Percutaneous left ventricular partitioning in patients with chronic heart failure and a prior anterior myocardial infarction: Results of the PercutAneous Ventricular RestorAtion in Chronic Heart failUre PaTiEnts Trial

OBJECTIVES

The aim of this study was to assess the feasibility, safety, and preliminary efficacy of a novel percutaneous left ventricular partitioning device (VPD) in patients with chronic heart failure (HF) and a prior anterior myocardial infarction.

BACKGROUND

Anterior myocardial infarction is frequently followed by left ventricular remodeling, HF, and increased long-term morbidity and mortality.

METHODS

Thirty-nine patients were enrolled in a multinational, nonrandomized, longitudinal investigation. The primary end point was an assessment of safety, defined as the successful delivery and deployment of the VPD and absence of device-related major adverse cardiac events over 6 months. Secondary (exploratory) efficacy end points included changes in hemodynamics and functional status and were assessed serially throughout the study.

RESULTS

Ventricular partitioning device placement was not attempted in 5 (13%) of 39 subjects. The device was safely and successfully implanted in 31 (91%) of the remaining 34 patients or 79% of all enrolled patients. The 6-month rate of device-related major adverse cardiac event occurred in 5 (13%) of 39 enrolled subjects and 5 (15%) of 34 treated subjects, with 1 additional event occurring between 6 and 12 months. For patients discharged with the device to 12 months (n = 28), New York Heart Association class (2.5 ± 0.6 to 1.3 ± 0.6, P < .001) and quality-of-life scores (38.6 ± 6.1 to 28.4 ± 4.4, P < .002) improved significantly; however, the 6-minute hall walk distance (358.5 ± 20.4 m to 374.7 ± 25.6 m, P nonsignificant) only trended toward improvement.

CONCLUSIONS

The left VPD appears to be relatively safe and potentially effective in the treatment for patients with HF and a prior anterior myocardial infarction. However, these limited results suggest the need for further evaluation in a larger randomized controlled trial.

The efficacy and safety of lixivaptan in outpatients with heart failure and volume overload: results of a multicentre, randomized, double-blind, placebo-controlled, parallel-group study

AIMS

Volume overload is the dominant feature of decompensated heart failure (HF) and it often results in adverse clinical outcomes. Vasopressin receptor antagonists such as lixivaptan may provide effective volume unloading. This study assessed weight loss after 1 day and 8 weeks of treatment with lixivaptan in outpatients with HF and volume overload.

METHODS AND RESULTS

This phase II, 8-week, multicentre, double-blind, parallel-group study randomized participants (2:1) to receive lixivaptan 100 mg or placebo once daily (in addition to standard HF therapy). Body weight and cardiovascular assessments were made at baseline, Day 1 (not cardiovascular), Weeks 1, 2, 4, and 8, and 7 days post-treatment. The Trail-making Test, part B (TMT-B) and the Medical Outcomes Survey 6-item cognitive function scale (MOS-6) were assessed at baseline and Week 4. The study randomized 170 participants (lixivaptan, n = 111; placebo, n = 59). Most (97.1%) were receiving pharmacological therapy for HF at baseline. Demographic characteristics were generally similar between the two groups. Body weight decreased significantly from baseline to Day 1 with lixivaptan vs. placebo (least-square mean change ± standard error: - 0.38 ± 0.08 kg vs. +0.13 ± 0.11 kg; P < 0.001) and at Weeks 1, 2, and 4 (P < 0.01). Cardiovascular changes were generally similar in both groups, though orthopnoea and dyspnoea improved in the lixivaptan group vs. placebo. The TMT-B and MOS-6 showed no significant differences between groups. Lixivaptan was well tolerated-thirst and polyuria occurred more frequently vs. placebo.

CONCLUSIONS

In outpatients with HF and volume overload, lixivaptan 100 mg once daily, when added to standard therapy, reduced body weight, improved dyspnoea and orthopnoea, and was well tolerated.

TRIAL REGISTRATION

NCT01055912.

