The Zero Calcium Score Paradox

Our study presents a case of angina with a zero calcium score yet severe coronary stenosis from noncalcified plaque. We highlight the limitation of otherwise prognostically powerful coronary calcium score as a singular predictive tool especially when used in symptomatic patients.

Bilateral Cardiac Sympathetic Denervation for Refractory Multifocal Premature Ventricular Contractions in Patients With Nonischemic Cardiomyopathy

BACKGROUND

Bilateral cardiac sympathetic denervation (BCSD) for refractory life-threatening ventricular arrhythmias is a neuromodulatory intervention targeting sympathetically driven focal or re-entrant ventricular arrhythmias.

OBJECTIVES

This study sought to provide a more complete and successful option for intervention in patients in whom premature ventricular contraction (PVC) ablation is not feasible or has been unsuccessful.

METHODS

A total of 43 patients with >5% PVC burden and concomitant nonischemic cardiomyopathy (NICM) who previously failed medical and ablation therapies were referred for BCSD. All patients underwent bilateral video-assisted thoracoscopic surgical approach with T1-T4 sympathectomy. Primary effectiveness endpoints were postprocedural PVC burden resolution, improvement in left ventricular ejection fraction (LVEF), and cessation of antiarrhythmic drugs (AADs). Safety endpoints included peri- and postprocedural complications. Outcomes were assessed over a 1-year follow-up period.

RESULTS

Among the 43 patients who underwent BCSD, the mean age was 52.3 ± 14.7 years, 69.8% of whom were male patients. Presenting mean LVEF was 38.7% ± 7.8%, and PVC burden was 23.7% ± 9.9%. There were significant reductions in PVC burden postprocedurally (1.3% ± 1.1% post-BCSD, compared with 23.7% ± 9.9% pre-BCSD, P < 0.001) and improvements in LVEF (46.3% ± 9.5% post-BCSD, compared with 38.7% ± 7.8% pre-BCSD, P < 0.001). The rate of ICD therapies decreased from 81.4% (n = 35) to 11.6% (n = 5) (P < 0.001), leading to a significant reduction in use of AADs (100.0% to 11.6%, P < 0.001) and improvement in mean NYHA functional class (2.5 ± 0.5 to 1.4 ± 0.2, P < 0.001). Major intraoperative complications were seen in 4.7% of patients (hemothorax and chylothorax). Of the patients, 81.4% (n = 35) experienced no mortality or major complications over a 1-year follow-up period, with the remaining still within their first year postprocedure.

CONCLUSIONS

BCSD is effective for the management of refractory PVCs and ventricular tachycardia who have failed previous ablation therapy.

A Rare Case of New-Onset Atrial Fibrillation Presenting as Biatrial Inflammation Seen on 18F-FDG-PET

Isolated atrial myocarditis, a rare clinical entity, is presented in this case report as the diagnosis in a patient with new-onset atrial fibrillation. Our findings emphasize the potential for atrial arrhythmias and their unusual presentation; the role of multimodal imaging, especially 18F-FDG-PET/CT, in diagnosis; and considerations for long-term treatment strategies.

Left Atrial Appendage Closure with Watchman vs Amulet Devices: Similarities and Differences

PURPOSE OF REVIEW

Left atrial appendage closure (LAAC) has shown to be non-inferior to oral anticoagulation (OAC) for non-valvular atrial fibrillation (AF). LAAC is now becoming a leading method for stroke prophylaxis in patients who have atrial fibrillation and are unable to tolerate OAC. There are currently two FDA-approved endocardial closure devices, namely, the Watchman FLX and Amplatzer Amulet.

RECENT FINDINGS

Current data highlights that both devices offer similar efficacy and safety for LAAC. While the two devices differ in terms of intraprocedural complication rates, they offer similar short- to long-term outcomes in regard to peri-device leaks, device-related thrombosis, and mortality. With similar risk and safety profiles, both devices are indicated for patients who are unable to tolerate OAC. Newer clinical studies are directed to establish the efficacy of both devices as the primary method for stroke prevention in AF as an alternate to OAC.

Lower-adherence direct oral anticoagulant use is associated with increased risk of thromboembolic events than warfarin

BACKGROUND

Real-world data have suggested inconsistent adherence to oral anticoagulation for thromboembolic event (TE) prevention in patients with Non valvular atrial fibrillation (NVAF), yet it remains unclear if event risk is elevated during gaps of non-adherence.

OBJECTIVE

To compare difference in outcomes between direct oral anticoagulant (DOAC) and warfarin based on adherence to the therapy in patients with NVAF.

