a patient can tolerate the removal of such a device. This report describes the use of on-line pressure area relationships to assess RV function in a patient supported with an RV assist device (RVAD). Mid RV short axis cross-sectional area was measured on-line by transesophageal echocardiography with an automated endocardial border detection feature. RV pressure was measured with a high fidelity catheter. Pressure and area were plotted simultaneously on a computer workstation interfaced with the pressure and echo systems to yield on-line pressure area loops. The following indices of RV performance were calculated while RVAD flow was decreased in 1 L/min increments: stroke work' (SW' = integral of PdA)[mmHg*cm2], stroke area (SA = Maximum Area-Minimum Area)[cm2], and fractional area change (FAC = SA/Maximum Area*100)[%]. SW', SA, and FAC significantly increased with decreasing RVAD flow: SW'(from 32 to 61 mmHg*cm2), SA (from 2.58 to 4.37 cm2), and FAC (from 20 to 32%). In conclusion, the increase in these parameters of RV performance with decreasing mechanical assistance suggested that this patient would tolerate removal of the RVAD, which was subsequently successful. This method of on-line pressure area relationships may be useful to predict the need for further mechanical assistance.