2005 Vol. 2, No. 2
It is a great honor to introduce the first arrhythmia issue of the Journal of Geriatric Cardiology. One goal of this Issue is to encourage discourse between East and West and to provide contrasts in management philosophies. The contributors representing some of the prominent in their field from the East and from the West do just this. Several contributors from the West have had prior experience in the East so they can understand cultural difference that might affect medical management approaches.
Atrial fibrillation (AF) is an extremely common condition in the elderly, with increasing prevalence around the world as the population ages. AF may be associated with serious health consequences, including stroke, heart failure, and decreased quality of life, so that careful management of AF by geriatric health care providers is required. With careful attention to anticoagulation therapy, and prudent use of medications and invasive procedures to minimize symptoms, many of the adverse health consequences of AF can be prevented.
Age-related physiological impairments of heart rate, blood pressure and cerebral blood flow, in combination with comorbid conditions and concurrent medications, account for an increased susceptibility to syncope in older adults. Common causes of syncope are orthostatic hypotension, neurally-mediated syncope (including carotid sinus syndrome) and cardiac arrhythmias. A high proportion of older patients with cardiovascular syncope present with falls and deny loss of consciousness. Patients who are cognitively normal and have unexplained falls should have a detailed cardiovascular assessment.
Ms. BP is an 83 year old white female with a long history of congestive heart failure (HF). She is now symptomatic with minimal exertion, has a left ventricular ejection fraction (LVEF) of 20%. Her CHF is due to hypertension (HTN) plus coronary artery disease (CAD) and she is on angiotensin converting enzyme inhibitor (ACEI), furosemide, digoxin, spironolactone, low dose beta blacker and nitrates. Her beta-natriuretic peptide (BNP) in clinic is 3030 pg/ml, heart rate (HR) 100, blood pressure (BP) 89/43. She has rales, jugular venous distention and pedal edema.An II/VI pansystolic murmur is appreciated over her entire precordium and an S3 is apparent. Her electrocardiogram (ECG) is shown in Figure 1 and reveals sinus tachycardia with a prolonged QRS duration of 159 milliseconds. Her husband brings in a new article about Bi-ventricular pacing and asks you if it will help her.
Sudden cardiac death (SCO) accounts for approximately 300,000 deaths each year in the United States. Ventricular fibrillation, as the initial event, had been reported in 65%-85% of these patients.1 An implantable cardioverter-defibrillator (ICD) is the single most effective life saving device to date. The advances in medicine and technology have led to wide spread utilization of defibrillators in developed countries. While there is general agreement that ICDs are indicated for secondary prevention of ventricular arrhythmias, it was not until recent years that primary prevention with an ICD was widely accepted.2 With the completion of the Multicenter Automatic Defibrillator Implantation Trial II (MADIT-II) and Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT), the indications for ICD implantation have expanded tremendously due to a better understanding of the natural history of cardiomyopathy and SCD and the limitation of current risk stratification methodologies and therapies. While ischemic cardiomyopathy is the single most important group of patients at high risk of SCD, accounting for 80% of SCD of those patients, other forms of cardiomyopathies and channelopathies have also emerged as important causes of sudden cardiac death. ICD' s have been proven to be an indispensable part of effective therapies for such patients. Unfortunately, subgroup analysis specifically on elderly patients was rarely performed in these trials. Extrapolation may be necessary to recommend when to implant ICD's in the elderly patients.
