Guidelines for the echocardiographic assessment of the right heart in adults: a report from the American Society of Echocardiography endorsed by the European Association of Echocardiography, a registered branch of the European Society of Cardiology, and the Canadian Society of Echocardiography

Cardiac manifestations other than valvulopathy in antiphospholipid syndrome: long-time echocardiography follow-up study

AIM

Non-valvular cardiac disease in the antiphospholipid syndrome (APS) has been scanty studied. We wanted to assess the prevalence and evolution of left myocardial disease, pulmonary hypertension and intracardiac thrombi in a cohort of APS patients.

METHOD

A total of 53 patients with APS, either primary (n = 34, 64%) or associated to lupus (n = 19, 36%) and 20 controls were included. Initial transthoracic echocardiography assessment was performed in patients at diagnosis, with echocardiography controls performed along mean follow-up of 12 years. Prevalence of myocardial disease in APS cohort was assessed taking into account primary risk factors (hemodynamically significant valvular disease, systemic hypertension, diabetes, alcoholism, myocardial infarction or myocarditis), the same as for pulmonary hypertension (severe left ventricular dysfunction or chronic lung disease).

RESULTS

Left myocardial disease had a prevalence of 3.8% (2/53 patients), not different from controls (P = 0.12). Both patients had diastolic dysfunction grade I that maintained stability throughout echocardiographic follow-up period. Pulmonary hypertension had a prevalence of 11.3% (6/53 patients), not different from controls (P = 0.12); all cases were related to pulmonary embolism. Patients diagnosed with pulmonary hypertension in baseline maintained stable pressures throughout follow-up in the absence of new thrombosis. Intracardiac thrombi had a prevalence of 1.8% (1/53 patients), not different from controls (P = 0.4), without changes along echocardiographic follow-up.

CONCLUSION

Pulmonary hypertension is the most prevalent non-valvular cardiac manifestation in APS, with an evolution associated with thromboembolic disease, while left myocardial disease and intracardiac thrombi would be rare manifestations in APS.

The impact of pulmonary hypertension on morbidity and mortality following major lung resection

OBJECTIVES

Pulmonary hypertension is considered a poor prognostic factor for or even a contraindication to major lung resection, but evidence for this claim is lacking. This study evaluates the impact of pulmonary hypertension on morbidity and mortality following pulmonary lobectomy.

METHODS

Adult patients who underwent a lobectomy for cancer and had a transthoracic echocardiogram (TTE) performed within the year prior to the operation were included. Pulmonary hypertension was defined as an estimated right ventricular systolic pressure (RVSP) of ≥36 mmHg by TTE. The preoperative characteristics, intraoperative data and postoperative outcomes of patients with and those without pulmonary hypertension based on TTE were compared. A model for morbidity including published risk factors as well as pulmonary hypertension was developed by multivariable logistic regression.

RESULTS

There were 279 patients without pulmonary hypertension and 19 patients with pulmonary hypertension. Patients with pulmonary hypertension had a lower preoperative forced expiratory volume in 1 s and diffusing capacity of the lung for carbon monoxide than patients without pulmonary hypertension and a higher incidence of tricuspid regurgitation and mitral regurgitation, but the groups were otherwise similar. The mean RVSP in the group of patients with pulmonary hypertension was 47 mmHg. Perioperative mortality (0.0 vs 2.9%; P = 1.0) and postoperative complications (57.9 vs 47.7%; P = 0.48) were not significantly different between patients with and those without pulmonary hypertension. The presence of pulmonary hypertension was not a predictor of adverse outcomes in either univariate or multivariate analysis.

CONCLUSIONS

Lobectomy may be performed safely in selected patients with pulmonary hypertension, with complication rates comparable with those experienced by patients without pulmonary hypertension.

Tissue Doppler imaging in systemic sclerosis: a 3-year longitudinal study

OBJECTIVES

To investigate by standard echocardiography and pulsed-tissue Doppler imaging (TDI) the course of systemic sclerosis (SSc) heart disease and its correlation with epidemiological, clinical, and serological features of the disease and drug treatment.

METHODS

A total of 74 consecutive patients (69 females, between the ages of 19 and 71 years, and disease duration 1-43 years) and 71 controls underwent cardiac assessment at baseline and at 3-year follow-up.

RESULTS

At baseline, compared to controls, patients showed post-Bonferroni correction, impaired left (LV) and right ventricular (RV) diastolic function (Em/Am 0.85 ± 0.4 vs 1.5 ± 0.7, p = 0.0003; Et/At 0.9 ± 0.3 vs 1.3 ± 0.4, p = 0.0003), subtle LV and RV systolic dysfunction (Sm 13.7 ± 2.7 vs 15.4 ± 3.2cm/s, p = 0.031; St < 11.5cm/s in 16/74 patients vs 0 controls, p = 0.0031), and higher pulmonary artery systolic pressure (sPAP) (26.1 ± 6.0 vs 24.1 ± 5.1, p = 0.040). At 3-year follow-up, SSc patients showed a further deterioration of biventricular diastolic and systolic function and a further sPAP increase. At multiple regression analysis of baseline data, Em/Am < 1 was detected in 55/74 patients vs 25/71 controls (p < 0.0001) and was associated with age (p = 0.030); Et/At < 1 was detected in 16/74 patients vs 7/71 controls (p < 0.0001), was associated with NYHA class ≥ II (p = 0.033), late capillaroscopic pattern (p = 0.029), and a baseline cardiac Medsger severity score ≥ 1 (p = 0.029). TDI evidence of new abnormalities in RV and/or LV diastolic function was associated with a baseline cardiac Medsger severity score ≥ 1 (p = 0.01). Neither diastolic or systolic abnormalities nor sPAP changes correlated with treatment.

