A 68-year-old man presents to the hospital with a 3-hour history of crushing substernal chest pain. He reports that the symptoms developed suddenly and were accompanied by sweating and nausea. The chest pain has been getting worse, is not exacerbated by deep inspiration, and does not radiate to his jaw or either arm. He endorses mild shortness of breath but denies subjective fevers, chills, headache, cough, abdominal pain, and diarrhea. He has a history of coronary artery disease, hypertension, diabetes, and gastroesophageal reflux disease (GERD). He takes aspirin, lisinopril, metformin, and omeprazole. His family history is significant for hypertension in both parents, and his father died of a heart attack at the age of 60. He has a 40 pack-year history of smoking, and denies any alcohol or illicit drug use. On examination, the patient is afebrile with a blood pressure of 150/96 mmHg, heart rate of 89 beats per minute, respiratory rate of 18 breaths per minute, and oxygen saturation of 97% on room air. He appears diaphoretic. There is an S3 on cardiac auscultation, with mildly elevated jugular venous pulsations and bibasilar rales on pulmonary examination. His dorsalis pedis and posterior tibial pulses are diminished bilaterally, with mild swelling around his ankles. His initial laboratory values and ECG (Figure below) are shown below.
Which of the following best represents the underlying pathology in this patient?
Rupture of a plaque with thrombosis leading to complete occlusion of a coronary artery. This is an extreme example of a long question that could be answered quickly if the reader first reads what the question is asking. This is a good strategy for long questions, since many students report that time management is challenging for the Medicine shelf examination. In this case, a brief survey of the question and answer choices would reveal that there is a process occurring that involves the patient’s coronary arteries, and therefore all that is necessary is finding the diagnosis (obvious from the ECG) and then picking an answer choice. Much of the long history and examination is unnecessary, which can be skipped or at least skimmed; the laboratory tests are normal with the only significant finding being elevated troponins. The ECG shows ST elevation in the inferior leads (II, III, aVF), confirming the diagnosis of ST elevation myocardial infarction (STEMI). The pathologic process occurring in a STEMI is most commonly due to rupture of an atherosclerotic plaque in the arterial wall of a coronary artery. Rupture of the plaque exposes tissue factor and other thrombogenic subendothelial components, leading to thrombosis and occlusion of the artery. (C) There is usually some degree of gradual narrowing of the artery due to the plaque, but rupture of the plaque with subsequent thrombosis is necessary to produce a STEMI. (A) The coronary artery occlusion is complete (not partial), which causes full thickness myocardial ischemia that manifests with ST elevations on ECG. (B) This answer refers to Prinzmetal angina, which is an unusual cause of myocardial ischemia that typically occurs in women with symptom onset in the evening. (E) Superficial erosion may occur but is not the most common mechanism in acute coronary syndromes (ACS).
A 62-year-old woman with a history of hypertension and hyperlipidemia presents to the hospital with diffuse muscle pain, weakness, and dark urine. She has no history of autoimmune or renal disease. Over the past month, she has had symptoms of cold intolerance, weight gain, and constipation. Her medications include hydrochlorothiazide, simvastatin, and gemfibrozil. Urine dipstick reveals 3+ blood; however, there are no red blood cells on microscopic analysis. Some of the other laboratory values are shown below:
Which of the following is the most likely cause of her presentation?
Medication effect. Muscle pain, weakness, and dark urine in the presence of an elevated creatine kinase (CK) should lead the reader to suspect rhabdomyolysis. This is further indicated by the blood on urine dipstick but no red blood cells on microscopy. Urine dipsticks bind hemoglobin and will be positive if there are red blood cells in the urine; however, myoglobin is similar in structure to hemoglobin and will also cause the dipstick to be positive in the absence of red blood cells on urine microscopy. CK is stored within muscle and therefore is increased in the setting of significant muscle cell destruction. Statins are known to cause myopathies, ranging from benign myalgia to severe rhabdomyolysis. Hypothyroidism is a risk factor for developing severe myopathies while on a statin, and the patient’s symptoms (weight gain, cold intolerance, and constipation) with an elevated TSH indicate that she has this risk factor. Another important risk factor for serious myopathies is the combination of a fibrate (e.g., gemfibrozil) and a statin. Initial treatment of rhabdomyolysis involves cessation of the offending agent (simvastatin) and correction of any fluid and electrolyte abnormalities.
(A) Hashimoto thyroiditis is the most common cause of hypothyroidism in developed countries, and may be the cause of this patient’s hypothyroidism. However, this is the risk factor for the patient developing rhabdomyolysis and not the cause. (B) Pyelonephritis is inflammation of the kidney and the urinalysis will be consistent with a urinary tract infection. This would not cause an elevation in CK. (C) Polymyositis is an autoimmune condition that can be diagnosed by the presence of anti-Jo antibodies. There is some overlap with the symptoms (muscle pain and weakness with elevated CK), but polymyositis would not present so acutely (symptoms develop more subacutely to chronically).
A 47-year-old woman presents at night to the Emergency Department with chest pain. She states that the pain started that evening and has progressively been getting worse. She is concerned that she is having a heart attack. The pain is described as a burning sensation associated with a sour taste in her mouth, and it started shortly after she ate dinner; it has occurred on previous occasions, but never as bad as it is now. Previously, she used calcium carbonate tablets that were effective for the pain. She has no history of heart disease or other medical problems, and she takes no regular medications. She does not smoke cigarettes or use cocaine. Her vitals are normal, and her physical examination is unremarkable. Initial laboratory tests and an ECG are normal.
