Pulmonary hypertension related to left heart disease: Insight from a wireless implantable hemodynamic monitor

Management of Pulmonary Hypertension in the Context of Heart Failure with Preserved Ejection Fraction

PURPOSE OF REVIEW

To review the current evidence and modalities for treating pulmonary hypertension (PH) in heart failure with preserved ejection fraction (HFpEF).

RECENT FINDINGS

In recent years, several therapies have been developed that improve morbidity in HFpEF, though these studies have not specifically studied patients with PF-HFpEF. Multiple trials of therapies specifically targeting the pulmonary vasculature such as phosphodiesterase (PDE) inhibitors, prostacyclin analogs, endothelin receptor antagonists (ERA), and soluble guanylate cyclase stimulators have also been conducted. However, these therapies demonstrated lack of consistency in improving hemodynamics or functional outcomes in PH-HFpEF. There is limited evidence to support the use of pulmonary vasculature-targeting therapies in PH-HFpEF. The mainstay of therapy remains the treatment of the underlying HFpEF condition. There is emerging evidence that newer HF therapies such as sodium-glucose transporter 2 inhibitors and angiotensin-receptor-neprilysin inhibitors are associated with improved hemodynamics and quality of life of patients with PH-HFpEF. There is also a growing realization that more robust phenotyping PH and right ventricular (RV) function may hold promise for therapeutic strategies for patients with PH-HFpEF.

Sacubitril/valsartan affects pulmonary arterial pressure in heart failure with preserved ejection fraction and pulmonary hypertension

AIMS

Prior studies have not fully characterized the haemodynamic effects of the angiotensin receptor-neprilysin inhibitor (ARNI) sacubitril/valsartan in heart failure with preserved ejection fraction and pulmonary hypertension (HFpEF-PH). The aim of the Treatment of PH With Angiotensin II Receptor Blocker and Neprilysin Inhibitor in HFpEF Patients With CardioMEMS Device (ARNIMEMS-HFpEF) study is to assess pulmonary artery pressure (PAP) dynamics by means of implanted PAP monitors in patients with HFpEF-PH treated with sacubitril/valsartan.

METHODS AND RESULTS

This single-arm, investigator-initiated, interventional study included 14 consecutive ambulatory symptomatic HFpEF-PH patients who underwent CardioMEMS implantation prior to enrolment [mean ejection fraction 60.4 ± 7.2%, baseline mean PAP (mPAP) 33.9 ± 7.6 mmHg]. Daily PAP values were examined during three periods: a 6 week period after CardioMEMS implantation and before sacubitril/valsartan treatment (pre-ARNI), a 6 week period with sacubitril/valsartan treatment (ARNI ON), and a 6 week period of sacubitril/valsartan withdrawal (ARNI OFF). The primary endpoint was change in mPAP with and without sacubitril/valsartan. Secondary endpoints included changes in 6 min walking distance, B-line sum in lung ultrasound, and quality of life (QoL). During the study period, 1717 mPAP measurements were recorded. Between pre-ARNI vs. ARNI ON, mPAP significantly declined by -4.99 mmHg [95% confidence interval (CI) -5.55 to -4.43]. Between ARNI ON vs. ARNI OFF, mPAP significantly increased by +2.84 mmHg [95% CI +2.26 to +3.42]. Between pre-ARNI vs. ARNI ON, we found an improvement in 6 min walking distance, B-lines, and QoL. Mean loop diuretic management did not differ between periods.

CONCLUSIONS

Sacubitril/valsartan significantly reduced mPAP in patients with HFpEF-PH, independent of loop diuretic management, together with improvement in functional capacity, lung congestion, and QoL. Sacubitril/valsartan may be a therapeutic alternative in HFpEF-PH.

Left Heart Disease-Related Pulmonary Hypertension

Pulmonary hypertension (PH) due to left heart disease (LHD; group 2 PH) is a common complication of heart failure with reduced ejection fraction and heart failure with preserved ejection fraction and is often related to disease severity and duration of these diseases. PH due to LHD is associated with negative impact on outcomes in addition to worse symptoms and exercise capacity. Risk factors for group 2 PH are older age, hypertension, atrial fibrillation, and features of metabolic syndrome. The main mechanisms for group 2 PH are believed to be vascular remodeling secondary to sustained elevated intravascular pressure.

Improving Diuretic Response in Heart Failure by Implementing a Patient-Tailored Variability and Chronotherapy-Guided Algorithm

Heart failure is a major public health problem, which is associated with significant mortality, morbidity, and healthcare expenditures. A substantial amount of the morbidity is attributed to volume overload, for which loop diuretics are a mandatory treatment. However, the variability in response to diuretics and development of diuretic resistance adversely affect the clinical outcomes. Morevoer, there exists a marked intra- and inter-patient variability in response to diuretics that affects the clinical course and related adverse outcomes. In the present article, we review the mechanisms underlying the development of diuretic resistance. The role of the autonomic nervous system and chronobiology in the pathogenesis of congestive heart failure and response to therapy are also discussed. Establishing a novel model for overcoming diuretic resistance is presented based on a patient-tailored variability and chronotherapy-guided machine learning algorithm that comprises clinical, laboratory, and sensor-derived inputs, including inputs from pulmonary artery measurements. Inter- and intra-patient signatures of variabilities, alterations of biological clock, and autonomic nervous system responses are embedded into the algorithm; thus, it may enable a tailored dose regimen in a continuous manner that accommodates the highly dynamic complex system.

Management of Pulmonary Hypertension in Left Heart Disease

Pulmonary hypertension due to left heart diseases (PH-LHD) is the most prevalent form of pulmonary hypertension. It frequently complicates heart failure with reduced ejection fraction (HFrEF) or preserved ejection fraction (HFpEF) and negatively impacts prognosis, particularly when a precapillary component is present.

