Depressed ejection fraction, image from The POCUS Atlas

An 44 year-old male with no reported medical history (though limited access to medical care) presents with lower extremity swelling. He states that the symptoms have been gradually worsening over the past 3 months. He notes occasional fatigue while at work but denies chest pain, shortness of breath, leg pain or changes in urination.

A point-of-care ultrasound is performed showing decreased left ventricular ejection fraction. The patient was admitted for further evaluation and management of new-onset congestive heart failure.

Algorithm for the Evaluation of Lower Extremity Edema with Ultrasound

Gallery

The POCUS Atlas
The ultrasound images and videos used in this post come from The POCUS Atlas, a collaborative collection focusing on rare, exotic and perfectly captured ultrasound images.

• DVT
• Cirrhosis
• Soft Tissue

Nodular liver contour, ascites

Ascites

Cobblestoning

Cobblestoning

Longitudinal view of a ruptured Baker cyst

References

1. Trayes KP, Studdiford JS, Pickle S, Tully AS. Edema: diagnosis and management. Am Fam Physician. 2013;88(2):102-110.
2. Goyal A, Cusick AS, Bhutta BS. Peripheral Edema. [Updated 2022 Nov 19]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK554452/
3. Smith, C. Clinical manifestations and evaluation of edema in adults. Post TW, ed. UpToDate. Waltham, MA: UpToDate Inc. http://www.uptodate.com. Accessed 2/11/2023.

The post Lower Extremity Edema Ultrasound appeared first on Differential Diagnosis of.

A 48 year-old male with a history of congestive heart failure s/p left ventricular assist device is brought in by EMS with low-flow alarms. According to prehospital report, the patient had otherwise been in his usual state of health and had been shocked by his ICD multiple times prior to their arrival. No vital signs could be obtained en route.

On arrival in the emergency department, the patient was awake and responding appropriately to questions. His MAP was 80mmHg, an audible whir was auscultated from his device and the skin surrounding the percutaneous exit site appeared normal.

ECG

POCUS

The patient’s device was inactivated with a magnet to prevent further ineffectual shocks. An arterial line was placed for continuous blood pressure measurement. He was sedated and externally defibrillated with return to normal sinus rhythm prior to admission to the CCU.

An Algorithm for the Evaluation of Unstable LVAD¹

Reference

Stenberg R, Shenvi C. Targeted evaluation of patients with left ventricular assist devices and shock or hypotension. Ann Emerg Med. 2020;76(1):34-41.

The post LVAD appeared first on Differential Diagnosis of.

43F with a history of HTN and diastolic heart failure presenting with two days of shortness of breath. Reports that symptoms are worse at night when lying down to sleep and associated with a cough productive of white sputum. She also reports intermittent left-sided chest pain, described as sharp and exacerbated by cough or deep inspiration. She denies fevers/chills, nausea/vomiting, sick contacts or recent travel.
m

Physical Exam:

Labs/Studies:

• Troponin: 0.15
• Procalcitonin: 0.15
• CBC: 10.9/9.1/26.4/296
• BMP: 134/4.6/104/22/56/2.87/214

Imaging:

Pericardial Effusion

Measured in the largest dimension, suggestive of a moderate to large pericardial effusion.

E-Point Septal Separation

E-Point Septal Separation (EPSS), estimated here is the smallest distance between the anterior leaflet of the mitral valve and intraventricular septum. Values > 12mm are suggestive of depressed ejection fraction.

Left Ventricular Hypertrophy

Thickened left ventricular wall.

Pericardial Effusion - Subxiphoid

Pericardial Effusion - Parasternal Long

Pericardial Effusion - Parasternal Short

• CXR: Consolidation involving the majority of the right lung, cardiomegaly.
• Bedside Echo: LVEF 55%, concentric LVH, no wall motion abnormality, moderate pericardial effusion noted, RV not collapsed.

Assessment/Plan:

43F with a history of HTN, diastolic heart failure presenting with SOB.

#SOB: CXR finding of right-sided consolidation with history of productive cough, evidence of leukocytosis with neutrophil predominance, and relative hypoxemia suggestive of community-acquired pneumonia. No evidence of systemic inflammatory response. PE unlikely, patient is not bed-bound and alternative diagnosis more likely.
– Start empiric antimicrobial therapy ceftriaxone 1g IV q24h, azithromycin 500mg IV q24h.

#Pericardial Effusion: Noted on bedside echo, no evidence of RV collapse to suggest cardiac tamponade. Also, no JVD and pulsus paradoxus measured at 8mmHg.
– Obtain formal transthoracic echocardiogram to evaluate effusion.
– Consult cardiology if worsening hemodynamics

#Elevated Troponin: No ECG changes suggestive of acute ST-elevation MI. May represent NSTEMI though historical features not consistent with ACS.
– Trend troponin/EKG q.8.h. x3
– Give aspirin 325mg, consider anti-coagulation.
– Consider stress echo prior to discharge

#Elevated Creatinine: Baseline unknown, likely acute component with or without chronic kidney disease.
– Volume resuscitation as tolerated, follow repeat chemistry.

#Hypertension: Asymptomatic, resume home medications.

Physiology of Cardiac Tamponade ¹

• Intrapericardial pressure (IPP) normally reflects intrathoracic pressure (ITP).
• Inspiration: low ITP → low RAP → increased RA filling.
• Expiration: high ITP → low LAP → increased LA filling.
• Increased pericardial fluid → increased IPP → increased LA/RA filling pressures (diastolic dysfunction) → increased variation with respiration.
• Earliest hemodynamic change in cardiac tamponade is JVD or IVC dilation.

