Energy wavelet signal processed ECG and standard 12 lead ECG: Diagnosis of early diastolic dysfunction.

BACKGROUND: Left ventricular (LV) diastolic dysfunction (LVDD) is the result of impaired LV relaxation and identifies those at risk of developing heart failure. Echocardiography has been used as the gold standard to identify early LVDD. The signal processed electrocardiogram (hsECG) has demonstrated effectiveness to detect early LVDD. Whether or not the standard 12­lead electrocardiogram (ECG) can accurately predict early LVDD is not known. METHODS: A standard 12­lead ECG including signal processing (hsECG) was performed in 569 patients. Patients with atrial fibrillation, bundle branch block, pre-excitation, left ventricular hypertrophy or known cardiovascular disease were excluded, leaving 464 examinations for analysis. Early LVDD was diagnosed by established methods using echocardiography. Repolarization abnormalities (T wave discordance) in V1, V6, I and aVL and the hsECG were compared to the echocardiographic findings to establish diagnostic accuracy. RESULTS: A total of 84 (18.1%) patients were diagnosed with early LVDD. A combination of a borderline or abnormal finding on the hsECG produced the best diagnostic model (sensitivity 84.5%, specificity 47.9%). The best performing ECG lead was V1 with a sensitivity of 38.1% and specificity of 92.1%. Regression analysis demonstrated increasing age and V1 to be predictive of LVDD. CONCLUSIONS: The hsECG displayed reasonable ability to detect early LVDD. Other than V1, repolarization abnormalities on the standard 12­lead ECG did not. While lead V1 showed promise in detecting LVDD, whether this or any other simple ECG variable can predict future LVDD would be of further interest.

Three-dimensional echocardiographic acquisition and validity of left ventricular volumes and ejection fraction.

Transthoracic (TTE) and transesophageal (TEE) three-dimensional echocardiography (3DE) is now used in daily clinical practice. Advancements in technology have improved image acquisition with higher frame rates and increased resolution. Different 3DE acquisition techniques can be used depending upon the structure of interest and if volumetric analysis is required. Measurements of left ventricular (LV) volumes are the most common use of 3DE clinically but are highly dependent upon image quality. Three-dimensional LV function analysis has been made easier with the development of automated software, which has been found to be highly reproducible. However, further research is needed to develop normal reference range values of LV function for both 3D TTE and TEE.

Treatment of acute otitis media in children under 2 years of age.

BACKGROUND: Recommendations vary regarding immediate antimicrobial treatment versus watchful waiting for children younger than 2 years of age with acute otitis media. METHODS: We randomly assigned 291 children 6 to 23 months of age, with acute otitis media diagnosed with the use of stringent criteria, to receive amoxicillin-clavulanate or placebo for 10 days. We measured symptomatic response and rates of clinical failure. RESULTS: Among the children who received amoxicillin-clavulanate, 35% had initial resolution of symptoms by day 2, 61% by day 4, and 80% by day 7; among children who received placebo, 28% had initial resolution of symptoms by day 2, 54% by day 4, and 74% by day 7 (P=0.14 for the overall comparison). For sustained resolution of symptoms, the corresponding values were 20%, 41%, and 67% with amoxicillin-clavulanate, as compared with 14%, 36%, and 53% with placebo (P=0.04 for the overall comparison). Mean symptom scores over the first 7 days were lower for the children treated with amoxicillin-clavulanate than for those who received placebo (P=0.02). The rate of clinical failure--defined as the persistence of signs of acute infection on otoscopic examination--was also lower among the children treated with amoxicillin-clavulanate than among those who received placebo: 4% versus 23% at or before the visit on day 4 or 5 (P<0.001) and 16% versus 51% at or before the visit on day 10 to 12 (P<0.001). Mastoiditis developed in one child who received placebo. Diarrhea and diaper-area dermatitis were more common among children who received amoxicillin-clavulanate. There were no significant changes in either group in the rates of nasopharyngeal colonization with nonsusceptible Streptococcus pneumoniae. CONCLUSIONS: Among children 6 to 23 months of age with acute otitis media, treatment with amoxicillin-clavulanate for 10 days tended to reduce the time to resolution of symptoms and reduced the overall symptom burden and the rate of persistent signs of acute infection on otoscopic examination. (Funded by the National Institute of Allergy and Infectious Diseases; ClinicalTrials.gov number, NCT00377260.).

