ABSTRACT
Background: It is reported that 20 to 30% of patients are not responders to this treatment (Cardiac Resynchronization Therapy). The reasoning in this merely theoretical paper shows the plausible danger that can be brought by measurements apparatus, in the occurrence the CRT especially when it is sophisticated. Objective: In Physical Cardiochemistry field our overall purpose is to bring a contribution to heart health. It is needful to draw attention for caregivers and manufacturers, especially with respect to the magnetism these apparatuses may exhibit. Methods: The Observation and documentary research are used. It is recalled hereby successively energy metabolism in healthy cardiomyocyte, adaptive energy metabolism of a hypertrophied and insufficient heart, cardiac resynchronization therapy and energy metabolism of the cardiomyocyte with its potential effects on both glucose oxidation and fatty acids oxidation. Results: It is shown a plausible interaction between oxygen magnetic field, paramagnetic by nature, and pacemaker and/or defibrillator electromagnetic field according to the sacral principle of “like dissolves like” with all evil consequences on patients. Conclusion: It will be necessary to evaluate later not only the behavior of the various energetic substrates of a hypertrophied heart as a function of the variation of the magnetic field strength but also the content of the probable substances produced in the presence of a magnetic field and with a potentially harmful effect on cardiac function. Convinced technology has its setbacks, the pacemakers and/or defibrillators manufacturers are invited to a greater rigor, greater caution and sustained care in building these devices. In next publication study of a case (CRT-D), where the diabetes has been observed, will be outlined.
ABSTRACT
PURPOSE: To evaluate the NMR relaxation properties of newly developed high performance paramagnetic. MATERIALS AND METHODS: 4-aminomethylcyclohexane carboxylic acid (0.63 g, 4 mmol) was mixed with the suspension solution of DMF (15 mL) and DTPA-bis-anhydride (0.71 g, 2 mmol) to synthesize the ligand. The ligand was then mixed with Gd2O3 (0.18 g, 0.5 mmol) to synthesize Gd-chelate. For the measurement of magnetic relaxivity of paramagnetic compounds, the compounds were diluted to 1mM and then the relaxation times were measured at 1.5T(64 MHz). Inversion-recovery pulse sequence was employed for T1 relaxation measurement and CPMG(Carr-Purcell-Meiboon-Gill) pulse sequence was employed for T2 relaxation measurement. Using MATLAB(Version 7.1) program, T1 magnetic relaxation map, R1 map, T2 magnetic relaxation map and R2 map were developed to represent magnetic relaxation time and magnetic relaxivity as image. RESULTS: Compared to R1=4.9 mM(-1) sec(-1) and R2= 4.8 mM(-1) sec(-1) of Omniscan (Gadodiamide), which is commercially available paramagnetic MR agent, R1 of SUK090(Gd-C32H74N5O24) was 12.46 mM(-1) sec(-1) and R1 of SUK091(Gd-C34H78N5O24) was 12.77 mM(-1) sec(-1). However, R1 of SUK092(Gd-C30H56N5O17) was decreased to 2.09 mM(-1) sec(-1). In case of R2, SUK090(Gd-C32H74N5O24) was 8.76 mM(-1) sec(-1) and SUK091(Gd-C34H78N5O24) was 7.60 mM(-1) sec(-1) whereas SUK092(Gd-C30H56N5O17) CONCLUSION: Among three new paramagnetic complexes, SUK090(Gd-C32H74N5O24) and SUK091(Gd-C34H78N5O24) showed higher T1, T2 magnetic relaxation rates than that of commercially available paramagnetic MR agent and thus expected to have more contrast enhancement effect.
Subject(s)
RelaxationABSTRACT
PURPOSE: To evaluate the NMR relaxation properties and imaging characteristics of tissue-specificity for a newly developed macromolecular MR agent. MATERIALS AND METHODS: Phthalocyanine (PC) was chelated with paramagnetic ion, Mn. 2.01g(5.2 mmol) of Phthalocyanine was mixed with 0.37g (1.4 mmol) of Mn chloride at 310 degrees C for 36 hours and then purified by chromatography (CHC13/CH3OH 98/2 v/v, Rf, 0.76) to obtain 1.04g (46%) of MnPC (molecular weight = 2000d), The T1/T2 relaxivity of MnPC was measured in 1.5T(64 MHz) MR using 0.1 mM MnPC. The MR image characteristics of MnPC was evaluated using spin-echo (TR/TE = 500/14 msec) and gradient-echo (FLASH) (TR/TE = 80/4 msec, flip angle = 60) techniques in 1.5T MR scanner. The images of rabbit liver were obtained every 10 minutes up to 4 hours. To study the effect of concentration on image, 20 mM, 50 mM, 100 mM of MnPC were tested. RESULTS: The relaxivities of MnPC at 1.5T (64MHz) were R1 = 7.28 mM-1S-1, R2 = 55.56 mM-1S-1. Compared to the values of Gd-DTPA (R1[= 4.8 mM-1S-1), R2[= 5.2 mM-1S-1]), both T1/T2 relaxivities of MnPC were higher than those of Gd-DTPA. For both of SE and FLASH techniques, the contrast enhancement reached maximum at 10 minutes after bolus injection and the enhancement continued for more than 2 hours. When compared with small molecular weight liver agents such as Gd-EOB-DTPA, Gd-BOPTA and MnDPDP, MnPC was characterized by more prolonged enhancement time. The time course of MR images also revealed biliary excretion of MnPC. CONCLUSION: We developed a new macromolecular MR agent, MnPC. The relaxivities of MnPC were higher than those of small molecular weight Gd-chelate. Hepatic uptake and biliary excretion of MnPC suggests that this agent is a new liver-specific MR agent.