If, despite the above measures, patients on HFrEF are still symptomatic, specialist advice should be sought. Treatment options include: 

• Consideration for a pacing device that may help improve cardiac contractility +/- a defibrillator function capable of delivering an electric shock if the patient experiences a ventricular arrhythmia
• The addition of ivabradine to improve heart rate control. This may be prescribed in addition to the maximum tolerated dose of a beta-blocker for patients within sinus rhythm whose heart rate is still above 75 beats minute
• Switching the ACEI/ARB to the more recently introduced sacubitril + valsartan (Entresto). Sacubitril acts to reduce the damage to the heart as a result of increased natriuretic peptides that are released when the heart muscle is overstretched. It is prescribed in combination with the ARB valsartan and the combination is known as an ARNI. When starting the treatment any ACEI must be stopped for at least 36 hours before the first dose of sacubitril + valsartan is given as there is a risk of angio-oedema if they are co-prescribed. Any other ARB needs to be discontinued as the product contains valsartan but a wash out period is not required
• Other options may include prescribing a combination of hydralazine and nitrates or the use of digoxin for its inotropic properties.