石井 潤一

Background It has been proposed that 0.5-mm-slice multislice computed tomography (MSCT) is a noninvasive tool for the detection of atherosclerotic plaque, but the validity of such an assessinent has not been demonstrated by an invasive investigation. The present study was performed to compare the 0.5-mm-slice NISCT density of plaques with intravascular ultrasound (IVUS) findings. Methods and Results Atherosclerotic plaques were characterized in 37 consecutive patients undergoing percutaneous interventions. Based on the IVUS echogenecity, the plaques were classified as soft (n= 18), fibrous (n= 40) or calcified (n=40). In these 98 plaques, 0.5-mm-slice MSCT plaque density was calculated in 443 regions-of-interest, including 331 lesional foci and 112 luminal cross-sections, and represented as Hounsfield units (HU). MSCT density of the 3 types of plaque was 11 +/- 12 HU, 78 +/- 21 HU, and 516 +/- 198 HU respectively. Computed tomography density of the (contrast-filled) lumen was 258 +/- 43HU. There were statistically highly significant differences in the densitometric characteristics among the 4 groups (soft, fibrous, calcified plaque and lumen) by nonparametric Kruskal-Wallis test (p < 0.0001). Conclusions The IVUS-based coronary plaque configuration can be accurately identified by 0.5-mm slice MSCT. Noninvasive assessment of plaque characterization will ensure emphasis on the vessel wall beyond the vascular lumen.

急性期の脳神経外科的処置後の患者における頭痛の有無や頭蓋内圧(Intracranial Pressure:ICP)の変動に対する精神性発汗量と温熱性発汗量の推移について調査した.測定結果から,まず,ICPおよび血圧の変動と精神性発汗量の変動は相関することがわかった.次に,頭痛があり,収縮期血圧がやや高くICPの亢進が推測される状態では,精神性発汗量が温熱性発汗量よりも有意に多く検出された.対照として同一症例で頭痛がなく,収縮期血圧がほぼ正常の状態では精神性発汗と温熱性発汗はほとんど検出されなかった.一方,ICPが亢進している場合のみならず,薬剤を用いてICPを降下させた場合においても精神性発汗量が温熱性発汗量よりも有意に多く検出された.急性期の脳神経外科的処置後の患者に対する看護では,ICP亢進の早期発見は非常に重要である.今回の結果から,精神性発汗量を測定することでICPの推移を間接的であるが,非侵襲的および簡易的に連続モニタリングすることができる可能性があることが示唆された(著者抄録)

BACKGROUND: Heart-type fatty acid-binding protein (H-FABP) is proposed as an early biomarker for acute myocardial infarction (AMI), but its prognostic value is unclear in acute coronary syndrome (ACS). We evaluated the prognostic value of the H-FABP concentration relative to cardiac troponin T (cTnT) in the early hours of ACS. METHODS: Serum concentrations of H-FABP and cTnT were measured on admission in 328 consecutive patients hospitalized for ACS within 6 h after the onset of chest pain [AMI, 241 (73.5%) patients; ST-segment elevation myocardial infarction, 154 (47.0%) patients; and emergent coronary angiography within 24 h after admission, 287 (87.5%) patients]. Cardiac events, which were defined as cardiac death or subsequent nonfatal AMI, were monitored for 6 months after admission. RESULTS: During the 6-month follow-up period, there were 25 cardiac events, including 15 cardiac deaths and 10 subsequent nonfatal AMIs. Stepwise multivariate analyses including clinical, electrocardiographic, and biochemical variables revealed that increased H-FABP (above the median of 9.8 microg/L), but not increased cTnT (above the median of 0.02 microg/L), was independently associated with cardiac events in all patients [relative risk (RR) = 8.96; P = 0.0004], the subgroup of patients with ST-segment elevation myocardial infarction (RR = 11.3; P = 0.02), and the subgroup of patients with unstable angina and non-ST-segment elevation myocardial infarction (RR = 8.31; P = 0.007). The area under the ROC curve was higher for H-FABP than for cTnT (0.711 vs 0.578; P = 0.08), suggesting that H-FABP concentrations have a greater predictive capacity for cardiac events than cTnT. CONCLUSION: Serum H-FABP is a potential independent predictor of cardiac events within 6 months of patient admission and may provide prognostic information superior to cTnT in the early hours of ACS.

