Incidence of atrial high rate episodes after dual-chamber permanent pacemaker implantation and its clinical predictors

Atrial high rate episodes (AHRE) confers increased morbidity and mortality amongst patients with permanent pacemaker implantation (PPI). The incidence of AHREs and it's clinical predictors in Indian patients without prior history of atrial fibrillation (AF) are not well understood. A total of 100 dualchamber PPI patients, who had no prior history of AF, underwent pacemaker interrogation starting from a minimum of 1 month after implantation to detect any AHREs. The incidence of AHREs was 17% at a mean follow up 15.2 ± 7.5 months. Only right ventricular apical lead position was found to have an independent association with AHREs (OR: 3.50, 95% CI: 1.02e12.03; p ¼ 0.04).

A CASE REPORT OF SYMPTOMATIC COMPLETE HEART BLOCK DIAGNOSED AS KEARNS–SAYRE SYNDROME(KSS)

Kearns-Sayre syndrome (KSS) is a rare syndrome characterized by the triad of progressive external ophthalmoplegia, pigmentary retinopathy and cardiac conduction system disturbances; it is a mitochondrial encephalomyopathy with which usually presents before the patient reaches the age of 20. Here we present a case report of KSS who presented with symptomatic complete heart block.

Clinical, hemodynamic, echocardiographic, angiographic profiles and post-operative outcomes among DCRV patients from a tertiary care referral center in India

Background: This retrospective study of data from 2006 to 2018 at a tertiary care referral center in India aims to document the contemporary clinical and hemodynamic profile of patients who were diagnosed with double chamber right ventricle (DCRV) based on echocardiography and cardiac  catheterization. Patients were followed up and their outcomes were studied to document their short and long term outcomes.Methods: It is a retrospective observational study of patients diagnosed with DCRV in a tertiary care hospital in India. The diagnosis of DCRV was based on the following criteria: an echocardiographic diagnosis of DCRV with doppler evidence of a mid ventricular gradient; cardiac catheterization revealing a systolic pressure gradient between right ventricular inflow and outflow tracts; a right ventricular angiogram demonstrating an anomalous muscle bundle causing obstruction well below the infundibulum. All the patients were followed up for their long term outcomes.Results: All the patients underwent echocardiography and cardiac catheterization for confirmation of the diagnosis. Sixty percent of our patients presented during adulthood, which is very unusual presentation of this disease entity. Median age of our patient cohort was 23.5 years. Patients presenting during adulthood have atypical symptoms. Dyspnea was the most common presenting symptom in this study. Right ventricular hypertrophy (73.3%)and right bundle branch pattern (26.6%) were the common electrocardiographic findings in our patients. DCRV is commonly associated with other anomalies. Ventricular septal defect (VSD) was the commonest associated anomaly, which was seen in 80% of our patients. Mean gradient cross the anomalous muscle bundle was 67.5 mmHg. Three of our patients (20%) had no associated anomaly, which is very rare in DCRV. Eight patients underwent surgical correction with significant reduction in gradients in all and no perioperative mortality. Median follow up of 8 years showed no adverse outcomes and no progression of gradients.Conclusions: This study describes in detail the clinical profile, echocardiographic and angiographic identification of anomalous muscle bundles in DCRV patients, which will help the young readers in identifying this often missed diagnosis. It highlights the unusual presentation during adulthood with atypical symptoms in DCRV patients with excellent long-term outcomes on follow up.

