Coronary sinus signal amplitude predicts left atrial scarring

BACKGROUND

Left atrial scarring is recognised as a critical component in the maintenance of atrial fibrillation and is associated with the failure of interventional treatment. Diminished bipolar voltage (LV) has been proposed as a useful tool for left atrial scar quantification. We hypothesised that, due to its anatomic location, signals on the coronary sinus catheter might be used to predict the amount of left atrial low voltage.

METHODS AND RESULTS

A total of 124 patients (42% women, average age 66 ± 9 years) were included. Forty-one with paroxysmal and 83 with persistent atrial fibrillation. Left atrial low-voltage (<0.5 mV, measured during sinus rhythm) area size and distribution varied considerably among the included patients (mean: 34.9%; maximum: 94.6%; minimum: 0.4%). Spearman correlation revealed a strong negative correlation between bipolar voltage of the signals on the coronary sinus catheter and the amount of left atrial scarring (R = -0.778, p < .0001). The optimal CS voltage cut off for prediction of left atrial low-voltage size of ≥50% was 1.9 mV with an area-under-the receiver-operating-characteristic (ROC) curve of 0.982, a sensitivity of 97% and a specificity of 98%.

CONCLUSIONS

There is a strong negative correlation between the size of left atrial low-voltage areas (LVA) and coronary sinus signal amplitude. With increasing left atrial LVA size, CS signal amplitudes decrease, and vice versa. On the basis of these findings, average CS signal amplitudes of ≤1.9 mV can be used as a predictor for a left atrial low-voltage size of ≥50%.

Marathon running increases circulating endothelial- and thrombocyte-derived microparticles

Background Acute vascular effects of high intensity physical activity are incompletely characterized. Circulating microparticles are cellular markers for vascular activation and damage. Methods Microparticles were analysed in 99 marathon runners (49 ± 6 years, 22% female) of the prospective Berlin Beat of Running study. Blood samples were taken within three days before, immediately after and within two days after the marathon run. Endothelial-derived microparticles were labelled with CD144, CD31 and CD62E, platelet-derived microparticles with CD62P and CD42b, leukocyte-derived microparticles with CD45 and monocyte-derived microparticles with CD14. Results Marathon running induced leukocytosis (5.9 ± 0.1 to 14.8 ± 0.3 10⁹/l, p < 0.0001) and increased platelet counts (239 ± 4.6 to 281 ± 5.9 10⁹/l, p < 0.0001) immediately after the marathon. Blood monocytes increased and lymphocytes decreased after the run ( p < 0.0001). Endothelial-derived microparticles were acutely increased ( p = 0.008) due to a 23% increase of apoptotic endothelial-derived microparticles ( p = 0.007) and returned to baseline within two days after the marathon. Thrombocyte-derived microparticles acutely increased by 38% accompanied by an increase in activated and apoptotic thrombocyte-derived microparticles ( p ≤ 0.0001) each. Both monocyte- and leukocyte-derived microparticles were decreased immediately after marathon run ( p < 0.0001) and remained below baseline until day 2. Troponin T increased from 12 to 32 ng/l ( p < 0.0001) immediately after the run and returned to baseline after two days. Conclusion Circulating apoptotic endothelial- and thrombocyte-derived microparticles increased after marathon running consistent with an acute pro-thrombotic and pro-inflammatory state. Exercise-induced vascular damage reflected by microparticles could indicate potential mechanisms of post-exertional cardiovascular complications. Further studies are warranted to investigate microparticles as markers to identify individuals prone to such complications.

The effect of an ultra-low frame rate and antiscatter grid-less radiation protocol for cardiac device implantations

BACKGROUND AND AIMS

Antiscatter grids improve image contrast by absorbing scattered x-ray beams, although by removing the antiscatter grid patient dose can be reduced as more x-ray beams reach the image receptor. Additionally, there is a trend toward ultra-low frame rates for radiation dose reduction during various electrophysiology procedures. As for most cardiac device implantations (CIED) image quality demands are usually modest, the purpose of this study was to assess the safety and efficacy of an ultra-low frame rate and scatter grid-less radiation protocol.

METHODS/RESULTS

A total of 140 patients undergoing CIED implantation between 2014 and 2017 were included in the study. Seventy patients (50%) implanted after implementation of the antiscatter grid-less and ultra-low frame rate protocol were matched to controls before the dose-reduction protocol was established. Forty patients (28.6%) had a one-chamber pacemaker or one-chamber implantable cardioverter defibrillator (ICD) implantation/revision, 60 (42.9%) had a two-chamber pacemaker or two-chamber ICD implantation/revision, and 40 (28.6%) patients had a cardiac resynchronization therapy device implantation/revision. Removing the antiscatter-grid and lowering the frame rate led to a 73% reduction of the overall dose area product (1,206 ± 2,015 vs 324 ± 422 μGym, P < 0.001). Procedural duration (95 ± 51 minutes vs 82 ± 44 minutes, P  =  0.053) and rate of complications were not significantly different between the two groups.