METHODS

Using the MarketScan claims data, patients receiving prescription of warfarin or a DOAC for NVAF from January 2015 to June 2016 were included. Outcomes included hospitalization for TE (ischemic stroke or systemic embolism), hemorrhagic stroke, stroke of any kind, and major bleeding. Event rates were reported for warfarin and DOACs at a higher-adherence proportion of days covered (PDC > 80%) and lower-adherence (PDC 40-80%).

RESULTS

The cohort included 83,168 patients prescribed warfarin (51% [n = 42,639]) or DOAC (49% [n = 40,529]). Lower adherence occurred in 36% (n = 15,330) of patients prescribed warfarin and 26% (n = 10,956) prescribed DOAC. As compared to higher-adherence warfarin after multivariable adjustment, the risk of TE was highest in lower-adherence DOAC (HR 1.26; 95% CI, 1.14-1.33), and lowest in higher-adherence DOAC (HR, 0.93; 95% CI, 0.88-0.99). There was a significantly higher risk of hemorrhagic stroke and stroke of any kind in the lower-adherence groups. Major bleeding was more common with lower-adherence DOAC (HR, 1.43, 95% CI, 1.35-1.52) and lower-adherence warfarin (HR, 1.32, 95% CI, 1.26-1.39).

CONCLUSIONS

In this large real-world study, low adherence DOAC was associated with higher risk of TE events as compared to high and low adherence warfarin.

Long-Term Imaging and Clinical Outcomes of Surgical Left Atrial Appendage Occlusion With AtriClip

Surgical left atrial appendage (LAA) occlusion with an AtriClip (AtriCure, West Chester, Ohio) is frequently performed for stroke prophylaxis in patients with atrial fibrillation (AF). We conducted a retrospective analysis of all patients with long-standing persistent AF who underwent hybrid convergent ablation and LAA clipping. Contrast-enhanced cardiac computed tomography was performed at 3 to 6 months after LAA clipping to assess the degree of complete closure and the residual LAA stump. A total of 78 patients (64 ± 10 years, 72% male) underwent LAA clipping as part of hybrid convergent AF ablation, from 2019 to 2020. Median size of AtriClip used was 45 mm. Mean LA size was 4.6 ± 1 cm. At 3-to-6 months follow-up computed tomography, 46.2% of patients (n = 36) had a residual stump proximal to the deployed LAA clip. Mean depth of residual stump was 3.95 ± 5.5 mm, with 19% of patients (n = 15) having a stump depth of ≥10 mm and 1 patient requiring more endocardial LAA closure owing to large stump depth. During 1-year follow-up, 3 patients developed stroke; device leak of 6 mm was noted in 1 patient; and none of the patients had a thrombus proximal to the clip. In conclusion, high incidence of residual LAA stump was observed with AtriClip. Larger studies with long-term follow-up are needed to better assess the thromboembolic implications of a residual stump after AtriClip placement.

Data deluge from remote monitoring of cardiac implantable electronic devices and importance of clinical stratification

Background

Remote monitoring (RM) has been accepted as a standard of care for follow-up of patients with cardiac implantable electronic devices (CIEDs). However, the resulting data deluge poses major challenge to device clinics.

Objective

This study aimed to quantify the data deluge from CIED and stratify these data based on clinical relevance.

Methods

The study included patients from 67 device clinics across the United States being remotely monitored by Octagos Health. The CIEDs included implantable loop recorders, pacemakers, implantable cardioverter-defibrillators, cardiac resynchronization therapy defibrillators, and cardiac resynchronization therapy pacemakers. Transmissions were either dismissed before reaching the clinical practice if they were repetitive or redundant or were forwarded if they were either clinically relevant or actionable transmission (alert). The alerts were further classified as level 1, 2, or 3 based on clinical urgency.

Results

A total of 32,721 patients with CIEDs were included. There were 14,465 (44.2%) patients with pacemakers, 8381 (25.6%) with implantable loop recorders, 5351 (16.4%) with implantable cardioverter-defibrillators, 3531 (10.8%) with cardiac resynchronization therapy defibrillators, and 993 (3%) with cardiac resynchronization therapy pacemakers. Over a period of 2 years of RM, 384,796 transmissions were received. Of these, 220,049 (57%) transmissions were dismissed, as they were either redundant or repetitive. Only 164,747 (43%) transmissions were transmitted to the clinicians, of which only 13% (n = 50,440) had clinical alerts, while 30.6% (n = 114,307) were routine transmissions.

Conclusion

Our study shows that data deluge from RM of CIEDs can be streamlined by utilization of appropriate screening strategies that will enhance efficiency of device clinics and provide better patient care.

