Management of Dialysis for Patients Receiving Mechanical Circulatory Support

Abstract

Mechanical circulatory support is used to augment circulatory flow in cardiogenic shock and end-stage heart failure. Support can last from hours for temporary mechanical circulatory support to years for durable mechanical circulatory support. The physiologic relationship of heart and kidney function and the epidemic of cardio-kidney-metabolic disease lead to frequent use of simultaneous mechanical circulatory support and extracorporeal KRT (dialysis). The need for dialysis can range from short periods of AKI in cardiogenic shock to long-term dialysis for individuals who receive left ventricular assist devices (LVADs) for destination therapy in advanced heart failure and progress to CKD G5 with replacement therapy. Changes in technology, clinical evidence, and organ transplantation have led to major changes in mechanical circulatory support use. With temporary mechanical circulatory support, devices and clinical situations vary widely, with intra-aortic balloon pumps, microaxial flow pumps, and venoarterial extracorporeal membrane oxygenation providing different levels of circulatory support. Considerations for dialysis, whether for AKI or CKD G5, are discussed. In durable mechanical circulatory support, LVADs are now used primarily for permanent therapy, and most LVAD recipients survive for more than 5 years, time in which kidney dysfunction can develop or progress. Outpatient dialysis with LVADs is performed for both AKI and for CKD G5, with in-center intermittent hemodialysis, peritoneal dialysis, or home hemodialysis. This article discusses considerations specific to dialysis in temporary and durable circulatory support, including the challenging aspects of volume management and complication risks. Concurrent mechanical circulatory support and dialysis present diverse clinical challenges in patients with complex medical needs. Meeting this challenge requires close cooperation and shared decision making incorporating cardiologists, nephrologists, other medical professionals, patients, and their caregivers.

Introduction

Mechanical circulatory support is the use of pumps to provide circulatory flow.¹ The entwined functions of the heart and kidneys, and the high prevalence of diseases affecting both organs, may lead to simultaneous mechanical circulatory support and extracorporeal KRT (referred to as dialysis, including filtration-based strategies).^2,3 This can range from short periods of cardiogenic shock complicated by AKI managed with temporary mechanical circulatory support and continuous dialysis, to years-long support of left ventricular assist device (LVAD) recipients who develop CKD G5. The clinical scenarios are united by the complexity of achieving homeostasis in multiorgan failure.

We first provide an overview of temporary and durable mechanical circulatory support as relevant to dialysis and then discuss inpatient and outpatient management.

Mechanical Circulatory Support Overview

Mechanical circulatory support can be divided into temporary and durable: Temporary devices are for short-term use in hospital (hours to weeks), while durable devices are implanted for long-term use (months or years).

Temporary Mechanical Circulatory Support

Devices used for temporary support are summarized in Table 1.⁴ Isolated left ventricular or right ventricular support, or biventricular support, can be provided.⁵ Cardiogenic shock and supportive use during some procedures are common indications.⁶ Hemodynamic goals are summarized in Table 2. Device support in shock is considered when hypoperfusion persists after optimization of preload and afterload and inotrope use.⁷ The best evidence for temporary mechanical support comes from the DanGer Shock trial, in which early microaxial flow pump use in ST-segment elevation myocardial infarction with cardiogenic shock reduced 6-month mortality, and this use is now guideline-recommended.^8,9

Table 1.

