A 57-year-old male with a history of hyperlipidemia is admitted to the intensive care unit with hypotension necessitating vasopressor support. He had been in his usual state of health, but in the preceding 24 hours, he developed progressively worsening dyspnea, culminating in respiratory failure and necessitating intubation.
His admission electrocardiogram is shown below:
His presenting troponin-T is 2.52 ng/mL (reference <0.03 ng/mL). Shortly after admission, the patient is witnessed to have repeated episodes of self-terminating ventricular tachycardia, the longest of which last up to 45 seconds.
An echocardiogram is performed and demonstrates severe biventricular dysfunction with an estimated left ventricular ejection fraction of 12%.
Which of the following would be the most appropriate next step in management?
Correct Answer: A
The patient presents with rapidly decompensating heart failure leading to cardiogenic shock. His 12-lead electrocardiogram reveals Q-waves consistent with old inferior, anteroseptal and anterior wall infarction, suggesting that ischemia may be related causally to the biventricular dysfunction. While consideration of ventricular support devices in this case is important, a univentricular support device, such as an IABP or percutaneous LVAD, would likely be inadequate in the presence of biventricular failure. Furthermore, there is minimal evidence in favor of IABP or PVAD in cardiogenic shock. His ventricular arrhythmias are likely a consequence of the acute decompensation on the background of severe biventricular cardiomyopathy.
Immediate diagnostic angiography with intent to perform revascularization is indicated in patients with non-ST elevation myocardial infarction (NSTEMI) who have refractory angina or hemodynamic or electrical instability. Acute myocardial infarction is the leading cause of cardiogenic shock and early revascularization is associated with improved mortality when compared to medical therapy. Mortality nevertheless remains high in this subset of patients. In patients for whom percutaneous coronary intervention may not be possible or for whom a mechanical complication of myocardial infarction is present, coronary artery bypass grafting can be considered.
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A 76-year-old female undergoes uncomplicated coronary angiography via the right femoral artery for evaluation of a newly diagnosed cardiomyopathy. She is found to be without obstructive coronary artery disease. The patient is admitted to the intensive care unit for further monitoring.
Her femoral angiogram is shown in the figure below:
Two days following admission, the patient begins to cough. Shortly thereafter, she is observed to have sudden and rapid expansion of her right lower quadrant, with associated hypotension.
Which of the following is the most appropriate next step?
Correct Answer: C
Routine diagnostic coronary angiography with percutaneous coronary intervention can be performed via the radial or femoral artery. The radial artery approach carries similar procedural success with lower rates of bleeding and vascular complications compared to the femoral artery. When femoral artery access is utilized, cannulation of the common femoral artery (CFA) should occur above the femoral artery bifurcation and below the internal epigastric artery. This target can be identified fluoroscopically by visualizing the femoral head, which typically lies above the CFA bifurcation and below the internal epigastric artery and permits easy compression of the common femoral artery following the procedure. In patients with a “high stick,” that is a stick arterial puncture site at or above the superior border of the femoral head, there is an increased risk of retroperitoneal bleeding. Conversely, “low sticks” at or below the inferior border of the femoral head carry an increased risk of pseudoaneurysm formation.
Access site bleeding should be suspected in postprocedural patients with hypotension, lower abdominal or back pain, or rapidly expanding hematoma. The first step in managing active hemorrhage centers on primary bleeding control with manual compression of the common femoral artery. Thereafter, anticoagulation should be reversed and blood products should be administered. Computed tomography of the abdomen can be utilized when the diagnosis is uncertain and hemodynamic parameters have stabilized. While most bleeding stops with manual pressure, surgical exploration can be considered following failure of manual compression.
An 88-year-old male with complex coronary disease that includes prior three-vessel coronary artery bypass grafting and prior complete heart block necessitating dual chamber permanent pacemaker implantation presents with substernal chest pain identical in character to his past angina.
His presenting electrocardiogram is:
His presenting troponin-T is 0.54 ng/mL (reference <0.03 ng/mL).
Which of the following is the next best step in management?
