Myocardial Ischemia

NEWS & PERSPECTIVE › MULTISPECIALTY Diagnosis and Management of Myocardial Ischemia (Angina) in the Elderly Patient

Donald D. Tresch, MD, Haritha R. Alla, MD, Medical College of Wisconsin, Division of Cardiology and Geriatrics, Milwaukee, WI Disclosures Am J Geriatr Cardiol. 2001;10(6)

An acute MI may be the initial clinical manifestation of CAD in elderly persons, although many elderly persons experience myocardial ischemia for years prior to an acute MI.

Unfortunately, due to the absence of symptoms and the atypical presentation of myocardial ischemia in elderly persons, CAD will not be diagnosed in many of these patients until an acute MI occurs. Numerous studies[4-6] have shown that 20%-50% of patients 65 years or older demonstrate silent myocardial ischemia upon stress testing or ambulatory electrocardiographic (EKG) monitoring.

Moreover, silent myocardial ischemia is a marker for future coronary events in these patients. Nonfatal MI and death are two to three times more common in patients with silent myocardial ischemia than in those without silent ischemia. The event rate is even higher if, in addition to ischemia, abnormal LV function[4,5,7] or ventricular tachyarrhythmias[8,9] are present.

Therefore, detection of silent myocardial ischemia in elderly persons is important. Some authors have concluded that performing stress testing in persons at the time of their retirement would be more cost effective than the usual practice of stress testing the 50-year-old junior executive. Symptoms in elderly patients with myocardial ischemia may be so atypical, compared to younger patients, that the symptoms may be misdiagnosed as being caused by another disorder or as related merely to aging.

Exertional angina pectoris is commonly the first manifestation of CAD in middle-aged persons, and is usually easily recognized due to its typical features. For elderly persons, however, this may not be the case. Due to limited physical exertion, many elderly persons with CAD will not experience exertional angina. Instead of angina, myocardial ischemia in elderly patients is commonly manifested as dyspnea.

Not infrequently, the dyspnea occurs in combination with angina, although the angina is frequently mild and is of little concern to the patients. In other elderly patients, myocardial ischemia appears as shoulder or back pain and may be misdiagnosed as degenerative joint disease; if the pain is localized in the epigastric area, it may be ascribed to peptic ulcer disease.
Positional postprandial epigastric discomfort that is burning in quality is often attributed to hiatal hernia or esophageal reflux, rather than myocardial ischemia.

Moreover, the frequent presence of comorbid conditions in elderly patients adds to the confusion and may lead to a misdiagnosis of symptoms that are actually due to myocardial ischemia.

Myocardial ischemia may be manifested as acute LV failure in elderly patients, with some patients presenting with acute pulmonary edema.[10-13] Chest pain may not be present, although the myocardial ischemia is severe enough to produce diastolic and/or systolic LV dysfunction. Many of these elderly patients are unaware of having CAD until the onset of the acute heart failure.

A history of hypertension is common and the patient's EKG and echocardiogram will demonstrate LV hypertrophy. Three-vessel CAD is usually found, but ventricular systolic function is only mildly depressed. With revascularization, these patients do well.
Cardiac arrhythmias can be another clinical manifestation of myocardial ischemia in elderly patients. Patients with myocardial ischemia may experience chest palpitations caused by ventricular premature beats.

Unfortunately, in other elderly patients, the arrhythmias may be ventricular tachycardia or fibrillation leading to sudden cardiac death. Prior to sudden death, these patients may be asymptomatic, with no awareness of the presence of CAD.

The initial evaluation of an elderly patient with myocardial ischemia should begin with a thorough history and complete physical examination, and determination of the coronary risk factors and comorbid illnesses. In addition, early assessment of clinical stability, with stratification into a high- or low-risk group, is necessary.[14]

In addition to advanced age, mortality and morbidity in elderly patients with myocardial ischemia are directly related to LV function, the extent of CAD, and the presence of comorbidity. Stress testing is important in stratification of elderly patients with myocardial ischemia, especially in asymptomatic patients (Table I).

The goals of treatment in elderly patients with myocardial ischemia are 1) to relieve symptoms, if present, and to stabilize the acute pathophysiologic process; 2) to prevent recurrence or new onset of symptoms; and 3) to prevent progression and induce regression of the underlying pathophysiology to reduce future coronary events, including death.
The specific management of elderly patients with myocardial ischemia consists of 1) treatment of associated disorders that can precipitate or worsen ischemia; 2) reduction of coronary risk factors; and 3) use of pharmacologic agents. In high-risk elderly patients, coronary angiography is necessary, if there are no contraindications to revascularization.