CONCLUSION

The use of an ultra-low frame rate and antiscatter grid-less radiation protocol significantly reduced radiation dose for implantation of CIED and led to very low average patient doses, while procedural duration and complication rates did not increase.

Effects of propofol on ventricular repolarization and incidence of malignant arrhythmias in adults

BACKGROUND

Propofol is commonly used for procedural sedation in interventional electrophysiology. However, ventricular arrhythmias under Propofol have been reported. Our aim was to investigate ventricular repolarization and incidence of ventricular arrhythmias under Propofol infusion in adults with cardiac arrhythmias.

METHODS

QRS, QTcB (Bazett), QTcFri (Fridericia), JTc, measurement of T peak to Tend time (T_p-e) at baseline and under Propofol infusion was performed in 235 patients. Screening for unexpected ventricular arrhythmias was performed in 1165 patients undergoing EP procedures under Propofol.

RESULTS

A significant prolongation of T_p-e under Propofol infusion (79.7±17.3 vs. 86.4±22.5ms, p<0.001) and of QTcFri (429.3±35.8 vs. 435.5±36.5, p=0.033) was detected. No significant change of the QTcB interval, JTc interval or QRS duration was observed. One case (0.09%) of ventricular fibrillation during rapid ventricular pacing under Propofol occurred.

CONCLUSION

Although transmural dispersion of ventricular repolarisation is increased under Propofol, incidence of malignant ventricular arrhythmias is low. For evaluation of QT interval under Propofol, Fridericia's correction formula should be used rather than Bazett's formula.

Frequency of exercise-induced ST-T-segment deviations and cardiac arrhythmias in recreational endurance athletes during a marathon race: results of the prospective observational Berlin Beat of Running study

OBJECTIVES

While regular physical exercise has many health benefits, strenuous physical exercise may have a negative impact on cardiac function. The 'Berlin Beat of Running' study focused on feasibility and diagnostic value of continuous ECG monitoring in recreational endurance athletes during a marathon race. We hypothesised that cardiac arrhythmias and especially atrial fibrillation are frequently found in a cohort of recreational endurance athletes. The main secondary hypothesis was that pathological laboratory findings in these athletes are (in part) associated with cardiac arrhythmias.

DESIGN

Prospective observational cohort study including healthy volunteers.

SETTING AND PARTICIPANTS

One hundred and nine experienced marathon runners wore a portable ECG recorder during a marathon race in Berlin, Germany. Athletes underwent blood tests 2-3 days prior, directly after and 1-2 days after the race.

RESULTS

Overall, 108 athletes (median 48 years (IQR 45-53), 24% women) completed the marathon in 249±43 min. Blinded ECG analysis revealed abnormal findings during the marathon in 18 (16.8%) athletes. Ten (9.3%) athletes had at least one episode of non-sustained ventricular tachycardia, one of whom had atrial fibrillation; eight (7.5%) individuals showed transient ST-T-segment deviations. Abnormal ECG findings were associated with advanced age (OR 1.11 per year, 95% CI 1.01 to 1.23), while sex and cardiovascular risk profile had no impact. Directly after the race, high-sensitive troponin T was elevated in 18 (16.7%) athletes and associated with ST-T-segment deviation (OR 9.9, 95% CI 1.9 to 51.5), while age, sex and cardiovascular risk profile had no impact.

CONCLUSIONS

ECG monitoring during a marathon is feasible. Abnormal ECG findings were present in every sixth athlete. Exercise-induced transient ST-T-segment deviations were associated with elevated high-sensitive troponin T (hsTnT) values.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01428778; Results.

Safety and efficacy of applying a low-dose radiation fluoroscopy protocol in device implantations

Aims

For cardiac implantable electronic device (CIED) implantations, visualization of lead placement is necessary and fluoroscopy remains by far the most commonly used technique. With simple changes in the X-ray system settings, total radiation dose can be reduced significantly. The purpose of this study was to assess the safety and efficacy of various CIED implantations performed after implementation of a new dose reduction protocol (DRP).

