Ongoing substrate-driven atrial fibrillation "boxed" in the left atrial posterior wall with ablation: a case report

Patients undergoing valve surgery for rheumatic heart disease are expected to develop significant atrial arrhythmogenic substrates outside of the pulmonary veins, which sometimes require complex ablation techniques for the treatment of symptomatic arrhythmias. We describe, herein, the case of a 76-year-old male undergoing endocardial ablation for the treatment of symptomatic persistent atrial fibrillation which developed after aortic and mitral valve replacement with a simultaneous tricuspid ring annuloplasty. Following pulmonary vein isolation, the patient's atrial fibrillation was converted into cavotricuspid isthmus-dependent atrial flutter. After a successful cavotricuspid isthmus ablation, the arrhythmia reverted back to a left atrial tachyarrhythmia originating from the posterior wall. A linear left atrial lesion led to the electrical isolation of a large area, which included the posterior wall, as well as the containment of the ongoing fibrillatory activity, while sinus rhythm was restored in the rest of the atria. In conclusion, successful left atrial posterior wall isolation can be achieved in the setting of severe scarring due to previous atriotomy by creating a linear lesion on the atrial roof, in conjunction with pulmonary vein isolation, sparing the patient from requiring bottom-line ablation, and avoiding possible esophageal injury. Such compartmentalization of the left atrium may effectively contain local fibrillatory activity, while allowing for the restoration of sinus rhythm.

Endocardial, epicardial, and right atrial approach for catheter ablation of premature ventricular contractions from the inferoseptal process of the left ventricle

BACKGROUND

Inferoseptal process of the left ventricle (ISP-LV) might be a source of idiopathic ventricular arrhythmias. In these cases, ectopic foci are accessible from the LV endocardium, epicardially from the middle cardiac vein as well as from the right atrium (RA). This study reports a series of patients with premature ventricular contractions (PVCs) arising from the ISP-LV that were successfully ablated following access from different structures.

METHODS AND RESULTS

Five patients (4 males, age 61 ± 12.8 years) with PVCs arising from the ISP-LV were successfully ablated using three different approaches for ablation-endocardial, epicardial (through coronary sinus or its branches), and RA approaches. Endocardial LV mapping, RA, and coronary sinus (CS) mapping were performed in all five cases. PVCs demonstrated RBBB or LBBB-like morphology and left superior axis. The three patients ablated endocardially had a maximum deflection index (MDI) of 0.36, 0.43, and 0.54, whereas in the remaining 2 patients, MDI was 0.57 and both demonstrated QS morphology in the inferior leads. Local activation time at the successful ablation site was 35 ± 8.9 (26-55) msec pre-QRS. Pacemapping at the successful ablation site resulted in a good (11/12) or perfect (12/12) QRS match in all cases. Three of the patients demonstrated frequent monomorphic PVCs of another morphology suggesting a remote exit site. All patients remained arrhythmia-free after a mean follow-up of 21 ± 15 (6-36) months.

CONCLUSION

Successful ablation of PVCs from ISP-LV may require access from the CS or even RA apart from LV endocardial approach. Not infrequently patients demonstrate additional PVC foci.

Epidemiology and impact of frailty in patients with atrial fibrillation in Europe

BACKGROUND

Frailty is a medical syndrome characterised by reduced physiological reserve and increased vulnerability to stressors. Data regarding the relationship between frailty and atrial fibrillation (AF) are still inconsistent.

OBJECTIVES

We aim to perform a comprehensive evaluation of frailty in a large European cohort of AF patients.

METHODS

A 40-item frailty index (FI) was built according to the accumulation of deficits model in the AF patients enrolled in the ESC-EHRA EORP-AF General Long-Term Registry. Association of baseline characteristics, clinical management, quality of life, healthcare resources use and risk of outcomes with frailty was examined.

RESULTS

Among 10,177 patients [mean age (standard deviation) 69.0 (11.4) years, 4,103 (40.3%) females], 6,066 (59.6%) were pre-frail and 2,172 (21.3%) were frail, whereas only 1,939 (19.1%) were considered robust. Baseline thromboembolic and bleeding risks were independently associated with increasing FI. Frail patients with AF were less likely to be treated with oral anticoagulants (OACs) (odds ratio 0.70, 95% confidence interval 0.55-0.89), especially with non-vitamin K antagonist OACs and managed with a rhythm control strategy, compared with robust patients. Increasing frailty was associated with a higher risk for all outcomes examined, with a non-linear exponential relationship. The use of OAC was associated with a lower risk of outcomes, except in patients with very/extremely high frailty.

