HF Etiology and cardiac contractility modulation therapy

OBJECTIVES

Our study aimed to assess the safety and efficacy of cardiac contractility modulation (CCM) therapy in patients with heart failure with reduced ejection fraction (HFrEF) depending on HF etiology.

METHODS

We enrolled 166 patients with optimal medical therapy-resistant HFrEF (median age 59 years, 83.7% males, median NYHA class - 2, median left ventricular ejection fraction (LVEF) - 29.0%) who underwent CCM therapy device implantation from 2013 to 2019 in four medical centers in Russia. The HF etiology was determined based on invasive coronary angiography or cardiac MRI data. Transthoracic echocardiography (TTE), 6-minute walking test (6MWT), and NTproBNP-tests were performed at a baseline and 12 months after the implantation.

RESULTS

The ischemic etiology of HF was revealed in 100 patients (61.5%) (ICM group); the non-ischemic group (NICM) evolved 66 patients (38.5%). Patients in the ICM group were significantly older (61[57-69] vs. 55 [42.8-61], p < 0.001), more frequently had hypertension (79% vs. 42.4%, p < 0.001) and chronic kidney disease (43% vs. 22.7%, p = 0.012). Patients in the NICM group had significantly more often atrial fibrillation (AF) (58% vs. 74%, p = 0.048), larger end-diastolic volume (EDV) (249 [208-309] vs. 220 [192-271], p = 0.019) and end-systolic volume (ESV) (183 [147-230] vs. 154 [128-199], p = 0.003). There were no significant differences in mortality between ICM and NICM groups (14.4 vs. 10.8%, p = 0.51). In 12 months, there was a significant increase in LVEF in the NICM group (+ 2.0 [2-6] vs. +7.7 [2-12], p < 0.001), while the improvement in the 6MWT (+ 75 [22-108] vs. +80 [10-160], p = 0.851) and NYHA class did not reach the level of significance. The subanalysis between patients with improved NYHA class and those without improvement revealed that patients without improvement more frequently had AF (56% vs. 89%; p < 0.01), chronic obstructive lung disease (18% vs. 35% p = 0.047), higher blood pressure (110 [105-120] vs. 120[110-129]; p = 0.032).

CONCLUSION

In this multicenter retrospective study, patients with non-ischemic HFrEF showed a significantly higher improvement in LVEF and LV reverse remodeling following CCM therapy device implantation. There was no significant association between HF etiology and survival in drug-resistant HFrEF patients following CCM therapy.

Cardiac contractility modulation in patients with heart failure - A review of the literature

Experimental in vivo and in vitro studies showed that electric currents applied during the absolute refractory period can modulate cardiac contractility. In preclinical studies, cardiac contractility modulation (CCM) was found to improve calcium handling, reverse the foetal myocyte gene programming associated with heart failure (HF), and facilitate reverse remodeling. Randomized control trials and observational studies have provided evidence about the safety and efficacy of CCM in patients with HF. Clinically, CCM therapy is indicated to improve the 6-min hall walk, quality of life, and functional status of HF patients who remain symptomatic despite guideline-directed medical treatment without an indication for cardiac resynchronization therapy (CRT) and have a left ventricular ejection fraction (LVEF) ranging from 25 to 45%. Although there are promising results about the role of CCM in HF patients with preserved LVEF (HFpEF), further studies are needed to elucidate the role of CCM therapy in this population. Late gadolinium enhancement (LGE) assessment before CCM implantation has been proposed for guiding the lead placement. Furthermore, the optimal duration of CCM application needs further investigation. This review aims to present the existing evidence regarding the role of CCM therapy in HF patients and identify gaps and challenges that require further studies.

Device therapy for patients with atrial fibrillation and heart failure with preserved ejection fraction

