ACUTE MI AND OTHER ACUTE CORONARY SYNDROMES:
MANAGEMENT POST-DISCHARGE

I. Risk stratification after acute phase

  1. Stress testing advised 4-14d after MI, in-house or post-discharge
    1. Dipyridamole-Myocardial Perfusion Imaging testing done 2-4d after MI sig. better predictor of of coronary events at 90d than submaximal ETT done 6-12d after MI (Circ. 100:2060, 1999--JW)
    2. Consider PTCA or CABG depending on findings (see Treatment of Stable CAD)
  1. Echo to assess LV function
    1. If low, treat as appropriate for Heart Failure
    2. Consider Automatic Internal Defibrillator if LVEF 30% or less
      1. In a randomized trial of 1232 pts with prior MI and LVEF 30% or less randomized to receive implantable defibrillators or conventional tx; over avg. 20mo f/u, total mortality sig. less (14% vs. 20%) in the defibrillator group; benefit seen across multiple subgroup analyses (NEJM 346:877, 2002--JW)
      2. 674 pts with MI in previous 6-40d and LVEF < 36% randomized to ICD vs. no ICD; over mean 30mo f/u, no sig. diff. in all-cause mortality but ICD group had sig. fewer arrhythmia deaths (12 vs. 29), though sig. more nonarrhythmic cardiac deaths (34 vs. 20). ("DINAMIT" trial; NEJM 351:2481, 2004--JW)
      3. In a study in 898 pts s/p MI with either (LVEF < 40% + HR > 90) or nonsustained ventricular tachycardia randomized to ICD vs. no ICD within 31d after MI; over 3y f/u, ICD recipients had lower incidence of sudden cardiac death but higher incidence of non-sudden cardiac death, and there was no sig. diff. in all-cause mortality ("IRIS" trial; NEJM 361:1427, 2009-JW)
  1. Patients who had thrombolysis with their MI (Circ. 96:748, 1997-abst)
  1. 1008 pts (24-69yo, 80% male) s/p first MI w/no h/o previous CABG or PTCA & no "sig. noncoronary disease" who had had thrombolytics < 12h after onset of MI and who on ETT at hosp. discharge had inducible ischemia randomized to medical management vs. revascularization (36% CABG; 64% PTCA)
  2. Over 4y f/u, no sig. diff. in mortality but sig. less risk in revascularization group for reinfarction and unstable angina.

