Catheter-related and clinical complications associated with QDOT MICROTM Ablation Catheter.

INTRODUCTION: The QDOT MICROTM Ablation Catheter is a next-generation ablation catheter that allows for high-power ablation up to 90 watts. METHODS: We aimed to assess AE associated with the QDOT MICROTM catheter using the MAUDE database. A MAUDE database search was conducted on May 25, 2024, to capture all AEs (since FDA approval) associated with this ablation catheter. RESULTS: A total of 302 AEs from November 23, 2022, to April 30, 2024, were reported including 148 (49%) catheter-related issues and 154 (51%) clinical complications. Among the catheter-related issues, physical catheter damage (74.3%, n = 110) was most common, followed by communication or display issue (10.8%, n = 16), irrigation issue (9.5%, n = 14), signal issue or artifact (3.4%, n = 5), and inaccurate temperature measurement (2.0%, n = 3). Regarding clinical complications, the most common AE was pericardial effusion (43.5%, n = 67), followed by char formation (11.7%, n = 18), catheter thrombosis (7.1%, n = 11), stroke (7.1%, n = 11), pericarditis (7.1%, n = 11), esophageal complications (6.5%, n = 10), phrenic nerve palsy (3.9%, n = 6), cardiac arrest (3.9%, n = 6), significant AV block (3.9%, n = 6), pulmonary vein stenosis (3.2%, n = 5), coronary artery spasm (1.3%, n = 2), and pulmonary embolism (0.6%, n = 1). There were 11 deaths (five related to esophageal complications, five related to cardiac arrest, and one related to pericardial effusion with cardiac tamponade). CONCLUSION: As high-power ablation strategy with novel ablation catheters is becoming more widely utilized, operators must be aware of potential catheter-related issues and clinical complications that may arise. More data are needed to further evaluate risks of these complications to improve the catheter's safety and efficacy.

Adverse events associated with amplatzer left atrial appendage occlusion delivery system: A Food and Drug Administration MAUDE database study.

BACKGROUND: Dual occlusive closure mechanism (disc and lobe type), Amulet device (Abbott; a second-generation device that has replaced Amplatzer Cardiac Plug) was approved by the Food and Drug Administration (FDA) in August 2021 for percutaneous left atrial appendage occlusion (LAAO). However, real-world safety data on the delivery system (Amplatzer Cardiac Plug and Amplatzer Amulet device) are lacking. OBJECTIVE: We sought to assess the type of adverse events associated with the Amplatzer LAAO delivery system using the FDA Manufacturer and User Facility Device Experience (MAUDE) database. METHODS: A MAUDE database search was conducted on March 31, 2023, for reports received between February 2013 and March 2023 to capture all adverse events. RESULTS: A total of 59 adverse events were reported, of which 58 were sheath-related events, and one was a wire-related event. The most commonly encountered issue was air embolism (19%, 11 events), followed by sheath thrombosis (13.8%, eight events, two of which were also associated with device thrombosis), kinked sheath (10.3%, six events), and sheath deformation (8.6%, five events). Patient-related adverse events included pericardial effusion requiring pericardiocentesis (22.4%, 13 events), vascular complications (20.7%, 12 events), and device dislodgement (5.2%, three events). CONCLUSION: LAAO-related adverse events are increasingly being reported using the Amplatzer LAAO delivery sheath. It is anticipated that improvements in device technology, the advent of steerable sheaths, and operator experience will minimize these complications.

Clinical outcomes of radiofrequency catheter ablation of ventricular tachycardia in patients with hypertrophic cardiomyopathy.

