Modeling Diagnostic Expertise in Cases of Irreducible Uncertainty: The Decision-Aligned Response Model
PURPOSE/OBJECTIVE:Assessing expertise using psychometric models usually yields a measure of ability that is difficult to generalize to the complexity of diagnoses in clinical practice. However, using an item response modeling framework, it is possible to create a decision-aligned response model that captures a clinician's decision-making behavior on a continuous scale that fully represents competing diagnostic possibilities. In this proof-of-concept study, the authors demonstrate the necessary statistical conceptualization of this model using a specific electrocardiogram (ECG) example. METHOD/METHODS:The authors collected a range of ECGs with elevated ST segments due to either ST-elevation myocardial infarction (STEMI) or pericarditis. Based on pilot data, 20 ECGs were chosen to represent a continuum from "definitely STEMI" to "definitely pericarditis," including intermediate cases in which the diagnosis was intentionally unclear. Emergency medicine and cardiology physicians rated these ECGs on a 5-point scale ("definitely STEMI" to "definitely pericarditis"). The authors analyzed these ratings using a graded response model showing the degree to which each participant could separate the ECGs along the diagnostic continuum. The authors compared these metrics with the discharge diagnoses noted on chart review. RESULTS:Thirty-seven participants rated the ECGs. As desired, the ECGs represented a range of phenotypes, including cases where participants were uncertain in their diagnosis. The response model showed that participants varied both in their propensity to diagnose one condition over another and in where they placed the thresholds between the 5 diagnostic categories. The most capable participants were able to meaningfully use all categories, with precise thresholds between categories. CONCLUSIONS:The authors present a decision-aligned response model that demonstrates the confusability of a particular ECG and the skill with which a clinician can distinguish 2 diagnoses along a continuum of confusability. These results have broad implications for testing and for learning to manage uncertainty in diagnosis.
Native mitral valve staphylococcus endocarditis with a very unusual complication: Ruptured posterior mitral valve leaflet aneurysm [Case Report]
Infective endocarditis (IE) is a life-threatening disease associated with in-hospital mortality of nearly one in five cases. IE can destroy valvular tissue, which may rarely progress to aneurysm formation, most commonly at the anterior leaflet in instances of mitral valve involvement. We present a remarkable case of a patient with IE and a rare complication of a ruptured aneurysm of the posterior leaflet of the mitral valve. Two- and Three-dimensional transesophageal echocardiography, intra-operative videography, and histopathologic analysis revealed disruption at this unusual location-at the junction of the P2 and P3 scallops, surrounded by an annular abscess.
Importance Ranking of Electrocardiogram Rhythms: A Primer for Curriculum Development
INTRODUCTION/BACKGROUND:Electrocardiogram interpretation is an essential skill for emergency and critical care nurses and physicians. There remains a gap in standardized curricula and evaluation strategies used to achieve and assess competence in electrocardiogram interpretation. The purpose of this study was to develop an importance ranking of the 120 American Heart Association electrocardiogram diagnostic labels with interdisciplinary perspectives to inform curriculum development. METHODS:Data for this mixed methods study were collected through focus groups and individual semi-structured interviews. A card sort was used to assign relative importance scores to all 120 American Heart Association electrocardiogram diagnostic labels. Thematic analysis was used for qualitative data on participants' rationale for the rankings. RESULTS:The 18 participants included 6 emergency and critical care registered nurses, 5 cardiologists, and 7 emergency medicine physicians. The 5 diagnoses chosen as the most important by all disciplines were ventricular tachycardia, ventricular fibrillation, atrial fibrillation, complete heart block, and normal electrocardiogram. The "top 20" diagnoses by each discipline were also reported. Qualitative thematic content analysis revealed that participants from all 3 disciplines identified skill in electrocardiogram interpretation as clinically imperative and acknowledged the importance of recognizing normal, life threatening, and time-sensitive electrocardiogram rhythms. Additional qualitative themes, identified by individual disciplines, were reported. DISCUSSION/CONCLUSIONS:This mixed-methods approach provided valuable interdisciplinary perspectives concerning electrocardiogram curriculum case selection and prioritization. Study findings can provide a foundation for emergency and critical care educators to create local ECG educational programs. Further work is recommended to validate the list amongst a larger population of emergency and critical care frontline nurses and physicians.
