Detection of U wave activity in healthy volunteers by high-resolution magnetocardiography

INTRODUCTION

The purpose of our study was to prove the existence of the U wave using magnetocardiograms (MCGs).

METHODS

The 31-channel MCGs of 25 healthy volunteers were recorded. The onset of the U wave was defined by newly developed spatial correlation analysis; and the end, by different approaches.

RESULTS

A U wave could be proved in all volunteers. In 10 volunteers (heart rate, 57 +/- 19 beats/min) in whom the U wave was found to be separated from the following P wave, the U wave's end could be determined as a threshold value (U wave duration, 310 +/- 24 milliseconds). In 15 volunteers (heart rate, 70 +/- 38 beats/min), the end of the U waves was concealed by a continuous transition of the U waves into the following P waves.

CONCLUSIONS

The U wave seems to be a regular phenomenon and has a distinct spatiotemporal assembly.

Effect of intra-aortic balloon pump support on microcirculation during high-risk percutaneous intervention

Background: Intra-aortic balloon counter-pulsation (IABP) is recommended for hemodynamic support in cardiogenic shock. In addition, it can be applied during high-risk percutaneous interventions (PCI). While IABP support improves microflow in cardiogenic shock, its effect in hemodynamically stable patients is still unclear. We, therefore, sought to evaluate the effect of IABP treatment on microflow in hemodynamically stable patients undergoing elective high-risk PCI. Methods: In six patients with >" xbd="892" xhg="869" ybd="1310" yhg="1284"/>50% left main stenosis, microflow was evaluated according to current guidelines, using side-stream dark-field microscopy, visualizing microcirculatory vessels without using fluorescent dyes. Microflow was analyzed separately for each vessel category (diameter: 10-25µm and 26-50µm), using a semiquantitative system (0= no flow; 1= intermittent flow; 2= sluggish flow; 3= continuous flow) by a trained investigator. Steady state recordings and additional recordings twenty seconds after discontinuation of the electively implanted IABP were acquired. Results: Microflow in vessel categories 10-25µm and 26-50µm increased in this group of hemodynamically stable patients on use of IABP. Microflow decreased from 2.73±0.39 (p=0.052; 26-50µm: 2.88±0.20, p=0.008) to 2.22±0.23 (2.18±0.45) after stopping the IABP and increased to 2.90±0.14 (p=0.009; 2.85±0.28, p=0.009) after restart of the IABP. Conclusions: Circulatory support with IABP increases microcirculatory flow in the smallest vessels of the sublingual mucosa. Our data support the hypothesis that intra-aortic balloon counter-pulsation increases coronary and microvascular perfusion, thus, improving microcirculation even in hemodynamically stable patients. The use of IABP may increase safety of complex PCI and decrease the risk of deleterious complications.

An unusual case of progressive shock and highly elevated procalcitonin level

A 21-year-old man with signs and symptoms of rapidly progressive shock was admitted to the intensive care unit for treatment of suspected sepsis. Levels of inflammatory markers (including procalcitonin) were highly elevated, but no obvious focus of infection was apparent. Initial sepsis therapy included administration of broad-spectrum antibiotics, vasoconstrictors, and drotrecogin alfa. Cultures of blood, sputum, and urine showed no growth, and no viruses were detected. The random (no stimulation with corticotropin) cortisol level at admission was less than 25 nmol/L. Assays for autoantibodies to the adrenal cortex were strongly positive and confirmed the diagnosis of adrenal failure caused by Addison disease. After initiation of steroid therapy, the patient fully recovered. Although increased procalcitonin levels are considered a reliable and specific indicator of severe generalized infections and bacterial sepsis, elevated procalcitonin levels cannot be relied on when trying to differentiate between addisonian crisis and septic shock.

Churg-strauss syndrome presenting with cardiac mass and right ventricular obstruction

A 57-year-old woman presenting with asthma, hypereosinophilia, and generalized unspecific symptoms was diagnosed with Churg-Strauss syndrome. Echocardiography revealed a cardiac mass obliterating the right ventricle and severely impaired left ventricular function, which were caused by endomyocardial fibrosis. Cortisone and cyclophosphamide therapy resulted in amelioration of left ventricular function and significant size reduction of the right ventricular mass.

Stent-based release of a selective PDGF-receptor blocker from the bis-indolylmethanon class inhibits restenosis in the rabbit animal model

