bluuebunny/crossref_metadata_2025 huggingface dataset:
Nonsustained, Asymptomatic Ventricular Tachycardia in Patients with Coronary Artery Disease: Prognosis and Incidence of Sudden Death of Patients Who Are Noninducible by Electrophysiological Testing
Authors: SCHMITT HEIKO , HURST TANJA , COCH MICHAEL , KILLAT HOLGER , WUNN BETTINA , WALDECKER BERND
Published: June 2006

The objective of this study was to determine the long‐term prognosis and the sudden death risk for patients with coronary artery disease and spontaneous nonsustained ventricular tachycardia who are not inducible by electrophysiological testing. Patients with coronary artery disease (CAD) who have spontaneous or inducible sustained ventricular tachycardia (VT) by electrophysiological testing are at increased risk of dying suddenly, and noninducibility is often considered as a favorable prognostic factor in their risk assessment. We studied 120 consecutive patients with CAD and nonsustained VT during Holter monitoring and followed the patients who were noninducible (n = 93) for 3.5 ± 1.6 years. None of these patients received antiarrhythmic therapy except β‐blockade. Overall mortality and the sudden death risk was assessed by the Kaplan‐Meier estimation. Predictors for overall mortality and sudden death were determined by multivariate analysis. During follow‐up, 23 of the 93 patients died, including 13 suddenly. Overall mortality was 9% after 1 year, 16% after 2years, and 21% after 3 years, respectively. The incidence of sudden death was 1 % after 1 year, 8% after 2 years, and 13% after 3 years, respectively. Patients with a LVEF ≤ 0.55 had an increased overall mortality risk with 15% after 1 year, 29% after 2 years, and 34% after 3 years (P = 0.012) and a risk of dying suddenly of 4% after 1 year, 12% after 2 years, and 18% after 3 years (P = NS), respectively. LVEF was the only independent predictor for overall mortality. In conclusion, patients with coronary artery disease and nonsustained ventricular tachycardia who are not inducible by electrophysiological testing have a moderate long‐term overall mortality risk. The risk of dying suddenly in this patient group is small but not negligible, especially in patients with impaired LVEF.
No Gender Differences in Pacemaker Selection in Patients Undergoing Their First Implantation
Authors: VAN LENNEP JEANINE E. ROETERS , ZWINDERMAN AEILKO H. , VAN LENNEP HENK W.O. ROETERS , VAN HEMEL NORBERT M. , SCHALIJ MARTIN J. , VAN DER WALL ERNST E.
Published: June 2006

Recent studies have indicated that women were less likely to receive sophisticated pacemaker devices than men. These differences could not be fully explained by demographic and clinical variables. The purpose of the present study was to assess whether a gender related difference might exist in pacemaker mode selection in patients undergoing their first implantation in The Netherlands. Records of first implants (n = 39,217) collected from 1988 through 1997 covering 95% of all implantations in The Netherlands. From this population 33,564 (85.6%) patients were included for final analysis. We observed no significant sex differences in pacemaker selection in patients with atrioventricular conduction disorders and bundle branch block. In patients with sick sinus syndrome, only very old women (≤ 85 years) had more atrial systems implanted than men of similar age (6.5% vs 3.5%), whereas men received more double chamber pacemakers (12.3% vs 10.3%) (P = 0.002). However, the relative distribution of physiological versus nonphysiological pacemakers in this subgroup was similar for men and women. In patients with chronic atrial fibrillation/flutter associated with bradycardia, sex differences were only apparent in the age group of 75–85 years; women received more dual chamber pacemakers (8,8% vs 5.3%) whereas men received more single chamber ventricular pacemakers (94.2% vs 89.8%) (P = 0.0011). With increasing age, sex differences in pacemaker selection were absent, but there was a considerable drop in implantation rate of dual chamber systems. Our study showed no major sex differences in the selection of pacemaker devices. Physicians select pacemaker devices by age rather than gender, which might be a rational choice.
Successful Laser‐Assisted Percutaneous Extraction of Four Pacemaker Leads Associated with Large Vegetations
Authors: NGUYEN KHANH‐TRANG , NEESE PAUL , KESSLER DAVID J.
Published: June 2006

A man with four endocardial pacemaker leads and two vegetations (1.5 cm and 1 cm) underwent successful percutaneous laser‐assisted lead extraction. Although this procedure was complicated by embolization to a left pulmonary arterial branch, the patient recovered without sequelae. This article reviews the literature on lead extraction associated with large vegetations.
Percutaneous Electrocatheter Technique for On‐Line Detection of Healed Transmural Myocardial Infarction
Authors: WARREN MARK , BRAGÓS RAMÓN , CASAS OSCAR , RODRÍGUEZ‐SINOVAS ANTONIO , ROSELL JAVIER , ANIVARRO INOCENCIO , CINCA JUAN
Published: June 2006

Healed myocardial infarction has been recognized by its particular tissue electrical impedance spectrum measured with intramural needle electrodes in animal models. The aim of this study was to develop a percutaneous approach for in vivo recognition of areas of healed myocardial infarction by measuring myocardial electrical impedance with an intracavitary contact electrocatheter. Electrical impedance (resistance and phase angle) of normal myocardium and of a 2‐month‐oid anterior transmural infarction were measured in nine chloralose anesthetized pigs by applying alternating currents from 1 kHz to 1 MHZ between a bipolar intracavitary catheter and a reference electrode placed on the epicardium (group I, n = 4) or on the precordium (group II, n = 5). Resistance of the infarcted myocardium was lower than that of healthy tissue at all current frequencies (ANOVA, P < 0.001) (i.e., at 1 kHz: 15 ± 4 Ω vs 50 ± 19 Ω in group I, and 64+ 13 Ω vs 76 ± 13 Ω in group II). Phase angle at 316 kHz best differentiated transmural infarction from normal tissue (group I: ‐2.5 ± 1.9 degrees vs ‐14.8 ± 4.6 degrees, P < 0.001; group II: +0.7 ±1.0 degrees vs ‐2.7 ± 1.4 degrees, P < 0.001). This study shows that analysis of myocardial impedance spectrum using a percutaneous intracavitary contact catheter approach permits on‐line recognition of areas of healed transmural myocardial infarction. This technique may be useful to optimize clinical application of energy sources (i.e., radiofrequency ablation, laser myocardial revascularization).
An Approach to Salvage a “Frozen” Pacing Lead
Authors: RAMICONE JAMES , LABIB ATEF , WISEMAN MARTIN , MACKALL JUDITH
Published: June 2006