BACKGROUND: Monomorphic ventricular tachycardia (VT) is rare in patients with hypertrophic cardiomyopathy (HCM), management of which is challenging. Limited data exists on the utility of catheter ablation for the treatment of VT in this population. OBJECTIVES: We aimed to assess clinical outcomes of catheter ablation for VT in HCM patients. METHODS: A systematic search, without language restriction, using PubMed, EMBASE, SCOPUS, Google Scholar, and ClinicalTrials.gov was performed. The meta-analysis was performed using a meta-package for R version 4.0/RStudio version 1.2 and Freeman Tukey double arcsine method to establish the variance of raw proportions. Outcomes measured included (1) acute procedure success (defined as noninducible for clinical VT), (2) freedom from VT at follow-up, (3) mortality. RESULTS: This systematic review of six studies (three from the United States and three from Japan) incorporated a total of 68 drug-refractory HCM patients who underwent VT radiofrequency catheter ablation (mean age 57.6 ± 13.3 years, mean LVEF 45.8 ± 15.4%, 85% men, maximum septal wall thickness 17.4 ± 4.6 mm, and 32.3% with an apical aneurysm). Acute procedural success was achieved in 84.5% patients (95% confidence interval [CI]: 70.6%-95.2%) with 27.9% patients had recurrent VT requiring multiple ablations (median 1, IQR 1-3). During the follow-up period (18.3 ± 11.7 months), the pooled incidence of freedom from recurrent VT after index procedure was 70.2% (95% CI: 51.9%-86.2%), while after the last ablation was 82.8% (95% CI: 57%-99.2%). There were two deaths during follow-up, one from heart failure and one from SCD 0.8% (95% CI: 0%-5.8%). CONCLUSION: The results of our pooled analysis demonstrated that catheter ablation for VT in HCM patients was associated with high acute procedural success, and reduced VT recurrence-findings comparable to previously published reports in other disease substrates.

Adverse events associated with AveirTM VR leadless pacemaker: A Food and Drug Administration MAUDE database study.

BACKGROUND: Leadless pacemaker (LP) offers an innovative approach for treating bradyarrhythmia, thus avoiding pacemaker pocket and lead-related complications. The Food and Drug Administration (FDA) has recently approved the Aveir™ leadless pacing system (screw-in type LP). METHODS: We queried the FDA MAUDE database to study the safety profile and assess the types of complications with this relatively novel device technology. A MAUDE database search was conducted on January 20, 2023, for reports received post-FDA approval to capture all adverse events. RESULTS: A total of 98 medical device report were reported for Aveir™ LP. After excluding duplicate, programmer-related, or introducer-sheath-related entries (n = 34), 64 entries were included. The most commonly encountered problem was high threshold/noncapture (28.1%, 18 events), followed by stretched helix (17.2%, 11 events) and device dislodgement (15.6%, ten events-5 intraprocedural, while 5 in the postoperative Day 1). Other reported events included high impedance (14.1%, nine events), sensing issues (12.5%, eight events), bent/broken helix (7.8%, five events), premature separation (4.7%, three events), interrogation problem (3.1%, two events), low impedance (3.1%, two events), premature battery depletion (1.6%, one event) and inadvertent MRI mode switch (1.6%, one event) and miscellaneous (15.6%, n = 10). There were eight serious patient injury events-pericardial effusion requiring pericardiocentesis (7.8%, five events) due to cardiac perforation that resulted in two deaths (3.1%) followed by sustained ventricular arrhythmias (4.6%, n = 3). CONCLUSION: In our study assessing the real-world safety profile of the Aveir™ LP, serious adverse events have been reported-life-threatening ventricular arrhythmias, pericardial effusion, device explantation/reimplantation, and death.

Intracardiac echocardiography from coronary sinus.