Device therapy is a nonpharmacological approach that presents a crucial advancement for managing patients with atrial fibrillation (AF) and heart failure with preserved ejection fraction (HFpEF). This review investigated the impact of device-based interventions and emphasized their potential for optimizing treatment for this complex patient demographic. Cardiac resynchronization therapy, augmented by atrioventricular node ablation with His-bundle pacing or left bundle-branch pacing, is effective for enhancing cardiac function and establishing atrioventricular synchrony. Cardiac contractility modulation and vagus nerve stimulation represent novel strategies for increasing myocardial contractility and adjusting the autonomic balance. Left ventricular expanders have demonstrated short-term benefits in HFpEF patients but require more investigation for long-term effectiveness and safety, especially in patients with AF. Research gaps regarding complications arising from left ventricular expander implantation need to be addressed. Device-based therapies for heart valve diseases, such as transcatheter aortic valve replacement and transcatheter edge-to-edge repair, show promise for patients with AF and HFpEF, particularly those with mitral or tricuspid regurgitation. Clinical evaluations show that these device therapies lessen AF occurrence, improve exercise tolerance, and boost left ventricular diastolic function. However, additional studies are required to perfect patient selection criteria and ascertain the long-term effectiveness and safety of these interventions. Our review underscores the significant potential of device therapy for improving the outcomes and quality of life for patients with AF and HFpEF.

Cardiac Contractility Modulation: Implications in Heart Failure, a Current Review

Cardiac contractility modulation (CCM) is a novel therapeutic approach for heart failure patients, which utilizes nonexcitatory electrical myocardial stimulation in the absolute refractory period of the cardiac cycle. This stimulation has been shown to increase contractility, leading to improved heart failure symptoms, functional status, and quality of life. CCM is FDA approved for heart failure patients with an LVEF between 25% and 45% who remained symptomatic despite optimal medical therapy and not candidate of cardiac resynchronization therapy. CCM offers expanded treatment options for heart failure patients who have continued symptoms while on optimal medical therapy.

One-Year Outcome of Cardiac Contractility Modulation in Patients With Reduced Ejection Fraction, Atrial Fibrillation, and Previous Resynchronization: A Pilot Study

BACKGROUND

After 6 months of therapy, cardiac contractility modulation (CCM) has been shown to improve symptoms, exercise tolerance, and quality of life as well as reduce the rate of hospitalizations in patients with heart failure with reduced left ventricular ejection fraction (HFrEF), but long-term effects data are lacking, with no randomized trial to date.

STUDY QUESTION

What is the long-term benefit of the CCM device implantation in symptomatic patients with severe, optimally treated HFrEF?

STUDY DESIGN

We conducted a prospective trial involving patients with symptomatic HFrEF [New York Heart Association (NYHA) Class III or IV, left ventricular ejection fraction (LVEF) ≤35%] who were supported by a CCM device.

RESULTS

Twenty patients (19 men), aged 66.5 ± 6.9 years, were provided with CCM therapy and followed up for an average duration of 321.7 ± 113.5 days. The etiology of heart failure was ischemic in 16 patients (80%), 9 patients (45%) had atrial fibrillation, 6 patients (30%) had diabetes mellitus, and mean creatinine clearance value was 54.8 ± 13.0 mL/min. Eleven patients (60%) had LVEF ≤25%. Although all the patients had an implanted cardioverter-defibrillator, 6 of them (30%) also had resynchronization therapy. The pharmacological treatment has been optimized in all patients. One year after implantation, the LVEF increased from 24.68% ± 4.5 to 34.6 ± 5 ( P < 0.0001), NYHA class improved from 3.2 ± 0.5 to 1.4 ± 0.5 ( P < 0.0001), and exercise tolerance evaluated with a 6-Minute Walk Test increased (from 307.9 ± 74.1 m to 567 ± 99.5 m; P < 0.00001). These improvements were largely seen in the first 6 months.

CONCLUSIONS

Over the course of a year, CCM therapy was associated with improved LVEF and NYHA class, as well as significantly better exercise tolerance, even in patients with atrial fibrillation and cardiac resynchronization therapy and did not seem to be associated with additional significant device-related problems.

SV, Saidova MA, Zhirov IV, Tereshchenko SN. Myocardial remodeling in patients with chronic heart failure and implanted cardiac contractility modulators

Aim. To study the effect of cardiac contractility modulation on reverse remodeling and myocardial function in patients with chronic heart failure (HF) according to echocardiography (EchoCG). Materials and methods. In a group of 40 patients with a combination of chronic HF and atrial fibrillation (AF), the dynamics of standard EchoCG parameters and the effectiveness of myocardial work of the left ventricle (LV) against the background of 12-month therapy of cardiac contractility modulation (CCM) were analyzed. Results. The results obtained indicate a statistically significant positive effect of CCM on LV remodeling parameters and the effectiveness of myocardial work according to EchoCG. Conclusion. Transthoracic echocardiography is the main imaging method and provides great opportunities for evaluating the effectiveness of HF treatment, including non-drug methods such as CCM. Evaluation of LV myocardial function in patients with HF and implanted CCM devices is a promising scientific and practical research method.

