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BACKGROUND: Many patients with stable coronary artery disease (CAD) have no visual segmental wall motion abnormalities and a left ventricular (LV) ejection fraction (LVEF) ≥ 50% at rest despite significant coronary artery stenosis. Here, the aim was to determine the impact of percutaneous coronary intervention (PCI) on LV function assessed by enhanced echocardiography in patients with stable CAD with or without diabetes mellitus type 2 and a preserved LVEF. METHODS: Sixty-six consecutive patients with CAD and LVEF ≥ 50%, admitted to the hospital for planned coronary angiography, were prospectively assessed. PCI was performed for coronary artery stenosis > 70%. CAD extent was assessed using SYNTAX and EXTENT scores. To assess LV function, LVEF, global longitudinal strain (GLS), and LV peak systolic myocardial velocity (S') were measured and Tei index was calculated before and 3 months after PCI. RESULTS: Before PCI, LVEF, GLS, and Tei index were significantly worse in diabetic patients. LV functional indices improved significantly after PCI in all patients (p < 0.001). Multivariate linear regression analyses were performed to evaluate the impact of selected factors on LV function after PCI expressed as changes (D) of LVEF, GLS, S', and Tei index. LV function improvement expressed as DGLS was associated only with SYNTAX score. Higher SYNTAX scores were related to greater GLS improvement (b = 0.003, 95% confidence interval: 0.0004-0.005; p = 0.02). CONCLUSIONS: Percutaneous coronary intervention significantly improved LV function in diabetic and non-diabetic CAD patients with preserved LVEF. Enhanced echocardiography allowed an assessment of subtle changes in LV function.

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Electrocardiographic (ECG) exercise stress test has been a major diagnostic test in cardiology for several decades. Ongoing technological advances that have led to a wide use of imaging techniques and development of new guidelines have called for a revised and updated approach to the technique and interpretation of the ECG exercise testing. The present document outlines an expert opinion of the Polish Cardiac Society Working Group on Cardiac Rehabilitation and Exercise Physiology regarding the performance and interpretation of ECG exercise testing in adults. We discussed technical requirements and necessary equipment for the exercise testing laboratory as well as healthcare personnel competencies necessary to supervise ECG exercise testing and fully interpret test findings. Broad indications for ECG exercise testing include diagnostic assessment of coronary artery disease (CAD), including pre-test probability of CAD, evaluation of functional disease severity and risk strati- fication in patients with established CAD, assessment of response to treatment, evaluation of exercise-related symptoms and exercise capacity, patient evaluation before exercise training/cardiac rehabilitation, and risk stratification prior to non-cardiac surgery. ECG exercise testing is safe if indications and contraindications are observed, testing is appropriately monitored, and indications for test termination are clearly established. The exercise protocol should be adjusted to the expected exercise capacity of a patient so as to limit the duration of exercise to 8-12 min. Clinical, haemodynamic, and ECG response to exercise is evaluated during the test. The test report should include information about the exercise protocol used, reason for test termination, perceived exertion, presence/severity of anginal symptoms, peak exercise capacity or tolerated workload in relation to the predicted exercise capacity, heart rate response, and the presence or absence of ST-T changes. The test report should conclude with a summary including clinical and ECG assessment.

