Delayed improvement of autonomic nervous abnormality after the Maze procedure: time and frequency domain analysis of heart rate variability using 24 hour Holter monitoring

Objective—To analyse heart rate variability in patients with atrial fibrillation after the Maze procedure, to investigate whether the procedure damages the cardiac autonomic fibres supplying the sinus node.
Design and patients—Time and frequency domain analyses of RR variability were performed using 24 hour Holter monitoring one month after surgery in 12 patients with atrial fibrillation who underwent the Maze procedure (Maze group) and in seven patients who underwent cardiac surgery without the Maze procedure (control group). Mean RR intervals (mRR) and the standard deviation of successive RR intervals (SDRR) were determined by time domain analysis, and high frequency (HF), low frequency (LF), and total power (TP) spectral components of RR variability were calculated by frequency domain analysis. Holter monitoring was also performed at six and 12 months after cardiac surgery in the Maze group.
Results—Circadian variation (mean (SD)) in mRR (daytime to night time difference: 119 (60) v 302 (143) ms), SDRR (daytime: 8.4 (3.3) v 37.0 (12.0) ms), TP (daytime: 46.7 (16.0) v 171.8 (30.4) ms), HF (daytime: 19.6 (9.9) v 36.7 (7.1) ms²), and LF/HF (daytime: 0.31 (0.07) v 1.18 (0.46)) was decreased in the Maze group at one month compared with the control group (p < 0.01), but showed improvement at six and 12 months (p < 0.05).
Conclusions—Surgery combined with the Maze procedure markedly suppressed the circadian variation of heart rate over a 24 hour period within one month after surgery, mainly because of damage to the innervation of the sinus node. However, at six and 12 months there was restoration of circadian variation, probably as the result of reinnervation of the sinus node.

Keywords: autonomic nervous system;  heart rate variability;  Maze procedure     

A case of small cell lung carcinoma complicated by Lambert-Eaton myasthenic syndrome]

A 54-year old man was admitted with general fatigue, muscle weakness and dyspnea on effort. Medical examinations led to a diagnosis of small cell lung carcinoma (SCLC) with Lambert-Eaton myasthenic syndrome (LEMS). Marked improvement of SCLC and symptoms of LEMS were recognized twice during chemoradiotherapy. On his third admission, he showed muscle weakness, dysaethesia, and neurodysfunction of the bladder and rectum. We initially considered these symptoms to be due to spinal metastasis because MRI findings showed multiple spinal metastases. However, electoromyogram and nerve conduction study demonstrated that his muscle weakness resulted from LEMS though dysethesia and neurodysfunction of bladder and rectum were caused by spinal metastasis. We believe that it is important to perform electomyogram and nerve conduction studies, not only radiographic findings, to detect the "hidden" symptoms of LEMS.     

A case of anaphylactoid purpura associated with nephrosis followed by pulmonary tuberculosis

A 54-year old man was admitted to our hospital because of high fever, productive cough and purpura in both legs in June 2005. Urinalysis showed microscopic hematuria and proteinuria. Chest radiograph showed consolidation of right upper field. Because acid-fast bacilli and polymerase chain reaction test for Mycobacterium tuberculosis were positive in bronchial lavage fluid, we made a diagnosis of pulmonary tuberculosis, and prescribed antituberculosis therapy with isoniazid, rifampicin, ethambutol and pyrazinamide. In addition, anaphylactoid purpura was diagnosed by skin biopsy. In July 2005, renal function was deteriorated and nephrosis appeared. We treated with corticosteroid in addition to antituberculosis therapy. His symptoms and renal dysfunction improved. We report a rare case of an anaphylactoid purpura following occurence of pulmonary tuberculosis.     

Long-term clinical outcomes of permanent-polymer everolimus-eluting stent implantation following rotational atherectomy for severely calcified de novo coronary lesions: Results of a 22-center study (Tokyo-MD PCI Study)

Background

Long-term clinical outcomes of permanent polymer everolimus-eluting stent (PP-EES) implantation after rotational atherectomy (RA) have not been fully evaluated. We sought to investigate the long-term clinical outcomes of PP-EES implantation after RA and assess the impact of hemodialysis on this treatment strategy.

