Troponin T and N-Terminal Pro-Brain Natriuretic Peptide Are Associated with Long-Term All-Cause Mortality in Patients with Post-Sternotomy Mediastinitis following Coronary Artery Bypass Grafting: A 15-Year Follow-Up Study.

BACKGROUND: Deep sternal wound/mediastinitis is a rare but feared complication in coronary artery bypass grafting (CABG) patients and seems to increase the risk of cardiac death, and is also associated with the risk of early internal mammary artery (IMA) graft obstruction. The pathological mechanism explaining the link between mediastinitis and IMA graft obstruction and the impact on mortality is complex, multifactorial, and not fully investigated. OBJECTIVES: Mediastinitis has been associated with increased concentrations of N-terminal pro-brain natriuretic peptide (NT-proBNP) and troponin T (TnT) at mid-term follow-up, representing persistent low-grade myocardial injury and impaired cardiac function. However, whether mediastinitis is associated with all-cause mortality, or whether the association is driven by these cardiac-specific biomarkers (NT-proBNP and TnT), is not investigated. METHODS: The present study provides the longest and most complete follow-up data in 82 patients undergoing CABG, including 41 with post-sternotomy mediastinitis. RESULTS: The annualized incidence rate of mediastinitis was 0.14%/year and remained stable at 0.14% throughout the study period. During a mean follow-up of 12.7 ± 3.5 years, a total of 42 deaths occurred (27 [65.9%] in mediastinitis and 15 [36.6%] in non-mediastinitis group, p = 0.008). No association was found between IMA or saphenous vein graft obstruction with all-cause mortality. Mediastinitis was associated with a 1.9-fold increased risk of all-cause mortality. However, in the multivariable-adjusted models, age and higher TnT and NT-proBNP levels, but not mediastinitis per se were associated with all-cause mortality. CONCLUSIONS: Mediastinitis after CABG surgery was associated with a poor prognosis during a 15-year follow-up, showing a nearly two-fold higher frequency of all-cause mortality compared with non-mediastinitis group, with the differences in mortality rate occurring primarily after 10 years. The association between mediastinitis and all-cause mortality was modulated by subclinical myocardial damage and stretch, reflected by elevated TnT and NT-proBNP, measured at 2.7-year follow-up, underscoring that these could represent prognostic markers in CABG patients.

Natural Course of Electrocardiogram Changes and the Value of Multimodality Imaging in Acute Pericarditis.

BACKGROUND: ECG is the initial diagnostic tool that in combination with typical symptoms often raises the suspicion of pericarditis. Echocardiography remains the first-line imaging modality for assessment of pericardial diseases, particularly effusion/tamponade, constrictive physiology, and assessment of regional wall motion abnormalities as differential diagnoses. However, cardiac CT and cardiac magnetic resonance may be necessary in complicated cases and to identify pericardial inflammation in specific settings (atypical presentation, new onset constriction), as well as myocardial involvement and monitoring the disease activity. SUMMARY: In acute pericarditis, the most commonly used ECG criteria recommended by international guidelines are the widespread ST-segment elevation or PR depression. However, the classic ECG pattern of widespread ST-segment elevation or PR depression can be seen in less than 60% of patients. In addition, ECG changes are often temporally dynamic, evolve rapidly during the course of disease, and may be influenced by a number of factors such as disease severity, time (stage) of presentation, degree of myocardial involvement, and the treatment initiated. Overall, temporal dynamic changes on ECG during acute pericarditis or myopericarditis have received limited attention. Hence, the aim of this brief clinical review was to increase awareness about the various ECG changes observed during the course of acute pericarditis. KEY MESSAGES: ECG may be normal at presentation or for days after the index episode of chest pain, but serial ECGs can reveal specific patterns of temporally dynamic ST elevation in patients with pericarditis or myopericarditis, particularly during new episodes of chest pain.

Cryoballoon vs. radiofrequency catheter ablation: insights from NOrwegian randomized study of PERSistent Atrial Fibrillation (NO-PERSAF study).

