Chest Pain
A 71-year-old male presents after a syncopal episode. He reports 12 hours of recurrent substernal chest pressure. A report from the patient's primary care physician's office states that an EKG performed four days ago was completely normal. Repeat EKG in the ED reveals no ST-segment elevation, but you do note a right bundle-branch block, and a left anterior fascicle block. Troponin I is elevated above normal at 1.6. What intervention would be indicated to provide definitive management for the findings seen on EKG in this patient? A. Urgent placement of a cardiac pacemaker B. Radiofrequency ablation C. Emergent revascularization with thrombolytics or percutaneous coronary intervention (PCI) D. Continuous cardiac monitoring for 24-48 hours
The answer is A. "In the face of an AMI, the risks of complete heart block are much greater when new or preexisting bi- or trifascicular conduction blocks are present. In this setting, prophylactic placement of a ventricular demand pacemaker is indicated."
A 14 year old presents just after smoking crack cocaine and complains of chest pain. He describes it as sharp and stabbing in the middle of his chest. His EKG is normal. The intern reads the CXR as "negative" but your supervising resident asks you to have another look (see Figure), after which you make the diagnosis of: [image] photo courtesy of eMedicine.com A. Pneumomediastinum B. Pneumonia C. Congestive heart failure D. Aortic dissection
The answer is A. Look closely along the left heart border and mediastinum. There is a thin strip of air. Pneumomediastinum and pneumopericardium result from Valsalva maneuvers, barotrauma, asthma, and cocaine inhalation from positive pressure devices. On physical exam there may be a Hamman's sign or mediastinal crunch heard over the precordium. Westermark's sign is dilation of pulmonary vessels proximal to a pulmonary embolism resulting in a cut-off appearance of the vessel on CXR.
60 year old male presents to the emergency department with chest pain. His monitor strip, shown below, reveals: [image] A. second degree AV block Mobitz Type 2 B. second degree AV block Mobitz Type 1 C. complete heart block D. first degree AV block
The answer is A. Mobitz type 2 is characterized by an unexpected, non-conducted atrial impulses. The R-R interval and P-R intervals are constant.
A 60 year old male presented to the emergency department with chest pain. He subsequently became unresponsive. The monitor shows the rhythm below. The rhythm is: [image] A. ventricular tachycardia B. atrial flutter C. atrial fibrillation with rapid ventricular response D. sinus tachycardia
The answer is A. Ventricular tachycardia is wide and complex. It is distinguished from supraventricular tachycardia by width and morphology of the QRS complexes. (Though there are numerous exceptions, supraventricular tachycardias usually exhibit narrow QRS complexes with morphology similar to that when the patient is in sinus rhythm.)
A 72-year-old male presents with five hours of substernal chest pain and pressure despite taking three sublingual nitroglycerin. You order an EKG. What findings on the EKG would indicate that this patient is potentially a candidate for thrombolytic therapy? A. Ventricular tachycardia B. ST-segment elevation of at least 1 mm in two or more contiguous leads C. ST-segment depression of at least 2mm in any precordial lead D. Atrial fibrillation with a rapid ventricular response
The answer is B. "Fibrinolytic therapy is indicated for patients with STEMI (as a reperfusion option) if time to treatment is <6 to 12 hours from symptom onset, and the ECG has at least 1-mm ST-segment elevation in two or more contiguous leads."
A 60 year old male with known coronary artery disease presents complaining of recent chest pain. The chest pain typically occurs after exertion and lasts about 15 minutes. He takes a sublingual nitroglycerin or rests and the pain subsides. He is currently pain free. He has had similar episodes for the last 6 months with no change in frequency or intensity of the chest pain. He most likely has: A. acute myocardial infarction B. stable angina C. unstable angina D. acute coronary syndrome E. variant (Prinzmetal's) angina
The answer is B. Acute coronary syndrome is a spectrum of myocardial ischemia through myocardial necrosis. The spectrum includes unstable angina, stable angina and acute myocardial infarction. Unstable angina is of new or recent onset, of changing character, or angina at rest. Stable angina or angina pectoris is chronic and episodic, usually lasting 5 to 15 minutes and relieved by rest or nitroglycerin. Variant angina usually occurs at rest, often precipitated by tobacco or cocaine use. It is defined as ST elevation that resolves as pain goes away. It is thought to be due to artery spasm.
