St. Jude Medical (st. + jude_medical)

Distribution by Scientific Domains


Selected Abstracts


Redo-OPCAB via Left Thoracotomy Using Symmetry Aortic Connector System:

JOURNAL OF CARDIAC SURGERY, Issue 1 2004
A Report of Two Cases
This approach has also been successfully used in off-pump coronary artery bypass (OPCAB). Traditionally, the grafts have been anastomosed proximally to the descending thoracic aorta or the left subclavian artery. Recently, proximal connectors have been introduced by various manufacturers for use on ascending aorta during primary CABG and OPCAB. One such device is the Symmetry aortic connector system (St. Jude Medical, Minneapolis, MN). These devices have obviated the need for partial occluding clamps for the construction of the proximal anastomoses and hence are extremely useful when the aorta is heavily calcified. We used this device successfully in two patients undergoing redo-OPCAB, where the proximal anastomosis was constructed on the descending aorta. In so doing, we also used the shortest possible length of vein graft since the descending aorta at that level was much closer than the left subclavian artery. This can be an additional factor in redo-operations where the availability of vein can be an issue. (J Card Surg 2004;19:51-53) [source]


A Prospective Pediatric Clinical Trial of Digital Music Players: Do They Interfere with Pacemakers?

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 1 2009
CHRISTINE C. CHIU M.Sc.
Background: There has been recent concern in the media about iPodÔ interference with pacemakers. We systematically tested two types of digital music players (DMP) on pacemaker or ICD function in children. Methods/Results: Patients were monitored by a 6-lead ECG and programmer telemetry. The pacemaker was tested in bipolar and unipolar sensing at normal and maximal sensitivities. The order of DMP tested was randomized. Each DMP was placed on top of the pacemaker pocket, put into "play" mode three times (5 seconds each), with and without programmer wand placed one cm adjacent to DMP. Pacemaker interference was defined as: pacing inhibition, inappropriate pacing, oversensing, or detection of high-rate episodes associated with the use of DMP. Of the 67 patients (mean age 12 ± 5 years), 62 had pacemakers and five had ICDs; 39 endocardial and 28 epicardial systems. Patients were tested with SansaÔ (67), iPodÔ 30 GB (51), and other DMPs (43). There was no evidence of interference with pacemaker function by any DMP under any of the study conditions (each performed in triplicate). Reproducible programmer telemetry interference was shown in 11 cases (Medtronic 6/47, St. Jude Medical 5/18, Guidant 0/2) related to use of iPodÔ (6), SansaÔ (1), or others (4). None of these were associated with any evidence of pacemaker malfunction. Conclusion: Interference with pacemaker function could not be shown with iPodÔ or MP3 players. No additional precaution beyond standard is necessary for patients with pacemakers when they are using these players. [source]


Right Ventricular Septal Pacing: A Comparative Study of Outflow Tract and Mid Ventricular Sites

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 10 2010
RAPHAEL ROSSO M.D.
Background: Prolonged right ventricle (RV) apical pacing is associated with left ventricle (LV) dysfunction due to dysynchronous ventricular activation and contraction. Alternative RV pacing sites with a narrower QRS compared to RV pacing might reflect a more physiological and synchronous LV activation. The purpose of this study was to compare the QRS morphology, duration, and suitability of RV outflow tract (RVOT) septal and mid-RV septal pacing. Methods: Seventeen consecutive patients with indication for dual-chamber pacing were enrolled in the study. Two standard 58-cm active fixation leads were passed to the RV and positioned in the RVOT septum and mid-RV septum using a commercially available septal stylet (model 4140, St. Jude Medical, St. Paul, MN, USA). QRS duration, morphology, and pacing parameters were compared at the two sites. The RV lead with less-satisfactory electrical parameters was withdrawn and deployed in the right atrium. Results: Successful positioning of the pacing leads at the RVOT septum and mid-RV septum was achieved in 15 patients (88.2%). There were no significant differences in the mean stimulation threshold, R-wave sensing, and lead impedance between the two sites. The QRS duration in the RVOT septum was 151 ± 14 ms and in the mid-RV septum 145 ± 13 ms (P = 0.150). Conclusions: This prospective observational study shows that septal pacing can be reliably achieved both in the RVOT and mid-RV with active fixation leads using a specifically shaped stylet. There are no preferences in regard to acute lead performance or paced QRS duration with either position. (PACE 2010; 33:1169,1173) [source]