CONCLUSIONS

In this large cohort of AF patients, there was a high burden of frailty, influencing clinical management and risk of adverse outcomes. The clinical benefit of OAC is maintained in patients with high frailty, but not in very high/extremely frail ones.

Contrast-induced neurotoxicity presented as transient cortical blindness after stent-assisted coiling of a medium-sized unruptured basilar artery aneurysm: A case report and review of the literature

Background:

Contrast-induced neurotoxicity is a rare event after endovascular diagnostic procedures or interventions and presents as transient neurological deficit. Herewith, we present a case of reversible complete cortical blindness after uneventful stent-assisted coiling of a medium-sized unruptured basilar artery aneurysm.

Case Description:

A 70-year-old woman with a medium-sized 10 mm/6 mm wide neck basilar tip aneurysm was planned for endovascular obliteration of the lesion. The procedure was done under general anesthesia. The contrast agent was iso-osmolar, nonionic. The aneurysm was coiled, and a stent was placed in the left posterior cerebral artery achieving sufficient aneurysm packing. No signs of vessel obliteration were observed during the procedure. On awakening of anesthesia, the patient reported complete visual loss. Ophthalmological examination was normal. The patient was brought back to the angio-suite but there were no signs of parent vessel compromise from the endovascular implants or distal vessel occlusion. An MRI of the brain was done showing no signs of brain ischemia, just mild brain edema in both occipital lobes. Given the results of the radiological studies and clinical presentation, the diagnosis of contrast-induced neurotoxicity was accepted. In 72 h, the patient had complete resolution of the visual loss and was discharged home with no additional neurological worsening.

Conclusion:

Contrast-induced neurotoxicity is a rare event that can occur after uneventful endovascular interventions of the brain vessels. Knowledge of this rare complication, after exclusion of all other possible reversible causes, is important for the treatment and prognosis of the patient.

Age and impaired left atrial performance are associated with increased atrial fibrosis in patients with paroxysmal and persistent atrial fibrillation

Background

Atrial performance assessed by strain imaging is used as a surrogate for left atrial (LA) structural remodelling. Presence of low voltage zones (LVZs) detected by three-dimensional electroanatomical mapping in patients with atrial fibrillation (AF) denotes more expressed extrapulmonary substrate potentially leading to worse outcomes following pulmonary vein isolation (PVI) for the treatment of AF.

Purpose

The current study aims to investigate the association between strain imaging parameters from echocardiography and the presence and extent of LVZs derived from LA electroanatomical mapping in patients undergoing AF ablation.

Methods

Seventy-eight patients (58 males, 74%) aged 59±9.48 years undergoing PVI for paroxysmal (35 patients, 49%) or persistent AF were prospectively studied. Preprocedural echocardiography included LA strain imaging assessing global LA strain (LAS) and regional strain of the basolateral region (RSLB). During the procedure, LA electroanatomical mapping during paced atrial rhythm was performed in all patients obtaining a LA voltage map. All LA maps were analysed offline using a custom-made software calculating the zone of low bipolar voltage <0.5 mV (LVZ<0.5mV) and the total LA endocardial area excluding pulmonary veins antra. LVZ<0.5mv was expressed as an absolute value and as percentage of the whole LA area.

Results

Patients aged more than 65 years (N=21, 27%) demonstrated a larger area of LVZ<0.5mV: 25.5±17.8 cm2 vs. 9.4±10.6 cm2 in those younger than 65 years, P=0.001. This corresponded to a higher proportion of the LA area demonstrating LVZ<0.5mV in patients older than 65 years: 22.6±14.6% vs. 8.9±11.8% in those younger than 65 years, P<0.0001. Twenty-nine of 78 patients (37.1%) had preprocedural LAS<20% and 23 (29.5%) demonstrated RSLB of <21%. Patients with LAS <20% had a higher total LVZ<0.5mV: 20.3±16.6 cm2 vs. 9.8±12.1 cm2 in patients with LAS≥20% at baseline, P=0.004. This equaled to 17.7±15.6% vs. 9.5±11.9% of total LA area, respectively (P=0.011). Patients with RSLB<21% also demonstrated larger areas of LVZ<0.5mV in the LA: 21.6±17.9 cm2 vs. 10.39±11.83 cm2 in the patients with RSLB ≥21%, P=0.012. Expressed as a proportion of the whole LA area the difference remained significant: 18.8±17.1% vs. 9.9±11.6%, respectively P=0.01.