CONCLUSIONS

Our study confirms that SSc patients exhibit biventricular systolic and diastolic dysfunction and increased sPAP and reveals further deterioration at 3-year follow-up.

Echocardiographic predictors of exercise capacity and mortality in chronic obstructive pulmonary disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) reduces exercise capacity, but lung function parameters do not fully explain functional class and lung-heart interaction could be the explanation. We evaluated echocardiographic predictors of mortality and six minutes walking distance (6MWD), a marker for quality of life and mortality in COPD.

METHODS

Ninety COPD patients (GOLD criteria) were evaluated by body plethysmography, 6MWD and advanced echocardiography parameters (pulsed wave tissue Doppler and speckle tracking).

RESULTS

Mean 6MWD was 403 (± 113) meters. All 90 subjects had preserved left ventricular (LV) ejection fraction 64.3% ± 8.6%. Stroke volume decreased while heart rate increased with COPD severity and hyperinflation. In 66% of patients, some degree of diastolic dysfunction was present. Mitral tissue Doppler data in COPD could be interpreted as a sign of low LV preload and not necessarily an intrinsic impairment in LV relaxation/compliance. Tricuspid regurgitation (TR) increased with COPD severity and hyperinflation. Age (p < 0.001), BMI (p < 0.001), DLCO SB (p < 0.001) and TR (p 0.005) were independent predictors of 6MWD and a multivariable model incorporating heart function parameters (adjusted r2 = .511) compared well to a model with lung function parameters alone (adjusted r2 = .475). LV global longitudinal strain (p = 0.034) was the only independent predictor of mortality among all baseline, body plethysmographic and echocardiographic variables.

CONCLUSIONS

Among subjects with moderate to severe COPD and normal LVEF, GLS independently predicted all-cause mortality. Exercise tolerance correlated with standard lung function parameters only in univariate models; in subsequent models including echocardiographic parameters, longer 6MWD correlated independently with milder TR, better DLCO SB, younger age and lower BMI. We extended the evidence on COPD affecting cardiac chamber volumes, LV preload, heart rate, as well as systolic and diastolic function. Our results highlight lung-heart interaction and the necessity of cardiac evaluation in COPD.

Automatic segmentation of right ventricular ultrasound images using sparse matrix transform and a level set

An automatic segmentation framework is proposed to segment the right ventricle (RV) in echocardiographic images. The method can automatically segment both epicardial and endocardial boundaries from a continuous echocardiography series by combining sparse matrix transform, a training model, and a localized region-based level set. First, the sparse matrix transform extracts main motion regions of the myocardium as eigen-images by analyzing the statistical information of the images. Second, an RV training model is registered to the eigen-images in order to locate the position of the RV. Third, the training model is adjusted and then serves as an optimized initialization for the segmentation of each image. Finally, based on the initializations, a localized, region-based level set algorithm is applied to segment both epicardial and endocardial boundaries in each echocardiograph. Three evaluation methods were used to validate the performance of the segmentation framework. The Dice coefficient measures the overall agreement between the manual and automatic segmentation. The absolute distance and the Hausdorff distance between the boundaries from manual and automatic segmentation were used to measure the accuracy of the segmentation. Ultrasound images of human subjects were used for validation. For the epicardial and endocardial boundaries, the Dice coefficients were 90.8 ± 1.7% and 87.3 ± 1.9%, the absolute distances were 2.0 ± 0.42 mm and 1.79 ± 0.45 mm, and the Hausdorff distances were 6.86 ± 1.71 mm and 7.02 ± 1.17 mm, respectively. The automatic segmentation method based on a sparse matrix transform and level set can provide a useful tool for quantitative cardiac imaging.

Prognostic value of emergency physician performed echocardiography in patients with acute pulmonary thromboembolism

INTRODUCTION

Pulmonary embolism (PE) is a life-threatening illness with high morbidity and mortality. Echocardiography (ECG) plays an important role in the early identification of right ventricular (RV) dysfunction, making it a helpful tool in identifying hemodynamically stable patients affected by PE with a higher mortality risk. The purpose of this study was to evaluate if one or more ECG indexes could predict a short-term evolution towards RV dysfunction.

METHODS

We selected all patients consecutively admitted to the Careggi Hospital Emergency Department with the clinical suspicion of PE, confirmed by computed tomography angiography prior to enrollment. Subsequently, properly trained emergency physicians acquired a complete ECG to measure RV morphological and functional indices. For each patient, we recorded if he or she received a fibrinolytic treatment, a surgical embolectomy or heparin therapy during the emergency department (ED) stay. Then, every patient was re-evaluated with ECG, by the same physician, after 1 week in our intensive observation unit and 1 month as outpatient in our ED regional referral center for PE.

