Comparison of pharmacological treatment alone vs. treatment combined with implantable cardioverter defibrillator therapy in patients older than 75 years.

AIMS: Implantable cardioverter defibrillator (ICD) reduces mortality in selected patients. However, its role in patients older than 75 years is not well established. METHODS AND RESULTS: We performed a retrospective, non-randomized study using a historical cohort from a single centre. Between January 2008 and July 2014, we assessed patients aged ≥75 years with left ventricular ejection fraction ≤ 35%, identifying 385 patients with a Class I or IIa recommendation for ICD implantation. At the decision of the patient or attending cardiologists, 92 patients received an ICD. To avoid potential confounding factors, we used propensity-score matching. Finally, 126 patients were included (63 with ICD). The mean age was 79.1 ± 3.1 years (86.5% male). As compared with the medical therapy group, the ICD patients had a lower percentage of chronic obstructive pulmonary disease (19.0% vs. 38.1%, P < 0.05) and more frequent use of beta-blockers (BBs) (85.7 vs. 70.0%, P < 0.05). Other treatments were otherwise similar in both groups. There were no differences related to age, aetiology, or other co-morbidities. During follow-up (39.2 ± 22.4 months), total mortality was 46.0% and cardiovascular events (death or hospitalization) occurred in 66.7% of the patients. A multivariate analysis revealed that only BB therapy was shown to be an independent protective variable with respect to mortality [hazard ratio 0.4 (0.2-0.7)]. ICD therapy did not reduce overall mortality or the rate of cardiovascular events. CONCLUSIONS: According to our results, the use of ICD, as compared with medical therapy, in patients older than 75 years did not demonstrate any benefit. Well-designed randomized controlled studies in patients older than 75 years are needed to ascertain the value of ICD therapy.

Corrigendum to "Regional variations in baseline characteristics of cardiac rhythm device recipients: The PANORAMA observational cohort study" [Int. J. Cardiol. Heart Vessels (2014) 90-96].

[This corrects the article DOI: 10.1016/j.ijchv.2014.06.008.].

Association between ventricular pacing and persistent atrial fibrillation in patients indicated to elective pacemaker replacement: Results of the Prefer for Elective Replacement MVP (PreFER MVP) randomized study.

BACKGROUND: Pacing in the right ventricle can cause a variety of detrimental effects, including atrial tachyarrhythmias (atrial tachycardia [AT]/atrial fibrillation [AF]). OBJECTIVE: The purpose of this study was to evaluate the incidence and predictors of persistent AT/AF in patients with long-term exposure to ventricular pacing. METHODS: In a multicenter international trial, 605 patients (age 75 ± 11 years, 240 women) referred for replacement of an implanted pacemaker or implantable cardioverter-defibrillator (ICD), with a history of high-percentage (>40%) ventricular pacing, were randomly allocated to standard dual-chamber pacing or managed ventricular pacing (MVP), a pacing modality that minimizes ventricular pacing. The main end-point of this secondary analysis of the PreFER MVP randomized study was persistent AT/AF, defined as ≥7 consecutive days with AT/AF or AT/AF interrupted by atrial cardioversion or AT/AF present during 2 consecutive follow-up visits. RESULTS: Persistent AT/AF was observed in 71 patients (11.7%) after 2 years of follow-up. At multivariable Cox regression analysis, prior AT/AF (hazard ratio [HR] 2.85, 95% confidence interval [CI] 1.20-6.22, P = .017) and ventricular pacing percentage, estimated in the first 3 months, ≥10% (HR 3.24, 95% 95% CI 1.13-9.31, P = .029) were independent predictors for persistent AT/AF. MVP was associated with persistent AT/AF risk (HR 3.41, 95% 95% CI 1.10-10.6, P = .024) in the subgroup of patients with baseline long PR interval (PR >230 ms) but not in the whole population. CONCLUSION: In pacemaker and ICD replacement patients, a high percentage of ventricular pacing is associated with higher risk of persistent AT/AF. Use of algorithms that minimize right ventricular pacing may benefit patients with normal spontaneous AV conduction but should be evaluated with caution in patients with long PR interval.

Comparison of pharmacological treatment alone versus treatment combined with cardiac resynchronization therapy in patients over 75 years.

BACKGROUND: The role of cardiac resynchronization therapy (CRT) in patients aged ≥75 years is not well established. METHODS: We identified 607 patients aged ≥75 years with left ventricular ejection fraction (LVEF) of ≤35 %, of whom 78 met the guidelines for indication of CRT. Based on the decision of the patients or attending cardiologists, 34 patients received a CRT defibrillator (CRT-D). RESULTS: The age of patients with a CRT indication was 80 ± 4 years, and 73 % were males. As compared with patients on medical therapy, CRT-D patients were younger (79 ± 3 vs. 83 ± 4, P < 0.001), had lower LVEF (23 ± 7 vs. 27 ± 7 %, P = 0.008) and higher rate of decompensated heart failure episodes (77 vs. 55 %, P = 0.04), were more frequently New York Heart Association (NYHA) class III-IV (53 vs. 25 %, P = 0.01), and were more likely to be on beta-blockers (88 vs. 66 %, P = 0.023), anticoagulants (61 vs. 32 % P = 0.02), and anti-aldosterone drugs (82 vs. 50 %, P = 0.003). After a median follow-up of 26 months, seven patients in the CRT-D group (21 %) and 20 non-CRT patients (46 %) died (hazard ratio (HR) 0.16 [95 % confidence interval (CI) 0.06-0.46]). The end point of mortality or hospitalization was not reduced because of a similar rate of hospitalizations for heart failure of CRT-D patients. Four CRT-D patients (12 %) had received appropriate device therapy, and one had been inappropriately discharged. During follow-up, 44 % of CRT-D patients improved their LVEF by >40 %. CONCLUSION: CRT-D is potentially of benefit in terms of mortality in our population; this effect persists after correction for use of beta-blockers. In patients ≥75 years, CRT indications should be similar to those accepted for younger subjects.