PH-LHD is distinctive from pulmonary arterial hypertension (PAH) even though both conditions may share some common characteristics. In addition, the mechanisms involved in the development of a precapillary component are yet to be fully clarified, in particular in PH due to HFpEF.

Several studies have been exploring PAH pathways as potential therapies for PH-LHD, but no PAH-approved drug has demonstrated efficacy in PH-LHD. Rather, some classes of drugs, such as endothelin-receptor antagonists or prostacycline-analogues, have been found to be harmful in patients with HF. Therefore, at present, the only established treatments for PH-LHD are those that target the heart as recommended in the international guidelines for HF. Based on current knowledge, off-label prescription of PAH-approved drugs in PH-LHD patients must be strongly discouraged.

Assessing hemodynamic response to submaximal exercise in pulmonary arterial hypertension patients using an implantable hemodynamic monitor

Pulmonary arterial hypertension (PAH) is a chronic, progressive disease that is incurable, even with effective therapy. Long-term outcome in PAH is best preserved by targeting hemodynamic improvements to reduce risk of subsequent right ventricular (RV) failure. Methods that can assess RV adaptation to stress have important implications to better understand an individual's physiology and may play a pivotal role in guiding therapy in PAH. In this novel pilot study, we evaluate the feasibility of monitoring hemodynamic response to 6-minute walk distance in patients with PAH using the CardioMEMS HF System.

Acute pulmonary pressure change after transition to sacubitril/valsartan in patients with heart failure reduced ejection fraction

Aims

Sacubitril/valsartan combines renin–angiotensin–aldosterone system inhibition with amplification of natriuretic peptides. In addition to well‐described effects, natriuretic peptides exert direct effects on pulmonary vasculature. The effect of sacubitril/valsartan on pulmonary artery pressure (PAP) has not been fully defined.

Methods and results

This was a retrospective case‐series of PAP changes following transition from angiotensin‐converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB) to sacubitril/valsartan in patients with heart failure reduced ejection fraction and a previously implanted CardioMEMS™ sensor. Pre‐sacubitril/valsartan and post‐sacubitril/valsartan PAPs were compared for each patient by examining averaged consecutive daily pressure readings from 1 to 5 days before and after sacubitril/valsartan exposure. PAP changes were also compared between patients based on elevated trans‐pulmonary gradients (trans‐pulmonary gradient ≥ 12 mmHg) at time of CardioMEMS™ sensor implantation. The cohort included 18 patients, 72% male, mean age 60.1 ± 13.6 years. There was a significant decrease in PAPs associated with transition from ACEI/ARB to sacubitril/valsartan. The median (interquartile range) pre‐treatment and post‐treatment change in mean, systolic and diastolic PAPs were −3.6 (−9.8, −0.7) mmHg (P < 0.001), −6.5 (−15.0, −2.0) mmHg (P = 0.001), and −2.5 (−5.7, −0.7) (P = 0.001), respectively. The decrease in PAPs was independent of trans‐pulmonary gradient (F(1,16) = 0.49, P = 0.49).

Conclusions

In this retrospective case series, transition from ACEI/ARB to sacubitril/valsartan was associated with an early and significant decrease in PAPs.

Wireless Hemodynamic Monitoring in Patients with Heart Failure

Purpose of Review

Wireless hemodynamic monitoring in heart failure patients allows for volume assessment without the need for physical exam. Data obtained from these devices is used to assist patient management and avoid heart failure hospitalizations. In this review, we outline the various devices, mechanisms they utilize, and effects on heart failure patients.

Recent Findings

New applications of these devices to specific populations may expand the pool of patients that may benefit. In the COVID-19 pandemic with a growing emphasis on virtual visits, remote monitoring can add vital ancillary data.

Summary

Wireless hemodynamic monitoring with a pulmonary artery pressure sensor is a highly effective and safe method to assess for worsening intracardiac pressures that may predict heart failure events, giving lead time that is valuable to keep patients optimized. Implantation of this device has been found to improve outcomes in heart failure patients regardless of preserved or reduced ejection fraction.

Pulmonary Hypertension Due to Left Heart Disease-A Practical Approach to Diagnosis and Management

Pulmonary hypertension (PH) due to left heart disease (LHD) is a frequent complication of heart failure (HF) and is associated with exercise intolerance, poor quality of life, increased risk of hospitalisations, and reduced overall survival. Since the recent Sixth World Symposium on Pulmonary Hypertension in 2018, there have been significant changes in the hemodynamic definitions and clinical classification of PH-LHD. PH-LHD can be subdivided into (1) isolated postcapillary PH (IpcPH) and (2) combined precapillary and postcapillary PH (CpcPH). This categorisation of PH-LHD is important because CpcPH shares certain pathophysiologic, clinical, and hemodynamic characteristics with pulmonary arterial hypertension and is associated with worse outcomes compared with IpcPH. A systematic approach using clinical history and noninvasive investigations is required in the diagnosis of PH-LHD. Right heart catheterisation with and without provocative testing is performed in expert centres and is indicated in selected individuals. Although the definition of IpcPH and CpcPH is based on measurements made with right heart catheterisation, distinguishing between these two entities is not always necessary. Despite strong evidence for medical therapy in patients with pulmonary arterial hypertension, those options have limited benefit in PH-LHD. Expert PH centres in Canada have been established to provide ongoing care for the more complex patient subgroups.

Use of eHealth in the management of pulmonary arterial hypertension: review of the literature

Background

Pulmonary arterial hypertension (PAH) is a severe chronic condition associated with poor quality of life and high risks of mortality and hospitalisation. The utilisation of novel diagnostic technologies has improved survival rates although the effectiveness of Electronic Health (eHealth) interventions in patients with a chronic cardiopulmonary disease remains controversial. As the effectiveness of eHealth can be established by specific evaluation for different chronic health conditions, the aim of this study was to explore and summarise the utilisation of eHealth in PAH.