IVC variation as marker for RAP ¹

Grading Pericardial Effusions ¹

History and Physical Exam in Patients with Acute Pericarditis ^2,3

Differential Diagnosis of Pericardial Effusion ^2-8

References:

1. Schairer, J. R., Biswas, S., Keteyian, S. J., & Ananthasubramaniam, K. (2011). A Systematic Approach to Evaluation of Pericardial Effusion and Cardiac Tamponade. Cardiology in Review, 19(5), 233–238. doi:10.1097/CRD.0b013e31821e202c
2. Khandaker MH, Espinosa RE, Nishimura RA, et al. Pericardial Disease: Diagnosis and Management. Mayo Clinic Proceedings. 2010;85(6):572-593. doi:10.4065/mcp.2010.0046.
3. Lange, RA, Hillis, LD. Clinical practice. Acute pericarditis. The New England journal of medicine. 2004;351(21), 2195–2202. doi:10.1056/NEJMcp041997
4. Imazio M, Adler Y. Management of pericardial effusion. Eur Heart J. 2013;34(16):1186-1197. doi:10.1093/eurheartj/ehs372.
5. LeWinter MM. Clinical practice. Acute pericarditis. N Engl J Med. 2014;371(25):2410-2416. doi:10.1056/NEJMcp1404070.
6. Vakamudi S, Ho N, Cremer PC. Pericardial Effusions: Causes, Diagnosis, and Management. Prog Cardiovasc Dis. 2017;59(4):380-388. doi:10.1016/j.pcad.2016.12.009.
7. Imazio M, Mayosi BM, Brucato A, et al. Triage and management of pericardial effusion. J Cardiovasc Med (Hagerstown). 2010;11(12):928-935. doi:10.2459/JCM.0b013e32833e5788.
8. Maisch B, Seferović PM, Ristić AD, et al. Guidelines on the diagnosis and management of pericardial diseases executive summary; The Task force on the diagnosis and management of pericardial diseases of the European society of cardiology. Eur Heart J. 2004;25(7):587-610. doi:10.1016/j.ehj.2004.02.002.

The post Pericardial Effusion appeared first on Differential Diagnosis of.

• QRS in limb leads <5mm
• QRS in precordial leads <10mm

General Causes

• Fluid, fat or air attenuating signal
• Myocardial infiltration
• Loss of viable myocardium

Example

Differential Diagnosis of Low Voltage ECG

References

1. Madias JE. Low QRS voltage and its causes. J Electrocardiol. 2008;41(6):498–500. doi:10.1016/j.jelectrocard.2008.06.021.
2. WikEM: Low ECG voltage

The post Low Voltage ECG appeared first on Differential Diagnosis of.

48F with a history of Grave disease (off medications for 4 months), presenting with palpitations. Noted gradual onset of palpitations while at rest, describing a pounding sensation lasting 3-4 hours and persistent (though improved) on presentation. Symptoms not associated with chest pain, shortness of breath, loss of consciousness, nor triggered by exertion. She reported a history of 8-10 episodes in the past for which she did not seek medical attention. Review of systems notable only for heat intolerance.

On physical examination, vital signs were notable for tachycardia (HR 138bpm). No alteration in mental status, murmur, tremor or hyperreflexia appreciated.

Labs

• Hb: 14.7
• Urine hCG: negative
• TSH: <0.01
• Total T3: 311ng/dL
• Free T4: 2.64ng/dL

ECG

Sinus Tachycardia

Impression/Plan

Palpitations due to sinus tachycardia from symptomatic hyperthyroidism secondary to medication non-adherence. Improved with propranolol, discharged with methimazole and PMD follow-up.

Algorithm for the Evaluation and Management of Palpitations^{1, 2}

Evaluation of Palpitations

History and Physical

Subjective description of symptom quality

Rapid and regular beating suggests paroxysmal SVT or VT. Rapid and irregular beating suggests atrial fibrillation, atrial flutter, or variable conduction block.

Stop/start sensation: PAC or PVC

Rapid fluttering: Sustained supraventricular or ventricular tachycardia

Pounding in neck: Produced by canon A waves from AV dissociation (VT, complete heart block, SVT)

Onset and offset

Random, episodic, lasting instants: Suggests PAC or PVC

Gradual onset and offset: Sinus tachycardia

Abrupt onset and offset: SVT or VT

Syncope

Suggests hemodynamically significant arrhythmia, often VT

Examination

Identify evidence of structural, valvular heart disease

ECG¹

References

1. Zimetbaum P, Josephson ME. Evaluation of patients with palpitations. N Engl J Med. 1998;338(19):1369-1373. doi:10.1056/NEJM199805073381907.
2. Probst MA, Mower WR, Kanzaria HK, Hoffman JR, Buch EF, Sun BC. Analysis of emergency department visits for palpitations (from the National Hospital Ambulatory Medical Care Survey). The American Journal of Cardiology. 2014;113(10):1685-1690. doi:10.1016/j.amjcard.2014.02.020.
3. Abbott AV. Diagnostic approach to palpitations. Am Fam Physician. 2005;71(4):743-750.

The post Palpitations appeared first on Differential Diagnosis of.

An overhead page alerts you to an arriving patient with cardiac arrest. An approximately 35-year-old male was running away from police officers and collapsed after being shot with a stun gun. The patient was found to be pulseless, CPR was started by police officers and the patient is en route.

An Algorithm for the Evaluation and Management of Cardiac Arrest with Ultrasonography

Causes of Cardiac (and non-cardiac) Arrest

Sudden cardiac arrest (SCA) leading to sudden cardiac death (SCD) if not successfully resuscitated, refers to the unexpected collapse of circulatory function. Available epidemiologic data for in-hospital and out-of-hospital cardiac arrest (OHCA) point appropriately to cardiac processes as the most common cause, though extra-cardiac processes (most frequently respiratory), comprise up to 40% of cases^1-3.