AIMS: Pulmonary vein isolation (PVI) is still regarded as a cornerstone for treatment of persistent atrial fibrillation (AF). This study evaluated the effectiveness of PVI performed with cryoballoon ablation (CBA) in comparison with radiofrequency ablation (RFA) in patients with persistent AF. METHODS AND RESULTS: A total of 101 patients with symptomatic persistent AF were enrolled and randomized (1:1) to CBA or RFA groups and followed up for 12 months. The primary endpoint was any documented recurrent atrial tachyarrhythmia (ATA) lasting longer than 30 s following a 3-month blanking period. Secondary endpoints were procedure-related complications, procedure and ablation duration, and fluoroscopy time. The ATA-free survival curves were estimated by Kaplan-Meier method and analysed by the log-rank test. According to intention-to-treat analysis, freedom from ATA was achieved in 36 out of 52 patients in the CBA group and 30 out of 49 patients in the RFA group (69.2% vs. 61.2%, P = 0.393). No difference in AF recurrence was found between the two groups (27.5% in CBA vs. 38.0% in RFA, P = 0.258), and less atrial flutter recurrence was documented in the CBA group compared with the RFA group (3.9% vs. 18.0%, P = 0.020). The procedure and ablation duration were significantly shorter in the CBA group (160 ± 31 vs. 197 ± 38 min, P < 0.0001; 36.7 ± 9.5 vs. 55.3 ± 16.7 min, P < 0.0001). There was no difference regarding fluoroscopy time (21.5 ± 7.8 vs. 23.4 ± 11.2 min, P > 0.05). CONCLUSION: Compared with RFA, PVI performed by CBA led to shorter procedure and ablation duration, with less atrial flutter recurrence and similar freedom from ATA at 12-month follow-up.

Loss of life years due to unavailable helicopter emergency medical service: a single base study from a rural area of Norway.

Background: Despite the potential benefits of physician-staffed Helicopter Emergency Medical Service (HEMS), many dispatches to primary HEMS missions in Norway are cancelled before patient encounter. Information is sparse regarding the health consequences when medically indicated HEMS missions are cancelled and the patients are treated by a GP and ambulance staff only. We aimed to estimate the potential loss of life years for patients in these situations. Method: We included all HEMS requests in the period 2010-2013 from Sogn and Fjordane County that were medically indicated but subsequently cancelled. This provided a selection of patients, with the purpose of studying cancellations independently of the patient's medical status A multidisciplinary expert panel retrospectively assessed each patient's potential loss of life years due to the lack of helicopter transport and intervention by a HEMS physician. Results: The study included 184 patients from 176 missions. Because of unavailable HEMS, seven patients (4%) were anticipated to have lost a total of 18 life years. Three patients suffered from myocardial infarction, three from stroke and one from abdominal haemorrhage. The main contribution from HEMS care in these seven cases might have been rapid transport to definitive care. The probability of a patient losing life years when in need of HEMS evacuation was found to be 0.2%. Conclusion: During the four years period seven patients lost 18 life years. Lack of rapid transport seems to be the primary cause of lost life years in this specific geographical area. Key Points Knowledge about to what extent HEMS contributes to an increased survival and a better outcome for patients is limited. Compared to similar studies on life years gained the estimated loss of life years was minor when HEMS evacuation was unavailable in this rural area. The findings indicates that lack of rapid HEMS transport was the primary cause of the estimated loss of life years.

Incidence and clinical predictors of subsequent atrial fibrillation requiring additional ablation after cavotricuspid isthmus ablation for typical atrial flutter.

OBJECTIVES: We sought to investigate the incidence of atrial fibrillation after catheter ablation for typical atrial flutter and to determine the predictors for symptomatic atrial fibrillation that required a further additional dedicated ablation procedure. DESIGN: 127 patients underwent elective cavotricuspid isthmus ablation with the indication of symptomatic, typical atrial flutter. The occurrence of atrial flutter, atrial fibrillation, cerebrovascular events and the need for additional ablation procedures for symptomatic atrial fibrillation was assessed during long-term follow-up. RESULTS: The majority of patients (70%) manifested atrial fibrillation during a follow-up period of 68 ± 24 months, and a significant proportion (42%) underwent one or multiple atrial fibrillation ablation procedures after an average of 26 months from the index procedure. Recurrence of typical atrial flutter was rare. Ten patients (8%) suffered cerebrovascular events. Earlier documentation of atrial fibrillation (OR 3.53), previous use of flecainide (OR 3.33) and left atrial diameter (OR 2.96) independently predicted occurrence of atrial fibrillation during the follow-up. A combination of pre- and intra-procedural documentation of atrial fibrillation (OR 3.81) and previous use of flecainide (OR 2.43) independently predicted additional atrial fibrillation ablation. DISCUSSION: Atrial fibrillation occurred in the majority of patients after ablation for typical atrial flutter and 42% of them required an additional dedicated ablation procedure. Pre- and intraprocedural documentation of atrial fibrillation together with previous use of flecainide independently predicted atrial fibrillation occurrence and a need for additional ablation. Anticoagulation treatment should be continued in high-risk patients in spite of clinical disappearance of atrial flutter.

