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R Blasini

Publications and source records attributed to R Blasini.

9 recordsLinked to original sources

[Intravascular ultrasound (IVUS): the assessment of tumor infiltration into the vascular wall].

The demonstration or exclusion of tumour infiltration into a vessel wall is made possible by IVUS. This was performed 25 times in 23 patients using a 20 MHz probe where there was suspicion of tumour infiltration on the basis of CT, MRI or angiography. IVUS proved very suitable for clarifying the situation, making direct intravascular evaluation of the affected vessel possible. In 10 cases where surgery was performed, the demonstration or exclusion of tumour infiltration into a vein was confirmed operatively in every case. Further experience is necessary before the value of the method for diagnosing early arterial infiltration can be judged.

Adult

Global and regional ventricular function following intracoronary application of papaverine.

Intracoronary injection of papaverine is used to determine coronary flow reserve in patients. The present study was to investigate the effect of papaverine on the performance of myocardium with reduced flow reserve. In nine anaesthetized open-chest dogs a bypass from the aorta to the left circumflex coronary artery (LCX) was established. Left ventricular end-diastolic and aortic pressure, dP/dt, stroke volume, LCX blood flow, and ECG were monitored. The performance of a segment of subendocardial wall supplied by the LCX was assessed by sonomicrometry. Peak reactive hyperaemia after 15s bypass occlusion was 1.44 +/- 0.09 times the baseline flow (41 ml/min), indicating reduced coronary flow reserve. Papaverine was injected into the bypass (0.3, 0.6, 1.2, 2.5, 5.0 mg/ml, 1 ml in 15s). The maximum LCX flow following PAPA 0.3 mg was comparable to peak reactive hyperaemia, but 10-15% higher after injection of 0.6-5.0 mg papaverine. Systolic shortening of the myocardium (control: 17.5% of end-diastolic length) became reduced in a dose-dependent fashion (5-25%) for about 1 min following papaverine injection. Stroke volume (control: 0.94 +/- 0.12 ml/kg) was reduced by about 8%, left ventricular end-diastolic pressure (control: 6.2 +/- 0.8 mmHg) increased by 15%, and dP/dtmin (control: 1850 +/- 150 mmHg/s) was curtailed by 15-25%. The ECG showed a transient T inversion and S-T depression following papaverine administration and in one experiment ventricular fibrillation occurred after the injection of 2.5 mg papaverine. The observed effects of intracoronary papaverine are consistent with the theory of transient subendocardial ischaemia arising from a redistribution of blood flow from the subendocardial to the subepicardial layers, because of greater vasodilatory capacity in the latter than in the former.

Animals

[Comparison of the effect of a selective and a nonselective beta receptor blocker on the ischemic ST segment, lung function and stress-induced decrease in blood glucose].

This study was designed to compare the antihypertensive and anti-ischemic effects of the newly developed cardioselective beta-blocking agent, betaxolol, with the non-selective agent, nadolol, both of which have hydrophilic long acting properties, over a period of 48 hours. Additionally, the study was intended to determine whether betaxolol exerts a lesser influence on pulmonary function and whether beta-1- and beta-2-adrenergic blocking agents also induce a decrease in blood glucose levels during standard bicycle ergometry for three to nine minutes, similar to that reported in association with exercise of longer duration and, if so, whether this effect can be circumvented by the use of a selective agent. Ten patients with angiographically documented CAD, stable exercise angina pectoris and reproducible ST-segment depression of at least 1 mm received on day 1, in a single blind fashion, one tablet of placebo, on day 2 and day 7, in a double-blind, randomized and cross-over fashion, 20 mg betaxolol or 80 mg nadolol, respectively. Bicycle ergometry was performed before, four, 24 and 48 hours after drug with fixed work loads, blood glucose determination before and after ergometry four hours after drug and airway resistance and maximal ventilatory capacity studies were carried out five hours after drug administration. As compared with placebo, betaxolol and nadolol led to reductions of ST-segment depression of 65% (p less than 0.01) and 74% (p less than 0.005) at four hours, of 53% (p less than 0.025) and 56% (p less than 0.01) at 24 hours and 41% (p less than 0.05) and 44% (p less than 0.05) at 48 hours.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic beta-Antagonists