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Right bundle branch block pattern during right ventricular permanent pacing: Is it safe or not?  [cached]
Okan Erdogan,Feyza Aksu
Indian Pacing and Electrophysiology Journal , 2007,
Abstract: The present case report describes a patient with dual chamber pacemaker whose surface ECG demonstrated paced right bundle branch block pattern suggesting a malpositioned ventricular lead in the left ventricle. However, diagnostic work-up revealed that the lead was appropriately located in the right ventricular apex. Diagnostic maneuvers and clues for differentiating safe right bundle branch block pattern during permanent pacing are thoroughly revisited and discussed within the article.
Long-term safety and efficacy of right ventricular outflow tract pacing in patients with permanent pacemakers  [cached]
Okan Erdogan,Meryem Aktoz,Armagan Altun
Anadolu Kardiyoloji Dergisi , 2008,
Abstract: Objective: The aim of the present study was to investigate long-term safety and change in pacing parameters of right ventricular outflow tract (RVOT) pacing. Methods: This prospectively designed controlled clinical study comprised patients in Group 1 (n= 16) and Group 2 (n= 16) who were paced in RVOT and right ventricular apex (RVA), respectively, and were selected from patients with permanent pacemakers who were routinely followed up at our pacemaker clinic. Commercially available active fixation leads were used in all patients. Pacing parameters were compared at implant and long-term follow-up visits. Statistical analyses were performed using Pearson Chi-Square, nonparametric Mann-Whitney U and Wilcoxon Signed Ranks tests.Results: The mean duration of follow-up was 38.3±18.0 months for RVOT and 30.4±20.0 months for RVA (p=0.255). Impedance values, pacing thresholds and R wave amplitudes measured at implant and last pacemaker check did not significantly differ between RVOT and RVA pacing groups. There was no lead dislodgment or any other procedure related complication during follow-up. Conclusion: Right ventricular outflow tract pacing site is safe and pacing impedance and threshold values are comparable with conventional RVA pacing in the long-term.
Permanent Pacing in Patients with Recurrence of Symptoms and Relapse of Left Ventricular Obstruction at Midcavity Level after Alcohol Septal Ablation  [PDF]
Vasil Velchev,Arman Postadzhiyan,Dobri Hazarbasanov,Bojidar Finkov
International Journal of Vascular Medicine , 2012, DOI: 10.1155/2012/757501
Abstract: Treatment of symptom recurrence after initially successful alcohol septal ablation (ASA) in hypertrophic obstructive cardiomyopathy (HOCM) when accompanied by relapse of intracavitary left ventricular pressure gradient (LVG) is guided by the underlying mechanism. We describe our experience with permanent pacing in three patients with relapse of both LVG and symptoms 7 to 12 months after successful ASA. Even though pressure gradient recurrence was observed at midventricular level, we were able to achieve symptomatic improvement and LVG reduction after right ventricular apex pacing in all three cases. The effect on symptoms was long lasting—the 6-month followup echo-stress tests confirmed good exercise capacity and lack of provocable LVG. We found pacing to be a safe and effective treatment option in this clinical scenario. Based on our overall observations, we propose pacing as a niche treatment for patients with recurrence of LVG at midventricular level after ASA. 1. Introduction Alcohol septal ablation (ASA) is becoming a popular treatment choice for symptomatic patients with hypertrophic obstructive cardiomyopathy (HOCM) and resting left ventricular outflow tract obstruction gradient (LVOTG) above 50?mmHg.The recurrence of symptomatic LVOTG is approximately 10 percent in the first 2 years after ASA [1, 2]. Current hypotheses to explain this recurrence include possible incomplete remodeling of the septum due to imprecise location of the iatrogenic lesion, a small infarct size because of suboptimal ethanol tissue concentration and an underestimation of existent surgical pathology such as massive calcification of the mitral ring [2–4]. To the best of our knowledge, late recurrence of symptoms due to “migration” of obstruction to midcavity level following ASA has not been described in the literature. Therapeutic options for symptomatic patients with high residual LVOTG after ASA include surgery, repeat ASA, permanent pacing, and medical therapy. It is reasonable to speculate that permanent pacing has a synergistic effect on LVOTG after ASA and could be attempted before deciding on a repeat ASA or surgical myectomy. Here we present our experience with permanent pacing in three patients with HOCM who had recurrence of symptoms and LVG after initially successful alcohol septal ablation. Sixty-one patients with HOCM who remained symptomatic despite medical treatment underwent alcohol septal ablation at our institution between October 2004 and October 2007. Only patients with typical systolic anterior motion (SAM) and invasively measured LVOTG >50?mmHg at rest
