Mechanical contraction patterns of the systemic right ventricle: a 3D echocardiography study

Funding Acknowledgements

Type of funding sources: None.

Background. In patients with transposition of great arteries (TGA) post atrial switch operation or with congenitally corrected TGA (ccTGA), the morphologically right ventricle (RV) has to adapt to the chronically increased systemic pressure.

Purpose. To investigate the functional adaptation of the systemic RV in patients with TGA post Mustard repair or ccTGA. 

Methods. RV volumes and EF were measured by 3D echocardiography in 33 patients with the systemic RV (21 TGA and 12 ccTGA; 45 ± 13y, 61% male), and in 33 healthy volunteers (44 ± 13y, 61% male). 

The 3D RV model was postprocessed by the ReVISION software and its contraction was decomposed along the longitudinal, radial and anteroposterior directions (Fig.A, Systemic RV in TGA) providing longitudinal, radial and anteroposterior EF (LEF, REF and AEF). Relative contribution of each component was measured as the ratio between LEF, REF and AEF to the global RVEF (LEFi, REFi and AEFi).

Results. Systemic RV was significantly larger with reduced function compared to controls (Tab). 3D RVEF demonstrated stronger correlation with BNP (Rho -0.76, p < 0.0001) compared to other parameters of RV function (free wall strain 0.55, p = 0.0083; FAC -0.47, p = 0.024; S’ -0.39 and TAPSE 0.06, p > 0.05).

While in healthy volunteers, all 3 components of RV systolic function contributed equally to the global RV EF, in patients with TGA the relative contribution of the anteroposterior component was dominant and differed significantly from longitudinal and radial components (AEFi 0.48 ± 0.06 vs LEFi 0.31 ± 0.07 vs REFi 0.36 ± 0.09, p < 0.0001)(Fig. B,C). In patients with ccTGA the longitudinal component was dominant and provided a relative compensation for the reduced anteroposterior and radial components (LEFi 0.47 ± 0.07 vs AEFi 0.34 ± 0.07, p = 0.0002 and vs REFi 0.36 ± 0.09, p = 0.0023)(Fig. B,C). Relative contribution of the radial contraction was significantly reduced in all systemic RV patients.

Conclusions. Systemic RV contraction patterns change significantly with anteroposterior contraction being dominant in patients with TGA post Mustard repair and longitudinal component being dominant in ccTGA.

3DE should be a part of routine assessment of the systemic RV, especially in TGA since no conventional echo parameters take into account anteroposterior RV contraction.

Parameters of RV systolic function Parameter Control group (N = 33) All SRV patients (N = 33) TGA (N = 21) ccTGA (N = 12) 3D EF, % 60 ± 3.8 36 ± 8.6* 34 ± 7.3* 38 ± 10* FAC, % 41.4 ± 3.7 25.9 ± 9.3* 25.1 ± 9.2* 27.1 ± 9.9* TAPSE, mm 24.6 ± 4.2 11.9 ± 3.9* 11.1 ± 2.9* 13.2 ± 5.1* RV free wall strain, % -32.5 ± 4.2 -14.5 ± 3.5* -14.5 ± 2.9* -15.5 ± 3.5* * p < 0.0001 Abstract Figure.

Anaemia and coronary microvascular dysfunction in end-stage renal disease

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): (1) University Hospitals Birmingham Charity (2) Metchley Park Medical Society

Introduction

 

Coronary microvascular dysfunction (CMD) is common among patients with end-stage renal disease (ESRD) and confers poor prognosis. Coronary flow velocity reserve (CFVR) is a marker of coronary microvascular function and can be reliably measured using Doppler echocardiography. Reduced CFVR in ESRD has been attributed to factors such as hypertension and left ventricular hypertrophy (LVH). Anaemia is prevalent in ESRD but the association between haemoglobin and CFVR in ESRD has not been studied. 

Purpose

 

To assess if CFVR is related to haemoglobin among patients with ESRD. 

Methods

 

22 subjects with ESRD and awaiting kidney transplant (8 pre-dialysis and 14 on peritoneal dialysis) were studied with adenosine myocardial contrast echocardiography, Doppler CFVR assessment and serum multiplex immunoassay analysis. Individuals with diabetes, uncontrolled hypertension or ischaemic heart disease were excluded.

Results 

7/22 (32%) of subjects had CMD (defined as CFVR <2). Age (47 years ± 15 vs 55 ± 10, p = 0.177), estimated glomerular filtration rate [7ml/min/1.73m² (5-11) vs 9 (7-10), p = 0.837], systolic blood pressure (129mmHg ± 25 vs 137 ± 20, p = 0.398) and left ventricular mass index (98g/m² ± 31 vs 98 ± 28, p = 0.936) did not significantly differ between subjects with or without CMD. There were no significant differences in other demographic, haemodynamic, laboratory or echocardiographic variables between the two groups.  A panel of biomarkers of inflammation, myocardial stretch, cardiac fibrosis and LVH studied by multiplex immunoassay also did not show any significant differences between the two groups. No subjects had wall motion abnormalities or perfusion defects on myocardial contrast echocardiography.

CFVR was significantly lower in subjects with CMD (1.6 ± 0.2 vs 3.2 ± 0.9, p < 0.001). Subjects with CMD had significantly lower haemoglobin than subjects without CMD (102g/L ± 12 vs 117g/L ± 11, p = 0.008). There was a moderate positive correlation between haemoglobin and CFVR (r = 0.65, p = 0.001) – figure 1. In a stepwise multiple regression model with CFVR as the dependent variable and age, haemoglobin, systolic blood pressure, left ventricular mass index and estimated glomerular filtration rate as independent variables, only haemoglobin was an independent predictor of CFVR (β=0.051 95%CI 0.023-0.079, p = 0.001). 