Long-term success of modern therapies for myocardial ischemia is limited by restenosis, with proliferation and migration of vascular smooth muscle cells (VSMC) as key events. Since findings in recent years indicate, that the Platelet Derived Growth Factor (PDGF) is an important selective factor in mitogenic and motogenic pathways of VSMC, different concepts for reducing restenosis by inhibiting PDGF signaling have been investigated, with local delivery of small receptor kinase inhibitors looking most promising. We tested the stent-based delivery of the PDGF-receptor inhibitor D-65495, a bis(1H-2-indolyl)methanone, in the rabbit iliac artery model of restenosis. New Zealand white rabbits underwent balloon dilation of iliac arteries for implantation of D-65495-coated or non-coated (solvent, either DMSO or 90%THF / 10% DMSO) coronary stents. After 4 weeks stents were removed and neointima formation in medial and proximal/ distal stent sections was histomorphometrically and immunohistochemically analyzed. Arteries with D-65495 eluting stents showed an up to 50% reduced restenosis compared to control stents. Also, the neointimal area was reduced, but there were no significant differences in injury score. Importantly, endothelialization was similar for control stents as well as for D-65495-coated stents, suggesting absence of a general cytostatic effect of the inhibitor. The impact of D-65495 on PDGF-receptor signaling in the vessel wall was indirectly assessed by immunohistochemical staining for activated protein kinase Akt, and PCNA as a proliferation marker and revealed some reduction for the inhibitor-treated vessels. In conclusion, the application of D-65495 caused a significant decrease in neointima formation, further supporting the concept of using locally released PDGF-receptor kinase inhibitors as anti-restenotic agents.

Transvenous closure of patent foramen ovale: preliminary results with a new self-expanding nitinol wire mesh in a Swine model

Objectives. The transvascular closure of patent foramen ovale (PFO) with self-expanding devices carries the risk of left atrial thrombus formation related to material protruding into the left atrium. Thus, we developed a novel device with flat left atrial disc geometry. We evaluated feasibility, handling, and biocompatibility in a porcine animal model. Methods. Implantation of an Occlutech Figulla PFO device was performed in 10 mini pigs using fluoroscopy and intra-cardiac ultrasound after transseptal puncture of the interatrial septum. Angiographic follow-up was performed after six and twelve weeks. Results. Implantation was successful in 100%. There were no further implant related complications. One procedure related death occurred, as one animal died of ventricular tachycardia due to mispunture of the interatrial septum. Angiographic studies showed no residual shunt during follow-up. Histopathological evaluation could demonstrate partial neoendothelialization after 6 weeks with completion after 12 weeks. The devices were incorporated into connective tissue containing fibro muscular cells. An only mild inflammatory reaction was detected locally related to the polyester fibers. Conclusion. In terms of feasibility and handling, the new device does not seem to be inferior to other presently used implantation systems. Good biocompatibility was demonstrated with rapid and complete neoendothelialization.

Association of waist circumference, traditional cardiovascular risk factors, and stromal-derived factor-1 in adolescents

BACKGROUND

Overweight and the metabolic syndrome (MS) represent dramatically increasing problems in children and adolescents. Waist circumference (WC) is an important factor to determine MS. So far, WC is a predictor of blood pressure, high-density lipoprotein (HDL), insulin concentration, and visceral fat in adolescents. We investigated whether WC and body mass index standard deviation score (BMI-SDS) are predictors of adiponectin, stromal-derived factor (SDF-1), and soluble E-selectin (sE-selectin) as parameters for beginning insulin resistance and endothelial damage.

METHODS

Seventy-nine male Caucasian adolescents were studied, aged 13-17 yr. Thirty-eight (48%) of them had a WC above 90th age percentile. All participants were enrolled in one consultation, recording various parameters and collecting one blood sample.

RESULTS

Differences in systolic blood pressure, HDL, high sensitive C-reactive protein, and hemoglobin A1c could be found between groups above or below the 90th WC percentile. Linear regression analysis revealed that WC and BMI-SDS predict traditional risk factors, as well as reduced adiponectin, lower SDF-1, and higher sE-selectin levels. Multiple linear regression analyses show that SDF-1 is in closest correlation to WC and BMI-SDS.

CONCLUSIONS

WC and BMI-SDS predict various alterations of traditional and new cardiovascular risk factors. SDF-1 might be a new marker for diagnosis of obesity-related diseases and help understand pathophysiologic mechanisms.

Hepatocyte growth factor is elevated in obese adolescents

Hepatocyte growth factor (HGF) is a pleiotropic factor with angiogenic and mitogenic effects and has been linked to vascular diseases. It is elevated in obese adults.

AIM

To investigate whether HGF levels are altered in obese adolescents and whether they correlate with anthropometric measurements of obesity.

METHODS

Seventy-nine male adolescents were enrolled. Forty-eight percent were overweight. Various parameters were recorded at one visit, including BMI and waist circumference, and blood samples were taken. HGF was determined by ELISA.

RESULTS

Overweight adolescents have higher plasma levels of HGF (1,099.8 +/- 416.7 pg/ml) than controls (883.2 +/- 218.7 pg/ml) (p = 0.008). HGF levels correlated with BMI and waist circumference. HGF correlated closely with high sensitive C-reactive protein.

CONCLUSIONS

We demonstrated elevated HGF levels in obese adolescents. We speculate that HGF is a possible link between obesity in early life and related comorbidities.

