Three days after undergoing cardiac catheterization and coronary angioplasty for acute myocardial infarction, a 70-year-old man develops shortness of breath at rest. He has hypertension, hyperlipidemia, and type 2 diabetes mellitus. His current medications include aspirin, clopidogrel, atorvastatin, sublingual nitroglycerin, metoprolol, and insulin. He appears diaphoretic. His temperature is 37°C (98.6°F), pulse is 120/min, respirations are 22/min, and blood pressure is 100/55 mm Hg. Crackles are heard at both lung bases. Cardiac examination shows a new grade 3/6 holosystolic murmur heard best at the cardiac apex. An ECG shows sinus rhythm with T wave inversion in leads II, III, and aVF. Which of the following is the most likely explanation for this patient's symptoms?
Q42
A 54-year-old man is brought to the emergency department 1 hour after the sudden onset of shortness of breath, epigastric pain, and sweating. He has no history of similar symptoms. He has hypertension and type 2 diabetes mellitus. Current medications include amlodipine and metformin. He has smoked one pack of cigarettes daily for 20 years. He appears weak and pale. His pulse is 56/min, respirations are 18/min, and blood pressure is 100/70 mm Hg. Cardiac examination shows normal heart sounds. The lungs are clear to auscultation. The skin is cold to the touch. An ECG is shown. Bedside transthoracic echocardiography shows normal left ventricular function. High-dose aspirin is administered. Administration of which of the following is most appropriate next step in management?
Q43
A 50-year-old man presents to his primary care physician with a chief complaint of chest pain that is squeezing in nature. He used to have similar symptoms in the past while playing tennis with his friends. Yesterday, while moving furniture in his new home, he experienced this pain that lasted for 20 minutes and radiated towards his jaw and shoulder. He has been diagnosed with diabetes mellitus and hypertension for over 10 years and regularly takes his medications. The pain is not associated with nausea, vomiting, food intake, sweating, or cough. On physical examination, the patient is not in acute distress. His blood pressure is 135/85 mm Hg, heart rate is 80/min, respiratory rate is 16/min, temperature is 36.9°C (98.5°F), and BMI is 30 kg/m2. On physical examination, bilateral vesicular breath sounds are heard with absent chest tenderness. Cardiovascular examination reveals normal S1 and S2 without any abnormal sounds or murmur. Abdominal examination is within normal limit. What is the most likely cause of this patient’s condition?
Q44
Seventy-two hours after admission for an acute myocardial infarction, a 48-year-old man develops dyspnea and a productive cough with frothy sputum. Physical examination shows coarse crackles in both lungs and a blowing, holosystolic murmur heard best at the apex. ECG shows Q waves in the anteroseptal leads. Pulmonary capillary wedge pressure is 23 mm Hg. Which of the following is the most likely cause of this patient’s current condition?
Q45
A 57-year-old man presents to the emergency department because of pain in the center of his chest that is radiating down his left arm and up the left side of his neck. The pain started suddenly 30 minutes ago while the patient was at work. The patient describes the pain as squeezing in nature, 10/10 in intensity, and is associated with nausea and difficulty breathing. He has had type 2 diabetes mellitus for 15 years, hypertension for 10 years, and dyslipidemia, but he denies any history of a cardiac problem. He has a 40-pack-year history of smoking but does not drink alcohol. Vital signs include: blood pressure 80/40 mm Hg, regular pulse 90/min, and temperature 37.2°C (98.9°F). Chest auscultation reveals diffuse bilateral rales with no murmurs. ECG reveals convex ST-segment elevation in leads V1 to V6 and echocardiogram shows anterolateral hypokinesis, retrograde blood flow into the left atrium, and an ejection fraction of 45%. Which of the following best describe the mechanism of this patient’s illness?
Q46
A 48-year-old man presents early in the morning to the emergency department with a burning sensation in his chest. He describes a crushing feeling below the sternum and reports some neck pain on the left side. Furthermore, he complains of difficulty breathing. Late last night, he had come home and had eaten a family size lasagna by himself while watching TV. His past medical history is significant for type 2 diabetes and poorly controlled hypertension. The patient admits he often neglects to take his medications and has not been following his advised diet. His current medications are aspirin, metformin, and captopril. Examination reveals a distressed, overweight male sweating profusely. Which of the following is most likely to be found on auscultation?
