A single-centre prospective evaluation of left bundle branch area pacemaker implantation characteristics.

BACKGROUND: Left bundle branch area pacing (LBBAP) has recently been introduced as a physiological pacing technique with synchronous left ventricular activation. It was our aim to evaluate the feasibility and learning curve of the technique, as well as the electrical characteristics of LBBAP. METHODS AND RESULTS: LBBAP was attempted in 80 consecutive patients and electrocardiographic characteristics were evaluated during intrinsic rhythm, right ventricular septum pacing (RVSP) and LBBAP. Permanent lead implantation was successful in 77 of 80 patients (96%). LBBAP lead implantation time and fluoroscopy time shortened significantly from 33 ± 16 and 21 ± 13 min to 17 ± 5 and 12 ± 7 min, respectively, from the first 20 to the last 20 patients. Left bundle branch (LBB) capture was achieved in 54 of 80 patients (68%). In 36 of 45 patients (80%) with intact atrioventricular conduction and narrow QRS, an LBB potential (LBBpot) was present with an LBBpot to onset of QRS interval of 22 ± 6 ms. QRS duration increased significantly more during RVSP (141 ± 20 ms) than during LBBAP (125 ± 19 ms), compared to 130 ± 30 ms without pacing. An even clearer difference was observed for QRS area, which increased significantly more during RVSP (from 32 ± 16 µVs to 73 ± 20 µVs) than during LBBAP (41 ± 15 µVs). QRS area was significantly smaller in patients with LBB capture compared to patients without LBB capture (43 ± 18 µVs vs 54 ± 21 µVs, respectively). In patients with LBB capture (n = 54), the interval from the pacing stimulus to R­wave peak time in lead V6 was significantly shorter than in patients without LBB capture (75 ± 14 vs 88 ± 9 ms, respectively). CONCLUSION: LBBAP is a safe and feasible technique, with a clear learning curve that seems to flatten after 40-60 implantations. LBB capture is achieved in two-thirds of patients. Compared to RVSP, LBBAP largely maintains ventricular electrical synchrony at a level close to intrinsic (narrow QRS) rhythm.

Clinical determinants of early spontaneous conversion to sinus rhythm in patients with atrial fibrillation.

BACKGROUND: The current standard of care for acute atrial fibrillation (AF) focuses primarily on immediate restoration of sinus rhythm by cardioversion, although AF often terminates spontaneously. OBJECTIVE: To identify determinants of early spontaneous conversion (SCV) in patients presenting at the emergency department (ED) because of AF. METHODS: An observational study was performed of patients who visited the ED with documented AF between July 2014 and December 2016. The clinical characteristics and demographics of patients with and without SCV were compared. RESULTS: We enrolled 943 patients (age 69 ± 12 years, 47% female). SCV occurred within 3 h of presentation in 158 patients (16.8%). Logistic regression analysis showed that duration of AF <24 h [odds ratio (OR) 7.7, 95% confidence interval (CI) 3.5-17.2, p < 0.001], left atrial volume index <42 ml/m2 (OR 1.8, 95% CI 1.2-2.8, p = 0.010), symptoms of near-collapse at presentation (OR 2.4, 95% CI 1.2-5.1, p = 0.018), a lower body mass index (BMI) (OR 0.9, 95% CI 0.91-0.99, p = 0.028), a longer QTc time during AF (OR 1.01, 95% CI 1.0-1.02, p = 0.002) and first-detected AF (OR 2.5, 95% CI 1.6-3.9, p < 0.001) were independent determinants of early SCV. CONCLUSION: Early spontaneous conversion of acute AF occurs in almost one-sixth of admitted patients during a short initial observation in the ED. Spontaneous conversion is most likely to occur in patients with first-onset, short-duration AF episodes, lower BMI, and normal left atrial size.

Concealed Coronary Atherosclerosis In Idiopathic Paroxysmal Atrial Fibrillation is Associated with Imminent Cardiovascular Diseases.