Supporting Children and Families in Medical Settings: Insights from Child Life Specialists During the COVID-19 Pandemic.

Medical settings can be frightening and stressful places for pediatric patients and their families. During the COVID-19 pandemic fear and anxiety associated with receiving medical care increased as medical facilities dramatically altered the way they functioned in attempts to stop the spread of the virus. Certified Child Life Specialists (CCLSs) are medical professionals who provide psychosocial support for pediatric patients and their families by helping them understand and cope with medical procedures and the medical environment. In this role, CCLSs are likely to have important insights into the experiences and needs of pediatric patients and their families during COVID-19. Using a mixed-methods design, 101 CCLSs completed an online survey and 15 participated in follow-up interviews examining their experiences with and observations of children and families in medical environments during the pandemic. Participants emphasized a need to maintain a focus on child- and family-centered care for the well-being of patients and their families. While recognizing the need to socially distance to limit the spread of COVID, participants expressed concern about restrictive policies that did not balance the physical and mental health needs of patients and families. Participants also discussed the important role of child life services during the pandemic and the unique and multifaceted contributions CCLSs made to support patients, families, other medical professionals, and communities. Recommendations for supporting children and families in medical environments moving forward are discussed in light of lessons learned during the pandemic.

Rate pressure product, age predicted maximum heart rate or heart rate reserve. Which one better predicts cardiovascular events following exercise stress echocardiography?

BACKGROUND: Age-predicted maximum heart rate (APMHR) has been demonstrated to be a poor predictor of future cardiovascular (CV) events and is yet to be validated as a termination point during exercise testing. In contrast, maximum rate pressure product (MRPP) is recognized as a strong predictor of CV outcome with superior CV event prediction over APMHR. Heart rate reserve (HRR) has been shown to be a powerful predictor of CV mortality during exercise testing, however thus far, this is not confirmed for non-fatal CV events. The aim of this study was to compare APMHR, MRPP and HRR as predictors of CV events following otherwise negative exercise treadmill testing. METHODS: After exclusions, 1080 patients being investigated for coronary artery disease performed an exercise stress echocardiogram (ESE) to volitional fatigue on a motorised treadmill. Blood pressure was measured manually, and ultrasound images performed as per current American Society of Echocardiography guidelines. Rate pressure product and HRR were calculated throughout the test and maximum values were identified. Patients were followed for 5.3±2.6 mean years. RESULTS: From receiver operating characteristic analysis, cut points were established for APMHR (94.6%) (AUC 0.687), MRPP (25085) (AUC 0.729) and HRR% (95.9) (AUC 0.688). MRPP outperformed both APMHR and HRR% for the prediction of future CV events. Furthermore, on Cox proportional hazard analysis MRPP was the strongest uni- and multivariate predictor (p<0.0001) with APMHR and HRR% failing to reach any statistical significance. CONCLUSIONS: The current study demonstrates the substantial prognostic power of MRPP over both APMHR and HRR% to predict CV events following an otherwise negative ESE for myocardial ischemia.

Safety and Efficacy of Scientist Led Exercise Stress Testing for Arrhythmia Provocation and Chronotropic Competence.

For many years, non physician led exercise stress testing performed for the investigation of coronary artery disease has been endorsed by many cardiovascular (CV) societies and associations around the world. The safety guidelines don't currently include the performing of these tests for arrhythmia provocation or chronotropic assessment. Therefore, the aim of this study was to assess the safety and efficacy of non physician led EST performed for suspected arrhythmias, chronotropic competence, long QT, and accessory pathway conduction (APC) assessment. A total of 486 patients performed an exercise stress test for either of the above suspected conditions and were followed for 1.8 years ± 1.5 years. Tests were performed by a trained cardiac scientist with all reports over-read by a consultant Cardiologist. There were no significant adverse events (myocardial infarction, arrhythmia causing hemodynamic compromise or syncope) at time of testing. A total of 12.1% of patients required further follow up consisting of either a cardiac pacemaker, an implantable cardioverter defibrillator, radiofrequency ablation, Direct-Current cardioversion or a change in medications. Interobserver agreement between the Cardiologist and cardiac scientist was 98.4% indicating excellent agreement. In conclusion, the present study demonstrates that cardiac scientists can safely perform non physician led EST for the investigation of suspected arrhythmias, chronotropic competence, long QT, and APC assessment with a diagnostic interpretation equivalent to that of a consultant Cardiologist.