Infarct Size Limitation by Bradykinin Receptor Activation Is Mediated by the Mitochondrial But Not by the Sarcolemmal KATP Channel

Earlier studies have shown that activation of bradykinin B₂ receptor triggers protein kinase C (PKC)-mediated cardioprotective mechanism in ischemic preconditioning (PC). In the present study, we examined whether the effector in this B₂-receptor triggered pathway of PC is the ATP sensitive potassium (K_ATP) channel in the mitochondria (mito-K_ATP channel) or K_ATP channel in the sarcolemma (sarc-K_ATP channel). Isolated rabbit hearts were perfused with modified Krebs-Henseleit buffer in a Langendorff mode, and regional myocardial ischemia was induced by occluding a left coronary artery for 30 min and then reperfusing for 2 hours. Infarct size was determined by triphenyltetrazolium chloride staining and expressed as a percentage of area at risk (% IS/AR). Infusion of bradykinin (500 nmol/L) for 15 min prior to ischemia significantly reduced % IS/AR from 37.4 ± 2.9 (SE) of the untreated controls to 12.0 ± 3.3%. This protective effect of bradykinin was completely abolished by coinfusion of 5-hydroxydecanoate (5-HD, 50 mol/L), a selective mito-K_ATP channel blocker (% IS/AR = 44.2 ± 6.4). In contrast, a high dose of HMR1098 (20 mol/L), which is a newly developed sarc-K_ATP channel selective blocker with IC₅₀ of 0.6 mol/L, failed to modify the infarct size limitation by preischemic infusion of bradykinin (% IS/AR = 11.7 ± 3.4). Neither 5-HD nor HMR1098 alone modified infarct size (% IS/AR = 37.8 ± 3.8 and 35.1 ± 6.2, respectively). These results suggest that opening of the mito-K_ATP channel but not the sarc-K_ATP channel is involved in infarct size limitation by a mechanism triggered by bradykinin B₂ receptor activation.     

Immunolocalisation of PIVKA-II in paraffin-embedded specimens of hepatocellular carcinoma

Abstract: Aims/Background: Although serum PIVKA-II has been widely used as a tumor marker for hepatocellular carcinoma (HCC), little information is available concerning tissue PIVKA-II, and detection of tissue PIVKA-II in paraffin-embedded tissue specimens of HCC is also considered difficult. Methods: Paraffin-embedded HCC tissues obtained at autopsy from 22 patients were subjected to immunohistochemical staining using the antibody MU-3 (Eisai Co., Ltd.) after microwave antigen retrieval. Results: PIVKA-II was mainly detected in the cytoplasm of HCC cells. The intensity of tissue PIVKA-II staining was not correlated with serum PIVKA-II levels or with the histological differentiation of HCC. However PIVKA-II staining tended to be more intense in tissue from patients with portal tumor thrombus, distant metastases, or a longer duration of HCC. Conclusion: This method of immunohistochemical staining is easy and simple to use and may be helpful for detecting tissue PIVKA-II in paraffin-embedded HCC specimens.     

Identification of quantitative trait loci for cardiac hypertrophy in two different strains of the spontaneously hypertensive rat.

