Evaluation of left ventricular filling pressure by echocardiography: incremental diagnostic information from left atrial strain

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): South-Eastern Norway Regional Health Authority

Background

Elevated left ventricular (LV) filling pressure is an important diagnostic feature of heart failure.

Objectives

To investigate determinants of left atrial (LA) reservoir and pump strain and if these parameters may serve as markers of LV filling pressure.

Methods

In a multicenter study of 322 patients with cardiovascular disease of different etiologies, LA strain by speckle tracking echocardiography was compared to conventional echocardiographic markers using invasive pressure as reference.

Results

Left ventricular filling pressure correlated well with LA reservoir and pump strain (r-values

‑0.52 and ‑0.57, respectively) (Figure). However, LV global longitudinal strain (GLS) was the strongest determinant of LA reservoir strain (r = 0.64), and correlated well with LA pump strain (r = 0.51).  For both LA strains, association with filling pressure was strongest in patients with reduced LV ejection fraction. In patients with normal GLS (≥18%), atrial strains provided no information regarding filling pressure (Figure). Reservoir strain <18% and pump strain <8% predicted elevated LV filling pressure better (p < 0.05) than the conventional indices LA volume, ratio of mitral early filling velocity/annular velocity and tricuspid regurgitation velocity. Accuracy to classify filling pressure as normal or elevated was 75% for both LA strains . When any one of the conventional indices were missing, and were replaced by LA strains, the combination of indices had accuracy 82% to correctly classify filling pressure.

Conclusions

Left atrial reservoir and pump strain may serve as clinical markers of LV filling pressure, but will be useful predominantly in patients with reduced systolic function.  Due to limited diagnostic accuracy, LA strain should be used in combination with other indices.

Abstract Figure

Association of Lymphangiogenic Factors With Pulmonary Arterial Hypertension in Systemic Sclerosis

OBJECTIVE

Pulmonary arterial hypertension (PAH) is a major complication in systemic sclerosis (SSc), a disease marked by vascular and lymphatic vessel abnormalities. This study was undertaken to assess the role of the lymphangiogenic factors vascular endothelial growth factor C (VEGF-C) and angiopoietin 2 (Ang-2) and the soluble forms of their respective cognate receptors, soluble VEGF receptor 3 (sVEGFR-3) and soluble TIE-2, in patients with SSc, and to evaluate their predictive ability as markers for PAH development in SSc.

METHODS

In this cohort study, we used multiplex bead assays to assess serum levels of lymphangiogenic factors in 2 well-characterized SSc cohorts: an unselected identification cohort of SSc patients from Oslo University Hospital (n = 371), and a PAH-enriched validation cohort of SSc patients from Zurich University Hospital and Oslo University Hospital (n = 149). As controls for the identification and validation cohorts, we obtained serum samples from 100 healthy individuals and 68 healthy individuals, respectively. Patients in whom SSc-related PAH was identified by right-sided heart catheterization (RHC) in both cohorts were studied in prediction analyses. PAH was defined according to the European Society of Cardiology/European Respiratory Society 2015 guidelines for the diagnosis and treatment of PAH. Associations of serum levels of lymphangiogenic factors with the risk of PAH development were assessed in logistic regression and Cox regression analyses. Associations in Cox regression analyses were expressed as the hazard ratio (HR) with 95% confidence interval (95% CI).

RESULTS

In the identification cohort, SSc patients had lower mean serum levels of VEGF-C and higher mean serum levels of Ang-2 compared to healthy controls (for VEGF-C, mean ± SD 2.1 ± 0.5 ng/ml in patients versus 2.5 ± 0.4 ng/ml in controls; for Ang-2, mean ± SD 6.1 ± 7.6 ng/ml in patients versus 2.8 ± 1.8 ng/ml in controls; each P < 0.001); these same trends were observed in SSc patients with PAH compared to those without PAH. The association of serum VEGF-C levels with SSc-PAH was confirmed in the PAH-enriched RHC validation cohort. For prediction analyses, we assembled all 251 cases of SSc-PAH identified by RHC from the identification and validation cohorts. In multivariable Cox regression analyses adjusted for age and sex, the mean serum levels of VEGF-C and sVEGFR-3 were predictive of PAH development in patients with SSc (for VEGF-C, HR 0.53 [95% CI 0.29-0.97], P = 0.04; for sVEGFR-3, HR 1.21 [95% CI 1.01-1.45], P = 0.042).

CONCLUSION

These findings support the notion that lymphangiogenesis is deregulated during PAH development in SSc, and indicate that VEGF-C could be a promising marker for early PAH detection in patients with SSc.

Determinants of left atrial reservoir and pump strain and use of atrial strain for evaluation of left ventricular filling pressure

AIMS

The aim of this study is to investigate determinants of left atrial (LA) reservoir and pump strain and if these parameters may serve as non-invasive markers of left ventricular (LV) filling pressure.

