A clinical pathway for heart failure reduces admissions from the ED without increasing congestion in the ED.

BACKGROUND: A multidisciplinary team at a major academic medical center established an Acutely Decompensated Heart Failure Clinical Pathway (ADHFCP) program to reduce inpatient readmission rates among patients with heart failure which, among several interventions, included an immediate consultation from a cardiologist familiar with an ADHFCP patient when the patient presented at the Emergency Department (ED). This study analyzed how that program impacted utilization of services in the ED and its subsequent effect on rates of admission from the ED and on disposition times. METHODS: ADHFCP inpatient visits were retrospectively risk stratified and matched with non-program inpatient visits to create a control group. A Cox survival model analyzed the ADHFCP's impact on patients' likelihood to visit the ED. Multivariable ANOVA evaluated the impact of the program on the patients' likelihood of being admitted when presenting at the ED. The ADHFCP's impact on bed-to-disposition time in the ED was evaluated by Wilcoxon's rank-sum test, as were doses of diuretics administered in the ED. RESULTS: The survival analysis showed no impact of the ADHFCP on patients' likelihood of visiting the ED, but ADHFCP patients presenting to the ED were 13.1 (95% CI: 3.6-22.6) percentage points less likely to be admitted. There was no difference in bed-to-disposition times, but ADHFCP patients received diuretics more frequently and at higher doses. CONCLUSIONS: Improved communication between cardiologists and ED physicians through the establishment of an explicit pathway to coordinate the care of heart failure patients may decrease that population's likelihood of admission without increasing ED disposition times.

Focused cardiac ultrasound: where do we stand?

Focused cardiac ultrasound (FCU) is a bedside examination of the heart performed with a small, portable ultrasound platform by a physician as an adjunct to their physical examination. The goal is to recognize a narrow list of abnormalities that are both detectable by physicians with limited ultrasound training and have high clinical assessment value. Results from the FCU examination are integrated with traditional bedside assessment (physical examination and history) to provide early management plans and patient triage in settings when echocardiography cannot be obtained or is not immediately available.

Use of hand carried ultrasound, B-type natriuretic peptide, and clinical assessment in identifying abnormal left ventricular filling pressures in patients referred for right heart catheterization.

BACKGROUND: The estimation of left ventricular filling pressure (LVFP) remains a critical component in the management of patients with known or suspected acute heart failure syndromes. Although right heart catheterization (RHC) remains the gold standard, several noninvasive parameters, including clinical assessment, B-type natriuretic peptides (BNP), and echocardiography can approximate LVFP. We sought to use a combination of these measures to noninvasively predict high or low LVFP in a population referred for RHC. METHODS AND RESULTS: The study consisted of validation of hand-carried ultrasound (HCU)-derived measurement of mitral E/E' against standard echocardiograms in 50 patients, as well as direct comparison of jugular venous pressure (JVP), a clinical congestion score, HCU-derived E/E' and maximum inferior vena cava diameter (IVCmax), and BNP with pulmonary capillary wedge pressure (PCWP) in another 50 patients. The mean age was 61 years, ejection fraction 40%, JVP 9 cm, BNP 948 pg/mL, IVCmax 2.1 cm, E/E' 13, and PCWP 21. All parameters performed well in determining PCWP >or=15 mm Hg, with clinical score performing the worst (area under the receiver-operator characteristic curve [AUC] 0.74), and IVCmax performing the best (AUC 0.89). JVP, in combination with HCU-derived parameters and BNP performed better than any of the individual tests alone (AUC 0.97 for combination of all 3). CONCLUSIONS: Clinical score, JVP, HCU indices, and BNP perform well at identifying patients with a PCWP >or=15 mm Hg. Use of these indices alone or in combination can be used to identify and potentially monitor patients with high LVFP in the inpatient and outpatient settings.

Handcarried echocardiography to assess hemodynamics in acute decompensated heart failure.

