Electrocardiographic Diagnosis of Acute Coronary Occlusion Myocardial Infarction in Ventricular Paced Rhythm Using the Modified Sgarbossa Criteria.

STUDY OBJECTIVE: Ventricular paced rhythm is thought to obscure the electrocardiographic diagnosis of acute coronary occlusion myocardial infarction. Our primary aim was to compare the sensitivity of the modified Sgarbossa criteria (MSC) to that of the original Sgarbossa criteria for the diagnosis of occlusion myocardial infarction in patients with ventricular paced rhythm. METHODS: In this retrospective case-control investigation, we studied adult patients with ventricular paced rhythm and symptoms of acute coronary syndrome who presented in an emergency manner to 16 international cardiac referral centers between January 2008 and January 2018. The occlusion myocardial infarction group was defined angiographically as thrombolysis in myocardial infarction grade 0 to 1 flow or angiographic evidence of coronary thrombosis and peak cardiac troponin I ≥10.0 ng/mL or troponin T ≥1.0 ng/mL. There were 2 control groups: the "non-occlusion myocardial infarction-angio" group consisted of patients who underwent coronary angiography for presumed type I myocardial infarction but did not meet the definition of occlusion myocardial infarction; the "no occlusion myocardial infarction" control group consisted of randomly selected emergency department patients without occlusion myocardial infarction. RESULTS: There were 59 occlusion myocardial infarction, 90 non-occlusion myocardial infarction-angio, and 102 no occlusion myocardial infarction subjects (mean age, 72.0 years; 168 [66.9%] men). For the diagnosis of occlusion myocardial infarction, the MSC were more sensitive than the original Sgarbossa criteria (sensitivity 81% [95% confidence interval [CI] 69 to 90] versus 56% [95% CI 42 to 69]). Adding concordant ST-depression in V4 to V6 to the MSC yielded 86% (95% CI 75 to 94) sensitivity. For the no occlusion myocardial infarction control group of ED patients, additional test characteristics of MSC and original Sgarbossa criteria, respectively, were as follows: specificity 96% (95% CI 90 to 99) versus 97% (95% CI 92 to 99); negative likelihood ratio (LR) 0.19 (95% CI 0.11 to 0.33) versus 0.45 (95% CI 0.34 to 0.65); and positive LR 21 (95% CI 7.9 to 55) versus 19 (95% CI 6.1 to 59). For the non-occlusion myocardial infarction-angio control group, additional test characteristics of MSC and original Sgarbossa criteria, respectively, were as follows: specificity 84% (95% CI 76 to 91) versus 90% (95% CI 82 to 95); negative LR 0.22 (95% CI 0.13 to 0.38) versus 0.49 (95% CI 0.35 to 0.66); and positive LR 5.2 (95% CI 3.2 to 8.6) versus 5.6 (95% CI 2.9 to 11). CONCLUSION: For the diagnosis of occlusion myocardial infarction in the presence of ventricular paced rhythm, the MSC were more sensitive than the original Sgarbossa criteria; specificity was high for both rules. The MSC may contribute to clinical decisionmaking for patients with ventricular paced rhythm.

A deep neural network for 12-lead electrocardiogram interpretation outperforms a conventional algorithm, and its physician overread, in the diagnosis of atrial fibrillation.

BACKGROUND: Automated electrocardiogram (ECG) interpretations may be erroneous, and lead to erroneous overreads, including for atrial fibrillation (AF). We compared the accuracy of the first version of a new deep neural network 12-Lead ECG algorithm (Cardiologs®) to the conventional Veritas algorithm in interpretation of AF. METHODS: 24,123 consecutive 12-lead ECGs recorded over 6 months were interpreted by 1) the Veritas® algorithm, 2) physicians who overread Veritas® (Veritas®â€¯+ physician), and 3) Cardiologs® algorithm. We randomly selected 500 out of 858 ECGs with a diagnosis of AF according to either algorithm, then compared the algorithms' interpretations, and Veritas®â€¯+ physician, with expert interpretation. To assess sensitivity for AF, we analyzed a separate database of 1473 randomly selected ECGs interpreted by both algorithms and by blinded experts. RESULTS: Among the 500 ECGs selected, 399 had a final classification of AF; 101 (20.2%) had ≥1 false positive automated interpretation. Accuracy of Cardiologs® (91.2%; CI: 82.4-94.4) was higher than Veritas® (80.2%; CI: 76.5-83.5) (p < 0.0001), and equal to Veritas®â€¯+ physician (90.0%, CI:87.1-92.3) (p = 0.12). When Veritas® was incorrect, accuracy of Veritas®â€¯+ physician was only 62% (CI 52-71); among those ECGs, Cardiologs® accuracy was 90% (CI: 82-94; p < 0.0001). The second database had 39 AF cases; sensitivity was 92% vs. 87% (p = 0.46) and specificity was 99.5% vs. 98.7% (p = 0.03) for Cardiologs® and Veritas® respectively. CONCLUSION: Cardiologs® 12-lead ECG algorithm improves the interpretation of atrial fibrillation.

Hemorrhagic Pericardial Cyst Diagnosis Accelerated by Emergency Physician Echocardiography: A Case Report.