Prediction of hospital outcome in septic shock: a prospective comparison of tissue Doppler and cardiac biomarkers.

INTRODUCTION: Diastolic dysfunction as demonstrated by tissue Doppler imaging (TDI), particularly E/e' (peak early diastolic transmitral/peak early diastolic mitral annular velocity) is common in critical illness. In septic shock, the prognostic value of TDI is undefined. This study sought to evaluate and compare the prognostic significance of TDI and cardiac biomarkers (B-type natriuretic peptide (BNP); N-terminal proBNP (NTproBNP); troponin T (TnT)) in septic shock. The contribution of fluid management and diastolic dysfunction to elevation of BNP was also evaluated. METHODS: Twenty-one consecutive adult patients from a multidisciplinary intensive care unit underwent transthoracic echocardiography and blood collection within 72 hours of developing septic shock. RESULTS: Mean +/- SD APACHE III score was 80.1 +/- 23.8. Hospital mortality was 29%. E/e' was significantly higher in hospital non-survivors (15.32 +/- 2.74, survivors 9.05 +/- 2.75; P = 0.0002). Area under ROC curves were E/e' 0.94, TnT 0.86, BNP 0.78 and NTproBNP 0.67. An E/e' threshold of 14.5 offered 100% sensitivity and 83% specificity. Adjustment for APACHE III, cardiac disease, fluid balance and grade of diastolic function, demonstrated E/e' as an independent predictor of hospital mortality (P = 0.019). Multiple linear regression incorporating APACHE III, gender, cardiac disease, fluid balance, noradrenaline dose, C reactive protein, ejection fraction and diastolic dysfunction yielded APACHE III (P = 0.033), fluid balance (P = 0.001) and diastolic dysfunction (P = 0.009) as independent predictors of BNP concentration. CONCLUSIONS: E/e' is an independent predictor of hospital survival in septic shock. It offers better discrimination between survivors and non-survivors than cardiac biomarkers. Fluid balance and diastolic dysfunction were independent predictors of BNP concentration in septic shock.

Left ventricular volume measurement with echocardiography: a comparison of left ventricular opacification, three-dimensional echocardiography, or both with magnetic resonance imaging.

AIMS: Both contrast enhanced (CE) two-dimensional echocardiography (2DE) and three-dimensional echocardiography (3DE) have been proposed as techniques to improve the accuracy of left ventricular (LV) volume measurements. We sought to examine the accuracy of non-contrast (NC) and CE-2DE and 3DE for calculation of LV volumes and ejection fraction (EF), relative to cardiac magnetic resonance imaging (MRI). METHODS AND RESULTS: We studied 50 patients (46 men, age 63 +/- 10 year) with past myocardial infarction who underwent echocardiographic assessment of LV volume and function. All patients sequentially underwent NC-2DE followed by NC-3DE. CE-2DE and CE-3DE were acquired during contrast infusion. Resting echocardiographic image quality was evaluated on the basis of NC-2DE. The mean LV end-diastolic volume (LVEDV) of the group by MRI was 207 +/- 79 mL and was underestimated by 2DE (125 +/- 54 mL, P = 0.005), and less by CE-2DE (172 +/- 58 mL, P = 0.02) or 3DE (177 +/- 64 mL, P = 0.08), but EDV was comparable by CE-3DE (196 +/- 69 mL, P = 0.16). Limits of agreement with MRI were similar for NC-3DE and CE-2DE, with the best results for CE-3D. Results were similar for calculation of LVESV. Patients were categorized into groups of EF (< or =35, 35-50, >50%) by MRI. NC-2DE demonstrated a 68% agreement (kappa 0.45, P = 0.001), CE-2DE a 62% agreement (kappa 0.20, P = 136), NC-3DE a 74% agreement (kappa 0.39, P = 0.005) and CE-3DE an 80% agreement (kappa 0.56, P < 0.001). CONCLUSION: CE-2DE is analogous to NC-3DE in accurate categorization of LV function. However, CE-3DE is feasible and superior to other NC- and CE-techniques in patients with previous infarction.

