ACC/AHA/ESC Guidelines for the Management of Patients With Supraventricular Arrhythmias—Executive Summary

[Management of syncope in clinical practice : What has changed according to the new ESC guidelines 2018?]

Syncope is a common problem in clinical practice, which affects approximately 1% of patients admitted to European emergency departments. The clinical practice guidelines for the diagnosis and management of syncope published by the European Society of Cardiology (ESC) are based on the newest scientific data in the field and have provided clinical cardiologists with a structured therapeutic approach for affected patients over many years. The previous ESC guidelines on syncope were published in 2009 and are compared to the most recent edition, which was published in 2018. This review summarizes the most important innovations with respect to the diagnostic principles and treatment of syncope. The initial assessment of the patient and the risk stratification in the emergency department are the focus of the review. Another important topic that is adequately covered in the current guidelines is the rising significance of implantable loop recorders for the evaluation of unexplained syncope and the assessment of potential indications for a definitive treatment with a pacemaker or implantable cardioverter defibrillator (ICD). Additional changes involve the evidence level with respect to the use of other diagnostic (ECG monitoring, tilt testing) and therapeutic measures (indications for pacemaker implantation, catheter ablation of tachycardiac rhythm disorders).

A simplified approach for evaluating sustained slow pathway conduction for diagnosis and treatment of atrioventricular nodal reentry tachycardia in children and adults

PURPOSE

During incremental atrial pacing in patients with atrioventricular nodal reentrant tachycardia, the PR interval often exceeds the RR interval (PR > RR) during stable 1:1 AV conduction. However, the PR/RR ratio has never been evaluated in a large group of patients with pacing from the proximal coronary sinus and after isoproterenol challenge. Our study validates new site of pacing and easier method of identification of PR > RR.

MATERIAL AND METHODS

A prospective protocol of incremental atrial pacing from the proximal coronary sinus was carried out in 398 patients (AVNRT-228 and control-170). The maximum stimulus to the Q wave interval (S-Q = PR), SS interval (S-S), and Q-Q (RR) interval were measured at baseline and 10 min after successful slow pathway ablation and after isoproterenol challenge (obligatory).

RESULTS

The mean maximum PR/RR ratios at baseline were 1.17 ± 0.24 and 0.82 ± 0.13 (p < 0.00001) in the AVNRT and controls respectively. There were no PR/RR ratios ≥1 at baseline and after isoproterenol challenge in 12.3% of the AVNRT group and in 95.9% of the control group (p < 0.0001). PR/RR ratios ≥1 were absent in 98% of AVNRT cases after slow pathway ablation/modification in children and 99% of such cases in adults (P = NS). The diagnostic performance of PR/RR ratio evaluation before and after isoproterenol challenge had the highest diagnostic performance for AVNRT with PR/RR > = 1 (sensitivity: 88%, specificity: 96%, PPV-97%, NPV-85%).

CONCLUSIONS

The PR/RR ratio is a simple tool for slow pathway substrate and AVNRT evaluation. Eliminating PR/RR ratios ≥1 may serve as a surrogate endpoint for slow pathway ablation in children and adults with AVNRT.

Antidromic Atrioventricular Reentry Tachycardia with Wolff Parkinson White Syndrome: A Rare Beast

Orthodromic atrioventricular reentrant tachycardia (AVRT) is the second-most-common form of supraventricular tachycardia (SVT) and is inducible in approximately 55% of individuals with Wolff Parkinson White (WPW) syndrome. Antidromic AVRT, where the accessory atrioventricular connection is used as the antegrade limb and the atrioventricular node serves as the retrograde limb of the circuit, has been clinically documented in less than 5% of patients with WPW syndrome and may be induced in less than 10% of these WPW cases in the electrophysiology laboratory. Left lateral pathways are considered more frequent and septal locations are less common when associated with antidromic AVRT.

We report a case of 21-year-old male with a history of WPW syndrome who had undergone a prior electrophysiology study in 2010 at an outlying facility, documenting an anteroseptal accessory pathway near the His bundle along with an unsuccessful attempt at radiofrequency ablation at that time. No supraventricular tachycardia was induced at that previous study. The surface electrocardiogram (ECG), at this time, was consistent with the anteroseptal WPW pattern. The patient now presented with a complaint of intermittent palpitations with no definitive trigger. He also described a recent syncopal episode while walking inside his home. His physical exam and all lab work were within normal limits for his age. He underwent a repeat electrophysiology (EP) study where the baseline PR interval was 62 milliseconds and the QRS duration was 172 milliseconds in a pre-excited pattern. There was found to be an antegrade-only conducting accessory pathway at the anteroseptal region near the His bundle. Antegrade AVRT was induced with a single ventricular extra stimulus while on 2 mcg/min isoproterenol. Cryoablation was performed in a position slightly posterior to the His bundle, which successfully resolved the accessory pathway conduction. First-degree atrioventricular (AV) block was noted in the sinus rhythm with a PR interval of 226 milliseconds post-cryoablation. There was no recurrence of accessory pathway conduction on follow-up ECG 24 hours post-cryoablation.

Antidromic AVRT is a very rare finding in WPW syndrome during an EP study. Catheter ablation is the treatment of choice for patients who have symptomatic WPW syndrome. Catheter ablation can be especially challenging when the accessory pathway is in close proximity to the normal conduction pathways. The prognostic significance of inducible antidromic AVRT is controversial in asymptomatic patients and limited data indicate it may be a poor prognostic sign in children. In adults, the prognostic significance is not well-established. Cryoablation is an option for the ablation of accessory pathways that are close to the normal conduction pathways. “Cryomapping” is designed to have precise ablation and to reassure the absence of complications.

