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J Cosyns

Publications and source records attributed to J Cosyns.

31 records · Page 2Linked to original sources
PubMed1976

Superiority of developed over total pressure for heart contractility indices in dogs.

The independence of indices of contractility to Starling effects was tested in 6 closed-chest dogs. After vagal and beta-receptors blockade, indices calculated with total left ventricular isometric pressure (TP), were shown to be strongly dependent of rises in end-diastolic pressure (LVEDP) induced by dextran infusion. At LVEDP of 14.6 +/- 1.5, 22.2 +/- 1.1 and 32.8 +/- 1.5 mm Hg (+/- SEM), the peak value of velocity of the contractile elements calculated with total pressure (peak VCE, TP) diminished by 21, 40 and 50%, and the extrapolated value of VCE, TP at zero total pressure (Vmax, TP) diminished by 15, 30 and 44%. In contrast, indices calculated with developed pressure (DP = TP-LVEDP) at the same LVEDP were much less influenced, particularly the extrapolated value of VCE, DP at zero DP (V max, DP5) and (peak dP/dt)/DP did not significantly change. During angiotensin infusion, expected decreases in TP indices secondary to LVEDP rises were partially masked by simultaneous increases in contractility, and DP indices tended to rise. On the other hand, with minimal changes in LVEDP, as during calcium injection and paired stimulation, increases in TP and DP indices demonstrate inotropic effects equally well. Our study also shows that, besides Vmax calculated with DP, the instantaneous ratio of peak dP/dt and DP can also be proposed as a simpler and thus more convenient index of contractility independent of volume changes.

Angiotensin II↗
PubMed1975

Maximal exercise testing in patients with spontaneous angina pectoris associated with transiet ST segment elevation. Risks and electrocardiographic findings.

Six patients with spontaneous angina associated with transient ST segment elevation had a multistate maximal exercise (bicycle) test. In 5 patients, typical electrocardiographic changes were recorded during exercise, namely ST segment elevation often accompanied by an increase in the voltage of the R wave and a widening of the QRS complex. Four of these patients developed severe rhythm disturbances: ventricular tachycardia (2 cases) and ventricular flutter (1 case) were the reason for early interruption of the test in 3 patients, while 1 patient had a short run of ventricular tachycardia after exercise. These rhythm disturbances which spontaneously regressed in all cases were consistently preceded by obvious ST elevation and in 2 patients were attended by slight chest discomfort. Maximal exercise testing of patients suspected of variant angina provides important diagnostic information in many patients, but the risks of potentially lethal arrhythmias should be considered and resuscitation facilities should always be immediately available.

Adult↗
PubMedDate not supplied

Idiopathic hypertrophic subaortic stenosis: long-term surgical results.

The results of surgery in 21 patients with I.H.S.S. are reported. Dyspnea, angina pectoris and syncope were the most common symptoms in decreasing frequency. Before the operation, 5 patients were in New York Heart Association's functional class II, 10 in class III and 6 in class IV. The mean resting peak systolic pressure gradient was 66 mm Hg in 20 patients and mean left ventricular end-diastolic pressure was 14 mm Hg in 19 patients. The ventriculoseptomyectomy accomplished through a transaortic approach is the procedure of choice. The operative mortality rate was 14% (3 of 21 patients). There were 2 late deaths from congestive heart failure. Any sudden death did not occur. The remaining 16 patients have been followed up for a mean of 75 months (range 12 months to 11 years), 11 patients are in functional class I, 4 in class II and 1 in class III. Complete left-bundle-branch block occurred in 3 patients. Our study with a long post-operative follow-up period, documents that surgery results in good to excellent alleviation of symptoms in survivors. The elevated pre-operative left ventricular end-diastolic pressure has a significantly poor prognosis. We currently recommend surgery for the symptomatic patients who have not responded to medical therapy, not late in the symptomatic course of the disease.

Adolescent↗