METHODS AND RESULTS

In a multicentre study of 322 patients with cardiovascular disease of different aetiologies, LA strain and other echocardiographic parameters were compared with invasively measured LV filling pressure. The strongest determinants of LA reservoir and pump strain were LV global longitudinal strain (GLS) (r-values 0.64 and 0.51, respectively) and LV filling pressure (r-values -0.52 and -0.57, respectively). Left atrial volume was another independent, but weaker determinant of both LA strains. For both LA strains, association with LV filling pressure was strongest in patients with reduced LV ejection fraction. Left atrial reservoir strain <18% and LA pump strain <8% predicted elevated LV filling pressure better (P < 0.05) than LA volume and conventional Doppler parameters. Accuracy to identify elevated LV filling pressure was 75% for LA reservoir strain alone and 72% for pump strain alone. When combined with conventional parameters, accuracy was 82% for both LA strains. In patients with normal LV systolic function by GLS, LA pump strain >14% identified normal LV filling pressure with 92% accuracy.

CONCLUSION

Left atrial reservoir and pump strain are determined predominantly by LV GLS and filling pressure. Accuracy of LA strains to identify elevated LV filling pressure was best in patients with reduced LV systolic function. High values of LA pump strain, however, identified normal LV filling pressure with good accuracy in patients with normal systolic function.

Long-term effects of high-intensity training vs moderate intensity training in heart transplant recipients: A 3-year follow-up study of the randomized-controlled HITTS study

The randomized controlled High-Intensity Interval Training in De Novo Heart Transplant Recipients in Scandinavia (HITTS) study compared 9 months of high-intensity interval training (HIT) with moderate intensity continuous training in de novo heart transplant recipients. In our 3-year follow-up study, we aimed to determine whether the effect of early initiation of HIT on peak oxygen consumption (VO_2peak ) persisted for 2 years postintervention. The study's primary end point was the change in VO_2peak (mL/kg/min). The secondary end points were muscle strength, body composition, heart rate response, health-related quality of life, daily physical activity, biomarkers, and heart function. Of 78 patients who completed the 1-year HITTS trial, 65 entered our study and 62 completed the study tests. VO_2peak increased from baseline to 1 year and leveled off thereafter. During the intervention period, the increase in VO_2peak was larger in the HIT arm; however, 2 years later, there was no significant between-group difference in VO_2peak . However, the mean change in the anaerobic threshold and extensor muscle endurance remained significantly higher in the HIT group. Early initiation of HIT after heart transplantation appears to have some sustainable long-term effects. Clinical trial registration number: NCT01796379.

Assessment of left ventricular filling pressure: left atrial reservoir strain is an excellent replacement for missing tricuspid regurgitation velocity

Background

When evaluating left ventricular filling pressure (LVFP) according to current guidelines, tricuspid regurgitation (TR) velocity is often not available.

Purpose

In the present study we investigate if left atrial (LA) reservoir strain may be used instead of TR velocity for evaluation of LVFP.

Methods

We performed a prospective, multicenter, multinational and multivendor study in an all comer population of 322 patients with suspected heart failure or other cardiovascular disease where LVFP was measured by right- or left heart catheterization, as pulmonary capillary wedge pressure or pre-A LV diastolic pressure, respectively. Echocardiography was performed within 1 day of catheterization.

101 patients classified as special populations in the 2016 ASE/EACVI recommendations (i.e. non-cardiac pulmonary hypertension, atrial fibrillation, hypertrophic and restrictive cardiomyopathies) were excluded. Of the remaining 221 patients, 118 patients had EF ≥50% and 103 patients had EF &lt;50%. Regression analysis was performed for LA reservoir strain and TR velocity against LVFP. LA reservoir strain at a cut-off value of &lt;18% was applied instead of TR velocity in the 2016 ASE/EACVI algorithm and compared with the current algorithm.

Results

LA reservoir strain correlated better with LVFP than TR velocity, r=0.62 vs 0.40 (p&lt;0.01) (Figure 1). When replacing TR velocity with LA reservoir strain, the feasibility of the ASE/EACVI 2016 algorithm increased from 91.8% to 98.1%. The accuracy of the algorithm was not significantly altered (80% vs 79%).

An accuracy of 80% for the algorithm is lower than what has been reported in earlier publications, this may be due to inclusion of patients without suspected heart failure and no assessment of clinical data, which in turn may have influenced the accuracy of the algorithm.

Conclusion

LA reservoir strain has better correlation to LVFP than TR velocity, and can be used in the ASE/EACVI 2016 algorithm for estimation of LVFP as a replacement when TR velocity is missing.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): South-Eastern Norway Regional Health Authority

Which single echo parameter is the best marker of left ventricular filling pressure?

Background

Estimation of left ventricular filling pressure (LVFP) is highly relevant in clinical practice. Invasive pressure remains the gold standard, but a number of echocardiographic parameters that correlate with LVFP are used as non-invasive markers of pressure.