Conclusions 

Among our cohort of ESRD patients awaiting kidney transplant, there was a high prevalence of CMD despite well controlled blood pressure and no significant LVH. Subjects with CMD had significantly lower haemoglobin than subjects without CMD. Reduced haemoglobin causes impaired oxygen carrying capacity to the myocardium, which may lead to microvascular ischaemia and adverse microvascular remodelling, causing CMD. Thus, anaemia may be a potentially correctible driver of CMD in ESRD.  This association needs to be confirmed in larger studies.

Abstract Figure 1

Clinical value of stress transaortic flow rate during dobutamine echocardiography in low-gradient aortic stenosis

Funding Acknowledgements

Type of funding sources: None.

BACKGROUND/INTRODUCTION

The clinical value of rest transaortic flow rate (FR) has been shown previously in low-gradient aortic stenosis (LGAS) for the prediction of outcome. However limited data exists on the prognostic value of stress FR in LGAS following low-dose dobutamine stress echocardiography (LDDSE).

PURPOSE

We aimed to assess the value of stress FR in patients with LGAS in the diagnosis of AS severity and the prediction of mortality.

METHODS

This is a multi-centre cohort study of patients with low left ventricular ejection fraction (LVEF) and LGAS (aortic valve area –AVA <1cm²) who underwent LDDSE.

RESULTS

Of the 287 patients (mean age:  75.1 ±10 years, males: 71%) over the mean follow-up of 24 ±30 months there were 127 (44.3%) deaths and 147 (51.2%) patients underwent aortic valve intervention. Lower stress FR was independently associated with increased risk of mortality (HR= 0.99, 95%CI= 0.99-0.999, p= 0.02) after adjusting for age, chronic kidney disease, presence of symptoms (NYHA II-IV), aortic valve intervention, rest LVEF and guideline-defined severe AS (AV mean gradient- AVMG ≥40mmHg with AVA <1cm² at peak stress).  The minimum cut-off for prediction of mortality was stress FR 210ml/sec. Among the different criteria of AS severity during stress, i.e. guideline-defined criterion, or stress AVMG ≥40mmHg, or stress AVA <1cm² at stress FR ≥210ml/s, only the latter was independently associated with mortality (HR= 1.81, 95%CI= 1.04-3.2, p= 0.04) (Table 1) and was the parameter of AS severity that predicted improved outcome following aortic valve intervention (p <0.005) (Figure 1). Guideline-defined stroke volume flow reserve did not predict mortality.

CONCLUSIONS

Assessment of stress FR during LDDSE is important for the detection of both AS severity and flow reserve.

Table 1 Multivariable analysis for prediction of all-cause mortality (N = 287) for the different criteria of aortic stenosis HR 95%CI p Age 1 0.98-1.03 0.84 Chronic kidney disease 1..84 1.13-2.99 0.01 Aortic valve intervention 0.37 0.22-0.61 <0.005 Presence of symptoms (NYHA II-IV) 1.87 0.66-5.31 0.24 Rest LVEF (by 1%) increase 0.97 0.95-1 0.06 Stress AVA < 1cm² with stress AVMG≥40mmHg 1.02 0.31-3.34 0.97 Stress AVMG≥40mmHg 0.57 0.2-1.59 0.28 Stress AVA < 1cm² at stress FR≥210mmHg 1.81 1.04-3.2 0.04 Abstract Figure 1

Systolic dysfunction of the subpulmonary left ventricle is associated with the severity of heart failure in patients with a systemic right ventricle

BACKGROUND

The study aimed to assess the relation between echocardiographic parameters of subpulmonary left ventricular (LV) size and function, and the severity of heart failure in patients with a systemic right ventricle (SRV).

METHODS AND RESULTS

A total of 157 patients (89 post Mustard/Senning operations, 68 with congenitally corrected transposition of great arteries [ccTGA]) were included. The size and function of the SRV and subpulmonary LV were assessed on the most recent echocardiographic exam. Clinical data were collected from the electronic records. The majority (133, 84.7%) were in NYHA functional class 1-2. Median BNP concentration was 79.5[38.3-173.3] ng/l, and 100 (63.7%) patients were receiving heart failure therapy. Both LV and SRV fractional area change (FAC) differed significantly between patients with NYHA class 1-2 vs 3-4 (48[41.5-52.8]% vs 34[28.6-38.6]%, p < 0.0001 and 29.5[23-35]% vs 22[20-27]%, p < 0.0001, respectively), but LV FAC had a higher discriminative power for functional class >2 than SRV FAC (AUC 0.90, p < 0.0001 vs 0.79; p < 0.0001, respectively). A LV FAC cut-off value <39.2% had the highest accuracy in identifying patients with NYHA class 3-4 (sensitivity 83% and specificity 88%). In multivariable logistic regression analysis, LV FAC and SRV FAC independently associated to NYHA class 3-4 (OR 0.80 [95%CI 0.72-0.88], p < 0.0001 and OR 0.85 [95%CI 0.76-0.96], p = 0.007, respectively).

CONCLUSIONS

Subpulmonary LV systolic dysfunction is associated with NYHA functional class 3-4 in patients with ccTGA or after Mustard or Senning operation. Careful evaluation of the subpulmonary LV should be a part of the routine assessment of patients with a SRV.

Aortic intervention guided by contrast-enhanced transoesophageal ultrasound whist waiting for cardiac transplantation: a case report

Background 

Aortic complications can happen during left ventricular assist devices (LVADs) insertion and its treatment remains challenging. Percutaneous aortic interventions can be an alternative to surgery in such high-risk cases.

Case summary 

We present a patient with idiopatic dilated cardiomyopathy and advanced heart failure requiring LVAD insertion as a bridge to transplant, who developed an aortic pseudoaneurysm below the anastomosis of the LVAD tube. He was successfully treated with percutaneous coiling under contrast-enhanced transoesophageal echocardiography (TOE) guidance, reaching destination therapy (heart transplantation) a year later.

