Randomized, double blind study of non-excitatory, cardiac contractility modulation electrical impulses for symptomatic heart failure

• Published in: European heart journal Vol. 29; no. 8; pp. 1019 - 1028
• Main Authors: Borggrefe, Martin M., Lawo, Thomas, Butter, Christian, Schmidinger, Herwig, Lunati, Maurizio, Pieske, Burkert, Misier, Anand Ramdat, Curnis, Antonio, Böcker, Dirk, Remppis, Andrew, Kautzner, Joseph, Stühlinger, Markus, Leclerq, Christophe, Táborský, Miloš, Frigerio, Maria, Parides, Michael, Burkhoff, Daniel, Hindricks, Gerhard
• Format: Journal Article
• Language: English
• Published: England Oxford University Press 01.04.2008; Oxford Publishing Limited (England)
• Subjects: Algorithms; Cardiac Pacing, Artificial - methods; Cardiopulmonary stress test; Defibrillators, Implantable; Electric Countershock - methods; Epidemiologic Methods; Event-free survival; Exercise Test - methods; Exercise Tolerance - physiology; Female; Heart failure; Heart Failure - physiopathology; Heart Failure - therapy; Humans; Male; Middle Aged; Minnesota Living with Heart Failure Questionnaire; Myocardial Contraction - physiology; Oxygen Consumption - physiology; Stroke Volume - physiology; Heart failure; Cardiopulmonary stress test; Minnesota Living with Heart Failure Questionnaire; Event-free survival
• ISSN: 0195-668X; 1522-9645
• DOI: 10.1093/eurheartj/ehn020

Aims We performed a randomized, double blind, crossover study of cardiac contractility modulation (CCM) signals in heart failure patients. Methods and results One hundred and sixty-four subjects with ejection fraction (EF) < 35% and NYHA Class II (24%) or III (76%) symptoms received a CCM pulse generator. Patients were randomly assigned to Group 1 (n = 80, CCM treatment 3 months, sham treatment second 3 months) or Group 2 (n = 84, sham treatment 3 months, CCM treatment second 3 months). The co-primary endpoints were changes in peak oxygen consumption (VO2,peak) and Minnesota Living with Heart Failure Questionnaire (MLWHFQ). Baseline EF (29.3 ± 6.7% vs. 29.8 ± 7.8%), VO2,peak (14.1 ± 3.0 vs. 13.6 ± 2.7 mL/kg/min), and MLWHFQ (38.9 ± 27.4 vs. 36.5 ± 27.1) were similar between the groups. VO2,peak increased similarly in both groups during the first 3 months (0.40 ± 3.0 vs. 0.37 ± 3.3 mL/kg/min, placebo effect). During the next 3 months, VO2,peak decreased in the group switched to sham (−0.86 ± 3.06 mL/kg/min) and increased in patients switched to active treatment (0.16 ± 2.50 mL/kg/min). MLWHFQ trended better with treatment (−12.06 ± 15.33 vs. −9.70 ± 16.71) during the first 3 months, increased during the second 3 months in the group switched to sham (+4.70 ± 16.57), and decreased further in patients switched to active treatment (−0.70 ± 15.13). A comparison of values at the end of active treatment periods vs. end of sham treatment periods indicates statistically significantly improved VO2,peak and MLWHFQ (P = 0.03 for each parameter). Conclusion In patients with heart failure and left ventricular dysfunction, CCM signals appear safe; exercise tolerance and quality of life (MLWHFQ) were significantly better while patients were receiving active treatment with CCM for a 3-month period.