Silent ischemia

They are useful against hypertension but also for cases of angina, heart failure, heart attack, arythmia, silent ischemia, stroke and senility. 

Silent ischemia is atherosclerosis that has begun to affect the heart adversely but does not yet show symptoms. 

Many episodes of ischemia do not cause symptoms of angina (silent ischemia). Patients often have a reproducible pattern of pain or other... 

Do not give dihydroergotamine to patients with ischemic heart disease (angina pectoris, history of Ml, documented silent ischemia) or to patients who have clinical symptoms or findings consistent with coronary artery vasospasm, including Prinzmetal variant angina. 

Contraindications Basilar or hemiplegic migraine, coronary artery disease, ischemic heart disease (including angina pectoris, history of Ml, silent ischemia, and Prinzmetal s angina), uncontrolled hypertension, use within 24 hours of ergotamine-contain-ing preparations or another serotonin receptor agonist, use within 14 days of MAOls... 

FIGURE 22-1 T Myocardial ischemia equation. (Adapted from Miller AB. Mixed ischemic subsets. Comparison of the mechanism of silent ischemia and mixed angina. Am J Med 1985 79 [suppl 3a] 25, with permission.]... 

Stable angina Unstable angina Silent ischemia Number of diseased vessels 62(36) 94(54) 17(10)... 

Braun S, van der Wall EE, Emanuelsson H, Kobrin I. Effects of a new calcium antagonist, mibefradil (Ro 40-5967), on silent ischemia in patients with stable chronic angina pectoris a multicenter placebo-controlled study. The Mibefradil International Study Group. J Am Coll Cardiol 1996 27(2) 317-22. 

It has been convincingly shown that a nitrate-free period reduces nitrate tolerance (72). The modem strategy is to have a nitrate-free period when the patient is asleep, although this results in reduced protection from ischemia in the early morning, the time when many episodes of silent ischemia and myocardial infarction occur. Reports that ACE inhibitors (73) or carvedilol (74) reduce nitrate tolerance are as yet unconfirmed (75). 

IV use ischemic heart disease silent ischemia, Prinzmetal s angina, uncontrolled hypertension, concurrent ergotamine-containing preparations, hemiplegic or basilar migraine Caution with liver and kidney problems... 

Gottlieb SO, Weisfeldt ML, Ouyang P, Mellits ED, Gersten-blith G. Silent ischemia as a marker for early unfavorable outcomes in patients with unstable angina. N Engl J Med 1986 314 1214. 

The initial step in management is to modify the major risk factors for HID—hypertension, hypercholesterolemia, and smoking— and data from the Multiple Risk Factor Intervention Trial (MRFIT) show these interventions to be useful in patients with silent ischemia. In a subset of the study population that had abnormal baseline exercise ECG responses, the special intervention group had a 57% reduction in coronary heart disease death (22.2 of 1000 versus 51.8 of 1000) and a reduction in sudden death resulting from cessation of smoking and lowering of blood pressure and cholesterol when compared with the usual-care group. 

Calcium channel antagonists alone and in combination have been shown to be effective in reducing symptomatic and asymptomatic ischemia however, they do not interrupt the diurnal surge in ischemia observed on ambulatory monitoring, and in general, they are somewhat less effective than /3-blockers for silent ischemia. " Nifedipine in particular seems to provide less protection and provides wide fluctuations in response, with approximate reductions in the number of episodes ranging from 0% to 93% and in duration from 23% to 65% unless combined with /3-blockers. Fewer studies are available with other calcium blockers, and comparative trials are uncommon. 

Singh N, Mironov D, Goodman S, et al. Treatment of silent ischemia in unstable angina A randomized comparison of sustained-release verapamil versus metoprolol. Clin Cardiol 1995 18 653-658. 

Erne P, Schoenenberger AW, Burckhardt D, et al. Effects of percutaneous coronary interventions in silent ischemia after myocardial infarction the SWISSI II randomized controlled trial. JAMA 2007 297(18) 1985-91. 

In the elderly, the symptoms of pain, pressure, or tightness, may he modified and more ill defined actually they may be minimal to absent. Similarly, asymptomatic coronary heart disease with silent myocardial infarction and silent ischemia is more prevalent in the elderly. Epidemiologic studies estimate the prevalence of claudication to be as high as 10%... 

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