Methods and results

We conducted a retrospective chart review of 584 patients undergoing CIED implantation or revision in our hospital. Of these patients, 280 (48%) underwent the implantation prior to and 304 (52%) after the DRP introduction. The DRP included various changes for optimized image processing and exposure system settings to enable dose reduction, as well as a reduced frame rates (4 FPS for fluoroscopy and 7.5 FPS for cinematographic images). Of the 584 patients, 53 (9.1%) had a one-chamber pacemaker, 232 (39.7%) a two-chamber pacemaker, 133 (22.8%) a one-chamber ICD, 35 (6.0%) a two-chamber ICD, 82 (14.0%) a CRT (de novo) implantation, and 49 (8.3%) had an upgrade to a CRT device. DRP was associated with a 64% reduction of the dose-area product (1372 ± 2659 vs. 3792 ± 5025 cGcm2, P < 0.001), while fluoroscopy duration (13 ± 15 vs. 13 ± 15 min) and procedural duration (93 ± 52 vs. 92 ± 52 min.) did not significantly increase. Complication rates did not differ significantly between the two groups.

Conclusion

The DRP proved to effectively reduce radiation dose for all types of CIED implantations. Fluoroscopy time, total procedure time, and the number of complications did not increase after introducing the DRP.

Does the extent of left atrial arrhythmogenic substrate depend on the electroanatomical mapping technique: impact of pulmonary vein mapping catheter vs. ablation catheter

Aims

In persistent atrial fibrillation (AF), left atrial low-voltage areas and complex fractionated atrial electrograms (CFAEs) have been thoroughly discussed as critical substrate points for AF perpetuation. Thus, in patients undergoing pulmonary vein isolation, these sites are often considered additional ablation targets. Currently, mapping techniques for these substrate indicators are still under discussion. The aim of this study was to evaluate the impact of different mapping catheters on the detection of low-voltage areas and CFAE.

Methods and results

Two bipolar voltage maps and two CFAE left atrial maps were obtained each in 30 patients undergoing catheter ablation of AF using the following two different catheters: A four-pole ablation catheter (MAP, mapping and ablation catheter) (electrode size: tip: 4 mm, band: 1 mm; inter-electrode spacing: 0.5-5-2 mm) and a 10-pole circular pulmonary vein mapping catheter (CMC) (electrode size: 1 mm; inter-electrode spacing: 7-7-7 mm). Successively, low-voltage and CFAE area sizes were then compared between the two catheters. Areas with a bipolar voltage of <0.5 mV were significantly smaller when obtained with the CMC compared with the MAP (8.9 ± 8.9 vs. 17.4 ± 11.7 cm², P < 0.001). This was also significantly different for a bipolar voltage of <0.2 mV (2.3 ± 4.6 vs. 6.2 ± 9.6 cm², P < 0.001). Complex fractionated atrial electrogram area sizes were significantly larger when obtained with the CMC compared with the MAP group (14.6 ± 10.9 vs. 19.4 ± 9.4 cm², P = 0.011).

Conclusion

Low-voltage and CFAE area size varies significantly between different mapping catheters. Mapping electrode settings have to be taken into consideration for the assessment of electroanatomical substrate of AF.

Safety and efficacy of catheter-based left atrial appendage closure in patients with contraindications for long-term anticoagulation

BACKGROUND

Percutaneous left atrial appendage closure (LAAC) and the role of postinterventional anticoagulation often evokes controversy in daily practice. This study aimed to evaluate LAAC in patients with non-rheumatic atrial fibrillation, high thromboembolic risk and contraindications for long-term anticoagulation in a clinical scenario.

METHODS

Between 2010-2015, LAAC was attempted in 118 patients (47 women).

RESULTS

Devices were successfully implanted in 95% (Watchman™ device: N.=97; Amplatzer™ Cardiac Plug/Amulet: N.=14; Amplatzer PFO Occluder: N.=1). Mean age was 75±8.35 years. Mean HAS-BLED and CHA2DS2VASc scores were 4.3 and 4.9, respectively. Median follow-up was 447 days (IQR: 183-789 days). The primary safety endpoint was defined as major bleeding according to the International Society on Thrombosis and Hemostasis. The combined efficacy endpoint included ischemic strokes, transitory ischemic attacks (TIA) and systemic embolisms. Procedural complication rate was 3.4%. After successful intervention, either a therapy with anticoagulants (N.=62) or dual antiplatelet therapy (DAPT, N.=50) was prescribed temporarily. Medication was reduced if implantation proved satisfying in a 6-week follow-up transesophageal echocardiography, which was the case in 79% of these patients. During follow-up, one patient suffered a TIA (0.6%/year). No other efficacy event was observed. Eleven major bleedings occurred (6.6%/year): one each under DAPT plus phenprocoumon, DAPT plus rivaroxaban, acetylsalicylic acid (ASA) plus rivaroxaban, two under DAPT, two under ASA plus low molecular weight heparin, and four under ASA only.

CONCLUSIONS

In the present study, catheter-based LAA occlusion prevented thromboembolisms with high efficacy. Major bleedings were however common in patients with, but also without anticoagulation, independent from time course.