Purpose

We investigated how different echocardiographic parameters correlated with invasively measured LVFP, and how accurately those parameters could differentiate between normal or elevated LVFP.

Method

We performed a prospective, multicenter, multinational and multivendor study in an all comer population of 322 patients with suspected heart failure or other cardiovascular disease. 194 patients had EF ≥50% and 129 had EF &lt;50%. LVFP was measured by right- or left heart catheterization, as pulmonary capillary wedge pressure or pre-A LV diastolic pressure, respectively.

When excluding all special patient populations defined in the 2016 recommendations for echocardiographic evaluation of LV diastolic function, 213 patients remained. Of these 135 had EF ≥50% and 74 had EF &lt;50%.

Echocardiography was performed within 1 day of catheterization. Previously recommended cut-off values for established parameters were used to determine the accuracy of classifying LVFP as normal or elevated. For left atrial (LA) reservoir strain, based on ROC analysis, a cut-off value of &lt;18% was used as marker of elevated LVFP.

Results

LA reservoir strain and the ratio of peak mitral early flow velocity (E) and LA reservoir strain (E/LA strain) showed the best correlations to LVFP (Table 1, Figure 1). They also had the highest accuracy, 75% for both, in classifying LVFP as normal or elevated in the whole patient population. E/LA reservoir strain provided no additional diagnostic value to using LA reservoir strain alone.

In HFpEF patients accuracy was essentially similar for LA strain, E/LA strain and E/e', whereas in HFrEF patients the two former tended to be better than E/e'.

Conclusion

Parameters containing LA reservoir strain showed the best correlation to LVFP. This indicates that LA reservoir strain may have a role in evaluation of LVFP.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): South-Eastern Norway Regional Health Authority

High-intensity interval training and health-related quality of life in de novo heart transplant recipients - results from a randomized controlled trial

Background

Studies on the effect of high-intensity interval training (HIT) compared with moderate intensity continuous training (MICT) on health-related quality of life (HRQoL) after heart transplantation (HTx) is scarce. No available studies among de novo HTx recipients exists. This study aimed to investigate the effect of HIT vs. MICT on HRQoL in de novo recipients.

Methods

The HITTS study randomized eighty-one de novo HTx recipients to receive either HIT or MICT (1:1). The HIT intervention were performed with 2–4 interval bouts with an intensity of 85–95% of maximal effort. The MICT group exercised at an intensity of 60–80% of their maximal effort with a duration of 25 min. HRQoL was assessed by the Short Form-36 version 2 (SF-36v2) and the Hospital Anxiety and Depression Scale, mean 11 weeks after surgery and after a nine months’ intervention. The participants recorded their subjective effect of the interventions on their general health and well-being on a numeric visual analogue scale. Clinical examinations and physical tests were performed. Differences between groups were investigated with independent Student t-tests and with Mann-Whitney U tests where appropriate. Within-group differences were analyzed with Paired-Sample t-tests and Wilcoxon Signed Rank tests. Correlations between SF-36 scores and VO_2peak were examined with Pearson’s correlations.

Results

Seventy-eight participants completed the intervention. Both exercise modes were associated with improved exercise capacity on the physical function scores of HRQoL. Mental health scores remained unchanged. No differences in the change in HRQoL between the groups occurred except for Role Emotional subscale with a larger increase in the HIT arm. Better self-reported physical function was associated with higher VO_2peak and muscle strength.

Conclusion

HIT and MICT resulted in similar mean changes in HRQoL the first year after HTx. Both groups experienced significant improvements in the physical SF-36v2.

Trial registration

ClinicalTrials.gov number: NCT01796379 Registered 18 February 2013.

A Middle-Aged Man Presenting With Progressive Heart Failure, Myopathy, and Monoclonal Gammopathy of Uncertain Significance

A 48-year-old man presented with rapidly progressive heart failure and monoclonal gammopathy of uncertain significance. No specific cause was detected on endomyocardial biopsy. As the heart failure worsened, he also developed progressive skeletal myopathy. This provided the clue to the diagnosis, and cardiac function recovered rapidly with cause-directed therapy. (Level of Difficulty: Intermediate.)

Effect of High-Intensity Interval Training in De Novo Heart Transplant Recipients in Scandinavia

BACKGROUND

There is no consensus on how, when, or at what intensity exercise should be performed after heart transplantation (HTx). We have recently shown that high-intensity interval training (HIT) is safe, well tolerated, and efficacious in the maintenance state after HTx, but studies have not investigated HIT effects in the de novo HTx state. We hypothesized that HIT could be introduced early after HTx and that it could lead to clinically meaningful increases in exercise capacity and health-related quality of life.