Method

We searched PubMed, CINAHL and Embase for all studies reporting clinical trials on eHealth solutions for the management of PAH. No limitations in terms of study design or date of publication were imposed.

Results

18 studies (6 peer-reviewed journal papers and 12 conference papers) were identified. Seven studies addressed the accuracy, safety or reliability of eHealth technologies such as intra-arterial haemodynamic monitoring of the pulmonary artery pressure, self-administered 6-Minute walk test App, computerised step-pulse oximeter and ambulatory impedance cardiography. Two studies evaluated eHealth as part of the medical management and showed a reduction in hospitalisation rate.

Conclusions

The evidence of eHealth supporting the management of people with PAH is limited and only embraced through a few studies of small sample size and short-term duration. Given the proposed clinical benefits in heart failure, we postulate that the evaluation of eHealth for the clinical management of PAH is highly warranted.

Pulmonary arterial hypertension and heart failure with preserved ejection fraction: are they so discordant?

Heart failure with preserved ejection fraction (HFpEF) and pulmonary arterial hypertension (PAH) are two emerging diseases focusing the attention of numerous researchers. In the last PAH guideline, there is a crossroad between the two diseases and pulmonary hypertension (PH) due to heart failure (HF) is categorized as subtype 2. In order to assess the correct diagnosis and management, it should be better understood the points of convergence and divergence of two diseases. Although, risk factors, demographic characteristics and haemodynamics are different, we report several similarities regarding vascular alterations, some aspects of cardiac remodelling, and clinical presentation. This model suggests HFpEF and PAH as two comparable conditions, with different cardiac adaptation and trajectories, linked to the intrinsic properties of either right and left ventricles. In both diseases the early pathophysiological mechanisms appear to begin from peripheral vasculature and to be backward transmitted to the larger arterial vascular district, and eventually to the myocardial structure. In this paper we would propose a simple approach to recognize the concordances and, all at once, distinguish the peculiarities of the two diseases.

Off-label use of pulmonary vasodilators after left ventricular assist device implantation: Calling in the evidence

Left ventricular assist devices (LVAD) are increasingly implanted in advanced heart failure patients to improve survival and quality of life either as a bridge to transplant, bridge to recovery or as destination therapy. LVAD therapy is often accompanied by a profound lowering of pulmonary artery pressure due to mechanical unloading of the left ventricle. Persistent pulmonary hypertension (PH) after LVAD implantation increases the risk of right ventricular failure (RVF). In this context pulmonary vasodilators have been implemented: a) as a strategy to reduce afterload and wean patients with RVF from inotropes in the early postoperative period, b) as long-term therapy aiming to optimize right heart hemodynamics and prevent late RVF and c) in order to lower persistently elevated pulmonary artery pressure (PAP) and pulmonary vascular resistance (PVR) after LVAD and enable candidacy for heart transplantation. However, considerable uncertainty exists regarding the risks and benefits of these strategies and practices vary widely among institutions. This article provides an overview of the available evidence and existing recommendations regarding the use of pulmonary vasodilators in LVAD recipients.

CardioMEMSTM System in the Daily Management of Heart Failure: Review of Current Data and Technique of Implantation

INTRODUCTION

Heart failure (HF) leads to significant morbidity and mortality and imposes a large economic burden. Although there have been several advances in HF monitoring and management, HF-rehospitalization remains a significant problem. Remote monitoring of HF to detect early signs of decompensation has emerged in past years as an option to prevent or reduce the incidence of HF rehospitalization. The CardioMEMS^TM HF system is a wireless pulmonary artery (PA) pressure monitoring system that detects changes in PA pressure and transmits data to the healthcare provider. Since changes in PA pressure happen early in the course of HF decompensation, the CardioMEMS^TM system allows the provider to institute timely intensification of HF therapies to alter the course. In trial and registry data, the use of the CardioMEMS^TM HF system has been associated with reduction in HF hospitalization, improvement in quality of life, symptoms, and physical activity.

AREAS COVERED

This review will focus on the available data supporting its utilization in patients with HF.

EXPERT OPINION

CardioMEMS^TM is relatively safe and cost-effective, reduces heart failure hospitalization rates, and fits into intermediate to high-value medical care.

Integrated use of cardiac MRI and the CardioMEMS™ HF system in PAH: the utility of coincident pressure and volume in RV failure-the NHLBI-VITA trial

Background

This study aims to study the feasibility and safety of measuring volumetric and pressure parameters noninvasively using simultaneous cardiovascular magnetic resonance (cMR) volumetric data and time-resolved pressure waveforms from previously implanted CardioMEMS devices in pulmonary arterial hypertension (PAH) patients. Opportunities to intervene during clinically occult phases in PAH promise to herald a key transformation in our current practice for treating this complex population. Currently, it is possible and convenient to monitor daily pulmonary arterial (PA) pressures in PAH patients using the CardioMEMS device to determine clinically silent progression. Supplementation of these pressures with other prognostic measurements of right ventricular (RV) contractility, PA resistance and RV/PA coupling could add further predictive capabilities.

Methods

PAH patients (n=17) with New York Hospital Association (NYHA) class III or IV heart failure (HF) and recent HF related hospitalizations were implanted with the CardioMEMS device as part of a NHLBI sponsored Trial. Implanted patients were then assessed using cMR imaging of the right ventricle (RV) along with measurement of pulmonary artery flow. Patients were imaged at one-month post implant (baseline) and at 4-month follow-up time (n=12). At baseline, patients were studied at rest and then under three different physiologic conditions: inhaled nitric oxide (INO), dobutamine (Dob) stress and volumetric stress (Vol), using a multiple slice short-axis imaging and a rapid imaging protocol.

