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  Contents copyright 1994, Mass. Medical Society.

Journal Watch Summaries for August 30, 1994

ATENOLOL IS FOUND BENEFICIAL FOR SILENT ISCHEMIA.
  Circulation 1994 Aug; 90:762-8.

PREOPERATIVE TESTING WITH DIPYRIDAMOLE THALLIUM.
  Am J Cardiol 1994 Aug 15; 74:311-7.

BETTER OUTCOMES AFTER SURGERY FOR MITRAL
REGURGITATION.
  Circulation 1994 Aug; 90:830-7.

EYE DISEASE IN AMBULATORY PATIENTS.
  Arch Intern Med 1994 Aug 22; 154:1821-8.

SYMPTOM-TRIGGERED TREATMENT FOR {*filter*} WITHDRAWAL.
  JAMA 1994 Aug 17; 272:519-23.

PERINATAL MEASLES AND CROHN'S DISEASE.
  Lancet 1994 Aug 20; 344:508-10.

ATENOLOL IS FOUND BENEFICIAL FOR SILENT ISCHEMIA.
   The question of treating myocardial ischemia that
causes few or no symptoms is controversial, especially now
that silent ischemia is more readily detected by ambulatory
electrocardiographic monitoring (see Journal Watch accession
number 940715001). Support for aggressive treatment is
provided by this multicenter, randomized, double-blind study
of 306 patients with asymptomatic or mildly symptomatic
ischemia and documented coronary disease.
   The patients received either the beta-blocker atenolol
(100 mg daily) or placebo. Those whose symptoms placed them
in Canadian functional class III or IV were excluded. After
four weeks, patients taking atenolol had about half as much
ischemia detected by ambulatory ECGs as the placebo group.
During an average follow-up of 10.4 months, there were 56
adverse events ranging from worsening of angina to death.
The atenolol group had fewer events (relative risk, 0.44)
and remained event-free for longer (mean, 120 vs. 79 days).
Abolition of ECG-detected ischemia at four weeks reduced the
relative risk for adverse events at one year to 0.42.
   Comment: These data bolster the theory that treatment of
silent ischemia can improve outcomes in patients with
coronary disease, but this must be considered only a theory
until a clear benefit is shown in larger, longer-term trials
using the "harder" individual endpoints of MI and mortality.
--TH Lee.
   Citation: Pepine CJ; et al. Effects of treatment on outcome in mildly
symptomatic patients with ischemia during daily life: the Atenolol
Silent Ischemia Study (ASIST). Circulation 1994 Aug; 90:762-8.

PREOPERATIVE TESTING WITH DIPYRIDAMOLE THALLIUM.
   Surgical patients who are at intermediate to high risk
for coronary heart disease on clinical exam often undergo
preoperative risk stratification using intravenous
dipyridamole thallium-201 myocardial scintigraphy. This
study evaluated both the prognostic and therapeutic
usefulness of such testing in 161 consecutive men and women
referred for thallium testing before major noncardiovascular
surgery.
   As expected, abnormal thallium scans significantly
predicted perioperative cardiac death, myocardial
infarction, and any cardiac event. Of the 72 patients with
abnormal scans, 36 received therapeutic interventions before
surgery (changes in antiischemic medical therapy or coronary
revascularization) at their physicians' discretion. Patients
receiving these interventions had significant reductions in
perioperative deaths or infarctions (6 vs. 31 percent) and
all cardiac events (8 vs. 47 percent).
   Comment: This study suggests that interventions based on
preoperative thallium testing can reduce cardiac morbidity
and mortality in surgical patients with evidence of CAD.
Whether some of the beneficial therapeutic changes would
have been made in the absence of thallium testing is
uncertain. --CD Mulrow.
   Citation: Younis L; et al. Preoperative clinical assessment and
dipyridamole thallium-201 scintigraphy for prediction and prevention of
cardiac events in patients having major noncardiovascular
surgery and known or suspected coronary artery disease.
Am J Cardiol 1994 Aug 15; 74:311-7.