Identifying the underlying cause is critical as several reversible precipitants require rapid identification. However, the usual diagnostic techniques may be challenging, limited or absent – including patient history, detailed examination, and diagnostic studies.

The initial rhythm detected upon evaluation is most suggestive of the etiologic precipitant. Pulseless ventricular tachycardia (pVT) or ventricular fibrillation (VF) is suggestive of a cardiac process – most commonly an acute coronary syndrome although heart failure or other structural and non-structural heart defects associated with dysrhythmias may be at fault⁴.

Pulseless electrical activity (PEA) presents a broader differential diagnosis as it essentially represents severe shock. The most common extra-cardiac cause is hypoxia – commonly secondary to pulmonary processes including small and large airway obstruction (bronchospasm, aspiration, foreign body, edema). Other causes include substance intoxication, medication adverse effect^5,6, or electrolyte disturbances⁷. Finally, any precipitant of shock may ultimately lead to PEA, including hypovolemia/hemorrhage, obstruction (massive pulmonary embolus⁸, tamponade, tension pneumothorax), and distribution (sepsis).

Asystole is the absence of even disorganized electrical discharge and is the terminal degeneration of any of the previously-mentioned rhythms if left untreated.

Management of Cardiac Arrest

Optimizing survival outcomes in patients with cardiac arrest is dependent on early resuscitation with the prioritization of interventions demonstrated to have survival benefit. When advanced notice is available, prepare the resuscitation area including airway equipment (with adjuncts to assist ventilation and waveform capnography devices). Adopt the leadership position and assign roles for chest compressions, airway support, application of monitor/defibrillator, and establishment of peripheral access.

High-quality chest compressions with minimal interruptions are the foundation of successful resuscitation – and guideline changes prioritizing compressions have demonstrated detectable improvements in rates of successful resuscitation^9,10. Measurement of quantitative end-tidal capnography can guide adequacy of chest compressions^11,12 and an abrupt increase may signal restoration of circulation without necessitating interruptions of chest compressions^13,14. Sustained, low measures of end-tidal CO2 despite appropriate resuscitation may signal futility and (alongside other factors) guides termination of resuscitation^11,12.

The next critical step in restoring circulation is prompt defibrillation of eligible rhythms (pVT/VF) when detected. The immediate delivery of 200J (uptitrated to the device maximum for subsequent shocks) of biphasic energy and restoration of a perfusing rhythm is one of few interventions with clear benefits. For pVT/VF that persists despite multiple countershocks (more than three), the addition of an intravenous antiarrhythmic appears to improve survival to hospital admission. The ARREST trial was a randomized controlled study comparing amiodarone to its diluent as placebo for OHCA with refractory pVT/VF showing significant improvement in survival to hospital admission for the amiodarone group¹⁵. This was followed by the ALIVE trial comparing amiodarone and lidocaine which showed significantly higher rates of survival to hospital admission in the amiodarone group¹⁶. However, a more recent randomized trial comparing amiodarone (in a novel diluent less likely to cause hypotension), lidocaine, and placebo in a similar patient population showed less convincing results, with no detected difference in survival or the secondary outcome of favorable neurological outcome for either amiodarone or lidocaine compared with placebo¹⁷. The heterogeneity of available data contributed to current guidelines which recommend that either amiodarone or lidocaine may be used for shock-refractory pVT/VF¹⁸.

Current guidelines also recommend the administration of vasopressors (epinephrine 1mg every 3-5 minutes). In one randomized controlled trial exploring the long-standing guideline recommendations, epinephrine was associated with increased rates of restoration of spontaneous circulation, though no significant impact on the primary outcome of survival to hospital discharge was identified¹⁹. Physiologically, increased systemic vascular resistance combined with positive beta-adrenergic impact on cardiac output would be expected to complement resuscitative efforts. However, more recent studies have suggested that arrest physiology and unanticipated pharmacologic effects may complicate this simplistic interpretation – particularly when patient-centered outcomes are emphasized. Research exploring the timing and amount of epinephrine suggest that earlier administration and higher cumulative doses are associated with negative impacts on survival to hospital discharge and favorable neurological outcomes^20-22.

Ultimately, treatment should focus on optimal execution of measures with clear benefits (namely chest compressions and early defibrillation of eligible rhythms). Other management considerations with which the emergency physician is familiar with including establishing peripheral access and definitive airway management can be delayed.

Rapid Diagnostic Measures for the Identification of Reversible Processes

Traditional diagnostic measures are generally unavailable during an ongoing cardiac arrest resuscitation. The emergency medicine physician must rely on the physical examination and point-of-care tests with the objective of identifying potentially reversible processes. Measurement of capillary blood glucose can exclude hypoglycemia as a contributor. Point-of-care chemistry and blood gas analyzers can identify important electrolyte derangements, as well as clarifying the primary impulse in acid-base disturbances.

End-tidal capnography was discussed previously for the guidance of ongoing resuscitation, but it may have diagnostic utility in patients with SCD. In one study the initial EtCO2 was noted to be significantly higher for primary pulmonary processes (with PEA/asystole as presenting rhythm) compared to primary cardiac processes (with pVT/VF as presenting rhythm)^23.

The use of point-of-care ultrasonography, particularly in PEA arrest where non-cardiac etiologies dominate, may help identify the etiology of arrest and direct therapy. Bedside ultrasonography should be directed first at assessment of cardiac function – examining the pericardial sac and gross abnormalities in chamber size. A pericardial effusion may suggest cardiac tamponade, ventricular collapse can be seen with hypovolemia, and asymmetric right-ventricular dilation points to pulmonary embolus where thrombolysis should be considered⁸. If cardiac ultrasound is unrevealing, thoracic ultrasound can identify pneumothorax^24-27.