Heart failure is a major source of cardiovascular morbidity, including acute decompensations requiring hospitalization. Because most therapeutic interventions in acute heart failure target optimization of cardiac output and volume status, accurate assessment of these parameters at the point of care is critical to guide management. However, physician bedside assessments of left ventricular (LV) function and volume status have limited accuracy. Traditional echocardiographic platforms, while useful for assessing ventricular and valvular function and volume status, have limitations for bedside use or frequent serial evaluation. Handcarried cardiac ultrasound devices, with their substantially lower costs, portability, and ease of use, circumvent many of the limitations of traditional echocardiographic platforms. The diagnostic capabilities of handcarried devices provide the opportunity for ultrasound assessment of LV function and serial bedside evaluation of volume status in patients with acutely decompensated heart failure.

Focused Cardiac Ultrasonography.

Focused cardiac ultrasonography (FCU) is the use of ultrasonography as an adjunct to physical examination at the point of care. There are ample data supporting the fact that noncardiology trained users using small ultrasonography devices can assess left ventricular (LV) enlargement, LV systolic dysfunction, right ventricular (RV) enlargement, left atrial (LA) enlargement, LV hypertrophy, pericardial effusion, and right atrial (RA) pressure elevation more accurately than performing a physical examination. In addition, FCU-trained providers may have skills to perform ultrasonography imaging of body systems outside the heart to supplement their cardiac evaluation. FCU training, including didactic education, proctored imaging, independent imaging, and image interpretation, has been established by several specialties and medical schools. Cardiologists should embrace FCU in their facilities, as the clinical value to patient care is clear. Cardiologists have the responsibility to maintain excellence in the practice of echocardiography while enabling the use of ultrasonography by other medical professionals to augment their clinical assessments conventionally based on physical examination alone.

Hand carried echocardiography screening for LV systolic dysfunction in a pulmonary function laboratory.

AIMS: Dyspnea is a common indication for pulmonary evaluation but also a common symptom in heart failure. Identification of dyspneic patients with significant LV systolic dysfunction is critical because of high morbidity of untreated heart failure. We sought to determine whether screening patients referred for pulmonary function testing (PFT) using a hand carried ultrasound (HCU) device could identify LV systolic dysfunction. METHODS: Forty-nine subjects were recruited from a pulmonary function lab to undergo a brief echocardiographic examination by an internist using a HCU device. All subjects also received an examination with a full-featured echocardiogram machine as a gold standard. RESULTS: All subjects with normal PFT had normal LV systolic function. Among subjects with abnormal PFT, 6 (15%) had LV systolic dysfunction and the remainder had normal LV systolic function. No subjects with LV systolic dysfunction by full-featured echocardiograms were missed by the HCU (sensitivity 100%, specificity 95%, negative predictive value 100%, positive predictive value 75%). CONCLUSIONS: LV systolic dysfunction is prevalent among patients with pulmonary disease and can be accurately screened for by a physician using a hand carried ultrasound device with subsequent confirmation with complete echocardiography.

Focused cardiac ultrasound as a predictor of readmission in acute decompensated heart failure.

Acute decompensated heart failure (ADHF) is a common reason for admission to the hospital, and readmission is frequent. Multiple factors contribute to rehospitalizations, but inadequate assessment of volume status leading to persistent congestion is an important factor. We sought to determine if focused cardiac ultrasound (FCU) of the inferior vena cava (IVC), as a surrogate of volume status, would predict readmission of ADHF patients after index hospitalization. Patients admitted with a primary diagnosis of ADHF were prospectively enrolled. All patients underwent FCU of the IVC on admission and then daily. 82 patients were enrolled. Patients demonstrated improvement in heart failure physical examination findings and symptoms during the hospitalization. There was a reduction in the size of the IVC and a significant increase in patients with small collapsible vena cava. Logistic regression analysis of physical examination, patient symptoms, and IVC parameters at discharge demonstrated IVC collapsibility and patient reported dyspnea improvement as the only significant variables to predict readmission or emergency department visit. FCU assessment of IVC size and collapsibility may be useful in patients with ADHF to predict risk of being readmitted within 30 days of hospital discharge.

