An increasing number of pacemaker implantations create a need for new electrophysiology centres. This paper aims to answer the question whether a newly created electrophysiology centre ensures the same level of safety as7a reference centre in terms of early and late complications of pacemaker implantation. It also makes an attempt to determine whether the outpatient care of patients with an implanted pacemaker is as competent as in a reference centre.MATERIALS AND METHODSThe study is a retrospective non-randomized analysis of the patients who underwent implantation of a permanent single or dual-chamber pacemaker at the Department of Cardiology of the Ludwik Rydygier Provincial Specialist Hospital in Krakow compared to the patients who underwent the same sort of implantation performed at the same time in the reference centre of the third degree at the Department of Clinical Electrocardiology of the John Paul II Specialist Hospital in Krakow. Additionally, the analysis included the outpatient control of the same patients in the period from a minimum of 1.5 to a maximum of 6 years. Patients were divided into two groups: the first group consisted of patients with a single-chamber VVI pacemaker. The second group included patients with a dual-chamber DDD pacemaker. Next, each group was separately analyzed during two periods: hospitalization (223 patients with a VVIR pacemaker, women=119, men=104, under 40 years old 1 patient 0.4%, 41-60 years old 8 patients 3.6%, 61-80 years old 150 patients 67.3%, 81-90 years old 59 patients 26.5%, over 90 years old 5 patients 2.2%) and 52 patients with a DDDR pacemaker (women=21, men=31, under 40 years old 0 patients, 41-60 years old 5 patients 9.6%, 61-80 years old 42 patients 80.8%, 81-90 years old 5 patients 9.6 %, over 90 years old 0 patients) in the Rydygier Hospital and 60 randomly selected patients with a VVIR pacemaker (women=25, men=35, under 40 years old 1 patient 3.3%, 41-60 years old 15 patients 25%, 61-80 years 37 patients 61.7%, 81-90 years old 5 patients 8.3%, over 90 years old 1 patient 1.7%) and 20 patients with a DDDR pacemaker in the reference hospital (women=10, men=10, under 40 years old 1 patient 5%, 41-60 years old 6 patients 30%, 61-80 years 13 patients 65 %, 81-90 years old and over 90 years 0 patients). Outpatient control included (60 patients with a VVIR pacemaker and 20 with a DDDR pacemaker in the L. Rydygier Hospital) and 60 patients with a VVIR pacemaker and 20 patients with a DDDR pacemaker in the John Paul II Hospital.Data was obtained based on the analysis of:1. Cards of eligibility for the treatment; ; 2. Operational protocols from the surgery book;3. ECG records during hospitalization and the long-termfollow-up;4. Descriptions of X-ray pictures taken duringhospitalization;5. Patient medical information letters;6. Archival medical information letters;7. Outpatient medical information letters from thefollow-up of patients with pacemakers.The following data was analyzed in patients assigned to acertain group: gender, age, length of hospitalization, type ofpacemaker, type of electrode, place of pacing, indicationsfor permanent pacing, co-existing diseases, periproceduralcomplications, early complications, late complications,technique of electrode implantation and the type of electrodefixation.A 24-hour period after pacemaker implantation wasthoroughly controlled (patient’s condition, ECG, electricalparameters of stimulation). The following pacemakercontrol parameters were analyzed during the follow-up: thestimulation threshold of atrial or ventricular electrode,sensing in the atrial or ventricular channel, impedance of anatrial or ventricular electrode, the percentage of atrial orventricular stimulation, battery life (in months) and thecompliance with the follow-up schedule. Quantitative traitssuch as age, duration of hospitalization and patient controlparameters were described using arithmetic mean ( x ),standard deviation (s), median (Me), minimum (Min) andmaximum (Max). Differences between hospitals or patientswith and without complications in terms of the analyzedquantitative traits were verified using the Student's t-test orMann-Whitney test. Qualitative characteristics were verifiedusing the chi-square test or Fisher's exact test. The impact ofage on the length of hospitalization was assessed using theSpearman coefficient (rs). Multivariate risk factors analysisfocused on the complications that appear up to three monthsafter surgery. For this purpose, logistic regression withstepwise characteristics elimination was used.Complications were adopted as the dependent Y variabledichotomy