The ECG in sarcoidosis - a marker of cardiac involvement? Current evidence and clinical implications.

Sarcoidosis is a multisystem granulomatous disease of unknown etiology characterized by noncaseating granulomas. Cardiac involvement is often limiting patients' prognosis. Cardiac sarcoidosis can manifest with variant cardiac arrhythmias, of which atrioventricular (AV)-block-related bradycardia and ventricular tachycardias are the most common. Although cardiac sarcoidosis remains a histopathological diagnosis, the significance of imaging modalities, especially cardiac magnetic resonance imaging is increasing rapidly but mainly remains reserved for patients with a high suspicion due to a previous arrhythmia or unknown cardiomyopathy. Thus, there is a need for screening in daily clinical practice so that possible characteristic electrocardiographic (ECG) findings may guide the way to detect the disease. We therefore evaluated the ECG as a potential tool for screening of cardiac sarcoidosis and present different electrophysiological manifestations of cardiac sarcoidosis based on a literature review. The ECG is a valuable tool for screening of cardiac involvement in patients with sarcoidosis. Several parameters have been shown to be associated with cardiac involvement in sarcoidosis such as higher-degree AV-block, QRS complex fragmentation and widening, as well as certain T wave abnormalities that may indicate cardiac involvement, of which the latter two are most promising and specific. However, prospective studies examining a large number of trials are desirable.

Ablation of paroxysmal and persistent atrial fibrillation in the very elderly real-world data on safety and efficacy.

BACKGROUND: The role and technique of catheter ablation of atrial fibrillation (AF) in the elderly is unclear. While in young patients pulmonary vein isolation (PVI) has evolved as first option, in older patients decision is often made in favor of drugs as higher complication rates and less benefit are suspected. Therefore, data on PVI of paroxysmal and persistent AF in these patients is still sparse but of eminent importance. HYPOTHESIS: PVI is comparably safe in the very elderly with similar recurrence and complication rates. METHODS: We enrolled all patients (n = 146) aged >75 years who underwent a first PVI over a period of 10 years (2009-2019) from our prospective single-center ablation registry. Mean follow-up time was 231 ± 399 days. RESULTS: Acute ablation success defined as complete PVI and sinus rhythm at the end of the ablation procedure was high (99%). Severe periprocedural complications occurred in 3.3% (stroke/TIA n = 2; 1.3%; pericardial effusion n = 3; 2%). In 4.6% of patients symptomatic sick-sinus-syndrome was unmasked after PVI resulting in pacemaker implantation. There were no deaths related to PVI. Recurrence rate of symptomatic AF was 37.3% resulting in a Re-PVI and/or substrate ablation in 32 pts (20.9%). During follow-up pacemaker implantation plus atrioventricular node ablation was performed in 10 pts (6.8%). There was a trend toward lower recurrence rates with single-shot devices (cryoballoon, multielectrode phased-radiofrequency ablation catheter) than with point-by-point radiofrequency while complication rates did not differ. CONCLUSION: PVI for AF is a feasible treatment option also in patients >75 years with a reasonable success and safety profile. Higher success rates occurred in patients treated with a single-shot device as compared to point-by-point ablation.

Outcome of catheter ablation of supraventricular tachyarrhythmias in cardiac sarcoidosis.

BACKGROUND: Sarcoidosis is a multisystem granulomatous disease of not sufficiently understood origin. Some patients develop cardiac involvement in course of the disease which is mostly responsible for adverse outcome. In addition to complications like high degree atrioventricular (AV) block or ventricular tachyarrhythmias, there is a certain percentage of patients developing atrial tachyarrhythmias. Data is limited and the role of catheter ablation uncertain. Therefore, we studied sarcoid patients who presented with supraventricular tachyarrhythmias. HYPOTHESIS: Treatment and ablation of supraventricular tachycardia could be hampered by inflammation in patients with cardiac sarcoidosis. METHODS: We enrolled 37 consecutive patients with cardiac sarcoidosis who presented with atrial tachyarrhythmias and underwent an electrophysiologic study over a period of 6 years (03/2013-04/2019). In total, 16 catheter ablations for atrial tachyarrhythmias were performed. Mean follow-up duration was 2.5 years. RESULTS: Most common ablation performed was cavo-tricuspid isthmus ablation for typical atrial flutter in seven patients (54%). Pulmonary vein isolation for treatment of atrial fibrillation (AF) was performed in five patients (38%). Two patients received slow-pathway modulation for treatment of recurrent atrioventricular nodal reentry tachycardia (AVNRT). All but two patients with AF had no clinical recurrence during follow-up. Two patients had recurrence of AF but still reported markedly improved european heart rhythm association (EHRA) class. Periprocedural safety was very high. There were no adverse events related to the ablation procedure. One patient died during follow-up in the presence of electrical storm. CONCLUSION: Catheter ablations of supraventricular tachycardias seem to be safe and effective in patients with cardiac sarcoidosis. Outcome is comparable to patients without inflammatory heart disease, although data from larger patient collectives are mandatory to make recommendations in this special entity.