Emerging Implantable Device Technology for Patients at the Intersection of Electrophysiology and Heart Failure Interdisciplinary Care

Cardiac implantable electronic devices (CIEDs), including implantable cardioverter-defibrillators (ICDs) and cardiac resynchronization therapy (CRT), are part of guideline- indicated treatment for a subset of patients with heart failure with reduced ejection fraction (HFrEF). Current technological advancements in CIEDs have allowed the detection of specific patient physiologic parameters used for forecasting clinical decompensation through algorithmic, multiparameter remote monitoring. Other recent emerging technologies, including cardiac contractility modulation (CCM) and baroreflex activation therapy (BAT), may provide symptomatic or physiologic benefit in patients without an indication for CRT. Our goal in this state-of-the-art review is to describe the commercially available new technologies, purported mechanisms of action, evidence surrounding their clinical role, limitations, and future directions. Finally, we underline the need for standardized workflow and close interdisciplinary management of this population to ensure the delivery of high-quality care.

How many patients with heart failure are eligible for cardiac contractility modulation therapy?

BACKGROUND

Increasing evidence exists suggesting that cardiac contractility modulation therapy (CCM) improves symptoms in heart failure patients if various selection criteria are fulfilled. The aim of this study is to analyse an unselected sample of heart failure patients to establish what percentage of patients would meet the current criteria for CCM therapy.

METHODS

All patients admitted to two district general hospitals in the UK in 2018 with a diagnosis of heart failure were audited for eligibility for CCM therapy. The selection criteria were (a) ejection fraction (EF) 25%-45%, (b) QRS duration less than 130 ms, (c) New York Heart Association (NYHA) class 3-4 and (d) treated for heart failure for at least 90 days and on stable medications. Exclusion criteria included: (a) significant valvular disease, (b) permanent or persistent atrial fibrillation, (c) biventricular pacing system implanted or QRS duration more than 130 ms and (4) patients not suitable for device therapy as a result of palliative treatment intent.

RESULTS

A total of 475 patients were admitted with heart failure during the study period. From this group, 24 (5.1%) patients fulfilled the criteria for CCM therapy. The mean age and ejection fraction were 70.8 ± 10.2 and 32.5% ± 7.4%. The majority of patients were men (71%) and had an ischaemic cardiomyopathy (75%). If patients with atrial fibrillation were included, an additional 18 (3.8%) patients potentially may be eligible for CCM.

CONCLUSION

Only 5.1% of all patients presenting with heart failure might benefit from cardiac CCM. This is a small proportion of the overall heart failure population. However, this population has no other current option for device therapy of their condition.

Cardiac contractility modulation in left ventricular systolic dysfunction: one-year experience in a pilot study and design of a prospective registry

BACKGROUND

Cardiac contractility modulation (CCM) is a treatment option for patients suffering symptomatic chronic heart failure (CHF) with reduced left ventricular ejection fraction (LVEF) who are not eligible for cardiac resynchronization. Data on mid-term follow-up are limited to small observational studies. The aim of this study was to assess the impact of CCM on quality of life, symptoms, exercise tolerance and left ventricular function in patients with CHF and moderate-to-severe left ventricular systolic dysfunction.

METHODS

Patients suffering CHF with LVEF <45% and NYHA class >II despite optimal medical therapy, underwent CCM implantation. Enrolled patients underwent baseline and 3, 6 and 12-months evaluation with ECG, echocardiogram, clinical assessment, 6-minute walking test and Minnesota Living with Heart Failure Questionnaire (MLWHFQ).

RESULTS

Ten patients underwent CCM implantation. All patients were actively treated with the optimal pharmacological therapy as tolerated and had at least one hospitalization for worsening heart failure during the previous year. After a mean follow-up of 15 months, 9 patients were alive, while one patient died for worsening heart failure precipitated by pneumonia. Among the remaining 9 patients, LVEF improved non-significantly from 29.4±8% to 32.2±10% (P=0.092), 6-minute walking test distance improved from 179±73 m to 304±99 m (P<0.001), NYHA class reduced from 3.0±0.4 to 1.6±0.5 (P=0.003) and MLWHFQ score improved from 59.6±49 to 34.2±32 (P=0.037). Only 2 patients have been hospitalized during the 12 months. Overall, a net clinical benefit was detected in 6 out of 9 patients.