Prevalencia de fibrilación auricular y factores predictores de su aparición en pacientes portadores de marcapasos bicamerales / Prevalence of atrial fibrillation and predictors of its occurrence in patients with dual-chamber pacemakers

Resumen Objetivos Evaluar la prevalencia de fibrilación auricular (FA) en pacientes portadores de marcapasos bicamerales (MB), las variables asociadas a su aparición y los cambios de conducta clínica que este hallazgo ha generado. Métodos Se incluyó prospectivamente a 500 pacientes ambulatorios portadores de MB. Se realizó interrogatorio sobre el MB. Se contactó a los médicos de cabecera ante la aparición de FA y luego se determinó si esta información resultaba en cambios de conducta terapéutica. Resultados La media de edad de la población fue de 77 años, con un 51% de hombres. Se detectó FA en un 13.2% de los pacientes. Esto generó modificaciones en el tratamiento en un 64.7% de ellos. En el modelo de regresión logística, a través de un análisis multivariado, se asociaron a la aparición de FA las siguientes variables: hipertensión arterial (OR = 2.62; IC 95% 1.01-6.8; p < 0.048), antecedente de FA (OR = 4.30; IC 95% 2.26-8.32; p < 0.001), enfermedad del nodo sinusal como causa de implante (OR = 2.09; IC 95% 1.09-3.97; p < 0.025) y la cantidad de series de extrasístoles supraventriculares detectadas (OR = 1.000033 por cada serie; IC 95% 0.000011-0.000055; p < 0.003). Una cantidad de series de extrasístoles supraventriculares igual o mayor de 77 en un control de marcapasos presenta un área bajo la curva de 0.81 para la detección de FA. Conclusión Se ha detectado una alta prevalencia de FA en pacientes portadores de MB. Este hallazgo condujo a importantes cambios en el tratamiento. Se han detectado 4 variables asociadas independientemente a la detección de FA.

Abstract Objectives To assess the prevalence of atrial fibrillation (AF) in patients with dual-chamber pacemakers (DP), determine the variables associated with development of AF and evaluate the changes in AF's management by physicians. Methods Five hundred patients with DP were prospectively included and interrogated. When AF was detected physicians in charge of the patient were warned. Changes in AF's management were evaluated. Results Mean age of the study population was 77 years, with 51% of men. AF was detected in 13.2% of patients. These findings led treatment changes in 64.7%. The variables analyzed by logistic regression model which were associated with the occurrence of AF were: arterial hypertension (OR = 2.62; CI 95% 1.01-6.8; P < .048), history of AF (OR = 4.30; CI 95% 2.26-8.32; P < .001), sick sinus syndrome as cause of device implantation (OR = 2.09; CI 95% 1.09-3.97; P < .025) and burden of supraventricular extrasystoles series(OR = 1.000033 per serie; CI 95% 0.000011-0.000055; P < .003.). Conclusion We have detected a high prevalence of AF in patients with DP. The diagnose of AF led to change in treatment. Four clinical variables increase the likelihood of developing this arrhythmia.

The influence and clinical significance of different pacing modes on central aortic pressure and augmentation index in non-smoking individuals / 天津医药

Objective To investigate the influence and clinical significance of single and dual-chamber pacing on central aortic pressure (CAP) and augmentation index (AI) in non-smoking individuals. Methods Totally, 83 non-smokers with pacemaker-implanted were consecutively enrolled in this study, and they were divided into three groups:dual-chamber pacemaker group (DDD, n=35), single-chamber pacemaker group (VVI, n=33) and control group (n=15). Heart rate (HR), CAP, AI, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured in three groups of patients. Finally, DDD pacing mode was turned into VVI pacing mode in patients of DDD group and the indexes were measured again. All of the indexes were recorded and analyzed. Results There were no significant changes in baseline characteristics and laboratory data between three groups (P>0.05). Left atrial diameters were significantly higher in VVI group than those of control group (P0.05). All of these indexes (CAP, AI and brachial BP) were significantly reduced after the pacing mode was changed (P<0.05). Conclusion In non-smokers, dual-chamber pacing mode can increase CAP and AI.

