Showing papers by "St. Jude Medical Center published in 2012"

Worldwide experience with the robotic navigation system in catheter ablation of atrial fibrillation: methodology, efficacy and safety.

Abstract: Worldwide Survey on Robotic AF Ablation. Introduction: The Hansen Robotic system has been utilized in ablation procedures for atrial fibrillation (AF). However, because of the lack of tactile feedback and the rigidity of the robotic sheath, this approach could result in higher risk of complications. This worldwide survey reports a multicenter experience on the methodology, efficacy, and safety of the Hansen system in AF ablations. Methods and Results: A questionnaire addressing questions on patient's demographics, procedural parameters, ablation success rate and safety information was sent to all centers where more than 50 robotic AF ablation cases have been performed. From June 2007 to December 2009, 1,728 procedures were performed at 12 centers utilizing the Hansen robotic navigation technology. The overall complication rate was 4.7% and the success rate was 67.1% after 18 ± 4 months of follow-up. In 5 low volume centers there appeared to be a learning curve of about 50 cases (complication rate 11.2% for the first 50 cases vs 3.7% for the 51–100 cases; P = 0.044) and a trend showing a decrease of complication rate with increasing case volume. However, in the remaining 7 centers no learning curve was present and the complication rate was stable over time (3.7% for the first 50 cases vs 3.6% for the 51st case thereafter; P = 0.942). Conclusion: The Hansen robotic system can be used for AF ablation safely. In low volume centers, there appeared to be a learning curve of the first 50 cases after which the complication rate decreased. With a higher case volume, the success rate increased. (J Cardiovasc Electrophysiol, Vol. 23, pp. 820-826, August 2012)

Consensus Statement on Effective Communication of Urgent Diagnoses and Significant, Unexpected Diagnoses in Surgical Pathology and Cytopathology From the College of American Pathologists and Association of Directors of Anatomic and Surgical Pathology

Abstract: Context.—Recognizing the difficulty in applying the concept of critical values to anatomic pathology diagnoses, the College of American Pathologists and the Association of Directors of Anatomic and Surgical Pathology have chosen to reevaluate the concept of critical diagnoses. Objective.—To promote effective communication of urgent and significant, unexpected diagnoses in surgical pathology and cytology. Design.—A comprehensive literature search was conducted and reviewed by an expert panel. Results.—A policy of effective communication of important results in surgical pathology and cytology is desirable to enhance patient safety and to address multiple regulatory requirements. Conclusions.—Each institution should create its own policy regarding urgent diagnoses and significant, unexpected diagnoses in anatomic pathology. This policy should be separate from critical results or panic-value policies in clinical pathology, with the expectation of a different time frame for communication. Urgent diagnosis is d...

First In Vivo Use of a Capacitive Micromachined Ultrasound Transducer Array–Based Imaging and Ablation Catheter

Abstract: Electrophysiologic interventions have had increasing popularity as treatment options for arrhythmias, particularly atrial fibrillation.1 Atrial fibrillation is the most common arrhythmia, with an incidence of 2 to 3 per 1000 people aged 55 to 64 years annually,2 and is associated with considerable morbidity and mortality.3,4 There are at least 3 techniques available to interventionalists that can accurately locate intracardiac regions of interest, with fluoroscopy being the most established technique. However, the exposure to ionizing radiation, as well as the inability of fluoroscopy to clearly delineate subsurface intracardiac regions and confirm catheter contact with the endocardium, has made echocardiography and electroanatomic mapping (EAM) the most attractive as adjunct modalities.5–9 Intracardiac echocardiography (ICE), in particular, has found multiple uses in the electrophysiology laboratory, providing real-time display of intracardiac structures.6–8 The use of ultrasound image guidance for interventional radiofrequency ablation (RFA) procedures in the heart has begun to play a more important role in the minimization of fluoroscopic radiation exposure to the patient while imaging important intracardiac features, eg, the membranous fossa of the interatrial septum for puncture access to the left atrium, the pulmonary veins, and Doppler blood velocities associated with pulmonary vein stenosis.10 Important considerations in the design of ICE catheters are the (1) imaging and handling performance features, (2), compatibility with current interventional practice, and (3) cost in both procedural time and purchasing expense. Overall, a catheter that can be itself guided into place with EAM, perform high-quality image guidance of RFA therapy, and improve procedural throughput at a lower cost is a worthwhile goal. As a general guide, Table 1 compares the common RFA catheter with an “ideal” catheter and with the initial features of a proposed progenitor, a microlinear capacitive micromachined ultrasound transducer (ML-CMUT) catheter. Table 1 Performance Parameter Objectives for Catheters Used in Radiofrequency Ablation Procedures The miniaturization of ICE catheters has revolutionized interventional procedures by integrating ultrasound transducers onto flexible, low-profile catheters, which allow imaging in the restricted spaces of vascular and cardiac structures.11–13 Two distinctly different ICE catheter prototypes, descriptively referred as ML catheters because of their small ultrasonic array designs, have been developed within a program to build a series of miniaturized high-frequency forward-looking transducer arrays.14 Piezoceramic arrays, namely those made with lead zirconate titanate (PZT), are considered standard design types for most ultrasound applications. Currently in their third generation of development, our early ML devices are called ML-PZT array catheters. The second array transducer type is the CMUT, now in its second generation of development15; these CMUT arrays are used in the assembly of the ML-CMUT array catheter (Figure 1). By comparison to PZT, the CMUT as an acoustic transducer is relatively new as an ultrasound transceiver. This silicon-based array, however, has several design aspects that may yield a considerable advantage over the PZT array type, especially at small sizes. The small-element CMUT array in combination with a local buffer-preamplifier offers excellent transmit and receive sensitivity with a wide bandwidth, allows special element shaping, does not require acoustic matching layers, and may be considerably less expensive in large-scale manufacturing. Figure 1 Prefinished distal tip (a) of the 9F microlinear capacitive micromachined ultrasound transducer (CMUT) intracardiac imaging catheter with a metal radiofrequency ablation tip electrode, and the 24-element CMUT array (b) with silicon die dimensions of 1.9 ... The principal objective of this work is to describe the first in vivo use of a forward-looking ML-CMUT array catheter in a true 9F profile, the catheter compatibility with EAM guidance, and the use of a specially integrated RFA tip capable of both monitoring and delivery of intracardiac ablation. This work represents the first in vivo ablation and direct simultaneous collection of tissue echo data for the thermal strain temperature at the exact ablation site. In addition, we describe the initial use of the ML-CMUT catheter in exploratory cardiac imaging from the perspective of the epicardial surface from within the pericardium.