Conclusion

Older age and impaired LA performance assessed by LA strain imaging are associated with larger areas of LVZ<0.5mV possibly reflecting more expressed LA fibrotic changes in patients with paroxysmal and persistent AF. These findings might serve in the preprocedural selection of the patients undergoing catheter ablation of AF.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): Bulgarian Society of Cardiology

General anaesthesia during radiofrequency ablation of atrial fibrillation is associated with improved procedural characteristics but with similar long-term outcomes: a single center study

Funding Acknowledgements

Type of funding sources: None.

Introduction

General anaesthesia (GA) or conscious sedation can be used during radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) based on physician’s and patient’s preference. Increasing number of centers include GA in their institutional protocols for RFCA of AF. 

Purpose

The current study aims to compare real-world data on procedural characteristics, complication rate and procedural outcomes in patients undergoing RFCA of AF under GA or sedation at a single center.

Methods

A total of 167 patients (116 males, age 57.53 ± 9.78 years) with paroxysmal or persistent AF undergoing RFCA were studied retrospectively. Patients underwent RFCA under GA (108 patients, Group 1) provided by the anaesthesia team at our institution or under conscious sedation (59 patients, Group 2) guided by the operator using bolus doses of midazolam and fentanyl. We compared procedural time, fluoroscopy time, dose-area product (DAP), number of lesions and cumulative RF time between the two groups. We also analysed the complication rates and the long-term outcome in the two groups. Results are presented as mean ± SD or median (25th – 75th percentile).

Results

  Groups 1 and 2 were comparable in terms of baseline clinical characteristics. Group 1 patients demonstrated significantly shorter procedural time as compared to Group 2: 149.52 ± 41.31 min vs. 208.23 ± 77.10 min, P < 0.0005. Fluoroscopy time was also shorter in Group 1 24 (20-31.75) min compared to 36 (22.5-46.5) min in Group 2, P < 0.0001. This corresponded to lower radiation dose expressed by DAP which was also significantly lower in Group 1 patients: 3230 (1660-6793.2) cGy/cm2 vs. 13880 (4215-21324) cGy/cm2 for Group 2, P < 0.0001. Administration of GA during the procedure was associated with lower number of RF applications: 52.49 ± 19.36 in Group 1 vs. 68.33 ± 30.74 in Group 2, P = 0.0001. This corresponded with the lower cumulative RF time noted in the patients from Group 1: 2499.2 ± 824.17 sec vs. 3220 ± 1357.26 sec in Group 2, P < 0.0001. Procedural complications occurred in 5 patients from Group 1 (4.6%) and in 8 patients (13.6%) in Group 2, P = 0.066. There was a single case of atrioesophageal fistula in a patient from Group 1. After a median follow-up of 20 (8-41) months 75% of the patients from both Group 1 and Group 2 were arrhythmia-free following 1.5 ± 0.68 procedures (P = 1.0). 

Conclusion

Performing RFCA of AF under GA is associated with shorter procedural time, lower radiation dose and with the need for less energy application. This does not result in significantly lower complication rates. Long-term procedural outcomes do not seem to be affected by the use of GA.

Antiplatelet therapy after PCI in patients with high risk of bleeding

The progress of percutaneous coronary interventions (PCI) over the last few decades facilitated treatment of increasingly complex patient populations. The introduction of drug-eluting stents (DESs) led to need of stronger and prolonged inhibition of platelets which in turn increased the incidence of bleeding complications. The identification and management of patients at high bleeding risk (HBR) during and after percutaneous coronary interventions (PCI) is still problematic in everyday clinical practice.

P219 The role of color-coded duplex sonography in evaluating coronary-subclavian steal syndrome

Background

Coronary-subclavian steal syndrome is a rare phenomenon leading to dysfunction of left internal mammary artery (LIMA)-graft after coronary artery grafting with the occurrence of proximal stenosis of the left subclavian artery (LSA), which causes myocardial ischemia due to a blood-steal phenomenon through a fully patent LIMA-graft.

Purpose

To evaluate the role of color-coded duplex sonography (CCDS) in follow-up of all symptomatic patients with LIMA-graft after aorto-coronary bypass grafting (ACBG).