Intracardiac echocardiography (ICE) has become an essential tool and is an integral part of percutaneous interventional and electrophysiology (EP) procedures. Intracardiac echocardiography offers real-time, high-quality, near-field evaluation of cardiac anatomy. Standard ICE imaging includes placing the catheter in the right atrium (RA), right ventricle (RV), or left atrium (LA, via the transeptal approach). Coronary sinus echocardiography (CSE) is another alternative, where the ICE catheter is positioned in the coronary sinus (CS). This approach offers better catheter stability and allows operators to visualize cardiac structure with particularly excellent views of the LA, LAA, left ventricle (LV), and mitral annulus. Additionally, CSE is an attractive alternative in cases with unfavorable interatrial septum or fossa ovalis anatomical features that could lead to difficulty advancing ICE catheter in left atrium. In this article focusing on CSE, we provide illustration-based guidance to help operators identify critical cardiac structures from CSE.

Periprocedural outcomes of protamine administration after catheter ablation of atrial fibrillation.

BACKGROUND: Perioperative anticoagulation management with uninterrupted or minimally interrupted anticoagulation during atrial fibrillation (AF) ablation is thought to be critical to minimize thromboembolic complications. Protamine is often administered to neutralize the effects of heparin and expedite vascular hemostasis post-procedure. OBJECTIVE: We performed a systematic review and meta-analysis to determine the effectiveness of protamine to expedite vascular hemostasis and ambulation in patients undergoing AF ablation. METHODS: Electronic searches on PubMed, The Cochrane Library, EMBASE, EBSCO, Web of Science, and CINAHL databases from the inception through August 7, 2021, were performed. The primary outcomes included-time to hemostasis (minutes) and time to ambulation (minutes). The secondary outcomes included - any vascular complications (excluding minor hematoma), minor hematoma, or cerebrovascular accidents (CVA). RESULTS: A total of 5 eligible studies (3 retrospective cohort studies and two randomized trials) consisting of 1012 patients (515 patients received protamine group and 497 patients did not receive protamine group) were included in the meta-analysis. There was a significant reduction in time to ambulation [weighted mean difference (WMD) -176.6 minutes, 95% Confidence interval (CI) -266.9 to -86.3; p < 0.01] and time to hemostasis (WMD -13.72 minutes, 95% CI -22 to -5.4, p < 0.01) in the protamine group compared to the contrary. At a follow-up up to 3 months, there was no statistical difference between the two groups with regards to vascular complications (2.9% vs. 7.4%; Risk ratio (RR) 0.46 95% CI 0.17 to 1.24; p = 0.12), minor hematoma (2.1% vs. 5.8%; RR 0.43, 95% CI 0.16 to 1.2; p = 0.11) or CVA (0 vs. 0.3%; RR 0.62, 95% CI 0.08 to 4.98; p = 0.65). CONCLUSION: Protamine administration was associated with reduced time to ambulation (176 minutes reduction) and time to hemostasis (13 minutes reduction) without an increase in any adverse events.

Electromagnetic interference induced ventricular tachycardia in left ventricular assist device.

Left ventricular assist devices (LVAD) have been increasingly utilized end-stage heart failure despite guidelinedirected medical therapy (due to limited organ availability) as a bridge to transplant or destination therapy, with improved overall survival.Majority of patients undergoing LVAD implantation have pre-existing implantable cardioverter-defibrillator (ICD) in-situ.We present a case of device-device interaction resulting in EMI inducing recurrent inappropriate device therapies inducing ventricular arrhythmia followed by the inappropriate triggering of noise reversion mode, thereby inhibiting device therapies.With the increase in number of end-stage heart failure patients with ICDs in situ (and limited organ availability) undergoing LVAD implantation, it is imperative to recognize potential device-device interactions to avoid unwarranted invasive interventions.

Surgical left atrial appendage occlusion in patients with left ventricular assist device.

