Can Right Ventricular Pacing be Useful in the Assessment of Cavo-tricuspid Isthumus Block?

Background

Cavo-tricuspid isthmus (CTI) block is currently assessed by coronary sinus (CS) pacing or low lateral and septal atrial pacing. Occasionally, CS catheterization through the femoral route can be difficult to perform or right atrial pacing can be problematic because of catheter instability or saturation of the atrial electrograms recorded near the catheter.

Objectives

Our aim was to evaluate the feasibility of assessing cavo-tricuspid isthmus block by means of right ventricular (RV) pacing in patients with ventriculo-atrial conduction, comparing it with CS pacing.

Methods

Circumannular activation was analyzed during CS and RV pacing in consecutive patients in sinus rhythm undergoing CTI ablation for typical atrial flutter. Patients without ventriculo-atrial conduction were excluded from the study. The linear lesion was created during RV pacing and split atrial signals on the ablation line were analyzed. CTI block was confirmed by analyzing local electrograms on the line of block and circumannular activation during CS and RV pacing.

Results

Out of 31 patients, 20 displayed ventriculo-atrial conduction (64%) and were included in the study. Before ablation, during RV stimulation, the collision front of circumannular activation shifted counterclockwise in contrast with the pattern observed during CS pacing. After ablation, circumannular activation was similar during CS and RV pacing, showing fully descending lateral right atrium activation, even if double potentials registered on the ablation line were less widely split during RV pacing than CS pacing (111±26 ms vs 128±30 , p=0.0001).

Conclusions

In patients with ventriculo-atrial conduction, tricuspid annulus activation during CS and RV pacing is similar, before and after CTI ablation. The occurrence of split atrial electrograms separated by an isoelectric interval registered on the line of block can be detected during CS or RV pacing. In patients with difficult CS catheterization via the femoral vein, before trying the subclavian or internal jugular route, if retrograde ventriculo-atrial conduction is present, RV pacing can be an easy trick to assess isthmus block.     

Reversion of thyrotoxic atrial fibrillation in hypothyroid state after radioiodine treatment.

Twenty patients with thyrotoxic Basedow's disease complicated by atrial fibrillation lasting more than one month despite treatment with antithyroidal drugs were treated with radioiodine supplemented with an antithyroidal drug or inorganic iodine. We classified the 20 patients on the basis of atrial fibrillation reversion into two groups, one with reversion (group I) and the other without reversion (group II). In all 12 patients in group I, T4 and T3 decreased to hypothyroid levels in 3.2 +/- 1.3 months, and one month later all patients had their sinus rhythm restored while T4 and T3 remained below normal (2.6 +/- 1.1 micrograms/dl and 77.9 +/- 34.4 ng/dl, respectively). Although T4 and T3 also decreased within 3.5 +/- 1.8 months in all 8 patients in group II, one month later, atrial fibrillation persisted while T4 and T3 (10.4 +/- 5.3 micrograms/dl and 157.7 +/- 67.5 ng/dl, respectively) rose significantly compared to those in group I (P less than 0.001 and P less than 0.01, respectively). For reversion of atrial fibrillation it is important that the onset of hypothyroidism is rapidly induced by radioiodine and that hypothyroidism continues for at least one month.     

A randomized trial to assess the impact of an antithrombotic decision aid in patients with nonvalvular atrial fibrillation: the DAAFI trial protocol [ISRCTN14429643]

Background

Surprisingly little information on symptoms of paroxysmal atrial fibrillation is available in scientific literature. Using questionnaires, we have analyzed the symptoms associated with arrhythmia attacks.

Methods

One hundred randomly-selected patients with idiopathic paroxysmal atrial fibrillation filled in a structured questionnaire.

Results

Psychic stress was the most common factor triggering arrhythmia (54%), followed by physical exertion (42%), tiredness (41%) coffee (25%) and infections (22%). Thirty-four patients cited alcohol, 26 in the form of red wine, 16 as white wine and 26 as spirits. Among these 34, red wine and spirits produced significantly more episodes of arrhythmia than white wine (p = 0.01 and 0.005 respectively). Symptoms during arrhythmia were palpitations while exerting (88%), reduced physical ability (87%), palpitations at rest (86%), shortage of breath during exertion (70%) and anxiety (59%). Significant differences between sexes were noted regarding swollen legs (women 21%, men 6%, p = 0.027), nausea (women 36%, men 13%, p = 0.012) and anxiety (females 79%, males 51%, p = 0.014).

