An 83-year-old woman is brought to the emergency department due to chest pressure accompanied by nausea and vomiting. She felt well until 3 days ago when she was watching television and experienced substernal chest discomfort that radiated to her back. The pain lasted nearly an hour before resolving spontaneously; she also had nausea and vomiting at that time. The patient has never had chest pain before and has had no further discomfort since. She attributes the entire experience to drinking expired milk. The patient is currently without symptoms but is seen in the emergency department at the insistence of her daughter, who is a physician. Other medical problems include overactive bladder and osteoarthritis. Medications include oxybutynin and ibuprofen as needed.
Blood pressure is 110/75 mm Hg, pulse is 61/min, and respirations are 12/min. The patient is in no acute distress. Jugular venous pulsations are normal. Lungs are clear to auscultation bilaterally. Apical impulse is normal. No heart murmurs are heard. Pulses are 2+ and symmetrical. There is no edema.
ECG shows normal sinus rhythm with 2-mm Q waves in leads II, III, and aVF. Laboratory results are as follows:
The patient is admitted to the intensive care unit and scheduled for coronary angiography. Shortly after arriving on the floor, she is noted to be markedly dyspneic. Repeat blood pressure is 90/45 mm Hg, pulse is 125/min, and respirations are 20/min. Lung examination reveals bilateral diffuse crackles. A pulmonary arterial catheter is placed, with the results shown below.
Which of the following is the most likely diagnosis in this patient?

Question

An 83-year-old woman is brought to the emergency department due to chest pressure accompanied by nausea and vomiting.  She felt well until 3 days ago when she was watching television and experienced substernal chest discomfort that radiated to her back.  The pain lasted nearly an hour before resolving spontaneously; she also had nausea and vomiting at that time.  The patient has never had chest pain before and has had no further discomfort since.  She attributes the entire experience to drinking expired milk.  The patient is currently without symptoms but is seen in the emergency department at the insistence of her daughter, who is a physician.  Other medical problems include overactive bladder and osteoarthritis.  Medications include oxybutynin and ibuprofen as needed.
Blood pressure is 110/75 mm Hg, pulse is 61/min, and respirations are 12/min.  The patient is in no acute distress.  Jugular venous pulsations are normal.  Lungs are clear to auscultation bilaterally.  Apical impulse is normal.  No heart murmurs are heard.  Pulses are 2+ and symmetrical.  There is no edema.
ECG shows normal sinus rhythm with 2-mm Q waves in leads II, III, and aVF.  Laboratory results are as follows:
 The patient is admitted to the intensive care unit and scheduled for coronary angiography.  Shortly after arriving on the floor, she is noted to be markedly dyspneic.  Repeat blood pressure is 90/45 mm Hg, pulse is 125/min, and respirations are 20/min.  Lung examination reveals bilateral diffuse crackles.  A pulmonary arterial catheter is placed, with the results shown below.
 Which of the following is the most likely diagnosis in this patient?

Quizplus · Accepted Answer

11ec193a_95c8_4472_853d_bf142813bd46_MD0002_00 A delay (eg, >24 hours) in coronary reperfusion increases risk of a mechanical complication following acute myocardial infarction (MI). This patient likely had an inferior wall MI (chest pain, nausea/vomiting, and Q waves in II, III, and avF) 3 days ago; her acute decompensation is likely due to papillary muscle rupture. Papillary muscle rupture is more common in women and typically occurs during or within 3-5 days of non-ST-elevation or ST-elevation MI. It usually involves the posteromedial papillary muscle, which is typically affected by an inferior wall MI because its blood supply is solely from the posterior descending artery (usually a branch of the right coronary artery). The anterolateral papillary muscle receives dual blood supply and is less commonly affected. Papillary muscle rupture usually causes rapid-onset pulmonary edema and cardiogenic shock due to acute mitral regurgitation. Acute left-sided heart failure results in elevated pulmonary capillary wedge pressure (PCWP) as well as elevated pulmonary arterial and right-sided heart chamber pressure. A new holosystolic murmur is often present; however, due to equalization of left atrial and left ventricular pressures, the murmur may be faint or inaudible. Bedside echocardiography confirms the diagnosis, and treatment involves emergent mitral valve repair. (Choice A) Left ventricular aneurysm is a late complication of transmural MI of the anterolateral wall. ECG typically shows Q waves with persistent ST elevation in the corresponding leads. (Choice C) Pulmonary embolism can present with acute dyspnea and hypotension, but it does not cause significant pulmonary edema. (Choice D) Pure right ventricular infarction can occur with inferior wall MI and typically results in hypotension. However, pulmonary edema is not typical, and PCWP is low or normal (rather than elevated) as left ventricular function remains intact. (Choice E) Like papillary muscle rupture, ventricular septal rupture most commonly occurs at the time of acute MI or within 3-5 days and presents with hypotension, cardiogenic shock, and a new, harsh holosystolic murmur. However, pulmonary edema may be less prominent than in papillary muscle rupture. In addition, because left-sided oxygenated blood mixes with deoxygenated blood in the right ventricle, pulmonary arterial catheter should show a "step-up" in oxygen level from the right atrium to the right ventricle. Educational objective: Papillary muscle rupture may occur acutely or within 3-5 days of acute myocardial infarction, most commonly one that affects the inferior wall. Patients have rapid-onset pulmonary edema and cardiogenic shock due to acute mitral regurgitation. A new holosystolic murmur is often, but not always, present. __________ References: Massive mitral regurgitation secondary to acute ischemic papillary muscle rupture: the role of echocardiography. (http://www.ncbi.nlm.nih.gov/pubmed/20690097)

An 83-Year-Old Woman Is Brought to the Emergency Department Due