Flecainide Toxicity: A Case Report and Systematic Review of its Electrocardiographic Patterns and Management

In the setting of flecainide toxicity, supraventricular tachycardia can manifest as a bizarre right or left bundle branch block, sometimes with a northwest axis, and can easily be mistaken for ventricular tachycardia leading to inappropriate therapy. We conducted a comprehensive literature review for cases of flecainide toxicity. We found 21 articles of flecainide toxicity in adult patients in which 22 ECG tracings were published. In patients with flecainide toxicity and QRS duration ≤ 200 ms, the ECGs were more likely to show RBBB, visible P waves (p = 0.03), and shorter QT (p = 0.02) and QTc intervals (p = 0.004). With QRS duration > 200 ms, the ECGs were more likely to show LBBB, loss of P waves, a northwest axis (p = 0.01), and longer QT and QTc intervals. Deaths were reported only in patients with QRS duration >200 ms, and the outcome of death or requirement for mechanical circulatory support was more prevalent in patients with a QRS duration > 200 ms [2/13 (15.4 %) vs. 6/10 (60 %), p = 0.04]. In patients with access to the medication, flecainide toxicity should be suspected with: (1) broad QRS, (2) RBBB morphology with QRS ≤ 200 ms; RBBB or LBBB morphology with QRS ≥ 200 ms (3) HR out of proportion to the degree of hemodynamic instability. The duration of the QRS interval is prognostic, with mortality and the requirement for mechanical circulatory support being more common in patients with a QRS > 200 ms.

Clinical impact of "pure" empirical catheter ablation of slow-pathway in patients with non-ECG documented clinical on-off tachycardia

Background

Catheter ablation of slow-pathway (CaSP) has been reported to be effective in patients with dual atrioventricular nodal conduction properties (dcp-AVN) and clinical ECG documentation but without the induction of tachycardia during electrophysiological studies (EPS). However, it is unknown whether CaSP is beneficial in the absence of pre-procedural ECG documentation and without the induction of tachycardia during EPS. The aim of this study was to evaluate long-term results after a “pure” empirical CaSP (peCaSP).

Methods

334 consecutive patients who underwent CaSP (91 male, 47.5 ± 17.6 years) were included in this study. Sixty-three patients (19%) who had no pre-procedural ECG documentation, and demonstrated dcp-AVN with a maximum of one echo-beat were assigned to the peCaSP group. The remaining 271 patients (81%) were assigned to the standard CaSP group (stCaSP). Clinical outcomes of the two groups were compared, based on ECG documented recurrence or absence of tachycardia and patients’ recorded symptoms.

Results

CaSP was performed in all patients without any major complications including atrioventricular block. During follow-up (909 ± 435 days), 258 patients (77%) reported complete cessation of clinical symptoms. There was no statistically significant difference in the incidence of AVNRT recurrence between the peCaSP and stCaSP groups (1/63 [1.6%] vs 3/271 [1.1%], P = 0.75). Complete cessation of clinical symptoms was noted significantly less frequently in patients after peCaSP (39/63 [62%] vs 219/271 [81%], P = 0.0013). The incidence of non-AVNRT atrial tachyarrhythmias (AT) was significantly higher in patients after peCaSP (5/63 [7.9%] vs 1/271 [0.4%], P = 0.0011).

Conclusion

A higher incidence of other AT and subjective symptom persistence are demonstrated after peCaSP, while peCaSP improves clinical symptoms in 60% of patients with non-documented on–off tachycardia.

Spectroscopic photoacoustic imaging of radiofrequency ablation in the left atrium

Catheter-based radiofrequency ablation for atrial fibrillation has long-term success in 60-70% of cases. A better assessment of lesion quality, depth, and continuity could improve the procedure's outcome. We investigate here photoacoustic contrast between ablated and healthy atrial-wall tissue in vitro in wavelengths spanning from 410 nm to 1000 nm. We studied single- and multi-wavelength imaging of ablation lesions and we demonstrate that a two-wavelength technique yields precise detection of lesions, achieving a diagnostic accuracy of 97%. We compare this with a best single-wavelength (640 nm) analysis that correctly identifies 82% of lesions. We discuss the origin of relevant spectroscopic features and perspectives for translation to clinical imaging.

Localizing the Accessory Pathway in Ventricular Preexcitation Patients Using a Score Based Algorithm

Objectives: Clinical data was analyzed to find an efficient way to localize the accessory pathway in patients with ventricular preexcitation.

Methods: The delta wave morphologies and ablation sites of 186 patients who underwent catheter ablation were analyzed and an algorithm (“locAP”) to localize the accessory pathway was developed from the 84 data sets with a PQ interval ≤ 0.12 s and a QRS width ≥ 0.12 s. Fifty additional patients were included for a prospective validation. The locAP algorithm ranks 13 locations according to the likelihood that the accessory pathway is localized there. The algorithm is based on the locAP score which uses the standardized residuals of the available data sets.

Results: The locAP algorithm’s accuracy is 0.54 for 13 locations, with a sensitivity of 0.84, a specificity of 0.97, and a positive likelihood ratio of 24.94. If the two most likely locations are regarded, the accuracy rises to 0.79, for the three most likely locations combined the accuracy is 0.82. This new algorithm performs better than Milstein’s, Fitzpatrick’s, and Arruda’s algorithm both in the original study population as well as in a prospective study.

Conclusions: The locAP algorithm is a valid and valuable tool for clinical practice in a cardiac electrophysiology laboratory. It could be shown that use of the locAP algorithm is favorable over the localizing algorithms that are in clinical use today.

