Ambulatory Fontan pressure monitoring: Results from the implantable hemodynamic monitor Fontan feasibility cohort (IHM-FFC)

Use of the CardioMEMS Device in Children and Patients with Congenital Heart Disease: A Literature Review

The CardioMEMS HF System (Abbott, Abbott Park, IL) is the first FDA- and CE-Mark-approved device for monitoring patients with heart failure, significantly reducing hospitalizations and improving the quality of life for NYHA class III non-congenital adult patients. This device, implanted percutaneously, allows the direct monitoring of pulmonary arterial pressure with the wireless transfer of pressure data to the clinician, who can adjust the therapy remotely. Limited experience exists regarding its use in patients with congenital heart disease (CHD). CardioMEMS device implantation is feasible and safe in selected adults and children with CHD. The potential of the device to reduce heart failure hospitalizations in this population is enormous, but further multi-center studies are needed to demonstrate its efficacy.

Invasive Implanted Hemodynamic Monitoring in Patients With Complex Congenital Heart Disease: State-of-the-Art Review

As the number of patients with congenital heart disease (CHD) continues to increase, the burden of heart failure (HF) in this population requires innovative strategies to individualize management. Given the success of implanted invasive hemodynamic monitoring (IHM) with the CardioMEMSTM HF system in adults with acquired HF, this is often suggested for use in patients with CHD, though published data are limited to case reports and case series. Therefore, this review summarizes the available published reports on the use of IHM in patients with complex CHD, describes novel applications, and highlights future directions for study. In patients with CHD, IHM has been used across the lifespan, from age 3 years to adulthood, with minimal device-related complications reported. IHM uses include (1) prevention of HF hospitalizations; (2) reassessment of hemodynamics after titration of medical therapy without repeated cardiac catheterization; (3) serial monitoring of at-risk patients for pulmonary hypertension to optimize timing of heart transplant referral; (4) and hemodynamic assessment with exercise (5) or after ventricular assist device placement. IHM has the potential to reduce the number of cardiac catheterizations in anatomically complex patients and, in patients with Fontan circulation, IHM pressures may have prognostic implications. In conclusion, though further studies are needed, as patients with CHD age and HF is more prevalent, this tool may assist CHD physicians in caring for this complex patient population.

Transcatheter Interventions in Adult Congenital Heart Disease

Congenital heart disease (CHD) is the most common congenital birth defect with an incidence of 1 in 100. Current survival to adulthood is expected in 9 out of 10 children with severe CHD as the diagnostic, interventional, and surgical success improves. The adult CHD (ACHD) population is increasingly diverse, reflecting the broad spectrum of CHD and evolution of surgical techniques to improve survival. Similarly, transcatheter interventions have seen exponential growth and creativity to reduce the need for repeat sternotomies. This article focuses on newer data and evolving techniques for transcatheter interventions specific to certain ACHD populations.

Hemodynamic Monitoring of Pediatric Patients With Heart Failure and Pulmonary Hypertension Using CardioMEMS

Background

The CardioMEMS is an implantable device for hemodynamic monitoring approved by the US Food and Drug Administration for adult patients with heart failure. It has been used in the adult population without structural heart disease and with congenital heart diseases, but we do not have data in the pediatric population.

Methods

We report the initial single-center experience of the CardioMEMS implantation in children. Feasibility of device implantation, procedural outcomes, and clinical utility in the pediatric population were evaluated.

Results

The CardioMEMS device was implanted without technical complications in 8 pediatric patients (mean age 7 years and mean weight 27.9 kg) with pulmonary hypertension (6/8, 75%) and heart failure (2/8, 25%). The device was delivered via femoral access in 7 (85%) patients and implanted in the left pulmonary artery in 7 (85%). The noninvasive recording of pulmonary pressures in patients with pulmonary hypertension allowed the monitoring of the evolution of mean pulmonary artery pressure, intensifying vasodilator treatment, and avoiding control cardiac catheterizations. In patients with heart failure, pulmonary hemodynamic monitoring guided the decongestive treatment prior to heart transplantation.