We report our experience with the use of an orthopedic drill to remove “frozen” pacemaker leads from the connector block during pacemaker generator replacements. Three cases are reported in which the leads were salvaged successfully using this technique.
Ablation of Noninducible Idiopathic Left Ventricular Tachycardia Using a Noncontact Map Acquired from a Premature Complex with Tachycardia Morphology
Authors: FRIEDMAN PAUL A. , BEINBORN DOUGLAS A. , SCHULTZ JEFFREY , HAMMILL STEPHEN C.
Published: June 2006

We describe use of a novel noncontact system to permit mapping in a noninducible patient from a single premature ventricular complex with tachycardia morphology, thus guiding successful ablation after two previously failed conventional efforts. The instantaneous global electroanatomic map demonstrated fascicular macroreentry. Subsequent to ablation at an inferolateral site, there has been no clinical recurrence despite difficult arrhythmia control preprocedure. This case demonstrated that noncontact mapping can be used to create a potential map to guide successful ablation from a single premature ventricular complex in a patient with idiopathic left ventricular tachycardia that became noninducible at electrophysiological study.
Defibrillator Implantation Via the Iliac Vein
Authors: PINSKI SERGIO L. , BREDIKIS AUDRIUS J.
Published: June 2006

We describe a 23‐vear‐oId patient with idiopathic diluted cardiomyopathy in whom an implantable cardioverter defibrillator was implanted via the right external iliac vein. Addition of a subcutaneous patch was required to obtain an adequate safety margin for defibrillation.
Improvement of Exercise Tolerance by Single Lead VDD Pacemaker: Evaluation Using Cardiopulmonary Exercise Test
Authors: IJIRI HIROSHI , KOMORI SADAYOSHI , KOHNO ISAO , SANO SOICHI , YIN DONGFENG , TAKUSAGAWA MASAHIRO , IIDA TAKASHI , YAMAMOTO KIMIO , OSADA MITSURU , SAWANOBORI TAKAO , ISHIHARA TSUKASA , UMETANI KEN , TAMURA KOHJI
Published: June 2006

We used a Cardiopulmonary test to assess the physiological benefit of single lead VDD pacing in ten patients (six men, four women; aged 32–84 years, mean 69 years) with atrioventricular block. Maximal symptom‐limited treadmill exercise test using a ramp protocol was performed under VDD and VVIR or VVI pacing (VVI) in random sequence. The pacemaker was then programmed to the VDD mode, and Holter ECG was recorded in nine patients. Compared with findings during the VVI, the VDD mode had a greater chronotropic response (mean maximal heart rate, VDD 106 ± 17 beats/mm vs VVI 79 ± 19 beats/min, P = 0.03), and was associated with prolongation of exercise duration (VDD 11.2 ± 2.9 minute vs VVI 10.5 ± 3.1 minute; P = 0.01), and the onset of anaerobic threshold at a higher oxygen uptake (VDD 12.4 ± 3.4 mL/min per kilogram vs WI 10.0 ± 2.1 mL/min per kilogram; P < 0.01). Atriai sensing was recognized in almost all normal sinus P waves for all cases examined using Holter ECG. Thus, chronotropic response during exercise by VDD pacemaker improved exercise tolerance, indicating that a VDD pacemaker might be useful for patients requiring physical activity.
Atrioventricular Nodal Reentry Tachycardia: Slow Pathway Ablation Using the Transseptal Approach
Authors: SORBERA CARMINE , COHEN MARTIN , WOOLF PAUL , KALAPATAPU SRI RAMA
Published: June 2006

Four hundred twenty consecutive patients with symptomatic slow/fast atrioventricular nodal reentry tachycardia had attempted slow pathway radio frequency ablation. All patients had successful slow pathway ablation and no inducible tachycardia after ablation using the standard right‐sided approach except for three patients. The three unsuccessful patients had inducible slow/fast atrioventricular nodal tachycardia after attempted right‐sided posterior and inferoposterior anatomic ablative techniques and with slow pathway potential electrogram guidance. Lesions were also delivered linearly in the triangle of Koch and within the coronary sinus ostium. A transseptal puncture was performed and slow pathway ablation was obtained in each of these patients. Ablation was performed from the septal mitral valve annulus, anterior to the as of the coronary sinus and inferior to the His‐bundle catheter with elimination of slow pathway conduction. Prior to the ablation, two of the three patients exhibited initiation of tachycardia with a double fast/slow antegrade response, and all three patients had long AH intervals (mean 378 ms) during slow pathway conduction. These electrophysiological findings may be consistent with a large area of slow pathway conduction that may include the left atrial septum not approachable by conventional right‐sided ablative techniques. Slow pathway ablation to eliminate atrioventricular nodal reentry tachycardia at times may require a left atrial/transseptal approach when conventional right‐sided techniques are ineffective.
A Prospective Multicenter Study on the Safety of a Pacemaker with Automatic Energy Control: Influence of the Electrical Factor on Chronic Stimulation Threshold.
Authors: MADRID ANTONIO H. , OLAGÜE JOSÉ , CERCAS ALFONSO , DEL OJO JUAN LEAL , MUÑOZ FRANCISCO , MORO CONCEPCIÓN , SANZ OSCAR ,   PEACE investigators
Published: June 2006