Discussion 

Left ventricular assist devices provide haemodynamic support for patients with advanced heart failure waiting for heart transplantation. Although uncommon, aortic complications can happen as a result of LVAD insertion and be life-threatening. Percutaneous aortic interventions can be performed in such cases to promote thrombosis and remodelling of false lumen or aneurysmatic spaces, hence potentially reducing the risk of sudden death. Contrast-enhanced TOE can be easily and safely used to monitor the intervention in order to improve anatomic definition, guide positioning of wires and catheters and assess early results.

Relative clinical value of coronary computed tomography and stress echocardiography-guided management of stable chest pain patients: a propensity-matched analysis

AIMS

The European Society of Cardiology recommends coronary computed tomography (CCT) for the assessment of low-risk patients with suspected stable angina. We aimed to assess in a real-life setting the relative clinical value of stress echocardiography (SE)- and CCT-guided management in this population.

METHODS AND RESULTS

Patients with stable chest pain and no prior history of coronary artery disease (CAD) who underwent CCT or SE as the initial investigative strategy were propensity-matched (990 patients each group-age: 59 ± 13.2 years, males: 47.9%) to account for baseline differences in cardiovascular risk factors. Inconclusive tests were 6% vs. 3% (P < 0.005) in CCT vs. SE. Severe (≥70% stenosis) on CCT and inducible ischaemia on SE detected obstructive CAD by invasive coronary angiography in 63% vs. 57% patients (P = 0.33). Over the follow-up period (median 717, interquartile range 93-1069 days) more patients underwent invasive coronary angiography (21.5% vs. 7.3%, P < 0.005), revascularization (7.3% vs. 3.5%, P < 0.005), further functional testing 33.4% vs. 8.7% (P < 0.005), but more patients were prescribed statins 8.8% vs. 3.8% (P < 0.005) in the CCT vs. the SE arm, respectively. Combined all-cause mortality and acute myocardial infarction was low-CCT-2.3% and SE-3.3%-with no significant difference (P = 0.16).

CONCLUSION

Initial SE-guided management was similar for the detection of obstructive CAD, demonstrated better resource utilization, but was associated with reduced prescription of statins although with no difference in medium-term outcome compared to CCT in this very low-risk population. However, a randomized study with longer follow-up is needed to confirm the clinical value of our findings.

Right ventricular dysfunction in critically ill COVID-19 ARDS

Aims

Comprehensive echocardiography assessment of right ventricular (RV) impairment has not been reported in critically ill patients with COVID-19. We detail the specific phenotype and clinical associations of RV impairment in COVID-19 acute respiratory distress syndrome (ARDS).

Methods

Transthoracic echocardiography (TTE) measures of RV function were collected in critically unwell patients for associations with clinical, ventilatory and laboratory data.

Results

Ninety patients (25.6% female), mean age 52.0 ± 10.8 years, veno-venous extracorporeal membrane oxygenation (VVECMO) (42.2%) were studied. A significantly higher proportion of patients were identified as having RV dysfunction by RV fractional area change (FAC) (72.0%,95% confidence interval (CI) 61.0–81.0) and RV velocity time integral (VTI) (86.4%, 95 CI 77.3–93.2) than by tricuspid annular plane systolic excursion (TAPSE) (23.8%, 95 CI 16.0–33.9), RVS’ (11.9%, 95% CI 6.6–20.5) or RV free wall strain (FWS) (35.3%, 95% CI 23.6–49.0). RV VTI correlated strongly with RV FAC (p ≤ 0.01). Multivariate regression demonstrated independent associations of RV FAC with NTpro-BNP and PVR. RV-PA coupling correlated with PVR (univariate p < 0.01), as well as RVEDAi (p < 0.01), and RVESAi (p < 0.01), and was associated with P/F ratio (p 0.026), PEEP (p 0.025), and ALT (p 0.028).

Conclusions

Severe COVID-19 ARDS is associated with a specific phenotype of RV radial impairment with sparing of longitudinal function. Clinicians should avoid interpretation of RV health purely on long-axis parameters in these patients. RV-PA coupling potentially provides important additional information above standard measures of RV performance in this cohort.

Coronary computed tomography versus stress echocardiography-guided management of stable chest pain patients: a propensity matched analysis

Background

Recent recommendations by national and international societies advocate the use of coronary computed tomography (CCT) as the first-line test for the assessment of low-risk patients with suspected stable angina. However limited real-life data exist regarding its relative clinical value versus stress echocardiography (SE)-guided management.

Purpose

We aimed to assess in a real-life setting the clinical value of stress echocardiography (SE)-guided versus CCT-guided management in patients presenting with stable chest pain and no prior history of coronary artery disease (CAD).

Methods

We compared the relative feasibility, efficacy and the proportion of patients undergoing downstream testing including revascularisation and their impact on outcome (mortality and myocardial infarction) when CCT versus SE were used as the first line test for the assessment of stable chest pain.

Of the patients who underwent CCT (N=2192) or SE (N=2081) between October 2013 and October 2014 only those with suspected stable angina and without previous CAD were selected. The population was propensity-matched (total 1980 patients-990 patients each group) to account for differences in the baseline cardiovascular risk factors.

Results

The mean age of the population was 59±13.2 years and 949 (47.9%) patients were male. Inconclusive tests were 6% versus 3% (p&lt;0.005) in CCT versus SE. Severe (&gt;70%) luminal stenosis on CCT and inducible ischemia on SE detected obstructive CAD by invasive coronary angiography in 63% versus 57% patients (p=0.33). Over the entire follow-up period (median 717 (IQR 93–1069) days) significantly more patients underwent invasive coronary angiography (21.5% versus 7.3%, p&lt;0.005) and revascularisation (33.5% versus 3.5%, p&lt;0.005) respectively in the CCT versus the SE group. Following their initial assessment 336 (33.9%) patients in the CCT and 86 (8.7%) in the SE group underwent further functional testing (SE, stress cardiac MRI, exercise electrocardiography) (p&lt;0.005) (Figure 1A). There was no difference in all-cause mortality (p=0.26) or death and myocardial infarction (p=0.16) between the two groups (Figure 1B).

