Aronow 1993.

Study characteristics
Methods	Study design: parallel RCT Centres: not reported Start of enrolment: not reported End of enrolment: not reported Mean follow‐up: 3 months Run‐in period: 2 mornings of control period
Participants	Inclusion criteria: "New York Heart Association functional class III CHF associated with prior myocardial infarction and normal LV ejection fraction (>50%) who were able to perform a maximal treadmill exercise test were included in the study". Exclusion criteria: "No patient had valvular heart disease, systolic blood pressure ~100 mm Hg, lung disease, hepatic disease or renal insufficiency." Randomised (N): 21 (10 intervention, 11 control) Withdrawn (N): not reported Lost to follow‐up (N): not reported Analysed (N): not reported Age (years, mean, SD): intervention: 80, 3; control: 79, 4 Sex (% men): 14.3 Ethnicity (%): not reported Systolic blood pressure (mmHg, mean, SD): intervention: 126, 12; control: 127, 10 Heart rate (beats/min, mean, SD): intervention: 85, 6; control: 84, 3 BMI not reported Serum creatinine not reported B‐type natriuretic peptide (pg/mL): not reported NT pro B‐type natriuretic peptide (pg/mL): not reported LVEF (%, mean, SD): intervention: 64, 9; control: 64, 7 NYHA class I (%): 0 NYHA class II (%): 0 NYHA class III (%): 100 NYHA class IV (%): 0 Hypertension not reported Diabetes not reported Atrial fibrillation not reported Hospitalisation for heart failure: not reported Coronary heart disease not reported Stroke not reported Diuretic (%): 100 Digoxin (%): 0 Beta‐blocker (%): 0 ACEI study drug ARB not reported MRA not reported
Interventions	Intervention: enalapril. "The initial dose of enalapril was 2.5 mg/day, which was increased to 5 mg/day during week 2, to 10 mg/day (5 mg twice daily) during week 3, to 15 mg/day (7.5 mg twice daily) during week 4 and up to a maximum of 20 mg (10 mg twice daily) during week 5, tf tolerated. If the patient developed symptomatic hypotension or an increase in serum creatinine level, the dose of enalapril was reduced to the previous dose. At the time of the follow‐up studies, 3 months after beginning enalapril, the dose of enalapril was 2.5 mg/day in 1 patient, 5 mg/day in 1 patient, 10 mg/day in 3 patients, 1.5 mg/day in 2 patients, and 20 mg/day in 3 patients." Comparator: no treatment Concomitant medication: "All patients received diuretic treatment with furosemide for ~2 weeks before the beginning of the study and a constant dose of furosemide during the study. Digitalis and other cardiac drugs (except enalapril) were not administered to any patient during the study."
Outcomes	Planned: not reported Reported: NYHA class, blood pressure, heart rate, cardiothoracic ratio, treadmill exercise time, LVEF, peak mitral E/A ratio, left ventricular mass
Notes	no outcome data relevant for this review.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	not reported
Allocation concealment (selection bias)	Unclear risk	not reported
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	not reported
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	"Chest roentgenograms were interpreted by a radiologist who was unaware of the study medication. M‐mode, 2‐ dimensional and pulsed‐wave Doppler echocardiograms were interpreted by an experienced echocardiographer (IK) who was unaware of the study medication. Treadmill exercise tests were performed under the guidance of the senior author who was aware of which patients were receiving enalapril."
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	not reported
Selective reporting (reporting bias)	Unclear risk	not reported
Other bias	Unclear risk	unable to assess