The effectiveness and safety of a pacemaker with automatic control of capture was evaluated in 162 patients followed at 27 Spanish centers. The aim of our prospective, multicenter, and randomized trial was to determine the relationship between the voltage output of the pulse generator and the stimulation threshold. We randomized 162 patients (107 men, mean age 75 ± 12 years). We implanted a ventricular pacemaker model Regency SR+ or SC+ with Pacesetter's low polarization bipolar leads Membrane E 1450. The patients were randomized to receive Autocapture or not; group I (81 patients) Autocapture On, pulse output automatically adjusted and group II (81 patients) Autocapture Off, fixed output parameters (3.9 V, 0.37 ms). We performed a 6‐month follow‐up measuring stimulation threshold by means of the VARIO test and Autocapture test, evoked response signal, and R wave signal. The mean R wave was 15.77 ± 3.5 mV at the end of the follow‐up for group I, and 14.91 ± 6.8 mV for group II (P = NS). The measured evoked response at the end of the follow‐up was 9.25 mV in Group I and 8.48 mVin Group II (P = NS). The stimulation threshold was not different between groups. The current density created with the voltage and pulse width used in this study (± 3.9 V and 0.37 ms) at the tip of this electrode during the maturation process had no influence on the development of the chronic detection and stimulation thresholds.
Peak Endocardial Acceleration Reflects Heart Contractility Also in Atrial Fibrillation
Authors: BOMBARDINI TONINO , GAGGINI GUIDO , MARCELLI EMANUELA , PARLAPIANO MARIO , PLICCHI GIANNI
Published: June 2006

Previous studies demonstrated that peak endocardial acceleration (PEA) in sinus rhythm is related to LV dP/dtmax. Until now, PEA was never evaluated during R‐R interval variations in AF. The aim of this study was to establish the behavior of PEA in AF and the relationship of PEA versus LV dP/dtmax. Six sheep (65 ± 6 kg) were instrumented with a LV Millar catheter and with an accelerometer lead. AF was induced and PEA, LV dP/dtmax, and ECG were monitored. AF persisted for 5 ± 1.3 minutes. From sinus rhythm to AF, the heart rate went from 92 ± 3 to 130 ± 35 beats/mm (P < 0.05), LV dP/dtmax from 684 ± 18 to 956 ± 344 mmHg/s (P = NS) and PEA from 0.82 ± 0.06 to 0.94 ± 0.33 g (P = NS). The correlation between PEA and LV dP/dtmax was significative in sinus rhythm (r = 0.7, P < 0.05) and in AF (r = 0.8, P < 0.05). A positive relationship was found between the preceding interval and PEA (r = 0.4 ± 0,07, P < 0.05) and LV dP/dtmax (r = 0.61 ± 0.08, P < 0.05), while a negative one was found between the prepreceding interval and both PEA (r =− 0.39 ± O.11.P < 0.05) and LV dP/dtmax (r =− 0.64 ± 0.05, P < 0.05). At the onset of AF, LV dP/dtmax and PEA showed similar changes: beat‐to‐beat correlation between PEA and LV dP/dtmax was high. As for LV dP/dtmax, PEA is positively related to the preceding interval and negatively related to the prepreceding interval. These data confirm that PEA reflects heart contractility also during AF and hold promise for the use of this sensor in therapeutic implantable devices.
Dispersion of QT Intervals: A Measure of Dispersion of Repolarization or Simply a Projection Effect?
Authors: DI BERNARDO DIEGO , LANGLEY PHILIP , MURRAY ALAN
Published: June 2006

QT interval dispersion may provide little information about repolarization dispersion. Some clinical measurements demonstrate an association between high QT interval dispersion and high morbidity and mortality, but what is being measured is not clear. This study was designed to help resolve this dilemma. We compared the association between different clinical measures of QT interval dispersion and the ECG lead amplitudes derived from a heart vector model of repolarization with no repolarization dispersion whatsoever. We compared our clinical QT interval dispersion data obtained from 25 subjects without cardiac disease with similar data from published studies, and correlated these QT dispersion results with the distribution of lead amplitudes derived from the projection of the heart vector onto the body surface during repolarization. Published results were available for mean relative QT intervals and mean differences from the maximum QT interval. The leads were derived from Uijen and Dower lead vector data. Using the Uijen lead vector data, the correlation between measurements of dispersion and derived lead amplitudes ranged from 0.78 to 0.99 for limb leads, and using the Dower values ranged from 0.81 to 0.94 for the precordial leads. These results show a clear association between the measured QT interval dispersion and the variation in ECG lead amplitudes derived from a simple heart vector model of repolarization with no regional information. Therefore, measured QT dispersion is related mostly to a projection effect and is not a true measure of repolarization dispersion. Our existing interpretation of QT dispersion must be reexamined, and other measurements that provide true repolarization dispersion data investigated.
A Cosmetic Approach for Pectoral Pacemaker Implantation in Young Girls
Authors: ROSENTHAL ERIC
Published: June 2006