Permanent Parahisian Pacing
Eraldo Occhetta,Miriam Bortnik,Paolo Marino
Indian Pacing and Electrophysiology Journal , 2007,
Abstract: Right Ventricular Apical permanent pacing could have negative hemodynamic effects. A physiologic pacing modality should preserve a correct atrio-ventricular and interventricular synchronization. This can be obtained through biventricular pacing, left ventricular pacing, or from alternative right ventricular pacing sites. Direct His Bundle Pacing (DHBP) was documented as reliable and effective for preventing the desynchronization and negative effects of right ventricular apical pacing. It is, however, a complex method that requires longer average implant times, cannot be carried out on all patients and presents high pacing thresholds. On the contrary, the parahisian pacing, with simpler feasibility and reliability criteria, seems to guarantee an early invasion of the His-Purkinje conduction system, with a physiological ventricular activation, very similar to the one that can be obtained with direct His bundle pacing. We present our experience on 68 patients who underwent a permanent right ventricular pacing in hisian/parahisian region, for advanced AV block and narrow QRS. In the first 17 patients we performed a double-blind randomized controlled study, with two 6-months cross-over periods in parahisian and apical pacing, documenting a significant improvement of NYHA class, exercise tolerance, quality of life score, mitral and tricuspidal regurgitation degree, and interventricular mechanical delay. In the subsequent 51 patients, in a mean follow of 21 months/patient, the pacing threshold remained stable (0.7±0.5 V implant; 0.9±0.7 V follow-up; p=0.08). The ejection fraction maintained medium-long term stable values, confirming the fact that the parahisian pacing can prevent deterioration of the left ventricular function. Parahisian pacing, therefore, has proven to be a reliable method, easy to apply and effective in preventing the negative effects induced by non-physiological right ventricular apical pacing.
Establishment of a canine model of cardiac memory using endocardial pacing via internal jugular vein
Li Yue-Chun, Ge Li-Sha, Guang Xue-Qiang, Chen Peng, Wu Lian-Pin, Yang Peng-Lin, Tang Ji-Fei, Lin Jia-Feng
BMC Cardiovascular Disorders , 2010, DOI: 10.1186/1471-2261-10-30
Abstract: Twelve Beagle dogs underwent placement of a permanent ventricular pacemaker mimicking the use of pacemakers in humans and induction of cardiac memory by endocardial ventricular pacing.Cardiac memory was achieved in 11 of 12 attempts overall. Procedural mortality due to cardiac tamponade (n = 1) occurred in the first attempt. The T-wave memory persisted for 96 ± 17 minutes and 31 ± 6 days in the short-term and long-term cardiac memory groups, respectively. There were no significant differences in the heart rate, blood pressure and echocardiographic parameters in the animals between before and after ventricular pacing in the short-term and long-term cardiac memory groups. No significant pathologic changes with the light microscopy were found in the present study in all dogs.The model does require surgery but is not as invasive as an open-chest model. This canine model can serve as a useful tool for studying mechanisms of cardiac memory."Cardiac memory" (CM) is characterized by persistent but reversible T-wave inversion related to abnormal activation of the ventricle such as ventricular pacing, transient left bundle branch block, ventricular preexcitation, and ventricular tachycardia[1-4]. Ventricular pacing alters the activation sequence of ventricular depolarization, which in turn alters the repolarization sequence. The repolarization change is manifested electrocardiographically by T wave change. Following the return to sinus rhythm after an interval of abnormal ventricular depolarization, the T wave vector persists in tracking the vector angle and amplitude of the QRS complex that characterized the paced state. The T-wave memory may persist for minutes to months after either short or long periods of ventricular pacing and will be described as short-term or long-term CM, respectively. However, the exact time period required to separate short- and long-term CM is still unknown.CM has clinical impact in that its ST-T- wave changes may mimic those of coronary ischemia,
The effect of atrial pacing on left ventricular diastolic function and BNP levels in patients with DDD pacemaker  [cached]
Zeynep Apal?,Serdar Bayata,Murat Ye?il,Erdin? Ar?kan
Anadolu Kardiyoloji Dergisi , 2010,
