Biomedical subjects

Jörg Neuzner

Publications and source records attributed to Jörg Neuzner.

5 recordsLinked to original sources

PubMed2006

Improved clinical outcome after intracoronary administration of bone-marrow-derived progenitor cells in acute myocardial infarction: final 1-year results of the REPAIR-AMI trial.

AIMS: To investigate the clinical outcome after intracoronary administration of autologous progenitor cells in patients with acute myocardial infarction (AMI). METHODS AND RESULTS: Using a double-blind, placebo-controlled multicentre trial design, we randomized 204 patients with successfully reperfused AMI to receive intracoronary infusion of bone-marrow-derived progenitor cells (BMCs) or placebo medium into the infarct artery 3-7 days after successful infarct reperfusion therapy. At 12 months, the pre-specified cumulative endpoint of death, myocardial infarction, or necessity for revascularization was significantly reduced in the BMC group compared with placebo (P=0.009). Likewise, the combined endpoint death, recurrence of myocardial infarction, and rehospitalization for heart failure was significantly (P=0.006) reduced in patients receiving intracoronary BMC administration. Intracoronary administration of BMC remained a significant predictor of a favourable clinical outcome by Cox regression analysis, adjusting for classical predictors of poor outcome after AMI. CONCLUSION: Intracoronary administration of BMCs is associated with a significant reduction of the occurrence of major adverse cardiovascular events after AMI. Large-scale studies are warranted to confirm the effects of BMC administration on mortality and morbidity in patients with AMIs.

Adolescent↗

PubMed2006

Patient Alert to detect ICD lead failure: efficacy, limitations, and implications for future algorithms.

AIMS: An algorithm that alerts implantable cardioverter-defibrillator (ICD) patients, in case of abnormal lead impedance (Patient Alerttrade mark, Medtronic), may help to recognize lead dysfunction. We aimed to determine the utility of Patient Alert for ICD lead-failure detection in a prospective study. METHODS AND RESULTS: Three hundred and sixty ICD patients were followed for 22+/-14 months. Patient Alert was active for pacing impedance <200 and >2000-3000 Omega, and high-voltage conductor impedance <10-20 and >200 Omega. Ten alert events and a total of 29 severe system complications occurred. Patient Alert detected three of 10 ICD lead failures, with a positive predictive value (PPV) of 77.8% for any severe system complication. Retrospective analysis identified 23 patients with a sensing integrity counter (SIC) >300 and revealed an additional four prior undetected lead defects. SIC detected ICD lead failure with 92.9% sensitivity and a PPV of 59.1%. Eight of nine patients with a false-positive SIC had an integrated bipolar lead. Patient Alert combined with SIC detected all ICD lead failures and 71.4% of all severe lead complications. CONCLUSIONS: Patient Alert, based on daily lead-impedance measurement, detected one-third of all ICD lead failures. Combined use with continuous lead integrity monitoring (SIC) increased sensitivity to 100%. Integrated bipolar leads may yield a false-positive SIC. Incorporating SIC and automated pace/sense threshold measurement may improve Patient Alert sensitivity for severe lead complications.

Aged↗

PubMed2005

[Is DFT testing still mandatory?].

The automatic detection and termination of ventricular fibrillation is still the key function of implantable cardioverter defibrillator (ICD) therapy. The progress in generator and lead technology has overcome limitations in defibrillation efficacy in early transvenous defibrillator devices. Current, active pectoral biphasic devices provide a high defibrillation efficacy. More than 90% of all patients will meet accepted implantation criteria without any intraoperative system modifications. Is this enough to abandon the intraoperative assessment of defibrillation efficacy? Arguments for abandoning intraoperative device testing include: reduction of perioperative complications, time and cost saving, no worse prognosis for defibrillator patients with borderline defibrillation efficacy, DFT testing might be a barrier to an easy access to ICD implantation. Abandoning intraoperative assessment of defibrillation efficacy may result in inadequate defibrillation safety in up to 9% of all patients. The noninferior outcome of patients with nonadequate defibrillation efficacy is not already proven. Intraoperative device testing could be limited to a small number of VF inductions, the safety of these protocols is well established. A significant time and cost reduction is not really existing. The abandoning of defibrillation testing will not lead to an increase in ICD implant capacity. The intraoperative assessment of defibrillation efficacy should be an important part of ICD implantation.

Clinical Trials as Topic↗

PubMed2002

Adjustment of maximum automatic sensitivity (automatic gain control) reduces inappropriate therapies in patients with implantable cardioverter defibrillators.

Patients with ICDs might experience oversensing associated with inappropriate shock therapy when paced at low bradycardia rates or if they have a low intrinsic rhythm. The amplifier gain of automatic gain control is maximal at long RR intervals and might lead to oversensing of myopotentials. The hypothesis was that an individual adjustment of the sensitivity floor could reduce inappropriate ICD therapies. Fourteen patients implanted with the VENTAK MINI I/II and III in whom oversensing and/or inappropriate shocks had been documented were included in this evaluation based on stored episodes. Sensitivity was modified in all ICDs by means of noninvasive software downloading that allowed reprogramming of the maximum sensitivity from 0.14 mV in two steps to 0.27 mV ("Normal," "Less," "Least"). Provocation testing (deep inspiration, sit-ups, and abdominal pressing) was conducted at "Nominal" settings (0.14 mV) while the intracardiac electrogram with annotated event marker was running continuously and was repeated at 0.22 mV (Less) and 0.27 mV (Least). All patients evaluated had documented spontaneous episodes due to oversensing before the sensitivity floor was reprogrammed. During provocation testing at Nominal settings, oversensing could be documented in 9 of (64.3%) 14 patients. Provocation testing was repeated after the sensitivity selection was reprogrammed and oversensing could not be provoked in any of the 14 implanted devices. Sensitivity was reprogrammed in all 14 patients to a higher value (5 patients Less, 9 patients Least). After sensitivity adjustment, VF was induced in all patients to verify appropriate arrhythmia detection and termination. Sensitivity reprogramming in patients with documented oversensing eliminates the incidence of inappropriate shock therapy without compromising the ability to detect VF appropriately.

Algorithms↗

PubMed2002

Transcatheter closure of atrial septal defect and patent foramen ovale in adult patients using the Amplatzer occlusion device: no evidence for thrombus deposition with antiplatelet agents.

Transcatheter closure of atrial septal defect (ASD) and patent foramen ovale (PFO) using the Amplatzer septal occluder (AGA Medical, Minneapolis, Minn) is an alternative to surgical closure. There are only limited data on the thrombogenic potential of the device. Thirty-seven patients (14 men, 23 women) underwent device closure of their ASD (n = 21) or PFO (n = 16) at a mean age of 47 +/- 14 years (range, 18-72). The device was successfully deployed in all patients. Thirty-three of 37 patients received antiplatelet therapy with clopidogrel bisulfate and aspirin for a total of 6 months. Four patients in atrial fibrillation were also anticoagulated (international normalized ratio 2.0 to 3.0). No thrombus was detected in any patient on either side of the device by transthoracic and transesophageal echocardiography and there were no cases of symptomatic thromboembolism. Right-to-left interatrial shunting was diagnosed by contrast transesophageal echocardiography with the Valsalva's maneuver. At 1-month follow-up, minimal right-to-left shunting was detected in 6 patients (2 PFO, 4 ASD). Two patients (PFO) had minimal shunting at 1 month but not at 6 months. In 3 patients (ASD), inducible right-to-left shunting persisted at 6 months. In conclusion, our results obtained from a modest number of patients indicate that antiplatelet therapy is safe and effective in preventing thrombus formation on the septal occluder surface.

Adolescent↗