10-year follow-up after radiofrequency ablation of idiopathic ventricular arrhythmias from right ventricular outflow tract.

BACKGROUND: The aim of this study was to examine the effect of radiofrequency ablation (RFA) of ventricular arrhythmias from right ventricular outflow tract (RVOT) during long-term follow-up. METHODS: A follow-up analysis was conducted using an in-house questionnaire, as well as a qualitative assessment of the patients' medical records. The study population of 34 patients had a previous diagnosis of idiopathic VT or frequent PVCs from the RVOT, and received RFA treatment between 2002 and 2005. RESULTS: The main symptoms prior to RFA were palpitations (82.4%) and dizziness (76.5%). A reduction in symptoms following RFA was reported by 91.2% of patients (p < 0.001). Furthermore, there was a reduced use of antiarrhythmic medication after RFA (p < 0.001). General health perception classified on a scale of 1 (poor) to 4 (excellent), improved from median class 1 to 3 (p < 0.001) during long-term follow-up. The fitness to work increased from median class 3 to class 5 (1 = incapacitated, 5 = full time employment, p = 0.038), while the rate of patients in full time employment increased from 26.5% to 55.9% after RFA (p = 0.02). CONCLUSIONS: A reduction of symptoms and use of antiarrhythmic medication, as well as an improvement in the general health perception and fitness to work after RFA of idiopathic ventricular arrhythmias can be demonstrated at ten-year follow-up.

Effect of flecainide on the extension and localization of complex fractionated electrogram during atrial fibrillation.

AIMS: Complex fractionated electrogram (CFE) ablation in addition to pulmonary vein isolation is an accepted strategy for the treatment of non-paroxysmal atrial fibrillation (AF). We sought to determine the effect of flecainide on the distribution and extension of CFE areas. METHODS: Twenty-three non-paroxysmal AF patients were enrolled in this prospective study. A first CFE map was obtained under baseline conditions by sampling 5 s of continuous recording from the distal electrodes of the ablation catheter. Intravenous flecainide (1 mg/kg) was administered over 10 min and followed by 30-min observation time. A second CFE map was obtained with the same modalities. CFE-mean values, CFE areas, and atrial electrogram amplitude were retrieved from the electro-anatomical mapping system (Ensite NavX). RESULTS: After flecainide administration, CFE-mean values increased (111.5 ± 55.3 vs. 132.3 ± 65.0 ms, p < 0.001) with a decrease of CFE area (32.9%) in all patients. Atrial electrogram amplitude decreased significantly (0.30 ± 0.31 vs. 0.25 ± 0.20 mV, p < 0.001). We observed 80.9% preservation of CFE areas. A CFE mean of 78 ms was the best cutoff for predicting stable CFE areas. CONCLUSIONS: Flecainide reduces the extension of CFE areas while preserving their spatial localization. A CFE-mean value <80 ms may be crucial to define and locate stable CFE areas.

"Ion-Flux": The natural course of ECG changes in severe hypokalemia.

Whereas the electrocardiogram (ECG) changes in hypokalemia are well known, they often receive less attention than the more striking features of hyperkalemia. Furthermore, there is a need for further discussion as to the subtleties of ECG changes that can aid in the differential diagnoses. This case study presents the ECG changes of a patient with severe hypokalemia due to diarrhea. It highlights how bifid T-waves in hypokalemia can be distinguished from other conditions such as coronary artery disease or pericarditis. Furthermore, it also shows the gradual reversal of ECG changes in the same patient when potassium is normalized.

Ablation effect indicated by impedance fall is correlated with contact force level during ablation for atrial fibrillation.

