Comparative effectiveness of exercise electrocardiography versus exercise echocardiography in women presenting with suspected coronary artery disease: a randomized study.

Aims: There is a paucity of randomized diagnostic studies in women with suspected coronary artery disease (CAD). This study sought to assess the relative value of exercise stress echocardiography (ESE) compared with exercise electrocardiography (Ex-ECG) in women with CAD. Methods and results: Accordingly, 416 women with no prior CAD and intermediate probability of CAD (mean pre-test probability 41%), were randomized to undergo either Ex-ECG or ESE. The primary endpoints were the positive predictive value (PPV) for the detection of significant CAD and downstream resource utilization. The PPV of ESE and Ex-ECG were 33% and 30% (P = 0.87), respectively for the detection of CAD. There were similar clinic visits (36 vs. 29, P = 0.44) and emergency visits with chest pain (28 vs. 25, P = 0.55) in the Ex-ECG and ESE arms, respectively. At 2.9 years, cardiac events were 6 Ex-ECG vs. 3 ESE, P = 0.31. Although initial diagnosis costs were higher for ESE, more women underwent further CAD testing in the Ex-ECG arm compared to the ESE arm (37 vs. 17, P = 0.003). Overall, there was higher downstream resource utilization (hospital attendances and investigations) in the Ex-ECG arm (P = 0.002). Using National Health Service tariffs 2020/21 (British pounds) the cumulative diagnostic costs were 7.4% lower for Ex-ECG compared with ESE, but this finding is sensitive to the cost differential between ESE and Ex-ECG. Conclusion: In intermediate-risk women who are able to exercise, Ex-ECG had similar efficacy to an ESE strategy, with higher resource utilization whilst providing cost savings.

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.

Catastrophic stroke in a patient with left ventricular non-compaction.

SummaryWe present the case of a 32-year-old man who presented with a remote history of chest pain and was diagnosed with non-compaction cardiomyopathy on echocardiography. On presentation, he was relatively asymptomatic with normal cardiac function. Unfortunately, he presented 1 year later with a catastrophic embolic stroke. LEARNING POINTS: Left ventricular non-compaction (LVNC) is a myocardial disorder characterised by prominent left ventricular (LV) trabeculae, a thin compacted layer and deep intertrabecular recesses.Two-dimensional echocardiography with colour Doppler is the study of choice for diagnosis and follow-up of LVNC. CMR serves an important role where adequate echocardiographic imaging cannot be obtained.LVNC is associated with high rates of mortality and morbidity in adults, including heart failure, thromboembolic events and tachyarrhythmias.

Long-Term Association of Dipyridamole Stress Myocardial Contrast Echocardiography versus Single-Photon Emission Computed Tomography with Clinical Outcomes in Patients with Known or Suspected Coronary Artery Disease.

BACKGROUND: Single-photon emission computed tomography (SPECT) is a well-established method to evaluate patients with coronary artery disease. Myocardial contrast echocardiography (MCE) is an imaging technique that allows the assessment of myocardial perfusion in real time. Previous research has shown that vasodilator MCE is superior to SPECT for the prediction of hard events. The aim of this study was to investigate the long-term association of SPECT and MCE with clinical outcomes in patients with known or suspected coronary artery disease. METHODS: Accordingly, 258 patients who underwent MCE and SPECT as part of multicenter studies performed prospectively were followed up for hard events (all-cause mortality and nonfatal myocardial infarction). The mean age was 63.4 ± 5.5 years, 186 (72.1%) were men, and 32 (12.4%) had left ventricular systolic dysfunction. We calculated the ratio of the number of abnormal segments (at rest and/or stress) to the total number of segments expressed as MCE and SPECT indices. RESULTS: Over a mean follow-up period of 80.4 ± 6.1 months, 46 patients had hard events. MCE and SPECT indices were associated with all-cause mortality on univariate analysis (P = .008 and P = .035, respectively) but only MCE index was independently associated with hard events (hazard ratio, 4.24; 95% CI, 1.27-14.15; P = .019), beyond clinical data and left ventricular function, and independently associated with hard cardiac events (hazard ratio, 4.78; 95% CI, 1.06-21.59; P = .042). CONCLUSIONS: MCE but not SPECT showed a long-term association with outcome. These results thus favor the routine use of MCE in the long-term assessment of patients with known or suspected coronary artery disease.

