[Ventricular arrhythmias and the ATc index in patients with ischemic heart disease]. / Komorowe zaburzenia rytmu serca a wskaznik QTc u chorych z choroba niedokrwienna serca.

In this multicenter study a group of 1,011 patients (233 females and 778 males, aged 23-68 years, mean 53) with ischaemic heart disease was included. Only nitrates, nifedipine and diuretics were administered during the investigation. Presence of other chronic disease excluded the patients from study group. In all patients a standard 12-lead electrocardiogram was obtained, from which the QT interval was measured, and its corrected value according to the Bazett's formula calculated [formula: see text] values greater than 440 ms were regarded to be abnormal. A 24-hour ecg ambulatory monitoring was also performed in each patient, and the detected ventricular ectopic activity was classified using the Lown's criteria. Mean QTc values were compared between each class of ventricular arrhythmia. No significant differences were disclosed. All the means were below 440 ms. Also the percentages of patients with a prolonged QTc were similar for all Lown classes of arrhythmia. The patients were then divided into two larger groups: Those with low grade (class 0-2) and high grade (class 3-5) arrhythmia. The portion of patients with the pathologic QTc was not significantly different (21% vs. 28%, NS). Such incidence of QTc prolongation was described for clinically healthy population. Since a 24-hour ecg fails to disclose the entire spectrum of arrhythmia in each individual, the fraction of patients with documented VT/VF in the past was analyzed separately. This subgroup was characterized by more frequent occurrence of QTc prolongation than other patients (35% vs. 20%, p = 0.043). Thus, no firm relationship was found between QTc prolongation and ventricular arrhythmias, but increased QTc favoured the occurrence of VT/VF.

[Unstable coronary disease--clinical course and significance of exercise tests in patients with left coronary artery stenosis]. / Niestabilna choroba wiencowa--obraz kliniczny i wartosc próby wysilkowej u chorych ze zwezeniem pnia lewej tetnicy wiencowej.

This study aimed at evaluating predictive value of exercise tests in case of left coronary artery stenosis. The study involved 57 patients with left coronary artery stenosis, including 10 patients with isolated left main stenosis (group X), and 47 patients with left coronary artery stenosis and multivessel involvement (group Y). Unstable angina was staged according to Booth et al. classification as type I or II. Exercise tests were performed according to Bruce's protocol. Unstable angina of type I was diagnosed in 51 (89%) patients, and type II in 6 (11%) patients. Electrocardiographic evidence of myocardial ischemia both et rest and anginal pain was seen in 46 (80%) patients. Electrocardiographic recording was within normal limits in 11 (20%) patients at rest. Clinical and ECG improvement was seen in 38 (66%) patients. Exercise tests in all of these patients were positive at low load work--mean 50 W. The obtained results suggest that patients with left coronary stenosis constitute heterogenous group. Therefore, prediction of the left main stenosis on the clinical ground alone is impossible. Exercise tests producing positive results at low load indicate with high probability critical multivessel lesions and/or left main stenosis in such patients.

Myocardial perfusion scintigraphy with thallium-201 for prediction of graft patency early after internal mammary artery graft surgery.

Myocardial perfusion scintigraphy with thallium-201 was performed in fifty-four patients after internal mammary artery (IMA) graft to the left descending coronary artery to determine the influence of the flow rate in the IMA on myocardial perfusion after the procedure. The flow rate in the IMA was 40 to 200 ml/minute (mean 103 +/- 26.6 ml/min). Myocardial perfusion after IMA surgery was good in 44 patients (82%). There was a correlation between IMA flow rate and surgical results. Only 53% of patients with IMA flow rates below 100 ml/min to atmosphere showed good myocardial perfusion.