CONCLUSIONS

CCM could be effective in improving quality of life, symptoms and exercise tolerance, and reduces hospitalizations in patients with symptomatic CHF on top of optimal medical and electrical therapy. A prospective registry has been designed to identify the subsets of patients gaining more benefit, and to assess the long-term effect of CCM on those clinical endpoints.

Optimizer Smart in the treatment of moderate-to-severe chronic heart failure

Cardiac contractility modulation, also referred to as CCM™, by the Optimizer Smart device is an innovative intracardiac device-based therapy that has been recently US FDA-approved for the treatment of patients with chronic heart failure, left ventricular ejection fraction (LVEF) between 25 and 45%, QRS <130 ms who remain symptomatic despite optimal medical therapy. Clinical trials demonstrate that CCM therapy is safe and effective in reducing heart failure hospitalization and improving heart failure symptoms, quality of life and functional performance. This novel device-based therapeutic offers benefits to patients who do not otherwise qualify for cardiac resynchronization therapy. CCM expands the indication beyond the traditional LVEF cutoff of 35% to a newer group including patients who fall in midrange LVEF group, up to 45%.

Outcomes of Cardiac Contractility Modulation: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

Background

Cardiac contractility modulation (CCM) is a device therapy for systolic heart failure (HF) in patients with narrow QRS. We aimed to perform an updated meta-analysis of the randomized clinical trials (RCTs) to assess the efficacy and safety of CCM therapy.

Methods

We conducted a systematic review and meta-analysis of randomized clinical trials (RCTs) between January 2001 and June 2018. Outcomes of interest were peak oxygen consumption (peak VO2), 6-Minute Walk Distance (6MWD), Minnesota Living with Heart Failure Questionnaire (MLHFQ), HF hospitalizations, cardiac arrhythmias, pacemaker/ICD malfunctioning, all-cause hospitalizations, and mortality. Data were expressed as standardized mean difference (SMD) or odds ratio (OR).

Results

Four RCTs including 801 patients (CCM n = 394) were available for analysis. The mean age was 59.63 ± 0.84 years, mean ejection fraction was 29.14 ± 1.22%, and mean QRS duration was 106.23 ± 1.65 msec. Mean follow-up duration was six months. CCM was associated with improved MLWHFQ (SMD -0.69, p = 0.0008). There were no differences in HF hospitalizations (OR 0.76, p = 0.12), 6MWD (SMD 0.67, p = 0.10), arrhythmias (OR 1.40, p = 0.14), pacemaker/ICD malfunction/sensing defect (OR 2.23, p = 0.06), all-cause hospitalizations (OR 0.73, p = 0.33), or all-cause mortality (OR 1.04, p = 0.92) between the CCM and non-CCM groups.

Conclusions

Short-term treatment with CCM may improve MLFHQ without significant difference in 6MWD, arrhythmic events, HF hospitalizations, all-cause hospitalizations, and all-cause mortality. There is a trend towards increased pacemaker/ICD device malfunction. Larger RCTs might be needed to determine if the CCM therapy will be beneficial with longer follow-up.

New Generation Cardiac Contractility Modulation Device-Filling the Gap in Heart Failure Treatment

(1) Background: Heart failure (HF) is a major cause of morbidity and mortality throughout the world. Despite substantial progress in its prevention and treatment, mortality rates remain high. Device therapy for HF mainly includes cardiac resynchronization therapy (CRT) and the use of an implantable cardioverter-defibrillator (ICD). Recently, however, a new device therapy—cardiac contractility modulation (CCM)—became available. (2) Aim: The purpose of this study is to present a first case-series of patients with different clinical patterns of HF with a reduced ejection fraction (HFrEF), supported with the newest generation of CCM devices. (3) Methods and results: Five patients with a left ventricular ejection fraction (LVEF) ≤ 35% and a New York Heart Association (NYHA) class ≥ III were supported with CCM OPTIMIZER^® SMART IPGCCMX10 at our clinic. The patients had a median age of 67 ± 8.03 years (47–80) and were all males—four with ischemic etiology dilated cardiomyopathy. In two cases, CCM was added on top of CRT (non-responders), and, in one patient, CCM was delivered during persistent atrial fibrillation (AF). After 6 months of follow-up, the LVEF increased from 25.4 ± 6.8% to 27 ± 9%, and the six-minute walk distance increased from 310 ± 65.1 m to 466 ± 23.6 m. One patient died 47 days after device implantation. (4) Conclusion: CCM therapy provided with the new model OPTIMIZER^® SMART IPG CCMX10 is safe, feasible, and applicable to a wide range of patients with HF.

