Modification of age-related changes in cardiovascular structure and function using exercise training

Increasing age is associated with substantial changes in cardiovascular structure and function, the cause and permanence of which are unknown. Diastolic function in particular alters appreciably in older adults but non-invasive measurement of cardiac function during diastole has significant limitations. Magnetic resonance imaging with tagging was used to identify changes in three dimensional myocardial strain in older compared to young normal volunteers. This technique identified significantly delayed myocardial relaxation with more myocardial strain persisting in early diastole in older compared to younger individuals. These findings were thought to be attributable to the aging process.Epidemiological studies and small, non-randomised trials suggest that physical activity might slow cardiovascular aging and improve diastolic function in older adults. A randomised controlled trial was therefore performed to assess whether exercise training could modify age-related changes in older, normal volunteers who had been screened to exclude significant cardiovascular disease. The intervention group underwent six months of supervised exercise training whilst participants in the control group were asked to maintain their pre-trial levels of activity. Measurements made at baseline and after six months included transthoracic echocardiography, cardiac MRI, body composition, blood lipid concentrations, applanation tonometry, quality of life and maximal exercise capacity.Despite significant increases in exercise capacity in the intervention group, no other significant changes in cardiovascular structure or function, body composition, cholesterol concentration or quality of life were observed when compared to changes seen in the control group.Six months of exercise training in previously sedentary older adults are insufficient to modify cardiovascular function and structure despite causing marked improvements in exercise capacity. These findings contrast with previously reported non-randomised trials of exercise training in older people. However, they add important, robust information regarding the likely effects of short periods of exercise training on cardiovascular function and structure in older normal adults

Preventing cardiotoxicity in patients with breast cancer and lymphoma: protocol for a multicentre randomised controlled trial (PROACT)

Introduction: Anthracyclines are included in chemotherapy regimens to treat several different types of cancer and are extremely effective. However, it is recognised that a significant side effect is cardiotoxicity; anthracyclines can cause irreversible damage to cardiac cells and ultimately impaired cardiac function and heart failure, which may only be evident years after exposure. The PROACT trial will establish the effectiveness of the ACE inhibitor enalapril maleate (enalapril) in preventing cardiotoxicity in patients with breast cancer and non-Hodgkin’s lymphoma (NHL) receiving anthracycline-based chemotherapy. Methods and analysis: PROACT is a prospective, randomised, open-label, blinded end-point, superiority trial which will recruit adult patients being treated for breast cancer and NHL at NHS hospitals throughout England. The trial aims to recruit 106 participants, who will be randomised to standard care (high-dose anthracycline-based chemotherapy) plus enalapril (intervention) or standard care alone (control). Patients randomised to the intervention arm will receive enalapril (starting at 2.5 mg two times per day and titrating up to a maximum dose of 10 mg two times per day), commencing treatment at least 2 days prior to starting chemotherapy and finishing 3 weeks after their last anthracycline dose. The primary outcome is the presence or absence of cardiac troponin T release at any time during anthracycline treatment, and 1 month after the last dose of anthracycline. Secondary outcomes will focus on cardiac function measured using echocardiogram assessment, adherence to enalapril and side effects. Ethics and dissemination: A favourable opinion was given following research ethics committee review by West Midlands—Edgbaston REC, Ref: 17/WM/0248. Trial findings will be disseminated through engagement with patients, the oncology and cardiology communities, NHS management and commissioning groups and through peer-reviewed publication

Preventing Cardiac Damage in Patients Treated for Breast Cancer and Lymphoma: The PROACT Clinical Trial

BackgroundCardiotoxicity is a concern for cancer survivors undergoing anthracycline chemotherapy. Enalapril has been explored for its potential to mitigate cardiotoxicity in cancer patients. The dose-dependent cardiotoxicity effects of anthracyclines can be detected early through the biomarker cardiac troponin.ObjectivesThe PROACT (Preventing Cardiac Damage in Patients Treated for Breast Cancer and Lymphoma) clinical trial assessed the effectiveness of enalapril in preventing cardiotoxicity, manifesting as myocardial injury and cardiac function impairment, in patients undergoing high-dose anthracycline-based chemotherapy for breast cancer or non-Hodgkin lymphoma.MethodsThis prospective, multicenter, open-label, randomized controlled trial employed a superiority design with observer-blinded endpoints. A total of 111 participants, scheduled for 6 cycles of chemotherapy with a planned dose of ≥300 mg/m2 doxorubicin equivalents, were randomized to receive either enalapril (titrated up to 20 mg daily) or standard care without enalapril.ResultsMyocardial injury, indicated by cardiac troponin T (≥14 ng/L), during and 1 month after chemotherapy, was observed in 42 (77.8%) of 54 patients in the enalapril group vs 45 (83.3%) of 54 patients in the standard care group (OR: 0.65; 95% CI: 0.23-1.78). Injury detected by cardiac troponin I (>26.2 ng/L) occurred in 25 (47.2%) of 53 patients on enalapril compared with 24 (45.3%) of 53 in standard care (OR: 1.10; 95% CI: 0.50-2.38). A relative decline of more than 15% from baseline in left ventricular global longitudinal strain was observed in 10 (21.3%) of 47 patients on enalapril and 9 (21.9%) of 41 in standard care (OR: 0.95; 95% CI: 0.33-2.74). An absolute decline of >10% to <50% in left ventricular ejection fraction was seen in 2 (4.1%) of 49 patients on enalapril vs none in patients in standard care.ConclusionsAdding enalapril to standard care during chemotherapy did not prevent cardiotoxicity in patients receiving high-dose anthracycline-based chemotherapy. (PROACT: Can we prevent Chemotherapy-related Heart Damage in Patients With Breast Cancer and Lymphoma?; NCT03265574