Comparison of infection and complication rates associated with transvenous vs. subcutaneous defibrillators in patients with stage 4 chronic kidney disease: a multicenter long-term retrospective follow-up.

Background: Patients with progressive chronic kidney disease (CKD) are at higher risk of infections and complications from cardiac implantable electronic devices (CIED). In patients with a primary or secondary prophylactic indication, implantable cardiac defibrillators (ICD) can prevent sudden cardiac deaths (SCD). We retrospectively compared transvenous-ICD (TV-ICD) and intermuscularly implanted subcutaneous-ICD (S-ICD) associated infections and complication rates together with hospitalizations in recipients with stage 4 kidney disease. Methods: We retrospectively analyzed 70 patients from six German centers with stage 4 CKD who received either a prophylactic TV-ICD with a single right ventricular lead, 49 patients, or a S-ICD, 21 patients. Follow-Ups (FU) were performed bi-annually. Results: The TV-ICD patients were significantly older. This group had more patients with a history of atrial arrhythmias and more were prescribed anti-arrhythmic medication compared with the S-ICD group. There were no significant differences for other baseline characteristics. The median and interquartile range of FU durations were 55.2 (57.6-69.3) months. During FU, patients with a TV-ICD system experienced significantly more device associated infections (n = 8, 16.3% vs. n = 0; p < 0.05), device-associated complications (n = 13, 26.5% vs. n = 1, 4.8%; p < 0.05) and device associated hospitalizations (n = 10, 20.4% vs. n = 1, 4.8%; p < 0.05). Conclusion: In this long-term FU of patients with stage 4 CKD and an indication for a prophylactic ICD, the S-ICD was associated with significantly fewer device associated infections, complications and hospitalizations compared with TV-ICDs.

Subcutaneous cardioverter defibrillator implanted intermuscularly in patients with end-stage renal disease requiring hemodialysis: 5-year follow-up.

BACKGROUND: The aim of the present study was to evaluate the long-term safety and effectiveness of the subcutaneous implantable cardioverter defibrillator (S-ICD) when implanted intermuscularly in patients with end-stage renal disease and hemodialysis. METHODS: This study is a retrospective analysis of 21 consecutive patients implanted with S-ICDs at three experienced centers in Germany with comorbid renal insufficiency requiring hemodialysis, as well as being at risk of sudden cardiac death. The S-ICD was placed intermuscularly in all patients. Follow-ups (FUs) were performed every 6 months. RESULTS: The mean ± standard deviation FU duration was 60.0 ± 11.4 months, with a range of 39 to 78 months. There were no deaths due to arrhythmia, or device-associated infections and complications. Four patients (19.1%) died during FU due to respiratory insufficiency during dialysis, systolic heart failure, septic infection of the urogenital tract, and colorectal cancer, respectively. There were six non-device-related hospitalizations with a duration of 12.7 ± 5.1 days and a hospitalization rate of 4.1 per 100 patient years. CONCLUSIONS: In the long-term FU of this small population of seriously compromised hemodialysis patients at risk of sudden cardiac death, the intermuscularly implanted S-ICD system was safe and effective. No arrhythmic complications, device-associated infections, or complications compromised survival. These data are encouraging and support testing in a larger group of similarly compromised patients.

Earliest Bedside Assessment of Hemodynamic Parameters and Cardiac Biomarkers: Their Role as Predictors of Adverse Outcome in Patients with Septic Shock.

