The PACIFIC Trial

	March 7, 1999 - Percutaneous myocardial 
revascularization, or PMR, looks like a promising
treatment for patients with severe coronary artery 
disease (CAD) which does not respond to drug 
therapy. For the growing number of patients
who can't have any more angioplasty or bypass 
surgery, PMR may be a way of treating ischemia. 
Dr. Stephen Oesterle presents the 6-month results 
of the Potential Angina Class Improvement From 
Intramyocardial Channels (PACIFIC) Trial.
	221 patients with class 3-4 angina were 
randomized to PMR plus drug therapy or to aggressive
anti-anginal drug therapy only. Patients not allowed 
into this trial included those with an EF less than 
30%, Q-wave heart attack within the last 3 months, 
non-Q-wave heart attack within the last 6 weeks, 
unstable angina within the last 2 weeks, or severe 
aortic blockage.
	Patients getting PMR had 10 to 15 channels 
made via an ECG-gated YAG laser inserted through an 
artery in their groin. The patients were followed for 
12 months. Primary endpoints were angina score and 
exercise tolerance.
	There were no significant differences in the 
original tests of the 2 groups. The average age was 62.
86% were male. 48% of the PMR group had diabetes. 41% of the 
control group had diabetes. High blood pressure was present 
in 67% of the PMR group and 75% of the control group. 
Previous heart attack had happened in 65% of the PMR group 
and 68% of control patients. Previous invasive treatments 
had been done in 86% of the PMR patients and 96% of controls.
	RESULTS: At 3 month follow-up, 70% of the PMR patients 
had improved to class 2 or better angina, while less than 15% 
of control patients had improved to class 2 or better angina. 
46% of the patients getting PMR had an improvement of at 
least 2 angina classes, versus 6% of patients treated with 
drug therapy alone. These results were unchanged at 6 month 
follow-up.
	Exercise ability also improved in the PMR group. At 3 
months, the PMR group had about a 25% increase in treadmill
exercise time. At 6 months, the PMR group exercised 30% longer 
compared to pre-study level. Control patients had a 5% 
improvement in exercise duration at 3 and 6 months.
	After 6 months of follow-up, 8 deaths (7%) occurred 
in the PMR group, and 2 deaths (2%) in the control group. No 
deaths, heart attacks or strokes occurred during the procedure 
itself. One patient developed complete heart block and 
required permanent pacemaker implantation.
	CONCLUSIONS: After reviewing the 6-month follow-up,
it appears that PMR is safe. Patients assigned to PMR had 
a definite improvement in angina scores and also an improved
treadmill exercise time. We await the 12-month follow-up data.
PMR may be promising for managing people with angina that 
does not respond to drug therapy and who are not suitable 
candidates for more angioplasty or bypass surgery.
	Although not a primary endpoint, there was a 6-month 
mortality of 7% in PMR patients vs 2% in patients treated 
with drug therapy alone. Given that the patients in this study 
would have a poor outcome due to their severity of disease, 
future trials will assess the safety and risk:benefit ratio
of this therapy.