countries during a 6 month follow up. Countries with high
intervention rates had higher stroke rates but lower rates of
recurrent angina and readmission for unstable angina.
The FRISC II study,^1 comparing early invasive and conservative
strategies, together with the effect of placebo-controlled long term
low molecular weight heparin (dalteparin), showed a reduction in
death and myocardial infarction in the invasive group (9.4% vs
12.1% in the non-invasive group at 6 months, p = 0.031).
Symptoms of angina and readmission were also halved by the
invasive strategy. The greatest benefit was seen in high risk
patients, in whom potentially beneficial treatments are often denied
in routine clinical practice. By 6 months, 37% of the non-invasive
group had crossed over to the invasive strategy. Although there was
a higher event rate initially in the invasive group, associated with
revascularisation, the event rate subsequently fell and the hazard
curves crossed after 4 weeks. Thereafter, the event rate was
consistently lower in the invasive group. Invasive treatment
provided the greatest advantages in older patients, men, patients
with a longer duration of angina, chest pain at rest and ST segment
depression.
The favourable results of FRISC II reflect not only modern
revascularisation technologies but probably also the intended
delay prior to angiography and intervention. Patients in the
invasive arm were initially stabilised medically, with the aim to
perform all invasive procedures within seven days.
The consensus of opinion has thus changed and, where
facilities permit, intensive medical therapy followed by angiog-
raphy with a view to revascularisation is the preferred option for
patients with unstable coronary artery disease.
RReeffeerreenncceess
1 Fragmin and Fast Revascularisation during InStability in Coronary
artery disease (FRISC II) Investigators. Invasive compared with non-
invasive treatment in unstable coronary-artery disease: FRISC II
prospective randomised multicentre study. Lancet1999; 335544 : 708–15.
2 Anderson HV, Cannon CP, Stone PH et al. One-year results of the
Thrombolysis in Myocardial Infarction (TIMI) IIIB clinical trial: a
randomised comparison of tissue-type plasminogen activator versus
placebo and early invasive versus early conservative strategies in
unstable angina and non-Q wave myocardial infarction. J Am Coll
Cardiol1995; 2266 : 1643–50.
3 Boden WE, O’Rourke RA, Crawford MH et al. for the Veterans Affairs
Non-Q Wave Infarction Strategies in Hospital (VANQWISH) Trial