BACKGROUND: Early assessment and aggressive hemodynamic treatment have been shown to increase the survival of patients in septic shock. Current and past sepsis guidelines recommend a resuscitation protocol including central venous pressure (CVP), mean arterial blood pressure (MAP), urine output and central venous oxygen saturation (ScvO2) for resuscitation within the first six hours. Currently, the established severity score systems like APACHE II score, SOFA score or SAPS II score predict the outcome of critically ill patients on the bases of variables obtained only after the first 24 hours. The present study aims to evaluate the risk of short-term mortality for patients with septic shock by the earliest possible assessment of hemodynamic parameters and cardiac biomarkers as well as their role for the prediction of the adverse outcome. METHODS: 52 consecutive patients treated for septic shock in the intensive care unit of one centre (Marien Hospital Herne, Ruhr University Bochum, Germany) were prospectively enrolled in this study. Hemodynamic parameters (MAP, CVP, ScvO2, left ventricular ejection fraction, Hematocrit) and cardiac biomarkers (Troponin I) at the ICU admission were evaluated in regard to their influence on mortality. The primary endpoint was all-cause mortality within 28 days after the admission. RESULTS: A total of 52 patients (31 male, 21 female) with a mean age of 71.4±8.5 years and a mean APACHE II score of 37.0±7.6 were enrolled in the study. 28 patients reached the primary endpoint (mortality 54%). Patients presenting with hypotension (MAP <65 mmHg) at ICU admission had significantly higher rates of 28-day mortality as compared with the group of patients without hypotension (28-day mortality rate 74 % vs. 32 %, p<0.01). Furthermore, the patients in the hypotension present group had significantly higher lactate concentration (p=0.002), higher serum creatinin (p=0.04), higher NTproBNP (p=0.03) and after the first 24 hours higher APACHE II scores (p=0.04). A MAP <65 mmHg was the only hemodynamic parameter significantly predicting the primary endpoint (OR: 4.1, CI: 1.1 - 14.8, p=0.008), whereas the remaining hemodynamic variables CVP, ScvO2, Hematocrit, Troponin I and left ventricular ejection fraction (LVEF) seemed to have no influence on survival. Besides, non-survivors had a significantly higher age (74.1±9.0 vs. 68.4±6.9, p=0.01). If hypotension coincided with an age ≥72 years, the 28-day mortality rate escalated to 88%. CONCLUSIONS: In our study, we identified a risk group with an exceedingly high mortality rate: the patients with an age ≥72 years and presenting with hypotension (MAP <65 mmHg). These data can be easily obtained at the time of the very first patient contact. As a result, an aggressive and a more effective treatment can be initiated within the first minutes of the primary care, possibly reducing organ failure and short-term mortality in this risk group.

Radiofrequency ablation of a left lateral atrioventricular accessory pathway in a 13-year-old boy with a criss-cross heart guided by nonfluoroscopic imaging.

We present the first description of successful radiofrequency (RF) ablation of a bidirectional atrioventricular accessory pathway (AP) guided by nonfluoroscopic mapping with use of three-dimensional magnetic resonance imaging integrated into the Nav-X system (MRI/Nav-X fusion) in a 13-year-old boy with remote surgical palliation for cyanotic criss-cross heart with atrioventricular discordance, double-outlet right ventricle, and a large ventricular septal defect. Due to complex anatomy, a unique finding was that the eliminated left lateral AP electrically connected the left atrium to the antero-superior morphologic right ventricle prior to ablation.

Segment-orientated analysis of two-dimensional strain and strain rate as assessed by velocity vector imaging in patients with acute myocardial infarction.

AIMS: Strain rate imaging techniques have been proposed for the detection of ischemic or viable myocardium in coronary artery disease, which is still a challenge in clinical cardiology. This retrospective comparative study analyzed regional left ventricular function and scaring with two-dimensional strain (2DS) in the first 4 to 10 days after acute anterior myocardial infarction (AMI). METHODS AND RESULTS: The study population consisted of 32 AMI patients with an LAD occlusion and successful reperfusion. The assessment of peak systolic 2DS and peak systolic strain rate (SR) was performed segment-oriented with the angle-independent speckle tracking algorithm Velocity Vector Imaging (VVI). The infarcted, adjacent and non-infarcted segments were revealed by late enhancement MRI (LE-MRI), which was used as reference for the comparison with 2DS. The infarcted segments showed a significant decrease of tissue velocities, 2DS and SR in comparison to the non-affected segments. CONCLUSION: 2DS and SR as assessed by VVI seem to be a suitable approach for echocardiographic quantification of global and regional myocardial function as well as a promising tool for multimodal risk stratification after anterior AMI.

New-onset versus chronic atrial fibrillation in acute myocardial infarction: differences in short- and long-term follow-up.

