Prospective evaluation of diagnostic work-up in syncope patients: results of the PL-US registry.

AIMS: Syncope is a common problem. Demographic and clinical characteristics of patients admitted to different types of centres may vary, physician's adherence to the guidelines has been examined only in a few studies, and the requirements for implantable loop recorders (ILR) have not been well defined. The aim of this study was to (i) compare demographic and clinical characteristics of patients with syncope diagnosed and treated in tertiary electrophysiology cardiac centres and those attending syncope units or general hospitals, (ii) assess how physicians adhere to the published guidelines, and (iii) calculate the requirement for ILR insertion. METHODS AND RESULTS: In total, 669 consecutive patients with syncope, admitted to 18 electrophysiological cardiac tertiary centres over a mean of 3 months (range 1-10 months), entered a special Internet database called the PL-US (Polish patients with Unexplained Syncope) registry. Detailed demographic and clinical characteristics of the patients, including the results of all diagnostic tests performed, were analysed. Adherence to the guidelines was assessed, based on the published recommendations. The ILR implantation was indicated when (i) all other tests were inconclusive (unexplained syncope) and (ii) syncope associated with injury or presence of organic heart disease or past medical history and ECG suggesting arrhythmic syncope. Syncope of cardiac/arrhythmic origin was the most frequent diagnosis (53%), followed by reflex syncope (33%). Adherence to the guidelines was less than satisfactory-measurement of blood pressure in an upright position, carotid sinus massage, exercise testing, and electrophysiological study were underused, whereas prolonged ECG monitoring and neurological consultations were overused. Unexplained syncope had 58 (9%) patients, and 42 (72%) of them had indication for ILR which accounts for 6% of the whole study population. The calculated need for ILR was 222 implants/million inhabitants/year. CONCLUSION: Patients with syncope admitted to the tertiary electrophysiology cardiac centres are a highly selected group of patients with syncope and differ in their characteristics as well as underlying diseases to those managed at general hospitals, outpatient clinics, or special syncope units. In Poland, the adherence to the published guidelines is far from satisfactory. At least 6% of all consecutive patients with syncope are candidates for ILR insertion.

Retrospective analysis of reasons for failure of DDD pacemaker implantation in patients operated on between 1993 and 2005.

BACKGROUND: During implantation of a DDD pacemaker the following difficulties may be encountered: venous anomalies (the absence of vessels of adequate calibre or difficulty in subclavian vein puncture), arrhythmias during implantation (episodes of atrial flutter/fibrillation while the atrial leads are being positioned), lack of mechanical stability of the electrode in the heart chamber and inability to achieve an acceptable pacing and sensing threshold during implantation. The purpose of the study was to analyse retrospectively the reasons for DDD pacemaker failure in patients operated on between 1993 and 2005. METHODS: We reviewed retrospectively all implantation data from 1988 to 2005 to identify patients with primary failure of DDD pacemaker implantation. Further analysis included patients who had received a DDD pacemaker between 1993 and 2005, when this type of pacemaker made up between 9 and 40% of all pacemaker implantations. We implanted 7469 pacemakers, including 1958 (26.2%) dual-chamber pacemakers, in 783 patients with atrioventricular block (AVB), 392 with sick sinus syndrome (SSS), 450 with AVB +/- SSS and 333 with tachy-brady syndrome (TBS). The mean age of the patients was 65.5 +/- 17.3 years. DDD pacing was unsuccessful in 108 (1.4%) patients, including 32 with AVB, 22 with SSS, 16 with SSS +/- AVB and 38 with TBS. The mean age of these patients was 78.5 +/- 19.4 years. RESULTS: The reasons for failed implantation were venous anomalies in 12%, an arrhythmia episode in 27.8%, a high pacing threshold in the atrium in 17.6%, low atrial potential amplitude in 25.9% and lack of mechanical stability of the electrode in 16.7% of patients. The difficulties were encountered in elderly patients (p < 0.01), most frequently in patients with SSS and TBS (71). Between 2004 and 2005 venous anomalies and a high pacing threshold were the main causes of failure. CONCLUSIONS: Currently the main difficulties encountered during pacemaker implantation are venous anomalies and a high pacing threshold. Arrhythmia episodes, low atrial potential amplitude and lack of mechanical stability are of minor importance. Elderly patients with sick sinus syndrome and tachy-brady syndrome have the highest failure rate. (Cardiol J 2007; 14: 155-159).