Conclusions

The implantation of CardioMEMS in the pediatric population is a feasible procedure that allows the noninvasive hemodynamic monitoring of patients with heart failure and pulmonary hypertension. Its implementation in selected patients aids in outpatient follow-up and therapeutic management of patients with complex cardiac conditions, avoiding invasive procedures that require hospitalization. Further large-scale studies in the pediatric population are recommended.

Early Experience and Lessons Learned Using Implanted Hemodynamic Monitoring in Patients With Fontan Circulation

BACKGROUND

Data on the use of implanted hemodynamic monitoring (IHM) in patients with Fontan circulation are limited. This study reports our experience using the CardioMEMS HF system in adults with Fontan circulation.

METHODS AND RESULTS

This single-center, retrospective study evaluated heart failure hospitalizations, procedural complications, and device-related complications in patients with Fontan circulation referred for IHM placement (2015-2022). The association of pulmonary artery pressure (by most recent catheterization and median IHM pressure within 30 days of placement) with both death and follow-up Model for End-Stage Liver Disease Excluding International Normalized Ratio score were evaluated. Of 18 patients referred for IHM placement, 17 were successful (median age, 30 [range 21-48] years, 6 women). Procedural complications (access site hematomas, pulmonary artery staining) occurred in 3 patients, without device-related procedural complications. In follow-up (median, 35 [range, 6-83] months), 1 patient developed a pulmonary embolism (possibly device-related). Heart failure hospitalizations/year were similar before and after IHM (median, 1 [interquartile range, 0-1.0] versus 0.6 [0-2.3]; P=0.268), though only 46% of heart failure hospitalizations had associated IHM transmissions. IHM pressures were associated with Model for End-Stage Liver Disease Excluding International Normalized Ratio scores (R2=0.588, P<0.001), though catheterization pressures were not (R2=0.140, P=0.139). The long-term mortality rate was 53% in this cohort. On unadjusted survival analysis, IHM pressures ≥18 mm Hg were associated with mortality (log rank P=0.041), which was not reproduced with catheterization pressures (log rank P=0.764).

CONCLUSIONS

In patients with Fontan circulation, IHM did not reduce heart failure hospitalizations, though patient adherence to transmission was low. Device-related complications were low. IHM pressures may better represent real-life conditions compared with catheterization given associations with mortality and Model for End-Stage Liver Disease Excluding International Normalized Ratio score.

Are dynamic measurements of central venous pressure in Fontan circulation during exercise or volume loading superior to resting measurements?

BACKGROUND

The main objective measure to assess the health of the Fontan circulation is the pressure measurement of the superior vena cava or pulmonary arteries. We reviewed the literature for benefits of measuring resting pressure in the Fontan circuit and explored whether dynamic measurement by volume loading or exercise has the potential to refine this diagnostic tool.

METHODS

PubMed was searched for articles showing a relationship between resting post-operative central venous pressure or pulmonary artery pressure and Fontan failure. Relationships between post-operative central venous pressure or pulmonary artery pressure and volume loading changes, such as during exercise or volume loading during cardiac catheterization, were also queried.

RESULTS

A total of 44 articles mentioned relationships between resting central venous pressure or pulmonary artery pressure and Fontan failure. Only 26 included an analysis between the variables and only seven of those articles found pressure to be predictive of Fontan failure. Ten articles examined the relationship between exercise or volume loading and outcomes and demonstrated a large individual variation of pressures under these dynamic conditions.

CONCLUSIONS

Based on current literature, there is not a lot of strong evidence to show that elevated resting central venous pressure or pulmonary artery pressure is predictive of Fontan failure. Some individuals experience dramatic increases in central venous pressure or pulmonary artery pressure under increased loading conditions with exercise or bolus fluid infusion, while others experience increases closer to that of a healthy control population. Further studies are needed to examine whether more dynamic and continuous monitoring of systemic venous pressures might better predict outcomes in patients with Fontan circulation.

