Kenichi Katoh

Prediction of the severity of coronary artery disease by measurement of lipoprotein (a)

BackgroundA number of clinical studies have shown that high serum lipoprotein (a) [Lp(a)] levels are associated with coronary artery disease (CAD). It is, however, unclear whether increased serum concentration of Lp(a) alone is a significant risk factor for CAD. MethodsWe studied 120 consecutive patients who underwent selective coronary angiography: 34 with old myocardial infarction, 47 with angina pectoris, and 39 without ischemic heart disease. ResultsSerum Lp(a) concentrations measured by an enzyme immunoassay method were significantly higher in both the myocardial infarction (mean 23.5 mg/dL, P<0.01) and angina pectoris (22.6 mg/dL, P<0.05) groups than in the no ischemic heart disease group (14.1 mg/dL). On multiple regression analysis with Friesingers severity score (F score) as the criterion variable, the factors that were independently related to F score were Lp(a) (standard regression coefficient [p] = 0.326, P< 0.01), high-density lipoprotein cholesterol (-0.251, P<0.01), and low-density lipoprotein cholesterol (0.225, P<0.01); other coronary risk factors were not related to the score. Serum Lp(a) levels rose as the number of affected arteries (≥75% stenosis) increased (13.3, 21.7, 21.8, and 30.1 mg/dL for zero, one, two, and three affected vessels, respectively). Very similar results were obtained in 78 selected subjects with normal serum cholesterol (<220 mg/dL). ConclusionsWe conclude that Lp(a) is an independent risk factor for CAD and further predicts its severity.

Availability and limitations of thallium-201 myocardial SPECT quantitative analysis: Assessment as daily routine procedure for ischemic heart disease

To determine the availability and limitations of the detection of ischemic lesions by stress thallium-201 myocardial SPECT as the daily routine procedure, we compared and evaluated the detectability of the quantitative analysis (%uptake and washout rate (WR)) and visual evaluation in 104 patients with effort angina and 17 normal subjects.Visual evaluation combined with WR analysis resulted in significantly higher sensitivity (88.0%) but lower specificity (60.2%) than the other methods. The sensitivity by visual evaluation was quite low in multivessel disease (MVD), and in the regions supplied by mild coronary stenosis or by the left circumflex artery. These were markedly improved by combining visual evaluation and WR analysis, but sensitivity in the MVD group was unsatisfactory even with this analytic method in comparison with the single vessel disease group. One of the causes of low sensitivity in the MVD group might be the “true negative”: No induction of the ischemia in the regions of milder stenosis, or the regions supplied by the collateral coronary flow.We therefore conclude that the combination of visual evaluation as a qualitative analysis and WR analysis as a quantitative analysis, is the most useful daily routine procedure as a screening test for detecting ischemia.

Coronary Revascularization in a Patient with Calcified Aorta Using Ventricular Fibrillation without Aortic Cross-clamping.

上行大動脈に高度の石灰化病変がある54歳の女性症例に対して, 上行大動脈にまったく操作を加えずに冠動脈バイパス術を行った. 大腿動脈より送血カニューレを挿入して体外循環を行い, cardioplegia 液を使用せず大動脈非遮断低体温心室細動下に, 両側内胸動脈と右胃大網動脈の3本の動脈グラフトを使用して3枝バイパス術を施行した. 術後は脳合併症など起こすことなく順調に経過した. 上行大動脈の高度石灰化症例に対してはこの aortic no touch technique が安全かつ確実な手術方法と考えられた.