RESULTS

From 2002 to 2007, 120 consecutive patients affected by PE were evaluated by echocardiography at the Careggi Hospital ED. Nine patients (8%) were treated with thrombolytic therapy. Six died within 1 week and 4 abandoned the study, while the remaining 110 survived and were re-evaluated by ECG after 1 week and 1 month. The majority of the echocardiographic RV indexes improve mostly in the first 7 days: Acceleration Time (AT) from 78±14 ms to 117±14 ms (p<0.001), Diameter of Inferior Vena Cava (DIVC) from 25±6 mm to 19±5 mm (p<0.001), Tricuspid Annular Plane Systolic Excursion (TAPSE) from 16±6 mm to 20±6 mm (p<0.001). Pulmonary Artery Systolic Pressure (PASP) showed a remarkable decrease from 59±26 mmHg to 37±9 mmHg, (p<0.001). The measurements of the transverse diameters of both ventricles and the respective ratio showed a progressive normalization with a reduction of RV diameter, an increase of Left Ventricular (LV) diameter and a decrease of RV/LV ratio over time. To evaluate the RV function, the study population was divided into 3 groups based on the TAPSE and PASP mean values at the admission: Group 1 (68 patients) (TAPSE+/ PASP-), Group 2 (12 patients) (TAPSE-/PASP-), and Group 3 (30 patients) (TAPSE-/PASP+). Greater values of AT, minor RV diameter, greater LV diameter and a lesser RV/LV ratio were associated with a short-term improvement of TAPSE in the Group 2. Instead, in Group 3 the only parameter associated with short-term improvement of TAPSE and PASP was the treatment with thrombolytic therapy (p<0.0001).

CONCLUSION

Greater values of AT, minor RV diameter, greater LV diameter and a lesser RV/LV ratio were associated with a short-term improvement of TAPSE-/PASP- values. Patients with evidence of RV dysfunction (TAPSE-/PASP+), may benefit from thrombolytic therapy to improve a short- term RV function. After 1 month, also a decreased DIVC predicted improved RV function.

TRPC4 inactivation confers a survival benefit in severe pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is characterized by elevated pulmonary arterial pressure with lumen-occluding neointimal and plexiform lesions. Activation of store-operated calcium entry channels promotes contraction and proliferation of lung vascular cells. TRPC4 is a ubiquitously expressed store-operated calcium entry channel, but its role in PAH is unknown. We tested the hypothesis that TRPC4 promotes pulmonary arterial constriction and occlusive remodeling, leading to right ventricular failure in severe PAH. Severe PAH was induced in Sprague-Dawley rats and in wild-type and TRPC4-knockout Fischer 344 rats by a single subcutaneous injection of SU5416 [SU (semaxanib)], followed by hypoxia exposure (Hx; 10% O2) for 3 weeks and then a return to normoxia (Nx; 21% O2) for 3 to 10 additional weeks (SU/Hx/Nx). Although rats of both backgrounds exhibited indistinguishable pulmonary hypertensive responses to SU/Hx/Nx, Fischer 344 rats died within 6 to 8 weeks. Normoxic and hypertensive TRPC4-knockout rats recorded hemodynamic parameters similar to those of their wild-type littermates. However, TRPC4 inactivation conferred a striking survival benefit, due in part to preservation of cardiac output. Histological grading of vascular lesions revealed a reduction in the density of severely occluded small pulmonary arteries and in the number of plexiform lesions in TRPC4-knockout rats. TRPC4 inactivation therefore provides a survival benefit in severe PAH, associated with a decrease in the magnitude of occlusive remodeling.

Predictors of diastolic-to-wedge gradient in patients evaluated for pulmonary hypertension

Background

Differentiation of pulmonary arterial hypertension (PAH) and pulmonary venous hypertension (PVH) often requires right heart catheterization (RHC). We sought to determine whether a combination of clinical and echocardiographic variables could predict the pulmonary diastolic to wedge (PAd-PWP) gradient and thus differentiate patients with PAH and PVH.

Methods

We prospectively enrolled 108 patients presenting for PH evaluation. We developed a multivariate model to predict PAd-PWP gradient and validated this model using bootstrapping technique.

Results

PAH patients had worse hemodynamics and were more likely to have evidence of right ventricular dilation and dysfunction whereas patients with PVH were older and more likely to have features of the metabolic syndrome. PAd-PWP gradient of ≥ 6mmHg accurately discriminated patients with PAH compared to PVH. Our model including clinical and echocardiographic variables was highly accurate for the prediction of PAd-PWP gradient with a slope 0.89 (slope of 1 represents perfect prediction).

Conclusions

In this prospective study of patients referred for PH evaluation, a model of readily available clinical parameters and simple echocardiographic measurements accurately predicted the PAd-PWP gradient, allowing discrimination of patients with PAH and PVH. This model requires validation in a larger cohort, but may afford clinicians more parsimony with referral for invasive testing in the evaluation of PH.

Hypovolemia explains the reduced stroke volume at altitude

During acute altitude exposure tachycardia increases cardiac output (Q) thus preserving systemic O₂ delivery. Within days of acclimatization, however, Q normalizes following an unexplained reduction in stroke volume (SV). To investigate whether the altitude-mediated reduction in plasma volume (PV) and hence central blood volume (CBV) is the underlying mechanism we increased/decreased CBV by means of passive whole body head-down (HDT) and head-up (HUT) tilting in seven lowlanders at sea level (SL) and after 25/26 days of residence at 3454 m. Prior to the experiment on day 26, PV was normalized by infusions of a PV expander. Cardiovascular responses to whole body tilting were monitored by pulse contour analysis. After 25/26 days at 3454 m PV and blood volume decreased by 9 ± 4% and 6 ± 2%, respectively (P < 0.001 for both). SV was reduced compared to SL for each HUT angle (P < 0.0005). However, the expected increase in SV from HUT to HDT persisted and ended in the same plateau as at SL, albeit this was shifted 18 ± 20° toward HDT (P = 0.019). PV expansion restored SV to SL during HUT and to an ∼8% higher level during HDT (P = 0.003). The parallel increase in SV from HUT to HDT at altitude and SL to a similar plateau demonstrates an unchanged dependence of SV on CBV, indicating that the reduced SV during HUT was related to an attenuated CBV for a given tilt angle. Restoration of SV by PV expansion rules out a significant contribution of other mechanisms, supporting that resting SV at altitude becomes reduced due to a hypovolemia.