Extracellular Adenosine Stimulates Vacuolar ATPase-Dependent Proton Secretion in Medullary Intercalated Cells

Acidosis is an important complication of AKI and CKD. Renal intercalated cells (ICs) express the proton pumping vacuolar H⁺-ATPase (V-ATPase) and are extensively involved in acid-base homeostasis. H⁺ secretion in type A intercalated cells (A-ICs) is regulated by apical vesicle recycling and stimulated by cAMP. In other cell types, cAMP is increased by extracellular agonists, including adenosine, through purinergic receptors. Adenosine is a Food and Drug Administration-approved drug, but very little is known about the effect of adenosine on IC function. Therefore, we investigated the role of adenosine in the regulation of V-ATPase in ICs. Intravenous treatment of mice with adenosine or agonists of ADORA2A and ADORA2B purinergic P1 receptors induced V-ATPase apical membrane accumulation in medullary A-ICs but not in cortical A-ICs or other IC subtypes. Both receptors are located in A-IC apical membranes, and adenosine injection increased urine adenosine concentration and decreased urine pH. Cell fractionation showed that adenosine or an ADORA2A or ADORA2B agonist induced V-ATPase translocation from vesicles to the plasma membrane and increased protein kinase A (PKA)-dependent protein phosphorylation in purified medullary ICs that were isolated from mice. Either ADORA2A or ADORA2B antagonists or the PKA inhibitor mPKI blocked these effects. Finally, a fluorescence pH assay showed that adenosine activates V-ATPase in isolated medullary ICs. Our study shows that medullary A-ICs respond to luminal adenosine through ADORA2A and ADORA2B receptors in a cAMP/PKA pathway-dependent mechanism to induce V-ATPase-dependent H⁺ secretion.

Differences among western European countries in anticoagulation management of atrial fibrillation

Due to improved implementation of guidelines, new scoring approaches to improve risk categorisation, and introduction of novel oral anticoagulants, medical management of patients with atrial fibrillation (AF) is continuously improving. The PREFER in AF registry enrolled 7,243 consecutive patients with ECG-confirmed AF in seven European countries in 2012–2013 (mean age: 71.5 ± 10.7 years; 60.1% males; mean CHA2DS 2 -VASc score: 3.4). While patient characteristics were generally homogeneous across countries, anticoagulation management showed important differences: the proportion of patients taking vitamin K antagonists (VKAs) varied between 86.0% (in France) and 71.4% (in Italy). Warfarin was used predominantly in the UK and Italy (74.9% and 62.0%, respectively), phenprocoumon in Germany (74.1%), acenocoumarol in Spain (67.3%), and fluindione in France (61.8 %). The major sites for international normalised ratio (INR) measurements were biology laboratories in France anticoagulation clinics in Italy, Spain, and the UK, and physicians’ offices or self-measurement in Germany. Temporary VKA discontinuation and bridging with other anticoagulants was frequent (at least once in the previous 12 months for 22.9% of the patients, on average; ranging from 29.7% in Germany to 14.9% in the UK). Time in therapeutic range (TTR), defined as at least two of the last three available INR values between 2.0–3.0 prior to enrolment, ranged from 70.3% in Spain to 81.4% in Germany. TTR was constantly overestimated by physicians. While the type and half-lives of VKA as well as the mode of INR surveillance differed, overall quality of anticoagulation management by TTR was relatively homogenous in AF patients across countries.

Cardioversions and Transthoracic Echocardiography

Patients with atrial fibrillation and flutter routinely require transesophageal echocardiography with cardioversion. It is not uncommon to encounter patients with reduced ejection fractions, coronary artery disease, prior cardiac surgery, or obstructive sleep apnea. The anesthesiologist must carefully evaluate the patient and any available laboratory and study findings to assess for potential complications after anesthesia. Appropriate anesthetics must be chosen based on the preoperative evaluation. Additionally, because most of these cases are done without a secured airway, emergency medications and airway equipment must be readily available.

Congenitally corrected transposition of great vessels with infundibular pulmonary stenosis with ventricular septal defect, presenting with atypical atrioventricular nodal reentrant tachycardia: a rare association

Congenitally corrected transposition of great vessels (CCTGV) is a rare congenital heart disease (CHD) accounting for <1% of CHDs. CCTGV with infundibular pulmonary stenosis (PS) with ventricular septal defect (VSD) is part of Fallot’s physiology. It is known to be associated with bradyarrhythmias like atrioventricular (AV) blocks, and acquired complete AV block occurs at a rate of 2% per year. Patients can have left-sided accessory pathways, which may cause atrioventricular reentrant tachycardia (AVRT). Tachyarrhythmias like atrioventricular nodal reentrant tachycardia (AVNRT) are very rare in such patients. A 30-year-old woman, a known case of CCTGV with PS with VSD, not corrected surgically and not on any drugs, presented with the syndrome of paroxysmal supraventricular tachycardia without hemodynamic compromise. Electrocardiogram showed atypical AVNRT. She was pharmacologically cardioverted to normal sinus rhythm with adenosine. CTGV with PS with VSD known to be associated with AV blocks, and preexcitation can sometimes present with atypical AVNRT.

Characteristic features of patients with multiple accessory pathways

Objective Only limited clinical and electrophysiological data concerning patients (pts) with multiple accessory pathways (MAP) in comparison to large control groups are available. The aim of our study was to analyse these data from the largest cohort of patients with multiple accessory pathways and a large control group. Method and results We analysed data from pts with MAP (group 1) and pts with a single accessory pathway (AP) (group 2) referred for radiofrequency catheter ablation (RFCA) at our tertiary centre. Group 1 consisted of 124 pts (M 62.10%, mean age 33.00 ± 5.26) with MAP and RFCA. Group 2 consisted of 376 pts (M 51.20%, mean age 35.87 ± 16.15) with a single accessory pathway and RF ablation. Group 1 exhibited a higher incidence of overt APs (P < 0.0001), Ebstein anomaly (P = 0.001), ventricular fibrillation (P = 0.012), antidromic atrioventricular re-entrant tachycardia (A AVRT) (P = 0.025) and male gender (P = 0.038). The mean age at the first documented atrioventricular re-entrant tachycardia (AVRT) episode was lower in pts with MAP than in pts with single APs: 16.79 ± 13.41 vs 20.84 ± 14.29, respectively (P = 0.001). Concealed accessory pathways (P < 0.0001) occurred more frequently in the control group. Group 1 had more right-lateral (P = 0.0001), mid-septal (P = 0.0001), left-posterior (P = 0.01), left-anterior (P = 0.013) and left-lateral localizations of AP (P < 0.037). Conclusions The MAP group included statistically significantly more men, Ebstein anomaly and overt APs. The mean age of the first episode of atrioventricular re-entrant tachycardia was lower in pts with MAP. Certain distribution patterns are apparent for single and MAP. Pts with MAP are at higher risk of VF and antidromic atrioventricular re-entrant tachycardia.