BACKGROUND: Recent studies have suggested that cardiac troponin T (cTnT) and troponin I may detect ongoing myocardial damage involved in the progression of chronic heart failure (CHF). This study was prospectively designed to examine whether the combination of cTnT, a marker for ongoing myocardial damage, and B-type natriuretic peptide (BNP), a marker for left ventricular overload, would effectively stratify patients with CHF after initiation of treatment. METHODS: We measured serum cTnT, plasma BNP, and left ventricular ejection fraction (LVEF) on admission for worsening CHF [New York Heart Association (NYHA) functional class III to IV] and 2 months after initiation of treatment to stabilize CHF (n = 100; mean age, 68 years). RESULTS: Mean (SD) concentrations of cTnT [0.023 (0.066) vs 0.063 (0.20) micro g/L] and BNP [249 (276) vs 753 (598) ng/L], percentage increased cTnT (>0.01 micro g/L; 35% vs 60%), NYHA functional class [2.5 (0.6) vs 3.5 (5)], and LVEF [43 (13)% vs 36 (12)%] were significantly (P <0.01) improved 2 months after treatment compared with admission. During a mean follow-up of 391 days, there were 44 cardiac events, including 12 cardiac deaths and 32 readmissions for worsening CHF. On a stepwise Cox regression analysis, increased cTnT and BNP were independent predictors of cardiac events (P <0.001). cTnT >0.01 micro g/L and/or BNP >160 ng/L 2 months after initiation of treatment were associated with increased cardiac mortality and morbidity rates. CONCLUSION: The combination of cTnT and BNP measurements after initiation of treatment may be highly effective for risk stratification in patients with CHF.

Apical hypertrophic cardiomyopathy has been divided into two entities: apical asymmetric septal hypertrophy (apical ASH) and apical symmetric hypertrophy (AH). The latter differs clinically from hypertrophic cardiomyopathy (HCM) with ASH, and it is unclear whether AH represents a distinct subtype of HCM. In the present study, the presence or absence and the extent of cardiac muscle cell disorganization, a histologic characteristic of HCM, were compared in patients with AH (n = 10) and ASH (n = 29) in whom cardiac biopsy specimens were obtained from the left ventricular apex and interventricular septum. Disorganization was graded as (1+) in only 1 patient in the AH group and (-) in the remaining 9. In contrast, in the ASH group disorganization was graded as (1+) in 15 patients, (2+) in 7, (3+) in 3, and (-) in only 4 (P < 0.0001). Thus, it was observed that in AH disorganization is virtually absent or at most limited to a very narrow area. It is concluded from a histological stand point as well that the type of apical hypertrophic cardiomyopathy showing apical symmetric hypertrophy differs from usual HCM.

We prospectively evaluated whether the combination of admission measurements of a marker for myocardial cell injury and a marker for left ventricular overload would effectively risk stratify patients with acutely decompensated heart failure. We measured serum concentrations of cardiac troponin T (cTnT) using a second-generation assay, as well as serum cardiac troponin I (cTnI) and plasma atrial and brain natriuretic peptide (BNP) concentrations on admission in 98 consecutive patients hospitalized for worsening chronic heart failure (mean age 69 years; 5 patients were in New York Heart Association functional class II, 35 were in class III, and 58 patients were in class IV). During a mean follow-up period of 451 days, there were 37 cardiac events, including 21 cardiac deaths (14 in-hospital deaths) and 16 readmissions for worsening heart failure. In a stepwise Cox regression analysis, including these biochemical markers, age, sex, functional class, and left ventricular ejection fraction, cTnT, and BNP were found to be significantly independent predictors of both cardiac death (p <0.05) and cardiac events (p <0.01). A cTnT >0.033 microg/L and/or a BNP >440 pg/ml on admission was correlated with an incremental increase in in-hospital cardiac mortality, overall cardiac mortality, and cardiac event rate. Kaplan-Meier analysis revealed that this combination could reliably stratify the patients into low-, intermediate-, and high-risk groups for cardiac events. Measuring the combination of admission concentrations of cTnT and BNP may be a highly effective means of risk stratification of patients hospitalized for worsening chronic heart failure.

Objective: To determine the usefulness of vectorcardiography (VCG) in assessing myocardial infarct size. Methods: The correlation of spatial and scalar parameters of VCG with the percent defect volume (% DV) of thallium myocardial single photon emission computed tomography (SPECT) was investigated in 63 patients with first-onset myocardial infarction (MI). VCG parameters included: (1) spatial parameters: magnitude, azimuth and elevation of the maximal vector, vectors at 20 ms and 30 ms, and (2) scalar parameters: amplitudes of 20 ms and 30 ms vectors at X, Y, and Z scalar leads abbreviated as X20, Y20, Z20, X30, Y30 and Z30, respectively. Results: For anteroseptal MI, the azimuth of 30 ms vector and Z20 showed a significant correlation with % DV (r=0.572, P&lt 0.05 and r=0.832, P&lt 0.001) while in anteroseptal MI with involvement of lateral wall, the azimuth of 30 ms vector and X30 were correlated with %DV significantly (r=0.775, and 4=0.780, P&lt 0.01). For inferior and inferoposterior MI, the elevation of 30 ms vector and Y30 were correlated well with %DV (r=0.871, P&lt 0.01, r=0.928, P&lt 0.001 for inferior MI and r=0.678, P&lt 0.01, r=0.760, P&lt 0.001 for inferoposterior MI). Conclusion: VCG parameters, especially scalar parameters, can be used to evaluate myocardial infarct size easily and non-invasively with remarkable accuracy.