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UNLABELLED: Rectilinear biphasic cardioversion (Bi-DC) has been shown to be very effective for restoration of sinus rhythm in patients with persistent atrial fibrillation (AF). There is, however, limited information on factors influencing effectiveness of the initial energy of 50 J for Bi-DC of atrial fibrillation. AIM OF THE STUDY: Evaluation of efficacy of 50 J shock of Bi-DC for restoration sinus rhythm and development of point score system to predict high conversion rate of 50 J shock in persistent atrial fibrillation. MATERIAL AND METHODS: The study group was composed of 502 consecutive Bi-DC in-patients with persistent atrial fibrillation who underwent cardioversion according to the standard protocol (50 J --> 1 J/kg m.c. --> 2 J/kg m.c. --> 200 J). Factors influencing effectiveness of 50 J shock were defined. RESULTS: Rectilinear biphasic cardioversion of shock of 50 J was successful in 157 (31%) patients. In multivariate analysis independent factors associated with efficacy of 50 J shock were: atrial fibrillation duration < 7 months (OR: 14.3, CI: 5.83 - 35.2, p < 0.001), left ventricular ejection fraction--LVEF > 40% (OR: 5.67, CI: 1.22 - 26.3, p = 0.027), body weight < 78 kg (OR: 3.17, CI: 1.52 - 6.59, p = 0.002), permanent pacemaker (OR: 2.98, CI: 1.20 - 7.40, p = 0.018), LA diameter < 4.5 cm (OR: 2.80, CI: 1.19 - 6.58, p = 0.02). A simplified point score system was developed to predict the chance for termination of atrial fibrillation (the score gives 5 points for atrial fibrillation duration < 7 months; 2 points for EF > 40%; 1 point for pacemaker, body weight < 78 kg and LA < 4.5 cm, each). High effectiveness (65%) of 50 J shock was achieved in patients with > 9 points of scoring system and 80% in this group when atrial fibrillation duration is shorter than 3 months. Effectiveness of 50 J shock was very low in the remaining group (0 points--0%; 1-3 points--5%; 4-6 points--21%; 7-8 points--34%, respectively). CONCLUSION: The efficacy of initial shock of 50 J for termination of atrial fibrillation is limited and is not recommended for general population of patients with atrial fibrillation referred for Bi-DC. 50 J might be considered in patients with pacemakers without factors associated with failure of 50 J to terminate atrial fibrillation: atrial fibrillation duration > 7 months, lower LVEF increased LA diameter, body weight > 78 kg. The shock of 50 J is effective in more than 60% of patients, if they achieved 9 or 10 points in proposed score. The highest efficacy of 50 J shock (80%) is possible to reach in this group if atrial fibrillation duration is shorter than 3 months.

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AIMS: To develop a simple point score system that can accurately predict the optimal energy of initial rectilinear biphasic (RLB) waveform shock for cardioversion (DC) of persistent atrial fibrillation (AF). METHODS AND RESULTS: Data from 302 consecutive patients with AF who underwent a step-up protocol of sequential shocks of 50 J-from 1 up to 2 J/kg-200 J of RLB waveform DC were prospectively examined. Using a logistic regression model, three variables independently predicted the need for 2 J/kg shocks: AF duration > 7 months, previous DC, and increased left atrial (LA) diameter > 4.5 cm. A simplified point score system (REBICAF score) that spans from 0 to 4 was developed. The score gives two points for AF duration > 7 months and one point for previous DC or LA diameter > 4.5 cm. The area under the receiver operator curve (ROC) of the proposed score for predicting the need for 2 J/kg shock was 0.84. There was a progressive increase in the need for 1 J/kg, 2 J/kg, and 200 J as the point score increased (P < 0.001, chi2 test for trend). More than 90% cumulative success rate was achieved in the low- (0-1), intermediate- (2), and high-REBICAF (3-4) score subgroups with 1 J/kg, 2 J/kg, and 200 J RLB shocks, respectively. CONCLUSION: A simple point score system is useful in prediction of successful initial RLB energy for DC of AF.

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AIMS: In patients with acute myocardial infarction (MI), low serum triiodothyronine (T3) concentration is commonly associated with a severe clinical course. The aim of this prospective study was to investigate whether a severe clinical course in patients with low T3 is related to the magnitude of myocardial injury assessed by echocardiography. METHODS AND RESULTS: Out of 635 patients with MI we enrolled 100 consecutive patients. They were divided in two subgroups: group A, 81 patients without clinical hard events (death, resuscitation following ventricular tachycardia/vertricular fibrillation, new MI) and group B, 19 patients in whom at least one of the above hard events occurred during hospital stay. Thyroid function tests were performed on day 1, 4 and 7, echocardiographic examinations measuring asynergic area (AA), and wall motion score index (WMSI) between day 1 and 5 (median 3). A negative correlation was found between plasma free triiodothyronine (FT3), concentration and AA (p<0.001), FT3 and WMSI (p<0.001) values at all time points. FT3 concentration was lower in group B than group A at all time points (p<0.001). CONCLUSIONS: In patients with acute MI, low FT3 state is related to the extent of myocardial damage.