Early diagnosis of an ST elevation myocardial infarction (STEMI) remains key in determining management. Early diagnosis leads to earlier reperfusion which ultimately improves mortality. Diagnosis of STEMI necessitates the presence of new ST elevations in at least two contiguous leads (of ≥2 mm in men ≥40 years, ≥2.5 mm in men <40 years, or ≥1.5 mm in women in leads V2 -V3 and/or ≥1 mm in other contiguous chest leads or limb leads).
The diagnosis of myocardial ischemia and infarction in the presence of conduction disturbances proves more challenging. Ischemic symptoms with a presumed new left bundle branch block (LBBB) or right bundle branch block (RBBB) that is not rate related is associated with adverse prognosis. In patients with an LBBB, ST segment elevation ≥1 mm concordant with the QRS complex in any lead may be an indicator of acute myocardial ischemia. Similar criteria can be used to diagnose acute myocardial infarction in the presence of right ventricular pacing as demonstrated in this patient’s electrocardiogram. Because of the concordant QRS-ST changes apparent in the inferior leads of this patient’s electrocardiogram, angiography should be pursued.
A 67-year-old man presents with 3 days of severe substernal chest pain.
A surface echocardiogram reveals an estimated left ventricular ejection fraction of 22% with inferior and inferoseptal akinesis. A 1.5 cm ventricular septal defect at the junction of the inferior wall and septum is noted and is associated with bidirectional shunting. Coronary angiography reveals a 50% narrowing of the ostium of the left main coronary artery, subtotal occlusion of the left anterior descending artery, and total occlusion of the right coronary artery with left to right collaterals. A plan for surgical revascularization, with patch repair of the ventricular septal defect, is formulated. Shortly thereafter, the patient develops progressive cardiogenic shock with ventricular tachycardia.
Which of the following is the next BEST step in management?
Mechanical complications of myocardial infarction include rupture of the ventricular free wall, rupture of the interventricular septum, and rupture of the papillary muscle with acute mitral regurgitation; these can occur within the first 24 hours post–myocardial infarction or as late as 2 weeks. With mainstream revascularization therapies, the incidence of rupture of the interventricular septum occurs in 0.2% of myocardial infarctions. Infarction related to the left anterior descending artery appears to have the highest risk of rupture of the interventricular septum. Definitive management of a post–myocardial infarction ventricular septal rupture necessitates closure. In patients with cardiogenic shock, urgent surgical intervention is necessary. Temporary hemodynamic support can be provided by afterload reduction with vasodilators and intraaortic balloon pump counterpulsation. This minimizes the degree of left to right shunting. Veno-arterial extracorporeal membrane oxygenation (ECMO) could result in a prohibitively high increase in ventricular afterload which would worsen left to right shunting. Inotropes alone may not achieve the goal of afterload reduction.
A 58-year-old with active tobacco use, hyperlipidemia, and hypertension presents with substernal chest pain that developed following snow shoveling.
Shortly following his presentation, he is observed to have a witnessed cardiac arrest with multiple episodes of ventricular fibrillation. He required 10 minutes of cardiopulmonary resuscitation with advanced cardiac life support and four defibrillator therapies. Following return of spontaneous circulation (ROSC), the patient was noted to have the following laboratory data. His mental status is not determinable.
His post-ROSC ECG is shown:
What is the MOST appropriate timing for coronary angiography?
The timing of coronary angiography in patients with cardiac arrest and unknown mental status is controversial. Coronary angiography should be performed emergently for cardiac arrest patients with suspected cardiac etiology of arrest and ST segment elevation on ECG. Patients with ventricular fibrillation or pulseless ventricular tachycardia should be considered at high risk for coronary event, for which urgent angiography should be considered. Emergency coronary angiography is reasonable for select (eg, electrically or hemodynamically unstable) adult patients who are comatose after out-of-hospital cardiac arrest of suspected cardiac origin even without ST elevation on ECG.
There are no guideline consensus statements on the timing of angiography in the absence of ST elevations. There is additional evidence that in those patients with out-of-hospital cardiac arrest and a nonshockable rhythm, early coronary angiography (within 24 hours) was associated with improved mortality. Thus, many argue in favor of early coronary angiography.
Neurologic prognosis is difficult to reliably determine immediately following resuscitation. Thus, the decision with regard to cardiovascular intervention should be made independent of perception of neurologic prognosis.
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