Conclusion

Psychic stress was the commonest triggering factor in hospitalized patients with paroxysmal atrial fibrillation. Red wine and spirits were more proarrhythmic than white wine. Symptoms in women in connection with attacks of arrhythmia vary somewhat from those in men.     

Vagal effects on sinoatrial and atrial conduction studied with epicardial mapping in dogs: the influence of pacemaker shifts on the measurement of sinoatrial conduction time

The influence of pacemaker shifts on sinoatrial conduction time (SACT) was studied by investigating the effects of vagal stimulation on SACT and atrial conduction in anesthetized open-chest dogs. Isochronal maps were drawn from unipolar electrograms simultaneously recorded at 60 epicardial sites on the right atrial free wall and the inferior and superior vena cava. Vagal stimulation caused atrial conduction velocity to increase from 0.99 +/- 0.10 m/s (mean +/- SD) to 1.23 +/- 0.23 m/s (p less than 0.01), and the pacemaker to shift to lower positions along the superior vena cava - right atrial junction. As a result of the changes, the distances and the atrial conduction times from the stimulating and recording electrodes to the pacemaker site varied, and hence, the SACT values obtained indirectly by premature atrial stimulation varied. The isochronal maps were used to measure the atrial conduction times from stimulating to recording electrodes (a), from stimulating electrode to pacemaker site (b), and from pacemaker site to recording electrode (c). Indirect SACT was lengthened by vagal stimulation from 43 +/- 16 to 64 +/- 22 ms (p less than 0.02). After correcting by subtracting the atrial conduction time (b + c - a), these values became 26 +/- 6 ms (control) and 40 +/- 11 ms (vagal stimulation) (p less than 0.01). SACT values measured directly from the electrograms were 27 +/- 7 ms (control) and 42 +/- 10 ms (vagal stimulation) (p less than 0.01). Corrected indirect SACTs were closer to direct SACTs than were the uncorrected indirect SACTs.(ABSTRACT TRUNCATED AT 250 WORDS)     

Mechanoelectric feedback leads to conduction slowing and block in acutely dilated atria: a modeling study of cardiac electromechanics

Atrial fibrillation, a common cardiac arrhythmia, is promoted by atrial dilatation. Acute atrial dilatation may play a role in atrial arrhythmogenesis through mechanoelectric feedback. In experimental studies, conduction slowing and block have been observed in acutely dilated atria. In the present study, the influence of the stretch-activated current (I(sac)) on impulse propagation is investigated by means of computer simulations. Homogeneous and inhomogeneous atrial tissues are modeled by cardiac fibers composed of segments that are electrically and mechanically coupled. Active force is related to free Ca(2+) concentration and sarcomere length. Simulations of homogeneous and inhomogeneous cardiac fibers have been performed to quantify the relation between conduction velocity and I(sac) under stretch. In our model, conduction slowing and block are related to the amount of stretch and are enhanced by contraction of early-activated segments. Conduction block can be unidirectional in an inhomogeneous fiber and is promoted by a shorter stimulation interval. Slowing of conduction is explained by inactivation of Na(+) channels and a lower maximum upstroke velocity due to a depolarized resting membrane potential. Conduction block at shorter stimulation intervals is explained by a longer effective refractory period under stretch. Our observations are in agreement with experimental results and explain the large differences in intra-atrial conduction, as well as the increased inducibility of atrial fibrillation in acutely dilated atria.     

Diagnostic value of thyrotrophin releasing hormone tests in elderly patients with atrial fibrillation.

