Late presentation of arrhythmogenic right ventricular cardiomyopathy in an octogenarian associated with a pathogenic variant in the plakophilin 2 gene: a case report.

BACKGROUND: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited myocardial disease characterized by fibrofatty replacement and ventricular arrhythmias. ARVC is believed to be a disease of the young, with most cases being diagnosed before the age of 40 years. We report here a case of newly diagnosed ARVC in an octogenarian associated with a pathogenic variant in the plakophilin 2 gene (PKP2). CASE PRESENTATION: An 80-year-old Japanese man was referred for sustained ventricular tachycardia. His baseline electrocardiogram showed negative T waves in V1-V4. Right ventriculography showed right ventricular aneurysm. Because this case met three major criteria, ARVC was diagnosed. He was successfully treated with radiofrequency ablation and oral amiodarone. Genetic analysis identified an insertion mutation in exon 8 of PKP2 (1725_1728dupGATG), which caused a frameshift and premature termination of translation (R577DfsX5). CONCLUSIONS: To the best of our knowledge, this is the first report of newly diagnosed ARVC in an octogenarian associated with a loss-of-function PKP2 pathogenic variant. Although the late clinical presentation of ARVC is rare, it should be included in the differential diagnosis when treating older patients with ventricular tachyarrhythmias.

Clinical characteristics associated with pacing-induced cardiac dysfunction: a high incidence of undiagnosed cardiac sarcoidosis before permanent pacemaker implantation.

Previous studies suggested that right ventricular pacing was associated with pacing-induced cardiac dysfunction (PICD). The purpose of this study was to investigate the clinical characteristics including the incidence of undiagnosed cardiac sarcoidosis (CS) in patients with atrioventricular block (AVB) who manifest PICD. We retrospectively investigated consecutive patients with permanent pacemaker (PPM) undergoing a first-generator replacement surgery with a new PPM or an upgrade procedure to a cardiac resynchronization therapy (CRT) device between December 1, 2011 and June 30, 2017. Patients with AVB showing normal echocardiographic findings before PPM implantation were included and divided into 2 groups: patients with post-PPM left ventricular ejection fraction (LVEF) < 40% and/or undergoing an upgrade procedure to CRT (PICD group) and patients with post-PPM LVEF ≥ 40% who underwent replacement surgery with a new PPM (no-PICD group). There were 15 and 41 patients in the PICD and no-PICD groups, respectively. A wider-paced QRS duration just after the PPM implantation and/or lower pre-PPM LVEF was observed in the PICD group. Furthermore, 46.7% of the PICD patients (7/15) satisfied the diagnostic criteria for CS according to the guideline of the Japanese Circulation Society, although no patients fulfilled these criteria before PPM implantation. In conclusion, a high incidence of CS was observed in patients with AVB who had PICD. However, none of these patients was diagnosed with CS before PPM implantation.

Clinical background including anticoagulant therapy in patients with atrial fibrillation in a community-based survey: the Saitama AF Registry.

Atrial fibrillation (AF) is one of the most common cardiac arrhythmias, and carries an increased risk of cardiogenic embolism. Oral anticoagulants (OACs) including warfarin and/or non-vitamin K antagonists can prevent the majority of these events. The Saitama AF Registry was a community-based survey of patients with AF in Saitama City, which represents an urban community in Japan. A total of 75 institutions participated in the registry and attempted to enroll consecutive patients with AF from September 2014 to August 2015. The aim of the present study was to examine the clinical characteristics of patients with AF using data of the Saitama AF Registry. In addition, we investigated the difference in clinical characteristics of the patients between small-sized hospitals and large-sized hospitals. A total of 3591 patients were enrolled; 57.7% of all patients were enrolled from small-sized hospitals, whereas 42.3% were from large-sized hospitals. The patients from small-sized hospitals had higher CHADS2 score than those from large-sized hospitals. Approximately, 80% of all patients were treated with OACs, and the prescription rate was higher in patients with CHADS2 score ≥ 2 from both small-sized hospitals and large-sized hospitals. In conclusion, the present study demonstrated an appropriate use of OACs for high-risk patients with CHADS2 score ≥2 in Saitama City regardless of hospital size.