Abstract: Objective: We aimed to investigate the effect of atrial pacing on left ventricular diastolic function and brain natriuretic peptide (BNP) levels in patients with DDD pacemaker.Methods: Thirty patients with complete atrio-ventricular (AV) block and DDD pacemaker were included. All patients had normal left ventricular systolic function. Echocardiographic diastolic function parameters (transmitral and tissue Doppler velocities during early (E and E’) and late (A and A’) filling) and NT-pro-BNP levels were evaluated prospectively during atrial sensing and pacing periods. Echocardiographic data were compared with paired sample t test and NT-pro-BNP levels were compared with Wilcoxon test.Results: Echocardiographic E/A, E’/A’, E/E’ ratios were calculated as 0.72±0.34, 0.61±0.21 and 8.76±2.58 during atrial sensing period. Same parameters were found as 0.71±0.23, 0.64±0.16 and 8.93±3.16 respectively during atrial pacing period. Echocardiographic left ventricular diastolic function parameters were not significantly different during atrial pacing and atrial sensing periods. Median plasma NT-pro-BNP levels were measured as 142 pg/ml (min-max 47-563 pg/ml) and 147 pg/ml (min-max 33-1035 pg/ml) during atrial sensing and pacing periods respectively. These levels were not significantly different (p=0.86).Conclusion: The result of this study has shown that, atrial pacing has not any additional detrimental effect on left ventricular diastolic function parameters in paced patients with normal left ventricular systolic function.
Assessment of Ventricular Pacing in the Setting of an Institutional Improvement Program: Insights into Physiological Pacing
Antoine Kossaify, Sylvana Zoghbi and Paul Milliez
Clinical Medicine Insights: Cardiology , 2012, DOI: 10.4137/CMC.S8925
Abstract: Background: Excessive ventricular pacing is known to be detrimental. The purpose of this study was to assess ventricular pacing in the setting of an institutional improvement program in order to decrease unnecessary pacing. Method: This cross-sectional single-center study performed in a university hospital assessed 80 consecutive patients attending for a cardiac electronic device (pacemaker or cardioverter defibrillator) check. Forty percent of ventricular pacing was set as the cutoff level beyond which pacing was considered excessive. Results: Three patients were excluded. Forty-six (59.7%) patients (group 1) had more than 40% ventricular pacing and 31 (40.3%) patients (group 2) showed ventricular pacing less than 41%. In group 1, corrective action was successful in 27 (58.7%) patients, but 19 (41.3%) continued to have ventricular pacing over 40% and were discussed accordingly. An improvement program was established at the institution in order to decrease unnecessary ventricular pacing. Conclusion: Unnecessary ventricular pacing was encountered in many of the patients in this study, corrective actions were performed, and an institutional improvement project was set up as a consequence.
One-year cardiac morphological and functional evolution following permanent pacemaker implantation in right ventricular septal position in chagasic patients
Silva Júnior, Otaviano da;Maeda, Paula Mayumi;Borges, Maria Candida Calzada;Melo, Celso Salgado de;Correia, Dalmo;
Revista da Sociedade Brasileira de Medicina Tropical , 2012, DOI: 10.1590/S0037-86822012000300012
Abstract: introduction: the septal position is an alternative site for cardiac pacing (cp) that is potentially less harmful to cardiac function. methods: patients with chagas disease without heart failure submitted to permanent pacemaker (pp) implantation at the clinics hospital of the triangulo mineiro federal university (uftm), were selected from february 2009 to february 2010. the parameters analyzed were ventricular remodeling, the degree of electromechanical dyssynchrony (dem), exercise time and vo2 max during exercise testing (et) and functional class (nyha). echocardiography was performed 24 to 48h following implantation and after one year follow-up. the patients were submitted to et one month postprocedure and at the end of one year. results: thirty patients were included. patient mean age was 59±13 years-old. indication for pp implantation was complete atrioventricular (av) block in 22 (73.3%) patients and 2nd degree av block in the other eight (26.7%). all patients were in nyha i and no changes occurred in the et parameters. no variations were detected in echocardiographic remodeling measurements. intraventricular dyssynchrony was observed in 46.6% of cases and interventricular dyssynchrony in 33.3% of patients after one year. conclusions: the findings of this work suggest that there is not significant morphological and functional cardiac change following pacemaker implantation in septal position in chagasic patients with normal left ventricular function after one year follow-up. thus, patients may remain asymptomatic, presenting maintenance of functional capacity and no left ventricular remodeling.
