Page 51 - Coronary hemodynamics in acute myocardial infarction - Matthijs Bax

Microvascular resistance of infarct and noninfarct coronary arteries
flow velocity was measured with a 0.014-inch Doppler wire (FloWire, Jomed, Ulestraten, The Netherlands) distal to the lesion. Special attention was paid to
obtain the best Doppler signal. At least 3 measurements were made each time
and were accepted when the variance was lower than 10%. A bolus of 0.1 mg of nitroglycerin was administered before flow assessment and repeated every 30
minutes. CFVR was determined as the ratio of hyperemic average peak blood
flow velocity induced by adenosine (20 μg intracoronary) to baseline average 3 peak blood flow velocity. Flow velocities, heart rate, and blood pressure
were recorded continuously on videotape (FloMap, Jomed). CFVR was also measured at the end of the procedure in an angiographically normal non-IRA (the largest branch of the left circumflex artery [n = 68] unless there was >30% diameter stenosis, in which case the right coronary artery was used [n = 5]). At follow-up, Doppler flow velocities were assessed at the same position as during angioplasty. Before and after angioplasty and at follow-up, Thrombolysis In Myocardial Infarction flow and myocardial blush were graded11and corrected. Thrombolysis In Myocardial Infarction frame count was measured12offline in IRAs and non-IRAs.
Concomitant medical therapy
Patients were treated with 300 mg of aspirin orally and 5,000 IU of heparin intravenously before the procedure. An additional 2,500 IU of heparin intravenously was administered if the procedure lasted >90 minutes. Treatment with abciximab, during 12 hours, was at the operator’s request. According to the protocol, patients received unfractionated heparin for 48 hours and 100 mg/day of aspirin and 250 mg of ticlopidine 2 times daily or 75 mg/day of clopidogrel for 1 month after stent placement. Captopril was administered within 24 hours after angioplasty and titrated up, if possible, to 25 mg 3 times daily and 50 mg of metoprolol 2 times daily. Statin treatment was started the day after admission irrespective of serum cholesterol values.
Follow-up
At 6 months, all patients were evaluated for major events, which were defined as death from all causes, nonfatal reinfarction (>30 minutes of angina with ST- segment depression or elevation with myocardial enzyme release >2 times the upper limit of normal), repeat angioplasty, or coronary artery bypass graft surgery.
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