INTRODUCTION: Previous studies have validated the use of impedance fall as a measure of the effects of ablation. We investigated whether catheter-to-tissue contact force correlated with impedance fall during atrial fibrillation ablation. METHODS AND RESULTS: A total of 394 ablation points from 35 patients who underwent atrial fibrillation ablation were selected and analyzed in terms of the presence of stable catheter contact in non-ablated areas in the left atrium. A fixed power output (30 W) was applied for 60 seconds. Contact force, impedance fall, and force-direction angle were retrieved and exported for off-line analysis. Qualified points were divided into 5 groups according to the level of contact force (1-5 g, 6-10 g, 11-15 g, 16-20 g, and >20 g). An acute impedance fall was observed in the first 10 seconds followed by a plateau in group I and by a further fall in the other groups. Group V showed a rise in impedance during the last 20 seconds of ablation. Levels of impedance fall at each time point were significantly different among all the groups (P<0.001) except between groups III and IV. There was a significant correlation between contact force and maximum impedance fall (rho = 0.54, P<0.01). Lesions with a force-direction angle of 0-30° had significantly lower contact force and maximum impedance fall than those with angles of 30-60° and 60-135° (P<0.01). CONCLUSIONS: Under stable catheter conditions, contact force correlates with impedance fall during 60 seconds of ablation. Contact force exceeding 5 g produces greater impedance fall, which probably indicates adequate lesion formation. A contact force greater than 20 g may lead to late tissue overheating.

A BRASH Diagnosis With a Timely Intervention.

The BRASH (bradycardia, renal failure, atrioventricular block, shock, and hyperkalaemia) syndrome is a recently recognized condition which may lead to life-threatening complications if not correctly identified and treated early. We report here the case of a 74-year-old woman with type 2 diabetes, hypertension and atrial flutter who presented to the emergency department with 2-day history of dizziness, presyncope, and bradycardia, and a junctional rhythm at 61 beat per minute on initial ECG. She was on apixaban, digoxin, prazosin, and telmisartan. Serum biochemistry revealed severe hyperkalaemia with a potassium 8.4 mmol/L, creatinine 161 mmol/L, glucose 15.3 mmol/L and an upper normal digoxin level of 1.2 mmol/L (ref. 0.6-1.2). Arterial blood pH was 7.2. Given the constellation of biochemical and clinical findings a diagnosis of BRASH syndrome was made, though her blood pressure values at presentation were rather high (180/65-179/59 mmHg). The patient was rapidly stabilised with the administration of intravenous insulin and dextrose, fluid resuscitation, and zirconium cyclosilicate (SZC), followed by haemodialysis. Following the correction of the serum potassium to 4.7 mmol/L, a further ECG performed 6 hours later, showed a restoration of sinus rhythm with a rate of 65 bpm, normalization of the QRS duration. The digoxin and telmisartan were discontinued, and the patient was commenced on a calcium channel antagonist for hypertension. Clinicians should be alerted to patients who present with either a BRASH (shock) or BRAHH (hypertensive manifestation) where timely intervention is essential to avoid life-threatening brady-and tachyarrhythmias in these patients.

Thawing plateau time indicating the duration of phase transition from ice to water is the strongest predictor for long-term durable pulmonary vein isolation after cryoballoon ablation for atrial fibrillation-Data from the index and repeat procedures.

Introduction: This study aimed to clarify the relationship between the durability of pulmonary vein (PV) isolation and the time of phase transition from ice to water indicated by thawing plateau time in a cryoballoon ablation for atrial fibrillation (AF). Methods and results: In this retrospective study, 241 PVs from 71 patients who underwent a repeat AF ablation 526 (IQR: 412, 675) days after a cryoballoon ablation were analyzed. Reconnection was observed in 101 (41.9%) PVs of 53 patients (74.6%). Thawing plateau time (TimeTP) was defined as the time from 0°C to 10°C inside the balloon in the thawing period. Durable PV isolation was associated with significantly longer TimeTP compared with PV reconnection (26.0 vs. 11.0 s, P < 0.001). The proportion of durable PV isolations increased with TimeTP in a dose-proportional manner. The cut point for PV reconnection was TimeTP <15 s with a positive predictive value of 82.1% (sensitivity = 63.4%, specificity = 90.0%) while for durable PV isolation the cut point was TimeTP >25 s with a positive predictive value of 84.6% (sensitivity = 55.0%, specificity = 86.1%). In the analysis of multivariable logistic regression, location of PV reconnection (P < 0.01), TimeTP (P < 0.05) and thawing plateau integral (P < 0.01) were shown as independent predictors for durable PV isolation. Conclusion: TimeTP is an independent predictor for the durability of PV isolation, and it presents in a dose-proportional manner. TimeTP <15 s predicts long-term reconnection while TimeTP >25 s predicts durable PV isolation.