Temporary mechanical circulatory support devices and dialysis considerations

Device (Common Brand Name)	Indications	Level of Circulatory Support	Device Characteristics	Dialysis Considerations
Intra-aortic balloon pump	Cardiogenic shock, coronary ischemia, during high-risk PCI, bridge to durable mechanical circulatory support or heart transplantation, left ventricle unloading during venoarterial ECMO	Low (0.5–1 L/min)	ECG-gated counterpulsation (balloon in aorta inflates during diastole, deflates during systole), increasing cardiac output and coronary perfusion, and decreasing myocardial oxygen demand. Reduces left ventricular afterload	Intermittent hemodialysis, PD, CKRT, PIKRT can be used, depending on the clinical circumstances
Microaxial flow pumps (Impella)	Cardiogenic shock, high-risk PCI, bridge to durable mechanical circulatory support or heart transplantation, left ventricle unloading during venoarterial ECMO	Low to high (1–5.5 L/min)	Different device sizes support different flow rates. Smaller devices are placed percutaneously in femoral artery; surgical cut down may be needed for larger devices. Hemolysis causing hyperkalemia can occur	Intermittent hemodialysis, PD, CKRT, PIKRT can be used, depending on the clinical circumstances
Percutaneous centrifugal-flow left-atrial to aortic pump (TandemHeart)	Can be used for cardiogenic shock, high-risk PCI, bridge to durable mechanical circulatory support or transplantation, left ventricle unloading during venoarterial ECMO. Rarely used	High (4–5 L/min)	Requires atrial septal puncture. Usually placed through the femoral vein and artery. Rarely used as similar levels of support are achievable with less invasive microaxial flow pumps	Intermittent hemodialysis, PD, CKRT, PIKRT can be used, depending on the clinical circumstances
Venoarterial ECMO	Cardiogenic shock with or without respiratory failure, extracorporeal cardiopulmonary resuscitation	High (3–7 L/min)	Can provide very high outputs, can provide complete support in settings of biventricular failure. Increases left ventricular afterload. The left ventricle can become distended from retrograde flow, for which left ventricular support with an additional device is sometimes added	Usually CKRT. Can be connected to the ECMO circuit or a separate dialysis catheter can be used; practices vary with potential advantages for each option.98 PD has also been used successfully99

CKRT, continuous KRT; ECMO, extracorporeal membrane oxygenation; PCI, percutaneous coronary intervention; PD, peritoneal dialysis; PIKRT, prolonged intermittent KRT.

Table 2.

Overview of hemodynamic measures in durable and temporary mechanical circulatory support

Measure	Monitoring Method	Durable LVADs	Temporary Mechanical Circulatory Support
MAP	Arterial line, NIBPa	75–90 mm Hg37	60–80 mm Hg7
Systolic BP	Arterial line, NIBP	MAP used instead37	≥90 mm Hg in cardiogenic shock7
Pulse pressure	Arterial line, NIBP	Can reflect balance between native cardiac function (with aortic valve opening) and device support; increases can be a sign of myocardial recovery37	Can reflect balance between native cardiac function and device support; variable effects of different devices16
PAPi	Pulmonary artery catheter (pulmonary artery pulse pressure/right atrial pressure)	PAPi <1.85 is a sign of right ventricle dysfunction37	Lower numbers indicative of right ventricle dysfunction; <2 and <1.5 have been used as thresholds7,37
Pulmonary catheter wedge pressure	Pulmonary artery catheter	Goal <18 mm Hg, volume sensitive37,71	Goal <15 mm Hg, volume sensitive7
Central venous pressure	Pulmonary artery catheter or central venous catheter	Goal <12 mm Hg, volume sensitive37,71	Goal <12 mm Hg, volume sensitive7
Cardiac index	Intermittent thermodilution using pulmonary artery catheter. Noninvasive measures, using pulse contour analysis or other methods, have limited evidence in mechanical circulatory support7	>2.2 L/min per m2; low values may be due to insufficient intravascular volume, tamponade, or right ventricle dysfunction; monitored in early postoperative period and assessed subsequently as needed37,100	>2.2 L/min per m2 7
Systemic vascular resistance	Pulmonary artery catheters	Values <800 dynes×sec×cm−5 suggestive of vasoplegia or distributive shock, can benefit from vasopressors	Values<800 dynes×sec×cm−5 suggestive of vasoplegia or distributive shock, can benefit from vasopressors

LVAD, left ventricular assist devices; MAP, mean arterial pressure; NIBP, noninvasive BP measurement; PAPi, pulmonary artery pulsatility index.

^aNoninvasive BP measurement includes measurement using oscillometric devices if pulse is palpable or Doppler ultrasound if not.