Pectoral placement of pacemaker generators, combined with use of a redundant intravascular lead portion, reduces the need for endocardial lead advancement during growth in children. While the use of small generators and submuscular pockets has contributed to cosmetic acceptability, the conventional subclavicular incision may occasionally form a keloid scar that is unacceptable in young girls. A modified implantation technique was used in five girls (age 2.6–13.3 years) during implantation of VDD (n = 2), VVIR (n = 2), and DDDR (n = 1) pacemakers. A 5‐cm incision was made in the axilla along the line of the pec‐toralis major and dissection was continued below the muscle to create a pocket for the generator. Subclavian vein puncture was performed from the axillary incision and beneath the pectoralis major muscle using standard or extra long needles with a needle guard. Peel away sheaths were used for lead positioning. The generator was placed in the submuscular pocket and the wound closed with absorbable sutures. At follow‐up, pacemaker function was excellent and neither the scars nor pacemakers were visible from the front. In conclusion, the axillary incision with direct subclavian vein puncture from below the pectoralis major muscle offers the advantages of pectoral pacemaker implantation through a single cosmetic incision.
Ventricular Pacing Failure After a Single Oral Dose of Pilsicainide in a Patient with a Permanent Pacemaker and Paroxysmal Atrial Fibrillation
Authors: NUMATA TETSUYA , ABE HARUHIKO , NAGATOMO TOSHIHISA , KOHSHI KIYOTAKA , NAKASHIMA YASUHIDE
Published: June 2006

A single oral dose of pilsicainide, a Class Ic antiarrhythmic drug, is a widely used and highly effective therapy for termination of recent onset atrial fibrillation. We report on a patient in which ventricular pacing failure occurred immediately after a single oral dose of pilsicainide. It did not exhibit a parallel relationship between the change in the pacing threshold and plasma concentration of pilsicainide, and the recovery period for the ventricular pacing threshold was longer than that of the plasma concentration of pilsicainide in this patient. Careful attention should be paid when a single oral dose of pilsicainide for termination of recent onset atrial fibrillation is used in patients with permanent pacemakers.
Implantation of a Cardiac Resynchronization System for Idiopathic Dilated Cardiomyopathy in a Patient with Persistent Left Superior Vena Cava Using an Experimental Lead for Left Ventricular Stimulation
Authors: LYON XAVIER , KAPPENBERGER LUKAS
Published: June 2006

A persistent left superior vena cava (PLSVC) was discovered at the implantation of a cardiac resvnchronization system in a woman with an idiopathic dilated cardiomyopathy. Standard leads were used to obtain right ventricular and right atrial (RA) stimulation according to a formerly described technique. The left ventricle was stimulated through the posterolateral vein of the heart by a novel lead design to be used over a guidewire for placement. Despite expected difficulties in this anatomic situation, the research lead was positioned in 23 minutes.
Successful Radiofrequency Catheter Ablation of Left Ventricular Tachycardia Following Surgical Correction of Tetralogy of Fallot
Authors: FUKUHARA HITOO , NAKAMURA YOSHIHIDE , TASATO HIROSHI , TANIHIRA YUKO , BABA KIYOSHI , NAKATA YOUHEI
Published: June 2006

A 13‐year‐old boy had recurrent ventricular tachycardia following surgical correction of tetralogy of Fallot. Pharmacological management with multiple an‐tiarrhythmic drugs failed, and the patient underwent electrophysiological evaluation. A reentrant tachycardia involving a slowly conducting region in the left ventricular outflow tract was demonstrated. We performed radiofrequency catheter ablation after identifying the essential components of the reentrant circuit. The ventricular tachycardia could no longer be induced and did not recur spontaneously during a 13‐month follow‐up.
DDD Pacing and Interatrial Conduction Block: Importance of Optimal AV Interval Setting
Authors: PARRAVICINI UMBERTO , MEZZANI ALESSANDRO , BIELLI MASSIMO , DI CAMILLO TITO , PARDO NICOLÒ FRANCHETTI , IRAGHI GABRIELE , ZENONE FRANCO , ZANETTA MARCO
Published: June 2006

The case of a 83‐year‐old patient undergoing DDD pacemaker implantation for sick sinus syndrome with postimplant detection of advanced interatrial conduction block is described. At nominal AV interval programming values (175 ms), absence of P wave following an atrial spike was observed, and the presence of an interatrial conduction disturbance was demonstrated by a Doppler transmitral flow pattern analysis and transesophageal ECG recording. AV interval lengthening up to 300 ms resulted in proper timing of atrial and ventricular contractions. Awaiting for conclusive data about biatrial pacing, interatrial conduction blocks can be managed in some cases by proper programming of conventional DDD systems.
Soluble L‐Selectin and Neutrophil Derived Oxidative Stress After Pacing Induced Myocardial Ischemia in Chronic Stable Coronary Artery Disease
Authors: GIANNITSIS EVANGELOS , TETTENBORN IVO , WIEGAND UWE , STIERLE ULRICH , KATUS HUGO A.
Published: June 2006

We studied the effect of atrial pacing induced myocardial ischemia on levels of soluble L‐selectin (sL‐selectin) and generation of neu‐trophil derived reactive oxygen species (ROS) in 10 patients with coronary artery disease (CAD) and sta‐ble angina and in six individuals without CAD. Myocardial ischemia was measured metabolically by lac‐tate sampling from the coronary sinus (CS) and arterial blood at each pacing step. Before each pacing step, at peak pacing and shortly after cessation, plasma concentrations of sL‐selectin and generation of ROS using the chemiluminescence method were measured in CS and femoral artery blood. Baseline sL‐selectin levels in CS samples were significantly lower in the CAD compared to the control group (547 ± 80 vs 836 ± 82 ng/mL, P = 0.03). At peak pacing, nine often patients with CAD developed myocardial ischemia (lac‐tate extraction ratio at rest 28%± 7%, at peak pacing ‐16%± 6%). In these patients, luminol‐enhanced chemiluminescence (CL, 0.88 ± 0.45 vs 3.9 ± 0.9 cpm × 105, P = 0.09) and levels of sL‐selectin (547 ± 80 vs 764 ± 86 ng/mL, P ‐ 0.03) from naive neutrophils increased significantly in CS blood suggesting a po‐tent in vivo activation of neutrophils. In control patients, incremental pacing caused neither myocardial ischemia nor a significant change of chemiluminescence or of sL‐selectin levels. In conclusion, myocar‐dial ischemia induced by pacing tachycardia is able to activate neutrophils in patients with chronic sta‐ble coronary artery disease leading to increased generation of ROS and shedding of L‐selectin into the coronary circulation.
Far‐Field QRS Complex Sensing: Prevalence and Timing with Bipolar Atrial Leads
Authors: BRANDT JOHAN , WORZEWSKI WOLF
Published: June 2006

