Atrial fibrillation ablation workflow optimization facilitated by high-power short-duration ablation and high-resolution mapping.

AIMS: Pulmonary vein isolation (PVI) for catheter ablation of atrial fibrillation (AF) is a time-demanding procedure. High-power short-duration (HPSD) ablation protocols and high-density mapping catheters have recently been introduced to clinical practice. We investigated the impact of high-density mapping and HPSD ablation protocols on procedural timing, efficacy, and safety by comparing different standardized set-ups. METHODS AND RESULTS: Three electrophysiology (EP) laboratory set-ups were analysed: (i) circular catheter for mapping and HPSD ablation with 30/35 W guided by an ablation index (AI); (ii) pentaspline catheter for mapping an HPSD ablation with 50 W guided by an AI; and (iii) pentaspline catheter for mapping and HPSD ablation with 90 W over 4 s using a novel ablation catheter. All patients underwent PVI without additional left atrial ablation strategies. Procedural data and operating intervals in the EP laboratory were systematically analysed. Three hundred seven patients were analysed (30/35 W AI: n = 102, 50 W AI: n = 102, 90 W/4 s: n = 103). Skin-to-skin times [105.3 ± 22.7 (30/35 W AI) vs. 81.4 ± 21.3 (50 W AI) vs. 69.5 ± 12.2 (90 W/4 s) min, P ≤ 0.001] and total laboratory times (132.8 ± 42.1 vs. 107.4 ± 25.7 vs. 95.2 ± 14.0 min, P < 0.001) significantly differed among the study groups. Laboratory interval analysis revealed significant shortening of mapping and ablation times. Arrhythmia-free survival after 12 months was not different among the study groups (log-rank P = 0.96). CONCLUSION: The integration of high-density mapping and HPSD protocols into an institutional AF ablation process resulted in reduced procedure times without compromising safety or efficacy.

Magnetic resonance assessment of left atrial scar formation following a novel very high-power short-duration workflow for atrial fibrillation ablation.

AIMS: Atrial fibrillation (AF) ablation protocols using energy delivery with very high power and short duration (vHPSD) have been introduced to improve lesion formation. This study reports procedural data of vHPSD ablation in AF patients and analyses characteristics of ablation-induced left atrial (LA) scar formation from cardiac magnetic resonance imaging (MRI). METHODS AND RESULTS: Sixty consecutive patients undergoing index pulmonary vein isolation following our institutional Q4U-AF workflow were prospectively enrolled. Ablation was conducted using a contact force sensing catheter allowing for vHPSD ablation using a temperature-controlled ablation mode. Thirty patients underwent cardiac late gadolinium enhancement MRI of the LA 3 months after ablation to assess LA scar. Mean procedural duration was 66.5 ± 14.8 min. Mean ablation time was 4.7 ± 0.9 min with a mean number of 69.9 ± 14.2 applications. First-pass isolation was achieved in 51 patients (85%) for the right pulmonary veins (RPVs), in 37 patients (61.7%) for the left pulmonary veins (LPVs), and in 34 patients (56.7%) for both pulmonary veins (PVs). Magnetic resonance imaging at 3 months post-ablation demonstrated a mean scar width of 14.4 ± 2.6 mm around RPVs and 11.9 ± 1.9 mm at LPVs (P > 0.05). Complete PV encirclement was observed in 76.7% for RPVs, in 76.7% for LPVs, and in 66.7% for both PV pairs. During a mean follow-up of 4.7 ± 1.4 months, arrhythmia recurrence was observed in 3.3% of the patients. CONCLUSION: Pulmonary vein isolation following a novel vHPSD workflow resulted in short procedure duration and high acute and mid-term efficacy. Magnetic resonance imaging demonstrated durable and transmural PV lesions with homogeneous and contiguous scar formation.

EASY-WPW: a novel ECG-algorithm for easy and reliable localization of manifest accessory pathways in children and adults.