ACS US Medical PG Practice Questions and MCQs
Question 41: Three days after undergoing cardiac catheterization and coronary angioplasty for acute myocardial infarction, a 70-year-old man develops shortness of breath at rest. He has hypertension, hyperlipidemia, and type 2 diabetes mellitus. His current medications include aspirin, clopidogrel, atorvastatin, sublingual nitroglycerin, metoprolol, and insulin. He appears diaphoretic. His temperature is 37°C (98.6°F), pulse is 120/min, respirations are 22/min, and blood pressure is 100/55 mm Hg. Crackles are heard at both lung bases. Cardiac examination shows a new grade 3/6 holosystolic murmur heard best at the cardiac apex. An ECG shows sinus rhythm with T wave inversion in leads II, III, and aVF. Which of the following is the most likely explanation for this patient's symptoms?
A. Coronary artery dissection
B. Papillary muscle rupture (Correct Answer)
C. Postmyocardial infarction syndrome
D. Early infarct-associated pericarditis
E. Ventricular septal rupture
Explanation: ***Papillary muscle rupture***
- The sudden onset of **shortness of breath** and a **new holosystolic murmur** at the apex, occurring days after an **inferior myocardial infarction** (suggested by T wave inversion in leads II, III, aVF), points strongly to acute severe **mitral regurgitation** due to papillary muscle rupture.
- This complication typically leads to **acute heart failure** (crackles, diaphoresis, hypotension, tachycardia) due to the sudden increase in left atrial pressure and volume overload.
*Coronary artery dissection*
- This complication typically occurs **during or immediately after** the cardiac catheterization procedure, presenting with acute chest pain and signs of myocardial ischemia.
- While it can cause MI, it usually wouldn't explain a *delayed* onset of heart failure symptoms with a *new murmur* days later; rather, it would manifest as worsening ischemia or a new MI.
*Postmyocardial infarction syndrome*
- Also known as **Dressler's syndrome**, this is a **late complication** (weeks to months post-MI) characterized by **pericarditis**, pleuritis, and fever.
- It does not typically present with a new, severe holosystolic murmur or acute, severe pulmonary edema as seen in this patient.
*Early infarct-associated pericarditis*
- This typically presents within **1-3 days post-MI** with pleuritic chest pain and a pericardial friction rub, but usually **without a holosystolic murmur** or significant hemodynamic collapse unless evolving into tamponade.
- This patient's symptoms are more indicative of significant valvular pathology acutely affecting cardiac output.
*Ventricular septal rupture*
- This would also present with a **new holosystolic murmur**, but it would be heard best at the **left sternal border** with a thrill, potentially accompanied by a biventricular failure.
- While crackles and hypotension are consistent, the murmur's location at the apex makes papillary muscle rupture (mitral regurgitation) more likely.
Question 42: A 54-year-old man is brought to the emergency department 1 hour after the sudden onset of shortness of breath, epigastric pain, and sweating. He has no history of similar symptoms. He has hypertension and type 2 diabetes mellitus. Current medications include amlodipine and metformin. He has smoked one pack of cigarettes daily for 20 years. He appears weak and pale. His pulse is 56/min, respirations are 18/min, and blood pressure is 100/70 mm Hg. Cardiac examination shows normal heart sounds. The lungs are clear to auscultation. The skin is cold to the touch. An ECG is shown. Bedside transthoracic echocardiography shows normal left ventricular function. High-dose aspirin is administered. Administration of which of the following is most appropriate next step in management?
A. Intravenous atropine
B. Intravenous morphine
C. Normal saline bolus (Correct Answer)
D. Phenylephrine infusion
E. Sublingual nitroglycerin
Explanation: ***Normal saline bolus***
- This patient presents with symptoms concerning for an inferior wall myocardial infarction (MI) which commonly affects the **right ventricle (RV)**. The ECG shows **ST elevation in leads II, III, and aVF**, confirming an inferior STEMI. Given his **hypotension (100/70 mm Hg)** and **bradycardia (56/min)**, he is likely experiencing RV involvement and is preload-dependent.
- A **normal saline bolus** is crucial to increase preload and improve cardiac output, especially in RV infarcts where reduced preload significantly impairs RV function and, consequently, left ventricular filling.