Role of echocardiography in patients with intravascular hemolysis due to suspected continuous-flow LVAD thrombosis

OBJECTIVES

This study sought to characterize the echocardiographic findings of patients presenting with intravascular hemolysis (IVH) due to suspected continuous-flow left ventricular assist device (LVAD) pump thrombosis.

BACKGROUND

LVAD patients who develop pump thrombosis often present with IVH. Echocardiography may be able to detect device dysfunction in this setting.

METHODS

Continuous-flow LVAD patients presenting with IVH due to suspected pump thrombosis were identified. Patients underwent echocardiography with cannula Doppler flow velocity interrogation. Findings were compared with baseline and follow-up studies, and with 49 stable LVAD control patients.

RESULTS

Of 145 patients, 14 (10%) had IVH due to suspected pump thrombosis. The mean age was 55 ± 15 years, 93% were men, and 50% received LVAD as destination therapy. Mean duration between implantation and IVH was 231 ± 218 days. Eleven (79%) patients presented with hemoglobinuria, 9 (64%) with jaundice, and 5 (36%) with acute heart failure. Reduced cannula diastolic flow velocity and increased systolic/diastolic (S/D) flow velocity ratio were the only echocardiographic parameters significantly different from controls (outflow cannula 0.3 ± 0.2 m/s vs. 0.8 ± 0.3 m/s, p = 0.03, and 5.9 ± 2.8 vs. 1.7 ± 0.7, p < 0.01, respectively), and were worse for IVH patients with acute heart failure compared with those without (outflow cannula 0.2 ± 0.1 m/s vs. 0.5 ± 0.2 m/s, p = 0.04, and 7.2 ± 3.3 vs. 5.3 ± 2.0, p = 0.02, respectively). Outflow cannula diastolic flow velocity and S/D flow velocity ratio changed significantly from baseline (p = 0.01 and p < 0.01, respectively) in IVH patients, whereas systolic flow velocity did not change (p = 0.59). Odds ratios for outflow cannula diastolic flow velocity and S/D flow velocity ratio for predicting IVH were 0.60 (95% confidence interval [CI]: 0.51 to 0.73), p = 0.02, and 2.45 (95% CI: 2.37 to 2.52) p < 0.01, respectively. Corresponding inflow cannula values were similarly significant. Pump thrombosis was confirmed in 7 (50%) patients after LVAD retrieval.

CONCLUSIONS

Reduced cannula diastolic flow velocity and increased S/D flow velocity ratio identified continuous-flow LVAD dysfunction in patients with IVH due to suspected pump thrombosis better than other echocardiographic parameters.

Feasibility and reproducibility of systolic right ventricular strain measurement by speckle-tracking echocardiography in premature infants

BACKGROUND

Right ventricular (RV) systolic function is an important prognostic determinant of cardiopulmonary pathologies in premature infants. Measurements of dominant RV longitudinal deformation are likely to provide a sensitive measure of RV function. An approach for image acquisition and postacquisition processing is needed for reliable and reproducible measurements of myocardial deformation by two-dimensional (2D) speckle-tracking echocardiography. The aims of this study were to determine the feasibility and reproducibility of 2D speckle-tracking echocardiographic measurement of RV peak global longitudinal strain (pGLS) and peak global longitudinal strain rate in premature infants and to establish methods for acquiring and analyzing strain.

METHODS

The study was designed in two phases: (1) a training phase to develop methods of image acquisition and postprocessing in a cohort of 30 premature infants (born at 28 ± 1 weeks) and (2) a study phase to prospectively test in a separate cohort of 50 premature infants (born at 27 ± 1 weeks) if the methods improved the feasibility and reproducibility of RV pGLS and peak global longitudinal strain rate measurements to a clinically significant level, assessed using Bland-Altman analysis (bias, limits of agreement, coefficient of variation, and intraclass correlation coefficient).

RESULTS

Strain imaging was feasible from 84% of the acquisitions using the methods developed for optimal speckle brightness and frame rate for RV-focused image acquisition. There was high intraobserver (bias, 3%; 95% limits of agreement, -1.6 to +1.6; coefficient of variation, 2.7%; intraclass correlation coefficient, 0.97; P = .02) and interobserver (bias, 7%; 95% limits of agreement, -4.8 to +4.73; coefficient of variation, 3.9%; intraclass correlation coefficient, 0.93; P < .05) reproducibility, with excellent linear correlation between the two pGLS measurements (r = 0.97 [P < .01] and r = 0.93 [P < .05], respectively).

CONCLUSIONS

This study demonstrates high clinical feasibility and reproducibility of RV pGLS and RV peak global longitudinal strain rate measurements by 2D speckle-tracking echocardiography in premature infants and offers methods for image acquisition and data analysis for systolic strain imaging that can provide a reliable assessment of global RV function.