Results

All patients were safely imaged, with no artifacts obscuring the cMR images. RV volumes were measured successfully at rest and under each stress condition using a reduced scan approach that required calibration for each patient which achieved a correlation r² of 0.98. Variables measured included the maximal pulmonary artery elastance (Ea), maximal RV myocardial elastance (Emax) and ventricular-vascular coupling ratio (VVC). The response to stressors was determined on a patient basis. No complications occurred during the cMRI examination.

Conclusions

It is safe and feasible to perform cMR imaging with simultaneous pulmonary artery pressure readings from the CardioMEMS device. A reduced scan approach was developed to allowed measurement of RV volumes during stress conditions. Volumetric and pressure measurements can be combined to assess fundamental myocardial properties (e.g., Emax, Ea and VVC) in PAH patients serially over time. In the future, these parameters can be tested as serial predictors of outcome and response to therapies in PAH.

CardioMEMS: where we are and where can we go?

The prevalence of heart failure (HF) has been on the rise with associated increase in hospitalizations, morbidity and mortality. These hospitalizations have led to increasingly more cost on and decreased quality of life for patients. CardioMEMS is one of the newer devices designed to help tackle this issue by allowing for better monitoring of HF patients. This device also allows for accurate recording of pulmonary artery pressures (PAPs) and has also been applied in various other areas, such as aneurysmal tears, for monitoring pressures. In this manuscript we will review the current state of CardioMEMS HF system and investigate some of the other areas for its promising use in the field.

Monitoring Pulmonary Arterial Hypertension Using an Implantable Hemodynamic Sensor

BACKGROUND

Pulmonary arterial hypertension (PAH) is a chronic disease that ultimately progresses to right-sided heart failure (HF) and death. Close monitoring of pulmonary artery pressure (PAP) and right ventricular (RV) function allows clinicians to appropriately guide therapy. However, the burden of commonly used methods to assess RV hemodynamics, such as right heart catheterization, precludes frequent monitoring. The CardioMEMS HF System (Abbott) is an ambulatory implantable hemodynamic monitor, previously only used in patients with New York Heart Association (NYHA) class III HF. In this study, we evaluate the feasibility and early safety of monitoring patients with PAH and right-sided HF using the CardioMEMS HF System.

METHODS

The CardioMEMS HF sensors were implanted in 26 patients with PAH with NYHA class III or IV right-sided HF (51.3 ± 18.3 years of age, 92% women, 81% NYHA class III). PAH therapy was tracked using a minimum of weekly reviews of CardioMEMS HF daily hemodynamic measurements. Safety, functional response, and hemodynamic response were tracked up to 4 years with in-clinic follow-ups.

RESULTS

The CardioMEMS HF System was safely used to monitor PAH therapy, with no device-related serious adverse events observed and a single preimplant serious adverse event. Significant PAP reduction and cardiac output elevation were observed as early as 1 month postimplant using trends of CardioMEMS HF data, coupled with significant NYHA class and quality of life improvements within 1 year.

CONCLUSIONS

The CardioMEMS HF System provided useful information to monitor PAH therapy, and demonstrated short- and long-term safety. Larger clinical trials are needed before its widespread use to guide therapy in patients with severe PAH with right-sided HF.

Intersection of Pulmonary Hypertension and Right Ventricular Dysfunction in Patients on Left Ventricular Assist Device Support: Is There a Role for Pulmonary Vasodilators?

Left ventricular assist devices (LVADs) improve survival and quality of life in patients with advanced heart failure. Despite these benefits, combined post- and precapillary pulmonary hypertension can be particularly problematic in patients on LVAD support, often exacerbating right ventricular (RV) dysfunction. Both persistently elevated pulmonary vascular resistance and RV dysfunction are associated with adverse outcomes, including death after LVAD. These observations have led to significant interest in the use of pulmonary vasodilators to treat pulmonary hypertension and preserve RV function among LVAD-supported patients. Although pulmonary vasodilators are commonly used for the treatment of pulmonary hypertension and RV dysfunction in LVADs, the benefits of this practice remain unclear. The purpose of this review is to highlight the current challenges in managing pulmonary vascular disease and RV dysfunction in patients with heart failure on LVAD support.

Chronic heart failure management and remote haemodynamic monitoring

Heart failure (HF) has a large societal and economic burden and is expected to increase in magnitude and complexity over the ensuing years. A number of telemonitoring strategies exploring remote monitoring and management of clinical signs and symptoms of congestion in HF have had equivocal results. Early studies of remote haemodynamic monitoring showed promise, but issues with device integrity and implantation-associated adverse events hindered progress. Nonetheless, these early studies established that haemodynamic congestion precedes clinical congestion by several weeks and that remote monitoring of intracardiac pressures may be a viable and practical management strategy. Recently, the safety and efficacy of remote pulmonary artery pressure-guided HF management was established in a prospective, single-blind trial where randomisation to active pressure-guided HF management reduced future HF hospitalisations. Subsequent commercial use studies reinforced the utility of this technology and post hoc analyses suggest that tight haemodynamic management of patients with HF may be an additional pillar of therapy alongside established guideline-directed medical and device therapy. Currently, there is active exploration into utilisation of this technology and management paradigm for the timing of implantation of durable left ventricular assist devices (LVAD) and even optimisation of LVAD therapy. Several ongoing clinical trials will help clarify the extent and utility of this strategy along the spectrum of patient with HF from individuals with chronic, stable HF to those with more advanced disease requiring heart replacement therapy.