BETTER OUTCOMES AFTER SURGERY FOR MITRAL REGURGITATION.  
The timing of valve surgery for mitral regurgitation
is one of the most difficult decisions in cardiovascular
medicine. This observational study of 409 consecutive
patients from the Mayo Clinic, who had surgery for isolated
mitral regurgitation during the 1980s, provides insight into
the likelihood of operative mortality.
   Rates of death before discharge declined from 11 percent
during 1980-1984 to 4 percent during 1985-1989. Operative
mortality was only 1.5 percent among patients in New York
Heart Association functional class I or II, and was only 1.1
percent in patients under age 75 during 1985-1989. Overall
long-term survival was 75 percent at five years and 58
percent at 10 years. Multivariate analysis identified
several independent preoperative predictors of survival:
ejection fraction on echocardiography, age, creatinine
level, presence of coronary artery disease, year of
operation, and NYHA functional class.
   Comment: These data show marked improvement in survival
after surgery for mitral regurgitation, particularly for
patients under age 75, reflecting recent technical advances.
The low overall mortality in young patients and the higher
mortality in patients with low ejection fractions suggest
that valve surgery should be considered earlier in the
natural history of mitral regurgitation, perhaps even before
left-ventricular dysfunction is manifest. --TH Lee.
   Citation: Enriquez-Sarano M; et al. Echocardiographic prediction of
survival after surgical correction of organic mitral regurgitation.
Circulation 1994 Aug; 90:830-7.

EYE DISEASE IN AMBULATORY PATIENTS.
   This study of the prevalence of previously known and
undetected eye disease finds many patients in need of
intervention. Investigators screened 405 patients over age
39 attending a general medicine clinic in an urban teaching
hospital. Eye examination included visual acuity and field
testing, slit-lamp examination, intraocular pressure
measurement, dilated ophthalmoscopy, and stereoscopic fundus
photography.
   Half the patients had clinically important eye pathology.
One third of these 205 patients were unaware of having any
eye disease, and of these, 26 percent needed immediate
medical or surgical care. The most common conditions were
glaucoma (26 percent), cataracts (20 percent), and diabetic
retinopathy (12 percent); about a third of affected patients
had more than one condition. Patients who were over age 64,
reported fair or poor vision, were in fair or poor general
health, or had diabetes were at increased risk for eye
disease. Patients with no insurance coverage for eye care
and no recent eye exam (or an exam by an optometrist rather
than an ophthalmologist) were the least likely to be aware
of their eye disease.
   Comment: This single-site study highlights the need for
primary-care patients to receive more consistent screening
for common, treatable eye conditions. --CD Mulrow.
   Citation: Wang F; et al. Undetected eye disease in a primary care clinic
population. Arch Intern Med 1994 Aug 22; 154:1821-8.

SYMPTOM-TRIGGERED TREATMENT FOR {*filter*} WITHDRAWAL.
   Benzodiazepines are effective for treating {*filter*}
withdrawal, but the usual fixed, "round the clock" dosing
schedule may expose patients to excess medication. This
double-blind, controlled trial evaluated a symptom-triggered
regimen in 101 patients admitted to an inpatient
detoxification unit at a Veterans Affairs medical center.
   Patients randomized to the fixed regimen received
chlordiazepoxide four times daily with additional medication
as needed. The symptom-triggered regimen provided
chlordiazepoxide only when signs and symptoms of {*filter*}
withdrawal developed. The severity of {*filter*} withdrawal was
measured by a validated scale based on physiologic signs and
symptoms.
   Compared with patients on the fixed schedule, those on
the symptom-triggered regimen had shorter treatment
durations (median, 9 vs. 68 hours) and received lower doses
of chlordiazepoxide (median, 100 vs. 425 mg). There were no
significant differences between the groups in the severity
of withdrawal symptoms.
   Comment: This study indicates that the round-the-clock
sedation regimens that are often used to treat {*filter*}
withdrawal represent more therapy than needed for many
patients. Symptom-triggered therapy tailored to each
patient's needs can be equally effective with less
medication. --TH Lee.
   Citation: Saitz R; et al. Individualized treatment for {*filter*} withdrawal:
a randomized double-blind controlled trial. JAMA 1994 Aug 17; 272:519-23.

PERINATAL MEASLES AND CROHN'S DISEASE.
   The causes of Crohn's disease and ulcerative colitis
are unknown. The diseases have features in common; one
hypothesis is that both are associated with perinatal
exposure to viral infections. This study examined whether
people born during measles epidemics in Sweden had an
increased risk for Crohn's disease or ulcerative colitis.
   Researchers identified all people with inflammatory bowel
disease who were born in four counties of central Sweden
between 1945 and 1954 and were diagnosed before age 30; 300
had Crohn's disease and 360 had ulcerative colitis (236
extensive, 124 proctitis). There were five measles epidemics
during this period. The number of people with Crohn's
disease who had been born during the three months after the
epidemics peaked significantly exceeded the number expected
statistically (57 vs. 39). In contrast, the observed and
expected numbers were similar for people with ulcerative
colitis (29 vs. 31 for extensive colitis and 13 vs. 16 for
proctitis).
   Comment: This study does not prove that perinatal measles
causes subsequent Crohn's disease, but it provides further
evidence for a relation between the two. --B Jarman.
   Citation: Ekbom A; et al. Perinatal measles infection and subsequent
Crohn's disease. Lancet 1994 Aug 20; 344:508-10.