Feasibility and Safety of Intravenous Sotalol Loading in Adult Patients With Atrial Fibrillation (DASH-AF)

BACKGROUND

Inpatient initiation of sotalol is recommended owing to its proarrhythmic effects. The DASH-AF (Feasibility and Safety of Intravenous Sotalol Administered as a Loading Dose to Initiate Oral Sotalol Therapy in Adult Patients With Atrial Fibrillation) trial evaluates the safety and feasibility of intravenous (IV) sotalol, achieving a steady state with maximum QTc prolongation within 6 hours instead of the traditional 5-dose inpatient oral (PO) titration.

METHODS

DASH-AF is a prospective, nonrandomized, multicenter, open-label trial consisting of patients who underwent IV sotalol loading dose to initiate rapid oral therapy for atrial arrhythmias. IV dose was calculated based on the target oral dose as indicated by baseline QTc and renal function. Patients' QTc (in sinus) was measured via electrocardiography at 15-minute intervals and after IV loading completion. Patients were discharged 4 hours after first oral dose. All patients were monitored via mobile cardiac outpatient telemetry for 72 hours. The control group was composed of patients admitted for the traditional 5 PO doses. Safety outcomes were assessed in both groups.

RESULTS

One hundred twenty patients from 3 centers were enrolled from 2021 to 2022 in the IV loading group (compared with type of AF- and renal function-matched patients in the conventional PO loading cohort). This study demonstrated no significant change in ΔQTc in both groups, with a significantly lower number of patients requiring dose adjustment in the IV arm compared with the PO arm (4.1% vs 16.6%; P = 0.003). This led to potential cost savings of up to $3,500.68 per admission.

CONCLUSIONS

The DASH-AF trial shows that rapid IV sotalol loading in atrial fibrillation/flutter patients for rhythm control is feasible and safe compared with conventional oral loading with significant cost reduction. (Feasibility and Safety of Intravenous Sotalol Administered as a Loading Dose to Initiate Oral Sotalol Therapy in Adult Patients With Atrial Fibrillation [DASH-AF]; NCT04473807).

Residual leak following left atrial appendage occlusion with lariat closed with amplatzer pfo occluder device

Leaks from incomplete ligation of the left atrial appendage (LAA) following closure with Lariat device are not uncommon and associated with higher stroke rate. This clinical vignette highlights a procedure of closure of residual leak following closure with Lariat device with Amplatzer Talisman PFO Occluder. This article is protected by copyright. All rights reserved.

Low Left Atrial Appendage Emptying Velocity is a Predictor of Atrial Fibrillation Recurrence After Catheter Ablation

BACKGROUND

Recurrence of atrial fibrillation (AF) after catheter ablation (CA) remains common and studies have shown about 5%-9% annual recurrence rate after CA. We sought to assess the echocardiogram derived left atrial appendage (LAA) emptying velocity as a predictor of AF recurrence after CA.

OBJECTIVE

To determine if LAA emptying is a marker of recurrence of AF post-CA METHODS: A total of 303 consecutive patients who underwent CA for AF between 2014 and 2020 were included. Baseline clinical characteristics and echocardiographic data of the patients were obtained by chart review. LAA emptying velocities were obtained from TEE. LA voltage was obtained during the mapping for CA. Chi-square test and nominal logistic regression were used for statistical analysis. An ROC curve was used to determine LAA velocity cut-off.

RESULTS

Mean patient age was 61.7±10.5; 32% were female. Mean LAA emptying velocity was 47.5±20.2. A total of 103 (40%) patients had recurrence after CA. In the multivariable model, after adjusting for potential confounders, LAA emptying velocity of ≥52.3 was associated with decreased AF recurrence post-ablation (OR 0.55; 95% CI: 0.31-0.97; p = 0.03*). There were 190 (73%) patients in normal sinus rhythm during TEE and CA, and sensitivity analysis of these patients showed that LAA velocity ≥52.3 remained associated with decreased AF recurrence (OR 0.35; 95% CI 0.15-0.82; p = 0.01*).

CONCLUSION

LAA emptying velocity measured during pre-procedural TEE can serve as a predictor of AF recurrence in patients undergoing CA. This article is protected by copyright. All rights reserved.