Right heart dysfunction: from pathophysiologic insights to therapeutic options: a translational overview

: The right ventricle has become increasingly studied in cardiovascular research. In this article, we describe specific pathophysiological characteristics of the right ventricle, with special focus on functional and molecular modifications as well as therapeutic strategies in right ventricular dysfunction, underlining the differences with the left ventricle. Then we analyze the main imaging modalities to assess right ventricular function in different clinical settings. Finally, we acknowledge main therapeutic advances for treatment of right heart diseases.

Baseline diastolic pressure gradient and pressure reduction in chronic heart failure patients implanted with the CardioMEMS™ HF sensor

AIMS

Remote haemodynamic monitoring (RHM) decreases hospitalization rates in patients with chronic heart failure (HF). Many patients with chronic HF develop pulmonary hypertension (PH) secondary to left heart disease with some acquiring combined pre-capillary and post-capillary PH (Cpc-PH). The efficacy of RHM in achieving pulmonary pressure reductions in patients with Cpc-PH vs. isolated post-capillary PH (Ipc-PH) is unknown. The purpose of this study is to evaluate whether a higher baseline diastolic pressure gradient (DPG_baseline ) measured at the time of CardioMEMS™ HF sensor implantation is associated with lower reductions in pulmonary artery diastolic pressures (PADP).

METHODS AND RESULTS

This was a retrospective analysis of 32 patients meeting clinical indications for CardioMEMS™ implantation. DPG_baseline categorized patients as Cpc-PH (DPG ≥ 7 mmHg) or Ipc-PH (DPG < 7 mmHg). Minimum achievable PADP (PADP_min ) and ∆PADP (PADP_baseline  - PADP_min ) were determined. Pearson's correlation analysis and comparison of mean pressure changes were assessed. Median age was 69 years, and median left ventricular ejection fraction (LVEF) was 25%. Eight patients (25%) had a LVEF ≥40%. Twenty-five patients (78%) met criteria for Ipc-PH and seven (22%) for Cpc-PH. Neither PADP_min (ρ = 0.27; P = 0.13) nor ΔPADP (ρ = 0.07; P = 0.72) was correlated with DPG_baseline . A trend towards higher ΔPADP was seen in Cpc-PH vs. Ipc-PH patients (15.2 vs. 9.88 mmHg; P = 0.12). There was a moderate positive correlation between baseline PADP and ΔPADP [ρ = 0.55 (0.26-0.76); P < 0.001].

CONCLUSIONS

Decreased PADP reduction was not seen in Cpc-PH vs. Ipc-PH patients. Higher PADP_baseline was associated with greater ΔPADP. Larger studies are needed to elaborate our findings.

Pulmonary Hypertension in the Era of Mechanical Circulatory Support

Left heart disease (LHD) represents the most common cause of pulmonary hypertension (PH), and is associated with worse prognosis compared with LHD without PH. In addition, PH due to LHD may prevent patients from receiving heart transplantation, because of risk of perioperative right ventricular failure. Current literature lacks comprehensive descriptions and management strategies of PH due to LHD. In this review, we summarize the literature that is available to highlight the definition, pathogenesis, and prognosis of PH due to LHD. Furthermore, we discuss the use of mechanical circulatory support (MCS) in this population. Finally, we provide recommendations regarding the management and reassessment of PH due to LHD in the specific context of MCS.

Decoupling Between Diastolic Pulmonary Artery Pressure and Pulmonary Capillary Wedge Pressure as a Prognostic Factor After Continuous Flow Ventricular Assist Device Implantation

BACKGROUND

A cohort of heart failure (HF) patients receiving left ventricular assist devices (LVADs) has decoupling of their diastolic pulmonary artery pressure and pulmonary capillary wedge pressure. However, the clinical implications of this decoupling remain unclear.

METHODS AND RESULTS

In this prospective study, patients with LVADs underwent routine invasive hemodynamic ramp testing with right heart catheterization, during which LVAD speeds were adjusted. Inappropriate decoupling was defined as a >5 mm Hg difference between diastolic pulmonary artery pressure and pulmonary capillary wedge pressure. The primary outcomes of survival and heart failure readmission rates after ramp testing were assessed. Among 63 LVAD patients (60±12 years old and 25 female [40%]), 27 patients (43%) had inappropriate decoupling at their baseline speed. After adjustment of their rotation speed during ramp testing, 30 patients (48%) had inappropriate decoupling. Uni/multivariable Cox analyses demonstrated that decoupling was the only significant predictor for the composite end point of death and heart failure readmission during the 1 year following the ramp study (total of 18 events; hazards ratio, 1.09; 95% confidence interval, 1.04-1.24; P<0.05). Furthermore, normalization of decoupling (n=8) during ramp testing was significantly associated with higher 1-year heart failure readmission-free survival rate compared with the non-normalized group (n=19, 100% versus 53%; P=0.035).

CONCLUSIONS

The presence of inappropriate decoupling was associated with worse outcomes in patients with LVADs. Prospective, large-scale multicenter studies to validate the result are warranted.

Implantable Hemodynamic Monitoring for Heart Failure Patients

Rates of heart failure hospitalization remain unacceptably high. Such hospitalizations are associated with substantial patient, caregiver, and economic costs. Randomized controlled trials of noninvasive telemedical systems have failed to demonstrate reduced rates of hospitalization. The failure of these technologies may be due to the limitations of the signals measured. Intracardiac and pulmonary artery pressure-guided management has become a focus of hospitalization reduction in heart failure. Early studies using implantable hemodynamic monitors demonstrated the potential of pressure-based heart failure management, whereas subsequent studies confirmed the clinical utility of this approach. One large pivotal trial proved the safety and efficacy of pulmonary artery pressure-guided heart failure management, showing a marked reduction in heart failure hospitalizations in patients randomized to active pressure-guided management. "Next-generation" implantable hemodynamic monitors are in development, and novel approaches for the use of this data promise to expand the use of pressure-guided heart failure management.