Rapid weight loss is associated with preoperative hypovolemia in morbidly obese patients

BACKGROUND

In morbidly obese patients (MO), adequate levels of venous return (VR) and left ventricular filling pressures (LVFP) are crucial in order to augment perioperative safety. Rapid weight loss (RWL) preparation with very low calorie diet is commonly used aiming to facilitate bariatric surgery. However, the impact of RWL on VR and LVFP is poorly studied.

METHODS

In this prospective, controlled, single-center study, we hypothesized that RWL-prepared MO prior to bariatric surgery can be hypovolemic (i.e., low VR) and compared MO to lean controls with conventional overnight fasting. Twenty-eight morbidly obese patients were scheduled consecutively for bariatric surgery and 19 lean individuals (control group, CG) for elective general surgery. Preoperative assessment of VR, LVFP, and biventricular heart function was performed by a transthoracic echocardiography (TTE) protocol to all patients in the awake state. Assessment of VR and LVFP was made by inferior vena cava maximal diameter (IVCmax) and inferior vena cava collapsibility index- (IVCCI) derived right atrial pressure estimations.

RESULTS

A majority of MO (71.4 %) were hypovolemic vs. 15.8 % of lean controls (p < 0.001, odds ratio = 13.3). IVCmax was shorter in MO than in CG (p < 0.001). IVCCI was higher in MO (62.1 ± 23 %) vs. controls (42.6 ± 20.8; p < 0.001). Even left atrium anterior-posterior diameter was shorter in MO compared to CG.

CONCLUSIONS

Preoperative RWL may induce hypovolemia in morbidly obese patients. Hypovolemia in MO was more common vs. lean controls. TTE is a rapid and feasible tool for assessment of preload even in morbid obesity.

Association of the frontal QRS-T angle with adverse cardiac remodeling, impaired left and right ventricular function, and worse outcomes in heart failure with preserved ejection fraction

BACKGROUND

No prior studies have investigated the association of QRS-T angle with cardiac structure and function and outcomes in heart failure with preserved ejection fraction (HFpEF). The aim of this study was to test the hypothesis that increased frontal QRS-T angle is associated with worse cardiac function and remodeling and adverse outcomes in HFpEF.

METHODS

A total of 376 patients with HFpEF (i.e., symptomatic heart failure with left ventricular ejection fraction > 50%) were prospectively studied. The frontal QRS-T angle was calculated from the 12-lead electrocardiogram. Patients were divided into tertiles by frontal QRS-T angle (0°-26°, 27°-75°, and 76°-179°), and clinical, laboratory, and echocardiographic data were compared among groups. Cox proportional-hazards analyses were performed to determine the association between QRS-T angle and outcomes.

RESULTS

The mean age of the cohort was 64 ± 13 years, 65% were women, and the mean QRS-T angle was 61 ± 51°. Patients with increased QRS-T angles were older; had lower body mass indices; more frequently had coronary artery disease, diabetes, chronic kidney disease, and atrial fibrillation; and had higher B-type natriuretic peptide levels (P < .05 for all comparisons). After multivariate adjustment, patients with increased QRS-T angles had higher B-type natriuretic peptide levels in addition to higher left ventricular mass indices, worse diastolic function parameters, more right ventricular remodeling, and worse right ventricular systolic function (P < .05 for all associations). QRS-T angle was independently associated with the composite outcome of cardiovascular hospitalization or death on multivariate analysis, even after adjusting for B-type natriuretic peptide (heart rate for the highest QRS-T tertile, 2.0; 95% confidence interval, 1.2-3.4; P = .008).

CONCLUSIONS

In HFpEF, increased QRS-T angle is independently associated with worse left and right ventricular function and remodeling and adverse outcomes.

Fasting 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography to detect metabolic changes in pulmonary arterial hypertension hearts over 1 year

BACKGROUND

The development of tools to monitor the right ventricle in pulmonary arterial hypertension (PAH) is of clinical importance. PAH is associated with pathologic expression of the transcription factor hypoxia-inducible factor (HIF)-1α, which induces glycolytic metabolism and mobilization of proangiogenic progenitor (CD34(+)CD133(+)) cells. We hypothesized that PAH cardiac myocytes have a HIF-related switch to glycolytic metabolism that can be detected with fasting 2-deoxy-2-[(18)F]fluoro-d-glucose positron emission tomography (FDG-PET) and that glucose uptake is informative for cardiac function.

METHODS

Six healthy control subjects and 14 patients with PAH underwent fasting FDG-PET and echocardiogram. Blood CD34(+)CD133(+) cells and erythropoietin were measured as indicators of HIF activation. Twelve subjects in the PAH cohort underwent repeat studies 1 year later to determine if changes in FDG uptake were related to changes in echocardiographic parameters or to measures of HIF activation.

MEASUREMENTS AND RESULTS

FDG uptake in the right ventricle was higher in patients with PAH than in healthy control subjects and correlated with echocardiographic measures of cardiac dysfunction and circulating CD34(+)CD133(+) cells but not erythropoietin. Among patients with PAH, FDG uptake was lower in those receiving β-adrenergic receptor blockers. Changes in FDG uptake over time were related to changes in echocardiographic parameters and CD34(+)CD133(+) cell numbers. Immunohistochemistry of explanted PAH hearts of patients undergoing transplantation revealed that HIF-1α was present in myocyte nuclei but was weakly detectable in control hearts.