METHODS

This multicenter, prospective, randomized, controlled trial included 81 patients a mean of 11 weeks (range, 7-16 weeks) after an HTx. Patients were randomized 1:1 to 9 months of either HIT (4×4-minute intervals at 85%-95% of peak effort) or moderate-intensity continuous training (60%-80% of peak effort). The primary outcome was the effect of HIT versus moderate-intensity continuous training on the change in aerobic exercise capacity, assessed as the peak oxygen consumption (Vo₂peak). Secondary outcomes included tolerability, safety, adverse events, isokinetic muscular strength, body composition, health-related quality of life, left ventricular function, hemodynamics, endothelial function, and biomarkers.

RESULTS

From baseline to follow-up, 96% of patients completed the study. There were no serious exercise-related adverse events. The population comprised 73% men, and the mean±SD age was 49±13 years. At the 1-year follow-up, the HIT group demonstrated greater improvements than the moderate-intensity continuous training group; the groups showed significantly different changes in the Vo₂peak (mean difference between groups, 1.8 mL·kg^-1·min^-1), the anaerobic threshold (0.28 L/min), the peak expiratory flow (11%), and the extensor muscle exercise capacity (464 J). The 1.8-mL·kg^-1·min^-1 difference was equal to ≈0.5 metabolic equivalents, which is regarded as clinically meaningful and relevant. Health-related quality of life was similar between the groups, as indicated by results from the Short Form-36 (version 2), Hospital Anxiety and Depression Scale, and a visual analog scale.

CONCLUSIONS

We demonstrated that HIT was a safe, efficient exercise method in de novo HTx recipients. HIT, compared with moderate-intensity continuous training, resulted in a clinically significantly greater change in exercise capacity based on the Vo₂peak values (25% versus 15%), anaerobic threshold, peak expiratory flow, and muscular exercise capacity.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov . Unique identifier NCT01796379.

Invasive haemodynamics in de novo everolimus vs. calcineurin inhibitor heart transplant recipients

Aims

Invasive haemodynamic profiles at rest and during exercise after heart transplantation (HTx) have never been described in a randomized trial where de novo everolimus (EVR)‐based therapy with early calcineurin inhibitor (CNI) withdrawal has been compared with conventional CNI treatment. We report central invasive haemodynamic parameters at rest and exercise during a 3 year follow‐up after HTx in a sub‐study of the SCandiavian Heart transplant Everolimus De novo stUdy with earLy calcineurin inhibitor avoidancE trial. We hypothesized that the nephroprotective properties, the less development of cardiac allograft vasculopathy (CAV), and the antifibrotic properties of EVR, in comparison with CNI‐based immunosuppression, would demonstrate favourable invasive haemodynamic profiles in patients at rest and during exercise.

Methods and results

Ninety of 115 HTx recipients randomized to EVR or CNI treatment performed right heart catheterization at rest and 68 performed right heart catheterization at exercise up to 3 years after HTx. Haemodynamic profiles were compared between EVR and CNI treatment groups. Resting haemodynamics improved in both groups from pre‐HTx to the first follow‐up at 7–11 weeks post‐HTx and thereafter remained unchanged up to 3 years of follow‐up. During follow‐up, cardiac reserve during exercise increased with higher levels of maximum heart rate (118 to 148 b.p.m., P < 0.001), mean arterial pressure (103 to 128 mmHg, P < 0.001), and cardiac output (10.3 to 12.2 l/min, P < 0.001). No significant differences in haemodynamic parameters were observed between the EVR and CNI groups at rest or exercise. Isolated post‐capillary pulmonary hypertension (mean pulmonary arterial pressure > 20 mmHg, pulmonary arterial wedge pressure ≥ 15 mmHg, and pulmonary vascular resistance <3) were measured in 11% of the patients at 7–11 weeks, 5% at 12 months, and 6% at 36 months after HTx. The EVR group had significantly better kidney function (76 mL/min/1 vs. 60 mL/min/1, P < 0.001) and reduced CAV (P < 0.01) but an increased rate of early biopsy‐proven treated rejections (21.2% vs 5.7%, P < 0.01) compared with the CNI group at any time point. The differences in renal function, CAV, or early biopsy‐proven treated acute rejections were not associated with altered haemodynamics.

Conclusions

De novo EVR treatment with early CNI withdrawal compared with conventional CNI therapy did not result in differences in haemodynamics at rest or during exercise up to 3 years after HTx despite significant differences in renal function, reduced CAV, and number of early biopsy‐proven treated rejections.