Comparison of heart rate reserve, age predicted maximum heart rate and rate pressure product as predictors of future cardiovascular events following a negative dobutamine stress echocardiogram.

Background: Dobutamine stress echocardiography (DSE) is a commonly used diagnostic stress test for the assessment of various cardiac pathologies on patients unable to perform exercise. Unlike exercise, there is no reliable subjective termination end-point such as fatigue to rely on. Consequently, DSE's are often concluded at a predetermined age predicted maximal heart rate (APMHR) such as 85%. The aim of this study was to assess if APMHR, heart rate reserve (HRR) and the maximum rate pressure product (MRPP) are valid measures of future cardiovascular (CV) events in otherwise negative DSEs.Methods: Following exclusions, receiver operating curve (ROC) analyses were performed on 652 patients using CV events during the follow-up period (4.2 ± 1.8 years) as the outcome variable.Results: ROC analyses failed to produce a statistically valid model for MRPP (p = .227, area under curve (AUC)=0.55) with a sensitivity and specificity of 21.1% and 91.9%, respectively at the optimal cut point (14948 MRPP). To the contrary, APMHR produced a sensitivity and specificity of 74.7% and 60.9%, respectively (p < .0001, AUC = 0.715). HRR however, with a sensitivity and specificity of 67.4% and 68.2% (p < .0001, AUC = 0.718) was the only predictor of CV events following Cox analysis (p < .0001).Conclusions: This study demonstrates MRPP as a poor measure of CV event prediction during DSE. While an APMHR of 89.3% demonstrated a statistically valid model, HRR was the only predictor of CV events in otherwise negative DSEs.

Scientist-led Exercise Testing Is Safe With Diagnostic Interpretation Equivalent to a Cardiologist.

BACKGROUND: The implementation of nonphysician-led exercise stress testing (EST) has increased over the last 30 years, with endorsement by many cardiovascular societies around the world. The comparable safety of nonphysician-led EST to physician-led studies has been demonstrated, with some studies also showing agreement in diagnostic preliminary interpretations. OBJECTIVE: The study aim was to firstly confirm the safety of nonphysician-led EST in a large cohort and secondly compare the interobserver agreement and diagnostic accuracy of cardiac scientist and junior medical officer (JMO)-led EST reports to cardiology consultant overreads. METHODS: All ESTs performed between 1/7/2010 and 30/6/2013 were included in the study for JMO led tests (n = 1332). ESTs performed for the investigation of coronary artery disease between 1/7/2013 and 30/6/2016 were included for scientist-led testing (n = 1904). RESULTS: There was one adverse event, an ST segment myocardial infarction during the recovery phase of a JMO-led EST. Interobserver agreement was superior between the cardiologist and the scientist compared with the cardiologist and the JMO (P < 0.0001). Sensitivity for JMO-led tests differed from the cardiologist overread (86.96% vs. 96.77%, P = 0.03). There were no other significant differences between the cardiologist overread and the JMO- or scientist-led interpretation. CONCLUSIONS: Scientist-led EST is safe in intermediate risk patients and their preliminary reports are equally diagnostic as cardiologist overreads. While JMO-led ESTs are just as safe, the preliminary reports differ significantly from cardiologist overread particularly with respect to sensitivity.

Use of myocardial strain to assess global left ventricular function: a comparison with cardiac magnetic resonance and 3-dimensional echocardiography.