A prospective study was carried out to compare clinical and biochemical thyroid states with responses of thyroid stimulating hormone (TSH) to thyrotrophin releasing hormone (TRH) in elderly patients with either atrial fibrillation (n = 75; mean age (SD) 79.3 (6.0) years) or sinus rhythm (n = 73; mean age 78.4 (5.6) years) admitted consecutively to the department of geriatric medicine. No patient in either group had symptoms or signs of hyperthyroidism. Overall, the TSH responses to TRH did not differ significantly between the two groups. Ten (13%) of the patients with atrial fibrillation (of whom four had raised thyroid hormone concentrations) and five (7%) of the patients with sinus rhythm showed no TSH response to TRH while 26% of each group (20 and 19 patients, respectively) showed a much reduced response. Only one of 13 patients with apparently isolated atrial fibrillation showed no TSH response to TRH, and none of these 13 patients was hyperthyroid. In particular, three patients (two with atrial fibrillation and one with sinus rhythm) who showed no TSH response to TRH at presentation exhibited a return of TSH response to TRH at follow up six weeks later. In conclusion, reduced or absent TSH responses to TRH are common in sick elderly patients whether they have atrial fibrillation or sinus rhythm and whether they are euthyroid or hyperthyroid biochemically. An absence of response is therefore an uncertain marker of hyperthyroidism in these groups of patients, and diagnosis and ablative treatment should be based at least on the presence of raised circulating free triiodothyronine or free thyroxine concentrations, or both.     

Programmed atrial and ventricular stimulation in patients with mitral valve prolapse--a personal experience]

Electrophysiological tests were performed in 60 patients aged between 18 and 63 years (mean age 38 years), and divided into two groups: with mitral valve leaves prolapse syndrome, and without this abnormality, in whom no other heart disease was diagnosed. Refraction of the right atrium, atrio-ventricular node, and right ventricle was evaluated together with cardiac response to different types of electrostimulation. A supraventricular dysrhythmia (most frequently atrial fibrillation) has been produced in 17 patients (42.5%) with mitral valve leaves prolapse syndrome whereas in the control group the same was produced in 2 patients (10%). Programmed stimulation of the ventricles did not produce ventricular tachycardia in none patient of both groups. Multiple ventricular beats have been produced in 3 patients with mitral valve prolapse syndrome and pairs of ventricular beats in other 3 patients of this group. Results suggest that "arrhythmogenic tendency", especially supraventricular dysrhythmia is more frequent in patients with mitral valve prolapse syndrome than in the general population.     

Evaluation of Bachmann Bundle Pacing Versus Right Atrial Pacing in Prevention of Atrial Fibrillation After Coronary Artery Bypass Surgery

Background

In patients undergoing coronary artery bypass surgery (CABGS), occurrence of atrial fibrillation (AF) is common in the postoperative period and is associated with increased morbidity with longer intensive unit care (ICU) and hospital stay. Prevention with antiarrhythmic drugs is of limited success and associated with significant side effects. Therefore alternative approaches, such as Bachmann Bundle pacing, are required.

Methods and Results

154 consecutive patients, mean age 58±8.8 years, including 134 males and 20 females, were randomized to three groups; Group I : No pacing n= 54, Group II : RA pacing n= 52, Group III : Bachmann Bundle pacing n= 48. All the groups were well matched with regard to age, left atrial size, ejection fraction and use of beta blockers. Patients in Groups II and III were continually paced at a rate of 100 beats per minute (bpm) or at 10 bpm more than patients'' intrinsic heart rate. All the patients were monitored for 72 hours by telemetry and occurrence of AF was noted. Incidence of AF was 0% (none of 48 patients) in Group III as compared to 16.6% in Group I (9 of 54 patients) (p 0.003) and 12.5% in Group II (5 of 52 patients) (p 0.03). There was a trend towards shorter ICU stay in Group III (3.9 days) as compared to Group II (4.5 days) and Group I (4.1 days). Among the three groups, the reduction in mean P wave duration also was greater in Bachmann bundle paced group.

Conclusion

In patients undergoing CABGS, Bachmann bundle pacing is superior to right atrial / no pacing in the post operative period for preventing occurrence of AF and reducing ICU stay, commensurate with a reduction in mean P wave duration on surface ECG.     

