UNASSIGNED: Abnormal substrate on invasive electroanatomic mapping (EAM) correlates with areas of myocardial thinning and fibrofatty replacement in Arrhythmogenic Cardiomyopathy (ACM). However, EAM parameters are absent from all sets of diagnostic criteria for ACM.
UNASSIGNED: A 41-year-old female with no significant family history was referred for evaluation of frequent premature ventricular complexes (PVCs). Twelve-lead ECG showed diffuse low-voltage QRS complexes. Holter monitor showed 28% burden of PVCs with various morphologies consistent with right ventricular (RV) inflow and outflow tract exits. Transthoracic echocardiogram revealed normal biventricular function and dimension. Cardiac magnetic resonance revealed a mildly increased indexed RV end-diastolic volume with normal RV systolic function and no dyssynchrony, akinesia, dyskinesia, or late gadolinium enhancement. Electrophysiologic study demonstrated 2 predominant PVC morphologies that were targeted with ablation, in addition to extensive abnormality with low-voltage and fractionated electrograms in the peri-tricuspid and right ventricular outflow tract free wall regions with septal sparing, suggestive of RV cardiomyopathy. Subsequent genetic testing revealed two pathogenic variants in the desmoplakin and plakophilin-2 genes, confirming the diagnosis of ACM.
UNASSIGNED: Advanced RV electropathy can precede RV structural changes in ACM. Invasive evaluation of the electroanatomic substrate should be considered in select cases even when imaging findings are not diagnostic. Future iterations of ACM guidelines may need to consider EAM substrate as one of the diagnostic criteria. A high index of diagnostic suspicion for ACM should be maintained in patients with multifocal RV ectopy.

The epicardial outflow tract can be a site of origin of idiopathic ventricular arrhythmias. These arrhythmias are most commonly perivalvular and can be targeted from within the coronary venous system or from other adjacent structures, such as the right ventricular and left ventricular outflow tracts or the coronary cusp region. The authors report a case of an epicardial idiopathic outflow tract premature ventricular contraction originating from the midseptal epicardial left ventricle. In this case, direct epicardial access was crucial to identify early local activation and achieve successful catheter ablation.

Premature ventricular contraction (PVC) is usually eliminated in the earliest activation site based on the conventional electrode of ablation catheter. However, the large size electrode may contain far-field potential. The QDOT MICRO ablation catheter has three micro electrodes with 0.33 mm electrode length, in addition to the conventional electrode with 3.5 mm electrode length. The micro electrodes can reflect only near-field potential. A 78-year-old with symptomatic frequent PVCs underwent catheter ablation. PVC-1 showed good pace-mapping in distal great cardiac vein (GCV). The local bipolar electrograms in the conventional electrode of ablation catheter preceded the PVC-QRS onset by 32 ms in distal GCV and 13 ms in left coronary cusp (LCC), but those in the micro electrodes preceded only by 13 ms both in distal GCV and LCC. PVC-1 was eliminated by radiofrequency (RF) application, not in distal GCV, but in LCC. PVC-2 showed good pace-mapping in LCC. The local bipolar electrograms in both the conventional electrode and the micro electrodes of ablation catheter preceded the PVC-QRS onset by 32 ms in LCC. PVC-2 was eliminated by RF application in LCC. Comparing the local electrograms of micro electrodes and the conventional electrodes may be important for identifying depth of the origin of PVCs.

UNASSIGNED: Ryanodine receptor 1 (RYR1)-related myopathies are a group of congenital muscle diseases caused by RYR1 mutations. These mutations may cause centronuclear myopathy, a congenital neuromuscular disorder characterized by clinical muscle weakness and pathological presence of centrally placed nuclei on muscle biopsy. Mutations in RYR2 cause ventricular arrhythmias that can be treated with flecainide; however, reports of ventricular arrhythmias in RYR1-related myopathies are rare. Herein we report a case of centronuclear myopathy with RYR1 mutations who exhibited frequent premature ventricular contractions (PVCs) and non-sustained ventricular tachycardia (NSVT), which was successfully treated with verapamil and flecainide.
UNASSIGNED: At 7 months, the patient presented neurological manifestations of hypotonia and delayed motor development. A skeletal muscle biopsy performed at age 4 years led to the diagnosis of centronuclear myopathy. At age 15 years, frequent PVCs and NSVT were identified on the electrocardiogram and 24 h Holter monitoring. Treatment with verapamil was initiated; however, it was not beneficial. Therefore, flecainide was added to the treatment, decreasing the frequency of PVCs and NSVT. Non-sustained ventricular tachycardia disappeared at the age of 21, and PVCs almost disappeared at the age of 22. Genetic testing revealed c.13216delG (p.E4406Rfs*35), c.14874G>C (p.K4958N), and c.9892G>A (p.A3298T) in RYR1, and the compound heterozygosity of variants was confirmed by analysis of the parents.
UNASSIGNED: This is the first report of ventricular arrhythmia associated with RYR1-related myopathy that was successfully treated with verapamil and flecainide. The combination of verapamil and flecainide may be a useful treatment option for ventricular arrhythmias in patients with RYR1-related myopathies.