Catheter ablation of organized atrial arrhythmias in orthotopic heart transplantation

BACKGROUND

Organized atrial arrhythmias (OAAs) are common after orthotopic heart transplantation (OHT). Some controversies remain about their clinical presentation, relationship with atrial anastomosis and electrophysiologic features. The objectives of this retrospective study were to determine the mechanisms of OAAs after OHT and describe the outcomes of radiofrequency catheter ablation (RFCA).

METHODS

Thirty consecutive transplanted patients (mean age 48 ± 17 years, 86.6% male) underwent 3-dimensional electroanatomic mapping and RFCA of their OAA from 2004 to 2012 at our center.

RESULTS

Twenty-two patients had biatrial anastomosis and 8 had bicaval anastomosis. Macro-reentry was the arrhythmia mechanism for 96% of patients. The electrophysiologic diagnoses were: cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL) in 93% of patients (n = 28); perimitral AFL in 3% (n = 1); and focal atrial tachycardia (FAT) in 3% (n = 1). In 5 patients with biatrial anastomosis, a right FAT was inducible. Primary RFCA success was obtained in 93% of patients. Mean follow-up time was 39 ± 26.8 months. Electrical repermeation between recipient and donor atria, present in 20% of patients (n = 6), did not account for any of the OAAs observed. Survival without OAA relapse at 12, 24 and 60 months was 93%, 89% and 79%, respectively.

CONCLUSIONS

CTI-dependent AFL accounted for most instances of OAA after OHT, regardless of anastomosis type. Time from transplantation to OAA was shorter with bicaval than with biatrial anastomosis. RFCA was safe and provided good long-term results.

Conventional Acupuncture for Cardiac Arrhythmia: A Systematic Review of Randomized Controlled Trials

OBJECTIVE

To exam the effect and safety of conventional acupuncture (CA) on cardiac arrhythmia.

METHODS

Nine medical databases were searched until February 2016 for randomized controlled trials. Heterogeneity was measured by Cochran Q test. Meta-analysis was conducted if I² was less than 85% and the characteristics of included trials were similar.

RESULTS

Nine qualified studies involving 638 patients were included. Only 1 study had definitely low risk of bias, while 7 trials were rated as unclear and 1 as high. Meta-analysis of CA alone did not have a significant benefit on response rate compared to amiodarone in patients with atrial fibrillation (Af) and atrial flutter (AF) [relative risk (RR): 1.09; 95% confidence interval (CI): 0.79-1.49; P=0.61; I²=61%, P=0.11]. However, 1 study with higher methodological quality detected a lower recurrence rate of Af in CA alone as compared with sham acupuncture plus no treatment, and benefits on ventricular rate and time of conversion to normal sinus rhythm were found in CA alone group by 1 study, as well as the response rate in CA plus deslanoside group by another study. Meta-analysis of CA plus anti-arrhythmia drug (AAD) was associated with a significant benefit on the response rate when compared with AAD alone in ventricular premature beat (VPB) patients (RR, 1.19, 95% CI: 1.05-1.34; P=0.005; I²=13%, P=0.32), and an improvement in quality-of-life score (QOLS) of VPB also showed in 1 individual study. Besides, a lower heart rate was detected in the CA alone group by 1 individual study when compared with no treatment in sinus tachycardia patients (MD-21.84 [-27.21,-16.47]) and lower adverse events of CA alone were reported than amiodarone.

CONCLUSIONS

CA may be a useful and safe alternative or additive approach to AADs for cardiac arrhythmia, especially in VPB and Af patients, which mainly based on a pooled estimate and result from 1 study with higher methodological quality. However, we could not reach a robust conclusion due to low quality of overall evidence.

Association of Paroxysmal Supraventricular Tachycardia with Ischemic Stroke: A National Case-Control Study

BACKGROUND AND PURPOSE

Cardioembolic stroke accounts for approximately 15%-20% of all ischemic strokes. Atrial fibrillation constitutes one-half to two-thirds of all cardioembolic stroke events. The association of paroxysmal supraventricular tachycardia (PSVT) with ischemic stroke remains unclear. A national case-control study was conducted to identify the risk factors, including PSVT, for ischemic stroke in Taiwan.

METHODS

We designed a national case-control study comprising patients diagnosed with ischemic stroke (n = 5633) from 1997 to 2011; each patient from the case group was randomly matched with the control group (n = 30,895) in Taiwan. Data were retrospectively collected from Taiwan's National Health Insurance Research Database, which contains not only claims data on hospitalization, emergency room visits, and outpatient department visits, but also patient characteristics.

RESULTS

Logistic regression analysis was used to identify the risk factors for ischemic stroke. Independent risk factors for ischemic stroke included age (in 5-year intervals; odds ratio [OR], 1.76; 95% confidence interval [CI], 173-1.78), the male sex (versus the female sex; OR, 1.88; 95% CI, 1.74-2.01), chronic kidney disease (OR, 3.09; 95% CI, 2.67-3.57), PSVT (OR, 2.05; 95% CI, 1.30-3.19), and aspirin use (OR, .04; 95% CI, .03-0.05).

CONCLUSIONS

Our study is the first in Taiwan to identify PSVT as a significant risk factor for ischemic stroke. New antithrombotic regimens, including aspirin, can be recommended for the primary prevention of stroke and for reducing the burden of stroke for patients with PSVT.