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BACKGROUND: In patients with non-ST segment elevation acute coronary syndromes (NSTE-ACS), the long-term risk of deathand myocardial infarction (MI) is estimated by scores based on noninvasively derived variables. Much less is known about the relation between the degree of atherosclerotic burden in the coronary tree and the long-term risk of patients with NSTE-ACS. AIM: To evaluate the accuracy of a wide spectrum of coronary angiographic and clinical data in predicting outcomes ina long-term follow-up of patients successfully treated invasively for NSTE-ACS. METHODS: The study group consisted of 112 consecutive patients (age 62 ± 10 years; 76 men) treated invasively for NSTE-ACS.27 (24%) patients had a history of diabetes mellitus (DM) and 37 (33%) patients a history of MI. The coronary angiograms priorto intervention were evaluated blindly for the four angiographic scores: (1) Stenosis score derived from the assessment of thedegree of stenosis in 15 segments of the coronary tree; (2) Vessel score showing the number of main vessels stenosed > 70%; (3) Extensity score assessing the proportion of lumen length irregularity in 15 segments; and (4) Complexity score describingthe number of complex plaques. The angiographic analysis also focused on the flow, presence of thrombus and collateralsupply prior to intervention (according to TIMI) and the size of the culprit lesion vessel. The intervention was successful in 95% of cases. All patients were followed-up for 6-24 months for the occurrence of death or MI. RESULTS: In the follow-up period, the composite end point of death or MI occurred in 20 (17%) patients. In order to indicate therisk predictors from the group of clinical and angiographic variables (age, sex, history of DM, history of MI, four angiographicscores and culprit lesion vessel characterisation), logistic regression analysis was performed. The independent angiographic predictors of composite end point (selected by forward conditional selection) were stenosis score (OR 1.13; 95% CI 1.05-1.2;p < 0.001) and size of the vessel (OR 0.08; 95% CI 0.01-0.6; p = 0.02). CONCLUSIONS: Our preliminary data shows that attempting to add angiographic variables into the risk assessment scoring systems in order to strengthen their predictive accuracy is justified.

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BACKGROUND: Shortening the time delay at the beginning of treatment in ST-segment elevation myocardial infarction (STEMI) has proven to be clinically essential. Invasive vs. thrombolytic treatment strategy is currently under investigation, particularly in terms of the time from the onset of symptoms to treatment initiation. It is likely that enrolment to trials in STEMI may paradoxically prolong the time delay to treatment if randomisation procedures are too complex. AIM: To evaluate time to the onset of reperfusion therapy (door-to-thrombolysis time - DtT) in patients randomised to trials (TT) or treated routinely with thrombolytics (Thrx). METHODS: We evaluated DtT in a group of 189 consecutive STEMI patients (TT: n = 96; Thrx: n = 93). The inclusion criteria for the analysis were identical in both groups: 1. STEMI diagnosis was given on admission. 2. Patients had no signs of heart failure. 3. Patients did not require any additional therapy prior to thrombolysis (no need for electrical cardioversion or blood pressure lowering). 4. There were no contraindications for immediate reperfusion therapy. The comparison of DtT between evaluated groups was performed. To find out the independent predictors of DtT prolongation, the impact of patients' age, gender, admission time, pre-hospital delay and trial participation has been evaluated in multivariate analysis. RESULTS: Highly statistically longer mean value of DtT was measured in the entire TT group than in Thrx (41 ± 18 vs. 22 ± 8 min; p 〈 0.001). The difference was also significant for patients who constituted the subgroup of TT who were proposed and refused to participate in trials (37 ± 13 vs. 22 ± 8 min; p 〈 0.01). No differences in DtT were found between groups of patients enrolled to various trials. The participation in TT was found to be the strongest predictor of DtT prolongation over 30 min (OR 13.2; 95% CI 6.1-28.5; p 〈 0.001). The risk of over 30 min DtT prolongation was five times higher if patients were admitted in an early phase of the trial. CONCLUSIONS: 1. Participating in trials delays the beginning of reperfusion therapy. 2. This delay may be clinically important, particularly in patients hospitalised in a very early phase of STEMI. 3. The call for reappraisal of informed consent issues and randomisation procedures in the context of simplicity seems to be justified.

