What to Do If an LVAD Patient Codes

When a patient with a left ventricular assist device loses signs of adequate perfusion, the standard cardiac arrest playbook does not fully apply. These patients often have no detectable pulse even when the device is working properly, which makes the usual “check for a pulse” step misleading. The American Heart Association has issued a scientific statement specifically addressing cardiopulmonary resuscitation in patients on mechanical circulatory support, reflecting how different the approach needs to be. Getting it right starts with understanding what the LVAD is doing, quickly figuring out whether the device itself has failed, and contacting the patient’s VAD coordinator team as early as possible.

Why Standard Assessment Falls Short

Most modern LVADs are continuous-flow devices, meaning they push blood in a steady stream rather than in the pulsatile beat-by-beat fashion of a healthy heart. This dramatically reduces or eliminates the arterial pulse pressure that clinicians normally rely on to confirm circulation.¹ A patient whose LVAD is running perfectly can still have no palpable radial or carotid pulse. Reaching for a wrist and feeling nothing does not, by itself, mean the patient is in cardiac arrest.

This creates an immediate problem in any emergency setting: you cannot use the absence of a pulse as your trigger to start chest compressions the way you would in a standard code. Instead, the initial assessment shifts to other markers. The AHA recommends checking skin color and capillary refill to gauge whether tissue is being perfused, and then listening over the device for an audible hum.² That hum tells you the pump is spinning. If you hear it, the device is mechanically operational, even if the patient looks critically ill. If you hear nothing, the device may be off or malfunctioning, and the situation is more urgent.

The Decision to Start Chest Compressions

Whether to perform chest compressions on an LVAD patient has been one of the most debated questions in this space. The concern is straightforward: the pump is surgically connected to the heart, and vigorous compressions could theoretically dislodge the inflow or outflow cannula, causing catastrophic internal bleeding. For years, many VAD programs discouraged compressions altogether.

The current guidance, shaped by the AHA’s scientific statement on resuscitation in patients with mechanical circulatory support, takes a more nuanced position. If the LVAD is not running (no hum, no power), the patient essentially has end-stage heart failure with no mechanical support, and standard CPR including chest compressions is appropriate.³ The AHA has specifically addressed expert consensus recommendations for the role of external chest compressions in these patients.⁴ If the device is running but the patient is unresponsive with signs of poor perfusion, the picture is murkier, and the decision depends on whether you can identify a reversible cause quickly.

The practical reality is that in a true cardiac arrest with no device function, withholding compressions is likely to be fatal. The risk of cannula dislodgement is real but needs to be weighed against certain death without intervention. Research examining the safety of chest compressions in LVAD patients has been published, though the evidence base remains limited given how uncommon these events are in any single center.⁵

Defibrillation and Ventricular Arrhythmias

Ventricular arrhythmias are common in LVAD patients and represent one of the leading reasons these patients code. Here is where things get counterintuitive: a patient with a functioning continuous-flow LVAD can sometimes tolerate ventricular tachycardia or even ventricular fibrillation for a period because the pump does not rely on coordinated cardiac contractions to move blood. The pump pulls blood from the left ventricle and pushes it into the aorta continuously, so even if the heart’s electrical system is chaotic, some forward flow continues.

That said, tolerating an arrhythmia and doing well with one are different things. Sustained ventricular arrhythmias impair right ventricular function, which the LVAD does not support. Over minutes, this leads to decreased filling of the left ventricle, reduced LVAD output, and hemodynamic collapse. Defibrillation should proceed as in any other patient when a shockable rhythm is identified on the monitor. The LVAD does not need to be disconnected or turned off before delivering a shock, and the device is designed to withstand external defibrillation.

