Bob Weijs

Atrial Tissue Doppler Imaging For Prediction Of New-Onset Atrial Fibrillation

Background: The total atrial conduction time (TACT) is an independent predictor of atrial fibrillation (AF). A new transthoracic echocardiographic tool to determine TACT by tissue Doppler imaging (PA-TDI (the time from the initiation of the P wave on the ECG (lead II) to the A′ wave on the lateral left atrial tissue Doppler tracing)) has been developed recently. Objective: To test the hypothesis that measurement of PA-TDI enables prediction of new-onset AF. Methods: 249 Patients without a history of AF were studied. All patients underwent an echocardiogram and the PA-TDI interval was measured. Patient characteristics and rhythm at follow-up were recorded. Results: During a mean (SD) follow-up of 680 (290) days, 15 patients (6%) developed new-onset AF. These patients had a longer PA-TDI interval than patients who remained in sinus rhythm (172 (25) ms vs 150 (20) ms, p = 0.001). Furthermore, the patients developing AF were older, more often had a history of heart failure or chronic obstructive pulmonary disease, more often used α blockers, had enlarged left atria and more frequently mitral incompetence on the echocardiogram. After adjusting for potential confounders, Cox regression showed that PA-TDI was independently associated with new-onset AF (OR = 1.375; 95% CI 1.037 to 1.823; p = 0.027). The 2-year incidence of AF was 33% in patients with a PA-TDI interval >190 ms versus 0% in patients with a PA-TDI interval <130 ms (p = 0.002). Conclusions: A prolonged PA-TDI interval may predict the development of new-onset AF. This measure may be used to identify patients at risk in future strategies to prevent the development or complications of AF.

Patients using vitamin K antagonists show increased levels of coronary calcification: an observational study in low-risk atrial fibrillation patients

AIMS Vitamin K antagonists (VKA) are currently the most frequently used drug to prevent ischaemic stroke in atrial fibrillation (AF) patients. However, VKA use has been associated with increased vascular calcification. The aim of this study was to investigate the contribution of VKA use to coronary artery calcification in low-risk AF patients. METHODS AND RESULTS A prospective coronary calcium scan was performed in 157 AF patients without significant cardiovascular disease (108 males; mean age 57 ± 9 years). A total of 71 (45%) patients were chronic VKA users. The duration of VKA treatment varied between 6 and 143 months (mean 46 months). No significant differences in clinical characteristics were found between patients on VKA treatment and non-anticoagulated patients. However, median coronary artery calcium scores differed significantly between patients without and patients with VKA treatment [0, inter-quartile range (IQR) 0-40, vs. 29, IQR 0-184; P = 0.001]. Mean coronary calcium scores increased with the duration of VKA use (no VKA: 53 ± 115, 6-60 months on VKA: 90 ± 167, and >60 months on VKA: 236 ± 278; P < 0.001). Multivariable logistic regression analysis revealed that age and VKA treatment were significantly related to increased coronary calcium score. CONCLUSION Patients using VKA show increased levels of coronary calcification. Age and VKA treatment were independently related to increased coronary calcium score.

Contemporary real life cardioversion of atrial fibrillation: Results from the multinational RHYTHM-AF study.

AIMS Electrical and pharmacological cardioversion (ECV, PCV) are important treatment options for symptomatic patients with recent onset atrial fibrillation (AF). RHYTHM-AF is an international registry of present-day cardioversion providing information that is not currently available on country differences and acute and long-term arrhythmia outcomes of ECV and PCV. METHODS AND RESULTS 3940 patients were enrolled, of whom 75% underwent CV. All patients were followed for 2 months. There were large variations concerning mode of CV used, ECV being heterogeneous. A choice of PCV drug depended on the clinical patient profile. Sinus rhythm was restored in 89.7% of patients by ECV and in 69.1% after PCV. Among patients not undergoing CV during admission, 34% spontaneously converted to sinus rhythm within 24h. ECV was most successful in patients pretreated with antiarrhythmic drugs (mostly amiodarone). PCV was enhanced by class Ic antiarrhythmic drugs; conversion rate on amiodarone was similar to that seen with rate control drugs. Female patients and those with paroxysmal and first detected AF as well as those without previous ECV responded well to PCV. The median duration of hospital stay was 16.2 and 24.0 h for ECV and PCV patients, respectively. There were very few CV-related complications regardless of mode of CV. Chronic maintenance of sinus rhythm was enhanced in patients on chronic antiarrhythmic drugs, beta-blockers or inhibitors of the renin-angiotensin system. CONCLUSIONS Mode of CV varied significantly, but both PCV and ECV were safe and effective. Class Ic drugs were most effective conversion drugs, but amiodarone is used most frequently despite providing merely rate control rather than shorten time to conversion.