BACKGROUND: Ejection fraction (EF) plays a prominent role in clinical decision making but remains dependent on image quality and left ventricular geometry. Using magnetic resonance imaging (MRI-EF) as the reference standard, we sought whether global longitudinal strain (GLS) could be an alternative to the measurement of EF. METHODS: Manual and semi-automated tracing was used to measure Simpson's biplane ejection-fraction (2D-EF) and 3D ejection fraction (3D-EF) and MRI in 62 patients with previous infarction. Global longitudinal strain was measured by 2-dimensional strain (2DS) in the apical views. Automated EF was calculated using speckle tracking to detect the end-diastolic and end-systolic endocardial border. RESULTS: Strain curves were derived in all segments, with artifactual curves being excluded. The correlation of GLS with MRI-EF (r = -0.69, P < .0001) was comparable to that between 3D-EF and MRI (r = 0.80, P < .0001), and better than that between 2D-EF (r = 0.58, P < .0001) or automated EF and MRI (r = 0.62, P < .0001). To convert GLS into an equivalent MRI-EF, linear regression was used to develop the formula EF = -4.35 (strain + 3.9). Of the 32 patients with a normal MRI-EF (> or =50%), 75% had normal systolic function by GLS, whereas 85% of patients were recognized as having a normal 3D-EF. Fewer patients were recognized as normal by 2D-EF (70%, P = .14) and automated-EF (61%, P = .04). In those with >6 abnormal segments, the correlation of GLS with MRI-EF improved significantly (r = -0.77, P < .0001) and was similar to 3D-EF (r = 0.76, P < .0001). CONCLUSION: Global longitudinal strain is an effective method for quantifying global left ventricular function, particularly in patients with extensive wall motion abnormalities.

Use of myocardial deformation imaging to detect preclinical myocardial dysfunction before conventional measures in patients undergoing breast cancer treatment with trastuzumab.

BACKGROUND: Trastuzumab prolongs survival in patients with human epidermal growth factor receptor type 2-positive breast cancer. Sequential left ventricular (LV) ejection fraction (EF) assessment has been mandated to detect myocardial dysfunction because of the risk of heart failure with this treatment. Myocardial deformation imaging is a sensitive means of detecting LV dysfunction, but this technique has not been evaluated in patients treated with trastuzumab. The aim of this study was to investigate whether changes in tissue deformation, assessed by myocardial strain and strain rate (SR), are able to identify LV dysfunction earlier than conventional echocardiographic measures in patients treated with trastuzumab. METHODS: Sequential echocardiograms (n = 152) were performed in 35 female patients (51 +/- 8 years) undergoing trastuzumab therapy for human epidermal growth factor receptor type 2-positive breast cancer. Left ventricular EF was measured by 2- and 3-dimensional (2D and 3D) echocardiography, and myocardial deformation was assessed using tissue Doppler imaging and 2D-based (speckle-tracking) strain and SR. Change over time was compared every 3 months between baseline and 12 months. RESULTS: There was no overall change in 3D-EF, 2D-EF, myocardial E-velocity, or strain. However, there were significant reductions seen in tissue Doppler imaging SR (P < .05), 2D-SR (P < .001), and 2D radial SR (P < .001). A drop > or =1 SD in 2D longitudinal SR was seen in 18 (51%) patients; 13 (37%) had a similar drop in radial SR. Of the 18 patients with reduced longitudinal SR, 3 had a concurrent reduction in EF > or =10%, and another 2 showed a reduction over 20 months follow-up. CONCLUSIONS: Myocardial deformation identifies preclinical myocardial dysfunction earlier than conventional measures in women undergoing treatment with trastuzumab for breast cancer.

Baseline and follow-up assessment of regional left ventricular volume using 3-Dimensional echocardiography: comparison with cardiac magnetic resonance.

The assessment of regional volumes is an option for analysis of the response of LV segments to interventions such as revascularization or cell therapy. We sought to compare regional volumes from 3D-echocardiography (3DE) with cardiac magnetic resonance (CMR) over follow-up. CMR regional volumes were assessed at baseline and after one year follow-up in 30 unselected patients (28 men, 65 +/- 11 years) presenting for evaluation of cardiac function with previous infarction. 3DE images were also gathered over 4 cardiac cycles and measurements were performed off-line. CMR images were obtained using a 1.5 Tesla scanner and measured offline by method of landmarks and by centre of mass. Regional volumes were measured at end-diastole (rEDV) and end-systole (rESV) and the change in volume was compared for each over follow-up. There was good correlation between 3DE and both CMR methods at baseline and follow-up. Changes in rEDV with 3DE vs CMR(L) were comparable (0.11 +/- 3 ml vs 0.12 +/- 3 ml, p = 0.94), as was change in CMR(M) (0.26 +/- 2 ml, p = 0.69). However the change in regional volume by 3DE and CMR(L) correlated poorly (r = 0.03, p = 0.68), as did change in 3DE vs CMR(M) (r = 0.04, p = 0.65). Similarly, changes in rESV with 3DE and CMR(L) were similar (0.27 +/- 2 ml vs 0.36 +/- 2 ml, p = 0.70), as was change in CMR(M) (0.05 +/- 1 ml, p = 0.31). Again, correlations between rESV by 3DE vs CMR(L) were poor (r = 0.03, p = 0.72), as well as 3DE vs CMR(M) (r = 0.07, p = 0.40). Although global 3DE volumes compare well with CMR volumes, new developments in image quality and automated software will be needed before changes in regional volumes can be reliably followed with 3DE.