[Cardiac contractility modulation for treatment of chronic heart failure]

The worldwide prevalence of heart failure is 1-2% with a portion of >10% in patients older than 70 years. In addition to treatment of causal determined factors and lifestyle modification, basic treatment consists of guideline-directed medical therapy with angiotensin-converting enzyme inhibitors (ACE), β‑blockers (BB), mineralocorticoid receptor antagonists (MRA), diuretics, digitalis (class IIb recommendation), angiotensin receptor blockers (ARB), Iƒ-channel blockers plus recently recommended in the guidelines angiotensin receptor neprilysin inhibitor (ARNI) to substitute the ACE inhibitor (class I b). Cardiac contractility modulation (CCM) is a device-based electrical therapy for the treatment of refractory heart failure symptoms. CCM signals are relatively high intensity, nonexcitatory signals applied during the absolute refractory period that have been shown to enhance the strength of left ventricular (LV) contraction and improve exercise tolerance and quality of life. The mechanisms of action appear to involve effects on myocardial gene expression and normalization of myocardial key-proteins. So far, more than 3500 CCM devices have been implanted worldwide. For patients with symptomatic heart failure and narrow QRS complex, CCM is together with baroreceptor activation the only additive electrical therapy which had been approved in Germany. Actually, for the first time, CCM has been referenced in the current Heart Failure Guidelines. Prognostic data with regard to mortality are currently being evaluated in case series; some of which have since been published. Approval by the US Food and Drug Administration (FDA) is expected within the next months.

Long-term results of combined cardiac contractility modulation and subcutaneous defibrillator therapy in patients with heart failure and reduced ejection fraction

BACKGROUND

Cardiac contractility modulation (CCM) is an electrical-device therapy for patients with heart failure with reduced ejection fraction (HFrEF). Patients with left ventricular ejection fraction (LVEF) ≤35% also have indication for an implantable cardioverter-defibrillator (ICD), and in some cases subcutaneous ICD (S-ICD) is selected.

HYPOTHESIS

CCM and S-ICD can be combined to work efficaciously and safely.

METHODS

We report on 20 patients with HFrEF and LVEF ≤35% who received CCM and S-ICD. To exclude device interference, patients received intraoperative crosstalk testing, S-ICD testing, and bicycle exercise testing while CCM was activated. Clinical and QOL measures before CCM activation and at last follow-up were analyzed. S-ICD performance was evaluated while both CCM and S-ICD were active.

RESULTS

Mean follow-up was 34.3 months. NYHA class improved from 2.9 ± 0.4 to 2.1 ± 0.7 (P < 0.0001), Minnesota Living With Heart Failure Questionnaire score improved from 50.2 ± 23.7 to 29.6 ± 22.8 points (P < 0.0001), and LVEF improved from 24.4% ± 8.1% to 30.9% ± 9.6% (P = 0.002). Mean follow-up time with both devices active was 22 months. Three patients experienced a total of 6 episodes of sustained ventricular tachycardia, all successfully treated with first ICD shock. One case received an inappropriate shock unrelated to the concomitant CCM. One patient received an LVAD, so CCM and S-ICD were discontinued.

CONCLUSIONS

CCM and S-ICD can be successfully combined in patients with HFrEF. S-ICD and CCM remain efficacious when used together, with no interference affecting their function.

