Correspondence
JACC Vol. 55, No. 6, 2010 February 9, 2010:608–11
*Marc Dewey, MD, PhD *Charité–Universitätsmedizin Berlin Institut für Radiologie Charitéplatz 1 10117 Berlin Germany E-mail:
[email protected] doi:10.1016/j.jacc.2009.09.040 REFERENCES
1. Anderson JD, Epstein FH, Meyer CH, et al. Multifactorial determinants of functional capacity in peripheral arterial disease: uncoupling of calf muscle perfusion and metabolism. J Am Coll Cardiol 2009;54:628 –35. 2. Dewey M. Comprehensive assessment of peripheral artery disease using magnetic resonance imaging, angiography, and spectroscopy. J Am Coll Cardiol 2009;54:636 –7. 3. Price JF, Mowbray PI, Lee AJ, Rumley A, Lowe GD, Fowkes FG. Relationship between smoking and cardiovascular risk factors in the development of peripheral arterial disease and coronary artery disease: Edinburgh Artery Study. Eur Heart J 1999;20:344 –53. 4. Dijk JM, Wangge G, Graaf Y, Bots ML, Grobbee DE, Algra A. Hemoglobin and atherosclerosis in patients with manifest arterial disease. The SMART study. Atherosclerosis 2006;188:444 –9. 5. Braunwald E. Epilogue: what do clinicians expect from imagers? J Am Coll Cardiol 2006;47:C101–3.
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microvascular angina. He points to the need for future research on possible mechanisms. One such mechanism, which seems to have been overlooked, is the contribution of pressure and time during diastole when the left ventricle can be perfused (2). This is reduced in older women with stiffened arteries, particularly when the left ventricle is hypertrophied (3). Indeed, a decrease in diastolic duration from 33 to 27 s/min can have the same effect as an increase in coronary stenosis from 40% to 90% (4). Perhaps the continuing dilemma is created by our assumption that reduced coronary flow is always due to arterial narrowing. It seems to be appropriate to look beyond the microvascular disease that is presumed but never demonstrated. *Michael F. O’Rourke, MD, DSc Wilmer W. Nichols, PhD *St Vincent’s Clinic 438 Victoria Street, Suite 810 Darlinghurst, Sydney NSW 2010 Australia E-mail:
[email protected] doi:10.1016/j.jacc.2009.10.029 Please note: Dr. O’Rourke is a founding director of AtCor Medical Pty Ltd., Sydney, Australia.
REFERENCES
Microvascular Angina or “Vis a Tergo” Cannon (1) has drawn attention to the high prevalence of ischemiatype chest pain with normal coronary angiograms in older women in the CASS (Coronary Artery Surgery Study) and WISE (Women’s Ischemia Syndrome Evaluation) studies, and referred to this as
1. Cannon R. Microvascular angina and the continuing dilemma of chest pain with normal coronary arteries. J Am Coll Cardiol 2009;54:877– 85. 2. Gregg D, Fischer LC. Blood supply to the heart. In: Handbook of Physiology. Washington, DC: Physiological Society, 1963:1517– 84. 3. O’Rourke MF. How stiffening of the aorta and elastic arteries leads to compromised coronary flow. Heart 2008;94:690 –1. 4. Ferro G, Duilio C, Spinelli L, Liucci GA, Mazza F, Indolfi C. Relation between diastolic perfusion time and coronary artery stenosis during stress induced coronary ischemia. Circulation 1995;92:342–7.
