Reversible high-grade atrioventricular block with septal myocardial edema in Lyme carditis.

A 34-year-old road builder was admitted to the authors' emergency department due to progressive dyspnoea that had been present for 6 days. The patient had a history of excessive smoking (60 cigarettes/day). The medical history was otherwise unremarkable. A transient rash had occurred during work 2 weeks previously. The patient could not remember a bite. The electrocardiogram showed 2:1 atrioventricular (AV) block with narrow QRS complexes. D­dimer and C­reactive protein were slightly elevated; all other laboratory findings were within normal range. Echocardiography revealed normal findings. ELISA and western blot analysis confirmed acute Lyme disease. Cardiac magnetic resonance imaging (MRI) disclosed myocardial edema in the interventricular septum. Antibiotic treatment with ceftriaxone was initiated for 2 weeks. The heart block improved to a first degree AV block (PR interval 274 ms) at day 5 of treatment. At discharge, the patient had a normal PR interval of 190 ms. Follow-up cardiac MRI revealed almost complete regression of the cardiac septal edema.

Wide QRS complex tachycardia due to typical atrial flutter with accessory pathway conduction.

A 62-year-old male patient was admitted with regular wide QRS complex tachycardia. After ajmaline administration, the heart rate slowed down disclosing atrial flutter with variable QRS morphologies. Electrocardiography after conversion to sinus rhythm showed narrow QRS complexes. Decremental atrial stimulation during electrophysiological study caused progressive pre-excitation. Spontaneously, typical atrial flutter occurred with pre-excited QRS complexes. Both accessory pathway and atrial flutter were ablated in the same session.

A rare case of narrow QRS tachycardia with "hidden" concealed left-sided accessory pathway.

A 54-year-old-woman with narrow QRS tachycardia (heart rate, 210 beats per minute) was admitted to the authors' hospital. Tachycardia terminated after administration of adenosine. The 12-lead electrocardiogram after conversion to sinus rhythm was unremarkable. During electrophysiological study, tachycardia could be easily induced by programmed atrial stimulation without jump phenomenon. The cycle length was 260 ms. During tachycardia, the atrial activation sequence in the coronary sinus (CS) was distal-to-proximal. However, during decremental ventricular pacing, retrograde conduction showed exclusively proximal-to-distal activation in the CS. What is the underlying mechanism?

Radiofrequency ablation of a concealed left-sided accessory pathway in the mid-coronary sinus after failed conventional ablation attempts.

The case of a 71-year-old female patient with recurrent supraventricular tachycardia is reported. During the initial electrophysiological study, an orthodromic atrioventricular reentrant tachycardia utilizing a concealed left-sided accessory pathway (AP) was induced. Radiofrequency (RF) ablation via a retrograde aortic approach was unsuccessful. A second ablation attempt 6 weeks later via a transseptal approach using the EnSite Precision three-dimensional (3-D) cardiac mapping system and an irrigated-tip RF ablation catheter also failed to ablate the AP. Therefore, mapping in the coronary sinus (CS) was performed. During right ventricular pacing, the earliest retrograde atrial activation was found in the mid-CS. Irrigated-tip RF ablation for 1.8 s at this region successfully ablated the AP permanently. In complicated cases after failed conventional ablation attempts via a transfemoral or transseptal approach, CS ablation is an effective alternative to percutaneous or surgical ablation of epicardial APs. In such cases, electroanatomical mapping systems may be useful in determining the location of the AP and reducing fluoroscopy time. Furthermore, ablation with irrigated-tip RF catheters can improve the treatment success rate due to larger and deeper lesion formation.

Renal denervation with standard radiofrequency ablation catheter is effective in 24-hour ambulatory blood pressure reduction - follow-up at 1/3/6/12 months.

AIMS: To examine the effect of renal denervation (RDN) on 24­h ambulatory blood pressure (ABP) with a standard radiofrequency ablation catheter (RF catheter). METHODS: Seventy-five patients with resistant hypertension received bilateral RDN with an RF catheter (6 RF applications, 1 minute each, 8-12 watts). Seventy patients fulfilled inclusion criteria with mean systolic ABP ≥140 mmHg (mean 165/89) despite treatment with ≥3 antihypertensive drugs (mean 5.9) including a diuretic, and were further analysed for ABP changes. Follow-up at 1/3/6/12 months comprised biochemical evaluations and ABP measurement. At 6/12 months, duplex sonography of the renal arteries was additionally performed. RESULTS: At 1/3/6/12 months we observed a significant reduction in systolic ABP of -15/-17/-18/-15 mmHg (n = 55/53/57/50; non-parametric Friedman test, p < 0.001) and diastolic ABP of -6/-9/-10/-7 mmHg (p < 0.001). Of the patients, 70 %/64 % showed a systolic ABP reduction of ≥10 mmHg, and 77 %/70 % of ≥5 mmHg at 6/12-month follow-up. Two patients (2.7 %) developed renal artery stenosis (>70 %) with subsequent stenting without complications. Logistic regression analysis with systolic ABP reduction ≥10 mmHg at 12 months follow-up as criterion revealed that only the mean baseline systolic ABP was significant, OR = 2.174. CONCLUSIONS: RDN with a standard RF catheter can be used safely to reduce mean ABP in resistant hypertension as shown in long-term follow-up.