Pulmonary Vascular Distensibility Predicts Pulmonary Hypertension Severity, Exercise Capacity, and Survival in Heart Failure

BACKGROUND

Pulmonary vascular (PV) distensibility, defined as the percent increase in pulmonary vessel diameter per mm Hg increase in pressure, permits the pulmonary vessels to increase in size to accommodate increased blood flow. We hypothesized that PV distensibility is abnormally low in patients with heart failure (HF) and serves as an important determinant of right ventricular performance and exercise capacity.

METHODS AND RESULTS

Patients with HF with preserved ejection fraction (n=48), HF with reduced ejection fraction (n=55), pulmonary arterial hypertension without left heart failure (n=18), and control subjects (n=30) underwent cardiopulmonary exercise testing with invasive hemodynamic monitoring and first-pass radionuclide ventriculography. PV distensibility was derived from 1257 matched measurements (mean±SD, 8.3±2.8 per subject) of pulmonary arterial pressure, pulmonary arterial wedge pressure and cardiac output. PV distensibility was lowest in the pulmonary arterial hypertension group (0.40±0.24% per mm Hg) and intermediate in the HF with preserved ejection fraction and HF with reduced ejection fraction groups (0.92±0.39 and 0.84±0.33% per mm Hg, respectively) compared to the control group (1.39±0.32% per mm Hg, P<0.0001 for all three). PV distensibility was associated with change in right ventricular ejection fraction (RVEF, ρ=0.39, P<0.0001) with exercise and was an independent predictor of peak VO2. PV distensibility also predicted cardiovascular mortality independent of peak VO2 in HF patients (n=103; Cox hazard ratio, 0.30; 95% confidence interval, 0.10-0.93; P=0.036). In a subset of patients with HF with reduced ejection fraction (n=26), 12 weeks of treatment with the pulmonary vasodilator sildenafil or placebo led to a 24.6% increase in PV distensibility (P=0.015) in the sildenafil group only.

CONCLUSIONS

PV distensibility is reduced in patients with HF and pulmonary arterial hypertension and is closely related to RV systolic function during exercise, maximal exercise capacity, and survival. Furthermore, PV distensibility is modifiable with selective pulmonary vasodilator therapy and may represent an important target for therapy in selected HF patients with pulmonary hypertension.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00309790.

Pulmonary artery pressure-guided heart failure management: US cost-effectiveness analyses using the results of the CHAMPION clinical trial

AIMS

Haemodynamic-guided heart failure (HF) management effectively reduces decompensation events and need for hospitalizations. The economic benefit of clinical improvement requires further study.

METHODS AND RESULTS

An estimate of the cost-effectiveness of haemodynamic-guided HF management was made based on observations published in the randomized, prospective single-blinded CHAMPION trial. A comprehensive analysis was performed including healthcare utilization event rates, survival, and quality of life demonstrated in the randomized portion of the trial (18 months). Markov modelling with Monte Carlo simulation was used to approximate comprehensive costs and quality-adjusted life years (QALYs) from a payer perspective. Unit costs were estimated using the Truven Health MarketScan database from April 2008 to March 2013. Over a 5-year horizon, patients in the Treatment group had average QALYs of 2.56 with a total cost of US$56 974; patients in the Control group had QALYs of 2.16 with a total cost of US$52 149. The incremental cost-effectiveness ratio (ICER) was US$12 262 per QALY. Using comprehensive cost modelling, including all anticipated costs of HF and non-HF hospitalizations, physician visits, prescription drugs, long-term care, and outpatient hospital visits over 5 years, the Treatment group had a total cost of US$212 004 and the Control group had a total cost of US$200 360. The ICER was US$29 593 per QALY.

CONCLUSIONS

Standard economic modelling suggests that pulmonary artery pressure-guided management of HF using the CardioMEMS™ HF System is cost-effective from the US-payer perspective. This analysis provides the background for further modelling in specific country healthcare systems and cost structures.

Impact of Practice-Based Management of Pulmonary Artery Pressures in 2000 Patients Implanted With the CardioMEMS Sensor

Background:

Elevated pulmonary artery (PA) pressures in patients with heart failure are associated with a high risk for hospitalization and mortality. Recent clinical trial evidence demonstrated a direct relationship between lowering remotely monitored PA pressures and heart failure hospitalization risk reduction with a novel implantable PA pressure monitoring system (CardioMEMS HF System, St. Jude Medical). This study examines PA pressure changes in the first 2000 US patients implanted in general practice use.

Methods:

Deidentified data from the remote monitoring Merlin.net (St. Jude Medical) database were used to examine PA pressure trends from the first consecutive 2000 patients with at least 6 months of follow-up. Changes in PA pressures were evaluated with an area under the curve methodology to estimate the total sum increase or decrease in pressures (mm Hg-day) during the follow-up period relative to the baseline pressure. As a reference, the PA pressure trends were compared with the historic CHAMPION clinical trial (CardioMEMS Heart Sensor Allows Monitoring of Pressure to Improve Outcomes in New York Heart Association [NYHA] Functional Class III Heart Failure Patients). The area under the curve results are presented as mean±2 SE, and P values comparing the area under the curve of the general-use cohort with outcomes in the CHAMPION trial were computed by the t test with equal variance.

Results:

Patients were on average 70±12 years old; 60% were male; 34% had preserved ejection fraction; and patients were followed up for an average of 333±125 days. At implantation, the mean PA pressure for the general-use patients was 34.9±10.2 mm Hg compared with 31.3±10.9 mm Hg for CHAMPION treatment and 32.0±10.5 mm Hg for CHAMPION control groups. The general-use patients had an area under the curve of −32.8 mm Hg-day at the 1-month time mark, −156.2 mm Hg-day at the 3-month time mark, and −434.0 mm Hg-day after 6 months of hemodynamic guided care, which was significantly lower than the treatment group in the CHAMPION trial. Patients consistently transmitted pressure information with a median of 1.27 days between transmissions after 6 months.