2D and 3D Echocardiography-Derived Indices of Left Ventricular Function and Shape: Relationship With Mortality.

OBJECTIVES: This study hypothesized that left ventricular (LV) ejection fraction (EF) and global longitudinal strain (GLS) derived from 3-dimensional echocardiographic (3DE) images would better predict mortality than those obtained by 2-dimensional echocardiographic (2DE) measurements, and that 3DE-based LV shape analysis may have added prognostic value. BACKGROUND: Previous studies have shown that both LVEF and GLS derived from 2DE images predict mortality. Recently, 3DE measurements of these parameters were found to be more accurate and reproducible because of independence of imaging plane and geometric assumptions. Also, 3DE analysis offers an opportunity to accurately quantify LV shape. METHODS: We retrospectively studied 416 inpatients (60 ± 18 years of age) referred for transthoracic echocardiography between 2006 and 2010, who had good-quality 2DE and 3DE images were available. Mortality data through 2016 were collected. Both 2DE and 3DE images were analyzed to measure LVEF and GLS. Additionally, 3DE-derived LV endocardial surface information was analyzed to obtain global shape indices (sphericity and conicity) and regional curvature (anterior, septal, inferior, lateral walls). Cardiovascular (CV) mortality risks related to these indices were determined using Cox regression. RESULTS: Of the 416 patients, 208 (50%) died, including 114 (27%) CV-related deaths over a mean follow-up period of 5 ± 3 years. Cox regression revealed that age and body surface area, all 4 LV function indices (2D EF, 3D EF, 2D GLS, 3D GLS), and regional shape indices (septal and inferior wall curvatures) were independently associated with increased risk of CV mortality. GLS was the strongest prognosticator of CV mortality, superior to EF for both 2DE and 3DE analyses, and 2D EF was the weakest among the 4 functional indices. A 1% decrease in GLS magnitude was associated with an 11.3% increase in CV mortality risk. CONCLUSIONS: GLS predicts mortality better than EF by both 3DE and 2DE analysis, whereas 3D EF is a better predictor than 2D EF. Also, LV shape indices provide additional risk assessment.

A comparison by medicine residents of physical examination versus hand-carried ultrasound for estimation of right atrial pressure.

Physicians' ability to accurately estimate right atrial (RA) pressure from bedside evaluation of the jugular venous waveform is poor, particularly when performed by physicians in training. Conventional ultrasound measurement of the inferior vena cava (IVC) accurately predicts RA pressure, but the cost, lack of portability, and specialized training required to acquire and interpret the data render this modality impractical for routine clinical use. The objective of this study was to compare physical examination with hand-carried ultrasound (HCU) in the detection of elevated RA pressure (>10 mm Hg). After limited training (4 hours didactic and 20 studies), 4 internal medicine residents using an HCU device estimated RA pressure from images of the IVC in 40 consecutive patients <1 hour after right-sided cardiac catheterization. RA pressure was also estimated from examination of the jugular venous pulse (JVP) in 40 patients before right-sided cardiac catheterization. RA pressure was successfully estimated from HCU images of the IVC in 90% of patients, compared with 63% from JVP examination. The sensitivity for predicting RA pressure >10 mm Hg was 82% with HCU and 14% from JVP inspection. Specificities were similar between the techniques. Overall accuracies were 71% using HCU and 60% with JVP assessment. In conclusion, internal medicine residents with brief training in echocardiography can more frequently and more accurately predict elevated RA pressure using HCU measurements of the IVC than with physical examination of the JVP.

Radial artery pulse pressure variation correlates with brachial artery peak velocity variation in ventilated subjects when measured by internal medicine residents using hand-carried ultrasound devices.