Cost-effectiveness of a management strategy based on exercise echocardiography versus exercise electrocardiography in patients presenting with suspected angina during long term follow up: A randomized study.

INTRODUCTION: Exercise ECG (Ex-ECG) is advocated by guidelines for patients with low - intermediate probability of coronary artery disease (CAD). However, there are no randomized studies comparing Ex-ECG with exercise stress echocardiography (ESE) evaluating long term cost-effectiveness of each management strategy. METHODS: Accordingly, 385 patients with no prior CAD and low-intermediate probability of CAD (mean pre-test probability 34%), were randomized to undergo either Ex-ECG (194 patients) or ESE (191 patients). The primary endpoint was clinical effectiveness defined as the positive predictive value (PPV) for the detection of CAD of each test. Cost-effectiveness was derived using the cumulative costs incurred by each diagnostic strategy during a mean of follow up of 3.0 years. RESULTS: The PPV of ESE and Ex-ECG were 100% and 64% (p = 0.04) respectively for the detection of CAD. There were fewer clinic (31 vs 59, p < 0.01) and emergency visits (14 vs 30, p = 0.01) and lower number of hospital bed days (8 vs 29, p < 0.01) in the ESE arm, with fewer patients undergoing coronary angiography (13.4% vs 6.3%, p = 0.02). The overall cumulative mean costs per patient were £796 for Ex-ECG and £631 for ESE respectively (p = 0.04) equating to a >20% reduction in cost with an ESE strategy with no difference in the combined end-point of death, myocardial infarction, unplanned revascularization and hospitalization for chest pain between ESE and Ex-ECG (3.2% vs 3.7%, p = 0.38). CONCLUSION: In patients with low to intermediate pretest probability of CAD and suspected angina, an ESE management strategy is cost-effective when compared with Ex-ECG during long term follow up.

Diagnostic Concordance and Clinical Outcomes in Patients Undergoing Fractional Flow Reserve and Stress Echocardiography for the Assessment of Coronary Stenosis of Intermediate Severity.

BACKGROUND: The ischemic consequences of coronary artery stenosis can be assessed by invasive fractional flow reserve (FFR) or by noninvasive imaging. We sought to determine (1) the concordance between wall thickening assessment during clinically indicated stress echocardiography (SE) and FFR measurements and (2) the factors associated with hard events in these patients. METHODS: Two hundred twenty-three consecutive patients who underwent SE and invasive FFR measurements in close succession were analyzed retrospectively for diagnostic concordance and clinical outcomes. RESULTS: At the vessel level, the sensitivity, specificity, positive predictive value, and negative predictive value of SE for identifying significant disease as assessed by FFR was 68%, 75%, 43%, and 89%, respectively. The greatest discordance was seen in patients with wall thickening abnormalities (WTAs) and negative FFR. During a follow-up of 3.6 ± 2.2 years, there were 23 cardiovascular (CV) events (death and nonfatal myocardial infarction). The number of wall segments with inducible WTAs emerged as the strongest factor associated with CV events (hazard ratio, 1.18 [1.05-1.34]; P = .008). FFR was not associated with outcome. There was a significant increase in event rate in patients with WTA/negative FFR versus no WTA/negative FFR (P = .01), but no significant difference versus WTA/positive FFR (P = .85). CONCLUSIONS: In a patient population with significant CV risk factors, a normal SE had a high negative predictive value for excluding abnormal FFR. WTAs were associated with outcomes regardless of FFR value, suggesting that this is a superior marker of ischemia to FFR.

Stress Echocardiography in Stable Coronary Artery Disease.