Direct comparison of the novel automated screening tool (AST) versus the manual screening tool (MST) in patients with already implanted subcutaneous ICD.

BACKGROUND: The subcutaneous implantable cardioverter-defibrillator (S-ICD) has evolved as a valuable alternative to the transvenous ICD, especially in young patients. Unfortunately, some of these patients are ineligible for S-ICD implantation due to specific electrocardiographic features. So far, these patients were identified by mandatory pre-implantation screening using the manual screening tool (MST), which lacks objective value. Therefore, a novel automated screening tool (AST) has been introduced recently for objective screening, which has not been evaluated yet. METHODS/RESULTS: We here first investigate the novel AST, in direct comparison to MST, in 33 consecutive patients with already implanted S-ICD system to compare predicted eligibility by screening tools with true sensing of the S-ICD system. Both screening tools reliably predicted true ineligible single vectors, but also suggested overall ineligibility in a similar fraction of patients (MST: 3.0%; AST: 6.1%), albeit the implanted S-ICD worked flawlessly in these patients. AST did not predict the finally selected sensing vector better than MST. There was a surprising mismatch between AST and MST for the predicted eligibility of single vectors; only in 49% of patients did both screening tools predict eligibility for the same vectors. CONCLUSIONS: The novel AST predicted overall eligibility approximately similar to MST. Both tools predicted ineligibility in a few patients, who were actually eligible. There was a striking mismatch between both screening tools when eligibility of single vectors was predicted. Thus, the AST seems to be a valuable advance, due to its standardized and objective process, but it still lacks specificity.

[Management of inappropriate shocks/T-wave-oversensing in S-ICD®-patients]. / Management von inadäquaten Schocks/T-Wellen-Oversensing bei S-ICD®-Patienten.

Inappropriate shocks are a feared complication after implantable cardioverter-defibrillator (ICD) implantation and have a tremendous impact on quality of life. Inappropriate shocks in patients with subcutaneous ICD (S-ICD®, Boston Scientific, Marlborough, MA, USA) have various underlying causes. This review summarizes the current literature on this topic and lists possible treatment options.

Divergent antiarrhythmic effects of resveratrol and piceatannol in a whole-heart model of long QT syndrome.

BACKGROUND: The polyphenol resveratrol and its metabolite piceatannol have beneficial health effects including antiarrhythmic properties in ischemia/reperfusion. The objective of this study was to determine potential antiarrhythmic effects in acquired long-QT-syndrome (LQTS). METHODS AND RESULTS: 26 rabbit hearts were isolated and Langendorff-perfused. The IKr-blocker sotalol (100µM) was infused to mimic LQTS-2. Hearts were assigned to two groups. Sotalol significantly prolonged action potential duration (APD90) and QT-interval in both groups (group 1:APD90: +18ms, p<0.01;QT: +59ms, p<0.01; group 2: APD90: +22ms, p<0.01; QT: +30ms, p<0.01) and also significantly increased dispersion of repolarization (group 1: +21ms, p<0.01; group 2: +23ms, p<0.01). Thereafter, hearts were additionally perfused either with resveratrol (50µM, group 1, n=14) or with piceatannol (10µM, group 2, n=12). Administration of resveratrol significantly reduced APD90 (-29ms, p<0.01), QT-interval(-60ms, p<0.01) and dispersion of repolarization (-26ms, p<0.01). In contrast, piceatannol did not significantly alter APD90 (±0ms) but shortened QT-interval (-19ms, p<0.01) and increased dispersion of repolarization (+15ms, p<0.01). With sotalol, 7 of 14 bradycardic, AV-blocked hearts in group 1 and 8 of 12 in group 2 showed early afterdepolarizations (EAD) after lowering potassium concentration (p<0.01each). Polymorphic ventricular tachycardia (PVT) occurred in 5 of 14 (p<0.05) and 4 of 12 hearts (p=0.09) with a total number of 42 (p<0.05) and 44 episodes (p=0.07), respectively. Additional infusion of resveratrol reduced EAD (2 of 14, p=0.11) and PVT (1 of 14 hearts, p=0.16, 3 episodes, p<0.05). Piceatannol did not suppress EAD or TdP (EAD in 9 of 12 and TdP in 7 of 12 hearts,50 episodes). CONCLUSION: Resveratrol showed beneficial antiarrhythmic properties in acquired LQTS. Underlying mechanism is a substantial decrease dispersion of repolarization leading to a suppression of triggered activity.