5. What is the effect of treatment with beta-blockers in non-oncology populations with asymptomatic cardiomyopathy?
First Author Year	Study Designh Treatment era Years of follow-up	Participants	Treatment	Main outcomes	Addt’l remarks
Dargie64 2001	Double-blind, placebo-controlled RCT 1.3 years clinical follow-up	1959 patients with MI 3–21 days before randomization, EF≤ 40% or wall-motion score index ≤ 1.3 and at least 24 hours on a stable dose of ACE-inhibitor treatment.	Carvedilol: N=975 Placebo: N=984	All-cause mortality: Carvedilol: 116 (12%) Placebo: 141 (15%) HR: 0.77 (0.60 – 0.98) Hospitalization for heart failure: Carvedilol: 118 (12%) Placebo: (138 (14%) HR 0.86 (0.67 – 1.09)	Eligible patients had LV dysfunction with or without heart failure, but patients with severe heart failure were excluded. EF was determined by echocardiography, RNA or ventriculography
Exner65 1999	Retrospective analysis of RCT Mean followup 35 months	4228 patients participating in the SOLVD prevention trial	Patients that used a beta blocker at the start of the trial, in addition to study medication: N=1015 (24%) Patients that did not use a beta blocker at the start of the trial, in addition to study medication: N=3213 (76%)	All-cause mortality: Using a beta blocker: IR 4.3/100 person-years No beta blocker: IR 5.6/100 person-years Multivariate model, using a beta blocker in addition to ACE inhibitor allocation: * All-cause mortality RR 0.70 * All-cause mortality or hospitalization for CHF: RR 0.64 (0.49 – 0.83)
Vantrimpont66 1997	Retrospective analysis of RCT Mean clinical follow-up of surviving patients: 42 months (+/−10 months)	2231 patients participating in the SAVE trial	Patients that used captopril at the start of the trial, in addition to study medication: N=789 (35%) Patients that did not use captopril at the start of the trial, in addition to study medication: N=1442 (65%)	Cardiovascular mortality: Captopril: 13.1% No captopril: 22.1% (RR 0.58, 0.43 – 0.79) Severe heart failure: Captopril: 16.5% No captopril: 22.6% (RR 0.68, 0.55 – 0.83) Multivariate model (including captopril use): * CV mortality RR 0.70 * Severe CHF RR 0.79
Hunt61,62 AHA/ACC Guideline (2005 and 2009)	Beta-blockers are indicated in all patients without a history of MI who have a reduced LVEF with no HF symptoms	Stage B*		Class of recommendation I Level of evidence C