270
JACC: HEART FAILURE VOL. 3, NO. 3, 2015
Letters to the Editor
MARCH 2015:267–72
of discharge (e.g., edema). Despite this, their natriuretic peptide levels remain persistently high, which suggests that they are being sent home with relatively high ventricular filling pressures (2). We call this “hemodynamic” congestion, which reflects an increase in intravascular volume. In the first few weeks
Please note: Dr. Fonarow has received research support from the Agency for Healthcare Research and Quality and has consulted for Medtronic, Gambro, and Novartis. Dr. Gheorghiade has consulted for Abbott Laboratories, Astellas, Astra Zeneca, Bayer Schering Pharma AG, CorThera, Inc., Cytokinetics, Inc., DebioPharm SA, Errekappa Terapeutici (Milan, Italy), GlaxoSmithKline, Johnson & Johnson, Medtronic, Merck, Novartis Pharma AG, Otsuka Pharmaceuticals, Pericor Therapeutics, Protein Design Laboratories, Sanofi, Sigma Tau, and Solvay Pharmaceuticals. Dr. Vaduganathan has reported that he has no relationships relevant to the contents of this paper to disclose.
after discharge, a significant number of patients develop worsening congestion that requires hospi-
REFERENCES
talization. This is due to abnormal hemodynamics,
1. Vaduganathan M, Fonarow GC, Gheorghiade M. Drug therapy to reduce
mainly an increase in pulmonary capillary wedge
early readmission risk in heart failure: ready for prime time? J Am Coll Cardiol HF 2013;1:361–4.
pressure and/or a low cardiac output. Early readmission is often not related to progression of heart failure but to less than optimal treatment of congestion during hospitalization. In patients with left ventricular systolic dysfunction, the maintenance of cardiac output may be achieved by a compensatory increase in heart rate, which is a poor prognostic indicator (3). Thus, elevated heart rate may be a marker rather
than
a
therapeutic
target.
Accordingly,
reducing heart rate that is compensatory may worsen
2. Ambrosy AP, Pang PS, Khan S, et al. Clinical course and predictive value of congestion during hospitalization in patients admitted for worsening signs and symptoms of heart failure with reduced ejection fraction: findings from the EVEREST trial. Eur Heart J 2013;34:835–43. 3. Greene SJ, Vaduganathan M, Wilcox JE, et al. The prognostic significance of heart rate in patients hospitalized for heart failure with reduced ejection fraction in sinus rhythm: insights from the EVEREST (Efficacy of Vasopressin Antagonism in Heart Failure: Outcome Study With Tolvaptan) trial. J Am Coll Cardiol HF 2013;1:488–96. 4. Ambrosy AP, Butler J, Ahmed A, et al. The use of digoxin in patients with worsening chronic heart failure: reconsidering an old drug to reduce hospital admissions. J Am Coll Cardiol 2014;63:1823–32.
hemodynamics and therefore precipitate clinical congestion. To the best of our knowledge, ivabradine is not known to improve hemodynamics other than
Coenzyme Q10
by its predominant effect in decreasing heart rate.
Will This Natural Substance Become a
Alternatively, reduction in heart rate during or early
Guideline-Directed Adjunctive Therapy
after hospitalization could be of benefit in those pa-
in Heart Failure?
tients whose increase in heart rate is not compensatory. We need to keep in mind that the retrospective analysis by Dr. Borer and colleagues was conducted
Ezekowitz expressed in an editorial comment (1)
in patients already receiving ivabradine. This is
his opinion about the Q-SYMBIO study (Coenzyme
different than starting ivabradine pre-discharge or
Q10 as adjunctive treatment of chronic heart failure:
soon after discharge in the vulnerable phase during
a randomised, double-blind, multicentre trial with
which hemodynamics continue to be abnormal and
focus
often worsens. We welcome a prospective study
Natriuretic Peptide (BNP)], and long-term Outcome
assessing the effects of ivabradine started prior to or
[hospitalisations/mortality]) (2) with the follow-
on
SYMptoms,
BIomarker
status
[Brain-
soon after discharge in patients hospitalized for
ing conclusion: “Heart failure (HF) patients are
heart failure. We recommend that congestion during
spending a lot of energy trying to be normal. Let us
the vulnerable phase be effectively treated with loop
help them.”
diuretic, mineralocorticoid receptor antagonist, and
Yes. HF is a disabling disease with a poor prognosis
digoxin therapy. In terms of digoxin, it is known to
despite significant advances in drug and device-based
have very little effect on the sinus node, and the
therapies. The results of the Q-SYMBIO study
decrease in heart rate is secondary to an improve-
demonstrate that supplementation with coenzyme
ment in hemodynamics that is noted within hours
Q 10 (CoQ10) in addition to conventional therapy: 1)
after it is administered (4).
improves symptoms; 2) improves survival; and 3) reduces hospitalization rate. Yes. The investigators are encouraged about the
*Mihai Gheorghiade, MD Muthiah Vaduganathan, MD, MPH Gregg C. Fonarow, MD
study outcomes. The number of patients needed to
*Center for Cardiovascular Innovation
to 10 based on the hazard ratio (in favor of CoQ10) and
Northwestern University Feinberg School of Medicine
the survival rate at 2 years. This estimate of NNT is
201 East Huron, Galter 3-150
low compared with NNTs in other HF trials.