Device choice in other cardiogenic shock settings will vary with patient characteristics, shock severity, and goals (recovery, bridge to cardiac transplant, long-term support).^5,7 The main complications of these devices are bleeding, thrombosis, and infection, and anticoagulation is generally required.⁷

Kidney Dysfunction in Temporary Mechanical Circulatory Support

AKI treated with dialysis is common in cardiogenic shock managed with temporary mechanical circulatory support. The better survival with early use of a microaxial flow pump in the DanGer Shock trial was accompanied by higher AKI treated by dialysis: 42% in the intervention group versus 27% in the control arm.⁸ This higher risk was not because of survival.¹⁰ A systematic review of circulatory support for cardiogenic shock found that one third of patients require dialysis and nearly two thirds of those on dialysis died in-hospital.² Venoarterial–extracorporeal membrane oxygenation (ECMO) is also associated with substantial risk of AKI treated with dialysis, with 44.9% risk in a systematic review (which combined venovenous-ECMO and venoarterial-ECMO).¹¹ Use of a microaxial flow pump with venoarterial-ECMO is associated with higher risk of AKI treated with dialysis than ECMO alone.¹² In a comparison of microaxial flow pumps with intra-aortic balloon pumps for cardiogenic shock, the risk of AKI treated by dialysis was nearly doubled with microaxial pumps.¹³ Residual confounding cannot be excluded.

Potential AKI contributors include pre-existing CKD, ischemic and inflammatory damage from cardiogenic shock and inciting events, and heme-pigment nephropathy.¹⁴ Hemolysis is a potential complication of all circulatory support devices.¹⁵ Risk varies among devices, indications, and level and duration of support, with microaxial flow pumps and ECMO causing significant hemolysis, and intra-aortic blood pumps having low risk.¹⁶ With microaxial pumps, hemolysis risk ranges from 0% to 48%.^15,17,18 With venoarterial-ECMO, severe hemolysis (plasma-free hemoglobin >500 mg/L) occurred in 4% in one cohort.¹⁹ Hemolysis can be reduced by decreasing pump speed (reducing flow) and by repositioning microaxial devices.¹⁶ Kidney damage is due to heme toxicity to proximal tubular cells, tubular obstruction from free hemoglobin, inflammation, and vasoconstriction.²⁰ Circulating free hemoglobin and heme cause systemic damage through thrombosis, inflammation, and oxidative stress.²¹

Durable Mechanical Circulatory Support

Durable devices are usually used for left ventricular support (LVADs) and improve survival, exertional capacity, and quality of life in refractory advanced heart failure.^22,23 LVADs are mostly used as permanent (destination) therapy in patients ineligible for heart transplantation, with a smaller proportion used in patients with potential for transplant listing (bridge to candidacy).^24–27 One LVAD is US Food and Drug Administration–approved: The HeartMate 3, a magnetically levitated centrifugal pump with reduced pump thrombosis, stroke, and hemorrhage risk and better survival (86% at 1 year and 64% at 5 years).^28–30 With improved survival, long-term complications have increased in importance, including development and progression of CKD.^31,32 Some patients still have HeartWare HVAD and HeartMate 2 devices.³³

LVADs extract blood from the left ventricle and return it to the ascending aorta, working in parallel to (and unloading) the left ventricle and increasing flow and arterial pressure (Figure 1).³⁴ The device provides continuous flow, although the HeartMate 3 has intrinsic pump speed variation to mitigate thrombosis in the device and ventricle.³⁵ This does not appreciably affect macrocirculatory or microcirculatory pulsatility.³⁶ Flow depends on the rotor speed and the pressure difference across the pump, which fluctuates with arterial pressure, intravascular volume and ventricular preload, and the cardiac cycle. Table 3 has information on device-derived metrics. Initial pump speed is set in the operating room to achieve adequate arterial pressure and systemic perfusion while avoiding excessive left ventricle unloading, which can lead to right ventricle dysfunction.³⁷

Figure 1.

Left ventricular assist device for durable mechanical circulatory support. The only device available for implantation in the United States is a centrifugal flow pump (the HeartMate 3). The arrows show the direction of blood flow through the centrifugal flow pump. Blood enters the pump from the left ventricle through the inflow cannula, which is inserted into the apex of the left ventricle. It is then pumped through the outflow graft to the ascending aorta. Typical parameters are on the right. The rotor speed is the modifiable device setting. Device flow is dependent on both this speed and the pressure across the device, as shown. Created in BioRender. Walther, C. (2025) BioRender.com/hkaclrw.

Table 3.