AIMS: Atrial fibrillation (AF) occurs commonly in patients with acute myocardial infarction (AMI) and has been established as a marker of adverse prognosis. There are only few clinical trials that investigate differences between new-onset and chronic AF in AMI. We hypothesize that chronic AF is associated with an increased rate of adverse short- and long-term outcomes. METHODS AND RESULTS: In a single center study, over a period of 28 months, 375 consecutive patients with AMI were included [337 patients without AF (89.9%) and 38 with AF (10.1%)]. As much as 16 patients had new-onset AF (42.1%) and 22 had chronic AF (57.9%). Patients with severe coronary artery disease develop AF more often in AMI, and the existence of AF was associated with a poor prognosis. Compared to patients with new-onset AF, chronic AF was more frequently associated with advanced age (75 vs. 70 years, p not significant), reduced left ventricular ejection fraction (44.8 vs. 54.0%, p < 0.05) and NSTEMI (63.6 vs. 36.4%, p < 0.05). Only chronic AF resulted in increased in-hospital death (18.2 vs. 0.0%; p < 0.005) at the 2-year follow-up, 14 patients with AF died (63.6%), predominantly due to cardiovascular reasons. CONCLUSION: Our results indicate that patients with chronic AF had a higher incidence of in-hospital death than those with new-onset AF or without. Chronic AF includes a group of older and sicker patients than their counterparts with new-onset AF. Understanding these findings may ultimately lead to better care of patients with this arrhythmia to prevent the development of the underlying atrial substrate in chronic AF patients and to improve their otherwise worse prognosis.

The first three-dimensional visualization of a thrombus in transit trapped between the leads of a permanent dual-chamber pacemaker: a case report.

INTRODUCTION: Two-dimensional echocardiography is a useful tool in diagnosing cardiac masses. However, the three-dimensional offline reconstruction technique of transesophageal echocardiography might be superior to two-dimensional transesophageal echocardiography in providing additional information of structural details. CASE PRESENTATION: We report the case of a 76-year-old Caucasian man with a permanent dual-chamber pacemaker and a worm-like right-heart thrombus in transit. Two-dimensional transthoracic echocardiography and two-dimensional transesophageal echocardiography showed that it was debatable as to whether "the worm" was originating from the leads. Offline three-dimensional transesophageal echocardiography reconstruction technique proved superior in identifying the cardiac mass as a thrombus trapped between the leads of the pacemaker. The thrombus was successfully dissolved by systemic heparin therapy. CONCLUSIONS: The three-dimensional transesophageal echocardiography is useful and effective in patients with implanted pacemakers or defibrillators when other closely competing imaging modalities are contraindicated, such as magnetic resonance imaging. In patients with pacemakers and trapped thrombus in transit for whom surgical therapy might be a high risk, medical therapy seems to offer a safer and convincing alternative. Whether the management of right-heart thrombi has to be modified due to the presence of pacemaker leads is controversial.

Contrast medium induced nephropathy in patients undergoing percutaneous coronary intervention for acute coronary syndrome: differences in STEMI and NSTEMI.

UNLABELLED: The aim of this study was to assess the incidence, clinical predictors, and outcome of patients developing contrast medium induced nephropathy (CIN) after percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS). BACKGROUND: CIN is associated with significant higher morbidity and mortality after coronary intervention. Recently it was shown, that patients undergoing percutaneous coronary intervention for acute myocardial infarction have a significant higher risk of developing CIN. Non-ST-elevating myocardial infarction (NSTEMI) patients (pts) might be at an even higher risk developing CIN than patients with ST-elevating myocardial infarction (STEMI), because of presenting older and more often with diabetes. METHODS: In 392 consecutive ACS patients developing myocardial infarction and therefore undergoing emergent coronary angiography between October 2004 and March 2007, we measured serum creatinine concentration (Cr) at baseline and each day of the following 3 days. Contrast medium induced nephropathy was defined as an increase in Cr > 0.5 mg/dl. ACS was defined according to the guidelines of the German Society of Cardiology. RESULTS: Overall, 392 pts were included: 203 (51.8%) with STEMI and 189 (48.2%) with NSTEMI. Patients with STEMI developed more often a cardiogenic shock (18 vs. 6%; P < 0.001) whereas patients with NSTEMI were older (67 vs. 61 years; P < 0.001) and presenting with a higher co-morbidity. Forty-five (11.5%) pts developed CIN; 22 (10.8%) in the STEMI group and 23(12.2%) in the NSTEMI group (P = 0.75). Patients developing CIN presented a more complicated clinical course and a significantly longer hospital stay (14 vs. 10 days; P < 0.001). The mortality rate was also significantly higher (16 vs. 6%; P < 0.05). CONCLUSION: This prospective study showed no differences in the incidence of developing CIN in patients undergoing PCI for STEMI or NSTEMI, but the predisposing factors, however, differed significantly. Although STEMI patients needed significantly more contrast medium for revascularisation, they did not develop CIN more often. CIN was associated with higher in-hospital complication rate and mortality. Thus, better preventive strategies according to the different predisposing factors leading to CIN are needed to reduce morbidity and mortality, especially in high risk patients.