BACKGROUND: The R-on-T phenomenon is a malignant arrhythmia associated with potentially catastrophic consequences. It may initiate ventricular tachycardia or ventricular fibrillation, which can result in syncope or sudden cardiac death. This manifestation poses a great challenge for anesthesiologists. However, it is rarely encountered in the perioperative setting.
METHODS: We herein present a case in which the R-on-T phenomenon was incidentally revealed by 24-h Holter monitoring in a patient diagnosed with sigmoid colon cancer. Careful evaluation and treatment with mexiletine were carried out preoperatively under consultation with a cardiovascular specialist, and surgery was uneventfully performed under general anesthesia after thorough preparation.
CONCLUSIONS: Physicians should be vigilant about this infrequent but potentially fatal arrhythmia. Our experience suggests that the anesthetic process can be greatly optimized with careful preparation.

暂无摘要。

BACKGROUND: Coronary calcium poses a challenge for the interventional cardiologist often leading to stent under-expansion and subsequent ischemic events. Aggressive balloon post-dilatation though helpful is usually inadequate. Multiple plaque ablation techniques are in vogue, but they are technically demanding and are not without complications. Shockwave intravascular lithotripsy (S-IVL) has emerged as a user-friendly and effective mechanism for calcium management with a high safety margin. A series of trials (DISRUPT CAD I-IV) have demonstrated both short-term and long-term safety and efficacy of the technique. As experience with the technique grows more and more, therapy areas like stent restenosis are being covered by the S-IVL.
METHODS: We report a series of 2 cases successfully managed with S-IVL therapy at our center. The first case is of a 57-year-old smoker who presented with acute coronary syndrome. His left anterior descending coronary artery revealed calcified 90% stenosis on angiogram and a combination of superficial-deep calcium on intracoronary imaging. The calcium was treated with 20 pulses of S-IVL to create discontinuity and a sirolimus eluting drug-eluting stent was successfully implanted. The second case is that of an elderly lady who presented with stable angina and demonstrated diffuse calcified lesions in the left anterior descending artery on angiogram. She also demonstrated a mixture of superficial and deep seated calcium zones on imaging. S-IVL therapy was applied to generate fractures in calcium, and two overlapping drug-eluting stents were implanted successfully without any complications.
CONCLUSIONS: S-IVL is an emerging, efficient, user-friendly and safe therapy for managing intracoronary calcium in routine interventional practice.

His and proximal left bundle (LB) electrogram recordings revealed that His or LB potential always preceded multiple premature ventricular contractions (PVCs). Some ectopic LB discharges showed exit block inside the proximal LB. This appears to implicate pathological His-Purkinje tissue with longitudinal dissociation. Co-treatment with verapamil 240 mg/day and quinidine 300 mg/day could suppress PVCs and eliminate symptoms. Genetic analysis revealed a rare variant in LMNA in this patient.

Coronary venous spasm has never been reported during premature ventricular extrasystole ablation. We report a 20-year-old female patient who experienced a severe spasm of the great cardiac vein during radiofrequency ablation for premature ventricular contractions, which were relieved eventually by the administration of intracoronary nitroglycerine. The operation was successfully completed, leading to a long-term resolution of her palpitation symptoms.

Adaptive support ventilation (ASV) is a proposed treatment option for central sleep apnea (CSA). Although the effectiveness of ASV remains unclear, some studies have reported promising results regarding the use of ASV in patients with heart failure with preserved ejection fraction (HfpEF). To illustrate the importance of suspecting and diagnosing sleep-disordered breathing (SDB) in older adults unable to recognize symptoms, we discuss a case in which ASV was effective in a patient with CSA and HfpEF, based on changes in the Holter electrocardiogram (ECG).
An 82-year-old man presented to our hospital with vomiting on April 19, 2021. Approximately 10 years before admission, he was diagnosed with type 1 diabetes mellitus and recently required full support from his wife for daily activities due to cognitive dysfunction. Two days before admission, his wife was unable to administer insulin due to excessively high glucose levels, which were displayed as \"high\" on the patient\'s glucose meter; therefore, we diagnosed the patient with diabetic ketoacidosis. After recovery, we initiated intensive insulin therapy for glycemic control. However, the patient exhibited excessive daytime sleepiness, and numerous premature ventricular contractions were observed on his ECG monitor despite the absence of hypoglycemia. As we suspected sleep-disordered breathing (SDB), we performed portable polysomnography (PSG), which revealed CSA. PSG revealed a central type of apnea and hypopnea due to an apnea-hypopnea index of 37.6, which was > 5. Moreover, the patient had daytime sleepiness; thus, we diagnosed him with CSA. We performed ASV and observed its effect using portable PSG and Holter ECG. His episodes of apnea and hypopnea were resolved, and an apparent improvement was confirmed through Holter ECG.
Medical staff should carefully monitor adult adults for signs of or risk factors for SDB to prevent serious complications. Future studies on ASV should focus on older patients with arrhythmia, as the prevalence of CSA may be underreported in this population and determine the effectiveness of ASV in patients with HfpEF, especially in older adults.