Ventricular arrhythmias originating from the aortomitral continuity: an uncommon variant of left ventricular outflow tract tachycardia.

AIMS: Ventricular arrhythmias arising from the fibrous rings have been demonstrated, but knowledge about the aortomitral continuity (AMC) as a source of the arrhytmias is still limited. The objective is to describe the characteristics of ventricular arrhythmias originating from the AMC in patients without structural heart disease. METHODS AND RESULTS: Ten patients with ventricular tachycardia (VT) and/or premature ventricular contractions, who had been successfully treated by catheter ablation at the AMC beneath the aortic valve, were enrolled. Clinical data and electrocardiographic characteristics were analysed. Three of the 10 patients had previously registered episodes of supraventricular tachycardia and had undergone catheter ablation of atrioventricular nodal reentrant tachycardia (AVNRT). In four patients with anterior AMC location, early R/S wave transition was found in the precordial leads, with equal R and S amplitudes in V2, rS in V1, and R in V3. In six patients whose VT arose from the middle part of the AMC, we demonstrated a special ('rebound') transition pattern, with which equal R and S amplitudes occurred in V2, and high R waves in V1 and V3. In the anterior AMC location, the S/R ratios in leads V1 and V2 were >1 and statistically significantly higher than those located in the middle (V1: 1.59 vs. 0.23, P< 0.001; V2: 1.52 vs. 0.41, P< 0.01). CONCLUSIONS: We report a series of ventricular arrhythmias arising from the AMC with different R/S wave transition patterns in the precordial leads on the electrocardiogram. There may be a relationship between ventricular arrhythmias from AMC and AVNRT.

Cardiovascular remodeling in obstructive sleep apnea: focus on arterial stiffness, left ventricular geometry and atrial fibrillation.

INTRODUCTION: Obstructive sleep apnea (OSA) is a common sleep-related breathing disorder that is associated with increased risk of cardiovascular disease. The main interest of this clinical review is to discuss the cardiovascular consequences of OSA with a special focus on left ventricular (LV) function and structure, arterial stiffness and atrial fibrillation. AREA COVERED: We present an overview of the definition, prevalence, and risk factors of OSA and outline the association between OSA and cardiovascular complications. We then briefly discuss echocardiographic assessment in OSA with focus on the left atrium and LV. Finally, we highlight the importance of adherence to continuous positive airway pressure (CPAP) therapy with regard to reducing the risk of cardiovascular disease. EXPERT COMMENTARY: Although OSA has a strong association with cardiovascular complications, it is often underdiagnosed and undertreated. Patients with resistant hypertension and atrial fibrillation with poor therapeutic success after cardioversion or catheter ablation should be more often screened for OSA. Patients with nocturnal adverse cardiovascular events (stroke, arrhythmias, angina, coronary events) should be closely assessed with regard to OSA, and if confirmed, timely treated by lifestyle modification, CPAP, and aggressive antihypertensive treatment. Adherence to CPAP in OSA patients is essential in terms of reducing the risk of cardiovascular events.

The impacts of contact force, power and application time on ablation effect indicated by serial measurements of impedance drop in both conventional and high-power short-duration ablation settings of atrial fibrillation.

BACKGROUND: This study aimed to clarify the interrelationship and additive effects of contact force (CF), power and application time in both conventional and high-power short-duration (HPSD) settings. METHODS: Among 38 patients with paroxysmal atrial fibrillation who underwent first-time pulmonary vein isolation, 787 ablation points were collected at the beginning of the procedure at separate sites. Energy was applied for 60 s under power outputs of 25, 30 or 35 W (conventional group), or 10 s when using 50 W (HPSD group). An impedance drop (ID) of 10 Ω was regarded as a marker of adequate lesion formation. RESULTS: ID ≥ 10 Ω could not be achieved with CF < 5 g under any power setting. With CF ≥ 5 g, ID could be enhanced by increasing power output or prolonging ablation time. ID for 30 and 35 W was greater than for 25 W (p < 0.05). Ablation with 35 W resulted in greater ID than with 30 W only when CF of 10-20 g was applied for 20-40 s (p < 0.05). Under the same power output, ID increased with CF level at different time points. The higher the CF, the shorter the time needed to reach ID of 10 Ω and maximal ID. ID correlated well with ablation index under each power, except for lower ID values at 25 W. ID with 50 W for 10 s was equivalent to that with 25 W for 40 s, but lower than that with 30 W for 40 s or 35 W for 30 s. CONCLUSIONS: CF of at least 5 g is required for adequate ablation effect. With CF ≥ 5g, CF, power output, and ablation time can compensate for each other. Time to reach maximal ablation effect can be shortened by increasing CF or power. The effect of HPSD ablation with 50 W for 10 s is equivalent to conventional ablation with 25 W for 40 s and 30-35 W for 20-30 s in terms of ID.