Sensing of farfield QRS complexes through the atrial pacemaker lead may cause a number of pacemaker function disturbances, most of which are rarely seen with modern pulse generators. However, certain pulse generator algorithms will still be jeopardized by farfield QRS complex sensing. Intracardiac electrograms with markers were obtained by telemetry in 30 patients following implantation of a permanent bipolar atrial lead and a DDDR pulse generator. The occurrence and timing of farfield QRS complex sens‐ing was studied at different atrial amplifier sensitivity settings. With paced ventricular complexes, QRS sensing was documented in all 30 cases at the maximum atrial sensitivity (0.1 mV). The median QRS complex sensing threshold was 0.3 mV, and the sensing window at high atrial sensitivities was 67‐202 ms following the ventricular pacing impulse. In one case, QRS complex sensing was seen up to an atrial sensitivity of 1.5 mV. In 12 of 13 patients with 1:1 AV conduction, atrial sensing of spontaneously conducted ventricular complexes was seen (median sensing threshold 0.2 mV; the sensing window was–23 to 114 ms relative to the ventricular amplifier sensing event). Farfield QRS complex sensing was also found in all 12 patients in whom ventricular fusion complexes were obtained (median sensing threshold 0.2 mV; the window of sensing was 64‐187 ms after the ventricular pacing impulse). Constant or intermittent QBS complex sensing via the atrial bipolar lead was thus universally demonstrable. It occurred in only a mi nority (20%) of patients at a sensitivity of 0.5 mV or less. Knowledge regarding the timing of the over sensing as related to the atrial sensitivity setting may aid in the design of algorithms of future pacemak ers and cardioverter defibrillators.
Automatic Threshold Tracking Activation Without the Intraoperative Evaluation of the Evoked Response Amplitude
Authors: SCHUCHERT ANDREAS , VENTURA RODOLFO , MEINERTZ THOMAS
Published: June 2006

Automatic threshold tracking (Autocapture) controls the ampli‐tude of the pacing pulse and adjusts it to the actual pacing threshold. The algorithm is based on the proper detection of the evoked response (ER) amplitude after the pacing pulse. For this reason an intraoperative evaluation of ER and polarization is recommended. The aims of the study were to evaluate the ER signal and polarization and the performance of automatic threshold tracking without any intraoperative testing of the ER signal. In addition, the ER amplitude was correlated with the pacing threshold, pacing impedance, spontaneous R wave amplitude, and with the clinical data. The study included 60 patients who received the VVIR pacemaker Regency connected to the Membrane E 1450/1452 pacing lead (St. Jude‐Pacesetter). At implantation, a pacing threshold < 0.7 V at 0.5 ms was achieved in all patients. EH and polarization were assessed for the first time at hospital predischarge testing. Follow‐up measurements were conducted at month 1, 3, and 6. The ER amplitude at hospital discharge was 8.4 ± 4.2 mV and in‐creased to 9.4 ± 4.8 mV at the 6‐month follow‐up. The pacemaker recommended not to program auto‐matic threshold tracking on in one patient permanently and in three patients intermittently. The ER am‐plitudes were not differently distributed in men compared with women or in right‐sided compared to left‐sided implants. The correlation between age and the evoked response was r = 0.15. The correlation between ER amplitude and pacing threshold was r =–0.08, with pacing impedance r = 0.02, and with R wave amplitude r = 0.44. In conclusion, despite no operative evaluation of the ER amplitude being per formed, the mean ER amplitude was about 9 mV at 6‐month follow‐up.Automatic threshold tracking could be programmed on in 93% of the patients throughout the time. Neither the clinical data nor the con‐ventional electrical parameters help to predict patients who will have low ER amplitude or to optimize the ER signal at implantation.
Defibrillators in Nonischemic Cardiomyopathy Treatment Evaluation
Authors: KADISH ALAN , QUIGG REBECCA , SCHAECHTER I , ANDERSON KELLEY P. , ESTES MARK , LEVINE JOSEPH
Published: June 2006

The Defibrillators in Nonischemic Cardiomyopathy Treatment Evaluation (DEFINITE) is a multicenter randomized trial. Patients will have nonischemic Cardiomyopathy (LVEF ± 35%), a history of symptomatic heart fail‐ure and spontaneous arrhythmia (> 10 PVCs/hour or nonsustained ventricular tachycardia defined as 3‐15 beats at a rate of > 120 beats/min) on Holter monitor or telemetry within the past 6 months. Patients will be randomized to an implantable cardioverter defibrillator (ICD) versus no ICD. All patients will re‐ceive standard oral medical therapy for heart failure including angiotensin converting enzyme inhibitors and β‐blockers (if tolerated). Patients will be followed for 2‐3 years. The primary endpoint will be total mortality. Quality‐of‐life and pharmacoeconomics analyses will also be performed. A registry will track patients who meet basic inclusion criteria but are not randomized. We estimate an annual total mortality of 15% at 2 years in the treatment arm that does not receive an ICD. The ICD is expected to reduce mor‐tality by 50%. Approximately 204 patients will be required in each treatment group. Twenty‐five centers will be included in a trial designed to last an estimated 4 years.
Spontaneous Sustained Monomorphic Ventricular Tachycardia After Administration of Ajmaline in a Patient with Brugada Syndrome
Authors: BERMÚDEZ EDUARDO PINAR , GARCÍIA‐ALBEROLA ARCADIO , SÁNCHEZ JUAN MARTÍNEZ , MUÑOZ JUAN JOSÉ SÁNCHEZ , CHÁVARRI MARIANO VALDÉS
Published: June 2006