BACKGROUND: Previous research showed a significant difference in the presence of subclinical coronary artery disease (CAD) on cardiac CT angiography (CTA) between patients with idiopathic paroxysmal atrial fibrillation (iAF) versus a matched sinus rhythm population (iSR). Here we present 5-year follow-up data and the consequences of subclinical CAD on baseline CTA on the development of cardiovascular disease in iAF. METHODS: In 99 iAF patients (who underwent CTA as part of work-up for pulmonary vein isolation) and 221 matched iSR controls (who underwent CTA for CAD assessment), the incidence of hypertension, diabetes and major cardiovascular events (MACCE) during follow-up was obtained. Multivariable Cox regression analysis was used to reveal predictors of incident cardiovascular disease in the iAF group. RESULTS: During a follow-up of 68±11 months, over one third of patients developed cardiovascular disease, with no difference between iAF and iSR (log-rank p=0.56), and comparable low rates of MACCE (4.0% vs 5.0%,p=0.71). Within the iAF group, age (HR1.12(1.03-1.20);p=0.006), left atrial diameter (HR1.16(1.03-1.31);p=0.01), Segment Involvement Score (total number of coronary segments with atherosclerotic plaque; HR1.43(1.09-1.89);p=0.01) and the number of calcified plaques on CTA (HR0.53(0.30-0.92);p=0.01) were independent predictors of incident cardiovascular disease. CONCLUSIONS: Subclinical coronary disease on CTA may be useful to identify the subset of patients with iAF that harbour concealed cardiovascular risk factors and need intensive clinical follow-up to ensure timely initiation of appropriate therapy once CV disease develops, including anticoagulation and vascular prophylactic therapy.

Idiopathic atrial fibrillation patients rapidly outgrow their low thromboembolic risk: a 10-year follow-up study.

BACKGROUND: Healthy atrial fibrillation (AF) patients will eventually outgrow their low thromboembolic risk. The purpose of this study is to compare the development of cardiovascular disease in healthy AF patients as compared to healthy sinus rhythm patients and to assess appropriate anticoagulation treatment. METHODS: Forty-one idiopathic paroxysmal AF patients (56 ± 10 years, 66% male) were compared with 45 healthy sinus rhythm patients. 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. RESULTS: Baseline characteristics and echocardiographic parameters were the same in both groups. During 10.7 ± 1.6 years, cardiovascular disease and all-cause death developed significantly more often in AF patients as compared to controls (63% vs 31%, log rank p < 0.001). Even after the initial 5 years of follow-up, survival curves show divergent patterns (log rank p = 0.006). Mean duration to reach a CHA2DS2-VASc score > 1 among AF patients was 5.1 ± 3.0 years. Five of 24 (21%) patients with CHA2DS2-VASc > 1 did not receive oral anticoagulation therapy at follow-up. Mean duration of over- or undertreatment with oral anticoagulation in patients with CHA2DS2-VASc > 1 was 5 ± 3.0 years. CONCLUSION: The majority of recently diagnosed healthy AF patients develop cardiovascular diseases with a consequent change in thromboembolic risk profile within a short time frame. A comprehensive follow-up of this patient category is necessary to avoid over- and undertreatment with anticoagulants.

Presence and extent of cardiac computed tomography angiography defined coronary artery disease in patients presenting with syncope.

BACKGROUND: In syncope patients, presence of coronary artery disease (CAD) is associated with poor prognosis. However, data concerning CAD prevalence in syncope patients without known cardiovascular disease are lacking. Therefore, the aim of this study was to investigate presence and extent of CAD in syncope patients. METHODS: We included 142 consecutive patients presenting with syncope at the outpatient cardiology clinic who underwent coronary computed tomography (CT) angiography. Syncope type was ascertained by two reviewers, blinded for coronary CT angiography results. Of the patients, 49 had cardiac syncope (arrhythmia or structural cardiopulmonary disease) and 93 had non-cardiac syncope (reflex [neurally-mediated], orthostatic or of unknown cause). Cardiac syncope patients were compared with matched stable chest pain patients regarding age, gender, smoking status, diabetes mellitus type 2 and systolic blood pressure. RESULTS: Distribution of CAD presence and extent in cardiac and non-cardiac syncope patients was as follows: 72% versus 48% any CAD; 31% versus 26% mild, 8% versus 14% moderate and 33% versus 7% severe CAD. Compared with non-cardiac syncope, patients with cardiac syncope had a significantly higher CAD presence and extent (p = 0.001). Coronary calcium score, segment involvement and stenosis score were also higher in cardiac syncope patients (p-values ≤0.004). Compared to the chest pain control group, patients with cardiac syncope showed a higher, however, non-significant, prevalence of any CAD (72% versus 63%) and severe CAD (33% versus 19%). CONCLUSION: Patients with cardiac syncope show a high presence and extent of CAD in contrast to non-cardiac syncope patients. These results suggest that CAD may play an important role in the occurrence of cardiac syncope.