Is downstream cardiac testing required in patients with reduced functional capacity and otherwise negative exercise stress test? A single center observational study.

BACKGROUND: Exercise stress testing (EST) in patients with poor functional capacity measured by time on treadmill is typically deemed inconclusive and usually leads to further downstream testing. The aim of this study was firstly to evaluate the maximum rate pressure product (MRPP) during initial EST to assessthe need for follow-up testing; and secondly to investigate if MRPP is better than age predicted maximum heart rate (APMHR) for diagnostic outcome based on follow up cardiovascular (CV) events in patients with inconclusive EST due to poor functional capacity. METHODS: From a total of 2761 tests performed, 236 tests were considered inconclusive due to poor functional capacity which were available for analysis. From receiver operating characteristic (ROC) analysis, a cut-off value for MRPP of 25000 was chosen using CV events as the outcome measure (sensitivity 97%, specificity 45%). Cases were then categorised into those with an MRPP > 25000 and < 25000. RESULTS: Regardless of treadmill time, any patient attaining an MRPP > 25000 had no abnormal downstream testing or CV events at 2 years follow-up. On ROC analysis MRPP outperformed APMHR for sensitivity and specificity (area under curve 0.76 vs. 0.59, respectively). CONCLUSIONS: The results suggest that regardless of functional capacity, individuals whose EST is terminated at maximal fatigue, with no electrocardiogram evidence or symptoms of myocardial ischemia and yields an MRPP > 25000, do not require further downstream testing. Furthermore, this group of patients, while not immune to future CV events, have significantly better outcomes than those not attaining a MRPP > 25000.

Handrail support produces a higher rate pressure product in apparently healthy non-treadmill users during maximal exercise testing.

OBJECTIVE: Exercise treadmill testing (ETT) is a well-established procedure for the diagnosis, prognosis and functional assessment of patients with suspected cardiovascular disease. The use of handrail support during ETT is often discouraged as this has been demonstrated to overestimate functional capacity. It is unknown if this increase in functional capacity translates to an increase in cardiac workload. The aim of this study was to investigate if the use of handrail support during maximal ETT produces an increase in cardiac workload when compared to no handrail support. APPROACH: Fifty-two consenting volunteers performed two maximal ETTs, one with handrail support and the other without, approximately one week apart. Participants were identified as either experienced treadmill users (treadmill use ⩾ once per fortnight) (n = 24) or inexperienced users (n = 28). Cardiac workload was quantified using rate pressure product (RPP) (systolic blood pressure (SBP) × heart rate (HR)) Main results: The average age of participants was 38.4 ± 11.4 years (44% male). Overall exercise duration was significantly prolonged by 44.4% with handrail support (with support 15:01 ± 2:54 min; without support 10:24 ± 2:09 min). Overall HR, SBP and maximum RPP were not significantly different between conditions. For the 28 inexperienced treadmill users maximum RPP was significantly higher during handrail support (7.5% increase) (with support 34 417 ± 4906; without support 31 821 ± 4565). SIGNIFICANCE: Handrail support overestimates functional capacity, however produces greater maximal RPP in inexperienced treadmill users. If accurate aerobic data is required during ETT, or subjects performing ETT are experienced treadmill users, handrail support should be discouraged. Non-treadmill users or subjects fearful of falling may benefit from handrail support, particularly when maximal cardiac workload is desired.

Comparison of Heart Rate Blood Pressure Product Versus Age-Predicted Maximum Heart Rate as Predictors of Cardiovascular Events During Exercise Stress Echocardiography.