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BACKGROUND: Right ventricular (RV) involvement increases mortality and morbidity in inferior myocardial infarction (MI). There are sparse data on the usefulness of pulsed tissue Doppler imaging (TDI) in the diagnosis of RV dysfunction in ST segment elevation MI (STEMI) treated by primary percutaneous coronary intervention (pPCI). AIM: To evaluate the diagnostic and prognostic significance of RV myocardial velocities compared to classical electrocardiographic RVMI diagnostic criteria in this group of patients. METHODS: Consecutive patients with first, acute, inferior STEMI treated with pPCI were prospectively assessed. The RVMI was defined as an ST-segment elevation ≥ 0.1 mV in lead V4R. Echocardiography with TDI was performed after pPCI within 24 h of the onset of symptoms. Follow up including in-hospital events was performed. RESULTS: Out of 101 patients (58 males, mean age 63.7 ± 11.1 years), RVMI was found in 37 (37%). In multivariate analysis, peak systolic RV velocity (SmRV) (OR 5.12), peak early diastolic RV velocity (EmRV) (OR 5.03) and RV wall motion abnormalities (OR 4.94) were independent parameters for RVMI diagnosis. Receiver operating characteristics revealed high diagnostic significance of SmRV (C statistics = 0.90) and EmRV (C statistics = 0.89). The SmRV < 12 cm/s as a cut-off for a diagnosis of RVMI had a 89% sensitivity and a 83% specificity, whereas EmRV < 10 cm/s - 81% and 80%, respectively. Multivariate analysis showed that two variables - SmRV and ST-segment elevation ≥ 0.1 mV in lead V4R, were independent predictors of in-hospital prognosis. CONCLUSIONS: Right ventricular myocardial velocities derived from TDI predict ECG diagnosis of RVMI with relatively high sensitivity and specificity. Their high negative predictive value may be of practical importance when ECG tracings are equivocal. More importantly, decreased RV systolic myocardial Doppler velocity predicts unfavourable clinical outcomes in patients with inferior STEMI independently of ECG changes.

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A case of a 50 year-old woman with unstable angina is presented. During the exercise test performed at 5th day of hospitalisation T wave normalisation in leads III, aVF, V4-V6 was observed. The subsequent angiography revealed critical stenosis of the right coronary artery and percutaneous coronary intervention was performed. Following intervention there were no T wave changes during exercise.

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BACKGROUND: There is significant evidence that reactive oxygen species play an important role in endothelial dysfunction, ischemia/reperfusion injury as well as in the pathogenesis of diabetes mellitus (DM). It is also known that vitamins C and E have substantial antioxidant properties. However, clinical evidence concerning this topic is insufficient so far. The aim of the present study was to determine if the administration of vitamins C and E influences the outcome in diabetic patients with acute myocardial infarction (AMI). METHODS: Among 800 patients with AMI included in the MIVIT (Myocardial Infarction and Vitamins) study, 122 patients (15%) had confirmed DM. A retrospective analysis of the influence of vitamins C and E on 30-day cardiac mortality in patients with or without DM was performed. RESULTS: There was a significant reduction in 30-day cardiac mortality in diabetic patients treated with antioxidant vitamins C and E [5 (8%) vs. 14 (22%); OR 0.32, 95% CI 0.11-0.93; p = 0.036]. Such an effect has not been observed in patients without DM [19 (6%) vs. 19 (6%); OR 0.97, 95% CI 0.51-1.85; p = 0.94]. CONCLUSION: The results suggest that early administration of antioxidant vitamins C and E in patients with AMI and concomitant DM reduces cardiac mortality.

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AIMS: There is a large body of evidence that reactive oxygen species (ROS) produced during myocardial ischemia and reperfusion play a crucial role in myocardial damage and endothelial dysfunction. The MIVIT pilot trial was designed to test the effects of antioxidant vitamins C and E on the clinical outcome of patients with AMI. METHODS AND RESULTS: In this randomized, double-blind, multicenter trial, 800 patients (mean age 62) with AMI were randomly allocated to receive, on top of routine medication, one of two treatments: vitamin C (1000 mg/12 h infusion) followed by 1200 mg/24 h orally and vitamin E (600 mg/24 h) or matching placebo for 30 days. Primary end point (composite of in-hospital cardiac mortality, non-fatal new myocardial infarction, VT/VF/asystole, shock/pulmonary edema) occurred less frequently in patients treated with antioxidants (55 [14%] vs 75 [19%], OR 0.82 [95% CI, 0.68-1.00], p=0.048). CONCLUSIONS: This randomized pilot trial shows that supplementation with antioxidant vitamins is safe and seems to positively influence the clinical outcome of patients with AMI. A larger study is warranted to provide further evidence of this promising and inexpensive regimen.

