Pitfalls in electrogram interpretation: Subcutaneous cardioverter defibrillator malfunction in Brugada syndrome.

A patient with Brugada syndrome implanted with subcutaneous implantable cardioverter defibrillator (S-ICD) had oversensing episodes treated with S-ICD shocks. Comparable artifacts were not evocable with S-ICD pocket manipulation. The fluoroscopy excluded S-ICD macroscopic damage. The device extraction revealed undamaged pulse generator and connector, but the lead was inappropriately tunneled under the sixth rib. Then the S-ICD malfunction was due to lead microscopic damage caused by the lead rubbing the rib surface.

Early atrial fibrillation detection is associated with higher arrhythmic burden in patients with loop recorder after an embolic stroke of undetermined source.

Background: After an embolic stroke of undetermined source (ESUS), long-term monitoring is recommended to start an anticoagulation therapy in patients with documented atrial fibrillation (AF). Literature is sparse about the AF burden following an ESUS, although this might have significant implications in terms of clinical management and therapeutic strategy. Our primary aim was to evaluate a possible association between early detection of AF (within 90 days from the ILR implantation) and higher AF burden. Methods: This is a retrospective single-center study of 129 consecutive patients who received implantable loop recorders (ILRs) after an ESUS for detection of subclinical AF and their AF burden. Results: Mean age was 70.3 ± 10.4 years old (males: 51.9%). Atrial fibrillation was found in 40.3% of patients. Patients with AF were older, presented a higher CHAD2S2-Vasc Score and greater left atrial volume compared with patients without AF. The median AF burden was 1.2%; 59% of patients had the first AF episode within 90 days from the ILR implant while 41% experienced the first episode later than 90 days. The AF burden was significantly higher in the former group. Of note, the univariate analysis showed that only early AF detection was significantly associated with AF burden >1% (OR 20.0; 95% CI 1.68-238.6, p = 0.01). Conclusions: The early AF detection was found to be significantly associated with a higher burden of AF.

In-hospital follow-up of implantable cardioverter defibrillator and pacemaker carriers: patients' inconvenience and points of view. A four-hospital Italian survey.

AIMS: The increasing volume of pacemaker (PM) and implantable cardioverter defibrillator (ICD) implants and problems related to their functioning have highlighted the issue of device follow-ups. Patients' convenience regarding device visits has been little investigated. This work aims at surveying patients' efforts in attending the in-office PM/ICD follow-ups and at evaluating their expectations. METHODS AND RESULTS: In four Italian referral centres, over a 3-month period, a 20-point questionnaire was completed by all consecutive patients at in-hospital PM/ICD visits. In total, 1109 questionnaire/patients were evaluated. Pacemakers were 68%, ICDs 16%, and cardiac resynchronizations (CRTs) (PM + ICD) 16%; 38% were females; mean age was 75 ± 11 years. Almost all were scheduled visits. There was frequent reprogramming and clinical examination, even after 6 months from implant. Perceived inconvenience for the in-office follow-up was relevant in 35% of cases; attitudes towards remote monitoring were positive in 88% of cases. Inter-group analysis showed some significant difference: PM patients were older and more frequently female; ICD carriers were younger, had the highest rate of clinical evaluation, a longer journey time, and the most positive opinion about remote follow-up. Cardiac resynchronization patients had a longer waiting time and the lowest inconvenience. Overall inconvenience was independently predicted by increasing age, lengthy travelling times, and being accompanied; favourable opinions about remote monitoring were predicted by overall inconvenience, and, in ICD carriers only, by lack of clinical examination. CONCLUSIONS: Patients' perceptions of in-hospital PM/ICD visits were affected by age and by journey modalities. Individual factors seem to affect both opinions about in-office visits and expectations towards a possible remote follow-up.

Cardiac resynchronization therapy or sequential pacing in failing Mustard?

