A 63-year-old man presents with sudden onset retrosternal chest pain that radiates to his jaw and left arm. He has a history of hypertension, hyperlipidemia, and diabetes, but he denies any previous episodes of what he is experiencing now. The patient’s ECG is shown below (Figure below).
Which coronary artery is most likely affected in this patient?
Right coronary. There are ST elevations in II, III, and aVF, indicating an inferior STEMI. Either the right coronary artery or the left circumflex artery supply this region of the heart. However, 80% of people are “right-dominant” and have the posterior descending artery originating off the right coronary artery to supply the inferior region of the heart. It is important to know the vascular anatomy of the heart and how to assess the likely vascular territory affected based on an ECG. This information is summarized in Table below:
ECG Findings in Myocardial Infarction:
and Figure below:
A 69-year-old woman with a history of hypertension, diabetes, and myocardial infarction comes to the hospital with worsening shortness of breath and leg swelling. She has an S3 on examination with crackles at both lung bases and 2+ pitting edema in her lower extremities. The level of brain natriuretic peptide is elevated and a chest x-ray shows vascular congestion with bilateral fluffy opacities.
Which of the following would be unlikely to contribute to the patient’s current presentation?
Digoxin. Digoxin is a cardiac glycoside that functions as an inotropic agent, working to increase the contractility of the heart and therefore the cardiac output. It does this by blocking the sodium–potassium pump, leading to an increased concentration of sodium ions within myocytes and subsequently an increase in intracellular calcium through the sodium–calcium exchanger. Increased intracellular calcium leads to an increased contractility of the heart. Digoxin may be used to reduce symptoms of heart failure and hospitalization rates; however, it does not decrease mortality. Important side effects include atrial tachycardia with AV block, vision changes (yellow vision), and gynecomastia. Other drug causes of gynecomastia may be remembered with the mnemonic “Some Drugs Create Awesome Knockers:” Spironolactone, Digoxin, Cimetidine, Alcohol, Ketoconazole.
goxin, Cimetidine, Alcohol, Ketoconazole. (A, B) Medication and dietary noncompliance are common precipitants of acute heart failure. (D) Naproxen is an NSAID, and NSAIDs as a class may also precipitate heart failure; other etiologic medications include β-blockers and calcium channel blockers. Note that β-blockers and calcium channel blockers may be beneficial in heart disease, but they may also contribute to heart failure if used in excess or in the setting of other precipitants of heart failure. (E) Renal failure leads to an increase in intravascular volume, which is delivered to a failing heart that already struggles to move blood forward.
A 58-year-old man presents to the hospital with persistent fatigue and some exertional dyspnea. He has a history of hypertension, diabetes, and atrial fibrillation. Cardioversion was attempted previously but without success. He was lost to follow-up, but reports that he takes lisinopril and metformin regularly. On examination, he is normotensive with a heart rate of 76 beats per minute with an irregularly irregular rhythm. There are no murmurs or extra heart sounds, and his lungs are clear to auscultation bilaterally.
Which of the following is the most appropriate next step in management?
Warfarin. This question is testing the reader’s understanding of appropriate prophylactic anticoagulation to prevent thromboembolic events. Decision about which agent to use should be guided by the patient CHADS2 score: 1 point for CHF, Hypertension, Age >75, and Diabetes; 2 points for previous Stroke or transient ischemic attack (TIA). For a score of 0, aspirin should be started; for a score of 1, aspirin or warfarin should be started; and for a score ≥2, warfarin should be started. This patient has hypertension and diabetes, giving him a CHADS2 score of 2, and therefore warfarin is the most appropriate therapy to reduce the patient’s risk of stroke.
(A) This patient has chronic atrial fibrillation, and repeat cardioversion may be attempted (since the patient is symptomatic) but only after sufficient anticoagulation. (B) Aspirin would only be appropriate if the patient’s CHADS2 score was 0 or 1. (D) Rate control is equivalent to rhythm control in chronic atrial fibrillation and has less side effects and is therefore preferred. Amiodarone can be used for rate control but is unpopular for two reasons: there are many side effects, and amiodarone is an anti-arrhythmic that may induce chemical cardioversion and cause embolization of a clot in the left atrium.