Transvenous Phrenic Nerve Stimulation—A Novel Therapy for Central Sleep Apnea in Heart Failure

Central sleep apnea (CSA) is a prominent co-morbidity in heart failure (HF) resulting from dysregulated neurological responses to abnormal carbon dioxide levels. The presence of CSA in HF has been linked with deleterious physiological changes and is associated with increased mortality, yet treatment options for CSA in HF are currently lacking. This article briefly reviews the mechanisms of CSA in HF as well as the available evidence on present therapies, and describes phrenic nerve stimulation as a potential novel therapeutic approach.

Sites of left and right ventricular lead implantation and response to cardiac resynchronization therapy observations from the REVERSE trial

OBJECTIVES

The objective of this study is to ascertain the effects of the left (LV) and right (RV) ventricular lead tip position in response to cardiac resynchronization therapy (CRT).

BACKGROUND

The REVERSE randomized trial examined the effects of CRT in patients with asymptomatic or mildly symptomatic heart failure (HF).

METHODS

We analysed data collected from the active group (CRT-ON) of REVERSE in whom the precise locations of the LV and RV ventricular lead tips were determined from postoperative chest roentgenograms as part of a prespecified sub-study. LV position was classified as lateral or non-lateral, and apical or non-apical. RV position was classified as apical or non-apical. Echocardiographic LV end-systolic volume index (LVESVi), QRS duration, and clinical outcomes at 12-24 months of follow-up were evaluated with respect to the lead tip position. The primary trial endpoint was the proportion of patients with a worsened HF clinical composite response, scored as improved, unchanged, or worsened.

RESULTS

Totally 346 patients included in this analysis were followed for a median of 12.6 months (interquartile range: 11.9-23.9 months). The proportion of worsened HF clinical composite response did not correlate with lead position, whereas a significantly greater decrease in the powered secondary endpoint of LVESVi was observed with the non-apical vs. the apical LV lead positions. CRT-paced QRS duration was significantly shorter than at baseline in patients with lateral vs. non-lateral LV position, as well non-apical vs. apical LV position. The incidence of composite endpoint of death and first hospitalization for HF was lower in the LV lateral than in the non-lateral (HR 0.44; 95% CI 0.19-0.99; P= 0.04), and in the LV non-apical than in the apical group (HR 0.27; 95% CI 0.11-0.63; P= 0.001). No significant differences were observed between RV apical and non-apical positions of the lead tip.

CONCLUSIONS

A more favourable outcome of CRT with regard to LV reverse remodelling and the composite of time to death or first HF hospitalization was observed when the LV lead tip was implanted in the lateral wall, away from the apex, while the position of the RV lead tip was indifferent. The long-term change in QRS duration was significantly associated with the position of the LV lead tip. ClinicalTrials.gov Identifier: NCT00271154.

Transvenous Phrenic Nerve Stimulation – A Novel Therapy for Central Sleep Apnoea in Heart Failure

Central sleep apnoea (CSA) is a prominent co-morbidity in heart failure (HF) resulting from dysregulated neurological responses to abnormal carbon dioxide levels. The presence of CSA in HF has been linked with deleterious physiological changes and is associated with increased mortality, yet treatment options for CSA in HF are currently lacking. This article briefly reviews the mechanisms of CSA in HF as well as the available evidence on present therapies, and describes phrenic nerve stimulation as a potential novel therapeutic approach.

CHAMPION trial rationale and design: the long-term safety and clinical efficacy of a wireless pulmonary artery pressure monitoring system

BACKGROUND

Decompensated heart failure (HF) is associated with unacceptable morbidity and mortality risks. Recent implantable technology advancements allow frequent filling pressure monitoring and provide insight into HF pathophysiology and a new tool for HF management.

METHODS

The CHAMPION trial is a prospective, multicenter, randomized, single-blind clinical trial testing the hypothesis that HF management guided by frequently assessed pulmonary artery pressures is superior to traditional methods. A total of 550 subjects with New York Heart Association (NYHA) functional class III HF were enrolled at 64 sites in the United States. All subjects received the CardioMEMS HF sensor as a permanent pulmonary artery implant and were randomized to the treatment or the control group before discharge. The treatment group received traditional HF management guided by hemodynamic information from the sensor. The control group received traditional HF disease management. Safety endpoints include freedom from device/system-related complications and freedom from HF sensor failure at 6 months. The efficacy endpoint is a reduction in the rate of HF-related hospitalizations in the treatment group versus the control group at 6 months.