Unusual ECG Pattern of Right Atrial Appendage Atrial Tachycardia in One Patient with Right Pneumonectomy

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 5 2010
KAZUYOSHI SUENARI M.D.
The right atrial appendage atrial tachycardia (RAA AT) has been previously reported as a rare site in focal AT. We report a patient with a history of a right pneumonectomy who underwent catheter ablation of the AT originating from the RAA. This RAA AT showed unusual P-wave morphology compared with previous reports. We describe the RAA AT following right pneumonectomy using a NavX system (St. Jude Medical, St. Paul, MN, USA). (PACE 2010; e46,e48) [source]


Segmental Pulmonary Vein Ablation: Success Rates with and without Exclusion of Areas Adjacent to the Esophagus

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 6 2008
KLAUS KETTERING M.D.
Background: Catheter ablation has become the first line of therapy in patients with symptomatic recurrent, drug-refractory atrial fibrillation (AF). The occurrence of an atrioesophageal fistula is a rare but serious complication after AF-ablation procedures. This risk is even present during segmental pulmonary vein (PV) ablation procedures because the esophagus does frequently have a very close anatomical relationship to the right or left PV ostia. The aim of the present study was to analyze whether the exclusion of areas adjacent to the esophagus does have a significant effect on the success rates after segmental pulmonary vein ablation procedures. Methods: Forty-three consecutive patients with symptomatic paroxysmal AF were enrolled in this study. In all patients, a segmental PV ablation procedure was performed. The procedures were facilitated by a 3D real-time visualization of the circumferential mapping catheter placed in the pulmonary veins using the NavXÔ system (St. Jude Medical, St. Paul, MN, USA; open irrigated tip ablation catheter; 43°C; 30 W). In 21 patients, a complete ostial PV isolation was attempted regardless of the anatomical relationship between the ablation sites and the esophagus (group A). In the remaining 22 patients, the esophagus was marked by a stomach tube and areas adjacent to the esophagus were excluded from the ablation procedure (group B). After discharge, patients were scheduled for repeated visits at the arrhythmia clinic at 1, 3, and 6 months after the ablation procedure. Results: The segmental pulmonary vein ablation procedure could be performed as planned in all patients. In group A, all pulmonary veins could be isolated successfully in 14 out of 21 patients (67%). A mean number of 3.7 pulmonary veins (SD ± 0.5 PVs) were isolated per patient. The main reasons for an incomplete PV isolation were: small diameter of the PVs, side branches close to the ostium, or poorly accessible PV ostia. In group B, all PVs could be isolated successfully in only 12 out of 22 patients (55%; P = 0.54). A mean number of 3.2 PVs (SD ± 0.9 PVs) were isolated per patient (P = 0.05). This was mostly due to a close anatomical relationship to the esophagus. The ablation strategy had to be modified in 16/22 patients in group B because of a close anatomical relationship between the left (n = 10) or right (n = 6) PV ostia and the esophagus. After 3 months, the percentage of patients free from an AF recurrence was not significantly different between the two groups (90% vs 95%; P = 0.61). After 6 months, there was no significant difference between the success rates either (81% vs 82%; P = 1.0). There were no major complications in both groups. Conclusions: The exclusion of areas adjacent to the esophagus results in a moderately higher percentage of incompletely isolated PVs. However, it does not have a significant effect on the AF recurrence rate during short-term and mid-term follow-up. [source]


Does Size Really Matter?