Blood pressure and blood lipids in normotensive patients with diabetes mellitus type I with microalbuminuria]

The study involved 50 normotensive men (means age = 34 years) with diabetes mellitus type I (mean duration of the disease 14 years). Group I included 29 patients with normal albumin excretion with the urine (UAE below 30 mg daily), and group II-21 patients with microalbuminuria (UAE 30-300 mg daily). Both groups were similar in relation to the age and duration of diabetes mellitus. Blood cholesterol was significantly higher in patients of group II than in patients of group I (p = 0.02) similarly to blood triglycerides levels (p = 0.01). Mean arterial pressure was lower in patients of group I than that in patients of group II (94.3 +/- 7.0 vs 99.1 +/- 6.0 mm Hg; p = 0.01). HbA1c was positively correlated with blood cholesterol (p = 0.01) and blood triglycerides levels (p = 0.05).     

Transitions among atrial fibrillation, atrial flutter, and sinus rhythm during procainamide infusion and vagal stimulation in dogs with sterile pericarditis

The mechanism of atrial flutter and fibrillation induced by rapid pacing in 22 dogs with 3-day-old sterile pericarditis was investigated by computerized epicardial mapping of atrial activation before and after administration of agents known to modify atrial electrophysiologic properties: procainamide, isoproterenol, and electrical stimulation of the vagosympathetic trunks. Before the administration of any of these agents, a total of 30 episodes of sustained atrial flutter (greater than 1 min duration, monomorphic; regular cycle length, 127 +/- 12 ms, mean +/- SD) was induced in 15 out of 22 dogs and 9 episodes of unstable atrial flutter (duration, less than 1 min; cycle length, 129 +/- 34 ms; monomorphic, alternating with fibrillation) were induced in the remaining 7 preparations. In the latter, administration of procainamide transformed unstable atrial flutter and atrial fibrillation to sustained atrial flutter (cycle length, 142 +/- 33 ms; n = 9 episodes). During control atrial flutter, atrial maps displayed circus movement of excitation in the right atrial free wall with faster conduction parallel to the orientation of intra-atrial myocardial bundles. Vagal stimulation changed atrial flutter to atrial fibrillation in 32 of 73 trials; this was associated with acceleration of conduction in the lower right atrium, leading to fragmentation of the major wave front. Isoproterenol produced a 6-25% increase of the atrial rate in 6 out of 14 trials of atrial flutter and induced atrial fibrillation in 4. After procainamide, the reentrant pathway was lengthened and conduction was slowed further in the right atrium. Maps obtained during unstable atrial flutter showed incomplete circuits involving the right atrium. Following procainamide infusion, the area of functional dissociation or block was enlarged and a stable circus movement pattern, which was similar to the pattern seen in control atrial flutter, was established in the right atrium. We conclude that (1) the transitions among atrial fibrillation, atrial flutter, and sinus rhythm occur between different functional states of the same circus movement substratum primarily located in the lower right atrial free wall, and (2) the anisotropic conduction properties of the right atrium may contribute to these reentrant arrhythmias and may be potentiated by acute pericarditis.     

经食道超声心动图评估特发性房颤左心房左心耳的价值

目的:研究经食道超声心动图(TEE)评估特发性房颤左心房左心耳的临床价值。方法:选择自2015年1月到2016年8月在医院接受诊治的特发性房颤患者100例纳入本次研究,阵发性房颤92例,记为阵发性房颤组;持续性房颤8例,记为持续性房颤组。另选同期在医院进行健康体检的心功能正常志愿者90例作为对照组。利用TEE对受试者进行检查,对比房颤组与对照组的左心房及左心耳参数,是否含有自发性显影(LASEC)的房颤患者的左心房及左心耳参数,利用TEE分析对房颤患者的预后情况。结果:阵发性房颤组左心房的前后径和左右径,左心耳血流最大的排空速度(Lev)均明显小于对照组,左心耳的面积变化率及最大的充盈速度(Lfv)均明显大于对照组,差异有统计学意义(P0.05)。持续性房颤组左心房的前后径和左右径均明显大于对照组,左心耳的面积变化率、Lev及Lfv均明显小于对照组,差异有统计学意义(P0.05)。阵发性房颤组左心房的前后径和左右径均明显小于持续性房颤组,左心耳的面积变化率、Lev及Lfv均明显大于持续性房颤组,差异有统计学意义(P0.05)。有LASEC者左心房的前后径和左右径均明显大于无LASEC者,左心耳的面积变化率、Lev及Lfv均明显小于无LASEC者,差异有统计学意义(P0.05)。100例房颤患者中发现34例LASEC,占34.00%,其中有18例患者合并有左心耳血栓,占18.00%。总计有66例患者接受导管射频消融疗法,占66.00%,均未在术中及术后7d内出现血栓及栓塞并发症。结论:利用TEE对特发性房颤的患者左心房及左心耳进行评估,有利于更好的辅助患者的临床治疗,值得重视。     