Distinctive Hypertrophic Cardiomyopathy Anatomy and Obstructive Physiology in Patients Admitted With Takotsubo Syndrome
Clinical spectrum of hypertrophic cardiomyopathy (HC) has been expanded to include patients with mild or no thickening of the left ventricle (LV), who nevertheless have outflow tract obstruction at rest or after exercise, due to systolic anterior motion (SAM) and ventricular septal contact, with mitral valve elongation and papillary muscles anomalies. Apical ballooning mimicking a takotsubo syndrome (TS) wall motion pattern can occur in HC with mild septal thickening when latent obstruction becomes unrelenting. To define the prevalence of anatomic abnormalities characteristic of HC in patients diagnosed with TS, we analyzed echocardiograms of 44 unselected TS patients, age 67Â±12 years, 95% women including studies performed before the event (nâ€¯=â€¯11, median 515 days) and after recovery of left ventricular function (nâ€¯=â€¯33, median 92 days, interquartile rangeâ€¯=â€¯29 to 327) and compared the findings to 60 age and sexed matched controls. Analysis of echocardiograms was blinded to event timing, and patient vs. control status. During the ballooning event, 13 patients (30%) had SAM including 9 with LV outflow obstruction, peak gradients 71Â±40 mmHg, as well as: ventricular septal thickening (16 Â± 4 mm), elongated anterior leaflets (30 Â± 3mm), and increased mitral coaptation to posterior wall distance (17 Â± 5 mm), consistent with diagnosis of the HC phenotype. Compared to 31 TS patients without SAM, study patients with SAM had longer anterior leaflets (30 Â± 3 vs 26 Â± 4 mm, pâ€¯=â€¯0.006), thicker septum (16 Â± 4 vs 12 Â± 3 mm), increased coaptation to posterior wall distance (17 Â± 5 vs 14 Â± 4 mm, p < 0.04) and reduced distance from coaptation to septum (19 Â± 5 vs 27 Â± 5, p < 0.001). In the 13 patients with SAM, morphologic characteristics of HC persisted after normalization of LV function. In conclusion, a subset of patients experiencing TS events demonstrates a constellation of morphologic abnormalities characteristic of HC that persist after recovery of LV wall motion. These findings suggest that dynamic outflow obstruction may cause apical ballooning in susceptible patients.
A NOVEL SUBSET OF HYPERTROPHIC CARDIOMYOPATHY PATIENTS CHARACTERIZED BY ASSOCIATION WITH TAKOTSUBO-LIKE LV BALLOONING AND HOSPITAL ADMISSION [Meeting Abstract]
Background Recently the clinical spectrum of hypertrophic cardiomyopathy (HCM) has been expanded to include patients with mild or no thickening of the left ventricle (LV) yet who have outflow tract obstruction at rest or after exercise, principally due to characteristic HCM anterior mitral leaflet (AML) elongation and papillary muscle anomalies. Apical ballooning mimicking a takotsubo syndrome (TTS) wall motion pattern can occur in mild-septal-thickening HCM when latent obstruction becomes unrelenting. The objective of this study is to define the prevalence of anatomic abnormalities characteristic of HCM in an unselected population of patients diagnosed clinically with TTS. Methods We analyzed echocardiograms of 44 admitted TTS patients including studies performed during admission, before the event (n=11, median 515 days before) and after recovery of left ventricular function (n=33, median 92 days, IQR=29-327) and compared them to 60 controls, age-matched normal women. Analysis of 148 echocardiograms was blinded to timing, and patient vs. control status. Results Age was 67+/-12 years, 42 female (95%). During the ballooning event, 13 (30%) had SAM and 9 patients (20%) had LV outflow tract obstruction (LVOTO), gradients 71+/-40 mmHg. Compared to TTS patients without SAM, those with SAM had longer AML (30 vs. 26mm), and thicker septum (16 vs. 12 mm) and less distance from septum to coaptation (19 vs. 27mm), all p <=0.006. Eleven of the SAM patients had >=2 anatomic abnormalities predisposing to obstruction (defined as > 2 SD above normal), and/or an anomalous papillary muscle/chordae. In the 44 TTS patients each parameter differed from controls before, during and after the TTS event. Eight (18%) had abnormal right ventricular wall motion, none of whom were obstructed. Conclusion Thirty percent of unselected TTS patients have SAM and 20% have significant LVOT gradients. This subset had AML abnormalities and septal thickening typical of obstructive HCM and known to predispose to LVOT obstruction. They are phenotypically identical to patients with documented HCM with mild septal thickening and LVOT obstruction, who have experienced episodes of ballooning.