In the absence of ultrasonographic abnormalities, attention turns to other rapidly reversible precipitants first. If opioid toxicity is a consideration, an attempt at reversal with naloxone has few adverse effects. If any detected rhythm is a polymorphic ventricular tachycardia characteristic of torsades de pointes – rapid infusion of magnesium sulfate should follow defibrillation. Other potentially reversible medications or toxins should be managed as appropriate.

Post-Resuscitation Steps

After successful restoration of circulation, the next management steps are critical to the patient’s long-term outcomes. A definitive airway should be established if not already secured (and if restoration of circulation was not associated with neurological recovery sufficient for independent airway protection). Circulatory support should continue with fluid resuscitation and vasopressors to maintain end-organ perfusion.

An immediate ECG should be performed to identify infarction, ischemia or precipitants of dysrhythmia. ST-segment elevation after return of spontaneous circulation (ROSC) warrants emergent angiography and possible intervention. However, given the prevalence of cardiac causes (of which coronary disease is most common) for patients with pVT/VF arrest, the presence of ST elevations is likely of insufficient sensitivity to identify all patients who would benefit from angiography. Several studies and meta-analyses have explored a more inclusive selection strategy for angiography (patients without obvious non-cardiac causes for arrest), all of which identified survival benefits with angiography and successful angioplasty when possible^28-30.

Finally, the induction of hypothermia (or targeted temperature management) has significant benefits in survivors of cardiac arrest and can be instituted in the emergency department. Studies first targeted a core temperature of 32-24°C, with a randomized controlled trial demonstrating higher rates of favorable neurological outcome and reduced mortality³¹. More recent studies suggest that a more liberal temperature target does not diffuse the positive effects of induced hypothermia. A randomized trial of 939 patients with OHCA comparing a targeted temperature of 33°C vs 36°C suggested that a lower temperature target did not confer higher benefit to mortality or recovery of neurological function³². The more liberal temperature target may alleviate adverse effects associated with hypothermia which include cardiovascular effects (bradycardia), electrolyte derangements (during induction and rewarming), and possible increased risk of infections³³. Targeted temperature management is achieved with external cooling measures or infusion of cooled fluids, rarely requiring more invasive measures³⁴. Aggregate review of available data in a recent meta-analysis further supports the use of targeted temperature management after cardiac arrest as standard-of-care³⁵.