The effect of bretylium tosylate on ventricular arrhythmias in patients with acute myocardial infarction]

Sixty three patients with the acute myocardial infarction, aged between 34 and 85 years, admitted to the Intensive Cardiological Care Unit during the first 12 hours following the infarction were randomly divided into two groups. Patients of group I (20 subjects) were treated with nitroglycerin and additional intravenous infusions of bretylium tosylate in the dose of 5 mg/kg administered every 6 hours for 48-72 hours. Patients of group II (33 subjects) were mainly treated with intravenous nitroglycerin. A type and incidence of the ventricular arrhythmias, conduction disorders in AV node, and hemodynamic complications were analysed during the first 72 hours. It was found that bretylium tosylate reduces the incidence of ventricular arrhythmias accompanying myocardial infarction but after 2-3 hours following its administration (p < 0.05). Therefore, bretylium tosylate should be administrated to patients with the acute myocardial infarction in combination with other rapidly acting anti-arrhythmic drug. Bretylium tosylate increases also the effectiveness of electric defibrillation in patients with ventricular fibrillation or ventricular tachyarrhythmia. No evidence of the effectiveness of bretylium tosylate on atrio-ventricular conduction and hemodynamic complications of myocardial infarction was found.     

Frequent Periodic Leg Movement During Sleep Is an Unrecognized Risk Factor for Progression of Atrial Fibrillation

Sleep apnea has been recognized as a factor predisposing to atrial fibrillation recurrence and progression. The effect of other sleep-disturbing conditions on atrial fibrillation progression is not known. We sought to determine whether frequent periodic leg movement during sleep is a risk factor for progression of atrial fibrillation. In this retrospective study, patients with atrial fibrillation and a clinical suspicion of restless legs syndrome who were referred for polysomnography were divided into two groups based on severity of periodic leg movement during sleep: frequent (periodic movement index >35/h) and infrequent (≤35/h). Progression of atrial fibrillation to persistent or permanent forms between the two groups was compared using Wilcoxon rank-sum test, chi-square tests and logistic regression analysis. Of 373 patients with atrial fibrillation (77% paroxysmal, 23% persistent), 108 (29%) progressed to persistent or permanent atrial fibrillation during follow-up (median, 33 months; interquartile range, 16-50). Compared to patients with infrequent periodic leg movement during sleep (n=168), patients with frequent periodic leg movement during sleep (n=205) had a higher rate of atrial fibrillation progression (23% vs. 34%; p=0.01). Patients with frequent periodic leg movement during sleep were older and predominantly male; however, there were no significant differences at baseline in clinical factors that promote atrial fibrillation progression between both groups. On multivariate analysis, independent predictors of atrial fibrillation progression were persistent atrial fibrillation at baseline, female gender, hypertension and frequent periodic leg movement during sleep. In patients with frequent periodic leg movement during sleep, dopaminergic therapy for control of leg movements in patients with restless legs syndrome reduced risk of atrial fibrillation progression. Frequent leg movement during sleep in patients with restless legs syndrome is associated with progression of atrial fibrillation to persistent and permanent forms.     

左房增大对起搏器术后的老年阵发性房颤患者再发房颤的影响

目的：探讨植入心脏起搏器的老年阵发性房颤患者再发房颤（包括无症状性房颤）发生率及左房容积指数对再发房颤的影响。方法：收集2012年1月-2013年12月在我院起搏器门诊长期随访且未服用抗心律失常药物的起搏器术后老年阵发性房颤患者148例,记录基线特征、超声心动图参数及随访期间内房颤发生情况。分别根据左房容积指数及房颤负荷进行分组,应用Cox回归分析探讨起搏器检测的再发房颤及房颤高负荷的危险因素。结果：患者平均随访时间为22.79个月,期间57.43%的患者再发房颤,22.97%的患者为房颤高负荷,15.54%的患者为无症状房颤。多因素Cox回归分析发现左房增大分别是再发房颤及房颤高负荷的独立危险因素。结论：左房容积指数是预测起搏器术后老年阵发性房颤患者房颤复发及房颤高负荷的独立危险因素。     

Paced QRS morphology predicts incident left ventricular systolic dysfunction and atrial fibrillation

Background

The prognostic significance of paced QRS complex morphology on surface ECG remains unclear. This study aimed to assess long-term outcomes associated with variations in the paced QRS complex.