Conclusions

SE when used for the assessment of patients with stable angina and no prior CAD resulted in more conclusive tests, similar detection of obstructive CAD, less overall invasive coronary angiography and revascularization and less subsequent functional tests compared with CCT.

Figure 1

Funding Acknowledgement

Type of funding source: None

Demographic characteristics, aortic valve intervention rates and all-cause mortality in 4 flow-gradient sub-types of severe aortic stenosis

Introduction

Severe aortic stenosis (AS), defined as aortic valve area (AVA) &lt;1.0 cm2, can be divided into 4 categories based on flow status and mean gradient. Stroke volume index &lt;35 ml/m2 has classically been used to define low flow, but recent data suggest that flow rate (FR) &lt;200ml/sec may be a more accurate and robust marker of low flow.

Methods

We prospectively collected demographic, echocardiographic, aortic valve intervention (AVI) and all-cause mortality data on 1562 patients with symptomatic severe AS from 2010 to 2017 with a mean follow up period of 35±22 months. Patients were divided into 4 flow-gradient sub-groups based on a FR threshold of 200ml/s and mean pressure gradient of 40mmHg. Comparative analyses were performed among the 4 groups using analysis of variance.

Results

The prevalence of normal flow high gradient (NFHG) severe AS was 30%, NF low gradient (NFLG) 21%, low flow HG (LFHG) 18% and LFLG 31% (Table). Across these 4 sub-groups, there was a graded reduction in LVEF and FR, and an increase in age and all–cause mortality.

Conclusions

Classification of aortic stenosis based on flow-gradient patterns, shows important differences in the demographic profile and clinical outcome among the 4 groups. Classical NFHG AS was associated with the highest rate of AVI and lowest all-cause mortality compared to the 3 discordant flow-gradient subtypes. The LFLG group had the lowest AVI rates and worst outcome.

Funding Acknowledgement

Type of funding source: None

Reversible exercise-induced left ventricular dysfunction in symptomatic patients with previous Takotsubo syndrome: insights from stress echocardiography

AIMS

Takotsubo syndrome (TTS) is usually associated with rapid and spontaneous recovery of left ventricular (LV) function. However, a proportion of patients may have persistent symptoms. This study aimed to determine the haemodynamic and LV contractile responses to exercise in these patients.

METHODS AND RESULTS

Thirty symptomatic TTS patients referred for exercise echocardiography, a median of 15 months following the index TTS episode, were matched with 30 controls with normal exercise echocardiography. Beta-blockers were withheld prior to the test. LV volumes, ejection fraction (EF) and wall motion score index (WMSI), were measured at rest and stress. The TTS cohort were Caucasian women with mean age of 64.6 ± 7.4 years and similar coronary risk factor profile and EF to controls. Resting systolic blood pressure (SBP), LV end-diastolic volume, wall stress, and right ventricular fractional area change were higher in TTS patients compared with controls. Stress echo data showed similar exercise time, peak heart rate, and peak SBP in TTS patients vs. controls, but TTS patients had higher LV volumes, lower exercise LVEF (70 ± 10% vs. 78 ± 7%; P = 0.001), ΔLVEF (4 ± 8% vs. 12 ± 5%; P < 0.001), and WMSI (1.4 ± 0.4 vs. 1 ± 0; P < 0.001) compared with controls. Twenty TTS patients had clear exercise-induced wall motion abnormalities, mainly involving the apex or more globally, with a mean ΔLVEF of 1% compared with 12% in controls. Among the other 10 TTS patients, the ΔLVEF was 10%.

CONCLUSION

Symptomatic patients with previous TTS have a blunted contractile response to exercise. The therapeutic and prognostic implications of these findings need further investigation.

Coronary flow velocity reserve and inflammatory markers in living kidney donors

BACKGROUND

Coronary microvascular dysfunction is prevalent in chronic kidney disease (CKD), and may contribute to the development of myocardial dysfunction in CKD. Coronary flow velocity reserve (CFVR) is a marker of coronary microvascular function and falls with increasing CKD stage. Living kidney donors have renal function consistent with early stage CKD and concern has been raised about their cardiovascular risk. No studies to date have investigated the presence of coronary microvascular dysfunction in living kidney donors.

METHODS

25 healthy controls and 23 living kidney donors were recruited and underwent assessment with transthoracic echocardiography, Doppler CFVR, myocardial contrast echocardiography and serum multiplex immunoassay panels.

RESULTS

Doppler CFVR was significantly reduced in living kidney donors compared to controls (mean CFVR 3.4 ± 0.7 vs 3.8 ± 0.6, mean difference 0.4 95% confidence interval 0.03-0.8, p =.036). Quantitative myocardial contrast echocardiography showed a trend towards reduced coronary flow reserve in living kidney donors. Compared to controls, living kidney donors had higher serum high sensitivity C reactive peptide (hsCRP) and lower levels of uromodulin.

CONCLUSIONS

This is the first study of CFVR in living kidney donors. We have shown that the modest drop in estimated glomerular filtration rate in living kidney donors is associated with lower values of Doppler CFVR compared to controls, suggesting that isolated reductions in renal function may lead to altered microvascular function. The increase in hsCRP and reduction in uromodulin suggests that chronic subclinical inflammation may contribute to altered microvascular function in this population.

Unexpected mechanism of mitral regurgitation in a patient post ALCAPA repair: Added value of three-dimensional echocardiography

Accurate assessment of etiology of mitral regurgitation (MR) is one of the key steps in the decision-making process and further clinical management of patients with severe MR. Our clinical case illustrates the added value of three-dimensional echocardiography (3DE) in assessment of mitral valve morphology and identification of an unexpected mechanism of MR which was not previously diagnosed using conventional echocardiography. 3DE helped to choose appropriate management strategy in this patient.