PURPOSE OF REVIEW: Stress echocardiography (SE) is a well-established technique for the diagnosis and risk stratification of patients with known or suspected coronary artery disease (CAD). This review article summarizes the status of SE in CAD, including testing protocols, clinical efficacy and current use of newer technologies: myocardial perfusion, strain imaging, three-dimensional echocardiography and adjunctive carotid ultrasonography. RECENT FINDINGS: Recent major findings in SE include the clinical value of myocardial perfusion imaging in multicentre studies, as well as when added to left ventricular (LV) wall motion assessment in clinical service. Additionally, SE has been shown to be more cost-effective than exercise ECG in patients with low-intermediate pre-test probability of CAD. Adjunctive atherosclerosis imaging by carotid ultrasonography (CU) to ischaemia testing by SE provides synergistic prognostic value, equivalent to hybrid imaging by PET-CT. Despite the development of newer and more expensive imaging modalities, SE remains the cornerstone for the assessment of CAD and has excellent clinical efficacy, is safe and is cost-effective.

Relative clinical and economic impact of exercise echocardiography vs. exercise electrocardiography, as first line investigation in patients without known coronary artery disease and new stable angina: a randomized prospective study.

AIMS: Exercise electrocardiography (ExECG) is widely used in suspected stable angina (SA) as the initial test for the evaluation of coronary artery disease (CAD). We hypothesized that exercise stress echo (ESE) would be efficacious with cost advantage over ExECG when utilized as the initial test. METHODS AND RESULTS: Consecutive patients with suspected SA, without known CAD were randomized into ExECG or ESE. Patients with positive tests were offered coronary angiography (CA) and with inconclusive tests were referred for further investigations. All patients were followed-up for cardiac events (death, myocardial infarction, and unplanned revascularization). Cost to diagnosis of CAD was calculated by adding the cost of all investigations, up to and including CA. In the 194 and 191 patients in the ExECG vs. ESE groups, respectively, pre-test probability of CAD was similar (34 ± 23 vs. 35 ± 25%, P = 0.6). Results of ExECG were: 108 (55.7%) negative, 14 (7.2%) positive, 72 (37.1%) inconclusive and of ESE were 181 (94.8%) negative, 9 (4.7%) positive, 1 (0.5%) inconclusive, respectively. Patients with obstructive CAD following positive ESE vs. Ex ECG were 9/9 vs. 9/14, respectively (P = 0.04). Cost to diagnosis of CAD was £266 for ESE vs. £327 for ExECG (P = 0.005). Over a mean follow-up period of 21 ± 5 months, event rates were similar between the two groups. CONCLUSION: In this first randomized study, ESE was more efficacious and demonstrated superior cost-saving, compared with ExECG when used as the initial investigation for the evaluation of CAD in patients with new-onset suspected SA without known CAD.

The clinical efficacy and long-term prognostic value of stress echocardiography in octogenarians.

INTRODUCTION: Although stress echocardiography (SE) is invaluable in younger populations, its prognostic value may be attenuated in the elderly due to shorter life expectancy and the frequent presence of severe comorbidities. This study sought to evaluate the clinical effectiveness of SE in octogenarians, particularly its prognostic value over clinical variables, in predicting hard events. METHODS: A total of 374 consecutive octogenarians who underwent SE for evaluation of coronary artery disease (CAD) were assessed for feasibility, diagnostic accuracy and safety of the test, and followed up for hard outcomes (all-cause mortality, cardiovascular (CV) deaths and non-fatal myocardial infarction (NFMI)). Cox regression analysis was performed to identify predictors of outcome. RESULTS: Of the 374 tests, 360 (96.3%) were diagnostic. Of the 50 patients with inducible ischaemia, 33 patients (66%) proceeded to angiography of which 27 (82%) patients had significant CAD. During long-term follow-up of 4.0±2.0 years, there were 127 deaths and 36 NFMIs. The annualised mortality, NFMI and combined mortality /NFMI rates were 8.1%, 1.8% and 9.4% for patients with a normal SE and 12.1%, 5.5% and 14.1% for those with an abnormal SE, respectively. Predictors of NFMI on multivariate analysis were prior CAD (HR 2.89, CI 1.03 to 8.15, p=0.045), peripheral vascular disease (HR 3.33, CI 1.18 to 9.45, p=0.02), and inducible ischaemia (HR 3.97, CI 1.49 to 10.55, p=0.006). In patients without prior history of CAD, inducible ischaemia was the only independent predictor of NFMI (HR 8.72, CI 1.46 to 52.2, p=0.018). The larger the extent of ischaemia, the greater the incidence of NFMI. The independent predictors of CV events (NFMI or CV mortality) were PAD (HR 2.81, CI 1.21 to 6.52, p=0.016) and peak wall motion score index (HR 5.71, CI 1.67 to 19.6, p=0.006). Although inducible ischaemia predicted all-cause mortality on unadjusted analysis, it did not on multivariate analysis. CONCLUSIONS: In octogenarians, SE demonstrated excellent feasibility, safety and diagnostic accuracy. SE parameters were independent predictors of NFMI and CV events, and the presence of inducible ischaemia was associated with a 50% increase in all-cause mortality.

