A previously healthy and independently functional 77-year-old man is brought to the catheterization laboratory after developing sudden-onset chest pain radiating to the jaw and shortness of breath. ECG by EMS during transfer revealed ST elevation in V2 to V4 and leads I and aVL. The patient was in respiratory distress during transfer requiring emergent endotracheal intubation. His BP is 70/30 mmHg and heart rate is 110 per minute. Angiogram reveals fresh mural thrombus in proximal LAD, which is stented with BMS with resultant TIMI-2 flow. No significant disease is noted in the RCA and circumflex vessels. An echo reveals a left ventricular ejection fraction (LVEF) of 30% with no significant valvular pathology. He is subsequently transferred to the critical care unit (CCU) in critical condition. His current vital signs are as follows: BP 80/40 mmHg, HR 120 beats per minute, and SaO2 of 92% on 60% FiO2 . A PA catheter is placed.
What is the next step to be considered in the management of this patient?
Consideration for advanced mechanical support. Advanced mechanical support with IABP, ECMO, or TANDEM heart is indicated at this time. IABP reduces afterload, increases cardiac output, and reduces myocardial oxygen requirement by means of reduction in wall stress. The recently conducted Intra-aortic balloon counterpulsation in acute myocardial infarction complicated by cardiogenic shock (IABP SHOCK-II) trial failed to show a mortality benefit in this setting with IABP counterpulsation, as a result IABP support in the setting of shock is now downgraded to a IIa indication in the most recent ACC/AHA guidelines. Other supportive devices such as the TANDEM and Impella have been shown to provide superior hemodynamic support to IABP alone, although no clear benefits with regard to mortality have been noted. The patient described achieved satisfactory mechanical reperfusion and urgent CABG or repeat angiography is not indicated and nitroprusside would not be considered in this setting.
A 72-year-old woman is admitted to the hospital with acute STEMI. She has no other past medical history. She underwent BMS to the left circumflex artery with good subsequent flow. She is now free of chest pain and feels well. Echocardiogram revealed an estimated ejection fraction of 30%.
In addition to aspirin and clopidogrel what other medications must be considered in the patient’s discharge medication regimen?
Atorvastatin, lisinopril, carvedilol, and eplerenone. Current guidelines in post reperfusion care include medical management for optimal risk factor control and treatment of myocardial dysfunction. High-potency statins (atorvastatin or rosuvastatin) and β-blockers are indicated in the absence of contraindications in all patients with STEMI. ACEIs are indicated in all patients after MI with ejection fraction <40% or anterior wall MI and aldosterone antagonists are indicated in patients with MI and ejection fraction <40% with clinical signs of heart failure.
The patient had a brief (10 seconds) episode of nonsustained ventricular tachycardia (VT) at a rate of 180 beats per minute on the day of admission in the catheterization laboratory that spontaneously converted to sinus rhythm.
What additional therapy is warranted for this patient?
None of the above. This patient had a brief episode of nonsustained VT in the setting of MI. Routine antiarrhythmic therapy with amiodarone or lidocaine is not indicated in patients with MI and brief, self-limited, and hemodynamically insignificant arrhythmias within 48 hours of symptoms. This patient has low ejection fraction and warrants consideration for a primary prophylaxis ICD based largely on the Multicenter Automatic Defibrillator Implantation Trial (MADIT II) trial if ventricular function does not recover. Early use of ICD post MI was not associated with benefit in the Defibrillator in Acute Myocardial Infarction Trial (DINAMIT) and Immediate Risk Stratification Improves Survival (IRIS) trials. Patients with MI and low ejection fraction need to be reevaluated after 40 days on optimal medical therapy to determine candidacy for device therapy.
A 45-year-old man presents to an emergency room with 30 minutes of crushing chest pain. The nearest catheterization laboratory is 45 minutes away and a decision to transfer for primary PCI is made.
What is the optimal door in door out that has been associated with decreased mortality?
Within 30 minutes. Door in door out time in the setting of STEMI is the time from patient presentation to discharge from a non-PCI hospital to a PCI-capable hospital. A door in door out time of less than 30 minutes is associated with decrease in mortality.
A 46-year-old man develops sudden chest pain and collapses to the ground. Bystander Cardio-Pulmonary Resuscitation (CPR) is immediately initiated. On EMS arrival 8 minutes later, he is noted to be in ventricular fibrillation and is promptly defibrillated. His ECG shows ST elevation in the inferior leads. The patient is comatose and is intubated for airway protection.
Apart from performance of primary PCI which of the following actions is associated with mortality benefit?
Initiation of hypothermia protocol. Initiation of therapeutic hypothermia in post cardiac arrest patient has been shown to be associated with a significant mortality benefit. The patient is not in shock and administration of normal saline may lead to pulmonary edema. Prophylactic intravenous lidocaine in this setting has not been shown to have any clinical benefit and may lead to harm. The patient does not have polymorphic VT and there is no role for transvenous pacing in ischemically triggered polymorphic VT. While ECMO has been shown to be useful in patients with refractory cardiogenic shock, it is not indicated in a hemodynamically stable patient post cardiac arrest.