I Can’t believe that they actually did a study to figure this out! And ICD is just to stop firibiulation of the heart. Nothing else.
by Crystal Phend
Senior Associate Editor, MedPage Today
This article is a collaboration between MedPage Today® and: Medpage Today
Implantable cardiac defibrillators (ICD) don’t reduce mortality risk in heart failure from non-ischemic causes, the randomized DANISH trial showed.
The primary endpoint of death from any cause occurred in a similar 21.6% of the patients who had devices implanted compared with 23.4% of patients who received usual care over a median follow-up of almost 68 months in the trial (hazard ratio 0.87, 95% CI 0.68-1.12, P=0.28), Lars Kober, MD, DMSc, of Rigshospitalet at the University of Copenhagen, and colleagues reported in the New England Journal of Medicine.
While there was a mortality benefit among people age 68 and younger with ICD treatment (HR 0.64, 95% CI 0.46-0.91), there was a nonsignificant trend for harm in older patients (HR 1.2, 95% CI 0.81-1.72) and no benefit in almost any of the other demographic and comorbidity measures.
There was benefit in preventing sudden cardiac death (4.3% with ICD versus 8.2% without, HR 0.50, 95% CI 0.3-0.82, P=0.005) but not in preventing overall cardiovascular death or noncardiovascular death.
“In both European and U.S. guidelines, prophylactic implantation of an ICD is a Class 1 recommendation for patients with heart failure and reduced left ventricular systolic function,” the authors wrote. “However, the evidence for a benefit is much stronger for patients with ischemic heart disease than it is for patients with heart failure from other causes.”
As to the age interaction, Kober said: “If you are older and you are likely to have more co-morbidities and therefore the risk of dying from any cause is greater.”
The findings confirm “what we knew: ICDs prevent sudden cardiac death,” said Mariell L. Jessup, MD, of the Penn Heart and Vascular Center. But Jessup, who is on writing committees for both U.S. and European heart failure guidelines, said the DANISH findings were unlikely to change current guidelines.
Mary Norine Walsh, MD, of St. Vincent’s Heart Center in Indianapolis and president-elect of the American College of Cardiology, told MedPage Today that “this study will change my practice, in that it is more information to give to patients who have non-ischemic cardiomyopathy with whom I am having a discussion about primary prevention therapy with an ICD … it will lengthen the conversation we have with our patients.”
The trial — Danish Study to Assess the Efficacy of ICDs in Patients with Non-ischemic Systolic Heart Failure on Mortality — included 556 patients randomized to receive an ICD and another 560 patients to the usual care arm of the study, which could include the use of cardiac resynchronization therapy (58% of the patients in each group received CRT). Participants had with systolic heart failure with left ventricular ejection fraction or less of 35% that was not caused by coronary artery disease. The findings were also presented at the European Society of Cardiology meeting.
In an accompanying editorial, John J.V. McMurray, MD, at the University of Glasgow, wrote that “the absolute benefit of ICDs in a typical and well-treated population with heart failure might be small. ICDs are expensive and not without adverse effects. It is, therefore, desirable to avoid their use in patients who are unlikely to obtain a worthwhile benefit.”
The ICD devices cost $30,000 to $50,000, depending on make, model and configuration. Device infection occurred in 4.9% of the ICD patients and in 3.6% of the control group (P=0.29).
The findings highlighted the importance of targeting ICDS to patients who are likely to benefit the most — “that is, those who remain at high absolute risk for sudden cardiac death despite receiving the best available pharmacologic and device therapy,” McMurray stated.
He warned that “the results of the DANISH trial coupled with the generally infrequent use of ICDs globally, should open a debate about whether it is ethical to conduct new ICD trials involving the highest-risk patients. The challenge is how to identify such patients.”
The trial was supported by unrestricted grants from Medtronic, St. Jude Medical, TrygFonden, and the Danish Heart Foundation.
Kober disclosed relevant relationships with Sanofi and Novartis.
McMurray disclosed relevant relationships with Cardiorentis, Amgen, Novartis, Oxford University/Bayer, GlaxoSmithKline, Theracos, AbbVie, AstraZeneca, Vifor-Fresnius Pharma, DalCor, Pfizer, Merck, and Bristol-Myers Squibb.