Assessment of cardiac risk 10 days after uncomplicated myocardial infarction.

A total of 188 patients with uncomplicated acute myocardial infarction (long-term Norris prognostic index 3.2) were rapidly mobilised, underwent a symptom-limited exercise test around the day of discharge from hospital (day 10), and returned to work at a median of six weeks after the acute event. The incidence of cardiac death six months, one year, and three years after infarction was 2.7%, 4.5%, and 7.3% respectively, and the corresponding figures for recurrent heart attacks were 3.4%, 8.2%, and 18.5% respectively. The risk of recurrence of heart attack was predicted by three variables assessed at discharge--namely, a history of classical effort angina (p less than 0.01), radiological heart failure (p less than 0.05), and angina induced by the exercise test (p less than 0.05). The presence of any of these risk factors defined a group of patients with a sevenfold risk of recurrent heart attacks within six months of the initial acute infarct. It is concluded that these risk factors identify a group of patients with a high risk of recurrence early after infarction, in whom vigorous secondary prophylaxis is desirable.     

The association between arterial stiffness and left ventricular filling pressure in an apparently healthy Korean population

Aims

Transesophageal echocardiography (TEE) is the gold standard for the detection of thrombi in patients with atrial fibrillation (AF) before undergoing early electrical cardioversion (CV). However, TEE generates inconclusive results in a considerable number of patients. This study investigated the influence of contrast enhancement on interpretability of TEE for the detection of left atrial (LA) thrombi compared to conventional TEE and assessed, whether there are differences in the rate of thromboembolic events after electrical cardioversion.

Methods

Of 180 patients with AF (51 females, 65.2±13 years) who were referred to CV, 90 were examined with native imaging and contrast enhancement within the same examination (group 1), and 90 were examined with native TEE alone and served as control (group 2). Cineloops of the multiplane examination of the LA and LA appendage (LAA) were stored digitally before and, in group 1, after intravenous bolus application of a transpulmonary contrast agent. Images of group 1 were assessed offline and the diagnosis of LA thrombi was made semi-quantitatively: 1= thrombus present; 2=inconclusive result; 3=no thrombus. The presence of spontaneous echocontrast (SEC) was registered and flow velocity in the LA appendage (LAA-flow) was measured. All patients in whom CV was performed were followed up for 1 year or until relapse of AF. CV related adverse events were defined as any thromboembolic event within 1 week after CV.

Results

No serious adverse events occurred during TEE and contrast enhanced imaging. In group 1 atrial thrombi were diagnosed in 14 (15.6%) during native and in 10 (11.1%) patients during contrast enhanced imaging (p<0.001). Of the 10 patients with thrombi in the contrast TEE group, 7 revealed a decreased LAA-flow (≤0,3m/s) and 8 showed moderate or marked SEC. Uncertain results were significantly more common during native imaging than with contrast enhanced TEE (16 vs. 5 patients, p<0.01). Thrombi could definitely be excluded in 60 (66.7%) during conventional and in 75 patients (83.3%) during contrast enhanced TEE (p<0.01). CV was performed subsequently after exclusion of thrombi and at the discretion of the investigator. In group 1, 74 patients (82.2%) were cardioverted and no patient suffered a CV related complication (p=0.084). In group 2, 76 patients (84.4%) underwent CV, of whom 3 suffered a thromboembolic complication after CV (2 strokes, 1 peripheral embolism).

Conclusion

In patients with AF planned for CV contrast enhancement renders TEE images more interpretable, facilitates the exclusion of atrial thrombi and may reduce the rate of embolic adverse events.     

Cardiac conduction abnormalities and Stokes-Adams attacks in myotonic dystrophy.