Use of Proton-Pump Inhibitors Predicts Heart Failure and Death in Patients with Coronary Artery Disease

OBJECTIVES

Proton-pump inhibitors (PPIs) seem to increase the incidence of cardiovascular events in patients with coronary artery disease (CAD), mainly in those using clopidogrel. We analysed the impact of PPIs on the prognosis of patients with stable CAD.

METHODS

We followed 706 patients with CAD. Primary outcome was the combination of secondary outcomes. Secondary outcomes were 1) acute ischaemic events (any acute coronary syndrome, stroke, or transient ischaemic attack) and 2) heart failure (HF) or death.

RESULTS

Patients on PPIs were older [62.0 (53.0-73.0) vs. 58.0 (50.0-70.0) years; p = 0.003] and had a more frequent history of stroke (4.9% vs. 1.1%; p = 0.004) than those from the non-PPI group, and presented no differences in any other clinical variable, including cardiovascular risk factors, ejection fraction, and therapy with aspirin and clopidogrel. Follow-up was 2.2±0.99 years. Seventy-eight patients met the primary outcome, 53 developed acute ischaemic events, and 33 HF or death. PPI use was an independent predictor of the primary outcome [hazard ratio (HR) = 2.281 (1.244-4.183); p = 0.008], along with hypertension, body-mass index, glomerular filtration rate, atrial fibrillation, and nitrate use. PPI use was also an independent predictor of HF/death [HR = 5.713 (1.628-20.043); p = 0.007], but not of acute ischaemic events. A propensity score showed similar results.

CONCLUSIONS

In patients with CAD, PPI use is independently associated with an increased incidence of HF and death but not with a high rate of acute ischaemic events. Further studies are needed to confirm these findings.

[Urgent cardiovascular conditions in dental practice]

Cardiovascular diseases rank first in disease patterns and their prevalence increases in most countrie, including Russian Federation. The paper presents guidelines for approaches prevention of urgent cardiovascular conditions and measures to provide first medical aid which will help avoid the negative effects in the acute clinical situations.

Identifying the third dimension in 2D fluoroscopy to create 3D cardiac maps

Three-dimensional cardiac mapping is important for optimal visualization of the heart during cardiac ablation for the treatment of certain arrhythmias. However, many hospitals and clinics worldwide cannot afford the high cost of the current mapping systems. We set out to determine if, using predefined algorithms, comparable 3D cardiac maps could be created by a new device that relies on data generated from single-plane fluoroscopy and patient recording and monitoring systems, without the need for costly equipment, infrastructure changes, or specialized catheters. The study included phantom and animal experiments to compare the prototype test device, Navik 3D, with the existing CARTO 3 System. The primary endpoint directly compared: (a) the 3D distance between the Navik 3D-simulated ablation location and the back-projected ground truth location of the pacing and mapping catheter electrode, and (b) the same distance for CARTO. The study's primary objective was considered met if the 95% confidence lower limit was greater than 0.75% for the Navik 3D-CARTO difference between the 2 distances, or less than or equal to 2 mm. Study results showed that the Navik 3D performance was equivalent to the CARTO system, and that accurate 3D cardiac maps can be created using data from equipment that already exists in all electrophysiology labs.

Asymptomatic Intradialytic Supraventricular Arrhythmias and Adverse Outcomes in Patients on Hemodialysis

BACKGROUND AND OBJECTIVES

Supraventricular arrhythmias are associated with high morbidity and mortality. Nevertheless, this condition has received little attention in patients on hemodialysis. The objective of this study was to analyze the incidence of intradialysis supraventricular arrhythmia and its long-term prognostic value.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We designed an observational and prospective study in a cohort of patients on hemodialysis with a 10-year follow-up period. All patients were recruited for study participation and were not recruited for clinical indications. The study population comprised 77 patients (42 men and 35 women; mean age =58±15 years old) with sinus rhythm monitored using a Holter electrocardiogram over six consecutive hemodialysis sessions at recruitment.

RESULTS

Hypertension was present in 68.8% of patients, and diabetes was present in 29.9% of patients. Supraventricular arrhythmias were recorded in 38 patients (49.3%); all of these were short, asymptomatic, and self-limiting. Age (hazard ratio, 1.04 per year; 95% confidence interval, 1.00 to 1.08) and right atrial enlargement (hazard ratio, 4.29; 95% confidence interval, 1.30 to 14.09) were associated with supraventricular arrhythmia in the multivariate analysis. During a median follow-up of 40 months, 57 patients died, and cardiovascular disease was the main cause of death (52.6%). The variables associated with all-cause mortality in the Cox model were age (hazard ratio, 1.04 per year; 95% confidence interval, 1.00 to 1.08), C-reactive protein (hazard ratio, 1.04 per 1 mg/L; 95% confidence interval, 1.00 to 1.08), and supraventricular arrhythmia (hazard ratio, 3.21; 95% confidence interval, 1.29 to 7.96). Patients with supraventricular arrhythmia also had a higher risk of nonfatal cardiovascular events (hazard ratio, 4.32; 95% confidence interval, 2.11 to 8.83) and symptomatic atrial fibrillation during follow-up (hazard ratio, 17.19; 95% confidence interval, 2.03 to 145.15).

CONCLUSIONS

The incidence of intradialysis supraventricular arrhythmia was high in our hemodialysis study population. Supraventricular arrhythmias were short, asymptomatic, and self-limiting, and although silent, these arrhythmias were independently associated with mortality and cardiovascular events.

Diagnostic Accuracy of Several Electrocardiographic Criteria for the Prediction of Atrioventricular Nodal Reentrant Tachycardia

BACKGROUND AND AIMS

Atrioventricular nodal reentrant tachycardia (AVNRT) is the most common form of paroxysmal supraventricular tachycardia (SVT) whose diagnosis can be strongly suspected based on the surface eletrocardiogram alone. The purpose of this study is to determine the diagnostic accuracy of several electrocardiographic (ECG) criteria for the prediction of AVNRT.