Cardiac contractility modulation: a novel approach for the treatment of heart failure

Heart failure is a major health problem worldwide and, despite effective therapies, is expected to grow by almost 50 % over the next 15 years. Five-year mortality remains high at 50 % over 5 years. Because of the economic burden and large impact on quality of life, substantial effort has focused on treatments with multiple medical (beta-blockers, angiotensin-converting enzyme inhibitors and angiotensin receptor blockers (ARB), aldosterone antagonists, and combination of ARB/neprilysin blockers, ivabradine) and device therapies (ICD, CRT) which have been implemented to reduce disease burden and mortality. However, in the past decade only two new medical therapies and no devices have been approved by the US FDA for the treatment of heart failure. This review highlights the preclinical and clinical literature, and the implantation procedure, related to a relatively new therapeutic device for heart failure; cardiac contractility modulation (CCM). CCM delivers a biphasic high-voltage bipolar signal to the RV septum during the absolute refractory period, eliciting an acute increase in global contractility, and chronically producing a sustained improvement in quality of life, exercise tolerance, and heart failure symptoms. The technology is used commercially in Europe with nearly 3000 patients implanted worldwide. Indications include patients with reduced EF and normal or slightly prolonged QRS duration, thus filling an important therapeutic gap among the 2/3 of patients with heart failure who do not meet criteria for CRT. The mechanism by which CCM provides benefit can be seen at the cellular level where improved calcium handling (phosphorylation of phospholamban, upregulation of SERCA-2A), reversal of the fetal myocyte gene program associated with heart failure, and reverse remodeling are observed. Recent retrospective studies indicate a long-term mortality benefit. A pivotal randomized controlled study is currently being completed in the USA. CCM appears to be an effective, safe technology for the treatment of heart failure with reduced ejection fraction.

Heart Failure With Reduced Ejection Fraction And A Narrow QRS Complex: Combination Of A Subcutaneous Defibrillator With Cardiac Contractility Modulation

Cardiac contractility modulation (CCM) is a relatively new electrical therapy for heart failure patients with reduced ejection fraction. The majority of patients eligible for CCM will also need an implantable cardioverter-defibrillator (ICD). To-date, three pacing electrodes are mandatory for CCM therapy because the current CCM signal delivery algorithm requires sequential intracardiac sensing of a p-wave, followed by appropriately timed ventricular activation by the two ventricular septal leads. As there is no device combining CCM with ICD functions, most CCM patients will need multiple intracardiac electrodes, which increase the cumulative risk for complications such as systemic infections, thrombosis of central venous lines, insulation failures or lead fractures. The long-term complications associated with trans-venous ICD leads have led to the development of a totally subcutaneous implantable cardioverter-defibrillator (S-ICD). In this essay the two technologies CCM and S-ICD are reviewed. Additionally, we present their successful combination on the basis of a case report on the first patient receiving both devices.

Efficacy and survival in patients with cardiac contractility modulation: long-term single center experience in 81 patients

AIMS

To analyze long-term efficacy and survival in patients with chronic heart failure treated with cardiac contractility modulation.

METHODS

81 patients implanted with a CCM device between 2004 and 2012 were included in this retrospective analysis. Changes in NYHA class, ejection fraction (EF), Minnesota Living with Heart Failure Questionnaire, NT-proBNP and peak VO₂ were analyzed during a mean follow up of 34.2 ± 28 months (6-123 months). Observed mortality rate was compared with that predicted by the MAGGIC Score.

RESULTS

Patients were 61 ± 12 years old with EF 23 ± 7%. Heart failure was due to ischemic (n=48, 59.3%) or idiopathic dilated (n=33, 40.7%) cardiomyopathy. EF increased from 23.1 ± 7.9 to 29.4 ± 8.6% (p<0.05), mean NT-proBNP decreased from 4395 ± 3818 to 2762 ± 3490 ng/l (p<0.05) and mean peak VO2 increased from 13.9 ± 3.3 to 14.6 ± 3.5 ml/kg/min (p=0.1). The overall clinical responder rate (at least 1 class improvement of NYHA within 6 months or last follow-up) was 74.1%. 21 (25.9%) patients died during follow up, 11 (52.4%) due to cardiac conditions and 10 (47.6%) due to non-cardiac conditions. Mortality rates at 1 and 3 years were 5.2% and 29.5% compared to mortality rates estimated from the MAGGIC risk score of 18.4% (p<0.001) and 40% (p=ns), respectively. Log-Rank analysis of all events through 3 years of follow-up, however, was significantly less than predicted (p=0.022).

CONCLUSIONS

CCM therapy improved quality of life, exercise capacity, NYHA class, EF and NT-proBNP levels during long-term follow up. Mortality rates appeared to be lower than estimated from the MAGGIC score.