A 65-year-old female presents 2 weeks after an MI complaining of chest pain, fever, and shortness of breath. She has a new friction rub on exam and a leukocytosis. She most likely has: A. pneumonia B. Dressler's syndrome C. congestive heart failure D. pulmonary embolism E. new myocardial infarction
The answer is B. Dressler's syndrome is fever, pleuritis, leukocytosis, pericardial friction rub, and evidence of pericarditis or pleural effusion occurring several weeks after MI. It is thought to be autoimmune in nature and is treated with NSAIDs.
A 64 year old female presents to the emergency department with chief complaints of occipital headache and chest pain. Physical examination reveals a blood pressure of 200/118 as well as edema of the optic disk. Of the diagnoses below, the most likely is: A. hypertensive urgency B. hypertensive crisis C. white-coat hypertension D. acute hypertensive (non-emergency/non-urgency) episode E. moderate hypertension
The answer is B. Elevated blood pressure in the setting of optic disk edema is a hallmark of malignant hypertension (also known as hypertensive emergency or hypertensive crisis). While hypertensive urgency is not consistently defined in the medical literature, this patient's presentation indicates that there is some end-organ damage and thus the diagnosis is malignant hypertension. The "white-coat" syndrome, in which patients' blood pressures are elevated only in the clinical setting and not at home, has been shown to account for as many as a fifth of all cases of newly diagnosed "hypertension." Understanding of this phenomenom is important for emergency physicians, since its frequency explains why patients should not be given a diagnosis of new-onset hypertension based on E.D. measurements.
A 29-year-old male presents to the emergency department complaining of substernal chest pressure. The patient used cocaine and alcohol 3 hours prior to admission. On exam, the patient has a blood pressure of 160/100 mm Hg and heart rate of 150 beats per minute with ST-segment changes in the inferior leads on EKG. Which of the following is the best medication to treat the patient's cardiovascular status? A. Lidocaine B. Lorazepam C. Metoprolol D. Phenoxybenzamine
The answer is B. In a patient with suspected myocardial ischemia secondary to cocaine abuse, beta blockade is probably contraindicated as it may lead to uncontrolled alpha-agonism and could cause worsening hypertension (this notion continues to be debated). Lidocaine is contraindicated and the use of nitroglycerin is controversial.
f the following, which diagnosis is most likely given the EKG shown in the Figure? [image] A. posterior myocardial infarction B. inferior myocardial infarction C. anteroseptal myocardial infarction D. anterior myocardial infarction
The answer is B. The EKG demonstrates classic findings (ST-segment elevations in II, III, AVF) associated with inferior myocardial infarction.
Which coronary vessel is usually the cause of the myocardial infarction in a patient with ST elevation in V1, V2, and V3? A. right coronary artery (RCA) B. left anterior descending (LAD) C. right ventricular branch of the right coronary artery D. left circumflex artery E. posterior descending branch of the right coronary artery
The answer is B. This EKG pattern is consistent with that of anterior wall myocardial infarction (MI). The LAD supplies the anterior wall of the myocardium. The left circumflex artery, the LAD, or a branch of the RCA supplies the lateral wall of the left ventricle. Proximal occlusion of the LAD will give ST elevation in leads V1-6, aVL and I (an anterolateral MI). Occlusion of a branch of the RCA will result in an inferolateral MI (ST elevation in leads II, III, aVF and I, aVL, V5 and V6). The RCA supplies the inferior wall and SA node. Occlusion in leads II, III and aVF causes an inferior MI. The right ventricle is usually supplied by the RCA or, less commonly, a dominant left circumflex. ST elevation in leads V4 and V5 of a right-side leads EKG suggests infarction of the right ventricle. A posterior MI (ST depression in V1-V3) results from occlusion of the RCA, its posterior descending branch, or a dominant left circumflex.
A 58-year-old male previously in good health presents with chest pain for two hours. Vital signs are BP 126/78, HR 80 (sinus rhythm), RR 14, oxygen saturation 99%, T 36.8. His EKG shows ST segment elevation in leads II, III, aVF and V1. ST-segment elevation is greater in lead III than in lead II. What additional diagnostic test is indicated prior to giving nitroglycerin? A. d-dimer B. Echocardiogram C. EKG with right-sided leads D. CXR
The answer is C. "Nitrate-induced hypotension is also suggestive of right ventricular infarction, and of tamponade. Initial therapy for both would include volume loading and avoidance of vasodilators or other agents that may lower the blood pressure." "ST segment elevation in lead V1 in the setting of inferior MI (i.e., ST segment elevation in leads II, III, and aVF rather than in the setting of concomitant ST segment elevation in all anterior precordial leads) is suggestive of right ventricular infarction." "ST segment elevation is usually greater in lead III than in lead II when right ventricular infarction coexists with inferior AMI." "Application of "right-sided" precordial leads is the best means to diagnose right ventricular infarction with the ECG. These leads, as a mirror image of the left precordial leads, demonstrate ST segment elevation with right ventricular infarction in leads V3R to V6R, with V4R having the highest sensitivity."