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 6 2008
A Comparison of the Riata Lead Family Based on Size, Its Relation to Performance
Background: Recently, the performance and safety of smaller diameter implantable cardioverter defibrillator (ICD) leads has been questioned. The purpose of this analysis was to determine the impact of size on lead performance and perforation rates by comparing the performance of 7 French (7F) and 8 French (8F) leads with similar design characteristics implanted by a single operator. Methods: Patients implanted with a Riata 1580 (8F) or 7000 (7F) series leads (St. Jude Medical, Sylmar, CA, USA) over a 2-year period were evaluated to compare performance and perforation rates. Results: There were 357 Riata 8F leads and 357 Riata 7F leads implanted in 714 patients. Follow-up ranged from 1 to 24 months. The 8F leads were implanted in the right ventricular apex more often than were 7F leads (129 or 37% vs 72 or 20%, P < 0.0001). Oversensing that did not result in therapy occurred in 2 pts (0.56%) with 8F leads and 1 pt. (0.28%) with a 7F lead (P = 0.56). Oversensing with therapy occurred once in both groups (0.28%, P = NS). One perforation occurred in each group (0.28%, P = NS). Both occurred in leads that were implanted in the right ventricular apex (P = 0.02). Conclusions: The performance of St. Jude Medical 7F and 8F Riata leads was similar. The incidence of lead-related adverse events was within or below the low end of published acceptable ranges for ICD lead perforation and sensing anomalies. Perforations were less likely to occur in leads that were implanted in nonapical positions. [source]


Three-Dimensional Mapping of Atypical Right Atrial Flutter Late after Chest Stabbing

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 3 2008
DANIEL STEVEN M.D.
We present the case of a female patient who previously underwent cardiac surgery for traumatic anterior right atrial perforation after a stabbing attack. Four years later the patient presented with right atrial common type flutter and isthmus ablation was performed subsequently. However, three years after isthmus ablation the patient was readmitted with atypical right atrial flutter. Electrophysiological study revealed persistent bidirectional isthmus block. Three-dimensional mapping (NavX, St. Jude Medical, St. Paul, MN, USA) demonstrated an incisional tachycardia with the critical isthmus at the border of the anterior area of scar in a close proximity to the superior tricuspid annulus. After ablation of this isthmus the patient was arrhythmia free after a follow-up of 9 months. This case illustrates that three-dimensional scar mapping may help to identify unusual isthmus sites that may be simultaneously responsible for both typical and atypical atrial flutter. [source]


Concerns about the Riata® ST (St. Jude Medical) ICD Lead

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1 2008
STEPHEN C. VLAY M.D.
No abstract is available for this article. [source]


Programmable Multiple Pacing Configurations Help to Overcome High Left Ventricular Pacing Thresholds and Avoid Phrenic Nerve Stimulation

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 12 2005
OSNAT GUREVITZ
Background: High left ventricular pacing (LVP) thresholds and phrenic nerve stimulation (PNS) are common problems with cardiac resynchronization (CRT). Newer systems capable of multiple LVP configurations may help overcome these problems without the need for reoperation. Methods: CRT systems capable of multiple LVP configurations (Guidant models H155 and H145) were implanted in 43 patients (study group). An additional 49 patients (control group) received CRT systems (Guidant, Medtronic, Biotronik, St. Jude Medical, various models) lacking this feature. Results: Overall, acute high (,2.5 V/0.5 ms) LVP thresholds were encountered in 13 (30%) of the study group, and 25 (50%) of control group patients (P = 0.03). PNS was encountered in 5 (12%) of the study group and 12 (24%) of control group patients (P = 0.13). All cases of high LVP thresholds and PNS in the study group were managed by switching to a different LVP configuration, while high thresholds remained in control group patients, and PNS was managed by replacing the lead. The CS lead was successfully placed in a lateral branch in 95% of study group, compared to only 77% of control group patients (P = 0.004). Conclusions: Multiple LVP configurations were clinically useful in a significant number of patients undergoing CRT system implantation by helping to overcome high LVP thresholds and PNS, and by providing more flexibility in placing the LV lead. [source]