BACKGROUND: Thromboembolic (TE) events are among the most common and devastating adverse events in patients with continuous-flow left ventricular assist device (cf-LVAD). Given the high burden of AF among cf-LVAD patients, we sought to evaluate the effect of concomitant surgical LAAO in patients receiving cf-LVAD. METHODS: A systematic search using electronic databases was performed using the keywords: "left atrial appendage occlusion" and "left ventricular assist device." Statistical analysis was performed using metapackage for R version 4.0 and Rstudio version 1.2. Mantel-Haenszel risk ratio (RR) random-effects model was used to summarize data between two groups. The primary outcomes included: (a) stroke; (b) LVAD pump thrombosis; (c) all-cause mortality RESULTS: Three studies with a total of 305 patients (LAAO = 68 and No-LAAO = 237) were included in the analysis. HeartMate II (39%) and Heartware (27.5%) were the two most common cf-LVADs utilized, while only 5% received HeartMate III. At a mean follow up of 1.47 years, LAAO group had a lower risk of stroke (8.8% vs. 15.2%, RR 0.64; 95% CI 0.28-1.49), LVAD pump thrombosis (1.5% vs. 3.8%, RR 0.28; 95% CI 0.05-1.55) and all-cause mortality (5.9% vs. 20.2%, RR 0.69; 95% CI 0.19-2.52) when compared with no-LAAO group, but the difference did not reach statistical significance. CONCLUSION: Concomitant surgical LAAO at the time of cf-LVAD implantation demonstrated a trend toward positive outcomes and was not associated with adverse outcomes during the follow-up period, though the results were not statistically significant.

Early modified primary closure for treatment of cardiac implantable electronic device pocket infections.

BACKGROUND: Guidance for wound management of the vacated generator pocket in cardiac implantable electronic device (CIED) pocket infections after removal of all hardware and tissue debridement is limited. The typical surgical technique for management of a purulent wound is to allow healing by secondary intention. An alternative approach uses negative pressure wound therapy with or without delayed primary closure. While effective in managing infection, these approaches increase hospital length of stay and costs. We present our experience with a third option: modified early primary wound closure over a suction device. METHODS: All patients with CIED pocket infections who presented to our institution between September 2018 and October 2020 underwent extraction of hardware and modified primary wound closure over a negative pressure Jackson-Pratt drain. Length of hospital and postoperative stay, complications, and recurrent infections were recorded. RESULTS: During the study period, 14 patients underwent modified primary wound closure for CIED pocket infections. Mean length of hospital stay was 6.64 days ± 4.01 days (standard deviation [SD]). Mean postoperative length of stay was 3.92 ± 2.21 days (SD). Two patients (both on intravenous heparin for mechanical valve prostheses) required re-exploration for bleeding. No patients developed recurrent infection at a mean follow up of 363 ± 245 days (SD). CONCLUSION: Based on our experience, early modified primary wound closure for CIED pocket infections appears to be safe and allows for prompt discharge with no observed re-infections.

Biophysical parameters during radiofrequency catheter ablation of scar-mediated ventricular tachycardia: epicardial and endocardial applications via manual and magnetic navigation.

BACKGROUND: There is a paucity of data on biophysical parameters during radiofrequency ablation of scar-mediated ventricular tachycardia (VT). METHODS AND RESULTS: Data were collected from consecutive patients undergoing VT ablation with open-irrigation. Complete data were available for 372 lesions in 21 patients. The frequency of biophysical parameter changes were: >10Ω reduction (80%), bipolar EGM reduction (69%), while loss of capture was uncommon (32%). Unipolar injury current was seen in 72% of radiofrequency applications. Both EGM reduction and impedance drop were seen in 57% and a change in all 3 parameters was seen in only 20% of lesions. Late potentials were eliminated in 33%, reduced/modified in 56%, and remained after ablation in 11%. Epicardial lesions exhibited an impedance drop (90% vs. 76%, P = 0.002) and loss of capture (46% vs. 27%, P < 0.001) more frequently than endocardial lesions. Lesions delivered manually exhibited a >10Ω impedance drop (83% vs. 71%, P = 0.02) and an EGM reduction (71% vs. 40%, P < 0.001) more frequently than lesions applied using magnetic navigation, although loss of capture, elimination of LPs, and a change in all 3 parameters were similarly observed. CONCLUSIONS: VT ablation is inefficient as the majority of radiofrequency lesions do not achieve more than one targeted biophysical parameter. Only one-third of RF applications targeted at LPs result in complete elimination. Epicardial ablation within scar may be more effective than endocardial lesions, and lesions applied manually may be more effective than lesions applied using magnetic navigation. New technologies directed at identifying and optimizing ablation effectiveness in scar are clinically warranted.

