Relation Between Body Surface Mapping and Endocardial Spread of Ventricular Activation in Postinfarction Heart

INTRODUCTION: Body surface mapping (BSM) can be used to identify the site of earliest endocardial activation of ventricular tachycardias (VTs). The multielectrode QRS morphology during VT is determined by both the site of earliest activation and the subsequent spread of electrical activation through the ventricles. This study investigated the relationship between the site of earliest endocardial activation, endocardial spread of activation, and the morphology of the multielectrode surface map in patients with remote myocardial infarction. METHODS AND RESULTS: In 14 patients with VT late (8.2+/-5.2 years) after myocardial infarction, BSM and simultaneous left ventricular 64-site basket endocardial mapping was performed during a total of 17 monomorphic VTs. In addition, multisite pacing by sequential use of the 64 basket electrodes was performed in 9 patients. BSM and basket mapping revealed the same endocardial breakthrough sites in 8 (47%) of 17 VTs and 189 (59%) of 322 pacing sites; adjacent sites were found in 2 (12%) of 17 VTs and 36 (11%) of 322 pacing sites. Large zones of conduction block explained the mismatch in localization in 2 (12%) of 17 VTs and 52 (16%) of 322 pacing sites. Regional differences in endocardial electrogram amplitudes were found as a cause for dissimilarity in 3 (18%) of 17 VTs and 73 (23%) of 322 pacing sites. Multiple endocardial breakthrough sites were found in 1 (6%) of 17 VTs and 8 (2%) of 322 pacing sites Finally, an epicardial exit site was suggested in 3 (18%) of 17 VTs as an explanation for mismatch, as no early endocardial activity could be recorded. CONCLUSION: Zones of conduction block, regional differences in signal amplitude, and multiple endocardial breakthrough sites are frequent causes for mismatch between BSM and basket catheter activation mapping.     

The Impact of Modern Noninvasive Cardiac Imaging on Coronary Intervention Rates

Objectives

It remains still unclear whether the use of modern noninvasive diagnostic modalities for evaluation of coronary artery disease (computed tomography coronary angiography (CTCA), nuclear myocardial perfusion imaging (MPI)) were able to change the “diagnostic yield” of invasive coronary angiography (ICA).

Methods

The total number of ICA in the years 2000–2009 was related to the number of percutaneous interventions (PCIs) and we assessed whether there was a significant trend over time using time series analyses. We compared these data with the number of patients undergoing CTCA and nuclear MPI in the same time period.

Results

During the 10‐year observational period, 23,397 ICA were performed. The proportion of purely diagnostic ICA (without PCI) remained stable over the whole study period (tau = ?0.111, P = 0.721). A CTCA program was initiated in 2005 and 1,407 examinations were performed until 2009. Similarly, the number of nuclear MPI increased from 2,284 in the years 2000–2004 to 5,260 in the years 2005–2009 (P = 0.009).

Conclusion

Despite increasing availability, noninvasive testing modalities did not significantly alter the rate of purely diagnostic ICA, and still are underused as gatekeeper to ICA. Further effort is needed to optimize the use of noninvasive imaging modalities in the work‐up process for coronary artery disease. (J Interven Cardiol 2014;27:50–57)

     

Improvement of Quality of Life by Means of Antitachy Pacing: From PainFREE to the ADVANCE-D Trial

Background: Implantable cardioverter-defibrillators (ICD) can terminate ventricular tachyarrhythmias with shocks (painful) or antitachycardia pacing (painless). According to the results of the Pacing Fast VT Reduces Shock ThErapies Trials, antitachycardia pacing (ATP) can avoid painful shocks and also increase device longevity. The purpose of the ADVANCE-D (Atp DeliVery for PAiNless ICD ThErapy) study is to determine the most appropriate ventricular tachycardia (VT) therapy, so as to optimize painless therapy for life-threatening arrhythmias.
Methods and Results: The ADVANCE-D is a prospective, multicenter, parallel, two-arm randomized study designed to evaluate the efficacy of two different sequences of ATP therapies (burst 15 pulses, 88%, vs burst 8 pulses, 88%), during an episode of spontaneous arrhythmia classified as fast VT (FVT) in patients with a Class I or IIA indication for ICD implantation (single and dual chamber devices). The primary endpoint is to compare the efficacy of two ATP therapies for FVT episodes. The study will enroll a minimum of 900 patients within 2 years, followed-up for 12 months. The investigation is expected to be completed in 2007.
Conclusions: The ADVANCE-D trial is the first large randomized clinical investigation aimed to evaluate optimal programming and efficacy of ATP.     

Streptococcus pyogenes and β‐lactam antibiotics

Letters to the Editor are welcomed for publication (subject to editing). Letters must be signed by all authors, typewritten double spaced, and must not exceed two pages of text including references. Two copies of all letters should be submitted along with one copy on disk. Letters should not duplicate material submitted or published in other journals. Prepublication proofs will not be provided.     

Natural and Restorative Oral Esthetics Part II: Esthetic Treatment Modalities

A previous article, Journal of Esthetic Dentistry, Volume 5, Number 4, 161-173 (Part I) described the basic strategies for successful esthetic rehabilitation, including the knowledge about natural oral esthetics and the interactive relationship between patient-clinician-technician. This article presents the actual choice of current esthetic treatment modalities. Constantly evolving due to continuous improvement of materials and techniques, the treatment alternatives include a "crescendo" of methods that stretch from the very conservative (chemical treatments, direct composite resins) to the more invasive and sophisticated (laminate veneers, full ceramic FPDs). Using selected clinical cases, a rationale is described for the choice of the appropriate technique related to a specific clinical situation.