Ablation of swallowing-induced atrial tachycardia affects heart rate variability: a case report.

A 47-year-old man underwent slow pathway ablation for slow-fast atrioventricular nodal reentrant tachycardia. Following the procedure, he felt palpitations while swallowing, and swallowing-induced atrial tachycardia was diagnosed. Swallowing-induced atrial tachycardia arose from the right atrium-superior vena cava junction and was cured by catheter ablation. After the procedure, the patient's heart rate variability changed significantly, indicating suppression of parasympathetic nerve activity. In this case, swallowing-induced atrial tachycardia was related to the vagal nerve reflex. Analysis of heart rate variability may be helpful in elucidating the mechanism of swallowing-induced atrial tachycardia.

Macroreentrant atrial tachycardia in patients without previous atrial surgery or catheter ablation: clinical and electrophysiological characteristics of scar-related left atrial anterior wall reentry.

INTRODUCTION: Macroreentrant atrial tachycardia (MRAT) has been described most frequently in patients with prior cardiac surgery. Left atrial tachycardia and flutter are common in patients who undergo atrial fibrillation ablation; however, few reports describe left atrial MRAT involving the regions of spontaneous scarring. Here, we describe left atrial MRAT in patients without prior cardiac surgery or catheter ablation (CA) and discuss the clinical and electrophysiological characteristics of tachycardia and outcome of CA. METHODS AND RESULTS: An electrophysiological study and CA were performed in 6 patients (3 men; age 76 ± 6 years) with MRAT originating from the left atrial anterior wall (LAAW). No patient had a history of cardiac surgery or CA in the left atrium. Spontaneous scars (areas with bipolar voltage ≤ 0.05 mV) were observed in all patients. The activation map showed a figure-eight circuit with loops around the mitral annulus (4 counterclockwise and 2 clockwise) and a low-voltage area with LAAW scarring. The mean tachycardia cycle length was 303 ± 49 milliseconds. The conduction velocity was significantly slower in the isthmus between the scar in the LAAW and the mitral annulus than in the lateral mitral annulus (0.17 ± 0.05 m/s vs 0.94 ± 0.35 m/s; P = 0.003). Successful ablation of the isthmus caused interruption of the tachycardia and rendered it noninducible in all patients. CONCLUSION: Spontaneous LAAW scarring is an unusual cause of MRAT, showing activation patterns with a figure-eight configuration. Radiofrequency CA is a feasible and effective treatment in such cases.

Prevalence and electrophysiological characteristics of typical atrial flutter in patients with atrial fibrillation and chronic obstructive pulmonary disease.

AIMS: Chronic obstructive pulmonary disease (COPD) is one of the important underlying diseases of atrial fibrillation (AF). However, the prevalence and electrophysiological characteristics of typical atrial flutter (AFL) in patients with AF and COPD remain unknown. The purpose of the present study was to investigate those characteristics. METHODS AND RESULTS: We investigated 181 consecutive patients who underwent catheter ablation of AF. Twenty-eight patients were diagnosed with COPD according to the Global Initiatives for Chronic Obstructive Lung Disease (GOLD) criteria. Forty patients with no lung disease served as a control group. We analysed the electrophysiological characteristics in these groups. Typical AFL was more common in the COPD group (19/28, 68%) than in the non-COPD group (13/40, 33%; P = 0.006). The prevalence of AFL increased with the severity of COPD: 4 (50%) of 8 patients with GOLD1, 13 (72%) of 18 patients with GOLD2, and 2 (100%) of 2 patients with GOLD3. Atrial flutter cycle length and conduction time from the coronary sinus (CS) ostium to the low lateral right atrium (RA) during CS ostium pacing before and after the cavotricuspid isthmus ablation were significantly longer in the COPD group than in the non-COPD group (285 vs. 236, 71 vs. 53, 164 vs. 134 ms; P = 0.009, 0.03, 0.002, respectively). CONCLUSION: In COPD patients with AF, conduction time of RA was prolonged and typical AFL was commonly observed.