Conclusions:

The first 2000 general-use patients managed with hemodynamic-guided heart failure care had higher PA pressures at baseline and experienced greater reduction in PA pressure over time compared with the pivotal CHAMPION clinical trial. These data demonstrate that general use of implantable hemodynamic technology in a nontrial setting leads to significant lowering of PA pressures.

Hemodynamic-guided heart-failure management using a wireless implantable sensor: Infrastructure, methods, and results in a community heart failure disease-management program

BACKGROUND

The real-world impact of remote pulmonary artery pressure (PAP) monitoring on New York Heart Association (NYHA) class improvement and heart failure (HF) hospitalization rate is presented here from a single center.

HYPOTHESIS

METHODS: Seventy-seven previously hospitalized outpatients with NYHA class III HF were offered PAP monitoring via device implantation in a multidisciplinary HF-management program. Prospective effectiveness analyses compared outcomes in 34 hemodynamically monitored patients to a group of similar patients (n = 32) who did not undergo device implantation but received usual care. NYHA class and 6-minute walk testing were assessed at baseline and 90 days. All hospitalizations were collected after 6 months of the implantation date (average follow-up, 15 months) and compared with the number of hospitalizations experienced prior to hemodynamic monitoring.

RESULTS

Patients in both groups had similar distributions of age, sex, and ejection fraction. After 90 days, 61.8% of the monitored patients had NYHA class improvement of ≥1, compared with 12.5% in the controls (P < 0.001). Distance walked in 6 minutes increased by 54.5 meters in the monitored group (253.0 ± 25.6 meters to 307.4 ± 26.3 meters; P < 0.005), whereas no change was seen in the usual-care group. After implantation, 19.4% of the monitored group had ≥1 HF hospitalization, compared with 100% who had been hospitalized in the year prior to implantation. The monitored group had a significantly lower HF hospitalization rate (0.16; 95% confidence interval: 0.06-0.35 hospitalizations/patient-year) compared with the year prior (1.0 hospitalizations/patient-year; P < 0.001).

CONCLUSIONS

Hemodynamic-guided HF management leads to significant improvements in NYHA class and HF hospitalization rate in a real-world setting compared with usual care delivered in a comprehensive disease-management program.

Pulmonary Pressure Monitoring for Patients With Heart Failure

Heart failure (HF) affects over 5.8 million patients in the United States, and can be very costly due to the number of hospitalizations and rehospitalizations during the final years of life. Due to the large number of hospitalizations for HF exacerbations, effective methods for preventing these occurrences are necessary. Improvements in the outpatient treatment of HF, aided by noninvasive and invasive home monitoring methods, can reduce the number of hospitalizations. Pulmonary pressure monitoring through the CardioMEMS system provides one method of hemodynamic assessment of patients. The efficacy of the CardioMEMS system in reducing the number of HF exacerbations has been explored in the CHAMPION trial (CardioMEMS Heart Sensor Allows Monitoring of Pressures to Improve Outcomes in NYHA Functional Class III Heart Failure Patients), which demonstrated a reduction in hospitalizations for HF exacerbations in patients whose medical management was guided by adjusting medications based on pulmonary pressures compared with clinical signs and symptoms. Retrospective analyses suggest that HF patients of certain subgroups, including those with left heart dysfunction and those with preserved left ventricular ejection fraction, could benefit from pulmonary pressure monitoring in controlling their HF. Larger studies are needed to determine whether mortality can be reduced with pulmonary pressure monitoring.

Epidemiology of Pulmonary Hypertension in Left Heart Disease

Pulmonary hypertension (PH) in the setting of left side heart disease is associated with adverse outcomes. The exact prevalence of PH in the different pathologies that affect the left ventricle, however, is difficult to access with the current literature. The lack of a standard definition of PH in older studies, the different modalities to assess pulmonary artery pressures and the varying disease severity, all account for the great variability in the reported prevalence of PH. PH can accompany heart failure (HF) with reduced (HFrEF) or preserved ejection fraction (HFpEF) as well as mitral and aortic valve disease; in any of these instances it is important to recognize whether the elevation of pulmonary pressures is driven by elevated left ventricular pressures only (isolated post-capillary PH) or if there is an accompanying remodeling component in the pulmonary arterioles (combined post-capillary and pre-capillary PH). The objective of this review is to describe the definitions, prevalence and the risk factors associated with the development of PH in the setting of HFrEF, HFpEF and valvular heart disease.

Physiological Techniques and Pulmonary Hypertension - Left Heart Disease

Group 2 Pulmonary hypertension (PH) is associated with left heart disease (LHD;Group 2 PH) and is the most common form of PH. Group 2 PH represents an important subgroup of patients with LHD where the development of PH leads to a significant increase in morbidity and mortality. Early diagnosis may provide an opportunity to intervene and significantly delay progression. In addition to clinical suspicion, several approaches including hemodynamic assessment, exercise testing, and imaging techniques play an important role in better disease characterization and management. Here, we review the role of physiologic based hemodynamic and exercise assessments of Group 2 PH patients.

Sustained efficacy of pulmonary artery pressure to guide adjustment of chronic heart failure therapy: complete follow-up results from the CHAMPION randomised trial

BACKGROUND

In the CHAMPION trial, significant reductions in admissions to hospital for heart failure were seen after 6 months of pulmonary artery pressure guided management compared with usual care. We examine the extended efficacy of this strategy over 18 months of randomised follow-up and the clinical effect of open access to pressure information for an additional 13 months in patients formerly in the control group.