ENHANCING CARDIOLOGY FELLOWS' PROCEDURAL INFORMED CONSENT DISCUSSIONS USING A FORMATIVE OBSERVED STRUCTURED CLINICAL EXAMINATION [Meeting Abstract]
Background: To foster patient engagement and trust, cardiovascular procedural informed consent (IC) discussions must go beyond the routine of risks vs benefits and incorporate shared decision making (SDM). Most trainees report learning the IC process through peer observation with little emphasis on skills that enable SDM. Experiential learning with immediate faculty feedback may make it more likely that fellows incorporate these critical advanced skills into their IC practice. Method(s): We developed 3 observed structured clinical examination (OSCE) cases designed to highlight all aspects of the IC discussion for invasive cardiac procedures. We adapted validated standardized patient checklists and created a faculty observation and feedback tool. After the program, fellows completed a survey assessing the likelihood they would incorporate SDM skills into their practice. Result(s): 28 cardiology fellows successfully completed the IC OSCE. Figure 1 demonstrates that while the majority of fellows reported already routinely discussing risks and alternatives a minority reported using patient engagement skills. The majority reported they are very likely to incorporate these assessments into practice. Conclusion(s): Cardiology fellows participating in this formative IC OSCE identified SDM skills they intend to incorporate into their IC discussion practice. The clinical impact of teaching high level learners important patient engagement skills via this approach should be further studied. [Figure presented]2019 American College of Cardiology Foundation. All rights reserved
Hypertrophic cardiomyopathy with dynamic obstruction and high left ventricular outflow gradients associated with paradoxical apical ballooning
BACKGROUND:Acute left ventricular (LV) apical ballooning with normal coronary angiography occurs rarely in obstructive hypertrophic cardiomyopathy (OHCM); it may be associated with severe hemodynamic instability. METHODS, RESULTS/UNASSIGNED:We searched for acute LV ballooning with apical hypokinesia/akinesia in databases of two HCM treatment programs. Diagnosis of OHCM was made by conventional criteria of LV hypertrophy in the absence of a clinical cause for hypertrophy and mitral-septal contact. Among 1519 patients, we observed acute LV ballooning in 13 (0.9%), associated with dynamic left ventricular outflow tract (LVOT) obstruction and high gradients, 92Â Â±Â 37Â mmÂ Hg, 10 female (77%), age 64Â Â±Â 7Â years, LVEF 31.6Â Â±Â 10%. Septal hypertrophy was mild compared to that of the rest of our HCM cohort, 15 vs 20Â mm (PÂ <Â 0.00001). An elongated anterior mitral leaflet or anteriorly displaced papillary muscles occurred in 77%. Course was complicated by cardiogenic shock and heart failure in 5, and refractory heart failure in 1. High-dose beta-blockade was the mainstay of therapy. Three patients required urgent surgical relief of LVOT obstruction, 2 for refractory cardiogenic shock, and one for refractory heart failure. In the three patients, surgery immediately normalized refractory severe LV dysfunction, and immediately reversed cardiogenic shock and heart failure. All have normal LV systolic function at 45-month follow-up, and all have survived. CONCLUSIONS:Acute LV apical ballooning, associated with high dynamic LVOT gradients, may punctuate the course of obstructive HCM. The syndrome is important to recognize on echocardiography because it may be associated with profound reversible LV decompensation.