A 51-year-old male with long-standing hypertension presents with abrupt onset of severe chest pain radiating to the back. He describes a tearing sensation. Vital signs are HR 110, BP 175/105, RR 20, T 37.4. EKG shows LVH. CBC, electrolytes, BUN/Creatinine are all normal. CXR is as shown below. What diagnostic test would be most appropriate for making a definitive diagnosis at this time? [image] A. MRI of the thoracic spine B. Esophagram using Gastrograffin C. CT of the chest with IV contrast D. Aortogram
The answer is C. CXR source: http://cdemcurriculum.org/ssm/cardiovascular/images/cxr_with_widened_mediastinum.jpg http://cdemcurriculum.org "CT of the chest is the test most often used to confirm the diagnosis of aortic dissection. CT is readily available in most Emergency Departments, and has a sensitivity of 83-98% and specificity of 87-100% for aortic dissection (highest accuracy with helical scans). Other benefits associated with the use of CT include the ability to identify intramural thrombus, pericardial effusion, and potentially reveal another etiology for the patient's pain. The major disadvantage of CT is the need for iodinated contrast, which requires normal renal function."
A patient with nontraumatic chest pain is administered nitroglycerin in the field and has subsequent drop in blood pressure. An EKG reveals ST-segment elevation in lead V4R. What is the diagnosis? A. unstable angina B. anteroseptal MI C. right-ventricular MI D. pericarditis E. pulmonary embolism
The answer is C. The ST-segment elevation in the right-sided lead V4R is strongly suggestive of right-ventricular MI.
A 56 year old female presents to the emergency department complaining that she can't catch her breath. She has associated intermittent sharp chest pain on the right side of her chest that began 3 days ago after she returned from a trip to Europe. She has a history of hypertension (HTN) and is on a beta blocker and hormone replacement therapy. Her physical exam is unremarkable except for a heart rate of 110 and respiratory rate of 28. Her EKG shows sinus tachycardia. Her SpO2 is 90% on 4L nasal cannula and her chest X-ray is normal. The next test should be: A. Lower extremity doppler B. Exercise treadmill C. Chest CT scan D. Bedside echocardiogram
The answer is C. This patient most likely has a PE and has a sufficient presentation to warrant immediate anticoagulation therapy with heparin unless contraindications are present. Risk factors for PE include history of deep venous thrombosis (DVT), recent surgery or pregnancy, limb immobilization, confinement to bed, or underlying malignancy. Other risk factors include HTN, obesity, estrogen replacement therapy or oral contraceptives, autoimmune diseases, and cancer. Symptoms of PE include: dyspnea, pleuritic chest pain, apprehension, cough, hemoptysis, sweating, and syncope. The diagnosis is made: (1) if DVT is demonstrated by duplex US, venography, CT, MRI or some other technique; (2) if V/Q scan is convincingly positive; or (3) if pulmonary angiography, spiral CT, or another convincing test is positive.
A 22 year old presents with chest pain and the following EKG: [image] He reports no past medical history and no family history of medical problems. Which substance should you specifically question him about using? A. Methamphetamine B. Heroin C. Ecstasy D. Cocaine
The answer is D. Cocaine toxicity can cause a variety of cardiovascular sequelae including: cardiac dysrhythmias, coronary artery vasospasm, myocardial ischemia/infarction, and aortic dissection. The central nervous system is also commonly involved with seizures, intracranial hemorrhages/infarctions and hypertensive encephalopathy being common. Mesenteric ischemia can occur as well as rhabdomyolysis.
Of the following choices, which diagnosis is most likely in a 50-year old male with substernal chest pain and the EKG shown in the Figure? [image] A. inferior myocardial ischemia B. pulmonary embolism C. pericarditis D. right-ventricular myocardial ischemia
The answer is D. The EKG's marked ST-segment elevation in V1, in the absence of ST-segment elevation in the other anteroseptal leads (V2-V3), is suggestive of right-ventricular ischemia. Right-sided leads should be performed to further assess this possibility.