BACKGROUND: Rapid prediction of the effect of volume expansion is crucial in unstable patients receiving mechanical ventilation. Both radial artery pulse pressure variation (DeltaPP) and change of aortic blood flow peak velocity are accurate predictors but may be impractical point-of-care tools. PURPOSES: We sought to determine whether respiratory changes in the brachial artery blood flow velocity (DeltaVpeak-BA) as measured by internal medicine residents using a hand-carried ultrasound (HCU) device could provide an accurate corollary to DeltaPP in patients receiving mechanical ventilation. METHODS: Thirty patients passively receiving volume-control ventilation with preexisting radial artery catheters were enrolled. The brachial artery Doppler signal was recorded and analyzed by blinded internal medicine residents using a HCU device. Simultaneous radial artery pulse wave and central venous pressure recordings (when available) were analyzed by a blinded critical care physician. RESULTS: A Doppler signal was obtained in all 30 subjects. The DeltaVpeak-BA correlated well with DeltaPP (r = 0.84) with excellent agreement (weighted kappa, 0.82) and limited intraobserver variability (2.8 +/- 2.8%) [mean +/- SD]. A DeltaVpeak-BA cutoff of 16% was highly predictive of DeltaPP > or = 13% (sensitivity, 91%; specificity, 95%). A poor correlation existed between the CVP and both DeltaVpeak-BA (r = - 0.21) and DeltaPP (r = - 0.16). CONCLUSIONS: The HCU Doppler assessment of the DeltaVpeak-BA as performed by internal medicine residents is a rapid, noninvasive bedside correlate to DeltaPP, and a DeltaVpeak-BA cutoff of 16% may prove useful as a point-of-care tool for the prediction of volume responsiveness in patients receiving mechanical ventilation.

Myocardial strain may be useful in differentiating Takotsubo cardiomyopathy from left anterior descending coronary artery ischemia.

BACKGROUND: Stress-induced cardiomyopathy (SCM) is characterized by transient apical wall motion abnormalities of the left ventricle (LV) in the absence of obstructive coronary artery disease. Although the echocardiographic findings of SCM mimic those of left anterior descending coronary artery ischemia or infarction (LAD), the regional LV wall motion pattern and degree of RV involvement may differ. METHODS: We sought to systematically assess regional LV and RV function with myocardial strain imaging to assess if ventricular involvement may differ between SCM and LAD. RESULTS: This was a retrospective cohort study, with 3 groups: patients with SCM (n=55), patients with LAD (n=36), and 37 normal subjects. All the patients had a comprehensive transthoracic echocardiographic examination, including assessment of longitudinal strain (LS). Global LV longitudinal strain was markedly decreased in both the SCM and LAD groups. However, SCM patients differed by more severe involvement the mid-inferolateral, mid-inferior, apical-lateral, and apical-inferior segments. When compared to the LAD patients, SCM patients had significantly more RV involvement both visually and quantitatively (27-42% versus 0-25%). Predictors of SCM included visually reduced RV systolic function, abnormal TAPSE, RVS' and RV LS in the apical segment. Of the LV variables, regional LS in the mid-inferior and apical-inferior segments could differentiate the groups. CONCLUSIONS: Our results suggest that RV involvement and the pattern of LV regional LS abnormalities may help differentiate SCM from LAD disease during echocardiographic imaging.

Cardiology Consultation in the Emergency Department Reduces Re-hospitalizations for Low-Socioeconomic Patients with Acute Decompensated Heart Failure.

