Safety of pulsed field ablation in more than 17,000 patients with atrial fibrillation in the MANIFEST-17K study.

Pulsed field ablation (PFA) is an emerging technology for the treatment of atrial fibrillation (AF), for which pre-clinical and early-stage clinical data are suggestive of some degree of preferentiality to myocardial tissue ablation without damage to adjacent structures. Here in the MANIFEST-17K study we assessed the safety of PFA by studying the post-approval use of this treatment modality. Of the 116 centers performing post-approval PFA with a pentaspline catheter, data were received from 106 centers (91.4% participation) regarding 17,642 patients undergoing PFA (mean age 64, 34.7% female, 57.8% paroxysmal AF and 35.2% persistent AF). No esophageal complications, pulmonary vein stenosis or persistent phrenic palsy was reported (transient palsy was reported in 0.06% of patients; 11 of 17,642). Major complications, reported for ~1% of patients (173 of 17,642), were pericardial tamponade (0.36%; 63 of 17,642) and vascular events (0.30%; 53 of 17,642). Stroke was rare (0.12%; 22 of 17,642) and death was even rarer (0.03%; 5 of 17,642). Unexpected complications of PFA were coronary arterial spasm in 0.14% of patients (25 of 17,642) and hemolysis-related acute renal failure necessitating hemodialysis in 0.03% of patients (5 of 17,642). Taken together, these data indicate that PFA demonstrates a favorable safety profile by avoiding much of the collateral damage seen with conventional thermal ablation. PFA has the potential to be transformative for the management of patients with AF.

Impact of pulmonary hypertension on outcomes after TEER in patients suffering from mitral regurgitation.

AIM: Data on associations of invasively determined hemodynamic parameters with procedural success and outcomes in patients suffering from mitral regurgitation (MR) undergoing transcatheter edge-to-edge repair of the mitral valve (M-TEER) is limited. METHODS AND RESULTS: We enrolled 239 patients with symptomatic MR of grade 2 + , who received M-TEER. All patients underwent extensive pre-interventional invasive hemodynamic measurements via right heart catheterization (mean pulmonary arterial pressure (mPAP), systolic- (PAPsys) and diastolic pulmonary arterial pressure (PAPdia), pulmonary arterial wedge pressure (PAWP), a-wave, v-wave, pulmonary vascular resistance (PVR), transpulmonary pressure gradient (TPG), cardiac index (CI), stroke volume index (SVI)). mPAP and PAWP at baseline were neither associated with procedural success, immediate reduction of MR, nor residual MR after 6 months of follow-up. The composite outcome (All-cause mortality (ACM) and/or heart failure induced rehospitalization (HFH)) and HFH differed significantly after M-TEER when stratified according to mPAP, PAWP, PAPdia, a-wave and v-wave. ACM was not associated with the afore mentioned parameters. Neither PVR, TPG, CI nor SVI were associated with the composite outcome and HFH, respectively. In multivariable analyses, PAWP was independently associated with the composite outcome and HFH. PVR and SVI were not associated with outcomes. CONCLUSION: PAWP at baseline was significantly and independently associated with HFH and might serve as a valuable parameter for identifying patients at high risk for HFH after M-TEER. ACM and procedural success were not affected by pulmonary arterial pressure before M-TEER. We suggest that the post-capillary component of PH serves as the driving force behind the risk of HFH.

Interventional Removal of LV Thrombus in a Patient With Cardiogenic Shock and Transitory Ischemic Attack.

We discuss a 38-year-old bodybuilder who had cardiogenic shock and multiorgan failure. The patient developed significant speech disorders resulting from thromboembolism of a huge, volatile left ventricular thrombus. Because of inoperability and the threat of severe ischemic stroke, the thrombus was removed with a snare and application of a cerebral embolic protection device. (Level of Difficulty: Advanced.).

Deceleration capacity of heart rate predicts 1-year mortality in patients undergoing transcatheter edge-to-edge mitral valve repair.