Which of the following pairs of hypertension-associated disease and specific therapy represent reasonable therapeutic approaches? A. pheochromocytoma - hydrochlorothiazide B. pregnancy induced hypertension - furosemide C. angina - phentolamine D. aortic dissection - nitroprusside/propranolol E. bilateral renal artery stenosis - captopril
The answer is D. The specific utilization of various medications for the above-mentioned disease processes is subject to debate. For example, aortic dissection therapy generally includes nitroprusside and a beta-blocker, and labetalol is considered a reasonable drug of first choice for many hypertensive conditions. However, captopril is not safe in patients with renal artery stenosis. The problem with using captopril in these patients is that its mechanism of action incurs risk of renal failure in patients with some types of chronic renal disease including renal artery stenosis. Patients with pregnancy induced hypertension have a decreased intravascular volume, despite the edema, and pheochromocytoma is treated with phentolamine.
A 70 year old woman presents with chest pain that began 2 hours ago. She describes it as substernal radiating to her jaw and left shoulder; there is no other area of pain or radiation. She took an aspirin at home but the pain is not better. She also took 3 sublingual nitroglycerin tablets en route to the hospital. Her initial EKG shows ST elevation in the anterior leads >2mm and ST depression in the inferior leads. The nurse has already administered oxygen, placed her on an EKG monitor, and attained IV access. You order beta-blockade and nitroglycerin for pain relief, and the supervising resident asks you which of the following should be done next: A. Call her primary care physician. B. Send her to radiology for a good-quality chest X-ray. C. Give her a GI cocktail to check for pain relief from this. D. Call cardiology for a decision between thrombolytic and percutaneous coronary intervention. E. Call cardiology to request a stat echocardiogram to check for wall motion abnormalities and aortic dissection.
The answer is D. This patient is having an acute myocardial infarction. AMI is defined when two of the following three findings are present: clinical history of chest pain of at least 20 minutes duration, EKG changes and/or positive myocardial enzyme testing. This patient has ST elevation with concomitant ST depression in contiguous leads with chest pain. She needs immediate thrombolytic therapy or cardiac catheterization; if percutaneous coronary intervention (PCI) can be achieved within 90-120 minutes of emergency department arrival, the literature supports its selection over thrombolytic therapy as primary intervention. In preparation for either thrombolytic therapy or PCI, you need to control her pain, maximize O2 delivery, decrease work of the heart and inhibit platelet function. O2, nitroglycerin and morphine will increase O2 delivery to the heart. A beta blocker, which should also be administered to AMI patients who lack contraindications, will decrease the work of the heart, and aspirin will inhibit platelets. A glycoprotein IIb/IIIa-inhibitor should also be administered - selections will depend on the exact treatment course chosen for the patient. Anticoagulation with low molecular weight heparin or unfractionated heparin (dose being dependent on exact treatment course for patient) should be started if there are no patient historical or chest X-ray findings suggestive of aortic dissection.
Once aortic dissection is suspected the physician should plan for early cardiothoracic surgery consultation; additionally, which of the following is the best next step? A. Start IV nitroglycerin to lower blood pressure and IV beta blocker to decrease shearing forces on the aorta. B. Start IV sodium nitroprusside to decrease shearing forces on the aorta. C. Order an MRI to characterize the dissection's anatomy. D. Start IV beta blocker to decrease shearing forces on the aorta and IV sodium nitroprusside to lower blood pressure. E. Start IV nitroglycerin to lower blood pressure and give aspirin to inhibit platelets.
The answer is D. When a patient has an aortic dissection, it is important to decrease further dissection (i.e. extension of the vascular tear) by reducing shearing forces on the aorta using negative inotropes (beta blockers) and to control hypertension. Sodium nitroprusside is often used for blood pressure control in dissections as it is an easily titratable antihypertensive. Because sodium nitroprusside increases heart rate and may increase shearing forces, a beta blocker should be started before (or concurrently with) it. The effects of nitroglycerin are not easily titratable, making it a less desirable drug for blood pressure control. Aspirin should be avoided, as it may increase bleeding complications. Morphine may be used for pain control and to decrease sympathetic tone. Imaging decisions surrounding aortic dissection are complex, incorporating such factors as patient safety (e.g. transport to imaging areas, administration of dye loads) and need for assessment of nonaortic structures (e.g. pericardial space) and functional anatomy (e.g. valvular regurgitation). As a general rule, MRI is not emergently available and lacks sufficient monitoring capabilities for a patient with suspected acute aortic dissection (MRI is useful for long-term, outpatient monitoring of dissection in most centers).