*Intravenous atropine*
- While the patient has bradycardia, it is secondary to the inferior MI affecting the **right coronary artery**, which often supplies the **AV node**.
- Atropine is used for symptomatic bradycardia but a fluid bolus should be prioritized in RV MI with hypotension to restore preload before considering pharmacologic interventions for heart rate.
*Intravenous morphine*
- Morphine is used for pain relief in acute MI but can cause **vasodilation**, which would worsen this patient's **hypotension**.
- In cases of RV infarction, where preload dependence is critical, morphine should be used with extreme caution or avoided due to its potential to further reduce blood pressure.
*Phenylephrine infusion*
- Phenylephrine is a **pure alpha-agonist** that causes **vasoconstriction** and increases systemic vascular resistance, thereby increasing afterload.
- Increasing afterload in the setting of an acute MI, especially one with potential RV involvement and preload dependence, can severely compromise cardiac function and worsen the patient's condition.
*Sublingual nitroglycerin*
- Nitroglycerin causes **vasodilation**, reducing both preload and afterload.
- In a patient with an **inferior wall MI** and **hypotension**, nitroglycerin is contraindicated as it can profoundly reduce preload, leading to a significant drop in blood pressure and worsening shock, especially if the right ventricle is involved.
Question 43: A 50-year-old man presents to his primary care physician with a chief complaint of chest pain that is squeezing in nature. He used to have similar symptoms in the past while playing tennis with his friends. Yesterday, while moving furniture in his new home, he experienced this pain that lasted for 20 minutes and radiated towards his jaw and shoulder. He has been diagnosed with diabetes mellitus and hypertension for over 10 years and regularly takes his medications. The pain is not associated with nausea, vomiting, food intake, sweating, or cough. On physical examination, the patient is not in acute distress. His blood pressure is 135/85 mm Hg, heart rate is 80/min, respiratory rate is 16/min, temperature is 36.9°C (98.5°F), and BMI is 30 kg/m2. On physical examination, bilateral vesicular breath sounds are heard with absent chest tenderness. Cardiovascular examination reveals normal S1 and S2 without any abnormal sounds or murmur. Abdominal examination is within normal limit. What is the most likely cause of this patient’s condition?
A. Musculoskeletal pain
B. GERD
C. Rib fracture
D. Myocardial ischemia (Correct Answer)
E. Anxiety
Explanation: ***Myocardial ischemia***
- The patient's **squeezing chest pain** that **radiates to the jaw and shoulder**, is **exertional**, and lasts for **20 minutes with associated strenuous activity** (moving furniture) strongly suggests myocardial ischemia. The presence of risk factors like **diabetes mellitus** and **hypertension** further supports this diagnosis.
- The history of similar symptoms during past activities (playing tennis) indicates a pattern of **stable angina** that has now progressed or re-occurred with an increased intensity/duration, raising suspicion for **unstable angina** or **non-ST elevation myocardial infarction (NSTEMI)**.
*Musculoskeletal pain*
- While musculoskeletal pain can cause chest discomfort, it is typically **sharp or localized**, often **reproduced with palpation**, and less likely to have the classic **squeezing, radiating pattern** seen here.
- The patient's presentation with pain lasting **20 minutes** after exertion, rather than being acute or positional, makes musculoskeletal causes less likely.
*GERD*
- **Gastroesophageal reflux disease (GERD)** can cause **burning chest pain**, often worse after meals or while lying down, and may be relieved by antacids.
- The described **squeezing pain, radiation to the jaw and shoulder**, and clear **exertional trigger** are not typical features of GERD. The absence of association with food or cough also points away from GERD.
*Rib fracture*
- A rib fracture would cause **localized, sharp pain** that is significantly **worsened by deep breathing, coughing**, or **direct palpation** over the fracture site.
- The patient's physical examination revealed **absent chest tenderness** and was not reproducible with palpation, making a rib fracture unlikely.
*Anxiety*
- **Anxiety-related chest pain** (panic attack) often presents with shortness of breath, palpitations, and tingling sensations, and is typically described as **sharp or stabbing** rather than squeezing.
- While anxiety can exacerbate symptoms, the clear **exertional trigger**, **radiating pain**, and significant **cardiovascular risk factors** make a primary diagnosis of myocardial ischemia more probable.
