Swallowing-induced Paroxysmal Atrial Tachycardia Causes Weight Loss and Fainting during Mealtime: A Case Report and Literature Review

Swallow or deglutition syncope is an unusual disorder. We herein report an 80-year-old man with paroxysmal atrial tachycardia induced by swallowing, causing syncope. Initially, we suspected a digestive disorder and found no significant findings. Finally, a swallowing test with monitoring of the heart rate and blood pressure helped in the diagnosis. The patient was treated with antiarrhythmic drugs and catheter ablation. The mechanism underlying swallowing-induced tachycardia presumably involves mechanical stimulation of the esophagus and autonomic nervous system effects. However, few cases have been reported, and the exact mechanism remains unclear.

One-year clinical outcomes of anticoagulation therapy among Japanese patients with atrial fibrillation: The Hyogo AF Network (HAF-NET) Registry

BACKGROUND

Although anticoagulation therapy could reduce the risk of strokes in patients with atrial fibrillation (AF), large-scale investigations in the direct oral anticoagulant (DOAC) and AF catheter ablation (CA) era are lacking.

METHODS

This study was designed as a prospective, multicenter, observational study and a total of 2113 patients from 22 institutions were enrolled in the Hyogo area.

RESULTS

The mean age and CHADS2 score were 70.1 ± 10.8 years old and 1.5 ± 1.1, respectively. The follow-up period was 355 ± 43 days. CA was performed in 614 (29%) and DOACs were prescribed in 1118 (53%) patients. Ischemic strokes/systemic embolisms (SEs) and major bleeding occurred in 13 (0.6%) and 17 (0.8%) patients, respectively. New onset dementia, hospitalizations for cardiac events, and all-cause death occurred in eight (0.4%), 60 (2.8%), and 29 (1.4%) patients, respectively. A multivariate analysis demonstrated that persistent AF and the body weight (BW) were associated with ischemic strokes/SEs and major bleeding, respectively (persistent AF: hazard ratio, 9.57; 95%CI, 1.2-74.0; P = .03; BW: hazard ratio, 0.94; 95%CI, 0.90-0.99; P = .02). AFCA history was associated with the cardiac events (hazard ratio, 0.44; 95%CI, 0.20-0.99; P = .04). Age was associated with new onset dementia (hazard ratio, 1.1; 95%CI, 1.0-1.2; P = .03).

CONCLUSIONS

In the DOAC and CA era, the incidence of ischemic strokes/SEs, major bleeding and cardiac events could be dramatically reduced in patients with AF. However, some unsolved issues of AF management still remain especially in elderly patients with persistent AF and a low BW.

Percutaneous Pericardiocentesis With the Anterior Approach: Demonstration of the Precise Course With Computed Tomography

OBJECTIVES

This study aimed to confirm the precise course of a pericardiocentesis with the anterior approach using post-procedural computed tomography (CT).

BACKGROUND

Percutaneous epicardial ventricular tachycardia (VT) ablation has been increasingly performed. Although the inferior approach has been the common method, the feasibility of the anterior approach has subsequently been reported. However, the precise course of the anterior approach has not been presented.

METHODS

An epicardial ablation with the anterior approach was performed in 15 patients. At the end of the procedure, the epicardial sheath was exchanged for a drainage tube to monitor bleeding. Of those patients, in 9 procedures in 8 patients a CT scan was performed just after the procedure to confirm the course of the drainage tube and to rule out any complications. Epicardial ablation was indicated for a failed endocardial VT ablation in 7 patients and epicardial substrate modification in 1 patient with Brugada syndrome.

RESULTS

Volume-rendered images reconstructed from CT demonstrated each course of the drainage tubes and their relation to the surrounding organs. These images revealed that the tube had a curved trace, and did not penetrate the diaphragm or pass through the abdominal cavity. No injury to the surrounding organs was detected in any of the cases.

CONCLUSIONS

The precise course of the drainage tube placed along the trajectory of the anterior approach was able to be confirmed using post-procedural CT images. These images support the safety and feasibility of the anterior approach from the anatomic standpoint with a low incidence of abdominal viscera injury.

The lesion characteristics assessed by LGE-MRI after the cryoballoon ablation and conventional radiofrequency ablation

Background

Rhythm outcomes after the pulmonary vein isolation (PVI) using the cryoballoon (CB) are reported to be excellent. However, the lesions after CB ablation have not been well discussed. We sought to characterize and compare the lesion formation after CB ablation with that after radiofrequency (RF) ablation.

Methods

A total of 42 consecutive patients who underwent PVI were enrolled (29 in the CB group and 13 in the RF group). The PVI lesions were assessed by late gadolinium enhancement magnetic resonance imaging 1–3 months after the PVI. The region around the PVs was divided into eight segments: roof, anterior‐superior, anterior‐carina, anterior‐inferior, bottom, posterior‐inferior, posterior‐carina, and posterior‐superior segment. The lesion width and lesion gap in each segment were compared between the two groups. Lesion gaps were defined as no‐enhancement sites of >4 mm.

Results

As compared to the RF group, the overall lesion width was significantly wider and lesion gaps significantly fewer at the anterior‐superior segment of the left PV (LAS) and anterior‐inferior segment of the right PV (RAI) in the CB group (lesion width: 8.2 ± 2.2 mm vs 5.6 ± 2.0 mm, P = .001; lesion gap at LAS: 7% vs 38%, P = .02; lesion gap at RAI: 7% vs 46%, P = .006).