Pathophysiology of idiopathic atrial fibrillation - prognostic and treatment implications.

The term idiopathic or lone atrial fibrillation (AF) is commonly used in the young and apparently healthy individual who suffers from AF. Although there is conflicting evidence concerning prognosis, these patients are at risk to develop (vascular) comorbidities in the years following AF onset. It is conceivable that early stages of vascular disease, undetectable by the routine diagnostics, may contribute to the pathophysiology of "apparently" idiopathic AF. At present, more advanced diagnostics have become available that can be deployed at low threshold in order to detect early stage or yet subclinical cardiovascular disease. In this respect one could raise the question whether idiopathic AF exists at all or that the arrhythmia acts as a harbinger of as yet undetected underlying vascular disease in this specific population. Assuming that idiopathic AF is the final arrhythmic expression of underlying genetic mutations and/or vascular diseases, high priority should be given to trace identifiable predisposing factors or the presence of early stages of underlying disease in order to treat these, or prevent their complications. A more comprehensive quest for potential hidden causes of idiopathic AF creates new therapeutic dilemmas, but also encourages further research regarding pathophysiology and new early treatment opportunities in patients with atrial fibrillation in general. The present review provides more insight regarding diverse pathophysiological mechanisms in the fundamental basis for idiopathic AF, outlines prognostic and treatment implications, and questions the robustness of its definition.

Lone or idiopathic atrial fibrillation, messenger of misery in sight.

This editorial refers to 'Gender-related differences in risk of cardiovascular morbidity and all-cause mortality in patients hospitalized with incident atrial fibrillation without concomitant diseases: a nationwide cohort study of 9519 patients' by T. Andersson et al. In order to adequately describe root causes and adverse consequences of apparently idiopathic AF, the requested study population has to be large and be followed for a very long time. Andersson et al. adequately deployed the excellent national Swedish health registries in order to cover the hiatus of aforementioned studies in the current idiopathic AF literature. Considering the notion that patients with idiopathic or lone AF have comparable prospects as AF patients overall but are only caught early in their 'arrhythmia and vascular career', the study by Andersson et al. should trigger physicians to give high priority to exposing predisposing factors or early stages of underlying cardiovascular disease in such a way that preventative measures can be accurately deployed in these patients.

Low efficacy of cardioversion of persistent atrial fibrillation with the implantable cardioverter-defibrillator.

AIMS: Atrial fibrillation (AF) and heart failure are conditions that often coexist. Consequently, many patients with an implantable cardioverter-defibrillator (ICD) present with AF. We evaluated the effectiveness of internal cardioversion of AF in patients with an ICD. METHODS: Retrospectively, we included 27 consecutive ICD patients with persistent AF who underwent internal cardioversion using the ICD. When ICD cardioversion failed, external cardioversion was performed. RESULTS: Patients were predominantly male (89 %) with a mean (SD) age of 65 ± 9 years and left ventricular ejection fraction of 36 ± 17 %. Only nine (33 %) patients had successful internal cardioversion after one, two or three shocks. The remaining 18 patients underwent external cardioversion after they failed internal cardioversion, which resulted in sinus rhythm in all. A smaller left atrial volume (99 ± 36 ml vs. 146 ± 44 ml; p = 0.019), a longer right atrial cycle length (227 (186-255) vs. 169 (152-183) ms, p = 0.030), a shorter total AF history (2 (0-17) months vs. 40 (5-75) months, p = 0.025) and dual-coil ICD shock (75 % vs. 26 %, p = 0.093) were associated with successful ICD cardioversion. CONCLUSION: Internal cardioversion of AF in ICD patients has a low success rate but may be attempted in those with small atria, a long right atrial fibrillatory cycle length and a short total AF history, especially when a dual-coil ICD is present. Otherwise, it seems reasonable to prefer external over internal cardioversion when it comes to termination of persistent AF.

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.

Semi-final masked hypertension.

Masked hypertension is normal blood pressures (BP) in a clinical setting and high BP during ambulatory monitoring. Although these patients are at higher cardiovascular risk, there is still no clear consensus definition of masked hypertension.

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 alpha 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.