AIMS: Accessory pathway (AP) ablation is a standard procedure for the treatment of Wolff-Parkinson-White syndrome (WPW). Twelve-lead electrocardiogram (ECG)-based delta wave analysis is essential for predicting ablation sites. Previous algorithms have shown to be complex, time-consuming, and unprecise. We aimed to retrospectively develop and prospectively validate a new, simple ECG-based algorithm considering the patients' heart axis allowing for exact localization of APs in patients undergoing ablation for WPW. METHODS AND RESULTS: Our multicentre study included 211 patients undergoing ablation of a single manifest AP due to WPW between 2013 and 2021. The algorithm was developed retrospectively and validated prospectively by comparing its efficacy to two established ones (Pambrun and Arruda). All patients (32 ± 19 years old, 47% female) underwent successful pathway ablation. Prediction of AP-localization was correct in 197 patients (93%) (sensitivity 92%, specificity 99%, PPV 96%, and NPV 99%). Our algorithm was particularly useful in correctly localizing antero-septal/-lateral (sensitivity and specificity 100%) and posteroseptal (sensitivity 98%, specificity 92%) AP in proximity to the tricuspid valve. The accuracy of EASY-WPW was superior compared to the Pambrun (93% vs. 84%, P = 0.003*) and the Arruda algorithm (94% vs. 75%, P < 0.001*). A subgroup analysis of children (n = 58, 12 ± 4 years old, 55% female) revealed superiority to the Arruda algorithm (P < 0.001*). The reproducibility of our algorithm was excellent (Ï°>0.8; P < 0.001*). CONCLUSION: The novel EASY-WPW algorithm provides reliable and accurate pre-interventional ablation site determination in WPW patients. Only two steps are necessary to locate left-sided AP, and three steps to determine right-sided AP.

Lesion formation following pulsed field ablation for pulmonary vein and posterior wall isolation.

BACKGROUND: Pulsed field ablation (PFA) results in unique lesion formation, but there is lack of in-vivo validation in terms of scar formation following atrial fibrillation (AF) ablation. OBJECTIVE: We aimed to access atrial lesion formation based on late gadolinium enhancement (LGE) cardiovascular magnetic resonance imaging (CMR) following PFA for pulmonary vein (PV) and posterior wall isolation (PWI). METHODS: AF ablation was performed in 10 patients using a 31 mm pentaspline PFA catheter. After pulmonary vein isolation (PVI; n = 8 PFA-applications/ PV; n = 4 in basket and n = 4 in flower configuration), another eight applications in flower configuration were conducted for concomitant PWI. Patients underwent LGE CMR 3 months after ablation aiming for quantification of left atrial (LA) scar. RESULTS: Acute procedural success was achieved in all patients. Mean procedure duration was 62 ± 7 min. and mean LA dwell time of the PFA catheter was 13 ± 2 min. Mean post ablation total LA scar burden was 8.1 ± 2.1% and mean scar width was 12.8 ± 2.1 mm. At the posterior LA, 22.6 ± 2.2% of the anatomical segment resulted in chronic scar tissue, concentrated at the PW. Postablation CMR found no evidence for PV stenosis or collateral damage of adjacent structures. At 7 months of follow-up, 9/10 patients (90%) were free from arrhythmia recurrence. CONCLUSION: PFA for AF resulted in durable and transmural atrial scar tissue at the PVs and PW. LGE CMR found a very homogeneous and contiguous lesion pattern with no signs for collateral damage.

The individual relationship between atrial fibrillation sources from CARTOFINDER mapping and atrial cardiomyopathy: The catch me if you can trial.

BACKGROUND: Targeting individual sources identified during atrial fibrillation (AF) has been used as an ablation strategy with varying results. OBJECTIVE: Aim of this study was to evaluate the relationship between regions of interest (ROIs) from CARTOFINDER (CF) mapping and atrial cardiomyopathy from late gadolinium enhancement (LGE) cardiovascular magnetic resonance imaging (CMR). METHODS: Twenty consecutive patients underwent index catheter ablation for persistent AF (PERS AF). Pre-processed LGE CMR images were merged with the results from CF mapping to visualize harboring regions for focal and rotational activities. Atrial cardiomyopathy was classified based on the four Utah stages. RESULTS: Procedural success was achieved in all patients (n = 20, 100%). LGE CMR revealed an intermediate amount of 21.41% ± 6.32% for LA fibrosis. ROIs were identified in all patients (mean no ROIs per patient n = 416.45 ± 204.57). A tendency towards a positive correlation between the total amount of atrial cardiomyopathy and the total number of ROIs per patient (regression coefficient, ß = 10.86, p = .15) was observed. The degree of fibrosis and the presence of ROIs per segment showed no consistent spatial correlation (posterior: ß = 0.36, p-value (p) = .24; anterior: ß = -0.08, p = .54; lateral: ß = 0.31, p = 39; septal: ß = -0.12; p = .66; right PVs: ß = 0.34, p = .27; left PVs: ß = 0.07, p = .79; LAA: ß = -0.91, p = .12). 12 months AF-free survival was 70% (n = 14) after ablation. CONCLUSION: The presence of ROIs from CF mapping was not directly associated with the extent and location of fibrosis. Further studies evaluating the relationship between focal and rotational activity and atrial cardiomyopathy are mandatory.