New-generation electronic appliances and cardiac implantable electronic devices: a systematic literature review of mechanisms and in vivo studies.

INTRODUCTION: Cardiac implantable electronic device (CIED) functions are susceptible to electromagnetic interference (EMI) from electromagnetic fields (EMF). Data on EMI risks from new-generation electronic appliances (EA) are limited. OBJECTIVE: We performed a systematic literature review on the mechanisms of EMI, current evidence, and recently published trials evaluating the effect of EMF on CIEDs from electric vehicles (EV), smartphone, and smartwatch technology and summarize its safety data. METHODS: Electronic databases, including PubMed and EMBASE, were searched for in vivo studies evaluating EMF strength and incidence between CIEDs and commercial EVs, new-generation smartphones, and new-generation smartwatches. RESULTS: A total of ten studies (three on EVs, five on smartphones, one on smartphones, one on smartphones and smartwatches) were included in our systematic review. There was no report of EMI incidence associated with EVs or smartwatches. Magnet-containing smartphones (iPhone 12) can cause EMI when placed directly over CIEDs - thereby triggering the magnet mode; otherwise, no report of EMI was observed with other positions or smartphone models. CONCLUSION: Current evidence suggests CIED recipients are safe from general interaction with EVs/HEVs, smartphones, and smartwatches. Strictly, results may only be applied to commercial brands or models tested in the published studies. There is limited data on EMI risk from EVs wireless charging and smartphones with MagSafe technology.

Catheter ablation for atrial fibrillation in patients with prior left atrial appendage occlusion device.

BACKGROUND: The safety and efficacy of CA for AF and left-sided atrial arrhythmias (AA) in patients with left atrial appendage occlusion (LAAO) devices are lacking. METHODS: This is a single-center retrospective registry that included all patients with prior LAAO who underwent catheter ablation for AF or left-sided atrial arrhythmia from January 2020-January 2023. The primary outcomes were procedure-related complications, device-related complications, AA recurrence, and stroke. RESULTS: A total of 30 patients with prior LAAO were included in the analysis (mean age 75.1 ± 7.1 years old, 50% male, mean CHA2DS2-VASc score 4 ± 1.6, 46.7% paroxysmal AF, 73.3% had prior AF ablation, mean time to ablation 475 ± 365 days). 93.3% (n = 28) and 6.6% (n = 2) patients had ablation for AF (46.7% paroxysmal, 36.7% persistent, 10% long-standing persistent) and left-sided atrial tachycardia, respectively. 16.7% (n = 5) patients underwent ablation along the left atrial appendage ostium, and 3.3% (n = 1) underwent Vein of Marshall alcohol ablation. There were 3 (10%) peri-procedural complications (1 access hematoma and two pericardial effusions requiring intervention-none related to left atrial appendage ostium or alcohol ablation). During the mean follow-up of 440 ± 379 days, 40% (n = 12) patients had AA recurrence (91.6% AF, 8.3% atrial tachycardia), of which five patients needed repeat ablation, and two patients were readmitted for heart failure. There was no stroke or any device-related complications, including new peri-device leaks or device-related thrombosis in patients who had follow-up imaging studies (n = 11, 36.7%). CONCLUSION: Catheter ablation for AF (including VoM alcohol ablation) in patients with prior LAAO devices is feasible and safe with favorable outcomes.

Racial and Ethnic Disparities in Patients Who Underwent Leadless Pacemaker Implantation.