type. Calculations were done using the statisticalpackage STATISTICA. A database was created usingMicrosoft Office Excel. Statistical hypotheses were verifiedat a significance level =0.05.RESULTSPatients who underwent implantation of a single or dual ; chamber pacemaker in the provincial centre were hospitalized longer than those treated in the reference centre (the average stay in the provincial hospital for a patient with VVI pacemaker was six days vs. on average 4 days for the reference centre, p<0.001). The technique of subclavian venipuncture used to implant the endocardial electrode was more common in the provincial hospital (61.9% vs. 46.7%, p=0.034). In addition, in 100% of cases, the provincial centre used the passive electrode attachment. It was clearly demonstrated that the number of both early and late (3 months after procedure) complications after implantation of a single or dual-chamber pacemaker in the less experienced centre was not significantly statistically different from the number of complications reported in the reference centre. It has been proven that the technique of electrode implantation has a statistically significant effect on the number of complications (OR=0.11, CI=0.02-0.91, regression coefficient=-2.16, p<0.04). Subclavian venipuncture was associated with a statistically significantly higher incidence of pneumothorax as an implantation complication (p<0.019). However, the type of pacemaker, electrodes or indication for implantation did not have a statistically significant influence on the complications. Moreover, it has been shown that patients with ischemic heart disease and myocardial infarction are the most exposed to the complications mentioned above (OR=3.73, CI=1.13-12.3, regression coefficient=1.32, p<0.03). During the follow-up period, the Rydygier Hospital reported a significantly higher threshold of stimulation 24 hours after VVI implantation (p=0.004).The schedule was not fully executed in both centres in terms of all planned visits. Out of 15 planned check-ups, only 9 took place on average. All check-ups at the provincial clinic were carried out by a physician who used suitable programmers. Most visits in the reference centre were carried out by a technician who used the „IMPULS-BIS” set. There were significantly greater differences (R) in terms of sensing between the maximum and minimum in a patient with VVI pacemaker in the John Paul II Hospital than in the Rydygier Hospital (p=0.048). The mean difference in sensing in the John Paul II Hospital was 4.6 (Me=3.8), whereas in the Rydygier Hospital 3.3 (Me=1.9). There were no statistically significant "fluctuations of sensing, stimulation threshold or impedance" both in the atrial and ventricular channel in patients under the care of provincial ; cardiological clinic and the reference centre. Pacemaker implantation costs were directly connected with the duration of hospitalization (which was longer in the provincial centre) and the number of complications.CONCLUSIONS1. Implantations of single and dual-chamber pacemakers performed in the newly created electrocardiology center in the Rydygier Hospital had a number of complications comparable to the reference centre.2. The selection of patients in terms of qualification to a certain pacing mode in most cases was adequate and similar in both centres.3. Outpatient care of patients with a pacemaker implanted in the cardiological provincial clinic was as competent as in the reference centre. At the provincial outpatient clinic, all check-ups were carried out by a trained physician who used appropriate programmers.4. Implantations performed in the newly created centres, where doctors do not yet have sufficient experience in electrotherapy and carry out a small amount of procedures per year should be done by experienced "teachers" transferred from reference centres or under their direct supervision.5. Outpatient monitoring of a patient with a pacemaker may be conducted by an experienced technician provided that an electrocardiologist is available.6. Check-ups of patients with pacemakers should be thoroughly recorded with every single time reporting of patient's intrinsic rhythm, dependence on stimulation, battery life, electrode impedance, percentage of stimulation and basic parameters of stimulation (threshold, sensing, impedance). This will allow physicians to track the trends of pacing system stability and optimize stimulation parameters.7. Pacemaker implantation costs are directly connected with the duration of hospitalization, which is a derivative of potential periprocedural and early complications.