METHODS

The CHAMPION trial was a prospective, parallel, single-blinded, multicentre study that enrolled participants with New York Heart Association (NYHA) Class III heart failure symptoms and a previous admission to hospital. Patients were randomly assigned (1:1) by centre in block sizes of four by a secure validated computerised randomisation system to either the treatment group, in which daily uploaded pulmonary artery pressures were used to guide medical therapy, or to the control group, in which daily uploaded pressures were not made available to investigators. Patients in the control group received all standard medical, device, and disease management strategies available. Patients then remained masked in their randomised study group until the last patient enrolled completed at least 6 months of study follow-up (randomised access period) for an average of 18 months. During the randomised access period, patients in the treatment group were managed with pulmonary artery pressure and patients in the control group had usual care only. At the conclusion of randomised access, investigators had access to pulmonary artery pressure for all patients (open access period) averaging 13 months of follow-up. The primary outcome was the rate of hospital admissions between the treatment group and control group in both the randomised access and open access periods. Analyses were by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00531661.

FINDINGS

Between Sept 6, 2007, and Oct 7, 2009, 550 patients were randomly assigned to either the treatment group (n=270) or to the control group (n=280). 347 patients (177 in the former treatment group and 170 in the former control group) completed the randomised access period in August, 2010, and transitioned to the open access period which ended April 30, 2012. Over the randomised access period, rates of admissions to hospital for heart failure were reduced in the treatment group by 33% (hazard ratio [HR] 0·67 [95% CI 0·55-0·80]; p<0·0001) compared with the control group. After pulmonary artery pressure information became available to guide therapy during open access (mean 13 months), rates of admissions to hospital for heart failure in the former control group were reduced by 48% (HR 0·52 [95% CI 0·40-0·69]; p<0·0001) compared with rates of admissions in the control group during randomised access. Eight (1%) device-related or system related complications and seven (1%) procedure-related adverse events were reported.

INTERPRETATION

Management of NYHA Class III heart failure based on home transmission of pulmonary artery pressure with an implanted pressure sensor has significant long-term benefit in lowering hospital admission rates for heart failure.

FUNDING

St Jude Medical Inc.

Recognizing Pulmonary Hypertension and Right Ventricular Dysfunction in Heart Failure

Pulmonary hypertension (PH) in the setting of left heart disease (LHD) or heart failure (HF) is the most common form of PH, yet its prevalence is underappreciated. Varying terminology possibly leads to misconceptions in pathophysiology, diagnosis and management. The accurate diagnosis of PH due to LHD is contingent upon hemodynamic assessment via right heart catheterization, however due to limitations in access, comprehensive echocardiography and integrative scoring systems are frequently used. When present in the setting of PH due to LHD, right ventricular dysfunction (RVD) confers a poor clinical prognosis. The management of RVD is directed towards treating underlying HF and/or valvular disease. Implantable hemodynamic monitors may offer opportunity to obtain longitudinal information to increase diagnostic accuracy as well as monitor the effect of treatment of PH in the setting of HF with and without the presence of RVD.

Management of pulmonary hypertension due to heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) is a major cause of HF-related morbidity and mortality, with no medical therapy proven to modify the underlying disease process and result in improvements in survival. With long-standing pulmonary venous congestion, a majority of HFpEF patients develop pulmonary hypertension (PH). Elevated pulmonary pressures have been shown to be a major determinant of mortality in this population. Given the paucity of available disease-modifying therapies for HFpEF, there has been a considerable interest in evaluating new therapeutic options specifically targeting PH in this patient population.

Limitations of right heart catheterization in the diagnosis and risk stratification of patients with pulmonary hypertension related to left heart disease: insights from a wireless pulmonary artery pressure monitoring system

BACKGROUND

Although right heart catheterization (RHC) remains the gold standard for assessment of hemodynamics in patients with known or suspected pulmonary hypertension (PH), there are significant limitations to this type of assessment. The current study evaluates the limitations of RHC in the diagnosis of left heart-related PH (World Health Organization group II) among patients enrolled in the CHAMPION trial and discusses insights into patient risk from home implantable hemodynamic monitor (IHM) data that were not identified at the time of the RHC procedure.

METHODS

The CHAMPION trial enrolled 550 New York Heart Association functional class III patients who had been hospitalized for heart failure (HF) in the previous year, regardless of left ventricular ejection fraction or etiology. Hemodynamic data obtained during baseline RHC were compared with IHM data obtained during the first week of home readings. HF hospitalization rates and mortality were analyzed to assess patient risk.

RESULTS

The study population for this retrospective analysis comprised 537 patients with available IHM data. For 320 patients in the PHRHC group, home IHM data confirmed the RHC findings with similar mean pulmonary artery pressures obtained from both methods (36 mm Hg vs 36 mm Hg, p = 0.5066). However, of the 217 patients in the No PHRHC group, 106 patients (48.8%) exhibited PH based on the home IHM data (PHIHM group). The remaining 111 patients (51.2%) in the No PHRHC group had no evidence of PH on the IHM data (No PHIHM group). Patients in the No PHRHC/PHIHM group had significantly higher mean PA pressures on IHM than patients in the No PHRHC/No PHIHM group (31 mm Hg vs 18 mm Hg, p < 0.0001). Patients in the No PHRHC/No PHIHM group had significantly lower HF hospitalization rates than patients in the No PHRHC/PHIHM group (0.25 vs 0.49, incidence rate ratio = 0.51, 95% confidence interval = 0.33-0.77, p = 0.0007).

CONCLUSIONS

Using only RHC, World Health Organization group II PH may be significantly under-diagnosed. In patients with left-sided HF and resting mean PA pressure ≤25 mm Hg during RHC, more frequent PA pressure monitoring using an IHM device can provide additional data for improved diagnosis and patient risk stratification compared with a single RHC alone.