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AIMS: L-arginine is a substrate for nitric oxide (NO) synthesis in vascular endothelial cells. NO bioavailability is decreased during myocardial infarction (MI). It might be expected that administration of L-arginine may maintain NO production and alleviate the course of MI. The aim of the study was to assess safety and effects of treatment with L-arginine on the clinical course of MI. METHODS AND RESULTS: 792 patients (mean age 64 years, 551 men) with ST segment elevation MI admitted within 24h after the onset of symptoms were randomized to oral L-arginine (3.0 t.i.d p.o. for 30 days) or placebo on top of routine therapy. The end point which was the composite of 30 day cardiovascular death, reinfarction, successful resuscitation, shock/pulmonary edema or recurrent myocardial ischemia occurred in 24% patients treated with L-arginine and 27% with placebo (OR 0.63, 95% CI 0.39-1.02, p=0.06). The end point was observed less frequently in 226 patients with hyperlipidemia (19 vs 31, p<0.05). No serious adverse effects were observed during L-arginine supplementation. CONCLUSIONS: This study, which is the first attempt to use L-arginine in MI, showed that oral L-arginine supplementation was well tolerated. Beneficial nonsignificant trend was observed towards reduction of major clinical events.

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BACKGROUND: In congestive heart failure (CHF), endothelial dysfunction may contribute to impairment of exercise induced vasodilatation and decreased exercise capacity. We hypothesised that administration of L-arginine, a precursor of nitric oxide (NO) and postulated antioxidant, may improve endothelium-dependent vasodilatation and exercise capacity and also exert antioxidant activity. AIMS: To investigate the effect of oral supplementation with L-arginine on exercise capacity and markers of oxidative stress in patients with mild to moderate CHF. METHODS: The study had a randomised double-blind cross-over design. Twenty one patients with stable NYHA II-III CHF underwent three exercise tests: initially, after oral administration of L-arginine (9 g/day for 7 days) or placebo. Blood was sampled prior to each test for plasma lipid peroxides, reduced sulphydryl groups and leukocyte oxygen free radical production. RESULTS: We found a higher prolongation of exercise duration time after L-arginine than after placebo (99+/-106 vs 70+/-99 s, p<0.05). There were no significant differences in markers of free radical activity. CONCLUSIONS: In patients with chronic stable CHF, oral supplementation with L-arginine prolongs exercise duration which may be due to NO-induced peripheral vasodilatation. The antioxidant properties of L-arginine have not been confirmed in this ex vivo study.

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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: Electrocardiographic exercise tests are widely recommended for patients before discharge after myocardial infarction, what justify the search for new variables which may improve their prognostic value. QT dispersion in 12 lead ECG reflects the heterogeneity of ventricular repolarisation. Increased QT dispersion is a noninvasive marker of ischaemia and electrical instability. AIM: Evaluation of the prognostic value of exercise-induced changes of QT dispersion in patients after an acute myocardial infarction. METHODS: Heart rate limited treadmill exercise test according to modified Bruce was performed 14+/-5 days after infarction in 77 patients (age 56+/-11,8 female). QT dispersion was measured at rest and on peak exercise. Patients were followed up for mean 88 months. RESULTS: QT dispersion was higher at peak exercise in those patients who died due to cardiovascular causes (n=8) or suffered from non-fatal myocardial infarction during follow-up (n=15), than in remaining group (71+/-20 vs 58+/-22 msec, p<0.01). At rest QT dispersion was similar in both groups (64+/-17 vs 66+/-20 msec, NS). CONCLUSIONS: The lack of an exercise-induced decrease in QT dispersion identifies a subgroup of patients after myocardial infarction with a poor long-term prognosis.

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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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