BACKGROUND: Re-hospitalization after discharge for acute decompensated heart failure is a common problem. Low-socioeconomic urban patients suffer high rates of re-hospitalization and often over-utilize the emergency department (ED) for their care. We hypothesized that early consultation with a cardiologist in the ED can reduce re-hospitalization and health care costs for low-socioeconomic urban patients with acute decompensated heart failure. METHODS: There were 392 patients treated at our center for acute decompensated heart failure who received standardized education and follow-up. Patients who returned to the ED received early consultation with a cardiologist; 392 patients who received usual care served as controls. Thirty- and 90-day re-hospitalization, ED re-visits, heart failure symptoms, mortality, and health care costs were recorded. RESULTS: Despite guideline-based education and follow-up, the rate of ED re-visits was not different between the groups. However, the rate of re-hospitalization was significantly lower in patients receiving the intervention compared with controls (odds ratio 0.592), driven by a reduction in the risk of readmission from the ED (0.56 vs 0.79, respectively). Patients receiving the intervention accumulated 14% fewer re-hospitalized days than controls and 57% lower 30-day total health care cost. Despite the reduction in health care resource consumption, mortality was unchanged. After accounting for the total cost of intervention delivery, the health care cost savings was substantially greater than the cost of intervention delivery. CONCLUSION: Early consultation with a cardiologist in the ED as an adjunct to guideline-based follow-up is associated with reduced re-hospitalization and health care cost for low-socioeconomic urban patients with acute decompensated heart failure.

Overestimation of postischemic myocardial stunning on gated SPECT imaging: correlation with echocardiography.

BACKGROUND: Postischemic global and regional left ventricular (LV) dysfunction on stress-gated single photon emission computed tomography (SPECT) imaging is attributed widely to myocardial stunning. We sought to determine the specificity of gated SPECT for the detection of myocardial stunning after ischemic stress. METHODS AND RESULTS: Twenty-seven patients with an ischemic response to stress on dual-isotope exercise SPECT were enrolled prospectively. Transthoracic echocardiography was performed just before stress gated SPECT for assessment of regional wall motion and quantitative LV ejection fraction (LVEF). The 17 myocardial segments for each patient were scored for myocardial perfusion by stress gated SPECT, and regional wall motion by stress gated SPECT and echo. Of the 459 myocardial segments, 41% had perfusion defects, 15% had stress gated SPECT regional wall motion abnormality, 4.8% had poststress echo regional wall motion abnormality, and 3.9% had baseline regional wall motion abnormality. Overall, a stress gated SPECT regional wall motion abnormality had a sensitivity of 100% and a specificity of 89%. Among reversible perfusion defects of moderate severity or more, a stress gated SPECT regional wall motion abnormality had a specificity of 41% and a positive predictive value of 8%. Stress gated SPECT LVEF was similar to poststress echo LVEF for all patients, but significantly lower in patients with reversible perfusion defects of moderate severity or more. CONCLUSION: Post-stress gated SPECT imaging overestimates global and regional myocardial stunning. Caution should be exercised in interpreting poststress global or regional LV function on stress gated SPECT in scans with reversible ischemia.

Rapid assessment of left ventricular systolic function in a pacemaker clinic using a hand-carried ultrasound device.

OBJECTIVE: Pacemaker recipients with left ventricular (LV) dysfunction are potential candidates for upgrades to implantable defibrillators or cardiac resynchronization devices. This study sought to determine if a hand-carried ultrasound (HCU) device could be used for rapid, inexpensive identification of LV dysfunction in a busy pacemaker clinic. MATERIALS AND METHODS: Eighty patients undergoing routine pacemaker check were enrolled. Patients underwent HCU imaging in the sitting position during device interrogation, by an internist who had 20 h of didactic training and 20 practice examinations. LV dysfunction was defined as ejection fraction (EF) <40%. Patients also underwent echocardiography limited to EF assessment by a sonographer using a full-feature platform. RESULTS: The mean age was 75 +/- 13 years; 49% were female. Coronary artery disease was present in 29%; 82% were NYHA class I or II. At the time of HCU imaging, 48% of patients were receiving RV pacing. HCU images were interpretable in 91% (73/80) and required 3.7 +/- 0.9 min to complete. Based on the full-feature echo, LV dysfunction prevalence was 17/80 (21%); 25% of these patients were NYHA class I. The sensitivity of the HCU exam was 75%, specificity was 91%, negative predictive value was 93%, positive predictive value was 71%, and accuracy was 88%. CONCLUSIONS: HCU screening in a pacemaker clinic by a non-cardiologist can rapidly and accurately identify pacemaker recipients with at least moderate LV dysfunction who might be candidates for device upgrades. Ventricular dyssynchrony associated with RV pacing does not limit HCU identification of LV dysfunction.