First clinical experience using a novel automated mapping algorithm for mapping of ventricular arrhythmias.

A new automated vector-based mapping algorithm (AMA) for 3-dimensional (3D) mapping has been introduced. The aim of this study was to present our experience using AMA to recognize additional catheter ablation targets in patients with ventricular arrhythmias (VA). A total of 16 patients (ICM; ischemic cardiomyopathy, n = 6; NICM; non-ischemic cardiomyopathy n = 10) suffering from VA underwent catheter ablation. Following bipolar voltage mapping, AMA was utilized to reveal zones of decelerated conduction velocity vectors (CVV) and this information was superimposed onto the 3D reconstructions and compared with the presence of scar. Mapping time was 28.1 ± 10 min for the endocardial reconstruction of the left ventricle (LV) and 17 ± 5.4 min for the epicardium (n = 6 patients). The mean area of LV low voltage was 13.9 ± 15% (endocardial) and 11.9 ± 5.7% (epicardial). Decelerating CVV zones were revealed in all patients (mean conduction velocity threshold of 39.3 ± 13%). Sustained VA have been terminated through ablation and substrate modification was performed in all patients. Correlation between the presence of CVV deceleration zones and areas of abnormal low voltage from bipolar mapping was revealed in only 37.5% of patients, but there was good correlation between scar from unipolar voltage mapping and the presence of CCV deceleration zones (94%; p = 0.008). The novel AMA may improve the understanding of individual VA substrates due to the visualization of decelerated CVV zones and their correlation with abnormal low voltage predominantly from unipolar mapping.

Direct comparison of two 50 W high power short duration approaches-Temperature- versus ablation index-guided radiofrequency ablation for atrial fibrillation.

INTRODUCTION: Approaches applying higher energy levels for shorter periods (high power short duration, HPSD) to improve lesion formation for atrial fibrillation (AF) ablation have been introduced. This single-center study aimed to compare the efficacy, safety, and lesion formation using the novel DiamondTemp (DT) catheter or an ablation index (AI)-guided HPSD ablation protocol using a force-sensing catheter with surround-flow irrigation. METHODS: One hundred thirteen consecutive patients undergoing radiofrequency-guided catheter ablation (RFCA) for AF were included. Forty-five patients treated with the DT catheter (50 W, 9 s), were compared to 68 consecutive patients undergoing AI-guided ablation (AI anterior 550; AI posterior 400) adherent to a 50 W HPSD protocol. Procedural data and AF recurrence were evaluated. RESULTS: Acute procedural success was achieved in all patients (n = 113, 100%). DT-guided AF ablation was associated with a longer mean procedure duration (99.10 ± 28.30 min vs. 78.24 ± 25.55, p < .001) and more RF applications (75.24 ± 30.76 min vs. 61.27 ± 14.06, p = .019). RF duration (792.13 ± 311.23 s vs. 1035.54 ± 287.24 s, p < .001) and fluoroscopy dose (183.81 ± 178.13 vs. 295.80 ± 247.54 yGym2 , p = .013) were lower in the DT group. AI-guided HPSD was associated with a higher AF-free survival rate without reaching statistical significance (p = .088). Especially patients with PERS AF (p = .009) as well as patients with additional atrial arrhythmia substrate (p = .002) benefited from an AI-guided ablation strategy. CONCLUSION: Temperature- and AI- controlled HPSD RFCA using 50 W was safe and effective. AI-guided HPSD ablation seems to be associated with shorter procedure durations and fewer RF applications. Particularly in advanced AF, freedom from AF-recurrence may be improved using an AI-guided HPSD approach.

AV-node isolation as an alternative to AV-node ablation in patients undergoing pace & ablate strategy.