BACKGROUND: The differential diagnosis for chest pain in the emergency department is broad and includes both benign and life-threatening conditions-with pericardial cyst as a rare example. Emergency physician-performed point-of-care focused cardiac ultrasound (FOCUS) is increasingly recognized as a useful modality in the evaluation of patients with chest pain. CASE REPORT: We report a case of hemorrhagic pericardial cyst in a young woman presenting with chest pain in which findings on FOCUS contradicted findings on chest x-ray study and thus, accelerated diagnosis and definitive treatment. We also comment on epidemiology, pathophysiology, clinical presentation, diagnosis, and management of this uncommon, potentially fatal cause of chest pain. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: This case report aims to bring an uncommon case to the attention of emergency providers and emphasize the importance of facility with FOCUS. Although definitive diagnosis and management were not accomplished at the bedside in this case, an abnormal finding on FOCUS prompted further investigation and timely treatment.

Low-Pressure Pericardial Tamponade: Case Report and Review of the Literature.

BACKGROUND: Focused cardiac ultrasound (FoCUS) is accurate for determining the presence of a pericardial effusion. Using FoCUS to evaluate for pericardial tamponade, however, is more involved. Many experts teach that tamponade is unlikely if the inferior vena cava (IVC) shows respiratory variation and is not distended. CASE REPORT: A 53-year-old woman presented to the emergency department (ED) with severe orthostatic hypotension, exertional dyspnea, and hypoxia. The evaluation did not reveal an acute cardiopulmonary etiology, but FoCUS demonstrated a pericardial effusion, with several signs consistent with tamponade. The IVC, however, was not distended. She was believed to be hypovolemic, but fluid therapy provided minimal benefit. The patient's condition improved only after aspiration of the effusion. The patient's presentation was likely a "low-pressure" pericardial tamponade. Patients with this subset of tamponade often do not have significant venous congestion, but urgent pericardial aspiration is still indicated. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Pericardial tamponade may not manifest with IVC plethora on ultrasound. Patients with low-pressure tamponade do not present with the most florid signs of tamponade, but they nonetheless fulfill diagnostic criteria for tamponade. If a non-plethoric IVC is used to rule out tamponade, the clinician risks delaying comprehensive echocardiography or other tests. Furthermore, the potential for deterioration to frank shock could be discounted, with inappropriate disposition and monitoring.

T-wave inversions on ECG as primary manifestation of Hashimoto's disease.

A middle-aged Hispanic woman presented to the emergency department (ED) reporting of acute new onset pressure-like chest pain developed at rest. It was radiated to the right arm and associated with malaise. Initial ECG demonstrated T-wave inversions (TWIs) in all anterior and lateral leads. Electrolytes, serial cardiac troponin and D-dimer were all normal. Comprehensive transthoracic echocardiogram and nuclear stress test did not reveal a cardiac cause of her symptoms.Serum thyroid-stimulating hormone was markedly elevated (207 mIU/L) and free thyroxine was low (FT4 0.07 ng/dL), consistent with severe primary hypothyroidism. Thyroperoxidase (TPO) antibodies were positive. Therapy with levothyroxine was started. No other cause of the TWIs was identified. A repeat ECG obtained 8 weeks later showed partial resolution of the TWIs. Our observations indicate that Hashimoto's disease is the most likely primary cause of this patient's extensive and profound TWI, which improved after thyroid replacement therapy.

"Persistent Juvenile" T-Wave Pattern May Not Be Persistent: Case Series and Literature Review.

BACKGROUND: T-wave inversions (TWI) can signify serious pathology, but may also represent a benign variant. One such variant has been termed the "persistent juvenile" T-wave pattern (PJTWP). It is characterized by TWI in the right precordium, and has been understood to represent an arrested stage of the normal electrocardiographic evolution from childhood. CASE REPORT: A series of four African-American (AA) women, ages 20 to 43 years, presented to the Emergency Department, and were found to have right precordial TWI that was absent on prior electrocardiograms. The diagnostic evaluation did not reveal acute cardiopulmonary causes for these new TWIs. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: The "persistent" juvenile pattern may not be actually persistent in the individual patient. In an appropriate patient, such as a young AA woman, where acute cardiopulmonary disease has been reasonably ruled out, the finding of new right precordial TWI should not preclude the diagnosis of PJTWP.

McConnell's Sign Is Not Specific for Pulmonary Embolism: Case Report and Review of the Literature.

BACKGROUND: McConnell's sign (right ventricular [RV] free wall hypokinesis with apical sparing on echocardiography) is often described as very specific for the diagnosis of pulmonary embolism (PE). We present the case of a patient who, despite manifesting a classic McConnell's sign, was not found to have a PE. CASE REPORT: A 58-year-old woman presented to the emergency department with a cough, dyspnea, and leg swelling. A bedside focused cardiac ultrasound revealed hypokinesis of the RV free wall, with apical sparing, in the apical four-chamber view. A computed tomography angiogram for PE was negative. Ultrasounds of both lower extremities were negative for deep venous thrombosis, and a D-dimer was only marginally elevated. The patient was ultimately diagnosed with pulmonary hypertension due to chronic obstructive pulmonary disease and systemic lupus erythematosus. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Emergency physicians should be aware that McConnell's sign is not completely specific for acute right heart strain from PE.