Third-degree AV block sensitive to prednisolone 72 hours post AVNRT ablation

A patient developed a transient first‐degree AV block during a radiofrequency ablation of an atrioventricular nodal reentrant tachycardia. Three days later the patient presented with a third‐degree AV block. It resolved within 24 h under antiphlogistic therapy. Patient was asymptomatic without necessity for pacemaker implantation at 12 months follow‐up.

Left atrial strain predicts recurrence of atrial arrhythmias after catheter ablation of persistent atrial fibrillation

Introduction

Success rates of catheter ablation (CA) of persistent atrial fibrillation (AF) are very variable. Identifying patients in whom sinus rhythm maintenance cannot be achieved after CA is a critical issue.

Methods

2D speckle-tracking echocardiography was performed before the first CA procedure in consecutive patients with persistent AF. Left atrial (LA) strain was correlated with recurrence of atrial arrhythmias during the follow-up period of 15 months after one CA procedure with or without antiarrhythmic drugs (primary endpoint). In a secondary analysis, recurrences after two CA procedures were analysed.

Results

102 patients were included. Patients with recurrence of atrial arrhythmias after one CA procedure (n=55) had significantly lower LA strain than those without recurrence (LA strain 9.7±2.4% vs 16.2±3.0%; p<0.001). Recurrence rate was significantly higher in patients with LA strain <10% than in those with LA strain between 10% and 14.5% and >14.5% (97.7%, 42.1% and 10.3%, respectively; p<0.001). In Cox regression analysis including age, comorbidities, left ventricular dysfunction and LA enlargement, low LA strain (<10%) was the strongest factor associated with recurrence of AF (HR 6.4 (2.4–16.9), p<0.001). Even after inclusion of a second CA procedure, LA strain <10% maintained a high predictive value for recurrence of atrial arrhythmias (86.4% (95% CI 73.3% to 93.6%)).

Conclusion

In patients with persistent AF, LA strain imaging could be very useful to select those patients who have a high risk of not benefiting from CA.

High Patient Satisfaction with Deep Sedation for Catheter Ablation of Cardiac Arrhythmia

BACKGROUND

Patients' satisfaction with invasive procedures largely relies on periprocedural perception of pain and discomfort. The necessity for intraprocedural sedation during catheter ablation of cardiac arrhythmias for technical reasons is widely accepted, but data on patients' experience of pain and satisfaction with the procedural sedation are scarce. We have assessed patients' pain and discomfort during and after the procedure using a standardized questionnaire.

METHODS

One hundred seventeen patients who underwent catheter ablation answered a standardized questionnaire on periprocedural perception of pain and discomfort after different anesthetic protocols with propofol/midazolam with and without additional piritramide and ketamine/midazolam.

RESULTS

Patients report a high level of satisfaction with periprocedural sedation with 83% judging sedation as good or very good. The majority of patients was unconscious of the whole procedure and did not recollect experiencing pain. Procedural pain was reported by 7.7% of the patients and 16% reported adverse effects, e.g., postprocedural nausea and episodes of headache.

CONCLUSION

The results of our study show that deep sedation during catheter ablation of cardiac arrhythmias is generally well tolerated and patients are satisfied with the procedure. Yet, a number of patients reports pain or adverse events. Therefore, studies comparing different sedation strategies should be conducted in order to optimize sedation and analgesia.

Improvement of lay rescuer chest compressions with a novel audiovisual feedback device : A randomized trial

BACKGROUND

Bystander actions and skills determine among others the outcome of out-of-hospital cardiac arrest. However, the depth and rate of chest compressions (CC) are difficult to estimate for laypeople and poor CC quality may result. Our study aimed to evaluate the impact of a new feedback device on CC performance by laypeople. The percentage of CC with both correct rate and correct depth of all CC served as primary endpoint.

METHODS

Forty-eight subjects with no medical background performed 2 min of CC on a manikin with and without a novel feedback device (TrueCPR™, Physio-Control, Redmond, Wash.). The device uses a novel, non-accelerometer-based technology. Participants were randomized into two groups. Group 1 performed a 2-min CC trial first with audiovisual feedback followed by a trial with no feedback information, while group 2 performed the task in reverse order.

RESULTS

The absolute percentage of CC with correct rate and depth was significantly higher with the use of the device (59 ± 34% vs. 15 ± 21%, p < 0.0001). The longest interval without correct CC was significantly decreased (76.5 s vs. 27.5 s, p < 0.0001).

CONCLUSION

The quality of CC carried out by laypeople is significantly improved with the use of a new feedback device. The device may be useful for cardiopulmonary resuscitation (CPR) by laypeople and for educational purposes.