We present the case of a 13 year old boy with an episode of aborted sudden death, absence of structural heaii disease, and a characteristic ECG pattern of right bundle branch block with persistent ST‐segment elevation in the right precordial leads, in whom a monomorphic sustained ventricular tachycardia developed spontaneously after the administration of ajmaline. This effect may be related to an increased inhomogeneity of repolarization mediated by the drug and demonstrates the arrhythmogenic potential of Class I antiarrhythmic drugs in patients with Brugada syndrom
A Pilot Study of the Clinical Impact of Hand‐Carried Cardiac Ultrasound in the Medical Clinic
Authors: Croft Lori B. , Duvall W. Lane , Goldman Martin E.
Published: June 2006

Background: Small, hand‐carried ultrasound devices have become widely available, making point‐of‐care echocardiograms (echos) accessible to all medical personnel as a means to augment and improve the increasingly inefficient physical examination. This study was designed to determine the clinical utility of hand‐carried echo by medical residents in clinical decision making. Methods: Nine residents underwent brief, practical echo training to perform and interpret a limited hand‐carried echo as an integral component of their office examination. The residents' hand‐carried echo consisting of four basic views to define left ventricular (LV) function and wall thickness, valvular disease, and any pericardial effusions was compared to one performed by a level III echocardiographer. Results: Seventy‐two consecutive medical clinic patients were enrolled with an average image acquisition time of 4.45 minutes. Residents obtained diagnostic images in 94% of the cases and interpreted them correctly 93% of the time. They correctly identified 92% of the major echo findings and 78% of the minor findings. Their diagnosis of LV dysfunction, valvular disease, and LV hypertrophy improved by 19%, 39%, and 14% with hand‐carried echo compared to history and physical alone. Management decisions were reinforced in 76% and changed in 40% of patients with the use of hand‐carried echo. Conclusion: This study demonstrates that it is possible to train medical residents to perform an effective and reasonably accurate hand‐carried echo during their physical examination, which can impact clinical management.
Phialemonium curvatum Prosthetic Valve Endocarditis with an Unusual Echocardiographic Presentation
Authors: Osherov Azriel , Schwammenthal Ehud , Kuperstein Raphael , Strahilevitz Jacob , Feinberg Micha S.
Published: June 2006

Phialemonium species, an opportunistic fungal pathogen rarely causes invasive disease, have been described as opportunistic infection agents in humans, mainly as a result of immunosuppression and very rarely involves the heart. We present a case of a patient with Phialemonium curvatum prosthetic aortic valve endocarditis with an unusual initial transesophageal echocardiography (TEE) presentation, illustrating the important role of repeat TEE for the proper diagnosis and management of infective endocarditis.
Diagnosis and Surgical Correction of Cor Triatriatum in an Adult: Combined Use of Transesophageal and Contrast Echocardiography, and a Review of Literature
Authors: Modi Kalgi A. , Annamali Senthilkumar , Ernest Kiel , Pratep C. Reddy
Published: June 2006

Background: Cor triatriatum is rarely found in adults and its diagnosis is mostly dependent on transesophageal echocardiogram. We present a case of an adult male with cor triatriatum and discuss our approach to diagnosis with a review of literature. Case: A 49‐year‐old male presented with progressive exertional dyspnea for the past two‐and‐half years. A transthoracic echocardiogram revealed a thin linear echo‐dense structure traversing the left atrium (LA). A transesophageal echocardiogram demonstrated a thin immobile membrane in the LA attached medially to the interatrial septum. No fenestration of the membrane was seen. A swirling spontaneous contrast was noted in the posterior chamber. Color Doppler did not reveal any flow across the membrane. A CT scan of the chest was unhelpful to differentiate extracardiac versus intracardiac origin. Contrast echocardiogram with Optison was performed, which showed a differential opacification of the two atrial chambers and delayed emptying of contrast into true LA establishing communication between the chambers. Left and right heart catheterization were performed with simultaneous pulmonary capillary wedge and left ventricular end diastolic pressure measurement, revealing a mean gradient of 17 mmHg. Surgical correction of the membrane was recommended. Intraoperatively, an orifice of 0.7 cm was identified in an eccentric position with mosaic pattern of continuous turbulent flow across the membrane by color Doppler. Discussion: Our case demonstrates the impact of contrast echocardiography in a situation where the transesophageal approaches were limited even with the aid of color Doppler.
Usefulness of Live/Real Time Three‐Dimensional Transthoracic Echocardiography in the Identification of Individual Segment/Scallop Prolapse of the Mitral Valve
Authors: Patel Vinod , Hsiung Ming Chon , Nanda Navin C. , Miller Andrew P. , Fang Ligang , Yelamanchili Pridhvi , Mehmood Farhat , Gupta Mohit , Duncan Kurt , Singh Anurag , Rajdev Sanjay , Fan Pohoey , Naftel David C. , McGiffin David C. , Pacifico Albert D. , Kirklin James K. , Lin Chang‐Chyi , Yin Wei‐Hsian , Young Mason‐Shing , Chang Chung‐Yi , Wei Jeng
Published: June 2006

In this report, we present 34 patients in whom surgical intervention was undertaken for severe mitral insufficiency due to mitral valve prolapse (MVP). Location and severity of MVP and regurgitation were assessed preoperatively by live/real time three‐dimensional transthoracic echocardiography and closely agreed with the surgical findings.
Impact of Effective Valvotomy in Mitral Stenosis on Pulmonary Venous Flow Pattern
Authors: Tatani Solange Bernardes , Campos Orlando , Moises Valdir Ambrosio , Fischer Claudio Henrique , Marcondes Jose Augusto Souza , Carvalho Antonio Carlos C. , De Paola Angelo Amato V.
Published: June 2006