References

1. Bergum D, Nordseth T, Mjølstad OC, Skogvoll E, Haugen BO. Causes of in-hospital cardiac arrest – Incidences and rate of recognition. Resuscitation. 2015;87:63-68. doi:10.1016/j.resuscitation.2014.11.007.
2. Wallmuller C, Meron G, Kurkciyan I, Schober A, Stratil P, Sterz F. Causes of in-hospital cardiac arrest and influence on outcome. Resuscitation. 2012;83(10):1206-1211. doi:10.1016/j.resuscitation.2012.05.001.
3. Vaartjes I, Hendrix A, Hertogh EM, et al. Sudden death in persons younger than 40 years of age: incidence and causes. European Journal of Cardiovascular Prevention & Rehabilitation. 2009;16(5):592-596. doi:10.1097/HJR.0b013e32832d555b.
4. Zheng ZJ, Croft JB, Giles WH, Mensah GA. Sudden cardiac death in the United States, 1989 to 1998. Circulation. 2001;104(18):2158-2163.
5. Hoes AW, Grobbee DE, Lubsen J, Man in ‘t Veld AJ, van der Does E, Hofman A. Diuretics, beta-blockers, and the risk for sudden cardiac death in hypertensive patients. Ann Intern Med. 1995;123(7):481-487.
6. Siscovick DS, Raghunathan TE, Psaty BM, et al. Diuretic therapy for hypertension and the risk of primary cardiac arrest. N Engl J Med. 1994;330(26):1852-1857. doi:10.1056/NEJM199406303302603.
7. Gettes LS. Electrolyte abnormalities underlying lethal and ventricular arrhythmias. Circulation. 1992;85(1 Suppl):I70-I76.
8. Kürkciyan I, Meron G, Sterz F, et al. Pulmonary embolism as a cause of cardiac arrest: presentation and outcome. Arch Intern Med. 2000;160(10):1529-1535.
9. Callaway CW, Soar J, Aibiki M, et al. Part 4: Advanced Life Support: 2015 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. In: Vol 132. American Heart Association, Inc.; 2015:S84-S145. doi:10.1161/CIR.0000000000000273.
10. Kudenchuk PJ, Redshaw JD, Stubbs BA, et al. Impact of changes in resuscitation practice on survival and neurological outcome after out-of-hospital cardiac arrest resulting from nonshockable arrhythmias. Circulation. 2012;125(14):1787-1794. doi:10.1161/CIRCULATIONAHA.111.064873.
11. Touma O, Davies M. The prognostic value of end tidal carbon dioxide during cardiac arrest: a systematic review. Resuscitation. 2013;84(11):1470-1479. doi:10.1016/j.resuscitation.2013.07.011.
12. Levine RL, Wayne MA, Miller CC. End-tidal carbon dioxide and outcome of out-of-hospital cardiac arrest. N Engl J Med. 1997;337(5):301-306. doi:10.1056/NEJM199707313370503.
13. Garnett AR, Ornato JP, Gonzalez ER, Johnson EB. End-tidal carbon dioxide monitoring during cardiopulmonary resuscitation. JAMA. 1987;257(4):512-515.
14. Falk JL, Rackow EC, Weil MH. End-tidal carbon dioxide concentration during cardiopulmonary resuscitation. N Engl J Med. 1988;318(10):607-611. doi:10.1056/NEJM198803103181005.
15. Kudenchuk PJ, Cobb LA, Copass MK, et al. Amiodarone for resuscitation after out-of-hospital cardiac arrest due to ventricular fibrillation. N Engl J Med. 1999;341(12):871-878. doi:10.1056/NEJM199909163411203.
16. Dorian P, Cass D, Schwartz B, Cooper R, Gelaznikas R, Barr A. Amiodarone as compared with lidocaine for shock-resistant ventricular fibrillation. N Engl J Med. 2002;346(12):884-890. doi:10.1056/NEJMoa013029.
17. Kudenchuk PJ, Brown SP, Daya M, et al. Amiodarone, Lidocaine, or Placebo in Out-of-Hospital Cardiac Arrest. N Engl J Med. 2016;374(18):1711-1722. doi:10.1056/NEJMoa1514204.
18. Neumar RW, Shuster M, Callaway CW, et al. Part 1: Executive Summary: 2015 American Heart Association Guidelines Update for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. In: Vol 132. American Heart Association, Inc.; 2015:S315-S367. doi:10.1161/CIR.0000000000000252.
19. Jacobs IG, Finn JC, Jelinek GA, Oxer HF, Thompson PL. Effect of adrenaline on survival in out-of-hospital cardiac arrest: A randomised double-blind placebo-controlled trial. Resuscitation. 2011;82(9):1138-1143. doi:10.1016/j.resuscitation.2011.06.029.
20. Hagihara A, Hasegawa M, Abe T, Nagata T, Wakata Y, Miyazaki S. Prehospital epinephrine use and survival among patients with out-of-hospital cardiac arrest. JAMA. 2012;307(11):1161-1168. doi:10.1001/jama.2012.294.
21. Dumas F, Bougouin W, Geri G, et al. Is epinephrine during cardiac arrest associated with worse outcomes in resuscitated patients? J Am Coll Cardiol. 2014;64(22):2360-2367. doi:10.1016/j.jacc.2014.09.036.
22. Andersen LW, Kurth T, Chase M, et al. Early administration of epinephrine (adrenaline) in patients with cardiac arrest with initial shockable rhythm in hospital: propensity score matched analysis. BMJ. 2016;353:i1577. doi:10.1136/bmj.i1577.
23. Grmec S, Lah K, Tusek-Bunc K. Difference in end-tidal CO2 between asphyxia cardiac arrest and ventricular fibrillation/pulseless ventricular tachycardia cardiac arrest in the prehospital setting. Crit Care. 2003;7(6):R139-R144. doi:10.1186/cc2369.
24. Rose JS, Bair AE, Mandavia D, Kinser DJ. The UHP ultrasound protocol: a novel ultrasound approach to the empiric evaluation of the undifferentiated hypotensive patient. American Journal of Emergency Medicine. 2001;19(4):299-302. doi:10.1053/ajem.2001.24481.
25. Hernandez C, Shuler K, Hannan H, Sonyika C, Likourezos A, Marshall J. C.A.U.S.E.: Cardiac arrest ultra-sound exam—A better approach to managing patients in primary non-arrhythmogenic cardiac arrest. Resuscitation. 2008;76(2):198-206. doi:10.1016/j.resuscitation.2007.06.033.
26. Chardoli M, Heidari F, Shuang-ming S, et al. Echocardiography integrated ACLS protocol versus con- ventional cardiopulmonary resuscitation in patients with pulseless electrical activity cardiac arrest. Chinese Journal of Traumatology. 2012;15(5):284-287. doi:10.3760/cma.j.issn.1008-1275.2012.05.005.
27. Zengin S, Yavuz E, Al B, et al. Benefits of cardiac sonography performed by a non-expert sonographer in patients with non-traumatic cardiopulmonary arrest. Resuscitation. 2016;102:105-109. doi:10.1016/j.resuscitation.2016.02.025.
28. Spaulding CM, Joly LM, Rosenberg A, et al. Immediate coronary angiography in survivors of out-of-hospital cardiac arrest. N Engl J Med. 1997;336(23):1629-1633. doi:10.1056/NEJM199706053362302.
29. Dumas F, Cariou A, Manzo-Silberman S, et al. Immediate Percutaneous Coronary Intervention Is Associated With Better Survival After Out-of-Hospital Cardiac Arrest: Insights From the PROCAT (Parisian Region Out of Hospital Cardiac Arrest) Registry. Circulation: Cardiovascular Interventions. 2010;3(3):200-207. doi:10.1161/CIRCINTERVENTIONS.109.913665.
30. Millin MG, Comer AC, Nable JV, et al. Patients without ST elevation after return of spontaneous circulation may benefit from emergent percutaneous intervention: A systematic review and meta-analysis. Resuscitation. 2016;108:54-60. doi:10.1016/j.resuscitation.2016.09.004.
31. Hypothermia after Cardiac Arrest Study Group. Mild therapeutic hypothermia to improve the neurologic outcome after cardiac arrest. N Engl J Med. 2002;346(8):549-556. doi:10.1056/NEJMoa012689.
32. Nielsen N, Wetterslev J, Cronberg T, et al. Targeted Temperature Management at 33°C versus 36°C after Cardiac Arrest. N Engl J Med. 2013;369(23):2197-2206. doi:10.1056/NEJMoa1310519.
33. Polderman KH, Peerdeman SM, Girbes AR. Hypophosphatemia and hypomagnesemia induced by cooling in patients with severe head injury. J Neurosurg. 2001;94(5):697-705. doi:10.3171/jns.2001.94.5.0697.
34. Polderman KH, Herold I. Therapeutic hypothermia and controlled normothermia in the intensive care unit: Practical considerations, side effects, and cooling methods*. Critical Care Medicine. 2009;37(3):1101-1120. doi:10.1097/CCM.0b013e3181962ad5.
35. Schenone AL, Cohen A, Patarroyo G, et al. Therapeutic hypothermia after cardiac arrest: A systematic review/meta-analysis exploring the impact of expanded criteria and targeted temperature. Resuscitation. 2016;108:102-110. doi:10.1016/j.resuscitation.2016.07.238.