The patient-reported Clinicians’ Cultural Sensitivity Survey: a field test among older Latino primary care patients

Abstract: Author(s): Napoles, Anna M; Santoyo-Olsson, Jasmine; Farren, Georgianna; Olmstead, Jill; Cabral, Ruben; Ross, Barry; Gregorich, Steven E; Stewart, Anita L | Abstract: BackgroundPatient-reported measures of clinicians' cultural sensitivity are important to assess comprehensively quality of care among ethnically diverse patients and may help address persistent health inequities.ObjectiveCreate a patient-reported, multidimensional survey of clinicians' cultural sensitivity to cultural factors affecting quality of care.DesignUsing a comprehensive conceptual framework, items were written and field-tested in a cross-sectional telephone survey. Multitrait scaling and factor analyses were used to develop measures.Setting and participantsLatino patients age ≥50 from primary care practices in California.Main variables studiedThirty-five items hypothesized to assess clinicians' sensitivity.Main outcomes measuresValidity and reliability of cultural sensitivity measures.ResultsTwenty-nine of 35 items measuring 14 constructs were retained. Eleven measures assessed sensitivity issues relevant to all participants: complementary and alternative medicine, mind-body connections, causal attributions, preventive care, family involvement, modesty, prescription medications, spirituality, physician discrimination due to education, physician discrimination due to race/ethnicity and staff discrimination due to race/ethnicity. Three measures were group specific: two to limited English proficient patients (sensitivity to language needs and discrimination due to language) and one to immigrants (sensitivity to immigrant status). Twelve multi-item scales demonstrated adequate reliability (alpha ≥0.68 except for Spanish discrimination due to education) and evidence of construct validity (item-scale correlations for all scales g0.40 except for sensitivity to immigrant status). Two single-item measures demonstrated sufficient construct validity to retain for further development.Discussion and conclusionsThe Clinicians' Cultural Sensitivity Survey can be used to assess the quality of care of older Latino patients.

Acute Clinical Evaluation of a Left Ventricular Automatic Threshold Determination Algorithm Based on Evoked Response Sensing

Abstract: Introduction:Automatic pacing threshold (AT) testing may simplify device follow-up and improve device longevity. This study's objective was to evaluate the performance of a left ventricular (LV) evoked response sensing-based AT algorithm, for cardiac resynchronization therapy (CRT) devices. Methods:Patients scheduled for CRT-D/P implant were enrolled. A manual step-down threshold test and a Left Ventricular Automatic Threshold (LVAT) test in each of four pacing vectors—LVTipCan, LVTipright ventricle (RV),= LVRingCan, and LVRingRV—were conducted. Patients were randomized to either 0.4-ms or 1.0-ms pacing pulse width and in the manual and LVAT test order. A blinded core lab electrophysiologist (EP) determined the threshold using the surface electrocardiogram (gold standard). Results:Data from 70 patients were analyzed. Bipolar LV leads from three major manufacturers were used. A total of 273 AT tests were performed; 12 AT tests did not result in a threshold due to improper testing conditions. Of 261 eligible tests, 234 AT tests (89.6%) returned a threshold measurement. Of the 234 tests, in 233 tests (99.5%) the algorithm-determined threshold matched the EP-determined threshold for that test. A total of 16,689 capture and 526 noncapture beats were collected and the accuracy for detecting capture and noncapture were 98.5% and 99.7% with a two-sided 95% confidence level of (98.4%, 98.7%) and (99.4%, 100%), respectively. No AT threshold measurement was lower than the EP-determined threshold. Conclusion:In this study, the results suggest that the LVAT algorithm is accurate at determining pacing thresholds in multiple pacing configurations and a wide range of LV leads in CRT-D/P patients. (PACE 2011;1–5)

Feasibility and advantages of using flattening filter-free mode for radiosurgery of multiple brain lesions.

