Angina References
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Braunwald E, Jones RH, Mark DB, Brown J, Brown L, Cheitlin MD, Concannon CA,
Cowan M, Edwards C, Fuster V, et al
Diagnosing and managing unstable angina. Agency for Health Care Policy and
Research.
Circulation 1994 Jul;90(1):613-22

This Quick Reference Guide for Clinicians contains recommendations on the
care of patients with unstable angina based on a combination of evidence
obtained through extensive literature reviews and consensus among members of
an expert panel. Principal conclusions include the following. (1) Many
patients suspected of having unstable angina can be discharged home after
adequate initial evaluation. (2) Further outpatient evaluation may be
scheduled for up to 72 hours after initial presentation for patients with
clinical symptoms of unstable angina judged at initial evaluation to be at
low risk for complications. (3) Patients with acute ischemic heart disease
judged to be at intermediate or high risk of complications should be
hospitalized for careful monitoring of their clinical course. (4)
Intravenous thrombolytic therapy should not be administered to patients
without evidence of ST segment elevation and acute myocardial infarction.
(5) Assessment of prognosis by noninvasive testing often aids selection of
appropriate therapy. (6) Coronary angiography is appropriate for patients
judged to be at high risk for cardiac complications or death based on their
clinical course or results of noninvasive testing. (7) Coronary artery
bypass surgery should be recommended for almost all patients with left main
disease and many patients with three-vessel disease, especially those with
left ventricular dysfunction. (8) The discharge care plan should include
continued monitoring of symptoms; appropriate drug therapy, including
aspirin; risk-factor modification; and counseling.

Rizik DG, Healy S, Margulis A, Vandam D, Bakalyar D, Timmis G, Grines C,
O'Neill WW, Schreiber TL
A new clinical classification for hospital prognosis of unstable angina
pectoris.
Am J Cardiol 1995 May 15;75(15):993-7

ABSTRACT:
Unstable angina represents a heterogeneous spectrum of clinical entities
between chronic stable angina and acute myocardial infarction. To facilitate
prognostication of in-hospital outcome, we prospectively tested on a priori
unstable angina classification scheme based on information available at the
time of acute presentation. Prospective database enrollment at the time of
emergency room presentation was performed and patients were classified into
1 of the following categories: class IA, acceleration of previous exertional
angina without electrocardiographic (ECG) changes; class IB, acceleration of
previous exertional angina with ECG changes; class II, new-onset exertional
angina; class III, new-onset rest angina; class IV, protracted rest angina
with ECG changes. The study consisted of 1,387 consecutive patients with
unstable angina. Baseline demographics and aggregate in-hospital major
cardiac event rates were recorded (myocardial infarction, refractory angina,
and death). There was a significant increasing trend in cardiac events from
class I to IV (p < 0.0001). Class IA patients had the lowest aggregate event
rate at 2.7% (p = 0.0005). Paired chi-square tests of adjacent categories
showed no differences in event rates for class IB and II (p = 0.3). A
significantly higher rate of adverse events was seen for class III patients
(20.1%, p < 0.0001). Class IV patients demonstrated the highest rate of
in-hospital adverse events (42.8%, p < 0.0001). We conclude that this easily
deduced, universally applicable categorization of unstable angina is highly
prognostic of in-hospital adverse cardiac events and hence could have
potential use for triage decisions regarding hospital admission and
intensity of therapy.

Chahine RA
Unstable angina. The problem of definition.
Br Heart J, 37: 12, 1975 Dec, 1246-9

Abstract:
Unstable angina is used interchangeably with a variety of other terms to refer
to a clinical situation intermediate in severity between chronic effort angina
and myocardial infarction. In most reports dealing with this syndrome, the
patients were selected according to a number of criteria which varied from one
study to another. Some authors recognized subgroups of patients with variable
severity while others looked at unstable angina as one single group. This
resulted in conflicting observations and consequent dilemmas in the management
of these patients. Accurate definitions are, therefore, necessary. It is
proposed to divide unstable angina into two main clinical categories. Type I:
This includes three subgroups. (A) Patients with known chronic angina and
sudden or accelerated progression of symptoms; (B) patients with chronic
angina and onset of recurrent attacks at rest; and (C) patients with angina of
recent onset and rapid progression into a severe condition. Type II: (severe
unstable angina). Any of the subgroups described under unstable angina Type I
will qualify for this classification if the patient develops recurrent
episodes of prolonged ischaemic chest pains resistant to nitroglycerin lasting
for 15 minutes or more. Accurate measurement of symptoms and laboratory
criteria are suggested to qualify for the different subgroups of unstable
angina.