Novel Therapeutic Strategies in Heart Failure in Adult Congenital Heart Disease: of Medicines and Devices

PURPOSE OF REVIEW

This paper reviews the latest literature on the growing field of heart failure in the adult congenital heart disease population.

RECENT FINDINGS

After highlighting the increasing prevalence and a few of the unique potential causes, including the concept of early senescence, this review begins with novel medical management strategies such as the angiotensin II receptor blocker and neprilysin inhibitors and sodium glucose cotransporter-2 inhibitors. Then, it addresses the latest applications of percutaneous techniques like implantable hemodynamic monitoring, transcatheter pulmonary and aortic valve replacement, and mitral clips. Cardiac resynchronization therapy and novel lymphatic system imaging and intervention are then described. Finally, the use of mechanical support devices, temporary and durable, is discussed as well as heart and combined heart and liver transplantation. There have been recent exciting advances in the strategies used to manage adult congenital heart disease patients with heart failure. As this population continues to grow, it is likely we will see further rapid evolution in this field.

Safety and utility of CardioMEMS device for remote pulmonary artery monitoring in paediatric Fontan patients: a case series

Background

Patients with single ventricle congenital heart disease who undergo total cavo-pulmonary anastomosis (Fontan surgery) suffer from elevated pulmonary artery pressure (PAP), which leads to multiple adverse sequelae. Traditionally, the Fontan pressures are assessed via invasive haemodynamic catheterization that exposes these medically fragile patients to the risks of vascular injury and anaesthesia. While the CardioMEM remote PAP monitor has been extensively used in adults with heart failure, the safety of this device has not been established in children.

Case summary

We report safety and utility of this device in eight paediatric Fontan patients. Our patients ranged from 9 to 18 years of age. There were no reported complications related to the implantation of the CardioMEMS device in our population.

Discussion

This is the first case series of safety of CardioMEMS device in paediatric Fontan Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation patients. Our experience indicates that the device may be safely utilized for the management of Fontan-related complications in this vulnerable population.

Heart Failure in Complex Congenital Heart Disease of the Adult

PURPOSE OF REVIEW

Adult congenital heart disease (ACHD) patients have demonstrated improved survival, especially those with severely complex disease, mainly single-ventricle/Fontan physiology and those with a systemic right ventricle. We describe the heart failure phenotypes of complex CHD, reversible causes for heart failure, and considerations for advanced therapy.

RECENT FINDINGS

While initially marketed for application to patients with acquired causes for heart failure, newer devices and technologies have started to be used in the ACHD population. After reversible causes for heart failure in CHD are addressed, it is reasonable to consider use of new device-based technologies and orthotopic heart transplant (OHT) for end-stage disease. New heart failure technology and organ transplant should carefully be considered and applied in complex ACHD, where there may be significant improvement in morbidity and mortality.

Providing a framework of principles for conceptualising the Fontan circulation

The Fontan operation remains the final palliation for thousands of patients with complex congenital heart disease. By creating a Fontan circuit, control of cardiac output and congestion is wrested away from the ventricle and new haemodynamic forces take control. Understanding how to control the flow in the Fontan circuit will enable clinicians to improve patient management and possibly prevent future complications.

Conclusion

This review proposes a framework of principles to conceptualise the functionality and limitations of a Fontan circulation.

Smart Graft Monitoring After the Fontan Operation

The Fontan operation for children with congenital heart disease places them in a physiological state of mildly elevated systemic venous pressure and low-normal cardiac output. Consequently, close follow-up is imperative, yet currently no method is available to obtain Fontan pressures without direct measurements in the cardiac catheterization laboratory while supine and sedated. We hypothesize that by suturing the CardioMEMS sensor device into the Fontan conduit during the standard Fontan operation for a child with single ventricular physiology, clinicians can accurately retrieve Fontan pathway pressure measurements noninvasively during normal physiological states.