BACKGROUND: Risk stratification for transcatheter procedures in patients with severe mitral regurgitation is challenging. Deceleration capacity (DC) has already proven to be a reliable risk predictor in patients undergoing transcatheter aortic valve implantation. We hypothesized, that DC provides prognostic value in patients undergoing transcatheter edge-to-edge mitral valve repair (TEER). METHODS: We retrospectively analyzed electrocardiogram signals from 106 patients undergoing TEER at the University Hospital of Tübingen. All patients received continuous heart-rate monitoring to assess DC following the procedure. One-year all-cause mortality was defined as the primary end point. RESULTS: Sixteen patients (15.1%) died within 1 year. The DC in nonsurvivors was significantly reduced compared to survivors (5.1 ± 3.0 vs. 3.0 ± 1.6 ms, p = 0.002). A higher EuroSCORE II and impaired left ventricular function were furthermore associated with poor outcome. In Cox regression analyses, a DC < 4.5 ms was found a strong predictor of 1-year mortality (hazard ratio: 0.10, 95% confidence interval: 0.13-0.79, p = 0.029). Finally, a significant negative correlation was found between DC and residual mitral regurgitation after TEER (r = -0.41, p < 0.001). CONCLUSION: In patients with severe mitral regurgitation undergoing TEER, DC may serve as a new predictor of follow-up mortality.

COVID-19 and Cardiac Arrhythmias.

Since the coronavirus disease (COVID-19) pandemic spread unrelentingly all over the world, millions of cases have been reported. Despite a high number of asymptomatic cases, the course of the disease can be serious or even fatal. The affection of the myocardium, called myocardial injury, is caused by multiple triggers. The occurrence of cardiac arrhythmias in COVID-19 patients with myocardial involvement and a critical course is common. In this review, potential mechanisms, incidence, and treatment options for cardiac arrhythmias in COVID-19 patients will be provided by performing a literature research in MESH database and the National Library of Medicine. Common cardiac arrhythmias in COVID-19 patients were sinus tachycardia, atrial fibrillation (AF), ventricular tachycardia (VT), ventricular fibrillation (VF), atrioventricular block, sinusoidal block or QTc prolongation. AF was the most common heart rhythm disorder. About 10% of COVID-19 patients develop new-onset AF and 23 to 33% showed recurrence of AF in patients with known AF. One retrospective trial revealed the incidence of VT or VF to be 5.9% in hospitalized patients. Both AF and VT are clearly associated with worse outcome. Several mechanisms such as hypoxia, myocarditis, myocardial ischemia, or abnormal host immune response, which induce cardiac arrhythmias, have been described. The effect of QT-prolonging drugs in inducing cardiac arrhythmias has become mitigated as these medications are no longer recommended. Acute management of cardiac arrhythmias in COVID-19 patients is affected by the reduction of exposure of health care personnel. More prospective data are desirable to better understand pathophysiology and consecutively adapt management.

Video assisted thoracoscopic sympathectomy for intractable recurrent VT after minimal-invasive LVAD implantation.

BACKGROUND: Recurrent ventricular tachycardia (VT) can occur after left ventricular assist device (LVAD) implantation. In this case, medical treatment might be insufficient. We report a case of a left-sided thoracoscopic sympathectomy as a feasible treatment escalation in intractable VT. CASE REPORT: A 72-year-old patient underwent an internal cardioverter defibrillator (ICD) implantation as primary prophylaxis for VTs in the setting of staged heart failure therapy. Afterwards, due to a progressive dilative cardiomyopathy he underwent a minimal-invasive LVAD implantation (HeartWare, Medtronic). After an uneventful minimal-invasive LVAD-implantation the patient was discharged to a rehabilitation program. However, after 7 weeks he developed recurrent VTs which were successfully terminated by ICD shocks deliveries leading to severe discomfort and frequent hospitalizations. Eventually, the patient was admitted with an electrical VT storm. Successful endocardial catheter ablation of all inducible VTs were performed combined with multiple rearrangements of his oral antiarrhythmic medication. However, all these treatments could not suppress further occurrence of VTs. After an interdisciplinary discussion the patient agreed to a left-sided video-assisted thoracoscopic sympathectomy. After a follow up of 150 days the patient was free from VTs apart from one short event. CONCLUSION: We believe video-assisted thoracoscopic sympathectomy might be a surgical treatment option in patients with intractable recurrent VTs after catheter ablation of VT reentrant substrate even after minimal-invasive LVAD implantation.