METHODS

Between November 2010 and January 2014, a total of 256 patients who underwent electrophysiological testing (EP) with regular, paroxysmal and narrow QRS complex tachycardia were prospectively enrolled. We classified the ECG recordings during tachycardia for the presence of the following criteria: a) classical ECG findings of pseudo S wave in inferior leads and/or pseudo r' wave in lead V1, b) notch in lead aVL, c) no retrograde P waves visible during tachycardia; d) pseudo r' wave in lead aVR, e) notch in lead D1, f) any deflection after 100 ms of the QRS complex during tachycardia.

RESULTS

On multivariate analysis, independent predictors of AVNRT diagnosis were female sex (OR 4.17; 95% CI [2.11-8.24]; p <0.001), age >60 years (OR 3.53; 95% CI [1.25-9.96]; p = 0.017) and the classical ECG criteria (OR 7.41; 95% CI [3.62-15.17]; p <0.001).

CONCLUSIONS

Female, age >60 years and the classical ECG criteria were the independent predictors of AVNRT diagnosis. Although several of the ECG criteria for AVNRT diagnosis showed acceptable sensitivities and specificities, they do not improve its accuracy.

Accuracy of the Electrocardiogram in Localizing the Accessory Pathway in Patients with Wolff-Parkinson-White Pattern

BACKGROUND

There are currently several electrocardiographic algorithms to locate the accessory pathway (AP) in patients with Wolff-Parkinson-White (WPW) syndrome.

OBJECTIVE

To compare the ability of electrocardiographic algorithms in identifying the location of the AP in patients with WPW pattern referred for ablation.

METHODS

Observational, cross-sectional, retrospective study with 111 patients with WPW syndrome referred for AP ablation. The electrocardiogram (ECG) obtained prior to the ablation was analyzed by an experienced observer who consecutively applied seven algorithms to identify non-invasively the AP. We then compared the location estimated with this assessment with that obtained in the electrophysiological study and calculated the agreement rates.

RESULTS

Among the APs, 59 (53.15%) were distributed around the mitral annulus and the remaining 52 (46.85%) were located around the tricuspid annulus. The overall absolute accuracy of the algorithms evaluated varied between 27% and 47%, increasing to between 40% and 76% when we included adjacent locations. The absolute agreement rate by AP location was 2.00-52.20% for septal APs (n = 51), increasing to 5.90-90.20% when considering adjacent locations; 7.70-69.20% for right APs (n = 13), increasing to 42.90-100% when considering adjacent locations; and 21.70-54.50% for left APs (n = 47), increasing to 50-87% when considering adjacent locations.

CONCLUSION

The agreement rates observed for the analyzed scores indicated a low discriminative ability of the ECG in locating the AP in patients with WPW.

Role of protein phosphatase inhibitor-1 in cardiac beta adrenergic pathway

Phosphoproteomic studies have shown that about one third of all cardiac proteins are reversibly phosphorylated, affecting virtually every cellular signaling pathway. The reversibility of this process is orchestrated by the opposing enzymatic activity of kinases and phosphatases. Conversely, imbalances in subcellular protein phosphorylation patterns are a hallmark of many cardiovascular diseases including heart failure and cardiac arrhythmias. While numerous studies have revealed excessive beta-adrenergic signaling followed by deregulated kinase expression or activity as a major driver of the latter cardiac pathologies, far less is known about the beta-adrenergic regulation of their phosphatase counterparts. In fact, most of the limited knowledge stems from the detailed analysis of the endogenous inhibitor of the protein phosphatase 1 (I-1) in cellular and animal models. I-1 acts as a nodal point between adrenergic and putatively non-adrenergic cardiac signaling pathways and is able to influence widespread cellular functions of protein phosphatase 1 which are contributing to cardiac health and disease, e.g. Ca²⁺ handling, sarcomere contractility and glucose metabolism. Finally, nearly all of these studies agree that I-1 is a promising drug target on the one hand but the outcome of its pharmacological regulation maybe extremely context-dependent on the other hand, thus warranting for careful interpretation of past and future experimental results. In this respect we will: 1) comprehensively review the current knowledge about structural, functional and regulatory properties of I-1 within the heart 2) highlight current working hypothesis and potential I-1 mediated disease mechanisms 3) discuss state-of-the-art knowledge and future prospects of a potential therapeutic strategy targeting I-1 by restoring the balance of cardiac protein phosphorylation.

Leg Lift Valsalva Maneuver for Treatment of Supraventricular Tachycardias

Clinical question Can conversion to sinus rhythm for a supraventricular tachycardia be enhanced by a postural modification to the Valsalva maneuver? Article chosen Appelboam A, Reuben A, Mann C, et al. Postural modification of the standard Valsalva manoeuvre for emergency treatment of supraventricular tachycardias (REVERT): a randomised controlled trial. Lancet 2015;386(10005):1747-53. 1 OBJECTIVE: To determine effectiveness of a postural modification of the Valsalva involving leg elevation and supine positioning.

Impact on a Person’s Daily Life During Episodes of Supraventricular Tachycardia

Purpose: To describe the impact of episodes of supraventricular tachycardia (SVT) on a person’s daily life from a holistic perspective. Method: A deductive descriptive design was used. Twenty semistructured interviews (12 women and 8 men) were conducted before planned ablation of SVT and were analyzed using qualitative content analysis. Results: Living with SVT had a complex impact on daily life. Initially, the patients described an inhibited existence due to demands to give up things that they had previously been doing, in case the unpredictable episodes of SVT would occur. The episodes caused fatigue and worry, which together created a barrier for living life to the full by making the person give up undertakings. The patients constantly needed to find short-term and long-term strategies to prevent new episodes from happening. Conclusion: Episodes of SVT entail a complex life situation as the person’s entire existence is affected in daily life. To understand the impact of SVT on daily life, nurses and other health care professionals need increased knowledge and understanding to be able to provide support through relevant information and take optimal care measures.