Monitoring Ionizing Radiation Exposure for Cardiotoxic Effects of Breast Cancer Treatment.

Serial assessments of left ventricular ejection fraction (LVEF) are customary in patients with breast cancer receiving trastuzumab. Radionuclide angiography (RNA) is often used; however, a typical monitoring schedule could include 5 scans in a year. We evaluated the proportion of imaging-related ionizing radiation attributable to RNA in 115 patients with breast cancer, from 3 medical centers in the United States, Ireland, and Japan, who completed 12 months of trastuzumab treatment. Estimated radiation dose (ERD) was used to calculate exposure associated with imaging procedures spanning the 18 months before and after trastuzumab therapy. In addition, 20 cardiologists and oncologists from participating centers were surveyed for their opinions regarding the contribution of RNA to overall radiation exposure during trastuzumab treatment. When RNA was used to monitor LVEF, the mean ERD from imaging was substantial (34 ± 24.3 mSv), with the majority attributable solely to RNA (24.7 ± 14.8 mSv, 72.6%). Actual ERD associated with RNA in this population differed significantly from the perception in surveyed cardiologists and oncologists; 70% of respondents believed that RNA typically accounted for 0% to 20% of overall radiation exposure from imaging; RNA actually accounted for more than 70% of ERD. In conclusion, RNA was used to monitor LVEF in most patients in this cohort during and after trastuzumab therapy. This significantly increased ERD and accounted for a greater proportion of radiation than that perceived by surveyed physicians. ERD should be taken into account when choosing a method of LVEF surveillance. Alternative techniques that do not use radiation should be strongly considered.

Differential diagnosis of cardiac masses using contrast echocardiographic perfusion imaging.

OBJECTIVES: We investigated the usefulness of echocardiographic contrast perfusion imaging in differentiating cardiac masses. BACKGROUND: Two-dimensional echocardiography is the primary diagnostic modality for cardiac masses. However, differentiation between the different types of cardiac masses may be difficult at times. We hypothesized that echocardiographic contrast perfusion imaging would differentiate the neo-vascularization of malignancies from the avascularity of thrombi and the sparse vascularity of stromal tumors. METHODS: Sixteen patients with cardiac masses underwent power-modulation imaging after echocardiographic intravenous contrast administration. Pixel intensities in the mass and an adjacent section of myocardium were analyzed visually and by dedicated software. All masses had a pathologic diagnosis or resolved after anticoagulation. In a subset of patients, video-intensity curves of contrast replenishment in the mass and myocardium over time were generated. The post-impulse steady-state pixel intensity (A) and initial rate of contrast replenishment after impulse (beta) were compared with an index of blood vessel area on pathology. RESULTS: In seven of 16 patients, contrast enhancement resulted in greater pixel intensity in the mass than in the adjacent myocardium. All of these masses were classified pathologically as malignant (n = 6) or benign and vascular (n = 1). Nine masses demonstrated decreased pixel intensity, compared with the myocardium, and were diagnosed pathologically as myxomas (n = 2) or thrombi (n = 5), or they resolved with anticoagulation (n = 2). For the subset of patients, beta correlated with the vessel area index (r = 0.60). CONCLUSIONS: Echocardiographic contrast perfusion imaging aids in the differentiation of cardiac masses. Compared with the adjacent myocardium, malignant and vascular tumors hyper-enhanced, whereas stromal tumors and thrombi hypo-enhanced.

Effectiveness of echocardiographic imaging by nurses to identify left ventricular systolic dysfunction in high-risk patients.