The Roles of Fractionated Potentials in Non-Macroreentrant Atrial Tachycardias Following Atrial Fibrillation Ablation: Recognition Beyond Three-Dimensional Mapping.

Introduction: Non-macroreentrant atrial tachycardia (nAT) following atrial fibrillation (AF) ablation is being increasingly reported. Many issues remain to be elucidated. We aimed to characterize the fractionated potentials (FPs) in nAT and introduce a new method of cross-mapping for clarifying their roles. Methods and Results: Forty-four nATs in 37 patients were enrolled and classified into focal AT (FAT, 12), microreentrant AT (MAT, 14), and small-loop-reentrant AT (SAT, 18) groups, according to activation pattern. FP was found on all targets except in nine FATs. The ratio of FP duration to AT cycle length (TCL) was different among groups (28 ± 7% in FAT, 53 ± 11% in MAT, and 42 ± 14% in SAT, p < 0.05), and ablation duration were longer in SATs (313 ± 298 vs. 111 ± 125 s, p < 0.05). The ratio of mappable cycle length to TCL was lower in the FAT group (63 ± 22% vs. 90 ± 9% and 89 ± 8%, p < 0.05). When cross-mapping was employed, trans-potential time differences in both longitudinal and transverse direction were longer around the culprit FP for MAT (p < 0.01). After Receiver Operating Characteristic curve analysis, it is best to adopt the sum of time difference ratios in both directions ≥60% as a cut-off value for discrimination of the FPs responsible for MAT with a sensitivity of 92% and specificity of 87%. Conclusions: FP could be found on target in most nATs following a previous AF ablation. The ratio of FP duration to TCL may help for differentiation. A simple method of cross-mapping could be employed to clarify the roles of FPs.

[Magnetic navigation for ablation of cardiac arrhythmias]. / Magnetstyrt ablasjonsbehandling av hjerterytmeforstyrrelser.

BACKGROUND: The first use of magnetic navigation for radiofrequency ablation of supraventricular tachycardias, was published in 2004. Subsequently, the method has been used for treatment of most types of tachyarrhythmias. This paper provides an overview of the method, with special emphasis on usefulness of a new remote-controlled magnetic navigation system. MATERIAL AND METHODS: The paper is based on our own scientific experience and literature identified through a non-systematic search in PubMed. RESULTS: The magnetic navigation system consists of two external electromagnets (to be placed on opposite sides of the patient), which guide an ablation catheter (with a small magnet at the tip of the catheter) to the target area in the heart. The accuracy of this procedure is higher than that with manual navigation. Personnel can be quickly trained to use remote magnetic navigation, but the procedure itself is time-consuming, particularly for patients with atrial fibrillation. The major advantage is a considerably lower radiation burden to both patient and operator, in some studies more than 50 %, and a corresponding reduction in physical strain on the operator. The incidence of procedure-related complications seems to be lower than that observed with use of manually operated ablation catheters. Work is ongoing to improve magnetic ablation catheters and methods that can simplify mapping procedures and improve efficacy of arrhythmia ablation. The basic cost for installing a complete magnetic navigation laboratory may be three times that of a conventional electrophysiological laboratory. INTERPRETATION: The new magnetic navigation system has proved to be applicable during ablation for a variety of tachyarrhythmias, but is still under development.

Systemic Cardiac Troponin T Associated With Incident Atrial Fibrillation Among Patients With Suspected Stable Angina Pectoris.