Methods

Two men and one woman with recurrence of angina pectoris symptoms and vertigo after ACBG with LIMA-LAD graft. Patients were hospitalized in cardiology for coronary graft assessment via selective coronary arteriography. Due to the discovery of fully patent grafts with a combination of varying degrees of proximal stenosis of the LSA, CCDS with a high-frequency linear probe was used to evaluate cervical arteries, LSA and the LIMA-graft flow rate applying functional probe for hyperemia (PH) of the left upper limb for hemodynamic assessment of significance of the steal syndrome.

Results

One woman at age 72 after ACBG – LIMA-LAD; RM1; RCA -s.v.g. Selective coronary arteriography showed patent bypass grafts with 70% proximal stenosis of LSA. The performed CCDS showed a LIMA-graft blood flow reduction from 36 ml/min to 12 ml/min in a sample for left upper limb hyperemia. There was a difference in the blood pressure of the upper limbs within 20 mmHg. Dobutamine stress echocardiography was performed, confirming ischemic zones in the LAD- peak segments.

A 63 year old man after ACBG x 4 with a difference in blood pressure of upper limbs within 40 mmHg. The performed CCDS showed thrombosis of the left internal carotid artery, high-grade stenosis of the right internal carotid artery, high-grade stenosis of LSA, alternating blood flow in the left vertebral artery – a sign of hemodynamically significant steal syndrome.

A 65 year old male after ACBG x 3 (LIMA-LAD, RCA, OM1 -s.v.g.). The selective coronary arteriography showed patent LIMA-graft with 50% proximal stenosis of LSA with a trans-stenotic pressure gradient of 20 mmHg. To identify the steal phenomenon we used CCDS, which showed a blood flow reduction into the LIMA-graft from 14.2 ml/min to 7.5 ml/ min - data of hemodynamically significant steal syndrome.

Patients were treated with percutaneous transluminal angioplasty and stenting of the LSA with postprocedure reduction of angina pectoris complaints, no difference in the blood pressure of upper limbs and no reduction of LIMA-graft blood flow during the probe for hyperemia of the upper limb.

Conclusion(s) Color-coded duplex sonography is an important and indispensable technique, part of the overall assessment of hemodynamics in case of coronary-subclavian steal syndrome and probably may prove to be a first method of choice in follow-up of all symptomatic patients with LIMA-LAD graft.

Impact of chronic obstructive pulmonary disease and dyspnoea on clinical outcomes in ticagrelor treated patients undergoing percutaneous coronary intervention in the randomized GLOBAL LEADERS trial

Aims

To evaluate long-term safety and efficacy of ticagrelor monotherapy in patients undergoing percutaneous coronary interventions (PCIs) in relation to chronic obstructive pulmonary disease (COPD) at baseline and the occurrence of dyspnoea reported as adverse event (AE) that may lead to treatment non-adherence.

Methods and results

This is a non-prespecified, post hoc analysis of the randomized GLOBAL LEADERS trial (n = 15 991), comparing the experimental strategy of 23-month ticagrelor monotherapy following 1-month dual antiplatelet therapy (DAPT) after PCI with the reference strategy of 12-month DAPT followed by 12-month aspirin monotherapy. Impact of COPD and dyspnoea AE (as a time-dependent covariate) on clinical outcomes was evaluated up to 2 years. The primary endpoint was a 2-year all-cause mortality or non-fatal, centrally adjudicated, new Q-wave myocardial infarction. The presence of COPD (n = 832) was the strongest clinical predictor of 2-year all-cause mortality after PCI [hazard ratio (HR) 2.84; 95% confidence interval (CI) 2.21–3.66; P adjusted = 0.001] in this cohort (n = 15 991). No differential treatment effects on 2-year clinical outcomes were found in patients with and without COPD (primary endpoint: HR 0.88; 95% CI 0.58–1.35; P = 0.562; P int = 0.952). Overall, at 2 years dyspnoea was reported as an AE in 2101 patients, more frequently among COPD patients, irrespective of treatment allocation (27.2% in experimental arm vs. 14.5% in reference arm, P = 0.001). Its occurrence was not associated with a higher rate of the primary endpoint (P adjusted = 0.640) in the experimental vs. the reference arm.

Conclusion

In this exploratory analysis, COPD negatively impacted long-term prognosis after PCI. Despite higher incidence of dyspnoea in the experimental arm, in particular among COPD patients, the safety of the experimental treatment strategy appeared not to be affected.