Device-derived metrics for the HeartMate 3 durable left ventricular assist devices

Metric	How Measured	Uses and Considerations
PI, dimensionless	Inferred from the variation in power to the pump.36,101 Represents cardiac pulsatility, with typical values from 1 to 10, with higher values indicating higher ventricular filling and pulsatility44	Does not seem to correlate with pulsatility in microcirculatory flow; if PI drops below a threshold, speed reduces to the minimum, followed by ramping to the set speed, to prevent ventricular suction.36,101
Pump flow (liters per minute)	Estimated using pump speed and power. Underestimates actual flow at high flow44	Alarm is sounded if pump flow is <2.5 L per minute.44 Possible causes include volume depletion, tamponade, right ventricle failure, and hypertension37
Power (Watts)	Power driving the rotor is measured	The only variable directly measured, used to calculate the PI and flow

Pulsatility index derivation differs among left ventricular assist devices. Ventricular suction events are when the inflow cannula is occluded by the ventricular septum or wall. PI, pulsatility index.

Postoperatively, cardiac index >2.2 L/min per m² and mean arterial pressure (MAP) 75–90 mm Hg is recommended.³⁷ Table 2 describes hemodynamic goals further. Neurohormonal blockade to maintain goal MAP is recommended, with avoidance of higher pressures to reduce risk of hemorrhagic stroke and to decrease afterload.^37,38 Anticoagulation with warfarin is generally used (INR 2–3). Antiplatelet therapy is no longer recommended with the HeartMate 3.³⁹

Clinical findings, echocardiography, and ramp tests (where speed is lowered to the minimum then raised) are used to optimize hemodynamics, symptoms, and left ventricle unloading. The normal speed is 4800–5600 RPM. Excessive speed can contribute to right ventricle dysfunction through higher right ventricular preload and left ventricular septal shift.^40,41 Increasing speed can lower pulmonary arterial and capillary wedge pressures, with marginal effects on right atrial pressure.⁴² However, individual responses to speed changes vary with volume status, right ventricular function, systemic and pulmonary arterial properties, and valvular lesions.

Suction events occur when decreased left ventricular dimension compromises flow. Decreased left ventricle dimension can be due to volume depletion or imbalance between filling and emptying of the left ventricle. This can cause right ventricle dysfunction, resulting in further reduction in left ventricle filling, and ultimately occlusion of the inflow cannula by the ventricular septum or wall.⁴³ The HeartMate 3 uses an algorithm to monitor for suction and reduces flow for a short time if needed, but it does not sound an alert unless there is low flow (<2 L/min).⁴⁴

Stroke and GI bleeding are major early complications.⁴⁵ Infection is the most common adverse event.⁴⁶ Driveline infections increase in frequency after 90 days and are a major long-term complication, usually treated with 6–8 weeks of intravenous antibiotics followed by chronic antibiotic suppression.^46,47

Kidney Dysfunction in Durable Mechanical Circulatory Support

Many LVAD recipients have pre-existing CKD, and early AKI and progressive kidney dysfunction are common.^48,49 The risk of severe kidney dysfunction (three-fold rise in serum creatinine or level >5 mg/dl postoperatively, or creatinine increase ≥2 mg/dl from baseline on follow-up, or need for dialysis) may increase with the HeartMate 3 device: Compared with the prior generation device, at 2 years, risk was 36% higher, although this was not statistically significant.⁵⁰

Right ventricular dysfunction can initiate a cycle of kidney dysfunction, volume overload, and right ventricular failure. With prolonged LVAD support, development of aortic insufficiency or mechanical complications (e.g., outflow graft obstruction) can lead to inadequate left ventricular unloading, causing right ventricular dysfunction and kidney dysfunction.

Hemolysis occurs with LVADs, with 1.2% of HeartMate 3 recipients and 2.2% of HeartMate 2 recipients having a serious hemolysis event in one trial.²⁹ Considerations for AKI and systemic damage from hemolysis discussed in the temporary mechanical circulatory support section also apply here, with the addition that chronic hemolysis is a possible contributor to long-term kidney dysfunction.