Prognostic usefulness of contemporary stress echocardiography in patients with left bundle branch block and impact of contrast use in improving prediction of outcome.

AIMS: Patients with symptomatic left bundle branch block (LBBB) may have myocardial ischaemia due to both coronary artery disease and/or cardiomyopathy (microcirculatory abnormalities) and may have concomitant left ventricular (LV) dysfunction. We aimed to assess the feasibility and prognostic value of contemporary stress echocardiography (SE), which can uncover both pathophysiologies in LBBB patients in routine clinical practice, and also aimed to assess the additive value of contrast SE. METHODS AND RESULTS: Accordingly, 190 consecutive patients (age 70.5 ± 11.3 years, LV ejection fraction = 50.1 ± 10%) with symptomatic LBBB who underwent SE over 6 years were assessed, of which 142 (75%) underwent contrast SE and 176 (92.6%) had diagnostic SE. Inducible ischaemia was present in 25 (14.2%) patients. During follow-up (35.4 ± 20.2 months) there were 32 deaths (18%) and 18 (10.2%) first cardiovascular (CV) events (acute myocardial infarction/mortality) in the 176 patients with diagnostic studies. Wall thickening score index at peak stress (WTSIpeak), which measures combined LV function and inducible ischaemia, was an independent predictor of mortality (HR = 3.78, 95% CI = 1.39-10.31, P = 0.01) and CV events (HR = 3.96, 95% CI = 1.1-14.3, P = 0.036). An abnormal SE (myocardial ischaemia and/or abnormal LV function) predicted an almost three-fold increase in all-cause mortality and CV events compared with normal SE. Amongst the confounders affecting assessment of wall thickening in LBBB and conventional prognostic variables, use of contrast was an independent predictor (P = 0.034) of WTSI1.16 (optimal predictor of mortality/CV outcome). CONCLUSION: SE in patients with LBBB demonstrated high feasibility and the combination of LV systolic function and myocardial ischaemia provided important prognostic information. Contrast-enhanced SE improved the prediction of outcome.

Imaging the heart failure patient-need for accurate measurements of left ventricular volumes and ejection fraction: the role of three-dimensional and contrast echocardiography.

PURPOSE OF REVIEW: Left ventricular ejection fraction (LVEF) is a powerful prognostic marker in heart failure and plays a pivotal role in the allocation of many treatments that reduce morbidity and mortality. Although unenhanced two-dimensional echocardiography (2DE) is the most ubiquitous tool for the assessment of left ventricular (LV) size and systolic function, it does not provide reliable, reproducible and accurate measures. The purpose of this review is to critically appraise contrast echocardiography and three-dimensional echocardiography (3DE) for the assessment of LVEF and LV volumes. RECENT FINDINGS: Contrast echocardiography results in more accurate assessment of LVEF and LV volumes than unenhanced 2DE, significantly improving correlation with cardiac magnetic resonance, with comparable reproducibility. Contrast echocardiography reduces downstream testing, frequently alters patient management, and results in substantial cost savings. 3DE shows higher levels of agreement with cardiac magnetic resonance over unenhanced 2DE for LVEF and LV volumes, but requires adequate image quality, and consistently underestimates LV volumes due to limited spatial resolution. SUMMARY: The advent of contrast 2DE and 3DE has marked the dawn of significant improvements in the precision and reproducibility of echocardiography. Contrast 3DE improves LV assessment in patients with suboptimal images, but further work is needed to demonstrate incremental benefit over contrast echocardiography.

