Impact of SGLT2 Inhibitors on AF Recurrence After Catheter Ablation in Patients With Type 2 Diabetes.

BACKGROUND: The effects of sodium-glucose cotransporter 2 inhibitors (SGLT2-Is) on recurrent atrial fibrillation (AF) among patients undergoing catheter ablation is not well described. OBJECTIVES: This study sought to assess the impact of SGLT2-Is on the recurrence of AF among patients with type 2 diabetes mellitus (DM) after catheter ablation. METHODS: Using the TriNetX research network, we identified, by means of Current Procedural Terminology codes, patients ≥18 years of age with type 2 diabetes mellitus (DM) who had undergone AF ablation from April 1, 2014, to November 30, 2021. Patients were stratified based on the baseline SGLT2-I use. Propensity-score matching resulted in 2,225 patients in each cohort. The primary outcome was a composite of cardioversion, new antiarrhythmic drug (AAD) therapy, or re-do AF ablation after a blanking period after the index ablation. Additional outcomes included heart failure exacerbations, ischemic stroke, all-cause hospitalization, and death during 12 months of follow-up. RESULTS: SGLT2-I use in patients with type 2 DM undergoing AF ablation was associated with a significantly lower risk of cardioversion, new AAD therapy, and re-do AF ablation (adjusted OR: 0.68; 95% CI: 0.602-0.776; P < 0.0001). At 12 months, patients on SGLT2-Is had a higher probability of event-free survival (HR: 0.85, 95% CI: 0.77-0.95; log-rank test chi-square = 8.7; P = 0.003). All secondary outcomes were lower in the SGLT2I group; however, the ischemic stroke did not differ between groups. CONCLUSIONS: Use of SGLT2-Is in patients with type 2 DM is associated with a lower risk of arrhythmia recurrence after AF ablation and thence a reduced need for cardioversion, AAD therapy, or re-do AF ablation.

Utilization Trends In Platelet Adenosine Diphosphate P2Y12 Receptor Inhibitor and Cost Among Medicare Beneficiaries.

Recent guidelines regarding acute coronary syndrome (ACS) have advocated for use of prasugrel and ticagrelor over clopidogrel for acute coronary syndrome. However, analyses from multiple databases have shown that clopidogrel continues to be the most commonly prescribed P2Y12 inhibitor. We aimed to evaluate the trends in utilization and cost of P2Y12 inhibitors for Medicare beneficiaries using data from Medicare Part D Prescription Drug Data Event set from 2011 to 2018 for P2Y12 inhibitors. Medicare part D total beneficiaries for P2Y12 receptor inhibitors increased from 2011 to 2018 by 34.8% from 2.45 million to 3.31 million. The total cost for P2Y12 antiplatelets decreased from $ 3.72 billion in 2011 to $ 0.72 billion in 2018 by 80.4%. The availability of generic clopidogrel drove the considerable total cost reduction. Clopidogrel was the most prescribed P2Y12 inhibitor since its introduction accounting for more than 90% of the Medicare beneficiaries from 2013 to 2018. Overall, the number of beneficiaries on newer P2Y12 inhibitors showed a steady increase with 5.9% beneficiaries on brilinta in 2018 and 2.1 % on prasugrel. The total cost of brilinta beneficiaries grew exponentially accounting for 59.2% of total cost in 2018 and average cost per beneficiary increased by 465% in study period. Despite the availability of generic version clopidogrel and prasugrel, 2,161,175 beneficiaries were on brand plavix and 87,174 on effient which contributed to the increased total expenditure. Earlier introduction and transition to generic versions of medication may help to reduce the drug cost and potentially enhance medication compliance.

A Blast From the Past: Radiation Therapy During Childhood Causing Cardiac Fibrosis and Calcification Leading to Complete Heart Block.

Complete heart block (CHB) in a young patient is a rare phenomenon necessitating an extensive workup to identify the etiology of conduction disturbance. Radiotherapy of the thorax is a known risk factor for cardiomyopathy; however, CHB is a rare complication. Here we present a case of a 46-year-old man who presented with CHB and was found to have significant cardiac fibrosis and calcification of the mitral valve annulus. His management required a multidisciplinary and multimodality approach to be able to identify childhood radiation as the cause of cardiomyopathy and establish a personalized management strategy with cardiac resynchronization therapy defibrillator. This case highlights radiation therapy as an important cause of cardiac conduction abnormalities even decades later, and the importance of extensive search for other reversible etiologies using the multimodality approach.