Myotonic dystrophy is a well known cause of cardiomyopathy. While various cardiac conduction abnormalities have been described in patients with myotonic dystrophy, so far only sporadic cases of Stokes-Adams attacks have been reported. Of 27 patients with this disease various conduction disturbances were detected in 17 (63%), 5 of whom presented with Stokes-Adams attacks and were found to have intracardiac conduction defects. The prognosis in four of the five patients was greatly improved with permanent pacemaker implantation.     

Impact of Triple Therapy in Elderly Patients with Atrial Fibrillation Undergoing Percutaneous Coronary Intervention

Background and Purpose

Selecting an ideal antithrombotic therapy for elderly patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI) can be challenging since they have a higher thromboembolic and bleeding risk than younger patients. The current study aimed to assess the efficacy and safety of triple therapy (TT: oral anticoagulation plus dual antiplatelet therapy: aspirin plus clopidogrel) in patients ≥75 years of age with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI).

Methods

A prospective multicenter study was conducted from 2003 to 2012 at 6 Spanish teaching hospitals. A cohort study of consecutive patients with AF undergoing PCI and treated with TT or dual antiplatelet therapy (DAPT) was analyzed. All outcomes were evaluated at 1-year of follow-up.

Results

Five hundred and eighty-five patients, 289 (49%) of whom were ≥75 years of age (79.6±3.4 years; 33% women) were identified. TT was prescribed in 55.9% of patients at discharge who had a higher thromboembolic risk (CHA₂DS₂VASc score: 4.23±1.51 vs 3.76±1.40, p = 0.007 and a higher bleeding risk (HAS-BLED ≥3: 88.6% vs 79.2%, p = 0.02) than those on DAPT. Therefore, patients on TT had a lower rate of thromboembolism than those on DAPT (0.6% vs 6.9%, p = 0.004; HR 0.08, 95% CI: 0.01–0.70, p = 0.004). Major bleeding events occurred more frequently in patients on TT than in those on DAPT (11.7% vs 2.4%, p = 0.002; HR 5.2, 95% CI: 1.53–17.57, p = 0.008). The overall mortality rate was similar in both treatment groups (11.9% vs 13.9%, p = 0.38); however, after adjustment for confounding variables, TT was associated with a reduced mortality rate (HR 0.33, 95% CI: 0.12–0.86, p = 0.02).

Conclusions

In elderly patients with AF undergoing PCI, the use of TT compared to DAPT was associated with reduced thromboembolism and mortality rates, although a higher rate of major bleeding.     

起搏器术后新发房性心律失常的影响因素分析

目的:探讨起搏器术后新发房性心律失常的发生情况及其相关影响因素。方法:选择2006年1月至2007年12月于沈阳军区总医院首次植入永久起搏器的107例患者,男性50例,平均年龄65.0±11.9岁,术前通过追问病史及相关检查均排除房性心律失常(房颤、房扑、房速),术后平均随访3.9年,观察新发房性心律失常情况。按术后是否出现房性心律失常,将患者分为新发房性心律失常组和无房性心律失常组,比较两组患者术前和术后心脏超声结果的变化、心室起搏比例、起搏部位及起搏模式,并通过logistic回归分析起搏器术后发生房性心律失常的影响因素。结果:新发房性心律失常组26例(24.3%),其中房颤17例(15.9%),房扑2例(1.9%),房速7例(6.5%);无房性心律失常组81例。与无房性心律失常组比较,新发房性心律失常组左房内径明显增加(P=0.040)、二尖瓣返流程度较重(P=0.032)及左室射血分数明显下降(P=0.001),心室起搏百分比(VP%)显著升高(P=0.017)。心尖部起搏患者房性心律失常的发生率明显高于间隔部起搏(33.3%vs 16.9%,P<0.05),双腔起搏组患者房性心律失常发生率明显低于单腔起搏器组(18.7%vs 37.5%,P<0.05)。Logistic回归分析显示术后新发房性心律失常的发生与高比例的心室起搏(P=0.006)、VVI(R)起搏模式(P=0.014)及右心室起搏电极导线植于心尖部(P=0.024)显著相关。结论:起搏模式、心室起搏百分比、起搏部位是起搏器术后发生房性心律失常的影响因素。