Mild acute cellular rejection and development of cardiac allograft vasculopathy assessed by intravascular ultrasound and coronary angiography in heart transplant recipients-a SCHEDULE trial substudy

To evaluate the association between mild acute cellular rejection (ACR) and the development of cardiac allograft vasculopathy (CAV) after heart transplantation (HTx). Substudy of the SCHEDULE trial (n = 115), where de novo HTx recipients were randomized to (i) everolimus with early CNI elimination or (ii) CNI-based immunosuppression. Seventy-six patients (66%) were included based on matched intravascular ultrasound (IVUS) examinations at baseline and year 3 post-HTx. Biopsy-proven ACR within year 1 post-HTx was recorded and graded (1R, 2R, 3R). Development of CAV was assessed by IVUS and coronary angiography at year 3 post-HTx. Median age was 53 years (45-61), and 71% were male. ACR was recorded in 67%, and patients were grouped by rejection profile: no ACR (33%), only 1R (42%), and ≥2R (25%). Median ∆MIT (maximal intimal thickness)_BL-3Y was not significantly different between groups (P = 0.84). The incidence of CAV was 49% by IVUS and 26% by coronary angiography with no significant differences between groups. No correlation was found between number of 1R and ∆MIT_BL-3Y (r = -0.025, P = 0.83). The number of 1R was not a significant predictor of ∆MIT_BL-3Y (P = 0.58), and no significant interaction with treatment was found (P = 0.98). The burden of mild ACR was not associated with CAV development.

1231 Left atrial septal and lateral wall strains contain different pressure information: Utility in pulmonary hypertension

Funding Acknowledgements

South-Eastern Norway Regional Health Authority

Background

Reduced left atrial (LA) reservoir strain is a marker of elevated LA pressure. Thus it could be a potential non-invasive marker to differentiate pre- and post-capillary pulmonary hypertension (PH) as the latter is defined by elevated pulmonary capillary wedge pressure (PCWP) &gt; 15 mmHg. However, in pre-capillary PH patients with elevated right atrial pressure (RAP), the atrial septal geometry may be abnormal. This could lead to lower regional LA septal strain, making LA lateral wall strain more accurately reflect PCWP.

Purpose

We investigated if LA lateral wall strain can differentiate between pre- and post-capillary PH, and how LA lateral wall strain and LA septal strain are both affected by elevated RAP in pre-capillary PH. Furthermore we investigated if LA septal strain can be used in pre-capillary PH patients to identify those with elevated RAP.

Methods

We analysed 63 patients with PH, 28 pre-capillary and 35 post-capillary, who underwent right heart catheterisation. Echocardiography was performed simultaneously with or within 24 hours of the invasive pressure measurements. Regional LA septal strain and lateral wall strain were measured from the apical four chamber view.

Results

Pulmonary artery pressure was 39.5 ± 11.1 mmHg (mean ± SD) in the pre-capillary PH patients and 37.0 ± 10.1 mmHg in the post-capillary PH patients (p = ns). Mean PCWP was 9.9 ± 2.5 mmHg and 24.5 ± 6.0 mmHg (p &lt; 0.001), respectively.

LA lateral wall strain was significantly lower in patients with post-capillary PH compared to pre-capillary PH (11.9 ± 7.7% vs 26.6 ± 9.9%, p &lt; 0.001) (Fig. a,b). At a cut-off value of 18.0%, LA lateral wall strain could predict elevated PCWP &gt; 15 mmHg with AUC = 0.88, sensitivity = 85.7% and specificity = 76.3%.

In the 28 patients with pre-capillary PH, we classified mean RAP ≥ 10 mmHg as elevated and &lt; 10 mmHg as normal. Seven of these patients had elevated RAP and showed significantly reduced LA septal strain compared to the 21 patients with normal RAP (13.0 ± 6.2% vs 22.1 ± 7.6%, p &lt; 0.01). LA lateral wall strain showed no difference in these groups of pre-capillary PH patients (25.8 ± 10.1% vs 28.9 ± 9.4%) (Fig. c).

Conclusions

LA lateral wall strain can be used for differentiating between pre- and post-capillary PH. In addition, LA septal strain may be used in pre-capillary PH patients to identify those with elevated RAP.

Abstract 1231 Figure

Long-term continuous flow mechanical biventricular support: 9 years and counting

We report 2 continuous flow HeartWareTM left ventricular assist devices successfully used in a patient with advanced heart failure of giant cell myocarditis origin in a biventricular configuration. Despite technical challenges of adapting a left ventricular assist device engineered for systemic pressure to function as a right ventricular assist device, the addition of dynamic banding on the right ventricular assist device outflow graft allowed successful adaptation of afterload. This patient has now been on biventricular configuration support for 9 years, and remains stable to this day.

P4368Estimation of pulmonary artery pressure from right atrial strain and tricuspid regurgitation velocity

Background

Systolic pulmonary artery pressure (SPAP) can be estimated non-invasively as the sum of indices for right atrial (RA) pressure and tricuspid regurgitation (TR) pressure gradient. Although echocardiographic evaluation of inferior vena cava diameter and collapsibility is currently being used to estimate RA pressure (IVC method), RA strain may be an alternative since atrial strain is related to atrial pressure.

Objective

We tested if RA strain by speckle tracking echocardiography can be used as a surrogate of mean RA pressure (RA strain method), and by adding the TR pressure gradient, be used to estimate SPAP.