[Ablation of supraventricular tachycardias : Complications and emergencies]

Catheter ablation is an established treatment of supraventricular tachycardias (SVT) with high success rates of > 95 %. Complication rates range from 3 to 5 %, with serious complications occurring in about 0.8 %. There are general complications caused either by the vascular access or the catheters (e. g. hematomas, hemo-pneumothorax, embolism, thrombosis and aspiration) und specific ablation related complications (e. g. AV block during ablation of the slow pathway). The complication risk is elevated in elderly and multimorbid patients. Furthermore, the experience of the treating physician and the respective team plays an essential role. The purpose of this article is to give an overview on incidences, causes and management as well as prevention strategies of complications associated with catheter ablation of SVT.

Deceleration and Acceleration Capacities in Risk Stratification for Arrhythmias in Patients With Chronic Obstructive Pulmonary Disease

BACKGROUND

Patients with chronic obstructive pulmonary disease (COPD) have an increased risk for both supraventricular and ventricular arrhythmias. Autonomic dysregulation may be responsible for the development of arrhythmias in these patients, and its analysis could be useful for identifying those at high risk for arrhythmias.

STUDY QUESTION

Our purpose is to analyze the role of acceleration capacity (AC) and deceleration capacity (DC), novel markers of the autonomic balance, as potential arrhythmic risk predictors in patients with COPD.

STUDY DESIGN

We prospectively included 47 patients diagnosed with COPD, and a control group of 64 age-matched subjects without COPD. AC and DC values were obtained using 24-hour Holter monitoring. The arrhythmias were isolated premature atrial complexes, supraventricular tachycardias, isolated premature ventricular beats (PVC), and combined ventricular arrhythmias consisting in ventricular tachycardias or more than 10 PVC per hour.

RESULTS

Supraventricular arrhythmias and isolated PVC were more frequent in the COPD group. The DC was significantly lower (3.10 vs. 5.60, P < 0.0001) and AC higher (-4.60 vs. -6.60, P = 0.002) in patients with COPD. DC was identified as a predictor of arrhythmic events with an area under the curve (AUC) for premature atrial complexes >70/d of 0.72 (0.56-0.87, P = 0.013), for supraventricular tachycardias 0.76 (0.62-0.90, P = 0.002), and for combined ventricular arrhythmias 0.69 (0.54-0.82, P = 0.025). AC was predictor only for combined ventricular arrhythmias with an AUC of 0.74 (0.58-0.85, P = 0.002).

CONCLUSIONS

Patients with COPD associate a significant autonomic imbalance and a higher incidence of arrhythmias. DC could be a strong predictor for supraventricular and ventricular arrhythmias in patients with COPD with no clinically apparent cardiac disease. AC could be useful alongside with DC regarding the risk for ventricular arrhythmias, but seems to have lesser value as a predictor for supraventricular arrhythmias.

Age-related location of manifest accessory pathway and clinical consequences

BACKGROUND

Accessory pathway (AP) ablation is not always easy. Our purpose was to assess the age-related prevalence of AP location, electrophysiological and prognostic data according to this location.

METHODS

Electrophysiologic study (EPS) was performed in 994 patients for a pre-excitation syndrome. AP location was determined on a 12 lead ECG during atrial pacing at maximal preexcitation and confirmed at intracardiac EPS in 494 patients.

RESULTS

AP location was classified as anteroseptal (AS)(96), right lateral (RL)(54), posteroseptal (PS)(459), left lateral (LL)(363), nodoventricular (NV)(22). Patients with ASAP or RLAP were younger than patients with another AP location. Poorly-tolerated arrhythmias were more frequent in patients with LLAP than in other patients (0.009 for ASAP, 0.0037 for RLAP, <0.0001 for PSAP). Maximal rate conducted over AP was significantly slower in patients with ASAP and RLAP than in other patients. Malignant forms at EPS were more frequent in patients with LLAP than in patients with ASAP (0.002) or PSAP (0.001). Similar data were noted when AP location was confirmed at intracardiac EPS. Among untreated patients, poorly-tolerated arrhythmia occurred in patients with LLAP (3) or PSAP (6). Failures of ablation were more frequent for AS or RL AP than for LL or PS AP.

CONCLUSIONS

AS and RLAP location in pre-excitation syndrome was more frequent in young patients. Maximal rate conducted over AP was lower than in other locations. Absence of poorly-tolerated arrhythmias during follow-up and higher risk of ablation failure should be taken into account for indications of AP ablation in children with few symptoms.

An uncommon case of spontaneous conversion from AV re-entry tachycardia to AV nodal re-entry tachycardia in a patient with dual tachycardia

We report the case of a 46-year old patient in whom an electrophysiology study (EP) was performed due to paroxysmal supraventricular tachycardia documented in 12-lead ECG. During the EP study, supraventricular tachycardia was induced easily and it corresponded to orthodromic AV reentry tachycardia (AVRT) using a concealed left free wall accessory pathway. However, during the study AVRT spontaneously and repeatedly converted to the typical slow-fast AV node reentry tachycardia (AVNRT). Both accessory and AV nodal slow pathways were ablated, due to the finding that both AVRT and AVNRT were independently inducible during the EP study.

Risk Stratification for Arrhythmic Events in Patients With Asymptomatic Pre-Excitation: A Systematic Review for the 2015 ACC/AHA/HRS Guideline for the Management of Adult Patients With Supraventricular Tachycardia

Objective—

To review the literature systematically to determine whether noninvasive or invasive risk stratification, such as with an electrophysiological study of patients with asymptomatic pre-excitation, reduces the risk of arrhythmic events and improves patient outcomes.