CONCLUSIONS

The CHAMPION trial will investigate the safety and clinical efficacy of the CardioMEMS hemodynamic monitoring system and may establish this management strategy as a new paradigm for the medical management of patients with symptomatic HF.

Telemedicine and remote management of patients with heart failure

Advances in telecommunication technologies have created new opportunities to provide telemedical care as an adjunct to medical management of patients with heart failure. Meta-analyses suggest that telemedicine can reduce morbidity and mortality in such patients; however, two prospective clinical trials not included in the analyses do not support these findings. Therefore, the effectiveness of telemedicine in heart failure is not established. Telemedicine approaches range from computer-based support systems to programmes led by nurses and physicians. Standardisation and appropriate classification of telemedical systems are needed to enable accurate interpretation of clinical trials. Here we propose a classification of four generations of telemedicine in heart failure. Not all approaches are the same and not every patient with heart failure will need telemedicine. Crisis prevention and treatment, and stabilisation and self-empowerment of patients are focuses of telemedicine in heart failure. The profile of patients who can potentially benefit from telemedicine is unknown and should be investigated in adequately powered randomised clinical trials. We are optimistic that telemedicine is an efficient approach and will become an important feature of management in heart failure.

Transvenous phrenic nerve stimulation for the treatment of central sleep apnoea in heart failure

AIMS

Periodic breathing with central sleep apnoea (CSA) is common in heart failure patients and is associated with poor quality of life and increased risk of morbidity and mortality. We conducted a prospective, non-randomized, acute study to determine the feasibility of using unilateral transvenous phrenic nerve stimulation for the treatment of CSA in heart failure patients.

METHODS AND RESULTS

Thirty-one patients from six centres underwent attempted transvenous lead placement. Of these, 16 qualified to undergo two successive nights of polysomnography-one night with and one night without phrenic nerve stimulation. Comparisons were made between the two nights using the following indices: apnoea-hypopnoea index (AHI), central apnoea index (CAI), obstructive apnoea index (OAI), hypopnoea index, arousal index, and 4% oxygen desaturation index (ODI4%). Patients underwent phrenic nerve stimulation from either the right brachiocephalic vein (n = 8) or the left brachiocephalic or pericardiophrenic vein (n = 8). Therapy period was (mean ± SD) 251 ± 71 min. Stimulation resulted in significant improvement in the AHI [median (inter-quartile range); 45 (39-59) vs. 23 (12-27) events/h, P = 0.002], CAI [27 (11-38) vs. 1 (0-5) events/h, P≤ 0.001], arousal index [32 (20-42) vs. 12 (9-27) events/h, P = 0.001], and ODI4% [31 (22-36) vs. 14 (7-20) events/h, P = 0.002]. No significant changes occurred in the OAI or hypopnoea index. Two adverse events occurred (lead thrombus and episode of ventricular tachycardia), though neither was directly related to phrenic nerve stimulation therapy.

CONCLUSION

Unilateral transvenous phrenic nerve stimulation significantly reduces episodes of CSA and restores a more natural breathing pattern in patients with heart failure. This approach may represent a novel therapy for CSA and warrants further study.

Device therapy in advanced heart failure: what to put in and what to turn off: remote telemonitoring and implantable hemodynamic devices for advanced heart failure monitoring in the ambulatory setting and the evolving role of cardiac resynchronization therapy

Despite evidence based medical and pharmacologic advances the management of heart failure remains challenging, especially in the ambulatory setting. There is an urgent need to develop strategies to reduce hospitalizations and re-admission rates for heart failure in general. This focused review illustrates the potential role for remote telemonitoring and implantable hemodynamic devices to address this significant issue. We also explore the growth of cardiac resynchronization therapy and how it has evolved into another tool in our armamentarium for hemodynamic monitoring.