Patients originally diagnosed with idiopathic atrial fibrillation more often suffer from insidious coronary artery disease compared to healthy sinus rhythm controls

BACKGROUND Idiopathic atrial fibrillation (AF) refers to a clinically lacking cardiovascular or pulmonary disease generating the pathophysiologic substrate for the arrhythmia. However, because idiopathic AF is associated with an increased event rate, it could be a harbinger of as-yet undetected underlying heart disease. OBJECTIVE The purpose of this study was to determine the prevalence of coronary artery disease (CAD) in patients diagnosed with idiopathic paroxysmal AF. METHODS Of the 3243 patients who underwent cardiac computed tomographic angiography (CTA) in our center between January 2008 and March 2011, we identified a total of 115 consecutive idiopathic paroxysmal AF patients who underwent CTA before electrophysiologic ablation. Patients were compared with 275 age-, sex-, and PROCAM risk score-matched healthy controls in permanent sinus rhythm. All patients were free of hypertension, diabetes, congestive heart failure, previous known coronary artery and peripheral vascular disease, previous stroke, thyroid, pulmonary, and renal disease, and structural abnormalities on echocardiography. RESULTS Controls more often showed a family history of CAD (38% vs 15%, P <.001), had a higher prevalence of smoking (25% vs 14%, P = .021), higher fasting blood glucose levels (5.5 ± 0.7 mmol/L vs 5.4 ± 0.6 mmol/L, P = .025), and smaller atrial diameters (37 ± 4 mm vs 40 ± 5 mm, P <.001) compared to AF patients. Notwithstanding the above, idiopathic AF patients significantly more often suffered from subclinical CAD compared to controls (49% vs 34%, P = .008). Multivariable regression analysis revealed that beside (as expected) age and gender, a history of AF and left atrial diameter were significant predictors of underlying CAD. CONCLUSION Half of patients originally diagnosed with idiopathic paroxysmal AF show concealed underlying CAD. The detection and treatment of CAD at an early stage could improve the prognosis of these patients.

The occurrence of cardiovascular disease during 5-year follow-up in patients with idiopathic atrial fibrillation

AIMS Idiopathic atrial fibrillation (AF) may be an expression of as yet undetected underlying heart disease. We found it useful for clinical practice to study the long-term development of cardiovascular disease (CVD) in patients diagnosed with idiopathic AF. METHODS AND RESULTS Forty-one consecutive idiopathic AF patients (56 ± 10 years, 66% male) were compared with 45 healthy control patients in permanent sinus rhythm. Patients were free of hypertension, antihypertensive and antiarrhythmic drugs, diabetes, congestive heart failure, coronary artery or peripheral vascular disease, previous stroke, thyroid, pulmonary and renal disease, and structural abnormalities on echocardiography. Baseline characteristics and echocardiographic parameters were equal in AF cases and controls. During a mean follow-up of 66 ± 11 months, CVD occurred significantly more often in idiopathic AF patients compared with controls (49 vs. 20%, P= 0.006). Patients with idiopathic AF were significantly younger at the time of their first CV event compared with controls (59 ± 9 vs. 64 ± 5 years, P= 0.027), and had more severe disease. Multivariable Cox regression analysis revealed that age, a history of AF, and echocardiographic left ventricular wall width were significant predictors of CVD development. CONCLUSION Patients originally diagnosed with idiopathic AF develop CVD more often, at younger age, and with a more severe disease profile compared with healthy sinus rhythm control patients. The detection and treatment of CVD in an early stage could improve the prognosis of these patients. At present it seems prudent to regularly check idiopathic AF patients for the insidious development of CVD.

Idiopathic atrial fibrillation revisited in a large longitudinal clinical cohort.