Evidence regarding racial disparities in leadless pacemaker (LP) utilization and outcomes is limited. We aimed to explore ethnicity-based disparities in LP utilization and clinical outcomes of patients who underwent LP implantation. All consecutive patients who underwent LP between January 2019 and January 2023 at our institution were included. Charts were reviewed for baseline characteristics and clinical outcomes. The primary outcomes were procedure-related complications, cardiac rehospitalization, worsening heart failure (HF) or HF hospitalization, and all-cause mortality. All statistical analyses were performed using SPSS Statistics 22 (IBM Corp., Armonk, NY). The p <0.05 was considered statistically significant. A total of 196 adult patients underwent LP implantation during the study period (48% Caucasians, 36.2% Hispanic, 8.2% Asians, and 7.7% African-American). The groups were balanced with respect to baseline demographics, clinical characteristics, and procedure-related complications. During the median follow-up of 104 days (interquartile range 24 to 382), no statistically significant differences were observed in worsening HF or HF hospitalization or all-cause mortality among the ethnic groups. After multivariable logistic regression, Asian individuals had higher odds of cardiac readmissions (odds ratio 4.1, 95% confidence interval 1.4 to 12.3, p = 0.01). Patients from racial and ethnic minorities face significant inequities in arrhythmia care, including patients who have undergone LP implantation. Awareness and a system-based approach (understanding cultural preferences, effective application of evidence-based guidelines, and population-based policies) are crucial to lessen disparities in health care among minorities.

Conduction system pacing in prosthetic heart valves.

BACKGROUND: There has been increasing interest in physiologic pacing techniques that directly activate the specialized conduction system. We aimed to assess outcomes of conduction system pacing (CSP) in patients with prosthetic heart valves. METHODS: This systematic review was performed according to PRISMA guidelines. Freeman-Tukey double arcsine transformation with the random-effect model was used to summarize the data. Outcomes studied were 1) implant success (defined as ability to recruit the His-Purkinje system or the distal Purkinje system); (2) lead parameters at implant and follow-up; and (3) procedure-related complications. RESULTS: This systematic review of 7 studies included 267 unique patients in whom CSP was attempted with either HBP or LBBAP for pacing indications after a prosthetic valve. HBP was attempted in 38% (n = 108), while LBBAP in 62% (n = 175) patients. The overall success rate of CSP was 87%, while in patients post-TAVR, the overall success rate was 83.2%. In the subgroup analysis, LBBAP had a significant higher overall success rate compared to HBP (94.3% vs. 76.5%, p interaction = 0.02) and post-TAVR patients (94.3 vs. 66.9%, p interaction < 0.01), respectively. The LBBAP thresholds were significantly lower compared to HBP both at implant (0.67 ± 0.4 @ 0.44 ms vs. 1.35 ± 1 @ 0.85 ms, p interaction < 0.01) and at a mean follow-up of 12.4 ± 8 months (0.73 ± 0.1 @ 0.44 ms vs. 1.39 ± 1 @ 0.85 ms, p interaction < 0.01), respectively. CONCLUSION: CSP is safe and feasible in patients with a prosthetic valve, with a significantly higher success rate and superior lead parameters with LBBAP than HBP, especially in patients post-TAVR.

Catheter ablation of typical atrial flutter in severe pulmonary hypertension.