Exercise stress echocardiograms (ESEs) are a functional cardiovascular (CV) test typically used for the investigation of coronary artery disease. ESEs are often terminated at a predetermined age-predicted maximum heart rate (APMHR) to facilitate timely acquisition of ultrasound images at peak exercise. Although an APMHR of 85% is often used, this has not been validated as a suitable termination end point. Heart rate blood pressure product (HRBPP) as an established measure of myocardial work may provide a more reliable assessment of cardiac workload. The aim of this study was to assess maximal HRBPP (MHRBPP) and APMHR as markers of cardiac workload during ESE, using CV events at mean follow-up as the outcome variable. After exclusions, 712 patients being investigated for ischemic heart disease, performed an ESE to volitional fatigue using the standard Bruce protocol. Patient demographics and test data were collected and patients followed for 4.4 ± 2.1 years. Cut-points for MHRBPP (25,060; area under curve 0.77) and APMHR (93.8% and 97.9%; area under curve 0.71; p = 0.12 for difference) were established from receiver operating characteristic analysis. Those achieving an APMHR >85% but MHRBPP <25,060 had significantly more CV events than achieving an MHRBPP >25,060 regardless of APMHR (p <0.05). In conclusion, the current study demonstrates the superior prognostic power of MHRBPP over APMHR alone for the prediction of future CV events in patients performing an otherwise negative ESE for the detection of myocardial ischemia.

An intensive interactive course for 3D echocardiography: is 'crop till you drop' an effective learning strategy?

BACKGROUND: Three-dimensional echocardiography (3DE) appears to show incremental benefit over two-dimensional echocardiography (2DE), but it's uptake has been slow. We tested attendees before and after an intensive interactive training course to identify its efficacy. METHODS: Attendees (n = 35, 23 cardiologists, 12 sonographers) were shown how to use 3DE review software and asked to identify the pathology of five patients (wall motion abnormality, peri-prosthetic mitral regurgitation, subaortic membrane, small ventricular septal defect, submitral stenosis) on 2D and 3D images. In the following one and a half-day interactive teaching course, brief presentations on application of 3DE for assessment of wall motion, valve and congenital abnormalities were followed by review of 3D datasets, during which the attendees made their own interpretations before being shown the optimal viewing strategy. Test cases were not discussed and the test was repeated at the end of the course. RESULTS: Most attendees (57%) had access but with little or no use of a 3DE system. Three-dimensional echocardiography had no incremental value before training. After training, overall correct responses significantly improved compared with baseline interpretation, although improvement was not the same for all diagnoses. All groups (cardiologists vs. sonographers, inexperienced vs. moderately experienced reviewers) improved similarly. CONCLUSIONS: Incorporation of 3DE into standard practice may be limited by inexperience. An interactive teaching course with rehearsal and direct mentoring appears to overcome this limitation and may improve the uptake of this technique.

Left ventricular opacification for the diagnosis of coronary artery disease with stress echocardiography: an angiographic study of incremental benefit and cost-effectiveness.

BACKGROUND: Left ventricular opacification (LVO) improves image quality at stress echocardiography (SE). We examined whether routine use of LVO adds incremental benefit and is cost-effective for diagnosis of coronary artery disease (CAD). METHODS: Contrast pharmacologic and/or exercise SE was performed in 135 patients (81 men; 56 +/- 10 years) undergoing coronary angiography. Observers sequentially interpreted first standard, then LVO images; a positive SE was defined by resting or inducible wall motion abnormality in > or = 2 segments. Coronary artery disease (75 patients, 119 territories) was defined as > 50% stenosis. Three cost-effectiveness models were studied, and a sensitivity analysis was performed. RESULTS: Left ventricular opacification increased the sensitivity of SE (80%-91%; P = .03), including single-vessel CAD (65%-87%; P = .04), with no significant change in specificity (72%-77%; P = NS). Left ventricular opacification was of benefit to 14% of patients, unrelated to resting image quality. Use of LVO in all patients added 59% to the cost of the procedure (P < .001), at a cost of $1069 per additional correct diagnosis. In a cost-effectiveness model based on cardiac outcomes after SE, LVO resulted in an increase in total cost of $1069. A 3.7% improvement in sensitivity resulted in a negative cost to identify CAD, but even 15% to 20% improvements in specificity failed to balance the cost of contrast for exclusion of CAD. CONCLUSIONS: Left ventricular opacification adds significant incremental diagnostic benefit to standard SE, especially single-vessel CAD. Despite improved sensitivity, the use of contrast in all patients was not cost-effective when analyzed with a model based on previously published patient outcomes.

