Search PubMed⌕ Search

Biomedical subjects

M Condorelli

Publications and source records attributed to M Condorelli.

At least 163 records · Page 9Linked to original sources
PubMed1984

[Closed-chest interruption of abnormal bundles of His. Its use in a case of "incessant" tachycardia guided by an experimental model].

The usefulness and safety of intracardiac discharge of a synchronized DC shock through a catheter-electrode to ablate the His bundle has led the Authors to evaluate the use of this technique to interrupt bypass tracts located near the coronary sinus. Acute experiments were performed in 10 open chest dogs. A tripolar 6F catheter-electrode was placed in the coronary sinus and 2 or 3 unipolar shocks of 80-120 joules were delivered to each electrode. After the procedure the coronary sulcus was inspected and a lesion 2-3 cm wide and 2-4 mm deep with edema and haemorrhage was found in all cases. On the basis of the data obtained in dogs, the technique was successfully used in a woman with "incessant" supraventricular tachycardia due to reentry through a concealed anomalous pathway located in the posterior septum. A careful mapping of the coronary sinus allowed the localization of the earliest retrograde atrial activation. Two shocks of 120 joules were delivered in the coronary sinus at the site suggested by the electrophysiologic mapping. The patient has remained free from tachycardia since the time of the discharge (follow-up: three weeks).

Adult↗
PubMed1983

Prajmalium bitartrate in chronic ventricular arrhythmias: comparison with disopyramide.

24-h ECG recordings were used to assess the efficacy of prajmalium bitartrate (PB) in reducing the incidence and the severity of premature ventricular complexes (PVCs), and to compare its antiarrhythmic action with that of Disopyramide. 13 patients with frequent PVCs were distributed randomly into 2 groups. The first group of 7 patients received PB 80 mg/day for 4 days as their first treatment, and disopyramide 400 mg/day for a further 4 days as the second therapy. The succession of the drugs was reversed in the other group of 6 patients. Analysis of the Holter recordings showed that PB and disopyramide reduced PVC frequency to a similar extent as compared to the corresponding wash-out period, viz. by 56.7% (p less than 0.05) and 62.1% (p less than 0.01), respectively. Thus, PB appears to be an effective antiarrhythmic drug and comparable to disopyramide. It may be used to prevent premature ventricular complexes and runs of ventricular tachycardia.

Adult↗
PubMed1983

Inhibition of histamine release from human basophils in vitro by calmodulin antagonists.

Calmodulin is a ubiquitous and versatile Ca2+-binding protein that plays a pivoting role in cellular metabolism. We have investigated the possibility that calmodulin plays a role in immediate hypersensitivity reactions by evaluating the effects of two agents, trifluoperazine dihydrochloride (TFP) and the sulfonamide derivative N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7) which selectively bind to calmodulin. TFP and W-7 cause a dose-dependent inhibition of histamine secretion from human basophils in vitro induced by several immunological (i.e., antigen and anti-IgE) and nonimmunological (i.e., formyl-methionine-containing peptide and the Ca2+ ionophore A23187) stimuli. These results indicating that two specific calmodulin antagonists are potent inhibitors of the secretory response of human basophils support the hypothesis that calmodulin may play a role in the control of the release of preformed mediators from human inflammatory cells.

Adult↗
PubMed1983

Immunofluorescence localization of calmodulin in human polymorphonuclear leukocytes.

Human polymorphonuclear leukocytes (PMNs) were purified (approximately equal to 99%) from peripheral blood of normal, adult volunteers. The indirect immunofluorescence technique was used to investigate the presence and the localization of calmodulin in human PMNs. The cellular distribution of calmodulin has been evaluated using an affinity chromatography-purified sheep IgG anti-calmodulin and fluorescein-conjugated rabbit anti-sheep IgG. The anti-calmodulin immunofluorescence pattern suggests that calmodulin is evenly distributed throughout the cytoplasm of human PMNs.

Adult↗
PubMed1983

Dilazep-induced reduction of ischemic necrosis in rats with coronary artery occlusion.

To assess whether dilazep reduces myocardial necrosis we assigned 72 rats that survived coronary artery occlusion to 3 groups. The first control group (n = 26) received coronary occlusion and was untreated. The second group (n = 21) received coronary occlusion and was treated with dilazep (150 micrograms/kg s.c.) every 8 hours for 48 hours. The third group (n = 25) was sham-operated. Forty-eight hours later the creatine-kinase activity of the left ventricle was measured. The calculated left ventricular fraction that survived the occlusion was larger in dilazep-treated rats (44.5 +/- 4.1% of left ventricle) than in controls (31.2 +/- 3.2%; P less than 0.05). Twenty-six more rats also underwent coronary occlusion; 12 were controls and the remaining 14 were treated with dilazep at the same time and dose as before and killed 21 days after occlusion. Infarct size was evaluated on histological sections of the hearts by planimetry. The amount of left ventricle preserved from necrosis was larger in dilazep-treated rats, 82.1 +/- 0.9%, compared to controls 69.5 +/- 1.4% (P less than 0.05). Dilazep seems effective in preserving myocardial tissue from ischemic necrosis, and its beneficial effects are long-lasting, producing permanent reduction of infarct size.

Animals↗
PubMed1983

Protective role of collaterals in patients with coronary artery occlusion.