[A 22-year-old patient from Ghana with fever and reduced CD4 T-cell count]. / Fieber und erniedrigte CD4-Zellzahl bei einem 22-jährigen Patienten aus Ghana.

A 22-year-old patient from Ghana without relevant co-morbidities was admitted twice with fever of unknown origin and reduced CD4 T-cell count. During the second hospital stay, after prolonged incubation of blood cultures and detection of vegetations on the mitral valve in a transesophageal echocardiogram, infectious endocarditis with Aggregatibacter aphrophilus was diagnosed. Treatment according to European guidelines resulted in resolution of the fever, dissolution of the mitral valve vegetations and recovery of CD4 T-cell count.

[Incessant or recurrent ventricular tachycardia. Indications for emergency ablation]. / Unaufhörliche oder rezidivierende ventrikuläre Tachykardien. Wann ist die Notfallablation indiziert?

Incessant ventricular tachycardia and "electrical storms" are emergencies, requiring urgent action in a close cooperation between critical care physicians and cardiologists. The leading cause of such events is advanced cardiac disease. Besides the patient's history, an ECG and, if applicable, an implantable cardioverter-defibrillator (ICD) interrogation is required for a reliable diagnosis. Further diagnostics include laboratory parameters, an echocardiogram, and possibly a coronary angiography. The medical therapy, consisting of amiodarone and ß-blockers, should immediately be initiated after diagnosis. In the case of failed drug therapy, urgent catheter ablation is indicated. This is a complex procedure, in which the clinical tachycardia or the electrical substrate is modified by using an irrigated catheter. The acute success rate of this life-saving procedure is high. However, there might also be complications due to the required extensive procedures.

Induced expression of lectin-like oxidized ldl receptor-1 in vascular smooth muscle cells following Chlamydia pneumoniae infection and its down-regulation by fluvastatin.

Microorganisms such as Chlamydia pneumoniae have been shown to infect vascular cells and are believed to contribute to vascular inflammation and atherosclerotic plaque development. Plasma levels of oxidized low density lipoprotein (oxLDL) have received considerable attention as potential predictors of prognosis in atherosclerotic diseases. Lectin-like oxidized LDL receptor-1 (LOX-1) is one of the major receptors for oxidized LDL. It was investigated whether C. pneumoniae infection can stimulate expression of LOX-1 in vascular smooth muscle cells. Expression of LOX-1 in VSMC was measured by RT-PCR and immunoblotting following C. pneumoniae infection. To examine the pharmacological effect of a HMG-CoA reductase inhibitor on LOX-1 expression, cells were co-incubated with fluvastatin immediately after infection. A dose and time dependent expression of LOX-1mRNA and protein was found in C. pneumoniae infected SMC. After heat and UV light treatment of the chlamydial inoculum the level of LOX-1 was reduced to that of mock-infected cultures. Furthermore, treatment of infected cells with fluvastatin decreased LOX-1 expression to baseline levels. The up-regulation of LOX-1 induced by C. pneumoniae could lead to continued lipid accumulation in atherosclerotic lesions. Together with the widespread expression of LOX-1, this might contribute to the epidemiologic link between C. pneumoniae infection and atherosclerosis. The effect of lowering the LOX-1 expression by fluvastatin may provide a pharmacological option of limiting oxLDL uptake via its scavenger receptor.

Improvement of the primary success rate of recanalization of chronic total coronary occlusions with the Safe-Cross system after failed conventional wire attempts.

BACKGROUND: In view of the improved long-term patency with drug-eluting stents, the challenge with chronic total coronary occlusion (CTO) remains the low primary success rate. Improved guide wires have increased this rate, but alternative devices may be of additional value. The goal of the present study was to determine the additional benefit of a new penetration device in CTOs after an extensive conventional wire approach. METHODS AND RESULTS: In 148 consecutive patients the recanalization of a CTO of >3 months was attempted. A conventional wire approach was used with recent dedicated recanalization wires, which was successful in 104 patients (70%). If after at least 20 min of fluoroscopic time no crossing of the wire was achieved, the Safe-Cross wire (SC) (Intralumina) was used which enables verification of the intraluminal wire position via optical reflectometry, and crossing of resistent occlusion caps by radiofrequency ablation. Due to severe dissections after the conventional approach, the SC was not used in 10 patients. In 34 patients the SC wire was applied, leading to successful lesion crossing in 14 patients (41%). Thus, the primary success rate was improved from 70.2% to 79.7%. No periprocedural major adverse events were observed with the SC wire. The successful attempts with the SC wire were predominantly in blunt occlusions. All patients with successful wire passage could be treated with one or more stents. CONCLUSIONS: In a real world cohort of patients with CTO, the SC wire could increase the primary success rate after failed extensive conventional wire attempt. In these worst case patients the SC success rate was 41%. This new wire appears to have additional potential in failures of a conventional wire approach.