Clinical trial registration unique identifier

NCT01813435.

Catheter ablation of typical atrial flutter with the superior approach in a patient with inferior vena cava interruption

Inferior vena cava (IVC) interruption is a rare condition that might pose difficulties during typical flutter ablation. When azygos vein continuation is present ablation via the femoral route could be performed. In the absence of azygos vein continuation, typical atrial flutter ablation via a superior approach from the SVC is feasible.

Successful selective arterial thrombolysis in patient with acute abdominal thromboembolism

The paper reports successful thrombolysis conducted in 64 years old woman admitted to the clinic with clinical and angiographic data for acute surgical abdomen caused by acute tromboembolia of arteria mesenterica superior (AMS). The therapeutic approach required to undertake lifesaving decision on i.e. surgical vs. invasive treatment in conditions of emergency. Finally, it was decided to undertake invasive treatment with successful restoration of blood flow in the related artery. The patient was discharged from the clinic with considerable clinical improvement on the fifth day of her stay. The case report includes discussion on issues relating the consequence of the diagnostic and interventional procedures in such patients, opportunities for conducting emergency thrombolysis in acute embolia of AMS and preventive measures in patients with high tromboembolic risk.

Initiating sacubitril/valsartan (LCZ696) in heart failure: results of TITRATION, a double-blind, randomized comparison of two uptitration regimens

Aims

To assess the tolerability of initiating/uptitrating sacubitril/valsartan (LCZ696) from 50 to 200 mg twice daily (target dose) over 3 and 6 weeks in heart failure (HF) patients (ejection fraction ≤35%).

Methods and results

A 5‐day open‐label run‐in (sacubitril/valsartan 50 mg twice daily) preceded an 11‐week, double‐blind, randomization period [100 mg twice daily for 2 weeks followed by 200 mg twice daily (‘condensed’ regimen) vs. 50 mg twice daily for 2 weeks, 100 mg twice daily for 3 weeks, followed by 200 mg twice daily (‘conservative’ regimen)]. Patients were stratified by pre‐study dose of angiotensin‐converting enzyme inhibitor/angiotensin‐receptor blocker (ACEI/ARB; low‐dose stratum included ACEI/ARB‐naïve patients). Of 540 patients entering run‐in, 498 (92%) were randomized and 429 (86.1% of randomized) completed the study. Pre‐defined tolerability criteria were hypotension, renal dysfunction and hyperkalaemia; and adjudicated angioedema, which occurred in (‘condensed’ vs. ‘conservative’) 9.7% vs. 8.4% (P = 0.570), 7.3% vs. 7.6% (P = 0.990), 7.7% vs. 4.4% (P = 0.114), and 0.0% vs. 0.8% of patients, respectively. Corresponding proportions for pre‐defined systolic blood pressure <95 mmHg, serum potassium >5.5 mmol/L, and serum creatinine >3.0 mg/dL were 8.9% vs. 5.2% (P = 0.102), 7.3% vs. 4.0% (P = 0.097), and 0.4% vs. 0%, respectively. In total, 378 (76%) patients achieved and maintained sacubitril/valsartan 200 mg twice daily without dose interruption/down‐titration over 12 weeks (77.8% vs. 84.3% for ‘condensed’ vs. ‘conservative’; P = 0.078). Rates by ACEI/ARB pre‐study dose stratification were 82.6% vs. 83.8% (P = 0.783) for high‐dose/‘condensed’ vs. high‐dose/‘conservative’ and 84.9% vs. 73.6% (P = 0.030) for low‐dose/‘conservative’ vs. low‐dose/‘condensed’.

Conclusions

Initiation/uptitration of sacubitril/valsartan from 50 to 200 mg twice daily over 3 or 6 weeks had a tolerability profile in line with other HF treatments. More gradual initiation/uptitration maximized attainment of target dose in the low‐dose ACEI/ARB group.

DNA Breathing Dynamics in the Presence of a Terahertz Field

We consider the influence of a terahertz field on the breathing dynamics of double-stranded DNA. We model the spontaneous formation of spatially localized openings of a damped and driven DNA chain, and find that linear instabilities lead to dynamic dimerization, while true local strand separations require a threshold amplitude mechanism. Based on our results we argue that a specific terahertz radiation exposure may significantly affect the natural dynamics of DNA, and thereby influence intricate molecular processes involved in gene expression and DNA replication.