CONCLUSIONS

PAH hearts have pathologic glycolytic metabolism that is quantitatively related to cardiac dysfunction over time, suggesting that metabolic imaging may be useful in therapeutic monitoring of patients.

A simple echocardiographic method to estimate pulmonary vascular resistance

Pulmonary hypertension includes heterogeneous diagnoses with distinct hemodynamic pathophysiologic features. Identifying elevated pulmonary vascular resistance (PVR) is critical for appropriate treatment. We reviewed data from patients seen at referral pulmonary hypertension clinics who had undergone echocardiography and right-side cardiac catheterization within 1 year. We derived equations to estimate PVR using the ratio of estimated pulmonary artery (PA) systolic pressure (PASPDoppler) to right ventricular outflow tract velocity time integral (VTI). We validated these equations in a separate sample and compared them with a published model based on the ratio of the transtricuspid flow velocity to right ventricular outflow tract VTI (model 1, Abbas et al 2003). The derived models were as follows: PVR = 1.2 × (PASP/right ventricular outflow tract VTI) (model 2) and PVR = (PASP/right ventricular outflow tract VTI) + 3 if notch present (model 3). The cohort included 217 patients with mean PA pressure of 45.3 ± 11.9 mm Hg, PVR of 7.3 ± 5.0 WU, and PA wedge pressure of 14.8 ± 8.1 mm Hg. Just >1/3 had a PA wedge pressure >15 mm Hg (35.5%) and 82.0% had PVR >3 WU. Model 1 systematically underestimated catheterization estimated PVR, especially for those with high PVR. The derived models demonstrated no systematic bias. Model 3 correlated best with PVR (r = 0.80 vs r = 0.73 and r = 0.77 for models 1 and 2, respectively). Model 3 had superior discriminatory power for PVR >3 WU (area under the curve 0.946) and PVR >5 WU (area under the curve 0.924), although all models discriminated well. Model 3-estimated PVR >3 was 98.3% sensitive and 61.1% specific for PVR >3 WU (positive predictive value 93%; negative predictive value 88%). In conclusion, we present an equation to estimate the PVR, using the ratio of PASPDoppler to right ventricular outflow tract VTI and a constant designating presence of right ventricular outflow tract VTI midsystolic notching, which provides superior agreement with catheterization estimates of PVR across a wide range of values.

Echocardiographic assessment of right ventricular function in inferior wall myocardial infarction and angiographic correlation to proximal right coronary artery stenosis

BACKGROUND

Presence of right ventricular (RV) infarction imposes a higher risk of adverse events in inferior wall myocardial infarction (IWMI). In this study, we attempted to correlate various indices of RV function assessed by echocardiography with presence of a proximal right coronary artery (RCA) stenosis in patients with first episode of acute IWMI.

METHODS

In a prospective study, patients with first episode of acute IWMI underwent echocardiographic assessment within 24 h of symptom onset and indices of RV function viz. RV fractional area change (RVFAC), tricuspid annular plane systolic excursion (TAPSE), myocardial performance index (MPI) and tissue Doppler velocities from RV free wall were measured. Patients who underwent coronary angiogram (CAG) within one month and they were classified into group 1 and group 2 based on the presence or absence, respectively, of a significant proximal RCA stenosis.

RESULTS

There were 90 patients with first episode of IWMI of which 67 patients underwent CAG. There was significant difference between group 1 (n = 26) and group 2 (n = 41) in TAPSE (13.5 ± 1.3 vs 21.3 ± 1.7, p < 0.001), MPI by tissue Doppler (0.87 ± 0.1 vs 0.55 ± 0.2, p < 0.001) and in tissue Doppler systolic velocity from RV free wall (S' 9.8 ± 1.1 vs 15.0 ± 1.5, p < 0.001). There was a good interobserver correlation for TAPSE, MPI by TDI, and S' velocity. TAPSE ≤ 16 (sensitivity 93%, specificity 100%), MPI-TDI ≥ 0.69 (sensitivity 94.7%, specificity 93.5%), S ≤ 12.3 (sensitivity 90.3%, specificity 94.3%) were useful in predicting presence of proximal RCA stenosis.

CONCLUSION

RV function indices like TAPSE, MPI-TDI and S' velocity are useful in predicting proximal RCA stenosis in first episode of acute IWMI.

The association of a panel of biomarkers with the presence and severity of carcinoid heart disease: a cross-sectional study

Purpose

Metastatic neuroendocrine tumors secrete serotonin and other vasoactive substances that are responsible for carcinoid syndrome and carcinoid heart disease. We sought to evaluate the discriminatory utility of diagnostic biomarkers in determining the presence and severity of carcinoid heart disease in patients with metastatic neuroendocrine tumors.

Patients and methods

A cross-sectional study of patients with neuroendocrine tumors with documented liver metastases and/or carcinoid syndrome between April 2009–October 2012 in 5 tertiary referral centers. Serum was analyzed for Chromogranin A, Chromogranin B and N-terminal pro Brain Natriuretic Peptide (NT-proBNP). Plasma was analyzed for Neurokinin A and 5-Hydroxyindoleacetic acid (5HIAA). Echocardiography was used to determine the presence and severity of carcinoid heart disease. Non-parametric receiver operating characteristic curves were constructed for biomarkers, and the area under the curve determined. The severity of cardiac involvement was correlated with the concentration of each biomarker.