The post Cardiac Arrest appeared first on Differential Diagnosis of.

Evaluation and Management

While the patient’s tachyarrhythmia is not yet associated with hypotension or evidence of malperfusion, preparation is key and includes continuous telemetry and vital sign monitoring, establishment of intravenous access, and application of cardioversion pads ¹.

The presence of atrial fibrillation is new and the rapid ventricular response (RVR) may be symptomatic of more serious and potentially reversible pathology. A thorough history and physical examination may elucidate a precipitant and should precede attempts at rate- or rhythm-control. RVR may be provoked by any of the processes that would otherwise induce a sinus tachycardia, including bleeding, infection, toxic/metabolic etiologies and endocrinopathies ^{2, 3}

Candidacy for Cardioversion

In hemodynamically stable patients with new-onset atrial fibrillation, candidacy for cardioversion includes:^4-6

• Stable without ischemia, hypotension or acute CHF
• Clear onset of <48 hours
• Non-severe symptoms
• Few prior episodes/treatments
• Existing anti-coagulation with warfarin and therapeutic INR (at least 3 weeks)
• Absence of high-risk features: rheumatic/valvular disease, severe left-ventricular dysfunction, prosthetic valves, or history of thromboembolism

Cardioversion may be pharmacologic (with procainamide, or amiodarone), or electrical (synchronized at 100-200J). Electrical cardioversion for acute atrial fibrillation is both more effective and results in shorter lengths-of-stay in the emergency department – though stable patients should participate in shared decision-making⁷. Another important consideration when cardioversion is pursued is the prevention of systemic embolization. While atrial fibrillation of duration less than 48-hours is rarely associated with systemic embolization, certain populations are at higher risk⁸. One retrospective study of 3143 patients with atrial fibrillation for less than 48-hours demonstrated an overall risk of 0.7% for thromboembolic events – though the rate was significantly higher in patients older than 60 years or with other comorbidities (heart failure, diabetes)⁹. The risk of embolic events should be weighed against the risk of bleeding.

Pharmacologic Management

For patients who are not candidates for cardioversion, rate-control should be pursued. Options include AV nodal blocking agents such as calcium channel blockers and beta-blockers¹⁵. The most frequently studied agents of each category are metoprolol and diltiazem. Both classes show comparable efficacy and safety profiles with trends favoring diltiazem^{16, 17}.

Algorithm for the management of atrial fibrillation with rapid ventricular response:

References

1. Atzema, C.L. and T.W. Barrett, Managing atrial fibrillation. Ann Emerg Med, 2015. 65(5): p. 532-9.
2. January, C.T., et al., 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation: Executive Summary. A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the Heart Rhythm Society, 2014. 64(21): p. 2246-2280.
3. Scheuermeyer, F.X., et al., Emergency Department Patients With Atrial Fibrillation or Flutter and an Acute Underlying Medical Illness May Not Benefit From Attempts to Control Rate or Rhythm. Ann Emerg Med, 2015. 65(5): p. 511-522 e2.
4. Stiell, I.G., et al., Association of the Ottawa Aggressive Protocol with rapid discharge of emergency department patients with recent-onset atrial fibrillation or flutter. CJEM, 2010. 12(3): p. 181-91.
5. von Besser, K. and A.M. Mills, Is discharge to home after emergency department cardioversion safe for the treatment of recent-onset atrial fibrillation? Ann Emerg Med, 2011. 58(6): p. 517-20.
6. Cohn, B.G., S.M. Keim, and D.M. Yealy, Is emergency department cardioversion of recent-onset atrial fibrillation safe and effective? J Emerg Med, 2013. 45(1): p. 117-27.
7. Bellone, A., et al., Cardioversion of acute atrial fibrillation in the emergency department: a prospective randomised trial. Emerg Med J, 2012. 29(3): p. 188-91.
8. Weigner, M.J., et al., Risk for clinical thromboembolism associated with conversion to sinus rhythm in patients with atrial fibrillation lasting less than 48 hours. Ann Intern Med, 1997. 126(8): p. 615-20.
9. Airaksinen, K.E., et al., Thromboembolic complications after cardioversion of acute atrial fibrillation: the FinCV (Finnish CardioVersion) study. J Am Coll Cardiol, 2013. 62(13): p. 1187-92.
10. Friberg, L., M. Rosenqvist, and G.Y. Lip, Evaluation of risk stratification schemes for ischaemic stroke and bleeding in 182 678 patients with atrial fibrillation: the Swedish Atrial Fibrillation cohort study. Eur Heart J, 2012. 33(12): p. 1500-10.
11. Lip, G.Y., et al., Refining clinical risk stratification for predicting stroke and thromboembolism in atrial fibrillation using a novel risk factor-based approach: the euro heart survey on atrial fibrillation. Chest, 2010. 137(2): p. 263-72.
12. Ntaios, G., et al., CHADS(2), CHA(2)S(2)DS(2)-VASc, and long-term stroke outcome in patients without atrial fibrillation. Neurology, 2013. 80(11): p. 1009-17.
13. Lip, G.Y., et al., Comparative validation of a novel risk score for predicting bleeding risk in anticoagulated patients with atrial fibrillation: the HAS-BLED (Hypertension, Abnormal Renal/Liver Function, Stroke, Bleeding History or Predisposition, Labile INR, Elderly, Drugs/Alcohol Concomitantly) score. J Am Coll Cardiol, 2011. 57(2): p. 173-80.
14. Pisters, R., et al., A novel user-friendly score (HAS-BLED) to assess 1-year risk of major bleeding in patients with atrial fibrillation: the Euro Heart Survey. Chest, 2010. 138(5): p. 1093-100.
15. Goralnick, E. and L.J. Bontempo, Atrial Fibrillation. Emerg Med Clin North Am, 2015. 33(3): p. 597-612.
16. Demircan, C., et al., Comparison of the effectiveness of intravenous diltiazem and metoprolol in the management of rapid ventricular rate in atrial fibrillation. Emerg Med J, 2005. 22(6): p. 411-4.
17. Fromm, C., et al., Diltiazem vs. Metoprolol in the Management of Atrial Fibrillation or Flutter with Rapid Ventricular Rate in the Emergency Department. J Emerg Med, 2015. 49(2): p. 175-82.
18. DiMarco, J.P., Atrial fibrillation and acute decompensated heart failure. Circ Heart Fail, 2009. 2(1): p. 72-3.

