The Ketogenic Heart Failure Trial

Participants (n= 60) will be randomly assigned to the intervention (n= 30) or control arm (n =30) in a 1:1 ratio. The intervention group will undergo a normocaloric ketogenic dietary intervention diet (with very low carbohydrate [<10% total energy intake], high fat [~70% total energy intake, majority as mono or polyunsaturated fat, <15% as saturated fat] and moderate protein [~20%]). which will be delivered by a qualified dietician either in-person or via telehealth, depending on patient preference and other hospital restrictions. All participants will have the following collected at baseline: - Data collected on background medical history, current medications, cardiovascular risk factors, alcohol intake, smoking and social history as well as LVEF as measured by the most recent cardiac imaging, Heart failure symptoms classified according to NYHA class I-IV, - Measurement of height, weight, waist circumference and blood pressure - Complete self-administered Kansas City Cardiomyopathy questionnaire. - Self-reported dietary intake and exercise questionnaire. - Fasting bloods taken for pathology including pro-BNP level, serum creatinine and electrolytes, liver function, FBC, C-reactive protein (high sensitivity, if available), lipids [TC, LDL, HDL, TG’s] and diabetic profiles (fasting blood glucose level, HbA1C, fasting insulin) - Echocardiography with a left ventricular ejection fraction (LVEF). At the time of the baseline visit, all intervention participants will be instructed in the following: - Instruction on keeping a blood glucose diary (if diabetic) - Instruction on monitoring fluid balance by self-monitoring weight on home scales, monitoring for ankle swelling and shortness of breath - Instruction on keeping a blood pressure diary if the participant owns a home monitor. - Instruction on the use of a food diary and/or smart phone app to record carbohydrate intake per day (grams/day), ideally entered daily, but at least 3 days of the week. - Instruction on performing urine ketone measurements at home on a 3-times per week basis. At 1 week, 1 month and 3 months & 4 months participants will have a telephone review with the study coordinator to: - Obtain any history of syncope, pre-syncope (dizziness/faintness), low blood pressure, low blood glucose, adverse events (see below) or other participant-identified concerns. - Review a diary of blood glucose recordings in patients with diabetes mellitus to identify hypoglycaemia (e.g. a low blood glucose of 4.0mmol/L or less) - Review any home blood pressure recordings or any available in-clinic recordings at the time of seeing their cardiologist/being seen in the heart failure clinic. - Review of the food diary/smart phone app to assess carbohydrate intake. - Record urinary ketone results measured by the participants at home. Patients randomised to the dietary intervention group will undergo in person or telehealth one-on-one consultations with a qualified dietician who will administer the ketogenic diet. The dietary intervention will include oral and written advice on a ketogenic diet, delivered via an initial 45-minute consultation soon after baseline, followed by 20-minute follow-up consultations at 1 week, 2 weeks, 4 weeks, 6 weeks, 8 weeks, 3 months and 4 months (total of 8 dietician visits). Dietary advice will comply with the following: 1. Restriction of carbohydrate to <30 grams carbohydrate/day (a very low carbohydrate intake i.e., <10% total daily intake). 2. Moderate protein intake (~28% total daily intake) and, 3. High healthy fat intake (>60% total daily intake) aiming for ~34% mono-unsaturated fat, 14% polyunsaturated fat and 12% saturated fat. The food diary or smart phone app will be reviewed for compliance and advice provided. Patients will be asked to calculate grams per day of carbohydrates using a dietary app and/or asked to record grams per day in a smart phone app or via a food diary. Education of foods to consume in large amounts, moderate amounts and low amounts within the recommended diet will be provided both verbally and in written form. All participants (intervention and control) will undergo a final in-person 4-month follow up: - Clinical history obtained on adverse events, new medical diagnoses, worsening heart failure episodes, urgent/unplanned doctor visits or pathology, emergency presentations, heart failure hospitalizations, major cardiovascular events, current medications, alcohol intake and smoking. - Heart failure symptoms classified according to NYHA class I-IV. - Measurement of weight, waist circumference, fluid status and blood pressure. - Complete self-administered Kansas City Cardiomyopathy questionnaire. - Self-reported dietary intake and exercise questionnaire. - Fasting bloods taken for pathology including pro-BNP level, serum creatinine and electrolytes, liver function, FBC, C-reactive protein (high sensitivity, if available), lipids [TC, LDL, HDL, TG’s] and diabetic profiles (fasting blood glucose level, HbA1C, fasting insulin) - Echocardiography with LVEF Adherence to the study intervention will be measured by the percentage of consultations attended, with reasonable compliance defined as =>70% dietician attendance, as well as the proportion of participants who achieve ketosis as measured by the presence of urine ketones in =>70% of urine ketone measures at each time point. Adherence will secondarily be assessed by review of patient diary showing a self-reported carbohydrate intake of less than or equal to 30 grams/day.