This Article Full Text Full Text (PDF) Submit a related Letter to the Editor Purchase Article View Shopping Cart Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Bengel, F. M. Articles by Schwaiger, M. Search for Related Content PubMed PubMed Citation Articles by Bengel, F. M. Articles by Schwaiger, M. Pubmed/NCBI databases Compound via MeSH Substance via MeSH Hazardous Substances DB LEVOTHYROXINE

Effect of Thyroid Hormones on Cardiac Function, Geometry, and Oxidative Metabolism Assessed Noninvasively by Positron Emission Tomography and Magnetic Resonance Imaging

Nuklearmedizinische Klinik und Poliklinik der Technischen Universität München, 81675 Munich, Germany

Address all correspondence and requests for reprints to: Frank M. Bengel, M.D., Nuklearmedizinische Klinik und Poliklinik, Technische Universität München, Klinikum rechts der Isar, Ismaninger Strasse 22, 81675 Munich, Germany. E-mail: frank.bengel{at}lrz.tu-muenchen.de

Thyroid hormones influence cardiac performance directly and indirectly via changes in peripheral circulation. Little, however, is known about the effect on myocardial oxidative metabolism and its relation to cardiac function and geometry. Patients with a history of thyroidectomy for thyroid cancer present a unique model to investigate the cardiac effects of hypothyroidism. Ten patients without heart disease were investigated in the hypothyroid state and again 4–6 weeks later under euthyroid conditions. Myocardial oxidative metabolism was measured by positron emission tomography with [¹¹C]acetate and the clearance constant k(mono). Cine magnetic resonance imaging was applied to determine left ventricular geometry. A stroke work index (SWI = stroke volume x systolic blood pressure/ventricular mass) was calculated. Then, to estimate myocardial efficiency, a work metabolic index [WMI = SWI x heart rate/k(mono)] was obtained. Compared to hormone replacement, systemic vascular resistance and left ventricular mass were significantly higher in hypothyroidism. Ejection fraction and SWI were significantly lower. Despite an additional reduction of k(mono), the WMI was significantly lower, too. In summary, cardiac oxygen consumption is reduced in hypothyroidism. This reduction is associated with increased peripheral resistance and reduced contractility. Estimates of cardiac work are more severely suppressed than those of oxidative metabolism, suggesting decreased efficiency. These findings may provide an explanation for development or worsening of heart failure in hypothyroid patients with preexisting heart disease.

This article has been cited by other articles:

				L. H Duntas and B. Biondi Short-term hypothyroidism after Levothyroxine-withdrawal in patients with differentiated thyroid cancer: clinical and quality of life consequences Eur. J. Endocrinol., January 1, 2007; 156(1): 13 - 19. [Abstract] [Full Text] [PDF]

				Y.-D. Tang, J. A. Kuzman, S. Said, B. E. Anderson, X. Wang, and A. M. Gerdes Low Thyroid Function Leads to Cardiac Atrophy With Chamber Dilatation, Impaired Myocardial Blood Flow, Loss of Arterioles, and Severe Systolic Dysfunction Circulation, November 15, 2005; 112(20): 3122 - 3130. [Abstract] [Full Text] [PDF]

				G. J. Kahaly and W. H. Dillmann Thyroid Hormone Action in the Heart Endocr. Rev., August 1, 2005; 26(5): 704 - 728. [Abstract] [Full Text] [PDF]

				A. Ripoli, A. Pingitore, B. Favilli, A. Bottoni, S. Turchi, N. F. Osman, D. De Marchi, M. Lombardi, A. L'Abbate, and G. Iervasi Does subclinical hypothyroidism affect cardiac pump performance?: Evidence from a magnetic resonance imaging study J. Am. Coll. Cardiol., February 1, 2005; 45(3): 439 - 445. [Abstract] [Full Text] [PDF]

				S. Fazio, E. A. Palmieri, G. Lombardi, and B. Biondi Effects of Thyroid Hormone on the Cardiovascular System Recent Prog. Horm. Res., January 1, 2004; 59(1): 31 - 50. [Abstract] [Full Text]

				J. Sorensen, E. Stahle, B. Langstrom, G. Frostfeldt, G. Wikstrom, and G. Hedenstierna Simple and Accurate Assessment of Forward Cardiac Output by Use of 1-11C-Acetate PET Verified in a Pig Model J. Nucl. Med., July 1, 2003; 44(7): 1176 - 1183. [Abstract] [Full Text] [PDF]

				A. R. Cappola and P. W. Ladenson Hypothyroidism and Atherosclerosis J. Clin. Endocrinol. Metab., June 1, 2003; 88(6): 2438 - 2444. [Full Text] [PDF]

				B. Biondi, E. A. Palmieri, L. Pagano, M. Klain, G. Scherillo, M. Salvatore, G. Fenzi, G. Lombardi, and S. Fazio Cardiovascular Safety of Acute Recombinant Human Thyrotropin Administration to Patients Monitored for Differentiated Thyroid Cancer J. Clin. Endocrinol. Metab., January 1, 2003; 88(1): 211 - 214. [Abstract] [Full Text] [PDF]

				A. Oatridge, M. L. Barnard, B. K. Puri, S. D. Taylor-Robinson, J. V. Hajnal, N. Saeed, and G. M. Bydder Changes in Brain Size with Treatment in Patients with Hyper- or Hypothyroidism AJNR Am. J. Neuroradiol., October 1, 2002; 23(9): 1539 - 1544. [Abstract] [Full Text] [PDF]

				G. Vitale, M. Galderisi, G. A. Lupoli, A. Celentano, I. Pietropaolo, N. Parenti, O. de Divitiis, and G. Lupoli Left Ventricular Myocardial Impairment in Subclinical Hypothyroidism Assessed by a New Ultrasound Tool: Pulsed Tissue Doppler J. Clin. Endocrinol. Metab., September 1, 2002; 87(9): 4350 - 4355. [Abstract] [Full Text] [PDF]

				E. Fommei and G. Iervasi The Role of Thyroid Hormone in Blood Pressure Homeostasis: Evidence from Short-Term Hypothyroidism in Humans J. Clin. Endocrinol. Metab., May 1, 2002; 87(5): 1996 - 2000. [Abstract] [Full Text] [PDF]

				B. Biondi, E. A. Palmieri, G. Lombardi, and S. Fazio Effects of Thyroid Hormone on Cardiac Function - The Relative Importance of Heart Rate, Loading Conditions, and Myocardial Contractility in the Regulation of Cardiac Performance in Human Hyperthyroidism J. Clin. Endocrinol. Metab., March 1, 2002; 87(3): 968 - 974. [Abstract] [Full Text] [PDF]

				F. M. Bengel, P. Ueberfuhr, N. Schiepel, S. G. Nekolla, B. Reichart, and M. Schwaiger Myocardial Efficiency and Sympathetic Reinnervation After Orthotopic Heart Transplantation : A Noninvasive Study With Positron Emission Tomography Circulation, April 10, 2001; 103(14): 1881 - 1886. [Abstract] [Full Text] [PDF]

				I. Klein and K. Ojamaa Thyroid Hormone : Targeting the Vascular Smooth Muscle Cell Circ. Res., February 16, 2001; 88(3): 260 - 261. [Full Text] [PDF]

				I. Klein and K. Ojamaa Thyroid Hormone and the Cardiovascular System N. Engl. J. Med., February 15, 2001; 344(7): 501 - 509. [Full Text] [PDF]

				I. Klein and K. Ojamaa Editorial: Thyroid Hormone--Targeting the Heart Endocrinology, January 1, 2001; 142(1): 11 - 12. [Full Text] [PDF]