Objective To evaluate the effect of modified Maze lines plus pulmonary vein (PV) isolation created by radiofrequency catheter ablation (RFCA) on atrial wall guided by a novel geometry mapping system in the treatment of elderly patients with paroxysmal atrial fibrillation (PAF). Methods After regular electrophysiological study, transseptal punctures were achieved twice with Swartz LI and Rl sheaths. PV angiographies were conducted to evaluate their orifices and branches. A balloon electrode array catheter with 64 electrodes was put in the middle of the left atrium. Atrium geometry was constructed using Ensile 3000 Navx system. Two RFCA lesion loops and three lines (modified Maze) were created on left and right atrial walls. Each lesion point was ablated for 30 seconds with preset temperature 50 ;?and energy 30W. The disappearance or 80% decrease of the amplitude of target atrial potential and 10 to 20 !, decrease of ablation impedance were used as an index of effective ablation. Results A total of 11 patients (7 male and 4 female, mean age, 68.7±5.1 years) were enrolled. PAF history was 7.9±4.5 years. PAF could not be prevented by mean 3.1±1.6 antiarrhythmic agents in 6.3±3.4 years. None of the patients had complications with structural heart disease or stroke. Left atrial diameter was 41.3±3.6 mm and LVEF was 59.2±3.7 % on echocardiography. Two loops and three lines were completed with 67.8±13.1 (73-167) lesion points. Altogether 76-168 (89.4±15.3) lesion points were created in each patient. PAF could not be provoked by rapid burst pacing up to 600 beat per minute delivered from paroxysmal coronary sinus electrode pair. Complete PV electrical isolation was confirmed by three-dimensional activation mapping. Mean procedure time was 2.7±0.6 hours and fluoroscopy time was 17.8±9.4 minutes. Patients were discharged with oral aspirin and without antiarrhythmic agents. During follow up of 6.5±1.8 months, seven patients were PAF symptom free (63.6%). PAF attacks were decreased more than 70% in two patients (18.2%). PAF frequency did not change in another two patients (18.2%). Conclusions Ensile 3000 Navx guided modified Maze lines plus PV isolation on the atrial wall is safe and feasible in the elderly patienls. It has the advantages of exacl procedural endpoinl, shorter X-ray exposure, fewer complications and satisfied long-lerm effecl PAF conlrol.
Atrial fibrillation is the most common sustained arrhythmia and results in significant morbidity, especially in the elderly. The prevalence of atrial fibrillation increases dramatically with advancing age to almost 6 % in individuals older than 65 years. In fact, 84 % of people with atrial fibrillation are over 65 years of age.1 Additionally, the risk of stroke increases with advancing age, such that one-third of strokes in patients over the age of 65 are caused by atrial fibrillation.
Background and objectives Right ventricular apical (RVA) pacing has been reported impairing left ventricular (LV) performance. Alternative pacing sites in right ventricle (RV) has been explored to obtain better cardiac function. Our study was designed to compare the hemodynamic effects of right ventricular septal (RVS) pacing with RVA pacing. Methods Ten elderly patients with chronic atrial fibrillation (AF) and long RR interval or slow ventricular response (VR) received VVI pacing. The hemodynamic difference between RVS and RVA pacing were examined by transthoracic echocardiography (TTE). Results Pacing leads were implanted successfully at the RVA and then RVS in all patients without complication. The left ventricular (LV) parameters, measured during RVA pacing including left ventricular ejection fraction (LVEF), FS, stroke volume (SV) and peak E wave velocity (EV) were decreased significantly compared to baseline data, while during RVS pacing, they were significantly better than those during RVA pacing. However, after 3-6 weeks there was no statistical significant difference between pre- and post- RVS pacing. Conclusions The LV hemodynamic parameters during RVA pacing were significantly worse than baseline data. The short term LV hemodynamic parameters of RVS pacing were significantly better than those of RVA pacing; RVS pacing could improve the hemodynamic effect through maintaining normal ventricular activation sequence and biventricular contraction synchrony in patients with chronic AF and slow ventricular response.
The right ventricular (RV) apex is the traditional site to provide stable and reliable chronic ventricular pacing. Interest in alternate site pacing has grown since RV apical pacing has been associated with increased mortality and morbidity compared to normal atrio-ventricular conduction.1'4 Alternate pacing sites include the RV septum and outflow tract.