Possible mechanisms responsible for acute coronary events in COVID-19

The novel coronavirus (SARS-CoV-2) is primarily a respiratory pathogen and its clinical manifestations are dominated by respiratory symptoms, the most severe of which is acute respiratory distress syndrome (ARDS). However, COVID-19 is increasingly recognized to cause an overwhelming inflammatory response and cytokine storm leading to end organ damage. End organ damage to heart is one of the most severe complications of COVID-19 that increases the risk of death. We proposed a two-fold mechanism responsible for causing acute coronary events in patients with COVID-19 infection: Cytokine storm leading to rapid onset formation of new coronary plaques along with destabilization of pre-existing plaques and direct myocardial injury secondary to acute systemic viral infection. A well-coordinated immune response is the first line innate immunity against a viral infection. However, an uncoordinated response and hypersecretion of cytokines and chemokines lead to immune related damage to the human body. Human Coronavirus (HCoV) infection causes infiltration of inflammatory cells that cause excessive production of cytokines, proteases, coagulation factors, oxygen radicals and vasoactive molecules causing endothelial damage, disruption of fibrous cap and initiation of formation of thrombus. Systemic viral infections also cause vasoconstriction leading to narrowing of vascular lumen and stimulation of platelet activation via shear stress. The resultant cytokine storm causes secretion of hypercoagulable tissue factor without consequential increase in counter-regulatory pathways such as AT-III, activated protein C and plasminogen activator type 1. Lastly, influx of CD4+ T-cells in cardiac vasculature results in an increased production of cytokines that stimulate smooth muscle cells to migrate into the intima and generate collagen and other fibrous products leading to advancement of fatty streaks to advanced atherosclerotic lesions. Direct myocardial damage and cytokine storm leading to destabilization of pre-existing plaques and accelerated formation of new plaques are the two instigating mechanisms for acute coronary syndromes in COVID-19.

Traumatic Intracranial Aerocele With Progressive Blindness - A case report

BACKGROUND

Traumatic intracranial aerocele, also known as pneumocephalus, is an uncommon condition that may be asymptomatic or may present with progressive neurological deficits and life threatening conditions that demand urgent decompressive craniotomy to reduce the acute rise in intracranial pressure and the sequelae.

AIMS & OBJECTIVES

A high degree of suspicion and continuous neurological monitoring are essential for the early detection and the prompt neurosurgical intervention demanded for the achievement of a good outcome in patients following traumatic acute severe head injury with life threatening neurological complications.

METHOD

Presentation of a young motorcyclist who was not wearing a crash helmet and was involved in a road traffic accident in which he sustained a compound cranio-facial injury with loss of consciousness and symptomatic intracranial aerocele.

RESULTS

The case of a 28-year old motorcyclist without a helmet, following a road traffic accident, sustained compound skull fracture with CSF rhinorrhea, ventricular aerocele and progressive blindness who recovered his vision fully following bitemporal decompressive craniotomy.

CONCLUSION

A high index of suspicion enabled early detection and prompt decompressive craniotomy that stemmed the progressive loss of vision in this patient with an uncommon but symptomatic intracranial aerocele and cranio-facial compound head injury.

Diminished prevalence but preserved synaptic distribution of N-methyl-D-aspartate receptor subunits in the methyl CpG binding protein 2(MeCP2)-null mouse brain

In this study, we examined the prevalence and distribution of NMDA receptor subunits within crude synaptic membranes derived from the brains of mice lacking methyl CpG binding protein 2 (MeCP2). Our results show that the distribution of NMDA receptor subunits within the detergent soluble, detergent resistant, and postsynaptic density microdomains is preserved at MeCP2-null synapses. However, analysis of the NMDA receptor subunit expression revealed a decrease in the prevalence of the GluN1 and GluN2A subunits in MeCP2-null tissue. Collectively, these results indicate that synaptic membrane microdomains at synapses of the MeCP2-null brain develop normally, and that NMDA receptor subunits are properly targeted and distributed within them. The under-representation of the GluN1 and GluN2A subunits suggests that MeCP2-null synapses contain fewer mature NMDA receptor complexes, and raises the possibility that impaired NMDA receptor ontogeny could contribute to Rett syndrome pathophysiology.

Ileosigmoid knotting--a case for primary anastomosis

BACKGROUND

Resection of gangrenous/non-viable bowel followed by primary anastomoses is known to be a viable option for treatment of ileosigmoid knotting. We here report a case of ileosigmoid knot and examined the options for treatment.

METHOD

A case report of a patient with ileosigmoid knotting and discussion of relevant literature for surgical treatment.

RESULT

A 26 year old man presented to the accident and emergency unit with two weeks' history of fever and alternating diarrhea and constipation followed by features of intestinal obstruction and later, generalized peritonitis. Plain abdominal X-rays showed dilated loops of bowel and multiple air-fluid levels. The diagnosis of ileosigmoid knotting was missed preoperatively. At exploratory laparotomy, ileosigmoid knot was encountered with non-viable segments of the sigmoid colon and ileum. Resection of the non-viable bowel was carried out with primary anastomoses with good postoperative outcome.

CONCLUSION

Primary anastomoses after resection of gangrenous bowel is a safe surgical treatment option in ileosigmoid knotting.