Aims: Transesophageal Doppler echocardiography (TEE) is a useful tool to investigate pulmonary venous flow (PVF) velocity, which is altered in patients with mitral stenosis (MS). This study used TEE to analyze the variations in the PVF pattern after successful valvar dilatation in MS patients. Methods/Results: A total of 15 MS patients, mean age 27.2 years, underwent effective percutaneous balloon valvotomy (PBV). All were submitted to TEE before and after PBV. TEE assessed systolic (SPFV) and diastolic (DPFV) peak flow velocities and their ratio (SPFV/DPFV), time‐velocity integrals (STVI and DTVI) and their ratio, and diastolic flow deceleration (DFD). Valvotomy yielded statistically significant increases (P ≤ 0.05) in the SPFV: increase on average by 67% and STVI by 120%, as well as in the diastolic component: increased on average by 35%, DTVI by 33%, and DFD by 75%. Conclusion: TEE demonstrated that PBV induced a global increase in velocities of PVF, probably related to improvement of left atrial emptying.
Preload Independence of Isovolumic Relaxation Flow Propagation Velocity
Authors: Voon Wen‐Chol , Su Ho‐Ming , Yen Hsueh‐Wei , Lin Tsung‐Hsien , Lai Wen‐Ter , Sheu Sheng‐Hsiung
Published: June 2006

To evaluate whether isovolumic relaxation flow propagation velocity (IRFPV) is independent of preload alterations, 41 healthy subjects (35 ± 7 years) were included for Doppler examinations at three different positions, i.e., supine, Trendelenburg, and reverse Trendelenburg. A positional difference was detected in the peak velocity of the transmitral early diastolic flow wave (P = 0.012) and the peak velocities of both early (P = 0.004) and late (P = 0.007) diastolic mitral annular velocity waves. In contrast, there was no positional difference in the early diastolic inflow propagation velocity or IRFPV. In conclusion, IRFPV is a preload‐independent Doppler parameter.
Mitral Annular Systolic Velocity Reflects the Left Atrial Appendage Function in Mitral Stenosis
Authors: Çaylý Murat , Kanadaşi Mehmet , Demir Mesut , Acartürk Esmeray
Published: June 2006

Background: Left atrial appendage (LAA) dysfunction is an independent predictor of thromboembolism in mitral stenosis (MS). Objectives: To investigate whether there is a relation between annular velocities obtained by tissue Doppler imaging and LAA function and to determine if the annular velocities can predict the presence of the inactive LAA in MS. Methods: Eighty‐five MS patients and 80 healthy controls were evaluated by transthoracic echocardiography and all patients underwent transesophageal echocardiography. The annular systolic (S‐wave) and diastolic (E‐ and A‐waves) velocities were recorded. Inactive LAA was defined as LAA emptying velocity <25 cm/sec. Patients were divided into three groups; group I (n = 43): sinus rhythm (SR) and LAA emptying velocity ≥25 cm/sec, group II (n = 15): SR and LAA emptying velocity <25cm/sec and group III (n = 27): atrial fibrillation. Results: Thrombus was detected in 12 patients and spontaneous echo contrast (SEC) was detected in 48 patients. Both S‐wave and peak LAA emptying velocities were decreasing, while SEC frequency and density were increasing from group I to group III. There was a positive correlation between LAA emptying and S‐wave velocities (P < 0.001, r = 0.682). Multivariate regression analysis showed that only S‐wave is the independent predictor of inactive LAA (P = 0.001, odds ratio = 0.143, 95% CI = 0.047–0.434). In patients with SR, the cutoff value of S‐wave was 13.5 cm/sec for the prediction of the presence of inactive LAA (sensitivity: 95.3%, specificity: 93.3%). Conclusions: S‐wave is an independent predictor of inactive LAA and a useful parameter in estimating inactive LAA in MS with SR.
Feasibility and Clinical Impact of Live Three‐Dimensional Echocardiography in the Management of Congenital Heart Disease
Authors: De Castro Stefano , Caselli Stefano , Papetti Federica , Ventriglia Flavia , Giardina Arianna , Cavarretta Elena , Di Angelantonio Emanuele , Marcantonio Andrea , Igual Perez Florinda D. , Pandian Natesa G. , Marino Bruno , Fedele Francesco
Published: June 2006

Background: Precise assessment of congenital heart lesions requires inferential evaluation from multiple two‐dimensional echocardiographic images (2DE). The aim of our study was to assess the usefulness of transthoracic live three‐dimensional echocardiography (3DE) in the evaluation of congenital heart disease. Methods: Eighty‐two patients (from 4 months to 31 years, mean age 12 ± 7.5, 38 males and 44 females), known to have congenital heart lesions, prospectively underwent both 2DE and 3DE. Conventional data acquisition by 2DE and “full volume” 3DE acquisition (apical four chambers, parasternal long and short axes, subcostal windows) were carried out by two independent and blinded operators. Data derived from 3DE were compared to 2DE, and 3DE results were graded into three categories: (A) new findings not seen on 2D echo studies, but not critical to therapeutic decision making; (B) additional anatomic information useful in therapeutic decision making; and (C) information equivalent to 2D echo studies. Results: Two out of 82 patients (2%) were excluded because of suboptimal 3DE images. In comparison with 2DE studies, 3DE was graded A in 23 patients (29%), B in 28 patients (35%), and C in 29 patients (36%). In the patients with group B results, atrial and ventricular septal defects, endocardial cushion defects, and l‐transposition of great vessels were the most represented pathologies in which 3DE aided medical or surgical therapeutic options. While the new findings in group A did not influence therapy, they defined the whole spectrum of abnormalities in those patients. In patients who fell under group C results, 3DE provided a direct realistic display of the pathology detected by 2DE. Conclusions: Our study demonstrates that live 3DE, easily performed at the bedside, provides incremental information on patients with a variety of congenital heart lesions. In the clinical scenario, it clarifies the pathology in all its dimensions, particularly in complex lesions with the incremental information having impact on therapeutic decision making.
Fibrosing TB Mediastinitis Presenting as a Superior Vena Cava Syndrome: A Case Presentation and Echocardiogram Correlate
Authors: Esquivel Lidiette , Diaz‐Picado Heiner
Published: June 2006

