Modulation of AMP deaminase in rat hearts subjected to ischemia and reperfusion by purine riboside.

Changes in AMP deaminase (AMPD) activity influence heart function and progression of heart disease, but the underlying mechanism is unknown. We evaluated the effect of purine riboside (Purr) on the activity of AMPD in perfused rat hearts and in isolated rat cardiomyocytes. Brief perfusion of the pre-ischemic heart with 200 micro M Purr resulted in activation of AMPD, more pronounced degradation of the adenine nucleotides, and reduced recovery of the adenine nucleotide pool during reperfusion. Brief incubation of rat cardiomyocytes with 200 micro M Purr also activated AMPD, while prolonged exposure resulted in enzyme inhibition. We conclude that Purr activates AMPD, whereas metabolites of this compound may inhibit the enzyme.

[Is application of electrocardiographic exercise test always usefull in the diagnosis of coronary artery disease? Advantages and limitations of this method]. / Czy zawsze warto wykonywac elektrokardiograficzna próbe wysilkowa w rozpoznawaniu choroby wiencowej? Zalety i organiczenia metody.

UNLABELLED: To determine the diagnostic value of the electrocardiographic exercise testing (EET) in 551 patients with chest pain regarded as definite or probable stable angina pectoris (CAD), results of performed EET were compared with coronary angiography. All patients underwent exercise testing according to the Bruce protocol. The criterion for a positive exercise ST-segment response was > or = 1 mm of horizontal or down sloping depression 80 msec after J-point. The indications for cardiac catheterization in each patient were determined at the discretion of the attending physician. Clinically important coronary artery disease was defined as > 50 per cent narrowing of the diameter of at least one major vessel or > or = 50 per cent of the left main coronary artery. RESULTS: The sensitivity and specificity of EET for detection of CAD were for the entire group, in women and men respectively: 93%, 91%, 94% and 21%, 16%, 27%. CONCLUSION: 1. Indications for EET should be based on prior probability of coronary artery disease. 2. Application of higher than conventional ST depression criteria (> or = 2 mm) lowers sensitivity but increases specificity of EET. 3. Variables determining false positive results are as follows: age, sex (female), low probability of CAD, ST-segment depression in leads: II, III, aVF and mitral valve prolapse. 4. Variables determining false negative results are as follows: high probability of CAD, sex (male) and one vessel disease.

The localisation of the electrode in permanently paced heart--an echocardiographical study.

UNLABELLED: Permanent cardiac pacing is a widely applied procedure in invasive cardiology. The aim of our study was the analysis of the localisation of the tip of the pacemaker lead and its course in the right ventricle. Research was carried out on a group of 12 patients (5F, 7M), from 40 to 93 years of age (average 70 +/- 15 yrs) with permanent cardiac pacing or implantable cardioverter-defibrillator (ICD). Subsequent echocardiographic views were applied: an apical four chamber view, a subcostal one and a parasternal right ventricular inflow tract view. At the level of the tricuspid annulus the electrode was positioned: the anterior leaflet--41.7% (5 pts), the anteroseptal commissure 25% (3 pts), the posterior leaflet 8.3% (1 pt) and the septal one--8.3% (1 pt). In 16.7% (2 patients) the lead was positioned centrally in the right atrioventricular orifice. Regarding the further positioning of the electrode in the ventricle, in 41.7% (5 pts) the leads were placed along the interventricular septum, in 16.7% (2 pts) along the anterior wall of right ventricle and in 41.7% (5 pts) across the centre of the right ventricle. The tip of the lead was positioned in the apex of the right ventricle in 83.4% (10 pts). In the remaining 16.7% (2 pts) the position was not apical--in 1 patient the anterior wall of the right ventricle and in 1 patient the interventricular septum. In the VVI pacing mode the electrode did not lie on the interventricular septum. In contrast to this in 80% of patients (4 pts) having the DDD pacing mode the lead was situated on the interventricular septum on its course downwards to the ventricle. CONCLUSIONS: 1) On the level of the leaflets of the tricuspid valve the lead most often was positioned at the level of the anterior leaflet and the anteroseptal commissure. 2) Most patients had an apical localisation of the tip of the lead. 3) Differences between morphological and echocardiographic studies are related to the intravital and the two-dimensional character of echocardiography, and probably to the small population of the group examined.

[ECHO image quality of the left ventricle during dobutamine stress echocardiography]. / Jakosc obrazu echokardiograficznego w czasie testu obciazeniowego z dobutamina.

This study aimed at assessing ECHO image quality of the left ventricle during dobutamine stress echocardiography (ED). The study involved 582 patients without previous myocardial infarction. Their age ranged from 27 to 74 years, mean age 52 +/- 9. Dobutamine was given in stepwise increasing doses from 5 to 40 mcg/kg per minute. Atropine was added in 253 (43%) cases. The wall motion asynergy was evaluated by left ventricular echo image divided into 16 segments. At least one segment has not been visualised in 5.5% of patients. At the peak dose of administrated dobutamine (> 20 mcg/kg per minute) it increased to 6.1%. Unvisualized segments did not impair the test and did not affect negative or non diagnostic results, as was verified statistically. Patients' age, body weight and BMI did not exert a significant effect on the quality of echo image. Segments 5 and 11 were seen constantly during the whole test. Segment 13 was poorly visualised during the tests. Only in 1.5% of patients peak dose of dobutamine deteriorated the image, especially in segments 1, 3, 6, and 12. During the dobutamine echocardiography test the quality of ECHO image of left ventricular wall was worsening only in a few patients. It was not considered the reason of test interruption and did not impared the results of ED.

[The diagnostic value of resting electrocardiography in stable coronary artery disease]. / Wartosc diagnostyczna spoczynkowego badania elektrokardiograficznego w rozpoznawaniu stabilnej choroby wiencowej.

The relation of resting electrocardiographic (ECG) patterns to angiographic features was assessed in 566 patients with chest pain regarded as definite or probable stable angina pectoris. The indications for catheterization in each patient were determined at the discretion of the attending physician. All patients underwent diagnostic coronary angiography (clinically important coronary artery disease was defined as > or = 70 per cent narrowing of the diameter of at least one major vessel or > or = 50 per cent of the left main coronary artery) and standard 12 lead electrocardiography which was interpreted by 2 cardiologists independently in coordinating centre. The signs of impaired coronary blood flow were assessed by abnormalities of repolarization (among others S-T segment, the T wave), depolarization and presence of disturbances of cardiac rythm. The resting routine electrocardiogram was assigned to one of three categories: normal, nonspecific abnormalities or typical for coronary insufficiency. The typical pattern for ischemia was present in 104 patients (18%), nonspecific abnormalities were present in 185 patients (33%) and electrocardiogram was normal in 277 patients (49%). Sensitivity and specificity of the typical for coronary insufficiency resting ECG was calculated: 23% and 87% respectively for the entire group, 33% and 81% in women, 20% and 93% in men. In the group with normal resting electrocardiographic pattern 55% of patients have significant stenosis in at least one major coronary artery.