We reviewed the clinical, hemodynamic and angiographic data of 105 patients with right coronary artery occlusion and 82 patients with left anterior descending coronary artery occlusion, subdivided into 3 groups by the presence and quality of collaterals to the occluded coronary (absent, poor or good collaterals). We found that patients with right coronary artery occlusion and good collaterals had a lower frequency of diaphragmatic myocardial infarction (60%) than patients with absent collaterals (100%) (P less than 0.01). In addition, in patients with old diaphragmatic myocardial infarction, both poor and good collaterals were associated with a lower frequency of severe asynergy of the diaphragmatic left ventricular segments at left ventriculography (54% and 14%, respectively), compared to patients with no collaterals to the right coronary artery (92%, P less than 0.02 vs. poor collaterals, P less than 0.001 vs. good collaterals). In contrast, in patients with left anterior descending coronary artery occlusion, the presence of either poor or good collaterals to the left anterior descending coronary artery was not associated with a lower frequency of old anterior myocardial infarction, or, in patients with old anterior myocardial infarction, with a less severe asynergy of the anterior left ventricular segments. Our results suggest that collaterals are effective in protecting the diaphragmatic left ventricular wall in patients with right coronary artery occlusion, but not the anterior left ventricular wall in patients with left anterior descending coronary artery occlusion.

Collateral Circulation↗
PubMed1983

Transesophageal pacing for prognostic evaluation of preexcitation syndrome and assessment of protective therapy.

An esophageal lead was used to perform decremental atrial pacing and elective induction of atrial fibrillation (AF) in 5 patients with the Wolff-Parkinson-White (W-P-W) syndrome before and after amiodarone therapy. In the control state, 1:1 atrioventricular (AV) conduction over the accessory pathway ranged from 220 to 260 ms (mean 232). The shortest R-R interval during AF ranged from 190 to 210 ms (mean 198). The ventricular rate ranged from 175 to 212 beats/min (mean 196). After amiodarone therapy, the shortest cycle length with 1:1 AV conduction increased in all patients, ranging from 290 to 540 ms (mean 370); during AF, no preexcited beat was present in 2 patients, whereas the minimal preexcited R-R interval in the remaining 3 was 290, 240, and 370 ms, respectively. The ventricular response during AF decreased in all patients. Thus, esophageal pacing is a useful method for identifying patients at risk with the W-P-W syndrome and for assessing appropriate management in individual patients. Amiodarone provides protection against life-threatening arrhythmias in these patients.

Adolescent↗
PubMed1983

Predictability of antihypertensive efficacy of selective beta 1 blockers.

The possibility that hemodynamic and biohumoral factors may help predict the antihypertensive effectiveness of selective beta 1 blockers was investigated. The effects of 3 wk of treatment with two selective beta 1 blockers, metoprolol and atenolol, were observed in 54 patients with mild or moderate essential hypertension. No significant difference between the hemodynamic effects of the two drugs was found. The percent fall in systolic blood pressure induced by the two correlated strongly with the pretreatment values of the chronotropic response to isoproterenol and with the pretreatment values of cardiac output, heart rate, and plasma renin activity (PRA). There was no correlation between the decrease in systolic blood pressure induced and initial 24-hr urinary catecholamine output, total peripheral resistance, and plasma aldosterone. Percent fall in diastolic blood pressure correlated only with the pretreatment levels of PRA. Our results support the view that the hypotensive effect of beta 1 blockers are predictable on the basis of the pretreatment values of chronotropic response to isoproterenol, PRA, heart rate, and cardiac output.

Adult↗
PubMed1983

Haemodynamic and clinical effects of long-term treatment of essential hypertension with captopril.

Captopril, an orally active inhibitor of angiotensin converting enzyme, was administered for 12 months to 20 patients with mild or moderate essential hypertension who initially responded favourably to this pharmacological treatment. Captopril induced a significant reduction in blood pressure which remained unmodified throughout the study. This fall in blood pressure was mainly due to a significant decrease in total peripheral vascular resistance, since no change in cardiac output was observed. Simultaneously, there was no significant change in left ventricular anatomy and performance evaluated by echocardiographic technique.

Adult↗
PubMed1983

Increased cardiac output and lowered peripheral resistance during metoprolol treatment.

Echocardiography was performed at every six months in hypertensives well controlled on metoprolol, 100 mg twice a day. After six months' treatment blood pressure was reduced from 177/110 mm Hg to 147/88 (p less than 0.02). LV wall thickness (septum + posterior wall) was unchanged 2.10 cm (2.14), and a significant drop in cardiac output (CO) to 5.0 l/min (6.1, p less than 0.02) was recorded (pretreatment values in brackets). After 24 months' treatment LV wall thickness was reduced to 1.94 cm (p less than 0.02), total peripheral resistance (TPR) to 17.3 mm Hg/l/min (23.4, p less than 0.02) and CO increased to 6.7 l/min (6.1, n.s.). After six months' treatment, there was thus a drop in BP with a significant drop in CO and unchanged TPR. After 24 months' treatment, however, CO was back to the pretreatment level and the drop in BP was entirely caused by a drop in TPR which was probably secondary to a reduction in the wall thickness of the arterial resistance vessels as judged by the relationship between the reduction in wall thickness in the LV and the reduction in TPR during the treatment.

Adult↗