Association of Sex With Severity of Coronary Artery Disease, Ischemia, and Symptom Burden in Patients With Moderate or Severe Ischemia: Secondary Analysis of the ISCHEMIA Randomized Clinical Trial

Importance

While many features of stable ischemic heart disease vary by sex, differences in ischemia, coronary anatomy, and symptoms by sex have not been investigated among patients with moderate or severe ischemia. The enrolled ISCHEMIA trial cohort that underwent coronary computed tomographic angiography (CCTA) was required to have obstructive coronary artery disease (CAD) for randomization.

Objective

To describe sex differences in stress testing, CCTA findings, and symptoms in ISCHEMIA trial participants.

Design, Setting, and Participants

This secondary analysis of the multicenter ISCHEMIA randomized clinical trial analyzed baseline characteristics of patients with stable ischemic heart disease. Individuals were enrolled from July 2012 to January 2018 based on local reading of moderate or severe ischemia on a stress test, after which blinded CCTA was performed in most. Core laboratories reviewed stress tests and CCTAs. Participants with no obstructive CAD or with left main CAD of 50% or greater were excluded. Those who met eligibility criteria including CCTA (if performed) were randomized to a routine invasive or a conservative management strategy (N = 5179). Angina was assessed using the Seattle Angina Questionnaire. Analysis began October 1, 2018.

Interventions

CCTA and angina assessment.

Main Outcomes and Measures

Sex differences in stress test, CCTA findings, and symptom severity.

Results

Of 8518 patients enrolled, 6256 (77%) were men. Women were more likely to have no obstructive CAD (<50% stenosis in all vessels on CCTA) (353 of 1022 [34.4%] vs 378 of 3353 [11.3%]). Of individuals who were randomized, women had more angina at baseline than men (median [interquartile range] Seattle Angina Questionnaire Angina Frequency score: 80 [70-100] vs 90 [70-100]). Women had less severe ischemia on stress imaging (383 of 919 [41.7%] vs 1361 of 2972 [45.9%] with severe ischemia; 386 of 919 [42.0%] vs 1215 of 2972 [40.9%] with moderate ischemia; and 150 of 919 [16.4%] vs 394 of 2972 [13.3%] with mild or no ischemia). Ischemia was similar by sex on exercise tolerance testing. Women had less extensive CAD on CCTA (205 of 568 women [36%] vs 1142 of 2418 men [47%] with 3-vessel disease; 184 of 568 women [32%] vs 754 of 2418 men [31%] with 2-vessel disease; and 178 of 568 women [31%] vs 519 of 2418 men [22%] with 1-vessel disease). Female sex was independently associated with greater angina frequency (odds ratio, 1.41; 95% CI, 1.13-1.76).

Conclusions and Relevance

Women in the ISCHEMIA trial had more frequent angina, independent of less extensive CAD, and less severe ischemia than men. These findings reflect inherent sex differences in the complex relationships between angina, atherosclerosis, and ischemia that may have implications for testing and treatment of patients with suspected stable ischemic heart disease.

Trial Registration

ClinicalTrials.gov Identifier: NCT01471522.

Role of adjuvant carotid ultrasound in women undergoing stress echocardiography for the assessment of suspected coronary artery disease

Objective

Due to the low prevalence of obstructive coronary artery disease (CAD) in women, stress testing has a relatively low predictive value for this. Additionally, conventional cardiovascular risk scores underestimate risk in women. This study sought to evaluate the role of atherosclerosis assessment using carotid ultrasound (CU) in women attending for stress echocardiography (SE).

Methods

This was a prospective study in which consecutive women with recent-onset suspected angina, who were referred for clinically indicated SE, underwent CU.

Results

415 women (mean age 61±10 years, 29% diabetes mellitus, mean body mass index 28) attending for SE underwent CU. 47 women (11%) had inducible wall motion abnormalities, and carotid disease (CD) was present in 46% (carotid plaque in 41%, carotid intima-media thickness >75th percentile in 15%). Women with CD were older (65 vs 58 years, p<0.001), and more likely to have diabetes (41% vs 21%, p=0.001), hypertension (67% vs 36%, p<0.01) and a higher pretest probability of CAD (59% vs 41%, p<0.001). 40% of women classified as low Framingham risk were found to have evidence of CD.

The positive predictive value of SE for flow-limiting CAD was 51%, but with the presence of carotid plaque, this was 71% (p<0.01). Carotid plaque (p=0.004) and ischaemia (p=0.01) were the only independent predictors of >70% angiographic stenosis. In women with ischaemia on SE and no carotid plaque, the negative predictive value for flow-limiting disease was 88%.

During a follow-up of 1058±234 days, there were 15 events (defined as all-cause mortality, non-fatal myocardial infarction, heart failure admissions and late coronary revascularisation). Age (HR 1.07 (1.00–1.15), p=0.04), carotid plaque burden (HR 1.65 (1.36–2.00), p<0.001) and ischaemic burden (HR 1.41 (1.18–1.68), p<0.001) were associated with outcome. There was a stepwise increase in events/year from 0.3% when there were no ischaemia and atherosclerosis, 1.1% when there was atherosclerosis and no ischaemia, 2.2% when there was ischaemia and no atherosclerosis and 10% when there were both ischaemia and atherosclerosis (p<0.001).

Conclusion

CU significantly improves the accuracy of SE alone for identifying flow-limiting disease on coronary angiography, and improves risk stratification in women attending for SE, as well identifying a subset of women who may benefit from primary preventative measures.

Sex-based impact of carotid plaque in patients with chest pain undergoing stress echocardiography

OBJECTIVE

Women with suspected angina without history of coronary artery disease (CAD) less frequently have flow-limiting stenosis (FL-CAD) and more often have microvascular disease, affecting predictive accuracy of stress echocardiography (SE) for detection of FL-CAD. We postulated that carotid plaque burden (CPB) assessment would improve detection of FL-CAD and risk stratification.