Variability in Implantable Cardioverter Defibrillator Pulse Generator Longevity Between Manufacturers

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1p1 2003
PATRICK T. ELLINOR
ELLINOR, P.T., et al.: Variability in Implantable Cardioverter Defibrillator Pulse Generator Longevity Between Manufacturers.ICDs are used frequently to treat malignant ventricular arrhythmias. Despite the expanding role of these devices, little is known about the manufacturer variability in the performance of ICD generators. The purpose of this study is to explore the indications for ICD pulse generator replacement and to examine performance differences between the three major manufacturers of ICDs in the United States. The authors performed a retrospective review of ICD pulse generators that were implanted and replaced at Massachusetts General Hospital between February 1998 and March 2002. During the study period, 50 (7%) of the 707 devices in the study cohort were replaced. The most common indication for pulse generator replacement was related to battery performance followed by device recall, upgrade to a dual chamber device, and pulse generator malfunction. After exclusion of the recalled devices, a significantly higher number of pulse generators manufactured by St. Jude Medical (14/229) required replacement for battery depletion or prolonged charge times during the study period compared with devices from Guidant (2/220) or Medtronic (0/273),P = 0.003andP < 0.0001, respectively. This difference was attributable to reduced longevity in the Angstrom series of defibrillators. (PACE 2003; 26[Pt. I]:71,75) [source]


Improved Differentiation of the Ventricular Evoked Response from Polarization by Modification of the Pacemaker Impulse

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 12 2000
FRANK PROVENIER
The Autocapture feature, implemented in the Microny and Regency pacemakers of St. Jude Medical, continuously controls the effectiveness of ventricular stimulation by detection of the evoked response. Proper sensing of this signal depends on the magnitude of the polarization, which should be minimal. Therefore, the conjunctive use of low polarization electrodes is recommended. Further, the pacing impulse of these pacemakers has a biphasic waveform consisting of a stimulus followed by a fast discharge pulse. This study compares polarization of a modified pacing impulse with the default pacing impulse, and its effect on the ability to activate the Autocapture function when used with different types of electrodes. In 45 patients, acute measurements of the polarization and the evoked response were performed at random on the modified pacing impulses of a custom designed Regency and on the default stimuli of a standard Regency. The following bipolar leads were used: 20 Medtronic 4024 CapSure, 12 Pacesetter 1450T. and 13 Pacesetter 14701. Using the default pacing impulse, polarization and evoked response were significantly larger with the Medtronic 4024 CapSure compared to the low polarization leads. The polarization to evoked response ratio was more frequently acceptable for activation of the Autocapture with the Pacesetter leads. In all leads the modified pacing impulse was characterized bv significantly smaller polarization with the most prominent reduction in the Medtronic 4024 CapSure. The differences in the pacing impulse did not affect the evoked response. With the programmability of the fast discharge pulse, the requirements to activate the Autocapture function were fulfilled in 29 (94%) of 31 patients with the modified pacing impulse, compared to 22 (71%) of 31 patients with the standard pacing impulse. The modified pacing impulse decreased the "polarization to evoked response" ratio, and by that improved the conditions for activation of the Autocapture function. [source]


Laser Doppler Velocimetry and Flow Visualization Studies in the Regurgitant Leakage Flow Region of Three Mechanical Mitral Valves

ARTIFICIAL ORGANS, Issue 4 2001
Richard S. Meyer
Abstract: Streak line flow visualization and laser Doppler velocimetry (LDV) were conducted in the regurgitant leakage flow region of 3 mechanical heart valve types: CarboMedics, Medtronic Hall, and St. Jude Medical. Streak line flow visualization identified regions of high regurgitant flow, and LDV measurements were focused on those locations. Maximum regurgitant flow velocities after valve closure ranged from 0.7 to 2.6 m/s, and maximum Reynolds shear stress after valve closure ranged from 450 to 3,600 dyne/cm2. These data indicate that leakage flows can generate turbulent jets with elevated Reynolds stresses even in bileaflet valves. [source]