Differential number of CD34+, CD133+ and CD34+/CD133+ cells in peripheral blood of patients with congestive heart failure

BACKGROUND

Endothelial progenitor cells (EPC) which are characterised by the simulateous expression of CD34, CD133 and vascular endothelial growth receptor 2 (VEGF 2) are involved in the pathophysiology of congestive heart failure (CHF) and their number and function is reduced in CHF. But so far our knowledge about the number of circulating hematopoietic stem/ progenitor cells (CPC) expressing the early hematopoietic marker CD133 and CD34 in CHF is spares and therefore we determined their number and correlated them with New York Heart Association (NYHA) functional class.

METHODS

CD34 and CD133 surface expression was quantified by flow cytometry in the peripheral venous blood of 41 healthy adults and 101 patients with various degrees of CHF.

RESULTS

CD34+, CD133+ and CD34+/CD133+ cells correlated inversely with age. Both the number of CD34+ and of CD34+/CD133+ cells inversely correlated with NYHA functional class. The number of CD133+ cells was not affected by NYHA class. Furthermore the number of CD133+ cells did not differ between control and CHF patients.

CONCLUSION

In CHF the release of CD34+, CD133+ and CD34+/CD133+ cells from the bone marrow seems to be regulated differently. Modulating the releasing process in CHF may be a tool in CHF treatment.

Cardiotrophin-1 induces intercellular adhesion molecule-1 expression by nuclear factor kappaB activation in human umbilical vein endothelial cells

BACKGROUND

In addition to elevated concentrations of cytokines, patients with congestive heart failure (CHF) show endothelial dysfunction and increased plasma concentrations of adhesion molecules like intercellular adhesion molecule-1 (ICAM-1). Furthermore, the concentration of cardiotrophin-1 (CT-1)--a cytokine of the interleukin-6 superfamily--is increased in CHF. We tested the hypothesis whether CT-1 is able to induce ICAM-1 in human umbilical vein endothelial cells (HUVEC). Furthermore we examined the signalling mechanisms of CT-1 mediated ICAM-1 expression.

METHODS

Confluent layers of HUVEC were incubated with increasing concentrations of CT-1 (5 to 100 ng/ml) for different periods. ICAM-1 mRNA was determined by real-time polymerase chain reaction (PCR) and ICAM-1 surface expression by fluorescence-activated cell sorter (FACS) analysis and soluble ICAM-1 (sICAM-1) in the culture supernatant by enzyme linked immunosorbent assay (ELISA). To clarify the signalling pathway of CT-1 induced ICAM-1 expression we used various inhibitors of possible signal transducing molecules, electromobility shift assay (EMSA) and Western blot analysis.

RESULTS

CT-1 induced ICAM-1 mRNA (1.8 +/- 0.8 fold increase compared to unstimulated cells after 6 hours) and protein (1.4 +/- 0.2 fold increase compared to unstimulated cells after 48 hours) in HUVEC in a time- and concentration-dependent manner. EMSA experiments show that CT-1 causes nuclear factor (NF) kappaB activation. Because parthenolide could inhibit CT-1 induced ICAM-1 expression NFkappaB activation is required in this pathway. CT-1 did not activate extracellular signal regulated kinases (ERK), c-Jun N-terminal kinase (JNK) and p38.

CONCLUSION

CT-1 is able to induce ICAM-1 in endothelial cells by NFkappaB activation. These results may explain in part elevated ICAM-1 concentrations in patients with CHF and endothelial dysfunction.

First use of a novel plug-and-play percutaneous circulatory assist device for high-risk coronary angioplasty

OBJECTIVES

Novel circulatory assist devices provide hemodynamic stability in high risk coronary interventions. They ensure sufficient organ perfusion during transfer in case of procedural failure or cardiogenic arrest. We describe the first human use of a novel plug-and-play circulatory assist device for high risk coronary angioplasty.

METHODS

An 84 year old lady suffered syncope with complex fracture of the left forearm. Her syncope was related to a subtotal stenosis of the left main coronary artery associated with an acute myocardial infarction. Additional risk factors were previous cardiac surgery, pulmonary disease, diabetes mellitus, and renal insufficiency. Coronary angiography revealed stenosis of both coronary ostia. The emergency assist device LIFEBRIDGE was connected with the patient's circulation by percutaneous cannulation (15F and 17F) of the femoral artery and vein.

RESULTS

Stent implantation was performed in both coronary ostia by Judkin's technique. The cannulas were removed two hours after the intervention by local compression. Osteosynthesis of the left radius and ulna was performed five days later under regional anesthesia. The patient was discharged without any complains on day 10.

CONCLUSION

This case illustrates the safe and easy use of a novel plug-and-play percutaneous circulatory assist device for high risk interventions. It may be recommended for use in emergency situations.

[Therapy of cardiogenic shock after myocardial infarction]

The therapy of infarct related cardiogenic shock should primarily focus on fastest possible revascularization. In addition, rapid restoration of sufficient organ perfusion pressure is recommended for the prevention of a multi-organ dysfunction syndrome (MODS). This can be achieved by mechanical circulatory assist devices as well as individual catecholamine therapy. Since assist devices require specially trained physicians, their use is limited to specialized cardiac care centers. However, future technologies such as portable heart-lung-machines may help to further improve transfer to specialized centers and therapy of shock patients.