METHODS

Consecutive consenting patients assessed by SE on clinical grounds for new-onset chest pain also underwent simultaneous carotid ultrasound. Patients were followed for major adverse events (MAE): all-cause mortality, non-fatal myocardial infarction and unplanned revascularisation. Carotid plaque presence and burden (CPB) were assessed.

RESULTS

After a mean of 2617±469 days (range 17-3740), of 591 recruited patients, 573 (97%) outcome data (314 females) were obtainable. Despite lower pretest probability of CAD in females versus males (14.9±0.8 vs 20.5±1.3, respectively, p<0.0001), prevalence of myocardial ischaemia was similar (p=0.08). Females also had lower prevalence of both carotid plaque (p<0.0001) and FL-CAD (p<0.05). CPB improved the positive predictive value of SE for detection of FL-CAD (from 34.5% to 60%) in females but not in males. Absence of CPB in females with myocardial ischaemia ruled out FL-CAD in 93% versus 57% in males. CPB was the only independent predictor of MAE (p=0.012) in females, whereas in males both SE (p<0.0001) and CPB (p=0.003) remained significant.

CONCLUSION

In females with new-onset stable angina without a history of cardiovascular disease, CPB improved the predictive accuracy of myocardial ischaemia for flow-limiting CAD. However, CPB provided incremental risk stratification in both sexes.

Initial Invasive or Conservative Strategy for Stable Coronary Disease

BACKGROUND

Among patients with stable coronary disease and moderate or severe ischemia, whether clinical outcomes are better in those who receive an invasive intervention plus medical therapy than in those who receive medical therapy alone is uncertain.

METHODS

We randomly assigned 5179 patients with moderate or severe ischemia to an initial invasive strategy (angiography and revascularization when feasible) and medical therapy or to an initial conservative strategy of medical therapy alone and angiography if medical therapy failed. The primary outcome was a composite of death from cardiovascular causes, myocardial infarction, or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest. A key secondary outcome was death from cardiovascular causes or myocardial infarction.

RESULTS

Over a median of 3.2 years, 318 primary outcome events occurred in the invasive-strategy group and 352 occurred in the conservative-strategy group. At 6 months, the cumulative event rate was 5.3% in the invasive-strategy group and 3.4% in the conservative-strategy group (difference, 1.9 percentage points; 95% confidence interval [CI], 0.8 to 3.0); at 5 years, the cumulative event rate was 16.4% and 18.2%, respectively (difference, -1.8 percentage points; 95% CI, -4.7 to 1.0). Results were similar with respect to the key secondary outcome. The incidence of the primary outcome was sensitive to the definition of myocardial infarction; a secondary analysis yielded more procedural myocardial infarctions of uncertain clinical importance. There were 145 deaths in the invasive-strategy group and 144 deaths in the conservative-strategy group (hazard ratio, 1.05; 95% CI, 0.83 to 1.32).

CONCLUSIONS

Among patients with stable coronary disease and moderate or severe ischemia, we did not find evidence that an initial invasive strategy, as compared with an initial conservative strategy, reduced the risk of ischemic cardiovascular events or death from any cause over a median of 3.2 years. The trial findings were sensitive to the definition of myocardial infarction that was used. (Funded by the National Heart, Lung, and Blood Institute and others; ISCHEMIA ClinicalTrials.gov number, NCT01471522.).

An Experimental Series Investigating the Effects of Hyperinsulinemic Euglycemia on Myocardial Blood Flow Reserve in Healthy Individuals and on Myocardial Perfusion Defect Size following ST-Segment Elevation Myocardial Infarction

BACKGROUND

Incomplete restoration of myocardial blood flow (MBF) is reported in up to 30% of ST-segment elevation myocardial infarction (STEMI) despite prompt mechanical revascularization. Experimental hyperinsulinemic euglycemia (HE) increases MBF reserve (MBFR). If fully exploited, this effect may also improve MBF to ischemic myocardium. Using insulin-dextrose infusions to induce HE, we conducted four experiments to determine (1) how insulin infusion duration, dose, and presence of insulin resistance affect MBFR response; and (2) the effect of an insulin-dextrose infusion given immediately following revascularization of STEMI on myocardial perfusion.

METHODS

The MBFR was determined using myocardial contrast echocardiography. Experiment 1 (insulin duration): 12 participants received an insulin-dextrose or saline infusion for 120 minutes. MBFR was measured at four time intervals during infusion. Experiment 2 (insulin dose): 22 participants received one of three insulin doses (0.5, 1.5, 3.0 mU/kg/minute) for 60 minutes. Baseline and 60-minute MBFRs were determined. Experiment 3 (insulin resistance): five metabolic syndrome and six type 2 diabetes (T2DM) participants received 1.5 mU/kg/minute of insulin-dextrose for 60 minutes. Baseline and 60-minute MBFRs were determined. Experiment 4 (STEMI): following revascularization for STEMI, 20 patients were randomized to receive either 1.5 mU/kg/minute insulin-dextrose infusion for 120 minutes or standard care. Myocardial contrast echocardiography was performed at four time intervals to quantify percentage contrast defect length.

RESULTS

Experiment 1: MBFR increased with time through to 120 minutes in the insulin-dextrose group and did not change in controls. Experiment 2: compared with baseline, MBFR increased in the 1.5 (2.42 ± 0.39 to 3.25 ± 0.77, P = .002), did not change in the 0.5, and decreased in the 3.0 (2.64 ± 0.25 to 2.16 ± 0.33, P = .02) mU/kg/minute groups. Experiment 3: compared with baseline, MBFR increase was only borderline significant in metabolic syndrome and T2DM participants (1.98 ± 0.33 to 2.59 ± 0.45, P = .04, and 1.67 ± 0.35 to 2.14 ± 0.21, P = .05). Experiment 4: baseline percentage contrast defect length was similar in both groups but with insulin decreased with time and was significantly lower than in controls at 60 minutes (2.8 ± 5.7 vs 13.7 ± 10.6, P = .02).