For patients who survive the acute event, recurrent ventricular arrhythmias are a significant ongoing problem. Many LVAD patients have implantable cardioverter-defibrillators (ICDs) that deliver automatic shocks, but when arrhythmias become incessant or recur in clusters (sometimes called electrical storm), additional strategies are needed. Catheter ablation is considered in cases of incessant ventricular tachycardia, electrical storm, recurrent ICD shocks, or progressive right ventricular failure caused by the arrhythmias. The decision involves a multidisciplinary team including heart failure specialists, electrophysiologists, and the LVAD coordinator.⁶

Figuring Out Why the Patient Coded

Identifying the underlying cause is arguably more important in an LVAD arrest than in a typical code, because the list of likely culprits is different and some are rapidly reversible. Emergency clinicians evaluating these patients should be prepared for several specific scenarios: stroke, gastrointestinal bleeding, pump failure or thrombosis, right ventricular failure, and driveline infections.⁷

Pump thrombosis deserves special attention because it can present suddenly and is lethal if missed. A clot forms inside the pump or along the cannulae, increasing resistance and reducing flow. The device alarms often signal high power consumption before the patient becomes overtly symptomatic, which is why checking the device controller display and alarms is a critical early step. If the pump is still spinning but flow parameters look wrong, thrombosis is high on the differential.

Right heart failure is another common precipitant, and the numbers are striking. Depending on how it is defined, somewhere between 5% and 44% of LVAD patients develop right heart failure, which carries substantially worse outcomes.⁸ The LVAD supports only the left side of the heart. When the right ventricle fails, it cannot deliver enough blood to the left ventricle for the pump to push forward, and the patient crashes despite a functioning device. Volume status, pulmonary pressures, and right ventricular function all factor into this scenario.

Gastrointestinal bleeding is disproportionately common in LVAD patients compared to the general population, partly because continuous-flow devices can cause acquired von Willebrand syndrome, a bleeding disorder that develops after implantation. A patient who arrives hypotensive and pale with a functioning LVAD may be bleeding internally rather than experiencing a primary cardiac event. Checking hemoglobin and looking for signs of GI hemorrhage should happen early.

Monitoring Blood Pressure When There Is No Pulse

Taking a blood pressure in an LVAD patient is not as simple as inflating a cuff. Standard automated blood pressure monitors rely on detecting oscillations caused by pulsatile flow, and in a patient with minimal or no pulsatility, these devices either give wildly inaccurate readings or return an error. The accepted method is using a manual cuff with a Doppler ultrasound probe over the brachial artery. You inflate the cuff above the expected pressure and slowly deflate it while listening with the Doppler. The first sound you hear corresponds to the mean arterial pressure rather than a true systolic reading, because there is little distinction between systolic and diastolic in continuous flow.

Even this gold-standard Doppler technique has limitations. It provides only a single pressure value rather than separate systolic and diastolic numbers, which can make ongoing hemodynamic management more difficult.⁹ In the acute setting of a code, getting any reliable pressure reading is valuable, but clinicians should know that the number they obtain is a mean pressure, and target values are different from what they would aim for in a patient with a beating heart. Most LVAD programs target a mean arterial pressure below about 80-90 mmHg to protect against pump-related complications and stroke risk.

Calling the VAD Team Early

One of the most consistent recommendations across all published guidelines is to contact the patient’s LVAD center as early as possible. Early communication with the VAD team and appropriate consultants is essential for emergent care.⁷ Most LVAD patients carry identification cards or wear medical alert bracelets listing their implanting center and a 24-hour contact number for the VAD coordinator. The coordinator can walk unfamiliar clinicians through device-specific troubleshooting, interpret alarm codes, and advise on parameter adjustments that are not intuitive without training on that particular device platform.

This matters because LVAD systems are not identical. Different manufacturers use different controller interfaces, alarm systems, and battery configurations. A clinician trained on one device type may be unfamiliar with another’s alarm codes and power connections. The patient’s caregiver, if present, is also a critical resource. Patients and their designated caregivers receive extensive training before hospital discharge and can often provide device-specific guidance, change batteries, and interpret basic alarm patterns faster than an emergency team encountering the device for the first time.

Pre-Hospital and First Responder Challenges

LVAD patients who call 911 present a unique challenge for paramedics and EMTs. Despite the growing number of patients living at home with these devices, there is very little published literature specifically addressing out-of-hospital emergency care for LVAD patients.¹⁰ Most EMS training programs do not cover LVAD management in depth, and first responders arriving at a scene may never have encountered one of these devices before.

Compounding the problem, device-specific guidance has historically been inconsistent across implanting centers. In the UK, for example, multiple LVAD systems are implanted across several transplant centers, each of which provides its own device-specific information to local emergency services. This has led to inconsistent availability and content of information, with the risk of delayed or inappropriate decision-making in the field.¹¹ Efforts to standardize prehospital LVAD algorithms have been published, but adoption varies widely by region.