Rationale and design of the treatment of hyponatremia based on lixivaptan in NYHA class III/IV cardiac patient evaluation (THE BALANCE) study

Hyponatremia is a common electrolyte disorder in patients with heart failure (HF) associated with cognitive dysfunction and increased mortality and rehospitalization rates. Loop diuretics worsen renal function, produce neurohormonal activation, and induce electrolyte imbalances. Lixivaptan is a selective, oral vasopressin V(2) -receptor antagonist that improves hyponatremia by promoting electrolyte-free aquaresis without significant side effects. The Treatment of Hyponatremia Based on Lixivaptan in NYHA Class III/IV Cardiac Patient Evaluation (BALANCE) study is a randomized, double-blind, placebo-controlled, phase 3 trial designed to evaluate the effects of lixivaptan on serum sodium in patients hospitalized with worsening heart failure (target N= 650), signs of congestion and serum sodium concentrations <135 mEq/L. Other endpoints include assessment of dyspnea, body weight, cognitive function, and days of hospital-free survival. Patients are randomized 1:1 to lixivaptan or matching placebo for 60 days, with a 30-day safety follow-up. Doses of lixivaptan or placebo are adjusted based on serum sodium and volume status. Lixivaptan was shown to increase serum sodium and reduce body weight, without renal dysfunction or hypokalemia. BALANCE seeks to address unmet questions regarding the use of vasopressin antagonists including their effects on cognitive function and clinical outcomes in patients with hyponatremia and worsening heart failure.

Treatment of anemia with darbepoetin alfa in heart failure

Anemia is common in heart failure (HF) patients. A prespecified pooled analysis of 2 randomized, double-blind, placebo-controlled studies evaluated darbepoetin alfa (DA) in 475 anemic patients with HF (hemoglobin [Hb], 9.0-12.5 g/dL). DA was administered subcutaneously every 2 weeks and titrated to achieve and maintain a target Hb level of 14.0+/-1.0 g/dL. By week 27, mean (SD) Hb concentrations did not increase with placebo but increased with DA from 11.5 (0.7) to 13.3 (1.3) g/dL. Hazard ratios (HRs) for DA compared with placebo for all-cause death or first HF hospitalization (composite end point), all-cause death, and HF hospitalization by month 12 were 0.67 (95% confidence interval [CI], 0.44-1.03; P=.067), 0.76 (95% CI, 0.39-1.48; P=.419), and 0.66 (95% CI, 0.40-1.07; P=.093), respectively. Incidence of adverse events was similar in both groups. In post hoc analyses, improvement in the composite end point was significantly associated with the mean Hb change from baseline (adjusted HR, 0.40; P=.017) with DA treatment. There was no increased risk of all-cause mortality or first HF hospitalization with DA in patients with reduced renal function or elevated baseline B-type natriuretic peptide, a biomarker of worse HF. These results suggest that DA is well tolerated, corrects HF-associated anemia, and may have favorable effects on clinical outcomes.

Coronary-artery bypass surgery in patients with left ventricular dysfunction

BACKGROUND

The role of coronary-artery bypass grafting (CABG) in the treatment of patients with coronary artery disease and heart failure has not been clearly established.

METHODS

Between July 2002 and May 2007, a total of 1212 patients with an ejection fraction of 35% or less and coronary artery disease amenable to CABG were randomly assigned to medical therapy alone (602 patients) or medical therapy plus CABG (610 patients). The primary outcome was the rate of death from any cause. Major secondary outcomes included the rates of death from cardiovascular causes and of death from any cause or hospitalization for cardiovascular causes.

RESULTS

The primary outcome occurred in 244 patients (41%) in the medical-therapy group and 218 (36%) in the CABG group (hazard ratio with CABG, 0.86; 95% confidence interval [CI], 0.72 to 1.04; P=0.12). A total of 201 patients (33%) in the medical-therapy group and 168 (28%) in the CABG group died from an adjudicated cardiovascular cause (hazard ratio with CABG, 0.81; 95% CI, 0.66 to 1.00; P=0.05). Death from any cause or hospitalization for cardiovascular causes occurred in 411 patients (68%) in the medical-therapy group and 351 (58%) in the CABG group (hazard ratio with CABG, 0.74; 95% CI, 0.64 to 0.85; P<0.001). By the end of the follow-up period (median, 56 months), 100 patients in the medical-therapy group (17%) underwent CABG, and 555 patients in the CABG group (91%) underwent CABG.