Inpatient Management of Dialysis in Mechanical Circulatory Support

Temporary Mechanical Circulatory Support

Continuous KRT (CKRT) or prolonged intermittent KRT (PIKRT) is preferred in hemodynamically unstable patients because of the slow solute and fluid removal.^51,52 Potential benefits of PIKRT are less resource utilization and more time off treatment for procedures or mobilization⁵¹; CKRT provides continuous volume, acid–base, and potassium control. Nephrologists must collaborate closely with cardiology on volume management. Intermittent hemodialysis can be considered in stable patients on temporary mechanical circulatory support, for example, while awaiting coronary revascularization. Otherwise, transition to intermittent hemodialysis usually follows discontinuation of circulatory support. Peritoneal dialysis (PD) is intrinsically prolonged and can be continued in individuals with CKD G5 who are already on it in many cases. In addition, PD has been effectively used for managing AKI and expanded use has been advocated.^53–55 Disadvantages of PD are imprecise control of ultrafiltration, high glucose exposure, and intraabdominal pressure.^55,56 In addition, lack of familiarity with PD use in critical care settings is a barrier to use.⁵⁵ Patients on PD are sometimes transferred to hemodialysis after recovery from critical illness, although this may often be unnecessary and undesirable.⁵⁷

Vascular access is an important consideration in PIKRT and CKRT. Existing tunneled catheters can be used. Use of arteriovenous fistula or grafts for CKRT has been reported in a single-center study.⁵⁸ However, this is not widely done and catheters are usually required.⁵²

Durable Mechanical Circulatory Support

Common scenarios requiring inpatient dialysis include severe AKI in the peri-implantation period or later in the clinical course, and hospitalizations in people who are dialysis-dependent. Right ventricular dysfunction can occur in the early postoperative period, when CKRT may be needed to remove volume, optimize right ventricle filling pressures, and interrupt the cycle. Mortality in individuals with LVADs on dialysis is high,^59,60 and when LVAD recipients progress to CKD G5, transplant eligibility and palliative care must be considered.

Initiating Dialysis for AKI in Mechanical Circulatory Support

There is no specific evidence to guide dialysis initiation in this setting, and usual considerations largely apply. However, avoiding volume overload and elevated cardiac filling pressures is particularly important and requires close collaboration between nephrology and cardiology.^7,32 Rapid dialysis initiation is needed if adequately dosed diuretics are inadequate, particularly after durable LVAD implantation as volume overload resulting in elevated filling pressures can contribute to devastating right ventricular dysfunction.⁶¹ In venoarterial-ECMO, volume removal may limit left ventricular distension and need for mechanical left ventricular unloading.⁶²

Weaning from Inpatient Dialysis for AKI in Mechanical Circulatory Support

In oliguria, increasing urine output is a clear sign of improvement. In nonoliguric AKI, decreases in serum creatinine and BUN can signal recovery. Urine output ≥400–500 ml/24 hours without diuretics have been found to be predictive of successful dialysis discontinuation in general intensive care unit populations.^63,64 Measurement of urine creatinine clearance over 2–24 hours can also provide evidence of recovery. Minimum creatinine clearances of 12–23 ml/min have been suggested for dialysis discontinuation in general ICU populations.^64,65 A recent trial showed that a kidney function–based intermittent hemodialysis discontinuation strategy worsened kidney recovery compared with an indications-only (electrolytes, acid–base, hypoxemia) approach, although this was a selected population excluding mechanical circulatory support.⁶⁶

Outpatient Management

Outpatient dialysis in durable mechanical circulatory support may be needed for severe AKI or CKD progression after device placement or rarely when LVADs are implanted in people on dialysis being considered for simultaneous heart–kidney transplantation.⁶⁷

Transition to outpatient care requires careful planning and education of the patient and caregiver.⁶⁸ Finding hemodialysis centers to accommodate LVAD recipients can be challenging. Outpatient dialysis requires close cooperation and responsibility delineation among the patient, caregiver, heart failure team, nephrologist, and dialysis team.⁶⁹ In-center hemodialysis, home hemodialysis, and PD have all been used.

The usual challenges—sufficient fluid removal, intradialytic hypotension, access complications, hypertension, infections, and rehospitalizations—are magnified in mechanical circulatory support. Prevention of late right ventricular dysfunction requires vigilant volume optimization (with ultrafiltration and possibly diuretics), neurohormonal blockade, and pump speed optimization.⁷⁰ Figure 2 provides an overview of volume optimization, extrapolated from studies of cardiac filling pressures in LVAD recipients.^31,42,71,72 For hemodialysis, the flexibility to extend sessions is important to limiting ultrafiltration rates.³² Most LVAD recipients take diuretics,³⁷ and these can be continued in those with residual kidney function.