Interferon-beta induction by Chlamydia pneumoniae in human smooth muscle cells.

Clinical studies have suggested a causal or contributory role of Chlamydia pneumoniae infection in asthma and atherosclerosis. The activation of synthetic functions of smooth muscle cells (SMC) including the production of cytokines and growth factors plays a major role in the formation of fibrous atherosclerotic plaques as well as in structural remodelling of the airway wall in chronic asthma. In this study we demonstrated that C. pneumoniae induced the production of low levels of interferon (IFN)-beta in bronchial and vascular SMC when infected cells were treated with tumour necrosis factor-alpha (TNF-alpha). IFN-beta production was analysed by reverse transcription-PCR and enzyme-linked immunosorbent assay. The upregulation of IFN-beta was paralleled by an increase in mRNA levels of interferon regulatory factor-1 and interferon-stimulated gene factor 3gamma, two transcription factors activating the expression of the IFN-beta gene. In addition, C. pneumoniae infection enhanced the mRNA level of indoleamine 2,3-dioxygenase, an IFN-inducible factor mediating the restriction of intracellular chlamydial growth, in TNF-alpha-stimulated SMC. C. pneumoniae-induced IFN-beta production by SMC may modulate inflammation and tissue remodelling during respiratory and vascular infection.

Vasoactive intestinal peptide and epidermal growth factor: co-mitogens or inhibitors of keratinocyte proliferation in vitro?

Vasoactive intestinal peptide (VIP) is a neuropeptide with a broad range of biological activities in various tissues. Interactions of VIP and epidermal growth factor (EGF) are of particular interest for dermatology. They may be either co-mitogenic or inhibitory. HaCaT keratinocytes cultivated under serum-free conditions in vitro have been used to investigate the interactions of VIP and EGF. EGF was found to induce cell growth, whereas preincubation with VIP inhibited EGF-induced proliferation in a dose-dependent manner. Maximum growth inhibition was 46% (p < 0.01) at a VIP concentration of 10(-7) M. EGF-induced growth is mediated by tyrosine kinase (TK). Therefore we studied the effect of VIP on TK activity. Cells were incubated with VIP (10(-13)-10(-7) M) for 48 h and stimulated with EGF at a final concentration of 500 ng/ml. SDS-PAGE and Western blot with the antibody RC20H against TK were performed. We found a dose dependent decrease of EGF receptor TK activity. At VIP concentration of 10(-7) M a residual TK activity of 65% was detected. To investigate the possibly involved signal transduction pathways, we performed inhibition experiments with wortmannin, pertussis toxin, 2'5'diacylglycerol and adenosine-3':5'-mono-phosphorothioate. However, none of the inhibitors was effective in abolishing growth inhibition by VIP. VIP was shown to be growth inhibitory for human keratinocytes. The data suggest that EGF receptor TK is involved in signal transduction of VIP. Thus TK activity is a possible common target of both EGF- and VIP-induced cellular responses.

Keratinocyte growth inhibition by streptococcal proteins.

M proteins are receptor proteins and one of the virulence factors of streptococci. M proteins seem to play a role in inflammatory skin disorders such as psoriasis. It is however unknown whether M proteins have a direct influence on proliferative activity of human keratinocytes. In the present study human HaCaT keratinocytes were exposed to M proteins (M1, M3, M5, M12) and the proliferative and proinflammatory response was analyzed. We found a dose-dependent inhibition of keratinocyte proliferation with crude extract of strain M3 4/55. Following affinity chromatography we found inhibitory activity for keratinocyte proliferation with a maximum of 80% at 10-8 M in the M protein. Additionally tested M1 protein preparation showed an inhibitory activity of 55% whereas other M preparations (5 and 12) did not show any effect. In supernatants from HaCaT cultures IL-1alpha, IL-1beta, IL-6, IL-8, TNFalpha and ICAM-1 were measured by ELISA. The levels of IL-8 were high and TNFalpha was upregulated, whereas ICAM-1 was decreased from around 20 ng/ml to almost zero. In contrast to the streptococcal-derived M3 protein preparation the recombinant M3 did not interfere with the proliferation of HaCaT cells. Because neither recombinant M3 protein nor M3 protein purified by ion exchange chromatography on a Q-resource column had any antiproliferative activity on keratinocytes we suggest, that a component different from M3 protein was responsible.