Comparison of two- and three-dimensional echocardiography with sequential magnetic resonance imaging for evaluating left ventricular volume and ejection fraction over time in patients with healed myocardial infarction.

Echocardiographic follow-up of left ventricular (LV) volumes is difficult because of the test-retest variation of 2-dimensional echocardiography (2DE). We investigated whether the accuracy and reproducibility of real-time 3-dimensional echocardiography (RT3DE) would make this modality more feasible for serial follow-up of LV measurements. We performed 2DE and RT3DE and cardiac magnetic resonance imaging (MRI) in 50 patients with previous infarction and varying degrees of LV function (44 men; 61 +/- 11 years of age) at baseline and after 1-year follow-up. Images were obtained during breath-hold and measurements of LV volumes and ejection fraction were made offline. Over follow-up, end-diastolic volume decreased from 192 +/- 53 to 187 +/- 60 ml (p <0.01), end-systolic volume decreased from 104 +/- 51 to 95 +/- 53 ml (p <0.01), and ejection fraction increased from 48 +/- 12% to 51 +/- 12% (p <0.01). MRI showed that LV mass shrank from 183 +/- 39 to 182 +/- 37 g (p <0.01). The correlation between change in RT3DE and change in MRI was greater than the correlations of 2DE with MRI for measurement of end-diastolic volume (r = 0.47 vs 0.02, p <0.01), end-systolic volume (r = 0.44 vs 0.17, p <0.01), and ejection fraction (r = 0.58 vs -0.03, p <0.01). The change in end-diastolic volume between baseline and follow-up with RT3DE (-4 +/- 20, p <0.01) was similar to that with MRI but was unrecognized by 2DE (4 +/- 19, p = 0.09). There was good test-retest and inter- and intraobserver correlation within RT3DE for volumes, ejection fraction, and mass. In conclusion, if sequential measurement of LV volumes is used to guide management decisions, 3DE appears preferable to 2DE.

Reproducibility of right ventricular volumes and ejection fraction using real-time three-dimensional echocardiography: comparison with cardiac MRI.

OBJECTIVES: The nongeometric nature of the right ventricle (RV) makes it difficult to measure. We sought to determine whether real-time three-dimensional echocardiography (RT3DE) is superior to two-dimensional echocardiography (2DE) for the follow-up of RV function by validation vs cardiac MRI. METHODS: RV volumes and ejection fraction (EF) were studied with 2DE (including area-length [A-L], the modified two-dimensional subtraction [2DS] method, and the Simpson method of discs), RT3DE, and MRI in 50 patients with left ventricular wall motion abnormalities, the results of which suggested possible RV infarction. Test-retest variation was performed by a complete restudy using a separate sonographer within 24 h without the alteration of hemodynamics or therapy. Interobserver and intraobserver variations were noted in a subgroup of 20 patients. RESULTS: EF estimations were similar using each technique. The mean (+/- SD) MRI end-diastolic volume (87 +/- 22 mL) was only slightly underestimated by RT3DE (mean difference, -3 +/- 10; p < 0.05), with a greater mean difference for 2DE A-L (-29 +/- 10; p < 0.05), and the Simpson method of discs (-29 +/- 23; p < 0.05), and was greatly overestimated by 2DS (mean difference, 26 +/- 23; p < 0.05). Similarly, the mean MRI end-systolic volume (46 +/- 17 mL) was only slightly underestimated by RT3DE (-4 +/- 7; p < 0.05), compared with 2DE A-L (-16 +/- 8; p < 0.05) and the Simpson method of discs (-16 +/- 8; p < 0.05), and was overestimated by 2DS (14 +/- 13; p < 0.05). RT3DE findings had a higher correlation with each parameter than any 2DE technique. There was also good intraobserver and interobserver correlation between RT3DE by two sonographers. RT3DE had less test-retest variation of RV volumes and EF than any 2DE measure. CONCLUSIONS: RT3DE is more accurate than two-dimensional approaches and reduces the test-retest variation of RV volumes and EF measurements in follow-up RV assessment.