A 48-year-old man is hospitalized with shortness of breath and ascites. Over the past 8 years, he reports that he experienced symptoms of severe fatigue, painful joints, and a decreased interest in sex. He never saw a physician during this time due to an inability to obtain medical insurance. More recently, he developed severe dyspnea on exertion with swelling of his abdomen and legs. He has no medical history and takes no medications. His uncle died from liver disease. He drinks 10 to 12 beers weekly and has never smoked. On examination, he has scleral icterus with no lymphadenopathy. There is jugular venous distention and a laterally displaced PMI. He has bilateral wet rales on lung auscultation. There is no appreciable hepatomegaly, but there is flank dullness with a fluid wave on abdominal examination. He has 2+ pitting edema of his lower extremities bilaterally. Skin findings include diffusely darkened skin, spider angiomata on the chest, and palmar erythema. His laboratory values are shown below:
Which of the following could have prevented this patient’s current manifestations?
Regular phlebotomy. There are a constellation of findings in this patient that suggest the diagnosis of hemochromatosis: darkened skin, diabetes mellitus, advanced liver disease (elevated bilirubin and INR, low albumin, thrombocytopenia), heart failure (displaced PMI, elevated BNP), and a family history of liver disease. Hemochromatosis is an autosomal recessive disease caused by a mutation in the HFE gene leading to unregulated iron absorption and overload. It presents in males after the age of 40, but will present later in females due to blood loss during menstruation. Early symptoms include fatigue, arthritis, and a decreased libido. If the disease is not recognized early, iron deposition can affect many organs including the liver (primary organ affected), pancreas, and heart, leading to the manifestations seen in this patient (cirrhosis, diabetes, and dilated cardiomyopathy). Because there is no physiologic mechanism to excrete large amounts of iron, the treatment of this condition is phlebotomy on a regular basis.
(A) Methotrexate is a dihydrofolate reductase inhibitor used in the treatment of various cancers and autoimmune conditions. It is a disease-modifying antirheumatic drug (DMARD) that has been successful in the treatment of rheumatoid arthritis, but it would not be helpful here. (B) This patient drinks less than two drinks per day on average, which is within the category of moderate alcohol consumption. Though drinking alcohol is not recommended in the presence of liver disease, alcohol cessation would not prevent the progression of hemochromatosis. (D) Penicillamine is a copper chelator used in the treatment of Wilson disease. Iron chelators (e.g., deferoxamine) can be used in hemochromatosis only if the patient is not willing to undergo regular phlebotomy.
A 48-year-old woman presents to the Emergency Department with ascites and leg swelling. Your attending tells you that the patient has a history of idiopathic pulmonary fibrosis (IPF) and is now presenting with acute heart failure. The patient is at her baseline respiratory status; there is jugular venous distention, a 2/6 holosystolic murmur heard at the left lower sternal border that increases with inspiration, and a rightsided S4. Lung sounds are distant, with scattered wheezes but no rales. The attending asks you what caused this patient’s presentation.
Which of the following best represents the initial pathologic process that led to this patient’s heart failure?
Increased pulmonary artery pressure. The key here is recognizing that the patient is presenting with symptoms of right heart failure, not left heart failure. Although the most common cause of right heart failure is left heart failure, there are additional processes that may produce isolated right heart failure. Cor pulmonale is the term given to right heart failure that results from pulmonary hypertension associated with a primary pulmonary disease. Destructive lung processes will cause a loss of pulmonary vasculature, requiring that the same amount of blood volume be pumped through fewer arterioles. In addition, hypoxia from destruction of lung parenchyma will lead to hypoxic vasoconstriction, which is the lung’s mechanism for reducing ventilation–perfusion mismatch with regional hypoxia. Both of these mechanisms contribute to increased pressure in the pulmonary artery, known as pulmonary hypertension. This will lead to increased pressure load on the right ventricle, eventually leading to right heart failure that spares the distal left ventricle. Therefore, the best answer choice here is increased pulmonary artery pressure.
(A) Calcification of the aortic valve is known as senile aortic stenosis; if untreated, it results in left heart failure. (C) Certain infiltrative processes (sarcoidosis, amyloidosis, hemochromatosis) may cause heart failure by producing a restrictive cardiomyopathy which reduces the compliance of the ventricles. This would produce both left and right heart failure. (D) Fibrosis of the pericardium refers to constrictive pericarditis, which can occur as a consequence of any cause of pericarditis (viral, uremia, radiation, TB, etc.). With this diagnosis, look for Kussmaul sign on examination (paradoxical increase in jugular venous pressure during inspiration).
Click to expand