Results

A total of 187 patients were identified of whom 37 (20%) had carcinoid heart disease. Significantly higher median values of all biomarkers were found in the patients with cardiac involvement. NT-proBNP and plasma 5HIAA had the highest areas under the curve for the prediction of carcinoid heart disease [NT-proBNP 0.82 (95% confidence interval 0.74–0.90, p<0.0001) and 5HIAA 0.85 (95% confidence interval 0.78–0.92, p<0.0001]. NT-proBNP was moderately correlated (r = 0.48, p<0.001) whereas plasma 5HIAA was only weakly correlated (r = 0.34, p<0.001) with the echocardiographic severity score.

Conclusion

NT-proBNP and plasma 5HIAA are both sensitive and specific biomarkers for the presence of carcinoid heart disease whereas only NT-proBNP is moderately correlated with disease severity.

Load Dependency of Right Ventricular Performance Is a Major Factor to be Considered in Decision Making Before Ventricular Assist Device Implantation

Background—

Left ventricular assist devices (LVADs) provide better outcome than biventricular devices, but it is a challenge to predict the impact of LV mechanical unloading on postoperative right ventricular (RV) function preoperatively. We assessed the load dependency in RV performance before and after LVAD implantation aiming to improve preoperative decision making.

Methods and Results—

Laboratory, echocardiography, and right heart catheterization data collected from 205 patients before LVAD implantation were tested for relationship with postoperative RV function. Comparing patients with different time-course of RV function after LVAD implantation, we found significant differences ( P <0.01) in preoperative RV end-diastolic short-/long-axis and long-axis/length-area ratios, tricuspid annulus peak systolic velocity, RV peak longitudinal global systolic strain rate, systolic pressure gradient between RV and right atrium (Δ P RV−RA ), tricuspid regurgitation velocity-time integral, and pulmonary arterial pressure between patients with and without postoperative RV failure. High predictive values for postoperative RV failure were found for end-diastolic short-/long-axis ratio ≥0.6, tricuspid annulus peak systolic velocity <8 cm/s, and peak systolic longitudinal strain rate <0.6/s in patients with maximum Δ P RV−RA <35 mm Hg. These parameters also seemed predictive for RV failure in patients with tricuspid regurgitation grade >2 and pulmonary arterial pressure <50 mm Hg. End-diastolic short-/long-axis ratio <0.6, tricuspid annulus peak systolic velocity ≥8 cm/s, and peak systolic longitudinal strain rate ≥0.6 in patients with maximum Δ P RV−RA ≥35 mm Hg showed high predictive values for postoperative freedom from RV failure. The RV load adaptation index seemed particularly predictive for RV function after LVAD implantation.

Conclusions—

RV geometry and velocity of contraction before LVAD implantation become more predictive for postoperative RV function and can improve decision making before VAD implantation if preoperative RV pressure load and tricuspid regurgitation are also considered.

Provider recognition and response to echocardiographic findings indicating pulmonary hypertension in the Veterans affairs medical center population

PH occurs alone or in association with many disorders. Many patients with transthoracic echocardiography (TTE) findings suggesting PH never receive additional evaluation. Patient characteristics and echocardiographic data associated with increased recognition of PH have not been fully evaluated. We evaluated TTE reports at the Cincinnati Veterans Affairs Medical Center from 2005 to 2006 retrospectively for findings highly indicative of PH: Estimated systolic pulmonary artery pressure (sPAP) ≥40 mmHg, increased right atrial or right ventricular (RV) size, or reduced RV function. Only patients with left ventricular ejection fraction (LVEF) ≥50% and no known diagnosis of PH were included. Patient characteristics, TTE findings, provider recognition rates, and subsequent referral for additional evaluation were assessed. A total of 227 of 3,960 (5.7%) TTE reports revealed findings indicating possible PH. Providers acknowledged possible PH in 53 (23.4%) reports. Recognized PH was predicted by increased RV size (odds ratio (OR) = 5.07, P < 0.001), increased right atrial dimension (OR = 6.45, P < 0.001), decreased RV function (OR = 8.86, P < 0.001), and increased PAP (OR = 1.04 corresponding to each unit increase of PAP, P < 0.01). Patients with comorbid obstructive sleep apnea (OSA), interstitial lung disease, and dyspnea were also more likely to be recognized (OR = 3.63, P = 0.021; OR = 10.98, P = 0.004; OR = 2.39, P = 0.007, respectively). The 12-month mortality rate for recognized patients, 11.3% (7/53), was lower than for unrecognized patients, 25.3% (44/174; P = 0.03). Providers recognized less than one in four patients with echocardiographic evidence suggesting PH. Echocardiography reports revealing higher PAP and right heart dilation and dysfunction are associated with increased acknowledgement of possible PH.

Tricuspid annular plane systolic excursion for the assessment of ventricular function in adults operated on with mustard procedure for complete transposition of the great arteries

BACKGROUND

In adult patients with d-transposition of the great arteries after atrial switch operation, dysfunction of the systemic right ventricle (RV) is a well-known complication. Echocardiographic variables may provide adequate estimation of subpulmonary RV function, but their applicability to the subaortic RV is not straightforward. We evaluate the concordance between tricuspid annular plane systolic excursion (TAPSE) and magnetic resonance imaging-derived ejection fraction of the RV (MRI-RVEF) in these patients.

METHODS

Patients were recruited from those evaluated at the adult congenital clinic of our department between 2010 and 2012. All patients who had an echocardiographic assessment within 6 months of their MRI examination were selected. Patients clinically unstable, not in sinus rhythm, with a prosthetic systemic atrioventricular valve, permanent pacemaker, or more than moderate systemic atrioventricular valve regurgitation were excluded.