Deep Sedation in a Patient Undergoing Transfemoral Tricuspid Valve Repair Using the PASCAL System.

A 70-year-old man with severe tricuspid regurgitation and large coaptation gap (0.8 cm) was referred to transfemoral valve repair using the PASCAL system. The procedure was successful in reducing tricuspid regurgitation. The PASCAL device facilitated maximum leaflet insertion and to span large coaptation gap in severe tricuspid regurgitation without ventilation maneuvers under general anesthesia. (Level of Difficulty: Intermediate.).

ECG changes after percutaneous edge-to-edge mitral valve repair.

BACKGROUND: Mitral regurgitation (MR) has a severe impact on hemodynamics and induces severe structural changes in the left atrium. Atrial remodeling is known to alter excitability and conduction in the atrium facilitating atrial fibrillation and atrial flutter. PMVR is a feasible and highly effective procedure to reduce MR in high-risk patients, which are likely to suffer from atrial rhythm disturbances. So far, electroanatomical changes after PMVR have not been studied. HYPOTHESIS: In the current study, we investigated changes in surface electrocardiograms (ECGs) of patients undergoing PMVR for reduction of MR. METHODS: We evaluated 104 surface ECGs from patients in sinus rhythm undergoing PMVR. P wave duration, P wave amplitude, PR interval, QRS duration, QRS axis, and QT interval were evaluated before and after PMVR and at follow-up. RESULTS: We found no changes in QRS duration, QRS axis, and QT interval after successful PMVR. However, P wave duration, amplitude, and PR interval were significantly decreased after reduction of MR through PMVR (P < .05, respectively). CONCLUSION: The data we provide offers insight into changes in atrial conduction after reduction of MR using PMVR in patients with sinus rhythm.

Cryoballoon ablation for persistent atrial fibrillation in patients without left atrial fibrosis.

INTRODUCTION: The role of cryoballoon (CB) pulmonary vein isolation (PVI) for patients with persistent atrial fibrillation (AF) is controversial, since long-term success can be poor. We performed left atrial voltage mapping before CB PVI and determined AF-free survival depending on the extent of low-voltage areas (LVAs). METHODS AND RESULTS: We consecutively enrolled 60 patients with persistent AF (average age, 60.6 ± 12.9 years; CHA2 DS 2 VASc score, 2.3 ± 1.6; and left atrial size 46.0 ± 5.2 mm) who were planned for CB PVI. Before ablation, we performed left atrial voltage mapping (Abbott EnSite Precision or Velocity). LVAs were defined if local bipolar signal amplitudes were less than 0.5 mV during sinus rhythm. Thirty-seven patients did not show significant LVAs (<10%), while 12 patients had LVAs between 10% and 30% and 11 patients showed substantial LVAs greater than 30% of the left atrial area. CB PVI could be successfully performed in all patients. A 7-day holter monitoring was obtained 3, 6, and 12 months after ablation. After a 12-month follow-up time, 83.8% of patients without LVAs (<10%) were free of atrial fibrillation, while 50.0% of patients with 10% to 30% LVAs and 9.1% of patients with LVAs more than 30% had stable sinus rhythm. The degree of atrial fibrosis correlated with the risk of AF recurrence. CONCLUSION: In patients with persistent AF undergoing CB PVI, the extent of left atrial LVAs predicts an AF-free survival. CB PVI seems to be a highly effective treatment for patients with persistent AF without atrial fibrosis.

Mitochondrial Dynamics in Tachycardiomyopathy.