CONCLUSIONS

In this randomized trial, there was no significant difference between medical therapy alone and medical therapy plus CABG with respect to the primary end point of death from any cause. Patients assigned to CABG, as compared with those assigned to medical therapy alone, had lower rates of death from cardiovascular causes and of death from any cause or hospitalization for cardiovascular causes. (Funded by the National Heart, Lung, and Blood Institute and Abbott Laboratories; STICH ClinicalTrials.gov number, NCT00023595.).

Improved algorithm to detect fluid accumulation via intrathoracic impedance monitoring in heart failure patients with implantable devices

BACKGROUND

Intrathoracic impedance fluid monitoring has been shown to predict worsening congestive heart failure (CHF) in patients with implantable devices. We developed and externally validated a modified algorithm to identify worsening heart failure (HF) by using intrathoracic impedance.

METHODS AND RESULTS

The modified algorithm was developed by using published data from 81 CHF subjects averaging 259 days of follow-up. Device-measured daily impedance was input to both the existing and the modified intrathoracic impedance fluid monitoring algorithms to determine a reference impedance and a fluid index (FI). Separate validation sets included 326 cardiac resynchronization therapy device (CRT-D) patients with an average 333 days of follow-up (group 1) and 104 CRT-D/implantable cardioverter/defibrillator (ICD) patients followed for an average of 520 days (group 2). Clinicians and patients in group 2 were blinded to impedance and FI data. HF events included adjudicated HF hospitalizations or emergency room visits. Sensitivity was defined as the percentage of HF events preceded by FI exceeding the predefined threshold (60 Ω-d) within the last 2 weeks. Unexplained detections were FI threshold crossing events not followed by a HF event within 2 weeks. The modified algorithm significantly decreased unexplained detections by 30% (P = .01; GEE) in the development set, 30% (P < .001) in the group 1 validation set, and 43% (P < .001) in group 2. Sensitivity did not change significantly in any group. Simulated monthly review of FI threshold crossings identified subjects at significantly greater risk of worsening HF within the next 30 days.

CONCLUSIONS

A modified intrathoracic impedance based fluid detection algorithm lowered the number of unexplained FI threshold crossings and identified patients at significantly increased immediate risk of worsening HF.

Wireless pulmonary artery haemodynamic monitoring in chronic heart failure: a randomised controlled trial

BACKGROUND

Results of previous studies support the hypothesis that implantable haemodynamic monitoring systems might reduce rates of hospitalisation in patients with heart failure. We undertook a single-blind trial to assess this approach.

METHODS

Patients with New York Heart Association (NYHA) class III heart failure, irrespective of the left ventricular ejection fraction, and a previous hospital admission for heart failure were enrolled in 64 centres in the USA. They were randomly assigned by use of a centralised electronic system to management with a wireless implantable haemodynamic monitoring (W-IHM) system (treatment group) or to a control group for at least 6 months. Only patients were masked to their assignment group. In the treatment group, clinicians used daily measurement of pulmonary artery pressures in addition to standard of care versus standard of care alone in the control group. The primary efficacy endpoint was the rate of heart-failure-related hospitalisations at 6 months. The safety endpoints assessed at 6 months were freedom from device-related or system-related complications (DSRC) and freedom from pressure-sensor failures. All analyses were by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00531661.

FINDINGS

In 6 months, 83 heart-failure-related hospitalisations were reported in the treatment group (n=270) compared with 120 in the control group (n=280; rate 0·31 vs 0·44, hazard ratio [HR] 0·70, 95% CI 0·60-0·84, p<0·0001). During the entire follow-up (mean 15 months [SD 7]), the treatment group had a 39% reduction in heart-failure-related hospitalisation compared with the control group (153 vs 253, HR 0·64, 95% CI 0·55-0·75; p<0·0001). Eight patients had DSRC and overall freedom from DSRC was 98·6% (97·3-99·4) compared with a prespecified performance criterion of 80% (p<0·0001); and overall freedom from pressure-sensor failures was 100% (99·3-100·0).

INTERPRETATION

Our results are consistent with, and extend, previous findings by definitively showing a significant and large reduction in hospitalisation for patients with NYHA class III heart failure who were managed with a wireless implantable haemodynamic monitoring system. The addition of information about pulmonary artery pressure to clinical signs and symptoms allows for improved heart failure management.

FUNDING

CardioMEMS.