Heart failure · Narrow QRS
CCM: a device option
when CRT isn't.
Most heart failure patients have a narrow QRS, so CRT cannot help them. Cardiac contractility modulation sends non-pacing electrical signals to the heart muscle during each beat to strengthen contraction. It is approved in China and aims to improve symptoms and exercise capacity.
Quick answer
What is cardiac contractility modulation (CCM)?
CCM is an implanted device (the Optimizer) that delivers non-excitatory electrical signals to the heart during the absolute refractory period, when they cannot trigger a beat, to strengthen contraction. It is intended for patients with NYHA class III symptoms, an ejection fraction of 25–45% and a QRS that is too narrow for CRT. In the FIX-HF-5C randomised trial, CCM improved peak oxygen uptake, quality of life, NYHA class and walking distance compared with medication alone.
+0.84
Peak VO₂ (ml/kg/min)
CCM vs control at 24 weeks — primary endpoint met
FIX-HF-5C, JACC HF 2018
10.8% → 2.9%
CV death or HF hospitalisation
Control vs CCM (P=0.048), secondary endpoint
FIX-HF-5C, JACC HF 2018
160
Patients randomised
NYHA III–IV, QRS < 130 ms, EF 25–45%
FIX-HF-5C, JACC HF 2018
7
Device-related events
Lower bound 80% event-free; safety goal (70%) met
FIX-HF-5C, JACC HF 2018
2021
NMPA market approval
Optimizer CCM devices, February 2021
Impulse Dynamics
Oct 2019
First implant in China
Boao Super Hospital, Hainan
Impulse Dynamics
Where CCM fits
CCM compared with the other devices.
CRT
Fixes electrical dyssynchrony. Best with LBBB and QRS ≥150 ms; not recommended below 130 ms (ESC).
Different patients
CCM
Strengthens contraction without changing the rhythm. For NYHA III, EF 25–45%, patients who are not CRT candidates.
Symptoms + exercise
ICD
CCM does not protect against sudden death. A patient with EF ≤35% may need an ICD as well, as a separate device.
Can coexist
The evidence
What FIX-HF-5C showed — and its limits
FIX-HF-5C randomised 160 patients with NYHA class III–IV symptoms, QRS under 130 ms and ejection fraction of 25–45%. It compared continued medical therapy (86) with CCM (74) for 24 weeks. The primary endpoint, peak oxygen uptake on exercise testing, improved by 0.84 ml/kg/min with CCM. The Minnesota quality-of-life score, NYHA class and 6-minute walk distance were also better.
The trial was unblinded and relatively small, and its primary analysis borrowed 30% of its data from a subgroup of the earlier FIX-HF-5 study. The drop in cardiovascular death or heart failure hospitalisation (10.8% to 2.9%) was a secondary result. CCM is best understood as a treatment for symptoms and exercise capacity, not a proven way to extend life.
| Item | Result |
|---|---|
| Population | NYHA III–IV, QRS < 130 ms, EF 25–45%; 160 randomised (86 control, 74 CCM) |
| Primary endpoint | Peak VO₂ +0.84 ml/kg/min (95% Bayesian credible interval 0.123–1.552) |
| Secondary | Quality of life (P<0.001), NYHA class (P<0.001), 6-minute walk (P=0.02) all better |
| Safety | 7 device-related events; lower bound 80% event-free (goal ≥70%) |
| CV death / HF hospitalisation | 10.8% (control) vs 2.9% (CCM), P=0.048 |
In China
Approval and availability
The manufacturer, Impulse Dynamics, reports that China's regulator first approved the Optimizer system in December 2017 and granted market authorisation for its Optimizer CCM devices in February 2021. The first Optimizer Smart in China was implanted on 29 October 2019 at Boao Super Hospital in Hainan's Lecheng medical pilot zone, by Professor Hua Wei. CCM is offered at a limited number of centres, so availability should be confirmed before you travel.
Centres
Where CCM has been
implanted in China.
Boao Super Hospital 博鳌超级医院
First Optimizer Smart CCM implant in China, 29 October 2019 (manufacturer report)
Fuwai Hospital 阜外医院
National Center for Cardiovascular Diseases; arrhythmia and heart failure programme
FAQ
CCM questions — answered.
- Who is a candidate for CCM?
- Patients with NYHA class III heart failure, an ejection fraction of 25–45% and symptoms despite optimised medication, who are not candidates for CRT (usually because the QRS is narrow). These are the patients studied in FIX-HF-5C. Your cardiologist will also check rhythm, existing devices and other conditions.
- Is CCM the same as a pacemaker?
- No. A pacemaker triggers heartbeats. CCM delivers its signal when the heart muscle can't be triggered (the absolute refractory period), so it changes how strongly the muscle contracts, not when it beats.
- Does CCM help me live longer?
- That has not been proven. FIX-HF-5C showed better exercise capacity, quality of life and NYHA class. Fewer patients had cardiovascular death or heart failure hospitalisation (2.9% vs 10.8%), but that was a secondary result in a small, unblinded trial. Treat CCM as a symptom therapy.
- Can I have CCM and an ICD?
- Yes. CCM has no defibrillator function. If your ejection fraction is 35% or less and you meet ICD criteria, you may need a separate ICD. The two devices are checked together to ensure they work alongside each other.
- Is CCM available in China?
- Yes. According to the manufacturer, Optimizer CCM devices received Chinese market approval in February 2021. The first implant in China was at Boao Super Hospital in October 2019. Only some centres offer it, so we confirm availability and the implanting team before you book travel.
Related guides
Heart failure treatment (hub)
The step-by-step pathway from medication to devices, LVAD and transplant.
Read the guideICD for sudden-death prevention
Single-, dual-chamber and extravascular ICDs; who qualifies at EF ≤35%.
Read the guideCRT-P / CRT-D (biventricular pacing)
For wide QRS with left bundle branch block: trial data and criteria.
Read the guideLVAD (artificial heart pump)
HeartMate 3 and Chinese-made pumps: outcomes and approvals.
Read the guideHeart transplant in China
Outcomes, volumes — and the rules for foreign patients.
Read the guideCardiac surgery in China
Bypass, valve surgery, TAVR and other procedures that treat reversible causes.
Read the guideSources
References
- Abraham WT, et al. A randomized controlled trial to evaluate the safety and efficacy of cardiac contractility modulation (FIX-HF-5C). JACC Heart Fail. 2018;6(10):874–883.
- Impulse Dynamics. Impulse Dynamics receives approval to sell Optimizer CCM devices in China (press release, 22 Feb 2021); First Optimizer Smart device implanted in China — Boao Super Hospital, 29 Oct 2019.
- McDonagh TA, et al. 2021 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure. Eur Heart J. 2021;42(36):3599–3726.
- Glikson M, et al. 2021 ESC Guidelines on cardiac pacing and cardiac resynchronization therapy. Eur Heart J. 2021;42(35):3427–3520.
Narrow QRS and still breathless?
Ask whether CCM fits.
Send your echo, ECG and medication list. A partner cardiologist will tell you whether you meet the CCM criteria and which centre can do the implant. If optimising your medication should come first, the review will say so.
This page is for general education only and is not medical advice. Device and surgical treatment for heart failure depends on your ejection fraction, ECG, symptoms, other conditions and how you respond to medication, and only your cardiologist can decide what fits. Trial results describe groups of patients, not what will happen to you. We are an independent patient-coordination service and are not affiliated with any device manufacturer.