Cardiac Sympathetic Dysfunction Correlates With Abnormal Myocardial Contractile Reserve in Dilated Cardiomyopathy Patients

• Published in: Journal of the American College of Cardiology 2005-12, Vol.46 (11), p.2061-2068
• Main Authors: Ohshima, Satoru, Isobe, Satoshi, Izawa, Hideo, Nanasato, Mamoru, Ando, Akitada, Yamada, Akira, Yamada, Kiyoyasu, Kato, Tomoko S., Obata, Koji, Noda, Akiko, Nishizawa, Takao, Kato, Katsuhiko, Nagata, Kohzo, Okumura, Kenji, Murohara, Toyoaki, Yokota, Mitsuhiro
• Format: Article
• Language: English
• Subjects: 3-Iodobenzylguanidine; Aged; Biological and medical sciences; Blood pressure; Cardiac Pacing, Artificial; Cardiology; Cardiology. Vascular system; Cardiomyopathy, Dilated - diagnostic imaging; Cardiomyopathy, Dilated - physiopathology; Catheters; Female; Heart; Heart - innervation; Heart attacks; Hemodynamics; Humans; Male; Medical sciences; Middle Aged; Myocardial Contraction - physiology; Myocarditis. Cardiomyopathies; Norepinephrine - blood; Radionuclide Imaging; Radiopharmaceuticals; Reverse Transcriptase Polymerase Chain Reaction; Rodents; Stroke Volume; Sympathetic Nervous System - physiopathology; Veins & arteries; Ventricular Function, Left - physiology
• ISSN: 0735-1097; 1558-3597
• DOI: 10.1016/j.jacc.2005.08.046

Cardiac Sympathetic Dysfunction Correlates With Abnormal Myocardial Contractile Reserve in Dilated Cardiomyopathy Patients Satoru Ohshima, Satoshi Isobe, Hideo Izawa, Mamoru Nanasato, Akitada Ando, Akira Yamada, Kiyoyasu Yamada, Tomoko Kato, Koji Obata, Akiko Noda, Takao Nishizawa, Katsuhiko Kato, Kohzo Nagata, Kenji Okumura, Toyoaki Murohara, Mitsuhiro Yokota We investigated the relationship between myocardial iodine-123-metaiodobenzylguanidine (123I-MIBG) findings and myocardial contractile reserve in response to atrial pacing stimulation in dilated cardiomyopathy (DCM) patients. A significant correlation was observed between the delayed 123I-MIBG accumulation and the percent change in left ventricular dP/dtmax. The sarcoplasmic reticulum Ca2+-ATPase (SERCA2) messenger ribonucleic acid (mRNA) levels were significantly lower in DCM patients with more severely reduced myocardial 123I-MIBG accumulation than in those with mildly reduced accumulation. Abnormal myocardial 123I-MIBG accumulation is related to an impaired myocardial contractile reserve and down-regulation of SERCA2 mRNA in DCM. Myocardial 123I-MIBG scintigraphy can be useful in noninvasively evaluating myocardial contractile reserve in patients with DCM. We investigated the relationship between iodine-123-metaiodobenzylguanidine (123I-MIBG) findings and myocardial contractile reserve in patients with mild to moderate dilated cardiomyopathy (DCM). Little is known regarding the relationship between cardiac sympathetic nervous function and myocardial contractile reserve in DCM. Twenty-four DCM patients who showed sinus rhythm underwent echocardiography, biventricular catheterization, and myocardial 123I-MIBG scintigraphy. Left ventricular (LV) pressures were measured using a micromanometer-tipped catheter. The myocardial contractile function (LV dP/dtmax) was determined at rest and during atrial pacing. The messenger ribonucleic acid (mRNA) expressions of intracellular Ca2+-regulatory proteins were analyzed by real-time quantitative reverse transcription-polymerase chain reaction. Myocardial 123I-MIBG accumulation was quantified as a heart-mediastinum ratio (HMR). A significant correlation was observed between the delayed 123I-MIBG HMR and the percentage change in LV dP/dtmaxfrom the baseline to the peak or critical heart rate (r = 0.64; p < 0.001). The delayed 123I-MIBG HMR was significantly lower in patients showing a worsening change in LV dP/dtmaxthan in those showing a favorable change (p < 0.