The post Atrial Fibrillation appeared first on Differential Diagnosis of.

Algorithm for the Evaluation of Regular, Wide-Complex Tachycardia

1. aVR: Is the initial deflection in aVR positive? If yes, then VT.
2. Concordance: Is there concordance (monophasic with same polarity) in all of the precordial leads? If yes, then VT.
3. AV Dissociation: Is there evidence of AV dissociation (fusion or capture beats)? If yes, then VT.
4. Bundle-branch morphology: Is the QRS morphology in V1 and V6 consistent with either LBBB or RBBB? If no, then VT.

References

1. Neimann J. Wide QRS Complex Tachycardias. Lecture. Harbor-UCLA Department of Emergency Medicine. 2014:1-19.
2. Vereckei A, Duray G, Szénási G, Altemose GT, Miller JM. New algorithm using only lead aVR for differential diagnosis of wide QRS complex tachycardia. Heart Rhythm. 2008;5(1):89-98. doi:10.1016/j.hrthm.2007.09.020.
3. Szelényi Z, Duray G, Katona G, et al. Comparison of the “real-life” diagnostic value of two recently published electrocardiogram methods for the differential diagnosis of wide QRS complex tachycardias. Acad Emerg Med. 2013;20(11):1121-1130. doi:10.1111/acem.12247.
4. Brugada P, Brugada J, Mont L, Smeets J, Andries EW. A new approach to the differential diagnosis of a regular tachycardia with a wide QRS complex. Circulation. 1991;83(5):1649-1659.
5. Lau EW, Pathamanathan RK, Ng GA, Cooper J, Skehan JD, Griffith MJ. The Bayesian approach improves the electrocardiographic diagnosis of broad complex tachycardia. Pacing Clin Electrophysiol. 2000;23(10 Pt 1):1519-1526.
6. B Garner J, M Miller J. Wide Complex Tachycardia – Ventricular Tachycardia or Not Ventricular Tachycardia, That Remains the Question. Arrhythm Electrophysiol Rev. 2013;2(1):23-29. doi:10.15420/aer.2013.2.1.23.
7. Vereckei A. Current algorithms for the diagnosis of wide QRS complex tachycardias. Curr Cardiol Rev. 2014;10(3):262-276.
8. Garmel GM. Wide Complex Tachycardias: Understanding this Complex Condition: Part 1 – Epidemiology and Electrophysiology. West J Emerg Med. 2008;9(1):28-39.
9. Garmel GM. Wide Complex Tachycardias: Understanding this Complex Condition Part 2 – Management, Miscellaneous Causes, and Pitfalls. West J Emerg Med. 2008;9(2):97-103.
10. Griffith MJ, Garratt CJ, Mounsey P, Camm AJ. Ventricular tachycardia as default diagnosis in broad complex tachycardia. The Lancet. 1994;343(8894):386-388.

The post Wide-complex Tachycardia appeared first on Differential Diagnosis of.

A young female with a history of schizophrenia presents to the emergency department reporting hallucinations. She had been diagnosed with schizophrenia one year previously and was briefly admitted to a psychiatric hospital. She discontinued her anti-psychotic (risperidone) two months ago, and over the past week she reports increasingly prominent auditory and visual hallucinations.

She denies recent illness, vomiting/diarrhea, changes in urinary habits, new medications, alcohol or illicit substance use. She also denies chest pain, palpitations or shortness of breath.

Vital signs are notable for a heart rate of 148bpm and are otherwise normal (including core temperature). Detailed physical examination is normal except for a rapid, regular heart rate. Mental status examination demonstrated normal level of alertness and orientation, linear and cogent responses and occasional response to internal stimuli during which she appeared anxious.

Initial evaluation and management included a 12-lead ECG which showed sinus tachycardia. Multiple boluses of normal saline were initiated while awaiting laboratory workup.

Presentation ECG demonstrates sinus tachycardia.

Update:

Laboratory studies were reviewed and unremarkable. Normal hemoglobin, normal chemistry panel, negative hCG, and negative toxicology screen. The patient remained persistently tachycardic with a heart rate ranging from 140-160bpm (again sinus tachycardia on 12-lead ECG). An atypical antipsychotic and anxiolytic were administered and additional studies were obtained. Serum TSH, troponin and D-dimer were normal and bedside ultrasound did not identify a pericardial effusion. The patient remained asymptomatic, reporting subjective improvement in anxiety and hallucinations. Psychiatry was consulted and the patient was placed in observation for monitoring of sinus tachycardia. Observation course was uneventful as the patient remained asymptomatic. Transthoracic echocardiography was normal. Psychiatry consultation recommended resumption of home anti-psychotic and outpatient follow-up. Tachycardia had improved but not resolved at the time of discharge (heart rate 109bpm) and the patient was instructed to follow-up with her primary care provider.