Initial Experience with High-density Mapping of Ischemic Ventricular Tachycardia Using a Narrow 0.1-mV to 0.25-mV Border-zone Window.

This study sought to determine (1) whether the use of a narrow border-zone voltage of 0.1 to 0.25 mV predicts the ventricular tachycardia (VT) exit site better than when using the conventional 0.5 to 1.5 mV window and (2) the feasibility of utilizing the Rhythmia mapping system (Boston Scientific, Natick, MA, USA) to map hemodynamically unstable VT without hemodynamic support. The Ablation of ischemic VT is challenging especially in the setting of hemodynamic instability, yet efficient and accurate mapping of VT and VT substrate is critical for procedural success. In this study, a total of 24 patients with ischemic cardiomyopathy and recurrent monomorphic VT underwent mapping and ablation using the Rhythmia system. Contact-force sensing ablation catheters were use in two cases. In patients with mappable VTs, the distance between the exit site and border zone was calculated for border zone-voltage windows of 0.5 to 1.5 mV and 0.1 to 0.25 mV. The percentage of LV scar for each patient was visually estimated into quartiles of scar burden in both windows. Twenty patients were inducible into VT, while 15 patients had mappable VTs for a total of 16 VTs (11 stable VTs and five unstable VTs). There were no adverse complications in patients who underwent mapping in unstable VT. The mean distance from the VT exit site to the border zone was 13.3 mm in the conventional window and 3.4 mm in the narrow window (95% confidence interval: 4.0-15.8; p = 0.003). Separately, 94% (15/16) of the VTs were mapped to the narrow border-zone voltage versus 31% (5/16) using the conventional border zone (p = 0.0006). The use of a narrow 0.1- to 0.25-mV border-zone window highlights relevant scar and constitutes a border zone where VT exit sites are frequently located. We also found that exit sites of hemodynamically unstable VTs can be identified without an increase in procedural complications using the Orion catheter (Boston Scientific, Natick, MA, USA).

Bradycardia, Hypotension, and Cardiac Arrest: A Complication of Local Anesthetics.

Local anesthetics are routinely used in the field of medicine during many procedures, to alleviate acute pain. Although they are relatively safe, they have the ability to produce undesirable neurotoxic and cardiotoxic symptoms when administered intravascularly. Examples of cardiotoxicity include myocardial depression, cardiac arrhythmias, and cardiovascular collapse. The case below describes the adverse events of severe bradycardia, PR prolongation with subsequent heart block, and sinus arrest following an elective knee replacement in a 73-year-old male who received bupivacaine and ropivacaine.

Atrial Substrate and Triggers of Paroxysmal Atrial Fibrillation in Patients With Obstructive Sleep Apnea.

BACKGROUND: Obstructive sleep apnea (OSA) is associated with atrial remodeling, atrial fibrillation (AF), and increased incidence of arrhythmia recurrence after pulmonary vein (PV) isolation. We aimed to characterize the atrial substrate, including AF triggers in patients with paroxysmal AF and OSA. METHODS AND RESULTS: In 86 patients with paroxysmal AF (43 with ≥moderate OSA [apnea-hypopnea index ≥15] and 43 without OSA [apnea-hypopnea index <5]), right atrial and left atrial voltage distribution, conduction velocities, and electrogram characteristics were analyzed during atrial pacing. AF triggers were examined before and after PV isolation and targeted for ablation. Patients with OSA had lower atrial voltage amplitude (right atrial, P=0.0005; left atrial, P=0.0001), slower conduction velocities (right atrial, P=0.02; left atrial, P=0.0002), and higher prevalence of electrogram fractionation (P=0.0001). The areas of atrial abnormality were consistent among patients, most commonly involving the left atrial septum (32/43; 74.4%). At baseline, the PVs were the most frequent triggers for AF in both groups; however, after PV isolation patients with OSA had increased incidence of additional extra-PV triggers (41.8% versus 11.6%; P=0.003). The 1-year arrhythmia-free survival was similar between patients with and without OSA (83.7% and 81.4%, respectively; P=0.59). In comparison, control patients with paroxysmal AF and OSA who underwent PV isolation alone without ablation on extra-PV triggers had increased risk of arrhythmia recurrence (83.7% versus 64.0%; P=0.003). CONCLUSIONS: OSA is associated with structural and functional atrial remodeling and increased incidence of extra-PV triggers. Elimination of these triggers resulted in improved arrhythmia-free survival.