Figure 2.

Hypothetical considerations for volume optimization by dialysis in LVAD recipients. Achievement of PCWP <18 mm Hg and CVP <12 mm Hg (along with cardiac index >2.2 L/min per m²) with LVAD support has been shown to be associated with lower readmission rates.⁷¹ Interpreting right and left heart function in LVADs in a 2×2 grid has been suggested by others, along with hypovolemia at low right and left heart filling pressures.^31,42,71,72 From a dialysis perspective, volume optimization, with avoidance of fluid overload and hypovolemia, are the goals (represented by the blue area). Arrows show potential direction of movement of pressures along the graph from volume intake and ultrafiltration. BiV, biventricular; CVP, central venous pressure; HTN, hypertension; LVAD, left ventricular assist device; PCWP, pulmonary capillary wedge pressure; RV, right ventricular.

Hemodialysis

Arteriovenous access is preferred over catheters given the lower risk of infection in the general dialysis population.^32,73,74 Both grafts and fistulas have been successfully created and used in LVAD recipients despite concerns about limited arterial pulsatility affecting fistula maturation.^73–77 Vessel preservation for arteriovenous access is important.⁷⁸

In-Center Hemodialysis

The patient and/or caregiver must manage LVAD connections, alarms, and power sources. They bring charged batteries, backup batteries, a mobile power unit, and a backup system controller. The dialysis unit provides a suitable location for mobile power plug-in, and staff should be educated about the device, the system controller and connections, power sources, alarms, and care escalation protocols so that they can assist the patient if needed.

BP measurement in LVAD recipients depends on the presence of pulsatility (Figure 3). If the pulse is palpable, systolic and diastolic BP can be measured using an oscillometric device. If the pulse is not palpable, a manual BP cuff is inflated on the upper arm, a Doppler probe is placed over the brachial artery, and the pressure at which flow is detected on cuff deflation is the opening pressure, which is close to the MAP with low pulse pressure.⁷⁹

Figure 3.

Possible pressure waveforms with LVAD support. (A) Discernible pulse pressure in a setting where left ventricular pressure increases above the aortic pressure; systolic and diastolic pressure may be measurable using an oscillometric device. (B) Absence of pulse pressure when aortic pressure is above peak left ventricular pressure; opening pressure with sphygmomanometer and Doppler device will be needed. AoP, aortic pressure; LVP, left ventricular pressure; MAP, mean arterial pressure.

Management of hypotension and syncope is like routine practice: assessment for signs and symptoms of specific causes, turning off ultrafiltration, moving the patient to a supine position with elevation of legs, and instilling small volumes of crystalloid. If they do not rapidly respond to these interventions, transfer to a hospital with advanced heart failure capabilities is needed for further evaluation and intervention, including echocardiogram, review of LVAD alarm logs, invasive or noninvasive hemodynamic pressure monitoring, inotropes, and other advanced interventions.⁸⁰ Low flow alarms can be a sign of hypovolemia, arrhythmia, or more serious problems,⁸⁰ and management should be similar to that done for hypotension and syncope.

Dialysis unit staff should be trained on cardiopulmonary resuscitation in LVAD recipients.⁸¹ In the absence of a palpable pulse, determination of cardiac arrest and return of circulation requires assessment of mental status, skin perfusion and capillary refill, and breathing.⁸² Cardiopulmonary resuscitation with chest compressions and defibrillation is recommended in unconscious individuals without evidence of sufficient perfusion, as risk of device dislodgement is low.^37,81,82

A case series reported on 11 LVAD recipients who underwent 544 outpatient dialysis sessions using tunneled central venous catheters.⁶⁹ Tolerance of intermittent hemodialysis was demonstrated, with 1.1% of sessions terminated early. However, rehospitalization was common for infection, volume overload, and stroke.⁶⁹ Protocols were created delineating patient, dialysis unit, and advanced heart failure center responsibilities. Maximum ultrafiltration rate was limited to 10 ml/kg per hour in the protocol, with instructions to contact the nephrologist to extend the treatment time to achieve dry weight if needed. Despite this, the patients in the case series exceeded this ultrafiltration rate 53% of the time, with some patients exceeding this rate for all treatments.⁶⁹ Mean arterial pressure goal of 60–90 mm Hg was set, and achieved MAP was 75 mm Hg, with patient averages ranging from 55 to 85 mm Hg.⁶⁹