Cardiac Resynchronization Therapy Using a Dual Chamber Pacemaker in Patients with Severe Left Ventricular Dysfunction and a Left Bundle Branch Block

Through the use of a dual chamber (DDD) pacemaker, we achieved a cardiac resynchronization effect in a 51-year-old female patient who was transferred to our hospital from another hospital for an operation for three-vessel coronary artery disease. Her electrocardiogram showed a left bundle branch block (LBBB) and a prolonged QRS interval of 166 milliseconds. Severe left ventricle (LV) dysfunction was diagnosed via echocardiography. Coronary artery bypass grafting (CABG) was then performed. In order to accelerate left atrial activation and reduce the conduction defect, DDD pacing using right atrial and left and right ventricular pacing wires was initiated postoperatively. The cardiac output was measured immediately, and one and twelve hours after arrival in the intensive care unit. The cardiac output changed from 2.8, 2.4, and 3.6 L/min without pacing to 3.5, 3.4, and 3.5 L/min on initiation of pacing. The biventricular synchronization using DDD pacing was turned off 18 hours after surgery. She was transferred to a general ward with a cardiac output of 3.9 L/min. In patients with coronary artery disease, severe LV dysfunction, and LBBB, cardiac resynchronization therapy can be achieved through DDD pacing after CABG.

Anesthetic management of a patient with hypertrophic obstructive cardiomyopathy with dual-chamber pacemaker undergoing transurethral resection of the prostate.

We describe the anesthetic management of a patient with hypertrophic obstructive cardiomyopathy with dual-chamber pacemaker undergoing transurethral resection of the prostate. Anesthetic challenges included prevention and management of perioperative arrhythmias, maintenance of adequate preload, afterload and heart rate to relieve left ventricular outflow tract obstruction and considerations related to the presence of dual-chamber pacemaker and TURP. We recommend preoperative reprogramming of the DDD pacemaker, avoidance of magnet application during the procedure, application of electrosurgical unit current returning pad to the anterior aspect of the thigh, especially if monopolar cautery is used, use of central venous pressure line for estimation of preload and careful titration of anesthetic drugs to maintain stable hemodynamics.

A novel non invasive measurement of hemodynamic parameters: Comparison of single-chamber ventricular and dual-chamber pacemaker.

We carried out a cross sectional study to analyze hemodynamic parameters of single-chamber ventricular pacemaker compared with dual-chamber pacemaker by using thoracic electrical bioimpedance monitoring method (Physio Flow™) - a novel simple non-invasive measurement. A total of 48 consecutive outpatients comprised of 27 single chamber pacemaker and 21 dual chamber were analyzed. We measured cardiac parameters: heart rate, stroke volume index, cardiac output index, estimated ejection fraction, end diastolic volume, early diastolic function ratio, thoracic fluid index, and systemic parameters: left cardiac work index and systemic vascular resistance index. Baseline characteristic and pacemaker indication were similar in both groups. Cardiac parameters assessment revealed no significant difference between single-chamber pacemaker and dual-chamber pacemaker in heart rate, stroke volume index, cardiac index, estimated ejection fraction, end-diastolic volume, thoracic fluid index. There was significantly higher early diastolic function ratio in single-chamber pacemaker compared to dual-chamber pacemaker: 92% (10.2-187.7%) vs. 100.6% (48.7-403.2%); p=0.006. Systemic parameters assessment revealed significantly higher left cardiac work index in single-chamber group than dual-chamber group 4.9 kg.m/m² (2.8-7.6 kg.m/m²) vs. 4.3 kg.m/m² (2.9-7.2 kg.m/m²); p=0.004. There was no significant difference on systemic vascular resistance in single-chamber compared to dual-chamber pacemaker. Single-chamber ventricular pacemaker provides similar stroke volume, cardiac output and left cardiac work, compared to dual-chamber pacemaker. A non-invasive hemodynamic measurement using thoracic electrical bioimpedance is feasible for permanent pacemaker outpatients.

Improvement of minimizing ventricular pacing in dual chamber pacemaker / 中国实用内科杂志

The data from clinical studies have shown that conventional dual chamber pacing results in high percentages of right ventricular apical pacing,which causes electromechanical desynchronization and has been linked to an increased risk of heart failure and atrial fibrillation.Nowadays,we can use some special algorithms to minimize ventricular pacing,promote atrioventricular conduction and improve hemodynamics in patients with pacemakers.This review summarizes the genesis,some algorithms and clinical studies about minimizing ventricular pacing.