IJBEM, Vol. 5, No. 1, 2003

Studying of the Magnetocardiography Indexes
in CAD Diagnosis

Victor Kozlovsky^a, Mykola Budnyk^b, Leonid Stadnyuk^c, Olga Zahrabova^c

^aStrazhesko Institute for Cardiology, Kyiv, Ukraine
^bGlushkov Institute for Cybernetics, Kyiv, Ukraine
^cKyiv Medical Academy for Pos Graduate Training, Kyiv, Ukraine

Correspondence: M Budnyk, Glushkov Institute for Cybernetics, NAS of Ukraine, P.O. Box 03680, Kyiv-187, Ukraine.
E-mail: d220@public.icyb.kiev.ua , phone +380 44 266 1267, fax +380 44 266 3348

Abstract. Aim of work is to obtain diagnostic criteria for CAD pts with unchanged rest ECG by magnetocardiography (MCG). Data acquisition was performed by single-channel magnetocardiograph according to standard method at the 6X6 grid. Medical analysis was carried out with help of 9 numerical MCG indexes reflecting spatial-temporal structure of magnetic field. It was obtained 6 indexes, which are different via t-Test, having diagnostic value (sensitivity&specificity) for CAD.

Keywords: Magnetocardiography; Magnetic Maps; Non-Invasive Medical Diagnostic; CAD

1. Introduction

MCG is non-invasive and safe method for magnetic field recording, advantage of which consists in the localization of the heart currents. But MCG technique is not intensively introduced in clinic practice due to a number of reasons. From our viewpoint, main reason consists in absence of statistically valid and diagnostically clean numerical indicators, which allow determining certain heart pathology.

From other hand, reliable CAD diagnostics is still actual problem. The reason consists in that rest ECG is normal, EchoCG and MRT is limited by mainly morphological heart structure (but did not directly links with electrophysiology), and various stress-tests can be prone to risks. Last decade considerable efforts are directed toward the studying of MCG to CAD diagnostics [Tavarozzi I et al, 2002], that is why; the purpose of this study is finding of relevant MCG indexes.

2. Material and Methods

86 examined patients were divided into two groups: healthy – 44 persons (19 males, 25 females, 44±14) and 42 CAD pts (32 males, 10 females, 58±10) with unchanged ECG at rest. Additionally, for all pts were conducted clinical examinations, ECG, EchoCG, coronary angiography, bicycle test. MCG observations were performed in Biomagnetic Lab (Institute for Cardiology, Kyiv) by single-channel magnetocardiograph at unshielded environment [Budnyk M et al, 2002].

3. Results and Discussion

The ST interval, reflecting the process of ventricle repolarization, was analyzed with set of 32 maps and numerical indexes are calculated. Among 9 indexes, value of which have been shown previously [Kozlovsky V et al, 2002], we found 6 ones, having a finest clinical significance.

The present study shows 9 indexes are significantly different with level p<0.05. For 6 from which, average sensitivity and specificity are 56% and 87%, respectively. Thus, above indexes have diagnostic value compare to other studies [Tavarozzi I et al, 2002] and can be used for CAD diagnosing.

Acknowledgements

This work has been supported from Science&Technology Center in Ukraine (STCU), grant 2187.

References

Budnyk M, Chaikovsky I. Kozlovsky V, Primin M, Sosnytsky V, Stadnyuk L, Voytovych I. Diagnostic criteria for chronic ishemic heart disease based on registry and analyses of the magnetocardiograms. Institute for Cybernetics, Kyiv, 2002.

Kozlovsky V, Budnyk M, Stadnyuk L, Dmytriyeva T, Voytovych I, Rekovets O, Getman T. Registration and processing of magnetocardiograms for patients with CAD, In proceedings of the 13^th Intern. Conf. on Biomagnetism, 2002, 576-578.

Tavarozzi I, Comani S, Del Gratta C, Di Lusio S, Romani G, Gallina S, Zimarino M, Brisinda D, Fenici r, De Caterina R, Magnetocardiography: current ctatus and perspectives. Part II: Clinical applications, Italian Heart Journal, 2002, 3(3):151-165.