INTRODUCTION: Atrioventricular (AV)-node ablation (AVNA) is a common therapy option for rate control strategy of permanent atrial fibrillation (AF). We hypothesized that isolation of the AV nodal isolation (AVNI) is associated with a more frequent preservation of an adequate escape rhythm compared to AVNA. METHODS: This retrospective study included 20 patients with therapy-refractory AF being treated with AVNI and 40 historical AVNA-controls. In AVNI the AV-node region was mapped using a 3D mapping system. Ablation was performed around the previously mapped HIS-cloud regions isolating the atrium from the AV-node. In the AVNI group, ablation was performed with irrigated tip ablation catheter in all cases. The two approaches were compared regarding rate of escape rhythm, delta QRS, and procedural data. RESULTS: The number of patients with adequate escape rhythm in AVNI was significantly superior to AVNA immediately postoperative (90% vs. 40%, p < 0.01) and during follow-up (77% vs. 36%, p < 0.05). The median change in QRS width was 0 ms in AVNI versus +26 ms in AVNA (p < 0.01). Thirty percent new bundle branch blocks in AVNA were observed compared to 0% in AVNI (p < 0.01). In the AVNI group, fluoroscopy time and total dose area product were significantly lower (p < 0.01). CONCLUSION: The present study suggests that AV-node isolation using 3D navigation mapping system is a feasible and effective alternative to conventional AVNA. The precise application of radiofrequency lesions preserves a stable AV-junctional rhythm.

A frozen decade: Ten years outcome of atrial fibrillation ablation using a single shot device for pulmonary vein isolation.

AIMS: Cryoballoon-guided pulmonary vein isolation (CB-PVI) for symptomatic atrial fibrillation (AF) has become an established treatment option with encouraging results in terms of safety and efficacy. Data reporting on long-term data beyond a follow-up (FU) period of 5 years is scarce. This prospective study aimed to evaluate very long-term outcome after CB-PVI for AF. METHODS: Data from consecutive patients treated with CB-PVI for symptomatic and drug refractory AF between 2005 and 2012 were analyzed. Patients with a FU of ≥9 years after index CB-PVI were included. All patients were continuously followed-up in our outpatient clinic. Arrhythmia recurrence was defined as AF or atrial tachycardia (AT) lasting >30 s beyond a 3-month blanking period. RESULTS: A total of 385 patients (71% male) were included. Mean age was 58 ± 10 years and paroxysmal AF was present in 93% of patients. Mean FU duration was 124 ± 24 months. At the end of the observational period, 73% of all patients were in stable sinus rhythm after a mean of 2 ± 0.8 ablation procedures. Patients with AF/AT recurrence were older (60 ± 8 vs. 57 ± 10 years; p = .019), had a higher CHA2 DS2 -Vasc Score (2.47 ± 1.46 vs. 1.98 ± 1.50; p = .01) and presented with a larger left atrium (LA)-diameter (43 ± 5.6 vs. 40 ± 5.1 mm; p = .002). The LA-diameter was also a significant predictor for AF/AT recurrence after CB-PVI (odds ratio: 0.939, 95% confidence interval: [0.886, 0.992], p = .03). CONCLUSIONS: CB-PVI as index procedure for AF ablation resulted in favorable long-term outcome in symptomatic AF. CB-PVI might be recommended as interventional therapy in patients with lower LA remodeling.

First clinical experience using a visualized sheath for atrial fibrillation ablation.

INTRODUCTION: Recently, a novel steerable sheath allowing its real-time visualization within a 3D-mapping system was introduced to facilitate atrial fibrillation (AF) ablation. AIM: This study aimed to assess safety and efficacy of AF ablation using the visualized sheath and to compare its performance with a matched control group of patients who received ablation with conventional and non-visualized sheaths. METHODS: The study included consecutive patients between 09/2019 and 02/2021 who underwent routine AF ablation using the visualized sheath. Patients were regularly followed-up in our outpatient's clinic. Arrhythmia recurrence was defined as any atrial fibrillation (AF)/ atrial tachycardia (AT) episode lasting > 30 s after a blanking period of 3 months. RESULTS: A total number of 100 patients undergoing ablation using the visualized sheath were compared to a group of 99 matched patients. No major complications were observed. Total procedure duration (108 ± 22 min vs. 112 ± 12 min; p = 0.045), fluoroscopy time (7 ± 3 min vs. 10 ± 5 min; p < 0.001) and -dose (507 ± 501 cGy*cm2 vs. 783 ± 433 cGy*cm2 ; p < 0.001) were significantly lower using the visualized sheath. The benefit in terms of procedure duration was mainly driven by a shortened left atrial dwell time (73 ± 13 min vs. 79 ± 12 min; p = 0.001). During a mean follow-up of 12 months, the overall procedural success was 85% in the visualized sheath group versus 83% in the control group (p = 0.948). CONCLUSION: AF ablation using the novel visualized sheath is safe and effective and leads to a measurable decrease of procedure duration and radiation exposure. The integration of the novel sheath might help to further improve safety and efficacy of AF ablation.