Question 44: Seventy-two hours after admission for an acute myocardial infarction, a 48-year-old man develops dyspnea and a productive cough with frothy sputum. Physical examination shows coarse crackles in both lungs and a blowing, holosystolic murmur heard best at the apex. ECG shows Q waves in the anteroseptal leads. Pulmonary capillary wedge pressure is 23 mm Hg. Which of the following is the most likely cause of this patient’s current condition?
A. Rupture of the ventricular free wall
B. Postmyocardial infarction syndrome
C. Aortic root dilation
D. Rupture of the interventricular septum
E. Rupture of the chordae tendineae (Correct Answer)
Explanation: ***Rupture of the chordae tendineae***
- The combination of acute dyspnea, frothy sputum (**pulmonary edema**), a new **holosystolic murmur** loudest at the apex, suggestive of **mitral regurgitation**, and high **pulmonary capillary wedge pressure** (PCWP > 18 mmHg indicating pulmonary edema) is classic for papillary muscle or chordae tendineae rupture following an **acute myocardial infarction (MI)**.
- Antero-septal Q waves suggest an infarction in an area supplied by the **left anterior descending artery**, which can also affect the **anterolateral papillary muscle** of the mitral valve.
*Rupture of the ventricular free wall*
- This typically presents as **cardiac tamponade** with hypotension, jugular venous distension, and muffled heart sounds, often leading to rapid hemodynamic collapse and death.
- While it can occur post-MI, a new holosystolic murmur and prominent pulmonary edema are not characteristic features.
*Postmyocardial infarction syndrome*
- Also known as **Dressler syndrome**, this is a **pericarditis** that develops weeks to months after an MI.
- It presents with fever, pleuritic chest pain, and pericardial friction rub and would not typically cause acute pulmonary edema or a new holosystolic murmur within 72 hours.
*Aortic root dilation*
- This condition is not directly linked to an acute MI and typically causes **aortic regurgitation**, which manifests as a **diastolic murmur** (decrescendo early diastolic murmur), not a holosystolic murmur.
- While it can cause heart failure, the acute onset post-MI with a new apical holosystolic murmur points away from this diagnosis.
*Rupture of the interventricular septum*
- This would also present with a new **holosystolic murmur**, but it would be loudest at the **left sternal border** due to a **ventricular septal defect**.
- While it can cause pulmonary edema and elevated PCWP, the murmur's location at the apex strongly points towards mitral valve pathology rather than a septal defect.
Question 45: A 57-year-old man presents to the emergency department because of pain in the center of his chest that is radiating down his left arm and up the left side of his neck. The pain started suddenly 30 minutes ago while the patient was at work. The patient describes the pain as squeezing in nature, 10/10 in intensity, and is associated with nausea and difficulty breathing. He has had type 2 diabetes mellitus for 15 years, hypertension for 10 years, and dyslipidemia, but he denies any history of a cardiac problem. He has a 40-pack-year history of smoking but does not drink alcohol. Vital signs include: blood pressure 80/40 mm Hg, regular pulse 90/min, and temperature 37.2°C (98.9°F). Chest auscultation reveals diffuse bilateral rales with no murmurs. ECG reveals convex ST-segment elevation in leads V1 to V6 and echocardiogram shows anterolateral hypokinesis, retrograde blood flow into the left atrium, and an ejection fraction of 45%. Which of the following best describe the mechanism of this patient’s illness?
A. Ventricular free wall rupture
B. Mitral leaflet thickening and fibrosis
C. Occlusion of the left anterior descending artery with interventricular septal rupture
D. Occlusion of the left anterior descending artery with rupture of a papillary muscle (Correct Answer)
E. Occlusion of the right coronary artery, with infarction of the conduction system
Explanation: ***Occlusion of the left anterior descending artery with rupture of a papillary muscle***
- The patient presents with symptoms of an **ST-elevation myocardial infarction (STEMI)** (chest pain, ST-segment elevation in V1-V6, anterolateral hypokinesis), complicated by **acute mitral regurgitation** (retrograde flow into the left atrium, diffuse rales, hypotension). This clinical picture is highly suggestive of **papillary muscle rupture**, which can occur as a mechanical complication of an MI.
- The **left anterior descending (LAD) artery** supplies the anterolateral wall of the left ventricle and often supplies one of the **papillary muscles** (usually the anterolateral papillary muscle, which has a dual blood supply, but still can be affected). Occlusion of the LAD (leading to extensive anterior and lateral wall infarction, as indicated by ECG leads V1-V6) can compromise the blood supply to a papillary muscle, leading to its dysfunction or rupture and subsequent severe mitral regurgitation.