CONCLUSIONS

Presence of T2DM, insulin infusion duration, and dose are important determinants of the MBFR response to HE. When given immediately following revascularization for STEMI, insulin-dextrose reduces perfusion defect size at one hour. Hyperinsulinemic euglycemia may improve MBF following ischemia, but further studies are needed to clarify this.

Baseline Characteristics and Risk Profiles of Participants in the ISCHEMIA Randomized Clinical Trial

Importance

It is unknown whether coronary revascularization, when added to optimal medical therapy, improves prognosis in patients with stable ischemic heart disease (SIHD) at increased risk of cardiovascular events owing to moderate or severe ischemia.

Objective

To describe baseline characteristics of participants enrolled and randomized in the International Study of Comparative Health Effectiveness With Medical and Invasive Approaches (ISCHEMIA) trial and to evaluate whether qualification by stress imaging or nonimaging exercise tolerance test (ETT) influenced risk profiles.

Design, Setting, and Participants

The ISCHEMIA trial recruited patients with SIHD with moderate or severe ischemia on stress testing. Blinded coronary computed tomography angiography was performed in most participants and reviewed by a core laboratory to exclude left main stenosis of at least 50% or no obstructive coronary artery disease (CAD) (<50% for imaging stress test and <70% for ETT). The study included 341 enrolling sites (320 randomizing) in 38 countries and patients with SIHD and moderate or severe ischemia on stress testing. Data presented were extracted on December 17, 2018.

Main Outcomes and Measures

Enrolled, excluded, and randomized participants' baseline characteristics. No clinical outcomes are reported.

Results

A total of 8518 patients were enrolled, and 5179 were randomized. Common reasons for exclusion were core laboratory determination of insufficient ischemia, unprotected left main stenosis of at least 50%, or no stenosis that met study obstructive CAD criteria on study coronary computed tomography angiography. Randomized participants had a median age of 64 years, with 1168 women (22.6%), 1726 nonwhite participants (33.7%), 748 Hispanic participants (15.5%), 2122 with diabetes (41.0%), and 4643 with a history of angina (89.7%). Among the 3909 participants randomized after stress imaging, core laboratory assessment of ischemia severity (in 3901 participants) was severe in 1748 (44.8%), moderate in 1600 (41.0%), mild in 317 (8.1%) and none or uninterpretable in 236 (6.0%), Among the 1270 participants who were randomized after nonimaging ETT, core laboratory determination of ischemia severity (in 1266 participants) was severe (an eligibility criterion) in 1051 (83.0%), moderate in 101 (8.0%), mild in 34 (2.7%) and none or uninterpretable in 80 (6.3%). Among the 3912 of 5179 randomized participants who underwent coronary computed tomography angiography, 79.0% had multivessel CAD (n = 2679 of 3390) and 86.8% had left anterior descending (LAD) stenosis (n = 3190 of 3677) (proximal in 46.8% [n = 1749 of 3739]). Participants undergoing ETT had greater frequency of 3-vessel CAD, LAD, and proximal LAD stenosis than participants undergoing stress imaging.

Conclusions and Relevance

The ISCHEMIA trial randomized an SIHD population with moderate or severe ischemia on stress testing, of whom most had multivessel CAD.

Trial Registration

ClinicalTrials.gov Identifier: NCT01471522.

Influence of Population Selection on the 99th Percentile Reference Value for Cardiac Troponin Assays

OBJECTIVE

We sought to determine the effect of patient selection on the 99th reference percentile of 2 sensitive and 1 high-sensitivity (hs) cardiac troponin assays in a well-defined reference population.

METHODS

Individuals &gt;45 years old were randomly selected from 7 representative local community practices. Detailed information regarding the participants was collected via questionnaires. The healthy reference population was defined as individuals who had no history of vascular disease, hypertension, or heavy alcohol intake; were not receiving cardiac medication; and had blood pressure &lt;140/90 mmHg, fasting blood glucose &lt;110 mg/dL (approximately 6 mmol/L), estimated creatinine clearance &gt;60 mL · min−1 · (1.73 m2)−1, and normal cardiac function according to results of echocardiography. Samples were stored at −70 °C until analysis for cardiac troponin I (cTnI) and cardiac troponin T (cTnT) and N-terminal pro-B–type natriuretic peptide.

RESULTS

Application of progressively more stringent population selection strategies to the initial baseline population of 545 participants until the only individuals who remained were completely healthy according to the study criteria reduced the number of outliers seen and led to a progressive decrease in the 99th-percentile value obtained for the Roche hs-cTnT assay and the sensitive Beckman cTnI assay but not for the sensitive Siemens Ultra cTnI assay. Furthermore, a sex difference found in the baseline population for the hs-cTnT (P = 0.0018) and Beckman cTnI assays (P &lt; 0.0001) progressively decreased with more stringent population selection criteria.

CONCLUSIONS

The reference population selection strategy significantly influenced the 99th percentile reference values determined for troponin assays and the observed sex differences in troponin concentrations.

P1292 Prevalence and mechanisms of mitral regurgitation and its association with advanced heart failure in patients with a systemic right ventricle

Background

Although tricuspid regurgitation in patients with cardiac diseases is an established predictor of adverse outcomes, prevalence, mechanisms and clinical/prognostic value of non-systemic mitral regurgitation (MR) in patients with congenitally corrected transposition of great arteries (ccTGA) or simple transposition after Mustard or Senning procedures (TGA) are still poorly understood.

Purpose

To assess prevalence, mechanisms of MR and its association with severity of heart failure in patients with a systemic right ventricle (SRV).

Methods

From our digital echocardiographic database, we have identified all patients with a SRV who underwent echocardiography between 2014 and 2018. Severity of MR, size and function of SRV and subpulmonary LV were assessed from the latest echocardiographic studies.