Higher concentrations of cardiac troponin T are associated with coronary artery disease (CAD) and adverse cardiovascular prognosis. The relation with incident atrial fibrillation (AF) is less explored. We studied this association among 3,568 patients evaluated with coronary angiography for stable angina pectoris without previous history of AF. The prospective association between high-sensitivity cardiac troponin T (hs-cTnT) categories (≤3 ng/L; n = 1,694, 4-9; n = 1,085, 10 to 19; n = 614 and 20 to 30; n = 175) and incident AF and interactions with the extent of CAD were studied by Kaplan-Meier plots and Cox regression. Risk prediction improvements were assessed by receiver operating characteristic area under the curve (ROC-AUC) analyses. During median (25 to 75 percentile) 7.3 (6.3 to 8.6) years of follow-up 412 (11.5%) were diagnosed with AF. In a Cox model adjusted for age, gender, body mass index, hypertension, diabetes mellitus, smoking, estimated glomerular filtration rate, and left ventricular ejection fraction, hazard ratios (HRs) (95% confidence intervals [CIs]) were 1.53 (1.16 to 2.03), 2.03 (1.49 to 2.78), and 2.15 (1.40 to 3.31) when comparing the second, third, and fourth to the first hs-cTnT group, respectively (P for trend <0.000001). The strongest association between hs-cTnT levels and incident AF was found among patients without obstructive CAD (Pint = 0.024) and adding hs-cTnT to established AF risk factors improved risk classification slightly (ΔROC 0.006, p = 0.044). In conclusion, in patients with suspected stable angina higher levels of hs-cTnT predicted increased risk of incident AF. This was most pronounced in patients without obstructive CAD suggesting an association not mediated by coronary disease.

Spatial relationships between the pulmonary veins and sites of complex fractionated atrial electrograms during atrial fibrillation.

BACKGROUND: Pulmonary vein (PV) isolation is used for the treatment of atrial fibrillation (AF). Complex fractionated atrial electrogram (CFAE) mapping has been introduced to guide AF ablation. However, the spatial relationship between PV and CFAE is not well defined. METHODS AND RESULTS: The study included 21 patients (mean age 57 +/- 11 years, 17 men, 14 paroxysmal, two persistent, and five long-standing persistent AF) referred for PV isolation. Electrograms were sampled for 8 seconds at each site during stable AF (13 induced). High-frequency was defined as <80 ms of CFAE value. The distance between CFAE and the nearest PV ostium was measured. The PV ostia and antra were demarcated by fluoroscopy guidance and endocardial reconstruction. Among 82 PV mapped (left common four, superior 17, inferior 17; right superior 21, inferior 21, middle 2), 52.4% and 25.6% of high-frequency CFAE were located on the anterior and posterior walls, respectively, inside the PV or at the ostium. No high-frequency CFAE was observed in two out of 60 and one out of 20 PV anteriorly, versus seven out of 60 and 11 out of 20 PV (P < 0.001) posteriorly, in paroxysmal and persistent AF, respectively. In the PV with high-frequency CFAE, the mean shortest distances to the PV ostia in paroxysmal versus persistent AF were 2.7 +/- 5.1 versus 7.4 +/- 5.4 mm anteriorly (P < 0.01), and 6.5 +/- 6.4 versus 9.4 +/- 8.4 mm posteriorly (ns). CONCLUSIONS: During PV isolation, extending the ablation lesions by up to 10 mm from the PV ostia might cover most high-frequency CFAE around the PV antra. High-frequency CFAE were more often located in the PV ostia in paroxysmal than in persistent AF.

Atrio-pulmonary vein conduction delay during pulmonary vein isolation for atrial fibrillation is related to vein anatomy, age, and focal activity.

BACKGROUND: During pulmonary vein isolation for treatment of atrial fibrillation (AF), a significant delay in atrio-pulmonary vein (PV) conduction is often observed. We sought to investigate this conduction delay in various PV in individual patients. METHODS: We studied 385 AF patients (mean age: 54 +/- 11 years, 74 women) who underwent segmental PV isolation (PVI). A circular decapolar catheter was used to record electrograms at the PV ostia. The time delay from local atrial potential to PV potential was measured in each vein. Conduction delay (CD) was defined as the longest time interval >20 ms observed during PVI. RESULTS: For patients treated for the first time, CD was more frequently observed in the left common and the right and left superior PVs (84.2%, 67.9%, and 66.2%, respectively) and less frequently in the left and right inferior and right middle PVs (54.3%, 40.0%, and 30.8%, respectively). Veins with CD required more ablation applications (12.4 vs 9.9) and a higher ablated segmental fraction (72.3% vs 63.7%). CD was observed in 75.2% (109/145) of the PVs in which focal activity was detected. Older patients had a higher incidence of PVs with CD than younger patients. There were no gender differences. CONCLUSIONS: The incidence of CD was highest in the left common and superior PVs, in older patients and in PVs with focal activity. PVs with CD required more ablation applications and a larger area of ablation around the ostia. These observations were not found during repeat procedures.