Methods

We retrospectively analyzed 91 patients (mean age, 58 years) referred to right heart catheterization due to unexplained dyspnea or suspected pulmonary hypertension. Echocardiography was performed within 24 hours of the invasive procedure. RA reservoir strain was calculated from apical four-chamber view. SPAP was calculated as the sum of peak TR pressure gradient and estimated RA pressure by the IVC or RA strain methods.

Results

Right heart catheterization showed SPAP and mean RA pressures of 51±20 mmHg and 9±6 mmHg, respectively. RA reservoir strain was inversely correlated with mean RA pressure (r=−0.61, p<0.01). Thus, we set mean RA pressure as 5, 10 and 15 mmHg depending on high (≥25%), middle (10–25%) and low (≤10%) values of RA reservoir strain. As shown in the figure, both the RA strain and IVC methods when combined with peak TR velocity, provided good estimates of invasively measured SPAP.

Conclusions

RA strain provides a semiquantitative measure of RA pressure, which can be used in combination with peak TR velocity to estimate SPAP. This approach can be used as an alternative when the IVC method is not available in cases with poor subcostal window.

P2452Application of left atrial strain for differentiation between pre- and post-capillary pulmonary hypertension

Background

Pulmonary hypertension (PH) is classified as pre- or post-capillary PH, and pulmonary capillary wedge pressure (PCWP) >15 mmHg is used as criterion for post-capillary PH. Elevated left atrial (LA) pressure is associated with reduced LA reservoir strain. Thus, LA strain may potentially serve to differentiate between these diagnoses.

Objectives

This study tested the hypothesis that LA strain can be used as a noninvasive parameter to differentiate between pre- and post-capillary PH.

Methods

We analyzed 103 patients (mean age: 58 years, 51 female) referred to right heart catheterization due to unexplained dyspnea or suspected heart failure. Echocardiography was performed within 24 hours of the invasive procedure. Mean pulmonary artery pressure (PAP) was noninvasively estimated from tricuspid regurgitation (TR) velocity and inferior vena cava (IVC) diameter and collapsibility. LA reservoir strain was calculated from apical four-chamber view by speckle tracking echocardiography, and was feasible in 101 patients.

Results

Twenty-eight patients were invasively confirmed with pre-capillary PH and 43 patients with post-capillary PH. The remaining 32 patients had no PH. LA reservoir strain was significantly lower in patients with post-capillary PH than patients with pre-capillary PH (9.9±5.5% vs. 24.6±8.2%, p<0.01). At a cut-off value of 15.4%, LA reservoir strain could predict elevated PCWP >15 mmHg with AUC=0.88, sensitivity=84.8% and specificity=81.8%. As shown in the figure, echocardiography with LA reservoir strain correctly differentiated 82% of patients into pre- and post-capillary PH.

Conclusions

These results suggest that LA reservoir strain can be used to predict elevated PCWP, thus allowing discrimination between pre- and post-capillary PH.

P1480Left atrial strain improves estimation of left ventricular filling pressure

Background

The current algorithm in the 2016 recommendations for echocardiographic estimation of left ventricular filling pressure (LVFP) as normal or elevated, combines traditional indices of mitral inflow velocities, tissue Doppler, left atrial volume and tricuspid regurgitation velocity (Figure A). Some of the patients remain unclassified by this algorithm. Left atrial (LA) strain is a novel index that correlates well with LVFP and may improve estimation of LVFP in these patients.

Purpose

We tested if LA strain can improve estimation of LVFP for the patients that are unclassified by the 2016 algorithm.

Methods

We analyzed data from 100 patients who were referred to right heart catheterization due to unexplained dyspnea or suspected heart failure. Echocardiography was performed simultaneously with or within 24 hours of right heart catheterization. Pulmonary capillary wedge pressure (PCWP) was used as an estimate for LVFP and defined as elevated if above 12 mmHg. Elevated LVFP was first estimated using the 2016 algorithm. In patients who were unclassified by the algorithm due to conflicting indices or unattainable indices, LA strain was subsequently used to detect elevated LVFP using a cut-off found from ROC analysis of the whole cohort.

Results

Six patients were unclassified by the 2016 algorithm. The ROC analysis of all 100 patients showed that at an LA strain cut-off of above or below 16.2%, LVFP was correctly classified as normal or elevated, respectively, with a sensitivity of 83% and specificity of 88%. All 6 unclassified patients by the 2016 algorithm were correctly classified using the LA strain cut-off, effectively increasing the accuracy of the algorithm by 6 percentage points.

Conclusions

LA strain may have a role in non-invasive estimation of LVFP, particularly in patients who remain unclassified when using the conventional echocardiographic indices.

Acknowledgement/Funding

South-Eastern Norway Regional Health Authority

P2458Restricted left atrial motion as a result of atrial stiffening in patients with cardiac amyloidosis

Background

Left atrial (LA) involvement of abnormal amyloid fibrils could induce LA dysfunction and stiffening in patients with cardiac amyloidosis (CA). Thus, the assessments of LA function and stiffness might be a potential approach to diagnose CA phenotype among patients with hypertrophied hearts.

