High density lipoprotein changes in patients with microvascular angina.

We have read with great interest the recently published patients with microvascular angina than in the control paper by Miwa et al. on HDL abnormalities observed in subjects (p,0.05), implying an increase in larger HDL patients with variant angina [1]. The authors noticed that particles. Interestingly, the HDL particles appeared to be high HDL cholesterol /ApoA1 levels associated with low larger in patients with microvascular angina as compared HDL cholesterol and ApoA1 levels were characteristic in to controls both in the smoking and in the non smoking patients with variant angina, in whose HDL particles were subpopulations. large, cholesterol-rich and possibly malfunctioning. Since Thus, despite the absence of lower HDL cholesterol similar to variant angina altered endothelial-mediated levels, patients with microvascular angina, as well as vasomotion of coronary arteries is also observed in the patients with CAD, exhibit larger HDL particles, which, microvasculature of patients with microvascular angina along with the other lipid derangements observed in this [2,3], such HDL abnormalities could have also played a population, could contribute to the existing functional role in its pathogenesis. Recently we have studied the lipid abnormalities. profile of patients with microvascular angina in comparison with patients with coronary artery disease (CAD) and normal subjects [4]. By contrast to the findings References observed in patients with variant angina, HDL cholesterol and ApoA1 levels in microvascular angina patients did not [1] Miwa K, Yoshida N, Nakagawa K, Inoue H. High-density lipoprotein particles are large in patients with variant angina. Cardiovasc Res differ from those observed in control subjects, although the 1998;37:729–737. levels of these parameters in both groups were significantly [2] Maseri A, Crea F, Kaski JC, Crake T. Mechanism of angina pectoris higher than those in the CAD patients. However, the HDL in syndrome X. J Am Coll Cardiol 1991;17:499–506. cholesterol /ApoA1 molar ratio was significantly higher in [3] Egashira K, Inou T, Hirooka Y, Yamada A, Urabe Y, Takeshita A. both groups of patients compared to the control population Evidence of impaired endothelium-dependent coronary vasodilation in patients with angina pectoris and normal coronary angiograms. N [21.961.2 in microvascular angina patients and 22.161.3 Engl J Med 1993;328:1659–1664. in CAD patients vs 20.761.8 in the control group, p,0.05 [4] Tselepis AD, Elisaf M, Goudevenos J, Tselegaridis Th, Bairaktari E, for both comparisons], while the slope of the regression Siamopoulos KC, Sideris D. Lipid profile in patients with miline comparing HDL cholesterol and ApoA1 was greater in crovascular angina. Eur J Clin Invest 1996;26:1150–1155.