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AIMS: A high level of total cholesterol and LDL-cholesterol disturbs the endothelial function. Thus it can be expected, that hypercholesterolaemia may unfavourably influence the course of the acute myocardial infarction. The aim of the study was to check whether patients with lipid levels above normal during the first hours of myocardial infarction have an unfavourable clinical outcome. METHODS AND RESULTS: The study group consisted of 348 patients (216 males, aged 65.7+/-12 years) with acute myocardial infarction hospitalized up to 24 hours after the onset of symptoms. Blood samples for lipid profile were taken on the first day of hospitalization, in the morning, while fasting. 109 (31%) patients had a complicated in-hospital course of infarction (i.e. death, recurrent ischaemia, serious arrhythmias and/or conduction disturbances, heart failure). The total cholesterol and LDL-cholesterol levels were higher in the patients with complicated than in the patients with uncomplicated clinical course of infarction: 243+/-40.7 vs 211.2+/-40.6 mg/dl, p<0.001 and 156+/-35.0 vs 132.6+/-35.2 mg/dl p<0.001, respectively. CONCLUSIONS: Higher levels of total cholesterol and LDL cholesterol during the first 24 hours of acute myocardial infarction have a strong negative prognostic value, what suggests the use of statins as early as possible in acute myocardial infarction.

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BACKGROUND: Cardiac arrhythmia is often present in patients with acute coronary syndrome (ACS) and may be due to the electrolyte imbalance. AIM: To assess the prevalence and clinical significance of electrolyte imbalance in ACS. METHODS: Serum potassium and magnesium levels were measured within the first few hours in 204 consecutive patients with ACS admitted to our department over a period of 23 months. Cardiac arrhythmia was documented using continuous ECG monitoring, telemetry or standard ECG. RESULTS: Hypokalemia was observed in 34% of patients, and was significantly associated with the occurrence of life-threatening ventricular arrhythmias (26% of patients with potassium level <4 mmol/l vs 11.9% of patients with normokalemia, p<0.001). No relationship was found between potassium level and supraventricular arrhythmias or in-hospital mortality. Decreased magnesium serum concentration was found in 22% of patients but was not significantly associated with cardiac arrhythmias or mortality. CONCLUSIONS: Hypokalemia and hypomagnesemia are often present in patients with ACS. The former is associated with dangerous ventricular arrhythmias. Early assessment of electrolyte serum concentration is needed in order to implement proper supplementation.

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BACKGROUND: In a clinical setting of acute myocardial infarction (MI), short-lasting and transient anginal pain, preceding the development of acute MI, is regarded as a symptom representing ischaemic preconditioning. Some experimental and clinical data suggested that preinfarction angina may favourably influence the course of acute MI. AIM: We sought to examine the hypothesis that preinfarction angina occurring within 24 hours prior to the onset of acute MI favourably influences the outcome. METHODS: The study group consisted of 331 patients who were admitted to our hospital due to acute MI with ST segment elevation with a symptom duration <12 hours and received thrombolysis. Preinfarction angina within 24 hours prior to MI was present in 80 patients whereas the remaining 251 patients had no chest pain preceding acute MI. The course of the in-hospital phase of MI (mean 15 days) was analysed. RESULTS: In patients with preinfarction angina the in-hospital complication rate was significantly lower than in patients without angina preceding acute MI (p<0.001). Patients without preinfarction angina more frequently developed heart failure (p<0.001) or died (p<0.01) in hospital. Patients with preinfarction angina had significantly less extensive MI and had reperfusion symptoms more frequently. Multivariate analysis showed that there were three factors which independently favourably influenced survival: preinfarction angina (p=0.01), age < or =65 years (p=0.04) and duration of chest pain during acute MI < or =3h (p=0.03). Of the analysed group, 73 patients died in hospital. The independent variables predicting death included prior MI (p=0.04), history of diabetes (p=0.02), acute left bundle branch block (p=0.01) and age >65 years (p=0.03). Non-fatal re-infarction complicated the in-hospital course of MI in 27 patients. The independent variables which predicted this complication included age >65 years (p=0.03) and hypercholesterolemia (p=0.04). CONCLUSIONS: Patients with preinfarction angina, occurring within 24 hours of acute MI, have better in-hospital outcome and less extensive myocardial injury than patients without antecedent angina. These results may be attributed to the protective effects of ischaemic preconditioning.

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BACKGROUND: Acute coronary syndrome (ACS) carries the risk of death due to electrical or haemodynamical disturbances. Thus, rapid in-hospital treatment is necessary. To achieve this, a patient, his family and his physician should correctly diagnose ACS, based mainly on clinical symptoms. AIM: To assess the symptomatology of ACS and to establish whether modern management of ischaemic heart disease did not change ACS clinical characteristics. METHODS: The study group consisted of 156 consecutive patients (96 males, mean age 65+/-15 years) admitted to hospital due to ACS. Physicians prospectively filled in a questionnaire addressing ACS symptomatology, including chest pain characteristics and clinical symptoms of painless ACS. RESULTS: Retrosternal chest pain was present in 119 (76%) patients, six (4%) patients had pain localised outside thorax (jaws or epigastric region) whereas 31 (20%) patients had painless ACS. In the latter group the most frequent symptoms were dyspnea and marked weakness. CONCLUSIONS: Chest pain remains the most frequent symptom of ACS and its prevalence is similar to that previously described in literature. Almost a quarter of patients have painless ACS; in those patients other intensive and sudden symptoms may suggest ACS.