Purpose

We sought to determine whether LA reservoir strain with speckle tracking echocardiography could be used a marker of LA stiffness in a derivation cohort. Furthermore, we tested to our hypothesis that LA reservoir strain could differentiate CA patients from hypertrophic cardiomyopathy (HCM) in an independent validation cohort.

Methods

In the derivation cohort, echocardiography was performed simultaneously with measurements of pulmonary capillary wedge pressure (PCWP) in 50 patients with suspected or established heart failure and relatively preserved left ventricular (LV) ejection fraction (56±10%). LA maximum and minimum volume index, and reservoir strain were measured from apical four-chamber view. LA stiffness index was computed as a pressure rise from x-trough to v-wave divided by an increase from minimum to maximum indexed LA volume (Figure A). In an independent validation group, we studied a total of 33 biopsy-proved CA patients and 127 HCM patients (LV ejection fraction: 57±11% vs. 66±10%, P<0.01) in sinus rhythm on the date of comprehensive echocardiographic study. Among them, cardiac magnetic resonance imaging (CMR) could be evaluated in 17 CA patients and 98 HCM patients. Furthermore, right heart catheterization was performed with 12 CA patients and 12 HCM patients in the CMR group.

Results

The derivation cohort study found that there was a significant curvilinear correlation of LA reservoir strain to LA stiffness index (Figure B). In the validation cohort, LA reservoir strain was reduced in patients with CA compared with HCM in all participants (11.6±5.6% vs. 18.5±6.9%, P<0.01), although there was no significant difference of LA maximal volume index between 2 groups (37±16 ml/m2 vs. 37±12 ml/m2, p=0.89). In the CMR group, the late gadolinium enhancement was observed in the LA wall in 16 patients with CA (94.1%) as shown in Figure C. In contrast, the LA enhancement revealed only in 1 patient with HCM (1.0%). Among patients with invasive measures, LA stiffness index [median (interquartile range)] was higher in patients with CA than that in patients with HCM [1.1 (0.4–2.8) vs. 0.2 (0.1–0.6), P=0.01].

Conclusions

LA reservoir function was fairly limited in patients with CA compared with HCM. Restricted LA motion might be related to atrial amyloid deposits or fibrosis, which potentially provokes atrial chamber stiffening.

Left Ventricular Diastolic Dysfunction Predicts Mortality in Patients With Systemic Sclerosis

BACKGROUND

Primary cardiac affection is common and is a major cause of death in systemic sclerosis (SSc), but there are knowledge gaps regarding the effect of cardiac dysfunction on mortality.

OBJECTIVES

The purpose of this study was to evaluate diastolic function in a large, unselected SSc cohort and assess the effect of diastolic dysfunction (DD) on mortality.

METHODS

SSc patients followed prospectively at the Oslo University Hospital from 2003 to 2016 with available echocardiographies and matched control subjects were included. DD was assessed by echocardiography according to the 2016 American Society of Echocardiography/European Association of Cardiovascular Imaging guidelines. Pulmonary hypertension (PH) was diagnosed by right heart catheterization. Vital status was available for all patients. Cox regression analyses with hazards ratios (HRs) were conducted.

RESULTS

Diastolic function was assessed in 275 SSc patients at baseline and in 186 patients at follow-up. At baseline, 46 of the 275 SSc patients (17%) were diagnosed with DD and 195 (71%) had normal diastolic function. After a median follow-up of 3.4 years (interquartile range: 1.6 to 6.2 years), the proportion of DD increased from 17% to 29%. During follow-up, 57% of patients with DD at baseline died, compared with 13% of patients with normal diastolic function. At baseline, 86 patients had performed right heart catheterization, and 43 were diagnosed with PH; of these 60% deceased. In multivariable Cox regression analyses, DD was a stronger predictor of death (HR: 3.7; 95% CI: 1.69 to 8.14; c-index 0.89) than PH (HR: 2.0; 95% CI: 1.1 to 3.9; c-index 0.84).

CONCLUSIONS

DD is frequent in SSc, and the presence of DD is associated with high mortality. DD exceeds PH with respect to predicting mortality.