Successful in-center hemodialysis has also been reported in individuals supported with total artificial hearts, which are infrequently used durable mechanical circulatory support devices that completely replace the function of the native heart.⁸³

Home Hemodialysis

Home hemodialysis has desirable characteristics for LVAD recipients, allowing for more frequent dialysis sessions to maintain euvolemia and limit ultrafiltration rate.⁸⁴ Home hemodialysis (4 times/week using a central venous catheter) was successfully used in a patient who suffered AKI after LVAD implantation.⁸⁵ He was readmitted twice for hypotension and once for a gastrointestinal bleed, but duration of home hemodialysis and survival are not reported.⁸⁵ Another report described 2 years of successful frequent home hemodialysis in an LVAD recipient using a tunneled catheter.⁴⁸ The case reports do not describe how BP was monitored at home. Successful monitoring of home BP in LVAD recipients has been done by teaching patients and caregivers to use oscillometric devices or Doppler probes and manual cuffs.⁸⁶

Peritoneal Dialysis

PD is an option with possible desirable contrasts with hemodialysis: slow volume and solute removal, lower risk of bloodstream infections, and preservation of residual kidney function.^32,87 However, concerns remain about infectious complications from the proximity of preperitoneal drivelines and PD catheter exit sites.⁸⁸

The most comprehensive description of PD is a single-center series of nine LVAD recipients.⁸⁹ All were on PD before LVAD implantation and continued it afterward; none underwent transplantation. Time on PD before LVAD ranged from approximately 1 week to 8 years, with a mean of 2 years.⁸⁹ Four of the nine experienced driveline infections during follow-up, three of nine had PD catheter infections, of which one also had peritonitis (fatal in the fourth month), and two had combined PD catheter and driveline infections. One died from right heart failure during the third month. Survival with continuation of LVAD and PD ranged from approximately 2 months to 7 years, with a mean of nearly 2 years.⁸⁹ Another report describes an LVAD recipient transitioned to PD from hemodialysis for hypotension, suction events, and bacteremia.⁹⁰ Successful transition from hemodialysis to PD early after LVAD implantation for AKI, followed by discontinuation of PD after kidney function recovered, has been reported.⁹¹

Anemia

Anemia and iron deficiency are common in LVAD recipients.^92,93 Goal hemoglobin levels and optimal treatment regimens are uncertain, but intravenous iron is commonly used.^37,93,94 Caution in using erythropoiesis-stimulating agents in LVAD recipients has been suggested because of concern for thrombosis and ischemic stroke.^95,96 Use of high-dose postoperative erythropoiesis-stimulating agents in LVAD recipients regardless of kidney function correlated with suspected pump thrombosis in a study of the HeartMate 2.⁹⁷ The risk–benefit balance of erythropoiesis-stimulating agents for anemia in LVAD recipients on dialysis are uncertain; however, successful use in this setting has been described, and careful use is reasonable.⁶⁹

Conclusion

The entwined nature of kidney and heart disease results in simultaneous use of mechanical circulatory support and dialysis. These are complex and challenging situations for which data are limited and clinical judgment is important. Understanding the basics of mechanical circulatory support will help nephrologists as they work closely with heart failure teams. Close communication and shared decision making are essential to providing the best care consistent with patient values.

Supplementary Material

jasn-37-596-s001.pdf ^{(1.9MB, pdf)}

Disclosures

Disclosure forms, as provided by each author, are available with the online version of the article at http://links.lww.com/JSN/F623.

Author Contributions

Conceptualization: Ajith P. Nair, Carl P. Walther.

Funding acquisition: Carl P. Walther.

Resources: Carl P. Walther.

Writing – original draft: Carl P. Walther.

Writing – review & editing: Ajith P. Nair, Carl P. Walther.

Funding

C.P. Walther: National Institute of Diabetes and Digestive and Kidney Diseases (K23DK122131).