Magnetic resonance assessment of the substrate for inducible ventricular tachycardia in nonischemic cardiomyopathy

• Published in: Circulation (New York, N.Y.) Vol. 112; no. 18; pp. 2821 - 2825
• Main Authors: NAZARIAN, Saman, BLUEMKE, David A, WEISS, Robert G, BERGER, Ronald D, LIMA, Joao A. C, HALPERIN, Henry R, LARDO, Albert C, ZVIMAN, Menekhem M, WATKINS, Stanley P, DICKFELD, Timm L, MEININGER, Glenn R, ROGUIN, Ariel, CALKINS, Hugh, TOMASELLI, Gordon F
• Format: Journal Article
• Language: English
• Published: Hagerstown, MD Lippincott Williams & Wilkins 01.11.2005
• Subjects: Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Biological and medical sciences; Blood and lymphatic vessels; Cardiology. Vascular system; Cardiomyopathies - pathology; Cardiovascular system; Death, Sudden, Cardiac; Diseases of the peripheral vessels. Diseases of the vena cava. Miscellaneous; Emergency and intensive care: renal failure. Dialysis management; Humans; Image Processing, Computer-Assisted; Intensive care medicine; Investigative techniques, diagnostic techniques (general aspects); Magnetic Resonance Imaging - methods; Medical sciences; Myocardium - pathology; Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques; Ventricular Dysfunction, Left - pathology; magnetic resonance imaging; Arrhythmia; Cardiomyopathy; Heart disease; Magnetic resonance; Electrophysiology; Cardiovascular disease; Ventricular tachycardia; Myocardial disease; Nuclear magnetic resonance imaging; tachyarrhythmias
• ISSN: 0009-7322; 1524-4539
• DOI: 10.1161/circulationaha.105.549659

Patients with left ventricular dysfunction have an elevated risk of sudden cardiac death. However, the substrate for ventricular arrhythmia in patients with nonischemic cardiomyopathy remains poorly understood. We hypothesized that the distribution of scar identified by MRI is predictive of inducible ventricular tachycardia. Short-axis cine steady-state free-precession and postcontrast inversion-recovery gradient-echo MRI sequences were obtained before electrophysiological study in 26 patients with nonischemic cardiomyopathy. Left ventricular ejection fraction was measured from end-diastolic and end-systolic cine images. The transmural extent of scar as a percentage of wall thickness (percent scar transmurality) in each of 12 radial sectors per slice was calculated in all myocardial slices. The percentages of sectors with 1% to 25%, 26% to 50%, 51% to 75%, and 76% to 100% scar transmurality were determined for each patient. Predominance of scar distribution involving 26% to 75% of wall thickness was significantly predictive of inducible ventricular tachycardia and remained independently predictive in the multivariable model after adjustment for left ventricular ejection fraction (odds ratio, 9.125; P=0.020). MR assessment of scar distribution can identify the substrate for inducible ventricular tachycardia and may identify high-risk patients with nonischemic cardiomyopathy currently missed by ejection fraction criteria.