II. Long-term oral Beta-blockers decrease mortality--See link for the data

III. Long-term antithrombotic treatment

  1. Continue ASA 160-325mg QD indefinitely (or Ticlopidine if ASA is contraindicated)
  2. Warfarin
  1. ACC/AHA guidelines say consider warfarin in high-risk pts (Class IIa for extensive wall motion abnormalities; Class IIb for pts with LV dysfunction, class I for AFib) or pts unable to take daily ASA (class I)
  2. 8803 MI survivors randomized to ASA 160mg/d, ASA 80mg/d + warfarin 1mg/d, or ASA 80mg/d + warfarin 3mg/d. Median f/u 14mos; no sig. diff in combined incidence of MI, CVA, or vascular death or in incidence of bleeding complications ("CARS" study, Lancet 350:389, 1997-JW)
  3. 3630 pts w/p MI randomized to warfarin (target INR 2.8-4.2), ASA 160mg/d, or ASA 75mg/d + warfarin (target INR 2.0-2.5).  Over 4y mean f/u, incidence of (death, MI, or thromboembolic CVA) was 20% in ASA-only group, 16.7% of warfarin-only group (sig. less than ASA-only), and 15% of combined-therapy group (sig. less than ASA-only).  No sig. diff. in this combined outcome between the warfarin-only group and the combined group.  Nonfatal major bleeding sig. more common in both warfarin-containing groups than the ASA-alone group (0.62%/yr vs. 0.17%/yr).  All-cause mortality was not sig. diff. in the 3 groups (NEJM 347:969, 2002--JW)
    999 pts with MI or unstable angina in the prior 8wks randomized to ASA 80mg QD, warfarin (adjusted to target INR 3.0-4.0), or ASA 80mg/d + warfarin (target INR 2.0-2.5); over median 12mo f/u, incidence of (death, recurrent MI, or CVA) was sig. more common in ASA-only pts vs. warfarin-only or combination tx pts (9% vs. 5% and 5%).  Minor bleeding sig. more common in combination-therapy group; All-cause mortality was sig. lower in the warfarin-only group c/w the ASA-only group (1% vs. 4%) but not sig. lower in the combination group c/w the ASA-only group  ("ASPECT-2" study; Lancet 360:109, 2002--JW)
  1. Ximelagatran
    1. 1883 pts with acute MI randomized to ximelagatran vs. placebo; all also received ASA and most also received beta-blockers, ACEI's, and statins. 6mo incidence of (death, nonfatal MI, and severe recurrent ischemia) was sig. lower in ximelagatran recipients (12.7% vs. 16.3%), sig. higher incidence of liver transaminase elevations (16% vs. 4%), and a nonsig. higher incidence of major bleeding (1.8% vs. 0.9%). ("ESTEEM" trial; Lancet 362:789, 2003--JW)
  2. After thrombolysis, ASA rather than warfarin probably best:
    1. 1036 pts s/p tx with anistreplase with acute MI randomized to ASA 150/d vs. warfarin. No diff. in mortality at 3mos but RR 1.9 for CVA or severe bleeding in warfarin users (BMJ 313:1429, 1996-JW)

IV. ACE Inhibitors & Angiotensin Receptor Blockers

  1. 5477 pts > 50yo s/p Q-wave MI or (non-Q-wave MI + CHF diagnosed during hospitalization) randomized to losartan (titrated to target dose 50mg QD) vs. captopril (titrated to target dose 50mg TID).  Over mean f/u of 2.7y, there was a nonsig. lower mortality rate in captopril pts (16% vs. 18%, p = 0.07); no sig. diff. in recurrent MI between the two groups ("Optimaal" trial; Lancet 360:752, 2002--JW)
  2. See also Acute Coronary Syndromes section on data on ACEIs and/or ARBs started very soon after MI

V. Anti-anginals as needed (see Treatment of Stable CAD)

VI. L-Arginine--possibly harmful

  1. In a study in 153 pts with ST-segment-elevation MI randomized to L-arginine (titrated up to 3g TID) vs. placebo, 6mo incidence of (death, MI, or hospitalization for heart feailure) was higher in the L-arginine group (17% vs. 10%) (JAMA 295:58, 2006--JW)

VII. Risk factor control

  1. See also "Dyslipemias" section for discussion of indication for lipid-lowering drugs post-MI; lipid-lowering meds may be beneficial regardles of baseline lipids
  2. Achieve an ideal weight
  3. Smoking cessation if applicable
  4. Consider HRT if postmenopausal female
  5. Diet
    1. A "Mediterranean-style" diet, rich in alpha-linolenic acid, ass'd with sig. decreased risk of all-cause mortality (RR 0.44) and (cardiac death or nonfatal MI) (RR 0.28) in a 11mo randomized trial in 423 survivors of a first MI (Circ. 99:779, 1999--JW)
    2. Consider fish or fish oil
  6. Exercise > 20min at a time > 3x/wk
  7. For pts with Diabetes, intensive glycemic control (IV insulin/glucose x 24h in-hospital then SQ insulin x 3mos) was ass'd with RR of mortality of 0.75 (33% vs. 44%) over avg. 3.4y f/u in a randomized study of 306 pts with acute MI (Circ. 99:2626, 1999--UW Pharm. Letter)

VIII. Keep in mind high prevalence of depression and anxiety after MI

IX. See also Bone Marrow Cell Transfer after MI (click link for details)