Mrs. Hart is a 70-year-old woman who was admitted to the CICU two days ago for signs and symptoms consistent with cardiogenic shock. Since her admission, she has been on maximal diuretics, requiring greater doses of intravenous dobutamine. Unfortunately, her liver and renal function continue to worsen, and urine output is decreasing. A right heart catheterization reveals elevated biventricular filling pressures with a cardiac index of 1.7 L/min/m2 by the Fick method.

What is the next best step?

A

Continue current measures and monitor for improvement

B

Switch from dobutamine to norepinephrine

C

Place an intra-aortic balloon pump (IABP)

D

Resume guideline directed medical therapy

Explanation

The Correct answer is C – Place an intra-aortic balloon pump.

This patient is between the SCAI Shock Stages C and D with elevated venous pressures, decreased urine output, and worsening signs of hypoperfusion. She has been started on appropriate therapies, including diuresis and inotropic support. The relevant Class 2a recommendation is that in patients with cardiogenic shock, temporary MCS is reasonable when end-organ function cannot be maintained by pharmacologic means to support cardiac function (LOE B-NR). Thus, the next best step is a form of temporary MCS. IABP is appropriate to help increase coronary perfusion and offload the left ventricle. In fact, for patients who are not rapidly responding to initial shock measures, triage to centers that can provide temporary MCS may be considered to optimize management (Class 2b, LOE C-LD).

The guidelines further state that in patients presenting with cardiogenic shock, placement of a pulmonary arterial line may be considered to define hemodynamic subsets and appropriate management strategies (Class 2B, LOE B-NR). And so, if time allows escalation to MCS should be guided by invasively obtained hemodynamic data via PA catheterization. Several observational experiences have associated PA catheterization use with improved outcomes, particularly in conjunction with short-term MCS. Additionally, PA catheterization is useful when there is diagnostic uncertainty as to the cause of hypotension or end-organ dysfunction, particularly when the patient in shock is not responding to empiric initial measures, such as in this patient.

There are additional appropriate measures at this time that are more institution-dependent. An institutional shock team would be very helpful here as they often comprise multidisciplinary teams of heart failure and critical care specialists, interventional cardiologists, surgeons, and palliative care specialists. As such, there is a Class 2a recommendation that in patients with cardiogenic shock, management by a multidisciplinary team experienced in shock is reasonable (LOE B-NR). Most documented experiences have suggested outcomes improve after shock teams are instituted. For instance, in one such experience, using a shock team was associated with improved 30-day all-cause mortality (HR, 0.61; 95% CI, 0.41–0.93) and reduced in-hospital mortality (61.0% vs. 47.9%; P=0.041).

Choice A – Continue current measures and monitor for improvement – is incorrect. This patient has been deteriorating on current measures since admission and is at higher risk for SCAI Shock Stage E – extremis, refractory hypotension/hypoperfusion, and cardiac arrest and, therefore requires escalation of therapy

Choice B- Switch from dobutamine to norepinephrine – is incorrect. The Class 1 LOE B-NR recommendation is that in patients with cardiogenic shock, intravenous inotropic support should be used to maintain systemic perfusion and maintain end-organ performance. Dobutamine is a more potent inotropic agent than norepinephrine. Stopping dobutamine in the setting of her low cardiac index would be incorrect.

Choice D – Resume guideline-directed medical therapy – is incorrect. This patient’s shock is getting worse. The Class 1 LOE B-NR recommendation is that in patients with HFrEF, GDMT should be initiated during hospitalization after clinical stability is achieved. Restarting medications now would be premature.

Main Takeaway

In patients with cardiogenic shock, temporary MCS is reasonable when end-organ function cannot be maintained by pharmacologic means to support cardiac function.

Guideline Loc.

Section 9.5