AIMS An age of 60 years is often used as cut-off for the diagnosis of idiopathic atrial fibrillation (AF). We investigated the importance of age and atrial size in patients with idiopathic AF and AF patients with isolated hypertension. METHODS AND RESULTS Out of 3978 AF patients in the Euro Heart Survey on AF with known follow-up, 119 (3%) patients had idiopathic AF. We disregarded age and atrial size when selecting idiopathic AF patients since the atria may enlarge by AF itself. For comparison, we selected 152 patients with isolated hypertension from the database. A total of 57 (48%) of the patients were older than 60 years. Persistent or permanent AF was more prevalent in the older idiopathic AF patients (34% in the age <60 vs. 66% in the age >60 years group, P= 0.002) but mean duration of known AF did not differ between these groups [310 days (inter-quartile range, IQR) 60-1827) vs. 430 days (IQR 88-1669), P= 0.824]. Left atrial size did not differ significantly in relation to age (1.50 ± 0.29 mm/kg/m² in the age <60 vs. 1.56 ± 0.31 mm/kg/m² in the age >60 years group, P= 0.742). Only two paroxysmal AF patients progressed to permanent AF. No cardiovascular events occurred during the 1-year follow-up. In contrast, strokes occurred in five patients (6%) with isolated hypertension despite similar clinical profile and comparable atrial size as idiopathic AF patients. CONCLUSION Idiopathic AF may present at advanced age and is even then not associated with significant atrial enlargement, AF progression, or an adverse short-term prognosis. In contrast, elevated blood pressure even when found in the absence of significant atrial remodelling, seems of prognostic importance.

Clinical and echocardiographic correlates of intra-atrial conduction delay

AIMS The total atrial conduction time (TACT) is an important electrophysiological parameter. We developed a new transthoracic echocardiographic tool (PA-TDI). The PA-TDI interval is a reflection of the TACT. In the present study, we evaluated the clinical and echocardiographic correlates of intra-atrial conduction delay. METHODS AND RESULTS We studied 427 patients without class I anti-arrhythmic agents or amiodarone. All patients underwent an echocardiogram and the PA-TDI interval was measured. Patient characteristics were recorded. The mean PA-TDI was 157 ± 22 ms. Multivariate linear regression analysis revealed that atrial fibrillation (AF) in history (B = 9.7; 95%CI 5.7-13.8; P < 0.001), hypertension (B = 5.5; 95%CI 1.4-9.8; P = 0.01), clinically relevant valve disease (B = 5.7; 95%CI 0.5-10.8; P = 0.03), age (B = 5; 95%CI 3.3-6.6; P < 0.001), and body mass index (BMI; B = 2.6; 95%CI 0.3-4.9; P = 0.026) were independently associated with the PA-TDI interval. On the echocardiogram: the aortic diameter (B = 0.7; 95%CI 0.2-1.2; P = 0.009), left atrial dimension (B = 0.9; 95%CI 0.5-1.3; P < 0.001), mitral valve E-wave deceleration time (B = 0.1; 95%CI 0.1-0.1; P < 0.001), aortic incompetence (B = 13; 95%CI 3.3-22.6; P = 0.008), and mitral incompetence (B = 11; 95%CI 3.6-17.5; P < 0.003) were independently associated with the PA-TDI interval. CONCLUSION This study is the largest to investigate the relation between the atrial conduction time, underlying heart diseases, and echocardiographic parameters. We found that the PA-TDI was independently prolonged in patients with a history of AF, hypertension, valve disease, higher age, and a higher BMI. Signs of diastolic dysfunction, valve incompetence, and enlarged atrium or aortic root on the echocardiogram were associated with a prolonged PA-TDI. This suggests that early and aggressive treatment of hypertension, diastolic dysfunction, and obesity could prevent intra-atrial conduction delay.

The presence of an atrial electromechanical delay in idiopathic atrial fibrillation as determined by tissue Doppler imaging