Algorithm for the Evaluation of Sinus Tachycardia

Any vital sign derangement is concerning and tachycardia may be associated with unanticipated death after discharge home¹. The presence of tachycardia suggests one of several categories of hemodynamic, autonomic, or endocrine/metabolic derangement.

Demand for increased cardiac output

A perceived demand for increased cardiac output will prompt chronotropic (and inotropic) amplification before hypotension develops. Causative etiologies include: volume depletion (from hemorrhage, gastrointestinal or renal losses), distributive processes (such as infection), obstruction (pulmonary embolus, or pericardial effusion with impending tamponade), or tissue hypoxia (anemia or lung disease).

Autonomic nervous system

Autonomic nervous system disturbances induced by stimulant, sympathomimetic or anti-cholinergic use, or withdrawal of certain agents such as ethanol or beta-blockers may be at fault.

Endocrine and other causes

Hyperthyroidism and pheochromocytoma should be considered, and as diagnoses of exclusion: anxiety, pain, or inappropriate sinus tachycardia².

Evaluation:

Core temperature

CBC

Troponin

D-dimer

Bedside cardiac ultrasound

Urine toxicology screen

Ethanol level

TSH/T4

Algorithm for the Evaluation of Narrow-Complex Tachycardia^3,4,5,6

References:

1. Sklar DP, Crandall CS, Loeliger E, Edmunds K, Paul I, Helitzer DL. Unanticipated Death After Discharge Home From the Emergency Department. Ann Emerg Med. 2007;49(6):735-745. doi:10.1016/j.annemergmed.2006.11.018.
2. Olshansky B, Sullivan RM. Inappropriate sinus tachycardia. J Am Coll Cardiol. 2013;61(8):793-801. doi:10.1016/j.jacc.2012.07.074.
3. Yusuf S, Camm AJ. Deciphering the sinus tachycardias. Clin Cardiol. 2005;28(6):267-276.
4. Katritsis DG, Josephson ME. Differential diagnosis of regular, narrow-QRS tachycardias. Heart Rhythm. 2015;12(7):1667-1676. doi:10.1016/j.hrthm.2015.03.046.
5. Bibas L, Levi M, Essebag V. Diagnosis and management of supraventricular tachycardias. CMAJ. 2016;188(17-18):E466-E473. doi:10.1503/cmaj.160079.
6. Link MS. Clinical practice. Evaluation and initial treatment of supraventricular tachycardia. N Engl J Med. 2012;367(15):1438-1448. doi:10.1056/NEJMcp1111259.

The post Sinus Tachycardia appeared first on Differential Diagnosis of.

Axis

• Anatomical dominance of right ventricle until approximately 6mo
• RAD normal
• eRAD suggests AV canal defect

T-waves

• 1st week of life: Upright
• Adolescent: Inverted
• Adult: Upright

Ventricular Hypertrophy

Examples

Normal Neonatal ECG

• 2mo old
• RAD
• Inverted T-waves (normal)
• Tall R-waves in V1-V3

Extreme Axis Deviation

• Neonate with Down syndrome
• Isoelectric in I, Negative in aVF negative in II  mean QRS vector -87°
• Extreme RAD suggestive of AV canal defect

LVH:

• Unrepaired Coarctation
• Deep S-wave in V1 (>98%)
• Tall R-wave in V6 (>98%)

RVH:

• 10 year-old boy with pulmonary Hypertension
• RAD after expected age for normal RAD
• Tall R-waves in V1 (>98%)
• Deep S-wave in V6 (>98%)

STEMI

• ALCAPA (anomalous origin of the left coronary artery from the pulmonary artery): coronary artery arises anomalously from the pulmonary artery; as pulmonary arterial pressure falls during the first 6 months of infancy, prograde flow through the left coronary artery ceases and may even reverse.
• HLHS (hypoplastic left heart syndrome): coronary arteries are perfused from a hypoplastic, narrow aorta that is susceptible to flow disruption
• Orthotopic heart transplant with allograft vasculopathy
• Kawasaki: coronary artery aneurysm with subsequent thrombosis

Benign early repolarization

• 14 year-old male
• Concave ST-segment elevation

Left Atrial Abnormality:

• 9mo female with mitral insufficiency
• Broad biphasic P-wave in V1
• Tall, notched P-wave in II

Prolonged QT interval

• 18-year-old female
• Familial long QT syndrome and a history of cardiac arrest

WPW:

• Delta wave, shortened PR interval

References

1. O’Connor M, McDaniel N, Brady WJ. The pediatric electrocardiogram. Part I: Age-related interpretation. Am J Emerg Med. 2008;26(2):221-228. doi:10.1016/j.ajem.2007.08.003.
2. Goodacre S, McLeod K. ABC of clinical electrocardiography: Paediatric electrocardiography. BMJ. 2002;324(7350):1382-1385.
3. O’Connor M, McDaniel N, Brady WJ. The pediatric electrocardiogram Part II: Dysrhythmias. Am J Emerg Med. 2008;26(3):348-358. doi:10.1016/j.ajem.2007.07.034.
4. O’Connor M, McDaniel N, Brady WJ. The pediatric electrocardiogram Part III: Congenital heart disease and other cardiac syndromes. Am J Emerg Med. 2008;26(4):497-503. doi:10.1016/j.ajem.2007.08.004.
5. Schwartz P. Guidelines for the interpretation of the neonatal electrocardiogram. Eur Heart J. 2002;23(17):1329-1344. doi:10.1053/euhj.2002.3274.

The post ECG Guide: Pediatrics appeared first on Differential Diagnosis of.