BACKGROUND/AIMS: Tachycardiomyopathy (TCM) is a largely reversible form of non-ischemic heart failure. The underlying mechanism are, however, still today poorly understood. Recent data indicate distinct changes in mitochondrial distribution in these patients, compared to other non-ischemic cardiomyopathies.This study investigated underlying mechanisms in mitochondrial dynamics in endomyocardial biopsy samples (EMB) from patients with TCM and compared them to patients with dilated cardiomyopathy (DCM), which show similar clinical features. METHODS: Focused mRNA analyses were performed on routinely obtained paraffinfixed EMB specimen from patients fulfilling TCM diagnosis criteria, as well as patients with DCM to elucidate regulatory changes in mitochondrial fusion, fission and mitophagy. RESULTS: In patients with TCM we were able to identify mRNA of Mitofusin 1 and 2, two effector proteins regulating mitochondrial fusion, to be strongly upregulated compared to patients with DCM. Conclusively, we did not find differences in the mRNA expression of mitochondrial fission regulators including DRP1, Fis1, MFF, MiD49, and MiD51. Furthermore, we did not find significant changes in PINK1 expression, an important mediator for mitochondrial autophagy. CONCLUSION: The mRNA upregulation of Mitofusin 1 and 2 provides first insight into the complex changes of mitochondrial dynamics in cardiomyocytes of patients with reversible heart failure due to TCM.

Prognostic Value of Atrial Fibrillation Inducibility in Patients Without History of Clinical Atrial Fibrillation.

PURPOSE: During invasive electrophysiological studies (EPS), atrial fibrillation (AF) can be induced in patients without a history of AF. However, the prognostic value is not well evaluated in this population. Our aim was to investigate whether AF inducibility in those patients is associated with future clinical episodes of AF; whether non-inducibility is predictive of freedom from new-onset AF and finally, to examine clinical factors associated with inducibility. METHODS: Medical records from patients undergoing EPS between the years 2011 and 2014 were analysed retrospectively with 62 patients matching our inclusion criteria. Patients were divided into subgroups according to their inducibility status and underwent follow-up. Patients were assessed by a structured telephone interview, data from the further treating physicians and ECG recordings. RESULTS: AF was inducible in 19 patients ("induction group") and not inducible in the remaining 43 ("control group"). Inducibility was associated with a higher age (p=0.002), lower GFR (p=0.002), higher CHAD2S2-VASc score (p=0.004) and diagnosis of mitral (p=0.014), tricuspid (p=0.017) and pulmonary (p=0.026) valve insufficiency. Three months after EPS, 89.5% of all inducible patients were free of diagnosed AF, in contrast to 100% of those without inducibility (p=0.031). At three years, no significant difference was left (p=0.162). CONCLUSION: AF inducibility was found more often in an older population with cardiac comorbidities. While inducibility was associated with an increased rate of diagnosed new-onset clinical AF in the months after testing, non-inducibility seemed to be associated with freedom from AF at least in the short to medium term. However, there was no significant difference in the long term follow-up.

Formation of a left atrial thrombus during percutaneous mitral valve edge-to-edge repair induced by acute reduction of mitral regurgitation.

Percutaneous mitral valve repair (PMVR) using the MitraClip system (Abbott, Abbott Park, IL, USA) is an innovative method allowing treatment of mitral regurgitation (MR) for patients that are not accessible by conventional operation. Thrombogenicity in the left atrium (LA) in general is increased in the presence of atrial fibrillation and mitral valve disease. We observed in a patient who underwent PMVR an acute change in thrombogenicity in the LA with thrombus formation in the left atrial appendix (LAA) immediately after clip placement. Thrombus formation occurred under verified therapeutic anticoagulation using unfractionated heparin. To our knowledge this is the first patient with documented acute and solid intra-interventional thrombus formation. The observation implies that acute reduction of mitral valve regurgitation and changes in hemodynamics within the LA enhances the risk of thrombus formation. .

Previous TAVR in patients undergoing percutaneous edge-to-edge mitral valve repair (PMVR) affects improvement of MR.