BACKGROUND: Radiofrequency ablation is first-line therapy for atrial flutter (AFL). There are no studies of ablation in patients with severe pulmonary arterial hypertension (PAH). METHODS: Consecutive patients with severe PAH (systolic pulmonary artery pressure >60 mmHg) and AFL referred for ablation were evaluated. Patients with complex congenital heart disease were excluded. RESULTS: A total of 14 AFL ablation procedures were undertaken in 12 patients. A total of 75% of patients were female; mean age 49 ± 12 years. SPAP prior to ablation was 99 ± 35 mmHg. Baseline 6-minute walk distance was 295 ± 118 m. ECG demonstrated a typical AFL pattern in only 42% of cases. Baseline AFL cycle length was longer in PAH patients compared to controls (295 ± 53 ms vs 252 ± 35 ms, P = 0.006). Cavotricuspid isthmus dependence was verified in 86% of cases. Acute success was obtained in 86% of procedures. SPAP decreased from 114 ± 44 mmHg to 82 ± 38 mmHg after ablation (P = 0.004). BNP levels were lower postablation (787 ± 832 pg/mL vs 522 ± 745 pg/mL, P = 0.02). Complications were seen in 14%. A total of 80% (8/10) of patients were free of AFL at 3 months; 75% (6/8) at 1 year. CONCLUSION: Ablation of AFL in severe PAH patients is feasible, with good short- and intermediate-term success rates. The ECG pattern is not a reliable marker of isthmus dependence. The SPAP and BNP levels may decrease postablation. AFL may be a marker of poor outcomes in patients with PAH with a 1-year mortality rate of 42% in this study. This rate is higher than expected in the general PAH population.

Catheter ablation utilizing remote magnetic navigation: a review of applications and outcomes.

The utilization of the NIOBE™ magnetic navigation system (MNS, Stereotaxis, St. Louis, MO, USA) has increased significantly since the first published report in 2002. There has been much enthusiasm for this technology as a means to reduce radiation exposure to the patient and physician alike, and potentially decrease risks associated with catheter manipulation by less experienced operators. However, there are limited data regarding the acute, intermediate, and long-term results and procedural characteristics from ablation procedures utilizing this system. We present a review of the outcomes and procedural data available to date.

Restricting sports for athletes with heart disease: are we saving lives, avoiding lawsuits, or just promoting obesity and sedentary living?

Sudden cardiac death in young competitive athletes is tragic and usually due to unsuspected cardiovascular disease. Screening programs for athletes remain debatable, and restriction of athletes from sports can have physical, emotional, and legal ramifications. In this article, we review the epidemiology of the more common inherited arrhythmias and congenital heart diseases that are of concern in a newly diagnosed athlete. A comparison of the current American Heart Association/American College of Cardiology and European Society guidelines, which are primarily based on expert opinion due to lack of randomized studies, is then undertaken. Furthermore, certain legal repercussions associated with both qualifying and restricting athletes from competitive sports are discussed. Lastly, we urge physicians to keep in mind that disqualifying an athlete from competitive sports does not mean restriction of all activities, and even patients with inherited arrhythmias and congenital heart disease can participate in low to moderate activity complementary with a healthy lifestyle.

The emerging role of cardiac resynchronization therapy in milder heart failure: are we implanting too late for response?

The role of cardiac resynchronization therapy in mild heart failure has become a focus of attention with the publication of recent clinical trials. We present a review of the data supporting implantation of cardiac resynchronization devices in early stage heart failure. In addition, we present evidence that may suggest patients are often implanted too late for clinical benefit, potentially contributing to the relatively high nonresponder rate seen in randomized trials and clinical practice.

Ablation of Post Transplant Atrial Flutter and Pseudo-fibrillation Using Magnetic Navigation via a Superior Approach.

Ablation of cavotricuspid ishtmus flutter and atrial tachycardia in a complex substrate has never been reported using remote navigation via superior approach. Venous access was obtained via right internal jugular for ablation and left subclavian for duodecapolar catheter placement into the coronary sinus. In a posttransplant patient presenting with both regular and irregular tachycardia, both cavotricuspid isthmus flutter in the donor and atrial tachycardia in the recipient was mapped using a two catheter approach. Successful ablation of typical atrial flutter and anastomotic block was achieved. This is the first report of successful ablation of cavotricuspid isthmus flutter and posttransplant atrial tachycardia using magnetic navigation via superior approach. Using only two catheters, this approach is logical and feasible in complex substrates with interrupted inferior venous access.