Aortic root thrombus complicated by left main coronary artery occlusion visualized by 3D echocardiography in a patient with continuous-flow left ventricular assist device [Case Report]
Aortic root thrombus is an uncommon complication of continuous-flow left ventricular assist devices (LVAD). We present the case of a 71-year-old man with ischemic cardiomyopathy who underwent destination therapy HeartMate II LVAD placement. Eighteen months later, he presented with a cerebrovascular accident followed by myocardial infarction. Transesophageal echocardiography revealed an aortic root thrombus spanning the left and noncoronary cusps and obliterating the left main coronary artery. We discuss the incidence, risk factors, and management of aortic root thrombus in LVAD patients. To our knowledge, this is the first report of three-dimensional echocardiography used to characterize an LVAD-associated aortic root thrombus.
The cardiovascular in-training examination: development, implementation, results, and future directions
BACKGROUND: The American College of Cardiology (ACC), in collaboration with the National Board of Medical Examiners (NBME), developed the first standardized in-training examination (ITE) for cardiovascular disease fellows-in-training (FITs). In addition to testing knowledge, this examination uses the newly developed ACC Curricular Milestones to provide specific, competency-based feedback to program directors and FITs. The ACC ITE has been administered more than 5,000 times since 2011. OBJECTIVES: This analysis sought to report the initial experience with the ITE, including feasibility and reliability of test development and implementation, as well as the ability of this process to provide useful feedback in key content areas. METHODS: The annual ACC ITE has been available to cardiovascular disease fellowship programs in the United States since 2011. Questions for this Web-based, secure, multiple-choice examination were developed by a group of cardiovascular disease specialists and each question was analyzed by the NBME to ensure quality. Scores were equated and standardized to allow for comparability. Trainees and program directors were provided detailed feedback, including a list of the curricular competencies tested by those questions answered incorrectly. RESULTS: The ITE was administered 5,118 times. In 2013, the examination was taken by 1,969 fellows, representing 194 training programs. Among the 3 training years, there was consistency in the examination scores. Total test scores and scores within each of the content areas increased with each FIT year (there was a statistically significant difference in each cohort's average scale score across administration years). There was also significant improvement in examination scores across the fellowship years. CONCLUSIONS: The ACC ITE is a powerful tool available to all training programs to assess medical knowledge. This examination also delivers robust and timely feedback addressing individual knowledge gaps, and thus, may serve as a basis for improving training curricula.
Giant Cell Myocarditis: Not Always a Presentation of Cardiogenic Shock
Giant cell myocarditis is a rare and often fatal disease. The most obvious presentation often described in the literature is one of rapid hemodynamic deterioration due to cardiogenic shock necessitating urgent consideration of mechanical circulatory support and heart transplantation. We present the case of a 60-year-old man whose initial presentation was consistent with myopericarditis but who went on to develop a rapid decline in left ventricular systolic function without overt hemodynamic compromise or dramatic symptomatology. Giant cell myocarditis was confirmed via endomyocardial biopsy. Combined immunosuppression with corticosteroids and calcineurin inhibitor resulted in resolution of symptoms and sustained recovery of left ventricular function one year later. Our case highlights that giant cell myocarditis does not always present with cardiogenic shock and should be considered in the evaluation of new onset cardiomyopathy of uncertain etiology as a timely diagnosis has distinct clinical implications on management and prognosis.