BACKGROUND: Patients after transcatheter aortic valve replacement (TAVR) and persistent severe mitral regurgitation (MR) are increasingly treated with percutaneous edge-to-edge mitral valve repair (PMVR). The impact of a former TAVR on PMVR procedures is not clear. METHODS AND RESULTS: We retrospectively analyzed 332 patients undergoing PMVR using the MitraClip system with respect to procedural and clinical outcome. 21 of these 332 patients underwent TAVR before PMVR. Intra-procedural transthoracic (TTE) and transesophageal echocardiograms (TEE) immediately before and after clip implantation as well as invasive hemodynamic measurements were evaluated. At baseline, we found a significantly smaller mitral valve anterior-posterior diameter in the TAVR cohort (p < 0.001). A reduction of MR by at least three grades was achieved in a smaller fraction in the TAVR cohort as compared to the cohort with a native aortic valve (p = 0.02). Accordingly, we observed a smaller post-procedural cardiac output in the TAVR cohort (p = 0.02). CONCLUSION: PMVR in patients who had a TAVR before, is associated with altered MR anatomy before and a reduced improvement of MR after the procedure. Future larger and prospective studies will have to determine, whether a previous TAVR influences long-term clinical outcome of patients undergoing PMVR.

TGFß Is Specifically Upregulated on Circulating CD14++ CD16+ and CD14+ CD16++ Monocytes in Patients with Atrial Fibrillation and Severe Atrial Fibrosis.

BACKGROUND/AIMS: Fibrotic remodeling of the atria plays a key role in the pathogenesis of atrial fibrillation (AF). As little is known about the contribution of circulating monocytes in atrial remodeling and the pathophysiology of AF, we investigated profibrotic factors in different subsets of circulating monocytes obtained from patients with atrial fibrillation undergoing catheter ablation. METHODS: A 3D high density voltage mapping was performed in sinus rhythm to evaluate the extent of low-voltage areas (LVAs) in the atria of 71 patients with persistent AF. Low-voltage was defined as signals of < 0.5mV during sinus rhythm. Prior to ablation, blood was drawn and monocytes were analyzed by FACS. Based on the expression of CD14 and CD16, three subgroups including CD14++ CD16- ('classical'), CD14++ CD16+ ('intermediate'), and CD14+ CD16++ ('non-classical') were analyzed for the expression of TGFb, CD147, and MMP-9, representing pivotal profibrotic pathways in myocardial remodeling. RESULTS: Expression of TGFb was increased in CD14+ monocytes of patients with extensive LVAs compared to patients with a low extend of LVAs. While CD14++ CD16- monocytes showed no difference, CD14++ CD16+ and CD14+ CD16++ monocytes showed a strong increase of TGFb abundance. Although CD147 and MMP-9 are strongly associated with myocardial fibrosis, we found no difference in expression between the two groups in any monocyte subsets. CONCLUSION: TGFb is specifically upregulated on CD14++ CD16+ and CD14+ CD16++ monocytes in patients with extensive LVAs undergoing catheter ablation.

Circulating MicroRNA-21 Correlates With Left Atrial Low-Voltage Areas and Is Associated With Procedure Outcome in Patients Undergoing Atrial Fibrillation Ablation.

BACKGROUND: Atrial fibrosis is a hallmark of arrhythmogenic structural remodeling in patients with persistent atrial fibrillation (AF) and is negatively correlated with procedure outcome in patients undergoing ablation. However, noninvasive methods to determine the extent of atrial fibrosis are limited. Here, we used microRNA (miRNA) expression analysis to detect markers of left atrial low-voltage areas (LVAs) in patients with persistent AF undergoing catheter ablation. METHODS: We performed 3-dimensional voltage mapping in 102 patients (average age 62.1±13.1 years, CHA2DS2-VASc score of 2.3±1.6, LA size 41.5±5.7 mm) undergoing ablation for persistent AF and determined the extent of left atrial low-voltage. LVAs were defined if bipolar electrogram amplitudes were <0.5 mV during sinus rhythm. Before ablation, we obtained a blood sample, isolated miRNAs, and profiled them on a miRCURY LNA Universal RT microRNA PCR Human panel. RESULTS: Sixty-nine miRNAs were identified in all samples, with an average of 123 miRNAs detectable per sample. We found that the serum concentration of miR-21, a miRNA that has been previously linked to cardiac fibrosis development, was strongly associated with the extent of LVAs determined by voltage mapping. We could confirm that LVAs were negatively correlated with ablation success in a 1-year follow-up. In addition, miR-21 serum levels were associated with AF-free survival after catheter ablation. CONCLUSIONS: Circulating miR-21 correlates with left atrial LVAs and is associated with procedure outcome in patients with persistent AF undergoing ablation.