PROACT: Can we Prevent Chemotherapy-related Heart Damage in Patients With Breast Cancer and Lymphoma?

Inclusion Criteria: * Written informed consent. * Adult patients with histopathologically\* confirmed breast carcinoma who have received surgery for their breast cancer; planned to receive 6 cycles of EC 90 (total planned dose 540mg/m2 epirubicin) or FEC 75 (total planned dose 450mg/m2 epirubicin) adjuvant chemotherapy regimen. Patients with HER2+ breast cancer are eligible for inclusion. OR * Adult patients with histopathologically confirmed non-Hodgkin lymphoma (NHL), planned to receive 6 cycles of R-CHOP or CHOP (total planned dose 300mg/m2 doxorubicin) chemotherapy\*\* * Patients with HER2+ breast cancer are eligible for inclusion. \*\* Patients who will receive an alternative anti-CD20 monoclonal antibody are eligible (for example O-CHOP), as long as the total planned doxorubicin dose is ≥300mg/m2 over 6 cycles Exclusion Criteria: * Positive baseline cardiac troponin T (≥14ng/L); * known contraindication to ACE inhibitor e.g. renal artery stenosis, severe aortic stenosis; * are taking, or have a previous intolerance to ACEI (e.g. angioedema); * patient already taking other agents acting on the renin-angiotensin-aldosterone system e.g. Aliskiren, angiotensin receptor blockers (ARBs), Entresto (sacubitril/valsartan), spironolactone, eplerenone; * LVEF \<50%\*; * estimated GFR \< 30 mL/min/1.73m2 at baseline; * hyperkalaemia defined as serum potassium ≥5.5mmol/L; * symptomatic hypotension, or Systolic Blood Pressure \<100mmHg; * poorly-controlled hypertension (Blood Pressure \>160/100mmHg\*\*, or ambulatory BP of 150/95mmHg); * previous myocardial infarction; * known metastatic breast cancer; * previous exposure to anthracycline chemotherapy; * are pregnant or breastfeeding; * previous Herceptin treatment or planned Herceptin treatment within four weeks following anthracycline chemotherapy; * for patients of childbearing potential: refusal to use adequate contraception throughout the trial;\*\*\* * any other invasive cancer diagnosed and treated in the past 5 years; * symptomatic or severe asymptomatic radiation-induced cardiac disease; * judgement by the investigator that the patient has a prognosis of \< 1 year or are unlikely to complete 6 cycles of chemotherapy; * judgement by the investigator that the patient is high risk for tumour lysis syndrome (applicable only to NHL patients); * judgement by the Investigator that the patient should not participate in the study, for example, if the patient is unlikely to comply with study procedures, restrictions, and requirements. \*\<50% as defined by Simpson's biplane method; if absolute measurements are not possible, then a visually normal assessment of LVEF is acceptable for inclusion. \*\*White coat hypertension is more common, and should be ruled out by an ambulatory blood pressure monitor \*\*\*Female patients between the ages of 18 and 50 will receive a pregnancy test at baseline. Adequate methods of contraception are those that can achieve a failure rate of less than 1% per year when used consistently and correctly, such methods include: * combined (estrogen and progestogen containing) hormonal contraception associated with inhibition of ovulation * oral * intravaginal * transdermal * progestogen-only hormonal contraception associated with inhibition of ovulation * oral * injectable * implantable * intrauterine device (IUD) * intrauterine hormone-releasing system (IUS) * bilateral tubal occlusion * vasectomy/vasectomised partner * true sexual abstinence