For first responders encountering an LVAD patient, the practical priorities are to ensure the device has power (check the batteries and controller), assess for signs of adequate perfusion using skin color and level of consciousness rather than pulse, and transport to a facility with LVAD expertise whenever possible. If the patient is in cardiac arrest with a non-functioning device, standard ACLS including compressions should not be withheld while waiting for VAD-specific guidance.

What the Survival Numbers Look Like

Cardiac arrest in an LVAD patient carries a sobering prognosis. A large analysis of U.S. hospital admissions between 2010 and 2018 identified over 93,000 hospitalizations involving implanted LVADs. Of those, 578 involved a cardiac arrest. Among the patients who received CPR, in-hospital mortality was about 74%.¹² Even among LVAD hospitalizations with cardiac arrest regardless of whether CPR was performed, mortality was roughly 61%. These are not encouraging numbers, but they also reflect the severity of illness in this population: these are patients whose hearts had already failed badly enough to require a mechanical pump.

The high mortality rate also underscores why identifying and treating reversible causes quickly is so critical. A patient whose arrest stems from a disconnected power cable has a very different prognosis than one whose arrest results from massive pump thrombosis or hemorrhagic stroke. Speed in diagnosis directly translates to survival in the subset of patients with fixable problems.

When Escalation to ECMO Becomes Necessary

In cases where standard resuscitation measures fail, extracorporeal membrane oxygenation can serve as a bridge therapy. Venoarterial ECMO is commonly used for extracorporeal CPR in refractory arrests, but its use in LVAD patients creates unique hemodynamic complexities because two mechanical circulatory support systems are now interacting. Alternative ECMO configurations, including venopulmonary and hybrid approaches, may provide more tailored support depending on whether the primary problem is right ventricular failure, respiratory failure, or both.¹³ These strategies are available only at specialized centers with both LVAD and ECMO expertise, which is another reason early transfer to an LVAD center matters.

End-of-Life Considerations and Device Deactivation

Not every LVAD arrest should be resuscitated. This is a difficult but important reality. Some LVAD patients have advanced directives specifying that they do not wish to undergo CPR, and some patients or their surrogates may request device deactivation when further treatment is no longer consistent with their goals of care. Because the LVAD is continuously sustaining circulation, turning it off is functionally different from withdrawing a medication or even discontinuing a ventilator. It will almost certainly result in death within minutes to hours.

The ethics of LVAD deactivation have been explored in medical literature, with frameworks proposed for navigating requests in situations without obvious medical or device-related complications.¹⁴ Questions about whether an LVAD is more like a treatment (which can be withdrawn) or more like an organ (which cannot) are not fully resolved, and practices vary by institution. What is consistent is the recommendation that these conversations happen well before a crisis, ideally at the time of LVAD implantation, so that the patient’s wishes are documented and accessible when a code occurs. If a patient has a do-not-resuscitate order and a clear statement about device deactivation, the emergency team needs to be able to access and honor those preferences even in a chaotic resuscitation scenario.

Practical Summary for Unfamiliar Clinicians

For clinicians who rarely encounter LVAD patients, the mental model during a code can be distilled into a sequence that diverges from standard ACLS in a few key places:

• Check the device first: Look at the controller for alarms and power status. Listen over the pump for a hum. A non-functioning device changes the entire approach.
• Assess perfusion without relying on pulse: Use skin color, capillary refill, and level of consciousness. A Doppler can confirm flow if available.
• Defibrillate shockable rhythms normally: The LVAD does not need to be turned off. Pad placement should avoid the device pocket if possible, but do not delay the shock.
• Start compressions if the device is off and the patient is pulseless: The risk of cannula injury exists, but the alternative is no forward flow at all.
• Think about LVAD-specific causes: Pump thrombosis, right heart failure, GI bleeding, driveline infection, and disconnected power are all on the differential before the standard H’s and T’s.
• Call the VAD center: The patient’s card or caregiver should have the number. The coordinator can troubleshoot remotely in real time.

The overarching theme is that LVAD arrests require you to think about the device as a second circulatory system, not just an incidental finding. The standard ACLS framework still applies for rhythm management and pharmacology, but the assessment, the decision to compress, and the differential diagnosis all shift in ways that can determine whether the patient survives.