Managed ventricular pacing compared with conventional dual-chamber pacing for elective replacement in chronically paced patients: results of the Prefer for Elective Replacement Managed Ventricular Pacing randomized study.

BACKGROUND: Several studies have shown that unnecessary right ventricular pacing has detrimental effects. OBJECTIVE: To evaluate whether minimization of ventricular pacing as compared with standard dual-chamber pacing (DDD) improves clinical outcomes in patients referred for pacemaker or implantable cardioverter-defibrillator (ICD) replacement. METHODS: In an international single-blind, multicenter, randomized controlled trial, we compared DDD with managed ventricular pacing (MVP), a pacing mode developed to minimize ventricular pacing by promoting intrinsic atrioventricular conduction. We included patients referred for device replacement with >40% ventricular pacing, no cardiac resynchronization therapy upgrade indication, no permanent atrial fibrillation (AF), and no permanent complete atrioventricular block. Follow-up was for 2 years. The primary end point was cardiovascular hospitalization. The intention-to-treat analysis was performed by using Kaplan-Meier method and the log-rank test. RESULTS: We randomized 605 patients (556 referred for pacemaker and 49 referred for ICD replacement; mean age 75 ± 11 years; 365 [60%] men, at 7.7 ± 3.3 years from first device implantation) to MVP (n = 299) or DDD (n = 306). We found no significant differences in the primary end point cardiovascular hospitalization (MVP: 16.3% vs DDD: 14.5%; P = .72) and the secondary end point persistent AF (MVP: 15.4% vs DDD: 11.2%; P = .08), permanent AF (MVP: 4.1% vs DDD: 3.1%; P = .44), and composite of death and cardiovascular hospitalization (MVP: 23.9% vs DDD: 20.2%; P = .48). MVP reduced right ventricular pacing (median 5% vs 86%; Wilcoxon, P < .0001) as compared with DDD. CONCLUSIONS: In patients referred for pacemaker and ICD replacement with clinically well-tolerated long-term exposure to >40% ventricular pacing in the ventricle, a strategy to minimize ventricular pacing is not superior to standard DDD in reducing incidence of cardiovascular hospitalizations.

Regional variations in baseline characteristics of cardiac rhythm device recipients: The PANORAMA observational cohort study.

BACKGROUND: The PANORAMA study was designed to collect concurrent data on subjects from different worldwide regions implanted with CRM devices. METHODS: In this prospective, multi-center study, we analyzed baseline data on 8586 subjects implanted with CRM devices with no additional selection criteria (66% pacemaker (IPG), 16% implantable cardiac defibrillators (ICD), 17% cardiac resynchronization therapy (CRT) and < 1% Internal Loop Recorder) from 156 hospitals across 6 geographical regions between 2005 and 2011. RESULTS: Regardless of the device implanted, subjects from the Middle East and India often had more diabetes than other regions. Eastern and Western Europe had higher rates of atrial fibrillation reported, and men were more likely to smoke than women (46% vs 11%, p < 0.001). Within the CRT cohort there was significant variation in the proportion of males receiving a device, ranging from 55% in India to 83% in Eastern Europe. CONCLUSIONS: We provide comprehensive descriptive data on patients receiving CRM devices from a range of geographies that are not typically reported in literature. We found significant variations in clinical characteristics and implant practices. Long term follow-up data will help evaluate if these variations require adjustments to outcome expectations.

Hypothermia-induced Brugada-like electrocardiogram pattern.

A patient in whom moderate hypothermia developed after prolonged cardiopulmonary resuscitation is described. Hypothermia was manifested by transient electrocardiogram changes, including long QT, precordial J waves, and downsloping ST-segment elevation ending in a negative T wave in leads V(1) and V(2) resembling the Brugada syndrome. The physiopathologic mechanisms of these electrocardiographic findings are discussed.

Transient Brugada-type electrocardiographic abnormalities in renal failure reversed by dialysis.

The Brugada syndrome (BRS) is a hereditary cardiac condition (characteristically with a gene mutation affecting sodium channel function) identified by an elevated terminal portion of the QRS complex (prominent J wave) followed by a descending ST-segment elevation ending in a negative T wave in the right precordial leads, and malignant tachyarrhythmias in patients without demonstrable structural heart disease. We report a patient with a previous history of epilepsy treated with psychotropic drugs (with a sodium channel blocking effect) and chronic renal failure on haemodialysis who developed hyperkalaemia (6.6 mmol/l) and ECG findings resembling BRS. This condition was manifested by the prominent J wave, the coved-type ST-segment elevation and the negative T wave in the right precordial leads. These ECG changes disappeared after haemodialysis when the potassium became normal. Subsequently, a flecainide test did not reproduce ST-segment elevation. We conclude that hyperkalaemia associated with cardiac membrane active drugs may cause ECG changes mimicking the Brugada syndrome.