Intraoperative Defibrillation Testing Should Not Be Generally Abandoned for All ICD Procedures-A Multicenter Study on 4,572 Consecutive Patients.

Background The ongoing technical advances in development of new implantable cardioverter defibrillator (ICD) systems led some investigators to question the routine use of intraoperative defibrillation testing (DT). Therefore, we evaluated retrospectively in a multicenter study effectiveness, safety, and usefulness of intraoperative DT on unbiased large patient population. Methods Data from 4,572 consecutive patients undergoing any ICD intervention were retrospectively analyzed. Besides efficacy of DT, risk factors for DT failure were identified in a multiple logistic regression analysis. Results Overall 5,483 shock data from 4,532 patients were available. Not tested for medical reasons were 13.5%. DT-associated complications were not noted. Primary DT effectiveness was 95.8%, whereas 4.2% were ineffective. Optimization (51.6% increase of DT energy, 10.1% subcutaneous lead array (SQ array), 2% generator exchange, 4.8% lead reposition, 9.3% lead exchange, and 22.2% change of shock parameters) led to successful DT in 152 patients (96.2%). Subanalyses and logistic regression identified implantation of generator in any other position than left subpectoral, age, body mass index and left ventricular ejection fraction as independent predictors for primary DT failure. Conclusion The number of patients, including those undergoing generator exchange, system upgrade, or system revision, with inappropriate intraoperative testshock is relatively high. The results of recent prospective clinical trials can be extrapolated only on first ICD implantations with high-energy generators. For patients undergoing subcutaneous ICD implantation, right-sided implantation, patients with channelopathies and hypertrophic cardiomyopathy, as well as for procedures on already implanted ICD systems, the intraoperative DT might still be recommended.

Fluid status telemedicine alerts for heart failure: a randomized controlled trial.

AIMS: Hospital admissions are frequently preceded by increased pulmonary congestion in heart failure (HF) patients. This study evaluated whether early automated fluid status alert notification via telemedicine improves outcome in HF patients. METHODS AND RESULTS: Patients recently implanted with an implantable cardioverter defibrillator (ICD) with or without cardiac resynchronization therapy were eligible if one of three conditions was met: prior HF hospitalization, recent diuretic treatment, or recent brain natriuretic peptide increase. Eligible patients were randomized (1:1) to have fluid status alerts automatically transmitted as inaudible text message alerts to the responsible physician or to receive standard care (no alerts). In the intervention arm, following a telemedicine alert, a protocol-specified algorithm with remote review of device data and telephone contact was prescribed to assess symptoms and initiate treatment. The primary endpoint was a composite of all-cause death and cardiovascular hospitalization. We followed 1002 patients for an average of 1.9 years. The primary endpoint occurred in 227 patients (45.0%) in the intervention arm and 239 patients (48.1%) in the control arm [hazard ratio, HR, 0.87; 95% confidence interval (CI), 0.72-1.04; P = 0.13]. There were 59 (11.7%) deaths in the intervention arm and 63 (12.7%) in the control arm (HR, 0.89; 95% CI, 0.62-1.28; P = 0.52). Twenty-four per cent of alerts were not transmitted and 30% were followed by a medical intervention. CONCLUSION: Among ICD patients with advanced HF, fluid status telemedicine alerts did not significantly improve outcomes. Adherence to treatment protocols by physicians and patients might be challenge for further developments in the telemedicine field.

Stimulated Acoustic Emission Nonbackscatter Contrast Effect of Microbubbles Seen with Harmonic Power Doppler Imaging.

Transient imaging has been introduced to enhance the signal intensities when using echo contrast agents. However, this phenomenon is not clearly understood. To evaluate the mechanisms of this phenomenon, isolated pig hearts were investigated with different echo imaging techniques in the beating, working heart as well as in an asystolic state without any motion of the heart. The hearts of five German farm pigs (21 +/- 2.5 kg) were surgically explanted and inserted in an artificial circulation providing physiological flow and pressures. Levovist in the dosage of 0.05-0.3 g was injected into the left atrium and contrast effects evaluated in the left ventricular (LV) cavity and in the myocardium with an ultrasound imager (ATL, HDI 3000) equipped with a prototype software for harmonic imaging. Harmonic B-scans and power Doppler registrations were performed with continuous and intermittent recordings (ECG triggered at end-systole) in the beating heart and using an external trigger in the asystolic heart in which perfusion was interrupted for 20 seconds. In the beating pig heart, transient harmonic power Doppler imaging provided intensive opacification of the LV cavity and visible myocardial uptake when ECG triggering was performed. In the asystolic pig heart, with uninterrupted perfusion, both triggered and nontriggered registrations showed contrast signals in the LV cavity and in the myocardium. These findings cannot be explained with the known physics of ultrasound contrast media. Stimulated acoustic emission occurring during disintegration of the microbubbles in the acoustic field would explain this phenomenon, which has not yet been described for Levovist.