Which of the following is the most likely cause of this patient’s chest pain?
: Gastroesophageal reflux disease. In a patient with a chief complaint of chest pain, it is important to consider life-threatening causes (e.g., myocardial infarction) as well as noncardiac causes of chest pain, which include disorders of the respiratory, GI, and musculoskeletal systems. This patient’s history of recurrent burning chest pain after meals that is associated with a sour taste in her mouth makes GERD the most likely diagnosis. Not all patients with ACS present with a classic history of retrosternal chest pain/pressure radiating to the jaw and left arm, so it is important to have a low index of suspicion for ACS in any patient (especially women and those with risk factors). Other cardiovascular causes of chest pain include any cause of angina (including Prinzmetal angina), pericarditis/myocarditis, and aortic dissection. Pulmonary causes include pneumonia, pulmonary embolism, pleuritis, and pneumothorax. Gastrointestinal causes include GERD, diffuse esophageal spasm, and peptic ulcer disease. Musculoskeletal causes include costochondritis, rib fracture, and muscle strain. Beyond these systems, psychiatric conditions (anxiety, panic disorder) and herpes zoster can both present as chest pain.
(A) Unstable angina is a type of ACS that presents without elevated cardiac enzymes and ± ECG findings of ischemia. The history itself is not suggestive of a cardiac etiology. (B) Myocarditis is an inflammatory process of the heart muscle that is commonly the result of a viral process (e.g., Coxsackie). It presents as pleuritic chest pain with elevations in cardiac enzymes; it can lead to heart failure from poor ventricular function. (C) Pulmonary embolism will cause pleuritic chest pain, especially if it causes pulmonary infarcts. Look for this in a patient with risk factors (Virchow triad: blood stasis, endothelial injury, and a hypercoagulable state) and with tachycardia and tachypnea. (E) Costochondritis is caused by inflammation of the costal cartilage that connects the ribs to the sternum. The typical history is chest pain that is reproduced with palpation.
A 28-year-old woman frantically presents to the Emergency Department in the middle of the night with chest discomfort that awoke her from sleep. She has experienced similar episodes a few times before, always at night, but never as bad as this. She reports a history of migraines but denies any other medical history, including heart disease. Her medications include NSAIDs as needed and OCPs. She smokes a half pack of cigarettes a day but denies any alcohol or drug use. She admits that she gets “stressed out” a lot but believes that overall she lives a healthy lifestyle. Laboratory values show normal CK and troponin. An ECG shows ST elevations and she is taken for coronary angiography that does not show any significant coronary occlusions.
What is the most appropriate treatment for this patient?
Diltiazem. High-dose calcium channel blockers are the preferred treatment for Prinzmetal angina. Sublingual nitroglycerin may also be prescribed to relieve chest pain during attacks and to minimize frequent visits to the Emergency Department. Smoking cessation is important and should be addressed.
This is a fairly classic presentation of Prinzmetal (variant) angina, which is caused by focal vasospasm of a coronary artery and typically occurs in young smokers that may have a history of other vasospastic disease (Raynaud, migraines, etc.). It usually occurs at night, and an ECG may show ST elevation as a result of transient myocardial ischemia that usually does not lead to infarction. During coronary angiography, vasospasm can be induced with the use of ergonovine, acetylcholine, or hyperventilation. Of note, this diagnosis can be differentiated from Takotsubo cardiomyopathy (can also present with ST elevations with normal coronary angiography) by the normal serum CK and troponin.
(A) Alprazolam is a benzodiazepine used for panic disorder. (C) Alteplase is a fibrinolytic used in acute myocardial infarction when PCI is unavailable. (D) NSAIDs may be used for viral pericarditis, but the sudden onset and recurrent description of the symptoms does not fit this diagnosis.
A 73-year-old woman is brought in by paramedics after fainting in the mall and hitting her face. She does not remember any preceding symptoms, and she did not lose control of her bowel or bladder. Witnesses at the scene say that she was down for less than a minute, then woke up and was fairly alert. She was bleeding from a laceration on her chin and paramedics were called. When she arrived at the hospital, her initial laboratory values were normal and an EEG did not show epileptiform activity. She is placed on a cardiac monitor. The following day, she becomes lightheaded and loses consciousness while lying in bed, and her monitor shows tachycardia with the QRS complexes being uniformly longer than 120 ms.
What is the most common cause of this rhythm disturbance?
Ischemic heart disease. The vignette describes an episode of ventricular tachycardia, which is indicated by the wide QRS complexes on her monitor. A serious arrhythmia should have been high on the differential given her episode of syncope with the red flag of head trauma, indicating a very sudden loss of consciousness without any ability to brace herself, which is typical of a cardiac etiology. The most common cause of ventricular tachycardia is ischemic heart disease. Patients that suffer a myocardial infarction have scarring of the myocardium that disrupts the normal electrical pathways and increases the risk of developing this dangerous rhythm. (A, C) Uncontrolled hypertension and accessory pathways are not the most common causes of ventricular tachycardia. (B) Distention of the pulmonary veins is thought to be a mechanism of atrial fibrillation.
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