Imaging With a Radio Tracer to Guide VT Ablations

Three Dimension Neuron Imaging Using 123I-metaiodobenzylguanidine Single Photon Emission Computed Tomography to Guide Ventricular Tachycardia Ablations

Some patients are at risk for life-threatening fast heart rates. These can frequently be treated by using a catheter inside the heart to burn away the cells that create the fast heart rates. The purpose of this study is to image the nerves inside the heart of those patients. The investigators want to find out if abnormalities in the nervous system in the heart can help the physician to find the area that needs to be burnt away.

Ventricular tachycardia is the next frontier in cardiology. Patients that have scar in the heart (for example after heart attacks) are at an increased risk of developing ventricular tachycardia. In these patients ventricular tachycardia represents an electrical wave front that circulates in the heart muscle using the scar in the heart. An increasing number of patients with ventricular tachycardia require cauterization (burning away) of the tissue to treat this life-threatening condition. The goal of this cauterization or ablation is to destroy "highways of surviving tissue" inside the scar, that allow ventricular tachycardia to exist. However, this can be very lengthy procedure (>5 hours) that has only a moderate success in the long run. Therefore, new treatment approaches are needed to make this procedure better. The purpose of this study is to assess if radio tracers showing the nerve distribution in the heart (cardiac innervation) can be used in addition to the current technology ("voltage mapping") to identify the area that needs to be ablated (burnt away) to treat life-threatening fast heart rates (ventricular tachycardia) Certain patterns of nerve distribution in the heart (sympathetic cardiac innervation) have been shown to predict outcome for different heart diseases, like heart transplant, coronary artery disease, heart failure, arrhythmias. One substance that allows visualization of the cardiac innervation is 123I-metaiodobenzylguanidine (123I-MIBG), which could provide additional information to understand and treat ventricular tachycardia.

FDA Approved for use in Cancer patients. This use is Off Label. For the imaging study, an activity of 370 MBq (10 mCi) 123I-mIBG (GE Healthcare) will be administered intravenously, and a 10-minute planar image of the anterior thorax (128_128 matrix) will be acquired beginning 15 minutes after tracer injection.

Comparison of the Percentage of Patients With Scar in Each Segment as Determined by MIBG SPECT Versus Electroanatomic at Baseline

Scar Measurement on both MIBG 3D map and electroanatomic scare defined as bipolar voltage <0.5mV using Standard 17-segment American Heart Association areas.

MIBG/SPECT imaging 6 months after ablation. 123I-metaiodobenzylguanidine: For the imaging study, an activity of 370 MBq (10 mCi) 123I-mIBG (GE Healthcare) was administered intravenously, and a 10-minute planar image of the anterior thorax (128_128 matrix) was acquired beginning 15 minutes after tracer injection.

Inclusion Criteria: Patients with ventricular arrhythmias requiring VT Ablation Patients must be 18 years of age or older Patient must be able to sign consent form Patient must be willing to come back for the 6 month visit for additional study procedures Exclusion Criteria: Patient under 18 years old Inability to sign consent Pregnant Women

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Klein T, Abdulghani M, Smith M, Huang R, Asoglu R, Remo BF, Turgeman A, Mesubi O, Sidhu S, Synowski S, Saliaris A, See V, Shorofsky S, Chen W, Dilsizian V, Dickfeld T. Three-dimensional 123I-meta-iodobenzylguanidine cardiac innervation maps to assess substrate and successful ablation sites for ventricular tachycardia: feasibility study for a novel paradigm of innervation imaging. Circ Arrhythm Electrophysiol. 2015 Jun;8(3):583-91. doi: 10.1161/CIRCEP.114.002105. Epub 2015 Feb 23.