Safety and acute efficacy of cryoballoon ablation for atrial fibrillation at community hospitals.

AIMS: Pulmonary vein isolation (PVI) using cryoballoon ablation (CBA) is an established procedure for treating symptomatic paroxysmal and persistent atrial fibrillation (AF). The safety and efficacy of PVI performed at community hospitals are unknown. We aimed to determine the safety and acute efficacy of PVI using CBA performed at community hospitals with limited annual case numbers. METHODS AND RESULTS: This registry study included 1004 consecutive patients who had PVI performed for symptomatic paroxysmal (n = 563) or persistent AF (n = 441) from January 2019 to September 2020 at 20 hospitals. Each hospital performed fewer than 100 CBA-PVI procedures/year according to local standards. Procedural data, efficacy, and complication rates were determined. The mean number of CBA procedures performed/year at each centre was 59 ± 25. The average procedure time was 90.1 ± 31.6 min and the average fluoroscopy time was 19.2 ± 11.4 min. Isolation of all pulmonary veins was documented in 97.9% of patients. The most frequent reason for not achieving complete isolation was development of phrenic nerve palsy. No hospital deaths were observed. Two patients (0.2%) suffered a clinical stroke. Pericardial effusion occurred in six patients (0.6%), two of whom (0.2%) required pericardial drainage. Vascular complications occurred in 24 patients (2.4%), two of whom (0.2%) required vascular surgery. Phrenic nerve palsy occurred in 48 patients (4.8%) and persisted up to hospital discharge in six patients (0.6%). CONCLUSION: Pulmonary vein isolation procedures for paroxysmal or persistent AF using CBA can be performed at community hospitals with high acute efficacy and low complication rates.

Cool enough? Lessons learned from cryoballoon-guided catheter ablation for atrial fibrillation in young adults.

INTRODUCTION: Cryoballoon (CB)-guided ablation of atrial fibrillation (AF) is established in symptomatic AF patients. This study sought to determine the safety and efficacy of CB pulmonary vein isolation (PVI) in young adults. METHODS AND RESULTS: A total of 93 consecutive patients aged <45 years referred to our center for AF ablation were included in this observational study. All patients received CB-guided PVI according to a standardized institutional protocol. Follow-up was performed in our outpatient clinic using 72-h Holter monitoring and periodic telephone interview. Recurrence was defined as any AF/atrial tachycardia (AT) episode >30 s following a 3-month blanking period. A propensity matched control group consisting of patients older than 45 years were used for further evaluation. Mean age was 35 ± 7 years, 22% suffered from persistent AF, 85% were male. Mean follow-up was 2.6 ± 2 years. At the end of the observational period, 83% of patients were free of any AF/AT episodes. There was an excellent overall 12-month success rate of 92%. In comparison to a matched group the overall recurrence rate was noticeably lower in the young group (15% vs. 27%). Increasing age was associated with a hazard ratio of 1.16 for recurrence. In a multivariate analysis model, left atrial diameter remained as significant predictor of AF/AT recurrence. The complication rate was low, no permanent phrenic nerve palsy was observed. CONCLUSION: CB-guided PVI in young adults is safe and effective with favorable long-term results. It may be considered as first-line therapy in this relatively healthy population.

Novel electroanatomical map for permanent his bundle pacing: the Mont Blanc approach - influence of the learning curve and procedural outcome.