*Ventricular free wall rupture*
- This complication typically presents with **acute cardiac tamponade**, evidenced by muffled heart sounds, jugular venous distension, and pulsus paradoxus, which are not described.
- While it causes profound hypotension, the characteristic echocardiographic finding would be **pericardial effusion**, not retrograde flow into the left atrium.
*Mitral leaflet thickening and fibrosis*
- This describes **chronic mitral stenosis** or **regurgitation** due to rheumatic heart disease or degenerative changes, which develops slowly over time.
- It does not explain the sudden onset of symptoms, acute myocardial infarction, or the specific ECG and echocardiographic findings observed in this patient.
*Occlusion of the left anterior descending artery with interventricular septal rupture*
- An **interventricular septal rupture** would present with a **new harsh systolic murmur** (often palpable thrill) at the left sternal border and evidence of left-to-right shunting, which is not mentioned in the patient's presentation.
- While it can also lead to heart failure and hypotension post-MI, the echocardiogram specifically noted **retrograde flow into the left atrium**, indicative of mitral regurgitation, not ventricular shunting.
*Occlusion of the right coronary artery, with infarction of the conduction system*
- Occlusion of the **right coronary artery (RCA)** typically causes inferior and/or posterior wall MIs, with ST-segment elevation in leads II, III, and aVF. The patient's ECG shows ST elevation in V1-V6, indicating an anterior/anterolateral MI, usually supplied by the LAD.
- While RCA occlusion can affect the **AV node** and cause bradyarrhythmias, it doesn't explain the described severe mitral regurgitation or the anterolateral hypokinesis.
Question 46: A 48-year-old man presents early in the morning to the emergency department with a burning sensation in his chest. He describes a crushing feeling below the sternum and reports some neck pain on the left side. Furthermore, he complains of difficulty breathing. Late last night, he had come home and had eaten a family size lasagna by himself while watching TV. His past medical history is significant for type 2 diabetes and poorly controlled hypertension. The patient admits he often neglects to take his medications and has not been following his advised diet. His current medications are aspirin, metformin, and captopril. Examination reveals a distressed, overweight male sweating profusely. Which of the following is most likely to be found on auscultation?
A. Expiratory wheezes
B. Ejection systolic murmur
C. Diminished breath sounds
D. Fixed splitting of the second heart sound
E. Fourth heart sound (Correct Answer)
Explanation: **Fourth heart sound**
- The patient's symptoms (chest pain, dyspnea, sweating) and risk factors (diabetes, hypertension, obesity, non-compliance) are highly suggestive of an **acute myocardial infarction (AMI)**.
- A **fourth heart sound (S4)**, also known as an atrial gallop, is commonly heard in conditions causing **left ventricular hypertrophy** or **reduced ventricular compliance**, such as uncontrolled hypertension or ischemia due to AMI.
*Expiratory wheezes*
- **Expiratory wheezes** are typically indicative of **bronchoconstriction** or airway obstruction, as seen in asthma or COPD.
- While the patient has dyspnea, there is no direct evidence to suggest an acute pulmonary issue like asthma exacerbation or COPD, and the primary presentation points towards a cardiac event.
*Ejection systolic murmur*
- An **ejection systolic murmur** is typically associated with conditions like **aortic stenosis** or **hypertrophic cardiomyopathy**.
- While these conditions can cause chest pain, the patient's acute presentation with crushing chest pain, dyspnea, and sweating, along with risk factors, is more consistent with AMI rather than a chronic valvular or hypertrophic lesion as the primary finding.
*Diminished breath sounds*
- **Diminished breath sounds** can be a sign of various pulmonary issues, such as **pneumothorax**, **pleural effusion**, or severe **emphysema**.
- While congestive heart failure secondary to an MI could eventually lead to effusions and diminished sounds, it is not the most immediate or characteristic auscultatory finding for an acute cardiac event.
*Fixed splitting of the second heart sound*
- **Fixed splitting of the second heart sound (S2)** is a classic finding in an **atrial septal defect (ASD)**.
- There is no clinical information in the patient's history or presentation to suggest a congenital heart defect.