Methods—

PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials (all January 1, 1970, through August 31, 2014) were searched for randomized controlled trials and cohort studies examining noninvasive or invasive risk stratification in patients with asymptomatic pre-excitation. Studies were rejected for low-quality design or the lack of an outcome, population, intervention, or comparator of interest or if they were written in a language other than English.

Results—

Of 778 citations found, 9 studies met all the eligibility criteria and were included in this paper. Of the 9 studies, 1 had a dual design—a randomized controlled trial of ablation versus no ablation in 76 patients and an uncontrolled prospective cohort of 148 additional patients—and 8 were uncontrolled prospective cohort studies (n=1594). In studies reporting a mean age, the range was 32 to 50 years, and in studies reporting a median age, the range was 19 to 36 years. The majority of patients were male (range, 50% to 74%), and <10% had structural heart disease. In the randomized controlled trial component of the dual-design study, the 5-year Kaplan-Meier estimates of the incidence of arrhythmic events were 7% among patients who underwent ablation and 77% among patients who did not undergo ablation (relative risk reduction: 0.08; 95% confidence interval: 0.02 to 0.33; P <0.001). In the observational cohorts of asymptomatic patients who did not undergo catheter ablation (n=883, with follow-up ranging from 8 to 96 months), regular supraventricular tachycardia or benign atrial fibrillation (shortest RR interval >250 ms) developed in 0% to 16%, malignant atrial fibrillation (shortest RR interval ≤250 ms) in 0% to 9%, and ventricular fibrillation in 0% to 2%, most of whom were children in the last case.

Conclusions—

The existing evidence suggests risk stratification with an electrophysiological study of patients with asymptomatic pre-excitation may be beneficial, along with consideration of accessory-pathway ablation in those deemed to be at high risk of future arrhythmias. Given the limitations of the existing data, well-designed and well-conducted studies are needed.

Taquicardias supraventriculares. Estado del arte

<p>Las taquicardias supraventriculares son un grupo de entidades clínicas prevalentes en la población general, pero que afectan con mayor frecuencia a la población adulta; son ritmos rápidos y generalmente regulares en los cuales se encuentra implicada alguna estructura por encima de la bifurcación del haz de His para formación o perpetuación. El diagnóstico de estas entidades requiere un abordaje clínico sistemático, siendo el electrocardiograma de superficie la principal herramienta para su adecuada clasificación. El tratamiento de las taquicardias supraventriculares dependerá del estado hemodinámico del paciente, el cual definirá el requerimiento de terapia eléctrica o tratamiento médico. Se debe hacer una selección adecuada de los pacientes que requieren estudio electrofisiológico y ablación.</p>

[Cardiac arrhythmias: Diagnosis and management]

Cardiac arrhythmias, with, on top of the list, atrial fibrillation, are frequent conditions and any physician might have to get involved at any stage of patient care (from diagnosis to treatment), without always having the opportunity to immediately refer to the cardiologist. The aim of this review is to present a summary of pathophysiology, clinical and electrocardiographic presentations, as well as diagnostic and therapeutic strategies for the main cardiac arrhythmias. Supra-ventricular tachycardias (atrial fibrillation and flutter, atrioventricular reciprocating tachycardias) and ventricular tachycardias will be consecutively presented and discussed.

[Typical atrial flutter: Diagnosis and therapy]

Typical, cavotricuspid-dependent atrial flutter is the most common atrial macroreentry tachycardia. The incidence of atrial flutter (typical and atypical forms) is age-dependent with 5/100,000 in patients less than 50 years and approximately 600/100,000 in subjects > 80 years of age. Concomitant heart failure or pulmonary disease further increases the risk of typical atrial flutter.Patients with atrial flutter may present with symptoms of palpitations, reduced exercise capacity, chest pain, or dyspnea. The risk of thromboembolism is probably similar to atrial fibrillation; therefore, the same antithrombotic prophylaxis is required in atrial flutter patients. Acutely symptomatic cases may be subjected to cardioversion or pharmacologic rate control to relieve symptoms. Catheter ablation of the cavotricuspid isthmus represents the primary choice in long-term therapy, associated with high procedural success (> 97 %) and low complication rates (0.5 %).This article represents the third part of a manuscript series designed to improve professional education in the field of cardiac electrophysiology. Mechanistic and clinical characteristics as well as management of isthmus-dependent atrial flutter are described in detail. Electrophysiological findings and catheter ablation of the arrhythmia are highlighted.

Outcomes in Women Undergoing Electrophysiological Procedures

The number of invasive electrophysiological procedures is steadily increasing in Western countries, as the age of the population increases and technologies advance. In recent years, gender-related differences in cardiac rhythm disorders have been increasingly appreciated, which can potentially have a great impact on the outcomes of invasive electrophysiological procedures. Among supraventricular arrhythmias, women have a higher incidence of atrioventricular nodal re-entrant tachycardia and a significantly lower incidence of atrioventricular re-entrant tachycardia compared with males, and present to ablation procedures later and after having failed more antiarrhythmic drugs. The results of catheter ablation of atrial fibrillation in women have been reported worse than in men. This finding is possibly due to a later referral of females to ablation procedures, who present older and with a higher incidence of long-standing persistent atrial fibrillation. With regard to cardiac device implantation procedures, a smaller survival benefit from prophylactic implantable cardioverter defibrillator (ICD) implantation has been shown in women, essentially due to gender-specific differences in the clinical course of patients with severe left ventricular dysfunction, with women dying predominantly from non-arrhythmic causes. On the other side, the clinical outcome of cardiac resynchronisation therapy seems to be more favourable in women, who experience a greater degree of reverse left ventricular remodelling and a striking decrease of heart failure events or mortality after biventricular pacing. This review will summarise the available evidence on gender-related differences in outcomes of invasive electrophysiological procedures.