AIMS: Pacing the specific conduction system like the Bundle of His (HB) can lead to more physiologic activation patterns compared to traditional right ventricular apical pacing. The aim of this study was to estimate the feasibility and value of electroanatomical mapping (EAM) for HB pacing during the learning curve and its impact on procedural outcome. METHODS AND RESULTS: Fifteen consecutive patients were treated using EAM of the His bundle region before implantation. Voltage and activation maps of HB potentials were performed. The activation time from His potential to R wave (ECG-reference) was measured and correlated to the HV interval. The atrial and ventricular potentials were blended so the active window could only see the His potential. After completing the activation map, it was transformed into a peak-to-peak voltage map of the HB. With reversed black and white colour scale, the exact point of the maximal His signal amplitude was visualized. Procedural data for the implantation were analysed using this innovative approach. The average total procedural time and fluoroscopy time was 88.2 ± 19.1 min and 10.9 ± 4.5 min, respectively. The 3D mapping time was 18.4 ± 5.1 min. The 13.9 ± 5.1 His potential points were needed in average to complete the map. No periprocedural complications were seen in this cohort. In 86.7% of cases, His bundle pacing was successful. The average threshold for the His bundle stimulation and the R-wave amplitude was 1.62 ± 1 V (@1.0 ms) and 4.8 ± 3.2 mV, respectively. The pacing impedance was 513.5 ± 102.8 Ω. Average paced QRS complex width was 116.9 ± 20.3ms. On average 2.6 ± 1.6 lead positions were targeted to find the optimal pacing site. CONCLUSION: Electroanatomical mapping-guided implantation of His-bundle leads can facilitate the identification of optimal pacing sites and allow to minimize procedure and fluoroscopy times even during the phase of the learning curve.

Prevention of ventricular fibrillation through de-networking of the Purkinje system: Proof-of-Concept Paper on the Substrate Modification of the Purkinje Network.

INTRODUCTION: Sudden cardiac death from ventricular fibrillation (VF) remains a major health problem worldwide. Currently, there are limited treatment options available to patients who suffer from episodes of VF. Because Purkinje fibers have been implicated as a source of initiation of VF, we are presenting the first paper of a series highlighting the promising results of substrate modulation through "De-Networking" of the Purkinje system preventing VF in patients without an alternative ablation strategy. METHODS AND RESULTS: We studied 10 consecutive patients (two female) all but one implanted with an ICD with documented VF or fast polymorphic Ventricular tachycardia (VT) (five patients without history of structural heart disease, two with ischemic cardiomyopathy, one with hypertrophic obstructive cardiomyopathy, one with dilated cardiomyopathy, and one with aortic valve disease). After 3D electroanatomical mapping, the left bundle branch (LBB) and left ventricular Purkinje potentials were annotated creating a virtual triangle with the apex formed by the distal LBB and the base by the most distal Purkinje potentials. Linear radiofrequency catheter ablation at the base of the triangle was performed, followed by ablation within the virtual triangle sparing the LBB and both fascicles ("de-networking"). All patients were treated without complications. During 1-year follow-up, only 2/10(20%) patients experienced recurrence in form of a single episode of polymorphic VT/VF. CONCLUSION: Catheter ablation of VF through "de-networking" of the Purkinje system in patients without overt arrhythmia substrate or trigger appears safe and effective and will require further study in a larger patient cohort.

Myocardial Bridge Complicated by Acute Myocardial Infarction.

Typically, myocardial bridging (MB) is considered a relatively benign condition; however, serious complications such as angina pectoris, myocardial infarction (MI), and sudden cardiac death may occur. The diagnosis and appropriate treatment of this pathology are important. We report a case of acute anterior wall ST-elevation MI occurring as a complication of MB involving the mid segment of the left anterior descending artery in a young, otherwise healthy woman who underwent a primary stenting procedure. Pathophysiologic mechanisms underlying the process leading from MB to acute MI vary, and so should the therapy for those patients. Coronary angiography, intravascular ultrasound, and, potentially, optical coherence tomography should be used to assist in establishing an accurate diagnosis in these complex patients and should guide the therapeutic decision in acute settings.

Anatomic Patterns of Renal Arterial Sympathetic Innervation: New Aspects for Renal Denervation.