Intra-aortic balloon pump in acute chest pain and cardiogenic shock - a long-term follow-up

Objectives. Coronary revascularisation and intra-aortic balloon pump (IABP) has been considered the gold standard treatment of acute coronary syndrome with cardiogenic shock, recently challenged by the SHOCK II study. The aim of this non-randomised study was to investigate the long term prognosis after immediate IABP supported angiography, in patients with acute chest pain and cardiogenic shock, treated with percutaneous coronary intervention (PCI), cardiac surgery or optimal medical treatment. We assessed data from 281 consecutive patients admitted to our department from 2004 to 2010. Results. Mean (±SD) age was 63.8 ± 11.5 (range 30-84) years with a follow-up of 5.6 ± 4.4 (0-12.7) years. Acute myocardial infarction was the primary diagnosis in 93% of the patients, 4% presented with unstable angina pectoris and 3% cardiomyopathy or arrhythmias of non-ischemic aetiology. Systolic blood pressure at admittance was 85 ± 18 mmHg and diastolic 55 ± 18 mmHg. Thirty day, one- and five-year survival was 71.2%, 67.3% and 57.7%, respectively. PCI was performed immediately in 70%, surgery was done in 17%, and 13% were not eligible for any revascularisation. Independent variables predicting mortality were medical treatment vs revascularisation, out-of-hospital cardiac arrest, and advanced age. Three serious non-fatal complications occurred due to IABP treatment, i.e. 0.001 per treatment day. Conclusions. We report the use of IABP in patients with acute chest pain admitted for angiography. Long-term survival is acceptable and discriminating factors were no revascularisation, out-of-hospital cardiac arrest and age. IABP was safe and feasible and the complication rate was low.

Effect of Everolimus Initiation and Calcineurin Inhibitor Elimination on Cardiac Allograft Vasculopathy in De Novo Heart Transplant Recipients

Background Cardiac allograft vasculopathy (CAV) limits survival after heart transplantation, and the effect of different immunosuppressive regimens on CAV is not fully understood. The randomized SCHEDULE trial (Scandinavian Heart Transplant Everolimus De Novo Study With Early Calcineurin Inhibitors Avoidance) evaluated whether initiation of the proliferation signal inhibitor everolimus and early cyclosporine elimination can reduce CAV development. Methods and Results The SCHEDULE trial was a multicenter Scandinavian trial, where 115 de novo heart transplantation recipients were randomized to everolimus with complete cyclosporine withdrawal 7 to 11 weeks after heart transplantation or standard cyclosporine-based immunosuppression. Seventy-six (66%) patients had matched intravascular ultrasound examinations at baseline and 12 and 36 months. Intravascular ultrasound analysis evaluated maximal intimal thickness, percent atheroma volume, and total atheroma volume. Qualitative plaque analysis using virtual histology assessed fibrous, fibrofatty, and calcified tissue as well as necrotic core. Serum inflammatory markers were measured in parallel. The everolimus group (n=37) demonstrated significantly reduced CAV progression as compared with the cyclosporine group (n=39) at 36 months (Δ maximal intimal thickness, 0.09±0.05 versus 0.15±0.16 mm [ P=0.03]; Δ percent atheroma volume, 5.3±2.8% versus 7.6±5.9% [ P=0.03]; and Δ total atheroma volume, 33.9±71.2 versus 54.2±96.0 mm³ [ P=0.34], respectively]. At 36 months the number of everolimus patients with rejection graded ≥2R was 15 (41%) as compared with 5 (13%) in the cyclosporine group ( P=0.01). Everolimus did not affect CAV morphology or immune marker activity during the follow-up period. Conclusions The SCHEDULE trial demonstrates that everolimus initiation and early cyclosporine elimination significantly reduces CAV progression at 12 months, and this beneficial effect is clearly sustained at 36 months. Clinical trial registration URL: https://www.clinicaltrials.gov . Unique identifier: NCT01266148.

The carnitine-butyrobetaine-TMAO pathway after cardiac transplant: Impact on cardiac allograft vasculopathy and acute rejection

BACKGROUND

Alterations in the partly microbiota-dependent carnitine-γ-butyrobetaine (γBB)-trimethylamine N-oxide (TMAO) pathway have been linked to the progression of heart failure and atherosclerotic disease. We evaluated if circulating γBB, TMAO, and their common precursors carnitine and trimethyllysine (TML) were dysregulated after heart transplantation and associated with development of cardiac allograft vasculopathy (CAV) and acute rejection.

METHODS

We measured these metabolites in plasma from heart transplant recipients with everolimus-based (n = 32) and standard cyclosporine-based immunosuppression (n = 30) at different time-points and accompanied by assessment of CAV by intravascular ultrasound.

RESULTS

Baseline levels of carnitine, TMAO, and TML were elevated in heart transplant recipients compared with controls, and TML remained elevated throughout the observation period. The microbiota-dependent metabolite γBB increased steadily during 3 years of follow-up, with a similar decrease in its endogenous precursor TML. The increase in γBB and the change in TML were associated with a change in total atheroma volume from baseline to 3 years. Increases in γBB and carnitine levels from baseline to 1 year were associated with an increased frequency of acute rejection within the first year after heart transplant.

CONCLUSIONS

Our study reveals alterations of the carnitine-γBB-TMAO pathway after heart transplant, with increasing levels of γBB being associated with acute rejection and increase in total atheroma volume during 3 years of follow-up. Future studies should clarify whether interactions between dietary factors, immunosuppressive drugs, and the gut microbiota could influence acute rejection and CAV development to delineate mechanisms and potential novel treatment targets.