The clinical impact of contemporary stress echocardiography in morbid obesity for the assessment of coronary artery disease.

OBJECTIVE: Non-invasive cardiac imaging may suffer from poor image quality in morbidly obese individuals. This study aimed to determine the clinical value of contemporary stress echocardiography (SE) in morbidly obese patients referred for assessment of suspected coronary artery disease (CAD). METHODS: This prospective, multicentre observational study was conducted in two district hospitals and one tertiary centre in London, UK. Individuals with body mass index ≥35 kg/m(2) referred for SE were evaluated. The percentage of patients with obstructive CAD on coronary angiography, following abnormal SE, was assessed. Patient outcomes were determined with follow-up for the composite end-point of all-cause mortality, myocardial infarction and late revascularisation. RESULTS: Over a 13-month period, 209 morbidly obese patients underwent SE, and contrast agent was used in 96% of patients. A diagnostic result was obtained in 200/209 (96%) patients. Of 32 (15%) patients with inducible ischaemia, 25 underwent angiography, 22 (88%) had corresponding significant CAD and, of these, 16 (77%) underwent revascularisation. Conversely, only 2/157 patients (1.3%) with normal SE underwent angiography, and none underwent revascularisation. Over a mean follow-up period of 17.8±5.4 months, there were nine events. The annualised cardiac event rate after a normal SE was 0.95%. Events were more frequent in patients with inducible ischaemia versus those without ischaemia (5/32 (15.6%) vs 4/153 (2.6%); p=0.002). Ejection fraction <50% (HR 9.5; 95% CI 2.4 to 38.0; p=0.002) and inducible ischaemia (HR 9.4; 95% CI 2.5 to 35.8; p=0.001) were predictors of outcome on univariable Cox regression analysis. CONCLUSIONS: Contemporary SE has excellent feasibility and positive predictive value and resulted in appropriate risk stratification of symptomatic patients with significant obesity. A normal SE portends an excellent outcome over the short-intermediate term in this high-risk patient population.

Novel techniques in stress echocardiography: a focus on the advantages and disadvantages.

Stress echocardiography (SE) is an established tool not only for the assessment of coronary artery disease (CAD), but also for the evaluation of valvular disease and cardiomyopathy. New techniques, namely contrast echocardiography for function and perfusion including assessment of coronary flow reserve, strain imaging, 3-dimensional echocardiography, Doppler-derived coronary flow reserve and multimodality echocardiography, have been incorporated into stress protocols for improving assessment of cardiac disease. In this review, the advantages and disadvantages of these novel SE techniques are examined in terms of feasibility, accuracy, reproducibility and applications.

The benefits of revascularization in chronic heart failure.

Recent efforts have reduced the mortality from coronary artery disease (CAD), with the consequent increase in heart failure with reduced left ventricular function, referred to as ischaemic cardiomyopathy (ICM). As ischemic left ventricular (LV) dysfunction may be partially or completely reversible by revascularization in the presence of viable myocardium, the assessment of myocardial viability is central to the management of ICM. Decades of observational analyses have provided positive evidence for the role of revascularization in hibernating myocardium in improving survival. However, recently the Surgical Treatment for Ischaemic Heart Failure (STICH) trial has challenged this notion, highlighting the noninferiority of optimal medical therapy (OMT) over revascularization and OMT. In this review, we discuss noninvasive imaging modalities to assess myocardial viability and the impact of myocardial viability on revascularization. We critically appraise the STICH trial and suggest an algorithm for viability testing before revascularization in patients with ICM and significant LV dysfunction.