ABSTRACT
<p><b>BACKGROUND</b>In-stent restenosis (ISR) has become one of the most challenging problems in patients with coronary heart disease. At present, using non-invasive methods to assess ISR is a hot topic. In this investigation we attempted to explore the potential of magnetocardiography (MCG) in diagnosis of in-stent restenosis.</p><p><b>METHODS</b>MCG was analyzed in 52 patients with coronary artery disease for three times: before stenting, one month and 7 months after successful intracoronary stenting.</p><p><b>RESULTS</b>The average classification of total maps (ACTM) and the ratio of abnormal maps (RAM) were lower in 1 month after intracoronary stenting compared with that obtained before stent planting (2.91 vs 2.52, 65.74% vs 42.80%, P < 0.01), while complex ventricular excitation index (CVEI) increased from -42.63 to -20.05 (P < 0.01). In ISR subgroup (n = 16), RAM decreased in 1 month after intracoronary stenting compared to it before stenting (68.99% vs 45.26%, P < 0.05). ACTM increased in 7 months compared to that obtained in 1 month after stenting (3.15 vs 2.51, P < 0.05). According to the ROC curve, ACTM showed its unique diagnostic value in restenosis patients. The sensitivity and specificity of ACTM were 80.0%, 69.40%, respectively. Its positive predictive value and negative predictive value were 54.6% and 88.5%, respectively.</p><p><b>CONCLUSIONS</b>After successful intracoronary stenting, most parameters of MCG were improved. ACTM was of prognostic value in diagnosing ISR.</p>
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Angioplasty, Balloon, Coronary , Coronary Artery Disease , Diagnosis , Coronary Restenosis , Diagnosis , Magnetocardiography , Methods , StentsABSTRACT
<p><b>OBJECTIVE</b>To investigate the magnetocardiography (MCG) changes in coronary artery disease (CAD) patients with normal or unspecific changes in resting electrocardiogram (ECG).</p><p><b>METHODS</b>MCG mapping was performed by MCG-7 (MaGIC, Magiscan GmbH) installed in an unshielded room. All patients underwent ECG and coronary angiogram examinations and patients with normal or unspecified ECG changes and coronary artery narrowing > or = 70% in at least 1-vessel were defined as CAD group (n = 120). Patients with normal coronary angiogram served as control (n = 82). Four parameters: ACTM (average classification of total maps), RAM (ratio of abnormal maps), CVEI (complex ventricular excitation index) and R-max/T-max ratio, were analyzed in CAD and control groups.</p><p><b>RESULTS</b>RAM (62% vs. 35%) and ACTM (2.62 +/- 0.98 vs. 2.29 +/- 0.90, P < 0.05) were significantly higher in CAD group than in control group. CVEI was found in abnormal zone (-100 - 0) in CAD group while in normal zone (0 - 100) in control group. The ratio of Rmax/Tmax in CAD group was also significantly higher in CAD group than in control group (6.41 +/- 3.29 vs. 4.10 +/- 2.00, P < 0.01). ROC curve analysis indicates that RAM, CVEI and Rmax/Tmax ratio were helpful parameters for CAD diagnosis and the diagnostic sensitivity was 67.1%, 65.9% and 64.3%; the specificity was 65.1%, 68.3% and 68.3% respectively.</p><p><b>CONCLUSION</b>MCG was a useful tool for diagnosing chronic myocardium ischemia in CAD patients with normal or unspecific changes resting ECG.</p>