Abstract: Purpose The 6-MV flattening filter-free mode (6F) of the Varian TrueBeam (Varian Medical Systems, Palo Alto, CA) enables faster dose delivery and shortens treatment time, which are especially beneficial for stereotactic radiosurgery. This study is to evaluate the feasibility and advantages of using 6F in stereotactic radiosurgery treatment of multiple brain lesions in comparison with regular 6-MV mode (6X). Materials and Methods Ten patients having 2-12 brain metastases treated by intensity modulated stereotactic radiosurgery were selected for this study. For each patient, 2 RapidArc (RA; Varian Medical Systems) plans were generated: one using the 6F mode with a dose rate of 1400 monitor units (MU)/minute and another using the regular 6X mode of 600 MU/minute for a Varian TrueBeam linac. For each patient, both plans employed the same beam arrangement and optimization process. Results The dosimetric parameters of homogeneity, conformity, and gradient indices were calculated and found to be comparable in the 6F and 6X plans for each patient. The mean dose to the normal brain and maximal doses to brainstem, chiasm, eyes, and optical nerves were also comparable in both RA plans using either 6F or 6X. The total number of MUs in the RA plans using 6F was 10%-20% more than that in the RA plan using 6X, but the beam-on-time was much less if 6F was used for planning and dose delivery (50% less). Conclusions The fast delivery of the 6F beam is not only beneficial in stereotactic radiosurgery of a single brain lesion, but also for treating multiple brain lesions (2-12 lesions in this study group). Due to the beam falloff away from the central axis for large field sizes, more MUs are needed for 6F beams as compared with 6X. However, for the 6F mode with 1400 MU/minute, the delivery times are still much shorter compared with the 6X mode, thus greatly shortening the treatment time.

Results of a School-Based Obesity Prevention Program Targeting Early Childhood Students

Abstract: The purpose of this study was to determine whether early childhood students who participated in the Healthy for Life/PE4ME program experienced significant changes in their age-adjusted body mass index (BMI) percentiles, obesity-related behaviors, and identification of healthy foods and physical activities. The school-based program included nutrition education and physical activity components implemented by the teacher and program dietitian. Participants were 356 children and their parents, in17 Southern California schools with a high percentage of ethnically diverse, low income students. Parents completed a survey assessing their children’s demographics; family medical history; and obesity-related lifestyle behaviors; at pre-test and post-test. Students completed a picture scale activity to assess their ability to identify healthy versus. unhealthy foods and active vs. less active physical activities. BMI percentiles significantly decreased among children who were overweight or obese at pre-test; they also significantly decreased their junk food consumption (e.g., soda, Cheetos©). Obese children at pre-test significantly decreased their consumption of whole milk and increased their consumption of low-fat milk. Normal weight children significantly increased their consumption of milk and their physical activity. These findings provide preliminary evidence that the Healthy for Life/PE4ME program may be effective in reducing the childhood obesity trend in Orange County preschool children.

Volume Status and Fluid Responsiveness

Abstract: To the Editor, Dr. Lazaridus has presented a great review of advanced hemodynamic monitoring (AHM) [1]. Significant caution though must be used in accepting the accuracy of any noninvasive cardiac output methodology. The FDA 510 K approval process is not very rigorous and the comparison of noninvasive to invasive cardiac output (CO) is not done over a very large range of loading and unloading conditions. Hadian et al. [2] showed that FloTrac as well as other noninvasive CO devices showed widely varying results as compared to thermodilution (TD) CO and more importantly could trend in different directions under different loading conditions. The differences were in a range where therapy choices could be affected; possibly adversely. This type of testing is more clinically relevant and rigorous than the methodology used by Mutoh et al. [3] which assessed effects of volume loading but not that of vasoactive or inotropic drips. We have evaluated another noninvasive CO device in our unit, Cheetah, which measure CO by assessing changes in thoracic impedance and often found results diverging significantly from TD CO (unpublished data). In addition one of the statements ‘‘The ultimate goal of volume expansion is augmentation of stroke volume ...’’ may not be completely accurate. There is evidence that excess volume expansion may worse renal failure and increase mortality in the setting of sepsis [4, 5]. The fact that the patient is fluid responsive as evidenced by passive leg raise (PLR) test does confirm that the patient is not on the flat portion of the Frank-Sterling curve. However since cardiac output is not necessarily the goal endpoint of fluid resuscitation and excess fluid can cause harm, further data is needed before accepting results of PLR as a clinical volume resuscitation endpoint.

Neuro Excellence in the ICU Another Model for a Neuro-ICU

Abstract: There is significant literature showing improved outcomes in patients who are cared for in a specialized neurocritical care unit. The authors propose a model where the key aspects of specialized neurocrticial care can be provided within the framework of an existing ICU in an efficient and effective manner as an alternative to a separate neurocritical care unit. The key aspects of programmatic success are described.