Myocardial infarction: diltiazem worsened heart failure.

Clinical bottom line (level 1b)

In patients who suffered a myocardial infarction, use of diltiazem had no clear effect on cardiac failure, but it may have increased the risk.
In patients who suffered a myocardial infarction and who had an ejection fraction <0.40, diltiazem caused cardiac failure (NNH = 12 at 25 months) .

Goldstein et al: Circulation 1991; 83 (1): 52-60

Expires March 2003

The study

Double-blinded concealed randomised trial with intention-to-treat
Setting: 38 collaborative hospitals

2453 patients (aged ?, ?% male) post-myocardial infarction

Excluded if

symptomatic hypotension
bradycardia
complicating diseases (undefined)

Note:

Patients were stratified per centre according to baseline days from infarction (cutoff 5d), use of beta-blockers and presence/absence of heart failure (worse than NYHA class I).

Control Group: (n = 1232, 1084 analysed): placebo
Experimental Group: (n = 1221, 1075 analysed): diltiazem 240mg/day orally

97% followed for 25 months congestive cardiac failure (as defined by clinical presentation alone)
Outcome notes:

new congestive cardiac failure (whole study) : (all patients who underwent measurement of ejection fraction; a subset of 88% of total)

The evidence

Outcome	Time to outcome	CER	EER	RRR (95% CI)	ARR (95% CI)	NNT (95% CI)
new congestive cardiac failure (whole study)	25 months	71 (6.55%)	92 (8.56%)	-31% (-76% to 3%)	-2.01% (-4.24% to 0.22%)	-50 (NNT = 24 to infinity; NNH = 454 to infinity)
new congestive cardiac failure (ejection fraction <0.40)	25 months	39 (12.0%)	61 (20.5%)	-72% (-149% to -19%)	-8.58% (-14.4% to -2.79%)	-12 (-36 to -7)

Outcome	Time to outcome	CER	EER	RRR (95% CI)	ARR (95% CI)	NNT (95% CI)
new congestive cardiac failure (ejection fraction >0.40)	25 months	32 (4.22%)	31 (3.98%)	6% (-53% to 42%)	0.24% (-1.75% to 2.22%)	420 (NNT = 57 to infinity; NNH = 45 to infinity)

Comments

Subgroup analysis, although not a priori, is based on factors recognised in other studies as important to the development of cardiac failure.

Citation

Goldstein RE, Boccuzzi SJ, Cruess D, et al: Diltiazem increases late-onset congestive heart failure in postinfarction patients with early reduction in ejection fraction. Circulation 1991; 83 (1): 52-60

Contributor: Bob Phillips and Clare Wotton, November 1999
Reviewer:

_{Clinical Question.}

_Patient	_{myocardial infarction}
_{Intervention or Exposure}	_diltiazem
_Outcome	_{heart failure}