Cardiac hypertrophy and left ventricular hypertrophy are known to be substantially controlled by genetic factors. As an experimental model, we undertook genome-wide screens for cardiac mass in F2 populations bred from the stroke-prone spontaneously hypertensive rats (SHRSP) and normal spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY) of a Japanese colony. Two F2 cohorts were independently produced: F2(SHRSP x WKY) (110 male and 110 female rats) and F2(SHR x WKY) (151 male rats). The ratio of heart weight to body weight (Hw/Bw) was evaluated at 12 months of age in F2(SHRSP x WKY) after salt-loading for 7 months, and at around 15 weeks of age in F2(SHR x WKY) who had been fed a normal rat chow diet. Subsequent to an initial screen with 251 markers in F2(SHRSP x WKY) male progeny, 170 and 161 markers were selected and characterized in F2(SHRSP x WKY) female progeny and F2(SHR x WKY) male progeny, respectively. Markers from four chromosomal regions showed suggestive or significant linkage to Hw/Bw. The strongest and the most consistent linkage was found in the vicinity of D3Mgh16 on rat chromosome (RNO) 3 (a maximal log of the odds score reached 4.0 to 6.6 across the F2 populations studied). In the other three regions on RNO6, RNO10 and RNO13, the degree of linkage was more prominent in either males or females. These data provide solid evidence for a "principal" RNO3 quantitative trait loci regulating Hw/Bw in SHRSP and SHR, and also suggest the possible presence of sexual dimorphism in regard to genetic susceptibility for cardiac hypertrophy.     

Requirement of gp130 signaling for the AGM hematopoiesis

OBJECTIVE: Definitive hematopoiesis starts in the aorta-gonad-mesonephros (AGM) region during mouse development and remarkably expands in the liver at a later stage of ontogeny. gp130 is a signal transducing receptor component shared by all the IL-6 family cytokines, whose gene ablation in mouse results in the significant reduction in the fetal liver hematopoiesis. The present study aims to evaluate the role of gp130 signaling in the fetal mouse AGM hematopoiesis. METHODS AND MATERIALS: Mouse AGM regions from the wild-type and gp130-deficient mice on embryonic day 11.5 were dissociated and cultured with a mixture of cytokines, including one which activates gp130. Wild-type human gp130 and its mutant constructs were introduced into cultured gp130-deficient AGM cells using retrovirus system. To further analyze gp130 downstream signaling, a dominant-negative mutant of STAT3 was also introduced. RESULTS: The gp130 deficiency in the culture of fetal mouse AGM cells resulted in the failure of the expansion of the c-kit(+), Sca-1(+), and lineage markers(-) population. Such failure was rescued by introduction of a wild-type gp130 expression construct but not its mutant constructs having no ability to activate STAT3. In the normal AGM cell culture, introduction of a dominant-negative form of STAT3 in which Y(705) was changed to phenylalanine suppressed the expansion of hematopoietic cell colonies. CONCLUSION: gp130 plays an indispensable role in the expansion of hematopoietic precursor cells in the fetal mouse AGM. In particular, the activation of STAT3 by gp130 is found to be important in this process.     

Salt intake causes B-type natriuretic peptide elevation independently of blood pressure elevation in the general population without hypertension and heart disease

Excessive salt intake causes hypertension and cardiovascular diseases (CVDs). B-type natriuretic peptide (BNP) is synthesized and released from the ventricle, and is a surrogate marker reflecting various CVDs. Moreover, when a slight BNP elevation is shown, it leads to a poor prognosis in the general population. However, the relationship between salt intake and BNP levels in the general population remains unclear, especially in those without hypertension and heart diseases.In this study, we recruited 1404 participants without hypertension and electrocardiogram abnormalities, who received regular annual health check-ups in Japan. Plasma BNP levels were measured, and daily salt intake levels were evaluated using urinary samples. In addition, some clinical parameters were obtained, and the data were cross-sectionally analyzed.The median of plasma BNP levels was 10.50 pg/mL, and daily salt intake was 8.50 ± 1.85 g. When dividing participants into quartiles according to daily salt intake, those with the highest daily salt intake revealed the highest plasma BNP levels. Plasma BNP levels were significantly and positively associated with daily salt intake. Moreover, multiple linear regression analyses revealed that plasma BNP levels showed a significant positive association with daily salt intake levels after adjustments.Plasma BNP levels were significantly and positively associated with daily salt intake after adjustment in the general population. Plasma BNP levels may be a surrogate marker reflecting salt-induced heart diseases.