The atrial switch (Mustard, Senning procedures) was one of the treatments of choice for repair of transposition of the great arteries from the early 1960s to the mid-1980s. A significant proportion of patients with atrial switch develops systemic (right) ventricular failure. A series of surgical therapeutic options exists to manage cardiac failure in this setting, and, more recently proposed, cardiac resynchronization therapy. We describe case report of a 30-year-old woman with congenital heart disease (CHD) and previous Mustard procedure who underwent upgrading from single chamber to dual-chamber pacemaker. The narrower native QRS did not correlate with a better synchrony status nor with a better cardiac output. Functional evaluation confirmed a better performance in DDD mode with short atrioventricular delay and broad QRS. Some echocardiographic and electrocardiographic parameters, such as ejection fraction and QRS duration, well established in adults' heart for selection of candidates to cardiac resynchronization therapy, are much less studied in CHD. Postoperative CHD may provide unique patterns of asynchrony with poorly predictable hemodynamic outcome.

Implantable cardioverter-defibrillators in patients with arrhythmogenic right ventricular cardiomyopathy: the course of electronic parameters, clinical features, and complications during long-term follow-up.

PURPOSE: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a progressive cardiomyopathy characterized by myocardial atrophy and fibro-fatty replacement of the right ventricle (RV) and ventricular tachyarrhythmias in young patients. Our aim was to evaluate clinical course and electronic parameters in patients with implantable cardioverter-defibrillator (ICD) and ARVC, during long-term follow-up. METHODS AND RESULTS: We report on 12 patients with ARVC (mean age 40 ± 13 years) who were treated with ICD implantation in our center. Although several RV sites were tested for proper lead positions, the amplitude of R-wave at implantation was quite low (7.4 ± 3.0 mV). After a mean follow-up of 91 ± 28 months, R-wave amplitude significantly decreased to a mean value of 5.4 ± 2.5 mV (p=0.03). We also found a noticeable, nearly significant increase in pacing threshold (p=0.052) and a moderate increase in defibrillation impedance (p=0.07). Six patients (46 %) experienced at least one appropriate ICD therapy; three patients (23 %) experienced inappropriate ICD shocks secondary to the supraventricular tachycardia, T-wave oversensing, and electromagnetic interference. CONCLUSIONS: ICD in patients with ARVC has been demonstrated to be feasible and safe. In our case series, we found low R-wave amplitudes at implantation and a significant R-wave decrease during follow-up; a considerable and nearly significant increase in pacing threshold was also observed. These findings may be related to the progressive fibro-fatty replacement of RV myocardium. Multiple sites should be tested in the right ventricle if sensing or pacing values are not optimal, and all the electronic parameters should be carefully monitored throughout the entire follow-up.

The beneficial effect of biventricular pacing on ventricular tachycardia in a patient with non-ischemic cardiomyopathy.

The effect of cardiac resynchronisation therapy on ventricular tachycardias (VT) has not been well established. This case-report demonstrates the favourable impact of biventricular pacing on ventricular arrhythmias. In 2004, a patient with dilated cardiomyopathy and ICD since 1999 was admitted to our Division for multiple VT. While left ventricular function was markedly reduced and mitral regurgitation was severe, he was asymptomatic for heart failure. Amiodarone was not administered on account of a documented proarrhythmic effect. The patient's ICD was upgraded to an ICD-biventricular system. After upgrading, a significant reduction in the number of VT was noted.

Antihypertensive effects of lacidipine during effort in mild to moderate hypertension.

The aim of this study was to evaluate the effects of chronic treatment with lacidipine on blood pressure, heart rate and double product during and immediately after physical effort in mild to moderate hypertensive patients. This was a single-center, randomized, double-blind, crossover, placebo-controlled clinical trial. Eighteen hypertensive patients (56% males, median age 53 years) were randomized to lacidipine 4 mg o.i.d. followed by placebo or to placebo followed by lacidipine 4 mg o.i.d. Lacidipine compared with placebo exerted a significant antihypertensive effect, lowering SBP and DBP both at baseline and either during or after exercise test. The average incremental changes of SBP and DBP between pre-exercise stage and maximal effort did not show any significant differences between treatments. HR during treatment with lacidipine was higher than during treatment with placebo both at rest and after exercise, but at maximal effort, HR was not different from placebo. The average values of DP at maximal effort, and during recovery, did not show any significant differences. Lacidipine 4 mg was effective in lowering blood pressure and in maintaining its antihypertensive effect throughout and after physical exercise, without enhancing double product value, which is an indirect index of myocardial oxygen consumption.