A 49‐year‐old woman developed a chronic obstruction of the superior vena cava (SVC) as a complication of mediastinal tuberculosis. Echocardiography findings are presented along with the cavography. Symptoms disappeared after stenting the fibrosed SVC. Transesophageal echocardiogram findings led to the condition's final resolution.
Recurrent Strokes in a Young Patient with Papillary Fibroelastoma: A Case Report and Literature Review
Authors: Dehnee Abed E. , Brizendine Steven , Herrera Cesar J.
Published: June 2006

Since the introduction of echocardiography the diagnosis of papillary fibroelastomas (PFEs) in living patients has increased. They are second most common after myxomas representing 10% of cardiac tumors. The present case is of a patient with recurrent cerebrovascular accidents and documented protein S deficiency who continued to stroke despite adequate anticoagulation. Mitral valve PFE was suspected on echocardiography and confirmed at surgical excision. Two large studies published in the last decade describe the echocardiographic and clinical characteristics of PFEs which although are histologically benign, may present with a clinical course of devastating consequences owing to its strategic location within the cardiac structures. Echocardiography, particularly transesophageal echocardiography (TEE), provides the necessary anatomical resolution and detail to ascertain location, extent of involvement, and hemodynamic implications. Tissue diagnosis is based on characteristic histopathological features of avascular fronds lined by endothelial cells, containing varying amounts of elastin. The echocardiographic characteristics along with treatment options are reviewed.
Noncatheter‐Associated Vegetative Phlebitis of the Superior Vena Cava Presenting with Multiple Lung Abscesses
Authors: Farvid Ali , Goel Manisha , Varadarajan Padmini , Pai Ramdas G.
Published: June 2006

We present a patient with a large vegetation in the superior vena cava (SVC) presenting with multiple staphylococcal lung abscesses. We believe that this is the first reported case of vegetative phlebitis of the SVC without a history of central venous catheter line. Our case emphasizes the need for careful imaging SVC using transesophageal echocardiography in bacteremic patients even in the absence of a central catheter.
Evaluation of Peripheral Vascular Endothelial Function with a Portable Ultrasound Device
Authors: Alsheikh‐Ali Alawi A. , Ouda Husam Z. , Pandian Natesa , Karas Richard H. , Kuvin Jeffrey T.
Published: June 2006

Endothelial function can be assessed noninvasively by imaging the brachial artery with ultrasound before and during reactive hyperemia. However, the standard ultrasound equipment typically used for this purpose is limited by size and expense of the machinery. In this study, we compared the ability of a portable ultrasound device to standard ultrasound equipment to visualize the brachial artery for purposes of assessing peripheral vascular endothelial function. The portable device provided comparable imaging of the brachial artery at rest and during hyperemia to that of standard ultrasound technology. These findings support the feasibility of noninvasive evaluation of peripheral endothelial function in the ambulatory setting.
The Impact of Marathon Running Upon Ventricular Function as Assessed by 2D, Doppler, and Tissue‐Doppler Echocardiography
Authors: Oxborough David , Shave Robert , Middleton Natalie , Whyte Gregory , Forster Jan , George Keith
Published: June 2006

The impact of prolonged exercise upon right ventricular (RV) function is poorly understood and to date no studies have utilized tissue‐Doppler imaging (TDI). Thirty‐five marathon runners (age range 18–50 years) volunteered for the study. Two‐dimensional, pulsed Doppler, and TDI studies were performed one day before and immediately following race completion. Right and left ventricular (LV) longitudinal TDI myocardial velocities were acquired from the tricuspid annulus and mitral annulus, providing velocity data during systole (S′), early diastole (E′), and late diastole (A′). Transtricuspid and transmitral, early diastolic (E), and late diastolic (A) velocities and ratios were assessed using conventional pulsed‐wave Doppler. RV and LV fractional area changes (FAC) were calculated from RV and LV end‐diastolic and end‐systolic areas recorded from 2D scans in a subsample (n = 23). RV myocardial velocities were unchanged pre‐post race in S′ (21.1 ± 2.7 to 21.7 ± 4.5 cm s−1, P > 0.05), reduced in E′ (23.3 ± 3.5 to 19.9 ± 5.3 cm s−1, P < 0.05), increased in A′ (19.1 ± 3.6 to 23.7 ± 6.8 cm s−1, P < 0.05) with a resultant decline in E′/A′ (1.28 ± 0.36 to 0.94 ± 0.45, P < 0.05). This pattern of data was mirrored in the LV. Similarly both pulsed‐Doppler tricuspid and mitral E/A ratios decreased from pre‐ to postrace (P < 0.05). FAC for the RV and LV were unaltered postrace (P > 0.05). The impact of differing age, finishing time (173–330 min), hemodynamic loading and heart rate upon RV and LV function pre‐ to postrace was negligible. In conclusion, TDI and 2D data, for both the RV and LV demonstrated little change in systolic function after a marathon race. Conversely, a reduction in diastolic function was observed in both ventricles for which a mechanism has yet to be deduced.