Results

157 patients fulfilled inclusion criteria (89 post-Mustard/Senning, 68 ccTGA), median age 40.6 (33.1; 46.8) years, 57% male, median BNP 79.5 [38.3; 173.3] ng/l.

More than trivial MR was present in 44 (28.0%), further classified as mild, moderate and severe in 26 (16.6%), 15 (9.6%) and 3 (1.9%), respectively.

Principal mechanisms of MR included (i) device lead interference with the leaflet(s) in 26, (ii) organic pathology of mitral valve in 5 (2 prolapse, 2 cleft and 1 parachute mitral valve) and (iii) systolic leaflet(s) tethering ± annular dilatation in 4; no obvious cause of MR was identified in 10 patients.

Presence of more than trivial MR was significantly associated with NYHA class 3-4 (Chi-square 25.74, p &lt; 0.0001). Patients with MR also had higher BNP levels, larger LV with poorer systolic function and were more likely to have pulmonary stenosis (Table).

MR was less common in patients post-Mustard/Senning procedures compared to ccTGA (p &lt; 0.0001, Table); however, patients from the former group were more likely to have severe heart failure (Figure).

Conclusions

Non-systemic MR in patients with a SRV is relatively uncommon, but when present is associated with LV dilatation and systolic dysfunction, raised BNP levels, and heart failure symptoms. Predominant underlying mechanisms were device leads, organic pathology, and valve tethering. MR should be routinely assessed in SRV patients, particularly those with previous Mustard/Senning procedures, and be taken into account in decision making and timing interventions.

Characteristics of 157 patients with SRV Parameter No/trivial MR (N = 113) Mild-severe MR (N = 44) P value Age, years Mustard/Senning ccTGA Pulmonary stenosis NYHA class 3-4 ICD/Pacemaker lead 39.5 (33.1; 45.7) 75 (66%) 38 (34%) 13 (12%) 7 (6%) 31 (27%) 44.4 (32.7; 52) 14 (32%) 30 (68%) 12 (27%) 17 (39%) 32 (73%) 0.105 &lt;0.0001 &lt;0.0001 0.022 &lt;0.0001 &lt;0.0001 LV EDDi, cm/m2 LV FAC, % MAPSE, mm SRV EDAi, cm2/m&sup2; TAPSE, mm 2.11 (1.9; 2.45) 48 (42; 52.5) 18 (14; 22) 17.6 (15.0; 20.2) 12 (9; 15) 2.5 (2.0; 2.9) 40 (34; 48.8) 14.6 (11.5; 16.5) 17.5 (14.4; 22.2) 10.5 (9; 13) 0.0007 0.0011 0.0005 0.754 0.435 BNP 68 (35.3; 104.3) 177 (62.5; 345.3) &lt;0.0001 Values are reported as median (25th; 75th percentile) or n(%)

Abstract P1292 Figure. SRV patients with more than trivial MR

P679 Subpulmonary left ventricular dysfunction is associated with severity of heart failure in patients with systemic right ventricle

Background

Dysfunction of systemic right ventricle (SRV) in patients with congenitally corrected transposition of great arteries (ccTGA) or simple transposition (TGA) is commonly associated with exercise intolerance, heart failure and death. However, the relevance of subpulmonary left ventricular (LV) function in these settings is unknown.

Purpose

To examine the relation between severity of heart failure and echocardiographic parameters of subpulmonary LV size and function in patients with SRV.

Methods

We identified all patients with SRV from our digital echocardiographic database between 2014 and 2018. The size and function of SRV and subpulmonary LV were assessed in the most recent examination. Clinical data were collected from electronic patient records.

Results

We included 157 patients with SRV, median age 40.6 [33.1; 46.8] years, 57% male. 133 (85%) patients had NYHA functional class 1-2 and 24 (15%) NYHA class 3-4.

Patients with NYHA class 3-4 were older, had larger SRV and subpulmonary LV with poorer function and higher BNP level (Table, Figure A).

LV fractional area change (FAC) had higher sensitivity and specificity in differentiation of patients with severe heart failure than SRV FAC (Figurel B) with LV FAC cut-off value &lt;39.2% showing the highest accuracy in prediction of NYHA class 3-4 (Se 83% and Sp 88%) and 86% Sp in predicting BNP &gt; 100 ng/l.

LV end-diastolic diameter and area, MAPSE and FAC significantly correlated with BNP level (p &lt; 0.0001; p = 0.001; p = 0.007; and p = 0.0002, respectively).

In Multivariate Cox regression analysis LV FAC and RV FAC were the only independent associates of NYHA class 3-4 (HR 0.69 [95%CI 0.55-0.86], p = 0.001 and HR 0.71 [95%CI 0.55-0.93], p = 0.012, respectively), while age, degree of tricuspid regurgitation and BNP were not.

Conclusions

Subpulmonary LV dysfunction is strongly associated with NYHA class 3-4 heart failure in patients with SRV. LV FAC is more accurate than SRV FAC in predicting heart failure symptoms. Subpulmonary LV should be accurately assessed in all SRV patients and be taken into account in clinical decision making and timing for interventions.

Characteristics of 157 patients with SRV Parameter NYHA Class 1-2 (N = 133) NYHA Class 3-4 (N = 24) P value Age, years 39.1 (31.9; 45.7) 46.5 (43.9; 58.1) &lt;0.0001 RV EDAi, cm2/m2 17.4 (15.2; 20.1) 21.8 (17.5; 25.6) 0.0002 RV FAC, % 29.5 (23; 35) 22 (20; 27) &lt;0.0001 LV EDAi, cm2/m2 12.0 (10.1; 14.1) 16.4 (11.6; 19.1) 0.0008 Reduced LV function by eyeballing 3 (2%) 18 (75%) &lt;0.0001 BNP, ng/l 66 (35; 109) 356 (196; 512) &lt;0.0001 Data presented as median (25th; 75th percentiles)

Abstract P679 Figure.