Comparison of Standard Catheters Versus Radial Artery-Specific Catheter in Patients Who Underwent Coronary Angiography Through Transradial Access.

In this prospective, randomized controlled study, we aim to compare the performance outcomes of standard catheters with the radial artery-specific catheter. Over the past decade, transradial cardiac catheterization has gained widespread popularity because of its low complication rates compared with transfemoral access. Operators have the choice of using either standard catheters (used for both transfemoral and transradial approach, with need for separate catheter use for either right or left coronary artery engagement) or a dedicated radial artery catheter, which is specifically designed to engage both coronary arteries through radial artery access. A total of 110 consecutive patients who underwent coronary angiography at our institution from March 2015 to April 2015 were prospectively randomized to either radial artery-specific Tiger catheter (5Fr; Terumo Interventional Systems, Somerset, New Jersey) versus standard Judkins left and right catheters (5Fr R4, L4; Cordis Corporation, Miami, Florida). The end points of the study included fluoroscopy time, dose-area product, contrast volume used, and total procedure time for the coronary angiography. A total of 57 patients (52%) were randomized to radial artery-specific catheter and 53 (48%) to the standard catheter. Tiger catheter was associated with significantly lower fluoroscopy time (184 ± 91 vs 238 ± 131 seconds, p = 0.015), which was statistically significant. Other outcome measures such as dose-area product (2,882.4 ± 1,471.2 vs 3,524.6 ± 2,111.7 Gy·cm(2), p = 0.07), total contrast volume (48.1 ± 16.1 vs 53.4 ± 18.5 ml, p = 0.114), and total procedure time (337 ± 382 vs 434 ± 137 seconds, p = 0.085) were also lower in single-catheter group, but it did not reach statistical significance. A total of 8 patients (14%) were crossed over from radial-specific catheter arm to standard catheter arm because of substandard image quality and difficulty in coronary engagement. Six patients had to be switched to femoral access (3 in each group) secondary to radial artery spasm. In conclusion, the radial artery-specific catheter was shown to have significantly lower fluoroscopy times but higher failure rates compared with the standard catheters.

A new trick to a routine procedure: taking the fear out of the axillary vein stick using the 35° caudal view.

AIMS: The axillary vein is frequently used to implant pacemaker and defibrillator leads. We describe a technique utilizing the caudal fluoroscopic view to facilitate axillary venous access without contrast. METHODS AND RESULTS: Outcomes of device implants or upgrades utilizing this technique were examined during a 1-year period at our institution. Of 229 consecutive implants, only 9 patients required an alternate technique for lead implantation. There were zero cases of pneumothorax. CONCLUSIONS: The caudal view allows for optimal appreciation of the anterior border of the lung and the first rib. This simple technique increases the implanter's appreciation of and control over the access needle depth relative to the lung and first rib, thereby reducing pneumothorax risk.

Imaging Modalities to Identity Inflammation in an Atherosclerotic Plaque.

Atherosclerosis is a chronic, progressive, multifocal arterial wall disease caused by local and systemic inflammation responsible for major cardiovascular complications such as myocardial infarction and stroke. With the recent understanding that vulnerable plaque erosion and rupture, with subsequent thrombosis, rather than luminal stenosis, is the underlying cause of acute ischemic events, there has been a shift of focus to understand the mechanisms that make an atherosclerotic plaque unstable or vulnerable to rupture. The presence of inflammation in the atherosclerotic plaque has been considered as one of the initial events which convert a stable plaque into an unstable and vulnerable plaque. This paper systemically reviews the noninvasive and invasive imaging modalities that are currently available to detect this inflammatory process, at least in the intermediate stages, and discusses the ongoing studies that will help us to better understand and identify it at the molecular level.