RESULTS

Eighteen Mustard-operated patients aged 22 ± 3.7 years were studied. The mean values of TAPSE and RVEF were 13.22 ± 1.7 mm and 49.7 ± 6%, respectively. TAPSE and RVEF were normal in 1 (5.5%) and 10 (55.5%) patients, respectively. Seventeen (94.4%) patients showed reduced TAPSE (12.9 ± 1.3 mm): RVEF was reduced in eight (47%) of these subjects, and normal in nine (53%). In patients with normal RVEF, both the MRI-RV end-diastolic and the MRI-RV end-systolic volumes were significantly lower than in patients with reduced RVEF. There were no other statistically significant differences between these patients. No correlation was found between TAPSE and both the MRI-RV end-diastolic and the end-systolic volumes. Globally, agreement between TAPSE and RVEF was slight (K = 0.09 ± 0.089).

CONCLUSIONS

Our results indicate that in these patients TAPSE is not a useful measure of RV function.

Circadian blood pressure pattern and right ventricular and right atrial mechanics: A two- and three-dimensional echocardiographic study

The purpose of this investigation was to evaluate right ventricular (RV) and right atrial (RA) function and mechanics in untreated hypertensive patients with different blood pressure (BP) patterns by using two-dimensional (2DE) speckle tracking analyses and three-dimensional echocardiography (3DE). This cross-sectional study included 174 recently diagnosed hypertensive patients. All patients underwent a 24-hour ambulatory BP monitoring and complete 2DE and 3DE examination, including 2DE speckle tracking analysis. Our results showed that 2DE RV global longitudinal strain was significantly lower in the non-dippers. Similar results were obtained for 2DE RV systolic and early diastolic strain rate. The RA longitudinal strain, as well as RA systolic and early diastolic strain rate, was decreased in non-dippers. Our results revealed that 3DE RV end-diastolic and end-systolic volumes were increased, whereas 3DE RV ejection fraction was reduced in non-dipper hypertensive patients. Similar results were obtained for RA volumes and RA ejection fraction estimated by 2DE. Independent predictors of 3DE RV ejection fraction, 2DE RV and RA global longitudinal strain were left ventricular mass index and RV wall thickness. An additional independent predictor of the RV longitudinal strain was 3DE RV ejection fraction, and for RA longitudinal strain, an additional independent predictor was tricuspid E/é ratio. Two-DE speckle tracking evaluation and 3DE examination revealed that the RV and RA function and mechanics were more deteriorated in the non-dipper patients than in dipper untreated hypertensive patients.

Size matters! Impact of age, sex, height, and weight on the normal heart size

BACKGROUND

Therapeutic decisions in cardiology are determined frequently by cardiac chamber size. To decide whether cardiac dimensions are still in the normal range, reliable reference values are needed. However, published reference values mostly refer to historical cohorts using motion-mode measurements and have not been adjusted for sex or age. The impact of body size was only vaguely addressed. The importance of such adjustments is illustrated by studies, which show that smaller individuals and women are at risk of delayed treatment and impaired outcome when currently used reference values are applied. The aim of the present study was to assess the impact of body size, sex, and age on the normal heart size.

METHODS AND RESULTS

We prospectively studied 622 individuals (52.7% women; 17-91 years; 143-200 cm; 32-240 kg) without cardiac disease by standard transthoracic echocardiography. Multivariable linear regression analyses of the impact of sex, age, height, and weight on cardiac chamber size were performed. By multivariable regression analysis (n=500), all 4 variables independently influenced cardiac chamber size. The validity of cardiac dimensions predicted by the regression model was tested prospectively in a validation cohort (n=122). A calculator is proposed that estimates cardiac dimensions on the basis of the regression analysis.

CONCLUSIONS

Sex, height, weight, and age significantly affect the normal heart size. These parameters need to be considered when cutoff values indicating the need for treatment or even surgery are established.

Role of pretransplant echocardiographic evaluation in predicting outcomes following liver transplantation

Maintenance of cardiac function is critical to the survival of patients with end-stage liver disease after liver transplantation (LT). We sought to determine whether pre-LT echocardiographic indices of right heart structure and function were independently predictive of morbidity and mortality post-LT. We retrospectively studied 216 consecutive patients who underwent pre-LT 2-dimensional/Doppler echocardiography with subsequent LT from 2007 to 2010. A blinded reader analyzed multiple echocardiographic parameters, including right ventricular structure and function, pulmonary artery systolic pressure (PASP) and the presence and severity of tricuspid regurgitation (TR). On univariate analysis, Model of End-Stage Liver Disease (MELD) score, PASP, presence of ≥mild TR, post-operative renal replacement therapy (RRT) and spontaneous bacterial peritonitis were found to be significant predictors of adverse outcomes. On multivariate analysis, only ≥mild TR was found to predict both patient mortality (p = 0.0024, HR = 3.91, 95% CI: 1.62-9.44) and graft failure (p = 0.0010, HR = 3.70, 95% CI: 1.70-8.06). PASP and MELD correlated with post-LT intensive care unit length of stay (LOS) and, along with hemodialysis, were associated with hospital LOS and time on ventilator. In conclusion, pre-LT echocardiographic assessments of the right heart may be useful in predicting post-LT morbidity and mortality and guiding the selection of appropriate LT candidates.