Chicago, Illinois 60611
treat (NNT) for 2 years to prevent 1 death is calculated
Yes. CoQ10 is necessary for the normal function of
E-mail: [emailprotected]
all cells, and supplementation with CoQ10 has been
http://dx.doi.org/10.1016/j.jchf.2014.12.010
clinically tested in various disease states in more than
JACC: HEART FAILURE VOL. 3, NO. 3, 2015
Letters to the Editor
MARCH 2015:267–72
200 randomized controlled trials (RCT) as listed on Medline. None of these trials have reported serious adverse effects. A few incidences of mild gastrointestinal discomfort have been registered, probably due to the vegetable solvent in the capsule and not by
2. Mortensen SA, Rosenfeldt F, Kumar A, et al. The effect of coenzyme Q10 on morbidity and mortality in chronic heart failure results from Q-SYMBIO: a randomized double-blind trial. J Am Coll Cardiol HF 2014;2:641–9. 3. The CONSENSUS Trial Study Group. Effects of enalapril on mortality in severe congestive heart failure. Results of the Cooperative North Scandinavian Enalapril Survival Study (CONSENSUS). N Engl J Med 1987;316:
CoQ10 per se. The 42% lower all-cause mortality in
1429–35.
the CoQ10 group in the Q-SYMBIO study compared
4. Packer M, Colucci WS, Sackner-Bernstein JD, et al., for the PRECISE Study Group. Double-blind, placebo-controlled study of the effects of carvedilol in patients with moderate to severe heart failure. The PRECISE Trial. Circulation 1996;94:2793–9.
with placebo is indicative of the safety profile. The preparation used in the Q-SYMBIO trial (Myoqinon) is a licensed medicinal product in Hungary, a European Union Member, for adjunctive treatment of HF, which further supports the safety of CoQ10.
5. Hunt SA, Abraham WT, Chin MH, et al. ACC/AHA 2005 guideline update for the diagnosis and management of chronic heart failure in the adult. A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol 2005;46:e1–82.
Ezekowitz (1) questions whether the results of the Q-SYMBIO study would be replicable in a larger study. It is unlikely to be a large-scale trial, as funding is difficult when using a nonpatentable substance. A confirmatory trial with CoQ10 could be done, but then
REPLY: Coenzyme Q10 Will This Natural Substance Become a Guideline-Directed Adjunctive Therapy in Heart Failure?
the important question would be, is it ethical to wait for the results of a new trial with the present survival data in Q-SYMBIO study? RCTs with a similar size as the Q-SYMBIO study have been guideline changing in HF. The CONSENSUS I (Cooperative North Scandinavian Enalapril Survival Study) (3) from 1987 with enalapril of 253 patients changed clinical practice in HF. Also, the initial betablocker trials had fewer patients enrolled compared with the Q-SYMBIO study, for example, the PRECISE trial (4) with 278 patients. CoQ10 was acknowledged in a previous American College of Cardiology/American Heart Association HF guidelines from 2005 (5) to have a possible effect in some studies, but supplementation was not recommended until more data were available. The positive survival data from the Q-SYMBIO study and the meta-analyses of RCTs regarding ejection fraction and/or New York Heart Association classification give us a more robust documentation for CoQ10 treatment in HF. Unlike
current
pharmacological
interventions,
CoQ10 supplementation restores a deficiency state that may otherwise contribute to symptoms and reduced survival in patients with HF.
Dr. Mortensen raises a number of points that need clarification and context. First,
the
references
to
current
therapeutics
(angiotensin-converting enzyme inhibitor and betablocker) success in smaller clinical trials are taken out of context. A practice change and recommendations occurred after the confirmatory adequately powered randomized controlled trials (RCTs) were complete. Other therapies have not made it by this necessary hurdle as a result of lack of efficacy or safety. On the basis of Dr. Mortensen’s rationale, many nonefficacious and potentially toxic medications would be on the market and in patient pill bottles had the adequately powered RCT not been done. Second, although promising, safety is not established (1). Lack of reporting to regulatory authorities does not mean lack of safety events, because coenzyme Q 10 (CoQ10) is not subject to any rigorous reporting such as post-marketing surveillance. Clinical trials are only 1 method to review safety and an imperfect one given the narrow inclusion and broad exclusion criteria. In the PubMed search of the same articles mentioned, which includes many single-arm
*Svend Aage Mortensen, MD, DMSc
noncontrolled studies, safety assessment is of mixed
*Heart Center
reporting quality.
Copenhagen University Hospital
Third, other nonpatentable intervention trials have
B 2141, Blegdamsvej 9
been completed and successfully changed clinical
Copenhagen DK-2100
practice, so as originally stated, it behooves the clin-
Denmark
ical and scientific community to seek appropriate
E-mail: [emailprotected]
funding for the adequately powered RCT. Much like
http://dx.doi.org/10.1016/j.jchf.2014.12.006
the trials of statins that were said to be “unethical” because of fixed beliefs that statins improve out-
REFERENCES
comes in patients with HF, it was ethical, and statins
1. Ezekowitz JA. Time to energize coenzyme Q10 for patients with heart fail-
did not reduce clinical events (2). Perhaps the ethical
ure? J Am Coll Cardiol HF 2014;2:650–2.
dilemma of recommending a therapy without proven
271