Atrial fibrillation (AF) derives from a complex continuum of predisposing factors. However, the true ‘scene of calamity’ is the atrium. Increased left atrial (LA) size is associated with increased risk of AF onset and recurrence, other cardiovascular disease and mortality [1, 2]. Both atrial conduction slowing and atrial dilatation will favour AF as it results in increased total atrial conduction time, which is the time elapsed between the initiation of atrial depolarisation and the last depolarisation of the same activation front [3]. A prolonged total atrial conduction time may reflect the electro-anatomical substrate for AF since it is associated with underlying cardiovascular disease and age [4]. It can be easily and non-invasively determined by means of transthoracic echocardiography assessing the electromechanical PA interval with tissue Doppler imaging (PA-TDI) [5]. Idiopathic AF refers to AF in the absence of a cardiovascular or pulmonary disease generating the pathophysiological substrate for the arrhythmia. Herein, we study the electrophysiologic properties of the atria in patients with idiopathic AF using tissue Doppler imaging. We prospectively studied 41 consecutive idiopathic AF patients and 45 healthy sinus rhythm control patients who were referred to the outpatient clinic for a standard transthoracic echocardiographic examination. Informed consent of all patients was obtained and the authors of this manuscript have certified that they comply with the Principles of Ethical Publishing in the International Journal of Cardiology [6]. Idiopathic AF and healthy sinus rhythm was strictly defined as the absence of any cardiovascular disease including hypertension (no

Clinical correlates of echocardiographic tissue velocity imaging abnormalities of the left atrial wall during atrial fibrillation.

AIMS In patients with atrial fibrillation (AF), echocardiographic tissue velocity imaging (TVI) enables assessment of electrical and structural remodelling by measuring, respectively, the AF cycle length (AFCL-TVI) and the atrial fibrillatory wall motion velocity (AFV-TVI). We investigated the clinical and echocardiographic correlates of atrial remodelling assessed by TVI. METHODS AND RESULTS We studied 215 patients presenting with AF. In all patients, we measured the AFCL-TVI and the AFV-TVI in the left atrium. Standard baseline characteristics were recorded. We divided patients by median value of AFV-TVI and AFCL-TVI to evaluate the determinants of atrial remodelling. A low AFV-TVI was related with a longer median duration of the current AF episode, a higher prevalence of significant mitral regurgitation and a thicker left ventricle (LV). Multivariate analysis revealed that a low AFV-TVI was independently associated with a longer median duration of the current AF episode [OR 0.09 (95% CI 0.03-0.027); P < 0.001]. Univariately, a short AFCL-TVI was associated with a long median duration of the current AF episode, the use of anti-arrhythmic drugs, a lower LV ejection fraction (LVEF) and a smaller left atrial volume index (LAVI). Multivariate analysis revealed that LVEF [OR 1.48 (95% CI 1.09-2.01); P = 0.013] and LAVI [OR 1.37 (95% CI 1.08-1.74); P = 0.010] were independently associated with AFCL-TVI. CONCLUSION This study investigated the clinical and echocardiographic correlates of atrial remodelling assessed by TVI. The AFV-TVI is reduced in patients with a long AF duration and who have mitral regurgitation. In addition, the AFCL is long if LAVI is high and LVEF preserved. Tissue velocity imaging parameters measured during AF may be helpful to characterize the degree of atrial remodelling and optimize treatment.

Tissue velocity imaging of the left atrium predicts response to flecainide in patients with acute atrial fibrillation

BACKGROUND Acute atrial fibrillation (AF) is often treated with the administration of intravenous flecainide; however, this treatment may not always be successful and is potentially hazardous. Previous studies suggest that electro-echocardiographic tissue velocity imaging (TVI) of the atrial wall may reflect atrial remodeling. OBJECTIVE To study whether atrial TVI can be used to identify nonresponders of flecainide administered intravenously in patients with acute AF. METHODS We used atrial TVI to measure atrial fibrillatory cycle length determined by using tissue velocity imaging (AFCL-TVI) and atrial fibrillatory wall motion velocity determined by using tissue velocity imaging (AFV-TVI) in the left atrium in 52 (55%) patients presenting with acute AF in the emergency department. These 2 parameters reflect electrical and structural remodeling, respectively. Standard baseline characteristics were recorded. RESULTS Patients were predominantly men (76%) and 64 ± 11 years old. Thirty-six (69%) patients had successful cardioversion after flecainide infusion. There were no significant differences in baseline characteristics between responders and nonresponders. Patients with a successful cardioversion had a longer mean AFCL-TVI and higher median (interquartile range) AFV-TVI compared with patients with failed cardioversion: 172 ± 29 ms vs 137 ± 35 ms (P < .001) and 4.2 (3.3-6.2) cm/s vs 2.3 (1.9-3.5) cm/s (P = .001). CONCLUSIONS Electro-echocardiographic atrial TVI measurement is a promising noninvasive tool for predicting outcome of pharmacological cardioversion. A short AFCL-TVI and a low AFV-TVI are related to failure of cardioversion of AF using flecainide.