PracticeUpdate: Cardiology | Vol1 - No.2 - 2016

CONFERENCE COVERAGE

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European Society of Cardiology Congress 2016 27–31 AUGUST 2016 • ROME, ITALY

One of the largest and most influential cardiovascular meetings globally, this year’s European Society of Cardiology (ESC) Congress saw the release of exciting clinical trial data, some of which were contrary to current clinical practice guidelines. The PracticeUpdate Editorial Team attended the Congress and we bring you coverage of the key clinical trials presented, including two from Australian researchers: the SAVE and NACIAM studies. Implantable cardioverter- defibrillator does not improve overall survival in nonischaemic heart failure Placement of an implantable cardioverter- defibrillator in patients with nonischaemic systolic heart failure did not improve overall survival compared with usual clinical care. Risk of sudden cardiac death, however, was halved, reports the DANISH trial. L ars Kober, MD, of Copenhagen University Hospital, Den- mark, explained that the results suggest a caveat to both European and American Heart Association guidelines that recommend implantable cardioverter-defibrillators for all heart failure. DANISH stands for DANish randomised, controlled, multi- centre study to assess the efficacy of Implantable cardioverter defibrillator in patients with nonischaemic Systolic Heart failure on mortality. Dr Kober said, “Prophylactic cardioverter-defibrillator im- plantation is a class 1 recommendation in patients with heart failure and reduced left ventricular systolic function in both European and American guidelines. The evidence is much weaker, however, for patients with non-ischaemic aetiology. Limited data supports the devices in this population. The DANISH trial filled that gap by suggesting the cardioverter- defibrillators should not be routinely implanted in all patients with systolic heart failure.” A total of 1116 stable patients with chronic, nonischae- mic, symptomatic heart failure were randomised to usual care including guideline-recommended medications such as including beta blockers, renin-angiotensin inhibitors, and mineralocorticoid-receptor antagonists (n = 560); or an im- plantable cardioverter-defibrillator (n = 556). An equal proportion of patients (58%) in both groups also needed cardiac resynchronisation therapy, which was delivered via biventricular pacemaker in the control arm, and a device

that younger patients may experience a survival benefit with implantation of the device.” Fifty-eight percent of controls had received a biventricular pacemaker and device-related infections occurred in both groups. Patients not receiving cardiac resynchronisation therapy in the implantable cardioverter-defibrillator group, however, were at excess risk of device infection (5.1% vs 0.8% in controls; HR 6.35; 95% CI 1.38 to 58.87; P = 0.006). Inappropriate shocks, another risk associated with implantable cardioverter- defibrillators, occurred in 5.9% of the implantable cardioverter- defibrillator group. American Heart Association guidelines include implantable cardioverter defibrillator implantation as a class 1A recommen- dation for primary prevention of all-cause mortality in patients with symptomatic systolic heart failure, with no differentiation between patients with ischaemic and nonischaemic aetiology. European guidelines carry a class IB recommendation specifi- cally for patients with nonischaemic heart failure. Dr Kober concluded, “Guidelines are based on multiple stud- ies. Implantable cardioverter-defibrillator treatment should still carry a class 1A recommendation for prevention of sudden cardiac death in nonischaemic heart failure also. Patients at high risk of non-sudden death, however, may not benefit, and age should be an important factor in the decision to implant the device, along with comorbidities.”

Patients at high risk of non-sudden death ... may not benefit, and age should be an important factor in the decision to implant the device, along with comorbidities.

combining cardiac resynchronisation therapy and implantable cardioverter-defibrillator in the implantable cardioverter- defibrillator arm. After a median of 67.6 months, the primary outcome of death from all causes occurred in 21.6% of implantable cardioverter- defibrillator patients and 23.4% of controls, a nonsignificant difference. Sudden death, a secondary outcome, occurred in 4.3% of implantable cardioverter-defibrillator patients and was almost doubled (8.2%) in the control group (hazard ratio 0.50; 95% confidence interval 0.31 to 0.82; P = 0.01). Results were independent of whether or not a patient received a cardiac resynchronisation device, but an important interaction with age was observed. Dr Kober said, “Patients younger than 68 years of age had a significant reduction in all-cause mortality if they received an implantable cardioverter-defibrillator (hazard ratio 0.64; 95% confidence interval 0.45 to 0.90, P = 0.01), suggesting

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