Permanent pacemaker implantation in unexplained syncope patients with electrophysiology study-proven atrioventricular node disease.

OBJECTIVE: Syncope, whose cause is unknown after an initial assessment, has an uncertain prognosis. It is critical to identify patients at the highest risk who may require a pacemaker and to identify the cause of recurrent syncope to prescribe proper therapy. The aim of this study was to evaluate the effect of permanent pacing on the incidence of syncope in patients with unexplained syncope and electrophysiology study (EPS)-proven atrioventricular (AV) node disease. METHODS: This was an observational study based on a prospective registry of 236 consecutive patients (60.20 ± 18.66 years, 63.1% male, 60.04 ± 9.50 bpm) presenting with recurrent unexplained syncope attacks admitted to our hospital for invasive EPS. The decision to implant a permanent pacemaker was made in all cases by the attending physicians according to the results of the EPS. A total of 135 patients received the antibradycardia pacemaker (ABP), while 101 patients were declined. RESULTS: The mean of reported syncope episodes was 1.97 ± 1.10 (or presyncope 2.17 ± 1.50) before they were referred for a combined EP-guided diagnostic and therapeutic approach. Over a mean follow-up of approximately 4 years (49.19 ± 29.58 months), the primary outcome event (syncope) occurred in 31 of 236 patients (13.1%), and 6 of 135 (4.4%) patients in the ABP group as compared to 25 of 101 (24.8%) in the no pacemaker group (p < 0.001). CONCLUSION: Among patients with a history of unexplained syncope, a set of positivity criteria for the presence of EPS-defined AV node disease identifies a subset of patients who will benefit from permanent pacing.

Permanent pacemaker implantation in unexplained syncope patients with borderline sinus bradycardia and electrophysiology study-proven sinus node disease.

BACKGROUND: Significant sinus bradycardia (SB) in the context of sinus node dysfunction (SND) has been associated with neurological symptoms. The objective was to evaluate the effect of permanent pacing on the incidence of syncope in patients with rather mild degrees of SB, unexplained syncope, and "positive" invasive electrophysiologic testing. METHODS: This was an observational study based on a prospective registry of 122 consecutive mild SB patients (61.90 ± 18.28 years, 61.5% male, 57.88 ± 7.73 bpm) presenting with recurrent unexplained pre and syncope attacks admitted to our hospital for invasive electrophysiology study (EPS). Τhe implantation of a permanent antibradycardia pacemaker (ABP) was offered to all patients according to the results of the EPS. Eighty patients received the ABP, while 42 denied. RESULTS: The mean of reported syncope episodes was 2.23 ± 1.29 (or presyncope 2.36 ± 1.20) in the last 12 months before they were referred for a combined EP guided diagnostic and therapeutic approach. Over a mean follow-up of approximately 4 years (50.39 ± 32.40 months), the primary outcome event (syncope) occurred in 18 of 122 patients (14.8%), 6 of 80 (7.5%) in the ABP group as compared to 12 of 42 (28.6%) in the no pacemaker group (P = .002). CONCLUSIONS: Among patients with mild degree of SB and a history of unexplained syncope, a set of positivity criteria for the presence of EPS defined SND after differentiating reflex syncope, identifies a subset of patients who will benefit from permanent pacing.

Comparison of prognostic risk scores after successful primary percutaneous coronary intervention.

BACKGROUND: The aim of this study was to compare the predictive ability of clinical risk scores (ACEF, EuroSCORE and EuroSCORE II) to angiographic (SYNTAX score) and combined risk scores (Global Risk Score and Clinical SXscore) towards cardiovascular death and/or major adverse cardiac events (MACE) in patients with ST-segment elevation acute myocardial infarction (STEMI) managed with primary percutaneous coronary intervention (pPCI). METHODS: A total of 685 patients successfully treated with pPCI were evaluated and the risk scores were calculated. The primary endpoint was the 2-year incidence of fatal cardiac events. Secondary end points were target lesion failure (TLF), repeat revascularization (RR) and MACE. RESULTS: Patients distributed in the highest tertile of EuroSCORE II presented increased rates of CV death (CVD), all-cause mortality and MACE (p<0.001 for all). EuroSCORE II was associated with increased C-statistics (0.873, 95% CIs: 0.784-0.962 and 0.825, 95% CIs: 0.752-0.898 respectively) for predicting CVD and MACE over competing risk scores (p<0.05). EuroSCORE II conferred incremental discrimination (Harrell's C, p<0.05 for all, apart from CSS for predicting CVD) and reclassification value (Net Reclassification Index, p<0.05 for all, apart from CSS for reclassifying MACE) over alternative risk scores for study's main endpoints. EuroSCORE II independently predicted CVD (HR=1.06, 95% CIs: 1.03-1.09, p<0.001) and MACE (HR=1.07, 95% CIs: 1.04-1.10, p<0.001). CONCLUSION: EuroSCORE II has the best predictive ability of CVD and/or MACE after successful pPCI for the treatment of STEMI.