AIMS: Initial studies of catheter-based renal arterial sympathetic denervation to lower blood pressure in resistant hypertensive patients renewed interest in the sympathetic nervous system's role in the pathogenesis of hypertension. However, the SYMPLICITY HTN-3 study failed to meet its prespecified blood pressure lowering efficacy endpoint. To date, only a limited number of studies have described the microanatomy of renal nerves, of which, only two involve humans. METHODS AND RESULTS: Renal arteries were harvested from 15 cadavers from the Klinikum Osnabruck and Schuchtermann Klinik, Bad Rothenfelde. Each artery was divided longitudinally in equal thirds (proximal, middle, and distal), with each section then divided into equal superior, inferior, anterior, and posterior quadrants, which were then stained. Segments containing no renal nerves were given a score value = 0, 1-2 nerves with diameter <300 µm a score = 1; 3-4 nerves or nerve diameter 300-599 µm a score = 2, and >4 nerves or nerve diameter ≥600 µm a score = 3. A total of 22 renal arteries (9 right-sided, 13 left-sided) were suitable for examination. Overall, 691 sections of 5 mm thickness were prepared. Right renal arteries had significantly higher mean innervation grade (1.56 ± 0.85) compared to left renal arteries (1.09 ± 0.87) (P < 0.001). Medial (1.30 ± 0.59) and distal (1.39 ± 0.62) innervation was higher than the proximal (1.17 ± 0.55) segments (p < 0.001). When divided in quadrants, the anterior (1.52 ± 0.96) and superior (1.71 ± 0.89) segments were more innervated compared to posterior (0.96 ± 0.72) and inferior (0.90 ± 0.68) segments (P < 0.001). CONCLUSIONS: That the right renal artery has significantly higher innervation scores than the left. The anterior and superior quadrants of the renal arteries scored higher in innervation than the posterior and inferior quadrants did. The distal third of the renal arteries are more innervated than the more proximal segments. These findings warrant further evaluation of the spatial innervation patterns of the renal artery in order to understand how it may enhance catheter-based renal arterial denervation procedural strategy and outcomes. CONDENSED ABSTRACT: The SYMPLICITY HTN-3 study dealt a blow to the idea of the catheter-based renal arterial sympathetic denervation. We investigated the location and patterns of periarterial renal nerves in cadaveric human renal arteries. To quantify the density of the renal nerves we created a novel innervation score. On average the right renal arteries were significantly more densely innervated than the left renal arteries, the anterior and superior segments were significantly more innervated compared to the posterior and inferior segments, absolute innervation scores in the proximal third of the left or right renal arteries were always lower when compared to distal segments. These findings may enhance catheter-based renal arterial denervation procedural strategy and outcomes.

Benefits of "Best for Groin" Strategy Leading to a Transapical TAVI Dominance.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) is a recognized therapeutic option for high-risk and inoperable patients with aortic valve stenosis. The choice of access route is a matter of debate. We are presenting our 5-year experience of transapical TAVI dominance. PATIENTS: This single-center study includes 575 patients. Two groups were compared: transapical (TA) and transfemoral (TF) with 454 and 121 patients, respectively. Individual access route decision was made by our heart team following a clinical and computed tomography (CT) data based nonbiased strategy. The same team performed all procedures. The mean logistic EuroSCORE was significantly higher in the TA group, however, without difference in STS score. The number of patients with coronary artery disease, previous cardiac surgery, and low left ventricular ejection fraction was higher in the TA group. There were no significant differences in age and presence of other comorbidities. RESULTS: Procedural success in both TA and TF groups was high (97.9% and 97.6%). No patient died during the procedure. Patient survival (30 days: TF, 97.5% vs. TA, 95.7%; 1 year: TF, 94.6% vs. TA, 81.8%; 2 years: TF, 84.7% vs. TA, 76.7%; 3 years: TF, 59.9% vs. TA, 67.8%) and a low TF vascular complication rate (1.6%) are encouraging compared with other registry data. CONCLUSION: A "no competition" team approach strategy along with an experienced hybrid team leads to fewer vascular complications and better outcomes for both TA and TF TAVI patients.

The ABC of a Simple Method for Pulmonary Vein Angiography.

Catheter-directed intervention to treat atrial fibrillation (AF) is becoming widely accepted procedure in current clinical practice. For assessment of pulmonary vein (PV) anatomy, angiography of left atrium (LA) and/or PV is often performed. We present a new, simple angiographic method for PVs and LA opacification using SL1 sheath. Total of 100 patients in our clinic underwent this procedure. In all of the cases good angiographic results were achieved. No immediate or late complications related to this procedure were observed.