Hibernation of the Conduction System and Atrioventricular Block Reversibility Following Revascularization in Patients without Acute Coronary Syndrome.

Although myocardial infarction (MI) is a reversible cause of atrioventricular (AV) block, the association of ischemia other than MI with AV block is unclear. The purpose of this study is to investigate this relationship. Among patients nominated for pacemaker implantation due to AV block in two centers from 2017-2020, 120 patients with significant coronary artery disease (CAD) in angiography were included in the study. Patients were divided into two equal groups based on their CAD treatment approach: drug therapy and revascularization. Coronary lesions were divided into three types based on location: left anterior descending artery (type 1), dominant coronary with AV node branch (type 2), and a combination of both (type 3). After coronary disease treatment, all patients were followed up with for 14 months, and AV block reversibility was assessed. There were 7 cases of block reversibility in the revascularization group (11.7%) and 1 case in the medical group (1.7%), which differed significantly (P = .02). A history of acute coronary syndrome, smoking, opium use, chronic kidney disease, hypertension, age, sex, and chronic obstructive pulmonary disease were not significantly associated with reversible block. Also, the type of coronary obstruction had no significant relationship with block reversibility (P = .3, .5, and .8 for type 1, type 2, and type 3, respectively). Hibernation due to ischemia can be a reversible cause of an AV blockage. Therefore, it is recommended that significant coronary artery lesions be revascularized before pacemaker implantation.

Clinical outcomes of subcutaneous implantable cardiac defibrillator implantation - Iran SICD registry.

BACKGROUND: The subcutaneous implantable-defibrillator (S-ICD) is a relatively new alternative to the transvenous ICD system to minimize intravascular lead-related complications. This paper presents outcome of SICD implantation in patients enrolled in Iran S-ICD registry. METHODS: Between October 2015 and June 2022, this prospective multicenter national registry included 223 patients with a standard indication for an ICD, who neither required bradycardia pacing nor needed cardiac resynchronization to evaluate the early post-implant complications and long-term follow-up results of the S-ICD system. RESULTS: The mean age of the patients was 45 ± 17 years. The majority (79.4%) were male. Ischemic cardiomyopathy (39.5%) was the most common underlying disorder among patients selected for S-ICD implant. Most study patients (68.6%) had ICD for primary prevention of sudden cardiac death. Seven patients (3.1%) were found to have suboptimal lead positions. Six patients (2.7%) developed a pocket hematoma; all were managed medically. During a mean follow-up of 2 years, the appropriate therapy was recorded in 13% of the patients and inappropriate ICD intervention mainly due to supraventricular tachycardia in 8.9%. Pocket infection was observed in four patients (1.8%) and five patients (2.2%) died mainly due to heart failure. CONCLUSION: S-ICDs were effective at detecting and treating both induced and spontaneous ventricular arrhythmias. Major clinical complications were rare.

Posteroseptal accessory pathway in association with coronary sinus diverticulum: electrocardiographic description and result of catheter ablation.

AIMS: A precise knowledge of the coronary sinus (CS) anatomy and its potential anomalies seems essential to increase the rate of success in patients with a prior history of multiple ablation failures of the posteroseptal accessory pathway or in whom this procedure cannot be performed easily. We aimed to describe the anatomic and electrocardiographic characteristics of the CS diverticulum in association with the posteroseptal accessory pathway and subsequent catheter ablation results. METHODS: We retrospectively recruited 12 patients with posteroseptal accessory pathways associated with CS diverticula from patients referred to Tehran Heart Center for electrophysiological study and ablation between January 2004 and December 2011. RESULTS: The study population consisted of eight males and four females at a mean age of 48.2 ± 17.5 years with posteroseptal accessory pathways. The most frequent initial presentation was orthodromic atrioventricular re-entrant tachycardia and atrial fibrillation. The rate of acute success for radiofrequency ablation and the recurrence rate were 75 and 16.6 %, respectively. Larger diverticula tended to have more failure and recurrence rate, albeit not significant. None of the patient's characteristics could significantly predict the success of the ablation. CONCLUSION: Our total initial failure rate and subsequent recurrence was around 41 %. Better results might have been achieved had we applied irrigated tip catheters or NavX(TM)-guided cryoablation or subxiphoid epicardial mapping and ablation.

Regarding case report "povidone iodine irrigation - a possible alternative to lead extraction".

We read the case report of Dr. Puri and colleagues for treating an infected permanent pacemaker conservatively in an elderly patient. Due to its similarity of this work with ours, we wish to highlight some points regarding conservative treatment of pacemaker infection.

Unusual treatment of pacemaker pocket infection: a case report.

Pocket infection of a cardiac device is usually treated by removing the device and re-implanting it in a new site after complete treatment of the infection. This report illustrates a complicated case of pocket infection in the wake of the implantation of a permanent pacemaker (cardiac resynchronization therapy). The patient was treated conservatively through daily irrigation and dressing, broad-spectrum antibiotics, and debridement without the device being removed; the generator was kept out of the pocket for 5 weeks and then re-implanted in the same location successfully.The method of treatment presented herein can be of value, not least in the elderly population who might experience life-threatening events following the replacement of their cardiac devices.

Anomalous right-sided pulmonary venous connection to the superior vena cava.

Over the years, different techniques have been introduced for the repair of sinus venosus atrial septal defect (ASD) with anomalous right-sided pulmonary venous connection to the superior vena cava. We report the case of a 9-year-old girl, who presented with dyspnea and peripheral cyanosis. Preoperative echocardiography and angiography findings suggested a partial anomalous pulmonary venous connection. On cardiopulmonary bypass, the ASD was dilated, and the anomalous pulmonary vein was anastomosed to the right atrium and redirected to the left atrium using an intraatrial baffle and a tube graft. The intraoperative and postoperative periods were uneventful, and the patient is currently in good health at 4.5 years' follow-up.