Page 154 - Coronary hemodynamics in acute myocardial infarction - Matthijs Bax

Chapter 9
Methods
Between April 1997 and August 2000, 98 consecutive patients with a first anterior wall STEMI treated by primary PCI were enrolled in the study, for whom the initial results have been reported previously.2,11 All patients were treated in the Amsterdam University Medical Centres – location AMC, a large tertiary referral centre in Amsterdam, The Netherlands.
Anterior STEMI was defined as chest pain lasting >30 min in the presence of persistent ST-segment elevation in ≥2 precordial leads. Primary PCI was performed within 6 h after the onset of symptoms according to standard clinical practice, with provisional bare metal stent implantation. Major exclusion criteria comprised prior anterior wall myocardial infarction, acute left-side heart failure (Killip class >II), prior coronary artery bypass grafting, known left ventricular ejection fraction of <40%, left ventricular hypertrophy, absence of thoracic windows for echocardiography, three-vessel coronary artery disease, Thrombolysis In Myocardial Infarction (TIMI) grade 2 or 3 flow at initial angiography before PCI, or unsuccessful PCI defined as TIMI grade 0 or 1 flow or >50% residual stenosis in the infarct-related artery after PCI. The study protocol was approved by the local ethics committee and all patients gave informed consent.
Cardiac catheterization and periprocedural measurements
Five to 10 minutes after successful reperfusion, intracoronary blood flow velocity was measured in the infarct related artery using a 0.014-inch sensor equipped guide wire (Philips/Volcano, Rancho Cordova, California, USA). Additionally, measurements were performed in an angiographic normal non-culprit coronary artery, defined as a coronary artery with <30% diameter stenosis on visual estimation. Non-culprit vessel measurements were performed in the left circumflex coronary artery, unless a stenosis of >30% was present, in which case the right coronary artery was used. At one-week and six-month follow-up, 64 and 65 respectively patients underwent repeat angiography with assessment of intracoronary Doppler flow velocity, of which the initial results have been reported previously.2,11 The flow diagram in Figure 1 shows the number of patients included in the analysis at each time frame. Hyperaemia was induced by an intracoronary bolus of adenosine (40 μg). Before and after
152