Masked diastolic dysfunction caused by exercise testing in hypertensive heart failure patients with normal ejection fraction and normal or mildly increased LV mass.

INTRODUCTION: It is not clear whether in patients with the clinical suspicion of heart failure with normal ejection fraction (HFNEF) exercise assessment of diastolic function may help to unmask abnormalities not detected by resting measurements. METHODS AND RESULTS: A combined radionuclide angiographic and haemodynamic exercise study was performed to confirm definite diastolic dysfunction in hypertensive patients with exertional dyspnoea and no other detectable cause of their symptoms. Only patients with normal baseline left ventricular (LV) systolic and diastolic function parameters as evaluated by routine cardiac catheterization and transmitral Doppler echocardiography were accepted (n = 38). All parameters were compared to a control group (n = 10). Twenty-eight patients showed an abnormal elevation in pulmonary capillary wedge pressure with exercise. As a consequence of a reduced exercise stroke volume (58 +/- 13 vs. 70 +/- 12 ml/m2; P = 0.01) peak cardiac output was reduced in HFNEF (9.3 +/- 1.7 vs. 7.6 +/- 2.0 l/min/m2; P = 0.02). These changes were equally demonstrable in patients with and without ventricular hypertrophy. LV end-systolic wall stress (ESWS) was increased at rest and during exercise in HFNEF patients without hypertrophy. However, a positive relationship between ESWS and the corresponding exercise stroke volume (r = 0.57; P = 0.002) was observed in the entire HFNEF group. CONCLUSION: Detection of diastolic dysfunction in suspected HFNEF is not only a question of the diagnostic methods used, but of the conditions under which the patients are investigated.

[Inhibition of the muscarinic potassium current by KB130015, a new antiarrhythmic agent to treat atrial fibrillation]. / Inhibition des muskarinergen Kaliumionenstroms durch das neue Klasse-III-Antiarrhythmikum KB130015 im Vergleich zu Ibutilide.

BACKGROUND AND PURPOSE: Vagus-induced atrial fibrillation is of particular clinical interest. The muscarinic potassium current I(K(ACh)) mediates the induction of vagus-induced atrial fibrillation. Selective inhibition of I(K(ACh)) seems to be an option to treat atrial fibrillation. The application of amiodarone, presently one of the most important antiarrhythmic agents in the parmacological treatment of atrial fibrillation, is limited by its adverse effects. KB130015, a new amiodarone derivative, and ibutilide are new class III antiarrhythmic agents. METHODS: In guinea-pig atrial myocytes the muscarinic potassium current (I(K(ACh))) was activated by acetylcholine and adenosine. The effect of KB130015 on I(K(ACh)) was measured using the whole-cell voltage-clamp method. RESULTS: KB130015 and ibutilide in a concentration of 50 microM effectively inhibited the muscarinic potassium current. The effect was concentrationdependent and reversible. The half-maximum effective concentration was 0.8 microM (KB130015) and 2.8 microM (ibutilide). The inhibition of I(K(ACh)) was independent of the mode of its activation. The adenosine-induced ion current was as well inhibited by both drugs as the acetylcholine-induced ion current. Via GTP-gamma-S irreversibly activated I(K(ACh)) was also inhibited by KB130015 and ibutilide, whereas intracellular application showed no effect on I(K(ACh)). CONCLUSION: KB130015 and ibutilide are potent inhibitors of IK(ACh). Their effect is most likely mediated by direct interaction with the extracellular part of the ion channel. Acute effects of KB130015 on ventricular myocardium are not known so far. Ibutilide on the other hand is known to inhibit I(kr). KB130015 is a promising antiarrhythmic agent for the pharmacotherapy of vagus-induced atrial fibrillation.