Conclusions

The PVI lesions after CB ablation were characterized by extremely wider and more continuous lesions than those after RF ablation.

Predictors and Clinical Outcomes of Transient Responders to Cardiac Resynchronization Therapy

BACKGROUND

Left ventricular end-systolic volume (LVESV) changes at 6 months and clinical status are useful for assessing responses to cardiac resynchronization therapy (CRT). Regression of the LVESV following CRT has not been described beyond 6 months. This study aimed to assess the proportion, predictors, and clinical outcomes of responders whose LVESVs had regressed.

METHODS

We retrospectively analyzed 104 consecutive CRT patients. A responder was defined as a patient with a relative reduction in the LVESV ≥15% at 6 months after CRT. Fifty-six responders participated in this study. A transient responder was defined as a responder without a relative reduction in the LVESV ≥15% at 2 years after CRT or who died of cardiac events during the 24-month follow-up period.

RESULTS

Of the 56 responders, 16 (29%) were transient responders. Multivariable logistic regression analysis showed that chronic atrial fibrillation (odds ratio [OR] = 19.2, 95% confidence interval [CI] [1.93, 190], P = 0.012) and amiodarone usage (OR = 60.9, 95% CI [4.18, 886], P = 0.003) were independent predictors of transient responses. Hospitalizations for heart failure were significantly higher among the transient responders than among the lasting responders during a mean follow-up period of 7.6 years (log-rank P < 0.001), and all-cause mortality tended to be higher among the transient responders (log-rank P = 0.093).

CONCLUSIONS

One-third of the responders were transient responders at 2 years after CRT, and their long-term prognoses were poor. Careful attention should be paid to maintain the reduction in LVESV especially in patients with chronic AF.

Characteristics of Residual Atrial Posterior Wall and Roof-Dependent Atrial Tachycardias after Pulmonary Vein Isolation

BACKGROUND

Roof-dependent atrial tachycardia (roof AT) sometimes occurs after pulmonary vein isolation (PVI) of atrial fibrillation (AF). This study aimed to investigate the relationship between the anatomy of the residual left atrial posterior wall and occurrence of roof AT.

METHODS

A total of 265 patients with AF who underwent PVI were enrolled. After the PVI, induced or recurrent roof AT was confirmed by an entrainment maneuver or activation mapping using a three-dimensional (3D) mapping system. To identify the predictors of roof AT, the minimum distance between both PVI lines (d-PVI) was measured by a 3D mapping system and the anatomical parameters, including the left atrial (LA) diameter, left atrial volume index (LAVi), and shape of the left atrial roof, were analyzed by 3D computed tomography.

RESULTS

Roof AT was documented in 11 (4.2%) of 265 patients. A multivariable analysis demonstrated that the d-PVI, Deep V shape of the LA roof, and LAVi were associated with roof AT occurrences (d-PVI: odds ratio: 0.72, confidence interval [CI]: 0.61-0.86, P < 0.001; Deep V shape: odds ratio: 0.19, CI: 0.04-0.82, P = 0.03; LAVi: odds ratio: 1.05, CI: 1.02-1.07, P = 0.001). A receiver-operating characteristic curve analysis yielded an optimal cut-off value of 15.5 mm and 55.7 mL/m² for the d-PVI and LAVi, respectively.

CONCLUSION

The shorter d-PVI at the LA roof, greater LAVi, and Deep V shape were associated with the occurrence of a roof AT.

The Relationship Between Cardiac Vulnerability and Restitution Properties of the Ventricular Activation Recovery Interval

INTRODUCTION

The restitution of the action potential duration (APD) is an important contributor to ventricular fibrillation (VF) initiation by a single critically timed ectopic beat. We hypothesized that a steep slope of the activation recovery interval restitution curve was related to the upper limit of vulnerability (ULV).

METHODS AND RESULTS

Fifty-four consecutive patients with implantable cardioverter defibrillators (ICDs) implanted between April 2012 and July 2013 were included. At the implantation, pacing from the right ventricular (RV) coil to an indifferent electrode inserted in the ICD pocket was performed, and the unipolar electrograms from the RV coil were simultaneously recorded. We assessed the standard restitution by introducing extra-stimuli, while measuring the activation recovery interval (ARI). Our protocol for the vulnerability test consisted of delivering three 15 J shocks on the T-peak and within ±20 milliseconds of it. If VF was not induced by that procedure, a ULV of ≤15 J was defined. The relationship between the ULV and maximum slope of the restitution curve was analyzed. A restitution curve could finally be obtained in a total of 40 patients. The background characteristics were similar between the two groups. The maximum slope of the restitution curve was steeper in the ULV > 15 J group than ULV ≤ 15 J group (1.55 ± 0.45 vs. 0.91 ± 0.64, P < 0.05). A maximum slope exceeding 1.0 was the optimal point for discriminating patients with a ULV > 15 J from a ULV ≤ 15 J (sensitivity 61.5% and specificity 96.3%).

CONCLUSION

The maximum slope of the restitution curve was significantly related to the ULV. High defibrillation threshold patients could be detected by the ARI dynamics.