Heart failure (HF) is a major health problem for the geriatric population. In the United States, most of the 5 millions patients with HF are elderly.1 Seventy-five percent of HF hospitalizations occurred in patients older than 65 years and 50% in patients 75 years and older.1 In the Framingham population, the prevalence of HF increased eightfold among men from the fifth decade of life to the seventh decade.2 However, despite of considerable improvement in the treatment, the mortality of HF patients remained relatively constant between 1948 and 1997. Large epidemiologic surveys, such as the ongoing Framingham Study, have not documented any meaningful change in the HF patients' overall death rate. '-2-3 Between 1994 and 1997, in Ontario, approximately 33% of patients diagnosed with HF on the first admission died within 1 year.4-5 The mortality rate increased exponentially after age 65 in both men and women.4 Reduction in mortality demonstrated in randomized clinical trials of pharmacological agents, such as 3 -receptor blockers (BB) and angiotensin-converting enzyme inhibitors (ACEI), have been slow to be translated into substantial reductions of death and hospitalization rates in community-based HF populations.5 In more recent clinical trials, the addition of newer agents has had little, if any, impact on the high mortality of optimally treated patients.'-6 Accordingly, some authors have raised the concern that there may be limits to the benefits achievable through conventional pharmacological strategies.7-8 Therefore, there remains a need to develop novel, widely applicable, and cost-effective approaches in the management of HF.
Objective To investigate the prevalence of sleep-disordered breathing in elderly patients with permanent cardiac pacemaker implantation due to bradyarrhythmias, and the relationship between pacing mode and patients' sleep apnea-hypopnea index. Methods Forty-four elderly patients (>60 years) with cardiac pacemaker and their 44 controls matched for gender, age, body mass index and cardiovascular morbidity were studied using polysomnography or portable sleep monitoring device. Results Prevalence of sleep-disordered breathing (apnea-hypopnea index >5/h) was 44.7% and the mean apnea-hypopnea index was 8.2+4.1/h in the cardiac pacemaker group , which were significantly higher than those in control subjects (25% and 4. 6±2.4/h, respectively, P<0.01 and P<0.05). The mean apnea-hypopnea index of patients with ODD or AAI pacemaker was significantly lower than that of patients with VVI pacemaker. Conclusions Sleep-disordered breathing was more common in patients who had their cardiac pacemaker implanted due to bradyarrhythmias than in their matched controls. Compared with VVI pacing, ODD or AAI pacing may be more beneficial to patients with bradyarrhythmias and sleep-disordered breathing.
Objectives The cellular represser of El A-activated genes (CREG), a novel gene, was recently found to play a role in inhibiting cell growth and promoting cell differentiation. The purpose of this study was to obtain antibody against CREG protein and to study the expression of CREG protein in human internal thoracic artery cells (HITASY) which express different patterns of differentiation markers after serum withdrawal. Methods The open reading frame of CREG gene sequence was amplified by PCR and cloned into the pGEX-4T-l vector. Glutathione-S-transferase (GST)-CREG fusion protein was expressed in E.coli BL21 and purified from inclusion bodies by Scphacryl S-200 chromatography. Rabbits were immunized with the purified GST-CREG protein. Western blot analysis detected the expression of smooth muscle-specific markers (SM a-actin, Calponin). The localization of CREG protein was examined with immunohistochemistry staining and the protein expression level was analyzed by Western blot in HITASY cells after serum removal. Results It was confirmed by using endonuclcasc digesting and DNA sequencing that the PCR product of CREG was correctly inserted into the vector. The GST-CREG protein was purified with gel filtration chromatography. Polyclonal antibody against GST-CREG was obtained from rabbits. CREG protein immunohistochemistry staining displayed a perinuclear distribution in the cytoplasm of HITASY cells. Results from Western blot suggested that comparing with the untreated cells upregulation of CREG protein, SM a-actin and Calponin is induced respectively in HITASY cells after serum deprivation. Conclusions The specificity of polyclonal antibody against CREG was comfirmed. Using this antibody, the changes of CREG protein expression was observed in the process of phenotypic modulation of HITASY cells. These results provide basic understanding on the relationship of CREG gene
The aging of the population and improvements in outcomes after cardiovascular surgery have resulted in a worldwide growing demand of complex surgical intervention for elderly patients. We briefly review the up-to-date English-language literature with particular focus on cardiovascular surgery in elderly patients. With earlier referral, careful preoperative evaluation, strategic planning, and the continuing efforts in optimizing surgical techniques, operative mortality and morbidity following primary or reoperative coronary artery bypass grafting and valvular interventions are expected to fall in this high-risk patient subset. Importantly, accumulating evidence indicates that elderly patients may benefit from improved functional status and quality of life after cardiovascular surgical therapy.