[Vascular complications of percutaneous transradial coronary angiography and coronary intervention]. / Vaskuläre Komplikationen der perkutanen transradialen Koronarangiographie und Koronarintervention.

BACKGROUND AND PURPOSE: Vascular complications following transradial coronary angiography and coronary intervention could severely compromise perfusion of the hand. Drastic complications after cannulation of the radial artery (ischemia of the hand with occlusion of the digital arteries) are published only in brief reports. This study investigates whether percutaneous transradial artery coronary angiography/intervention results in vascular complications. PATIENTS AND METHODS: 93 patients were consecutively studied over a 4-month period. The following data were recorded before and after coronary angiography and/or intervention: diameter of the radial artery, blood volume, flow velocity, and occlusion pressure. Graduation of the stenosis after intervention was done according to the principle of the peak velocity ratio. RESULTS: A transradial coronary angiography/intervention was performed in 93 patients (75 men, mean age 62.5 years) in case of an unremarkable Allen test. Procedural success rate was 97.2%. The intervention could not be completed successfully in three patients (2.8%). Mean vessel diameter increased from 2.46 +/- 1.7 mm (standard deviation [SD]) before intervention to 2.78 +/- 0.69 mm (SD) after intervention; this increase was statistically significant (p = 0.002). Changes in blood flow, flow velocity and occlusion pressure did not reach significance. Vascular complications were seen in nine of 93 patients (10%) after the procedure. No patient mentioned discomfort. No perfusion deficit of the digital arteries was seen. CONCLUSION: The transradial coronary angiography and intervention is a safe method with a high procedural success rate.

[Perspectives and limitations in the treatment of vagus-induced atrial fibrillation. Insights from cellular pharmacology]. / Effektivität und Proarrhythmie bei der pharmakologischen Behandlung des vagal induzierten Vorhofflimmerns. Erkenntnisse aus der zellulären Pharmakodynamik.

BACKGROUND AND PURPOSE: Pharmacological treatment of atrial fibrillation (AF) is limited by induction of malignant ventricular arrhythmias. Developing new drugs, a promising strategy is a more specific treatment of the atria. Muscarinic potassium current (IK[ACh]) is predominantly expressed in supraventricular tissue and mediates the induction of vagus-induced AF. The authors investigated the profile of representative class III drugs in respect to their effect on IK(ACh). METHODS: In rat atrial myocytes, IK(ACh) was activated by acetylcholine (ACh) measured with the whole-cell voltage clamp method. Drugs used: selective IKs blocker chromanole 293B (Cro); IKr blockers sotalol (Sot), dofetilide (Dof), ibutilide (Ibu), and terikalant (Ter). Data are expressed as mean values +/- standard deviation (SD). RESULTS: ACh-induced IK(ACh) density was 73 +/- 9 pA/pF (n= 9). IK(ACh) was almost completely desensitized in the presence of 50 micro M Ter, Ibu, or Dof. IC(50) of IK(ACh) inhibition by the three drugs was 0.9, 2.8, and 4.2 micro M (Dof, Ibu, and Ter, respectively). Receptor-independent GTP-gamma-S-induced IK(ACh) was sensitive to Ter, Ibu, and Dof as well. Sot is known to be a weak inhibitor of IKr. Inhibition of IK(ACh) by Sot was much less potent (IC(50) = 35.5 micro M) than inhibition by the high-affinity IKr blockers Ter, Ibu, and Dof. Superfusion of the cells with the IKs blocker Cro showed no desensitization of IK(ACh). Applied via the patch pipette (< 40 min) none of the class III drugs were effective. CONCLUSION: The results indicate inhibition of IK(ACh) and IKr but not IKs to be of similar mechanism (direct ion channel inhibition from the external side of the membrane). Potent desensitization of muscarinic potassium current could be of clinical relevance especially in patients with vagus-induced AF.