Biventricular pacing and heterogeneity of ventricular repolarization in heart failure patients
Lucio Santangelo,Vincenzo Russo,Ernesto Ammendola,Ciro Cavallaro
Heart International , 2010, DOI: 10.4081/hi.2006.27
Abstract: Objective: The aim of our study was to evaluate the effect of cardiac resyncronization therapy (CRT) on QT dispersion (QTd), JT dispersion (JTd) and transmural dispersion of repolarization (TDR), markers of heterogeneity of ventricular repolarization in a study population with severe heart failure. Methods and Results: Fifty patients (43 male, 7 female, aged 60.2 ± 3.1 years) suffering from congestive heart failure (N = 39 NYHA class III; N = 11 NYHA class IV) as a result of coronary artery disease (N = 19) or of dilated cardiomyopathy (N = 31), sinus rhythm, QRS duration >130 ms (mean QRS duration >156 ± 21 ms), an ejection fraction < 35%, left ventricular end-diastolic diameter >55 mm, underwent permanent biventricular DDDR pacemaker implantation. A 12-lead standard electrocardiogram was performed at baseline, during right-, left-, and biventricular pacing and QTd, JTd and TDR were assessed. Biventricular pacing significantly reduced QTd (73.93 ± 19.4 ms during BiVP vs 91 ± 6.7 ms at sinus rhythm, p = 0.004), JTd (73.18 ± 17.16 ms during BiVP vs 100.72 ± 39.04 at baseline p = 0.003), TDR (93.16 ± 15.60 vs 101.55 ± 19.08 at baseline; p<0.004), as compared to sinus rhythm. Right ventricular endocardial pacing and left ventricular epicardial pacing both enhanced QTd (RVendoP 94 ± 51 ms, p<0.03; LVepiP 116 ± 71 ms, p<0.02) and TDR (RVendoP 108.13 ± 19.94 ms; p<0.002; LVepiP 114.71 ± 26.1; p<0.05).There was no effect on JTd during right and left ventricular stimulation. Conclusions: Biventricular pacing causes a statistically significant reduction of ventricular heterogeneity of ripolarization and has an electrophysiological antiarrhythmic influence on arrhythmogenic substrate of dilatative cardiomiopathy.
Temporary epicardial cardiac resynchronisation versus conventional right ventricular pacing after cardiac surgery: study protocol for a randomised control trial
Stuart J Russell, Christine Tan, Peter O'Keefe, Saeed Ashraf, Afzal Zaidi, Alan G Fraser, Zaheer R Yousef
Trials , 2012, DOI: 10.1186/1745-6215-13-20
Abstract: A multi-centred, prospective, randomised, single-blinded, intervention-control trial of temporary biventricular pacing versus standard pacing. Patients with ischaemic cardiomyopathy, valvular heart disease or both, an ejection fraction ≤ 35% and a conventional indication for cardiac surgery will be recruited from 2 cardiac centres. Baseline investigations will include: an electrocardiogram to confirm sinus rhythm and measure QRS duration; echocardiogram to evaluate left ventricular function and markers of mechanical dyssynchrony; dobutamine echocardiogram for viability and blood tests for renal function and biomarkers of myocardial injury- troponin T and brain naturetic peptide. Blood tests will be repeated at 18, 48 and 72 hours. The principal exclusions will be subjects with permanent atrial arrhythmias, permanent pacemakers, infective endocarditis or end-stage renal disease.After surgery, temporary pacing wires will be attached to the postero-lateral wall of the left ventricle, the right atrium and right ventricle and connected to a triple chamber temporary pacemaker. Subjects will be randomised to receive either temporary biventricular pacing or standard pacing (atrial inhibited pacing or atrial-synchronous right ventricular pacing) for 48 hours.The primary endpoint will be the duration of level 3 care. In brief, this is the requirement for invasive ventilation, multi-organ support or more than one inotrope/vasoconstrictor. Haemodynamic studies will be performed at baseline, 6, 18 and 24 hours after surgery using a pulmonary arterial catheter. Measurements will be taken in the following pacing modes: atrial inhibited; right ventricular only; atrial synchronous-right ventricular; atrial synchronous-left ventricular and biventricular pacing. Optimisation of the atrioventricular and interventricular delay will be performed in the biventricular pacing group at 18 hours. The effect of biventricular pacing on myocardial injury, post operative arrhythmias and renal fun
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