Prophylactic catheter ablation for induced monomorphic ventricular tachycardia in patients with implantable cardioverter defibrillators as primary prevention.

AIMS: Prophylactic catheter ablation (CA) has been established to reduce the incidence of appropriate implantable cardioverter-defibrillator (ICD) therapy (anti-tachycardia pacing or shock) in secondary prevention patients. The aim of this study was to determine whether prophylactic CA for induced ventricular tachycardia (VT) reduces the incidence of appropriate ICD therapy in primary prevention patients. METHODS AND RESULTS: We retrospectively investigated 66 consecutive patients with structural heart disease who had undergone ICD implantation as primary prevention and electrophysiological study. Patients with hypertrophic cardiomyopathy or no inducible monomorphic VT had been excluded, and the remaining 38 patients were divided into two groups; those who had undergone prophylactic CA for induced monomorphic VT (the CA group, n = 18), and those who had not undergone CA (the non-CA group, n = 20). During a mean follow-up of 50 ± 38 months, 1 patient (5%) received appropriate ICD therapy in the CA group and 13 (65%) in the non-CA group. Kaplan-Meier survival analysis revealed a significantly higher event-free survival rates for appropriate ICD therapy in the CA group compared with the non-CA group (P = 0.003). Among the patients, one patient (5%) in the CA group and nine patients (45%) in the non-CA group suffered appropriate shock (P = 0.018). CONCLUSIONS: Prophylactic CA for induced monomorphic VT reduces the incidence of appropriate ICD therapy including shock in primary prevention patients. These results indicate that prophylactic CA may be considered for structural heart disease patients who are candidates for ICD implantation as primary prevention.

Fragmented QRS predicts cardiovascular death of patients with structural heart disease and inducible ventricular tachyarrhythmia.

BACKGROUND: Fragmented QRS (fQRS) can predict cardiac events, and inducible ventricular tachycardia/fibrillation (VT/VF) is a known high-risk factor for arrhythmic death. However, whether fQRS is a predictor of cardiac events in patients with inducible VT/VF is unknown. We aimed to evaluate whether fQRS is a predictor of cardiac events in patients with structural heart disease and inducible VT/VF. METHODS AND RESULTS: We retrospectively investigated 98 patients with structural heart disease who had a defibrillator device implanted. All patients underwent electrophysiological testing prior to or after device implantation and VT/VF was induced. fQRS was present in 30 patients. Appropriate defibrillator therapies were similar between the fQRS and non-fQRS groups (47% vs. 47%). In total, 25 patients (26%) died during a mean follow-up period of 87±43 months. All-cause mortality (12 [40%] vs. 13 [19%]) and cardiovascular deaths (9 [30%] vs. 4 [6%]) were significantly higher in the fQRS group than non-fQRS group, respectively; Kaplan-Meier analysis revealed significantly lower event-free survival for all-cause mortality (P=0.012) and cardiovascular deaths (P=0.001) for fQRS patients. A multivariable Cox regression model revealed that fQRS was an independent predictor of cardiovascular death (hazard ratio, 4.58; 95% confidence interval, 1.34-15.64; P=0.015). CONCLUSIONS: fQRS is a predictor of cardiovascular death in patients with structural heart disease and inducible VT/VF.

Coronary vasospasm induced by cisplatin for seminoma.

Vascular toxicity is one of serious complications following cisplatin-based chemotherapy. This case suggests that cisplatin has a potential risk of delayed occurrence of vasospastic angina. It is important to perform careful history taking including discontinued drugs for differential diagnosis of chest pain.

Marshall bundle reentrant atrial tachycardia after the Cox-Maze IV procedure: The last barrier of the conduction pathway between the coronary sinus and left atrium.

A 74-year-old woman who developed atrial tachycardia following the Cox-Maze IV procedure underwent catheter ablation. The reentrant circuit included the coronary sinus (CS), Marshall bundle (MB), distal MB-left atrial (LA) connection, and anterolateral mitral annulus. The distal MB-LA connection was the last barrier in the conduction pathway between the CS and the left atrium.