Recognizing left ventricular (LV) systolic dysfunction is critical. The investigators sought to evaluate whether nurses could be trained to use a hand-carried ultrasound (HCU) device to screen for LV systolic dysfunction in high-risk patients. Sixty-three patients from an outpatient diabetes clinic underwent brief echocardiographic examinations by nurses using HCU devices. Of the 63 patients enrolled in the study, 3 (4.7%) had LV systolic dysfunction. The nurses correctly identified these 3 patients as having LV systolic dysfunction (sensitivity 100%, negative predictive value 100%). The identification of occult LV systolic dysfunction in diabetic patients may allow the initiation of therapies known to improve prognosis.

Use of hand-carried ultrasound devices to augment the accuracy of medical student bedside cardiac diagnoses.

BACKGROUND: Hand-carried ultrasound (HCU) devices used by cardiologists as extensions of the physical examination have been shown to improve the accuracy of bedside diagnoses. We tested the feasibility of teaching medical students to use HCU devices to make bedside cardiac diagnoses and compared the accuracy of their HCU and physical examinations. METHODS: In all, 10 fourth-year medical students enrolled in a 4-week medical school course on the cardiac examination. Students examined 12 standardized patients at 3 different time intervals: (1) on day 1 of the course; (2) on day 10 after review of cardiac physical examination using traditional teaching methods; and (3) after instruction on the use of HCU devices. Students were scored at each time interval for primary findings (most salient) and all findings, accounting for both errors of commission and omission. Scores could range from +12 to -12 for primary findings and from +22 to -22 for all findings. A perfect score was +12 for primary findings and +22 for all findings. RESULTS: The average score for all students at baseline was -3.2 +/- 3.1 and -5.7 +/- 4.8 for primary and all findings, respectively. A significant improvement in the scores was noted with use of the HCU device (2.6 +/- 3.1 and 5.2 +/- 6.6 for primary and all findings, respectively) compared with the baseline and two subsequent physical examinations. CONCLUSION: Instruction of fourth-year medical students on the use of HCU device is feasible and results in significantly more accurate bedside diagnoses.

Automated border detection on contrast enhanced echocardiographic images.

BACKGROUND: Accurate determination of left ventricular ejection fraction (LV EF) is of paramount importance in the evaluation of patients with cardiovascular disease. Quantitative techniques for the automated calculation of EF exist however, the robustness of these techniques is dependent on adequate endocardial border definition and therefore are difficult to use in patients with limited images. We sought to combine the endocardial border enhancing effects of contrast echocardiography with an automated border detection technique to provide quantitative and accurate determination of LV EF. METHODS: Thirty-nine consecutive patients referred to nuclear cardiology for EF determination underwent radionuclide angiography followed by echocardiographic imaging using prototype software that allowed automated border detection during contrast infusion. RESULTS: Adequate LV cavity opacification with contrast was possible in 38/39 patients. The mean radionuclide EF was 50+/-16% (range 19-73). There was no statistically significant difference between the mean nuclear EF and averaged echocardiographically determined EF (51+/-18%). The mean bias was 0.6 with limits of agreement that were +15 and -14. CONCLUSION: This study demonstrated that prototype software successfully tracked the contrast enhanced endocardial border allowing accurate calculation of LV EF.

Automated mutual exclusion rules discovery for structured observational codes in echocardiography reporting.

Structured reporting in medicine has been argued to support and enhance machine-assisted processing and communication of pertinent information. Retrospective studies showed that structured echocardiography reports, constructed through point-and-click selection of finding codes (FCs), contain pair-wise contradictory FCs (e.g., "No tricuspid regurgitation" and "Severe regurgitation") downgrading report quality and reliability thereof. In a prospective study, contradictions were detected automatically using an extensive rule set that encodes mutual exclusion patterns between FCs. Rules creation is a labor and knowledge-intensive task that could benefit from automation. We propose a machine-learning approach to discover mutual exclusion rules in a corpus of 101,211 structured echocardiography reports through semantic and statistical analysis. Ground truth is derived from the extensive prospectively evaluated rule set. On the unseen test set, F-measure (0.439) and above-chance level AUC (0.885) show that our approach can potentially support the manual rules creation process. Our methods discovered previously unknown rules per expert review.