Carotid sinus reflexes during postural changes, naturally elicited fighting behaviour, and phases of sleep in the cat.

Reflex responses of mean blood pressure and of heart rate to either bilateral common carotid occlusion (CO) or unilateral carotid sinus dilatation (CSD) during rest and different behaviours have been compared in conscious cats. Unloading and loading the carotid sinus receptors elicited equal reflex responses both of mean blood pressure and of heart rate during control immobile behaviour (CO: +34 +/- 6 mmHg and +35 +/- 6 beats . min-1; CSD: -37 +/- 4 mmHg and -52 +/- 11 beats . min-1), standing on the hindlimbs (CO: +36 +/- 5 mmHg and +29 +/- 5 5 beats . min-1; CSD: -40 +/- 6 mmHg and -61 +/- 10 beats . min-1), fighting against an attacking animal (CO: +34 +/- 5 mmHg and +31 +/- 5 beats . min-1; CSD: -37 +/- 5 mmHg and -56 +/- 10 beats . min-1), quiet wakefulness (CO: +37 +/- 5 mmHg and +38 +/- 4 beats . min-1; CSD: -34 +/- 4 mmHg and -53 +/- 8 beats . min-1) and synchronised sleep (CO: +36 +/- 5 mmHg and +37 +/- 4 beats . min-1; CSD: -36 +/- 4 mmHg and -52 +/- 6 beats . min-1). Desynchronised sleep was associated with an identical response to CSD (-30 +/- 4 mmHg and -51 +/- 7 beats . min-1) but with a reduced (p less than 0.01) reflex response to CO (+18 +/- 3 mmHg These data indicate that carotid sinus baroreflexes largely maintain their ability to modulate pressure upwards and downwards when blood pressure has been reset at somewhat higher levels by standing and fighting and at somewhat lower levels by synchronised sleep. The selective depression of carotid occlusion responses during desynchronised sleep suggests a central or peripheral shift of the baroreflex stimulus-response curve or a selective central inhibition of the reflex response to baroreceptor unloading.

[Evaluation of the cholesterol-lowering effectiveness of pantethine in women in perimenopausal age]. / Valutazione dell'efficacia ipocolesterolemizzante di pantetina in donne in età perimenopausale.

Cardiovascular diseases are the main cause of death also in women. Their incidence, rapidly growing in the peri-menopausal period, is related to serum levels of total cholesterol and its LDL fraction. It was also shown that the peroxidation of LDL is an additional factor in the genesis of atherosclerotic vascular disease. As long-term treatments with synthetic lipid-lowering drugs may cause undesirable side effects, while pantethine is known to be well tolerated, we treated 24 hypercholesterolemic women (total serum cholesterol greater than or equal to 240 mg/dl), in perimenopausal age (range: 45-55 years, mean +/- SD = 51.6 +/- 2.4) with 900 mg/day of pantethine. This is a precursor of coenzyme A, with an antiperoxidation effect in vivo, and our aim was to confirm its lipid lowering activity in this particular type of patients. After 16 weeks of treatment, significant reductions of total cholesterol, LDL-cholesterol and LDL-C/HDL-C ratio could be observed. No remarkable changes of the main laboratory parameters (fasting blood sugar, B.U.N., creatinine, uric acid) were seen. Efficacy percentages of the treatment were about 80%. None of the patients complained of adverse reactions due to the treatment with pantethine. In conclusion, we suggest that pantethine should be considered in the long-term treatment of lipid derangements occurring in the perimenopausal age.

[Arterial hypertension in perimenopausal women; tolerability of etozolin]. / Ipertensione arteriosa in donne in età perimenopausale; indagine di tollerabilità dell'etozolina.

Twenty women aged 45-55 years with mild-moderate hypertension were treated for 12 months with etozolin, a new loop diuretic. All patients concluded the study; resting systolic pressure was reduced from 164 +/- 3 to 145 +/- 3 mmHg; diastolic blood pressure dropped from 103 +/- 2 mmHg to 90 +/- 1 mmHg. No changes of blood glucose, blood nitrogen, serum Na+, K+, creatinine, cholesterol, triglycerides were observed, nor serious adverse reaction appeared. In conclusion, etozolin is a safe and effective antihypertensive agent in a selection of hypertensive patients highly sensitive to pharmacological side effects.

Direct arterial pressure, heart rate, and electrocardiogram during cigarette smoking in unrestricted patients.

Direct arterial pressure, heart rate, and ECG have been recorded over a 24-hour period in nine individuals who were completely unrestricted throughout the study. Forty-nine separate cigarette smoking episodes were clearly indicated and analyzed. The results of our study confirm a significant increase in arterial pressure five minutes after smoking a cigarette. The systolic rise in pressure (mean 10.7 mm. Hg, P less than 0.001) was approximately twice that of the diastolic rise (5.3 mm. Hg, P less than 0.001) and was present under different conditions of everyday life with notable exception of lying in bed before sleep, We found no quantitative difference between normotensive and hypertensive subjects. There was no certain change in heart rate (mean increase +0.8 beats per minute, t equals 0.59, NS) in the group as a whole. Smoking also had a short-term action consisting of a brief fall in arterial pressure and heart rate occuring over eight to ten heart beats following immediately after the first inhalation of tobacco smoke, followed by a rebound rise in arterial pressure to a level greater than the presmoking level; this is probably a vagal effect. Cigarette smoking caused angina pectoris in one individual and the records showed ST-segment depression in the ECG before the subjective appreciation of pain.

Reversible alteration of myocardial function in gestational diabetes.

Left ventricular function was evaluated in 24 women who developed impaired glucose tolerance only during their pregnancy, i.e. patients with gestational diabetes. The results were compared with those of 25 normal pregnant women and with those of 17 pregnant women with clinical diabetes. The method of systolic time intervals was applied. At the third trimester of pregnancy, both the women with overt diabetes and those with gestational diabetes, when compared with normal pregnant subjects, had a more prolonged pre-ejection period (PEP) and a shorter left ventricular ejection time (LVET) and, consequently, a higher PEP/LVET ratio. Five weeks after delivery, abnormalities of systolic time intervals persisted in patients with clinical diabetes, but there were no differences at this time between patients with gestational diabetes and those in the control group. It is concluded that when a cardiac load is superimposed on patients who develop diabetes only under conditions of stress, as in pregnancy (gestational diabetes), abnormalities of myocardial function appear, which revert to normal when the stressful event is removed.

[Cardiac valvular disease and pregnancy. Haemodynamic aspects and importance of decubitus]. / Cardiopatie valvolari e gravidanza. Aspetti emodinamici ed importanza del decubito.

During the 3rd trimester of pregnancy, 26 women with aortic or mitral valve disease (II class NYHA) have undergone bedside right heart catheterization. Total pulmonary resistances (RPT) have been studied in supine (DS) and lateral (DL) decubitus. The results are compared with those of 7 normal women. It is known that the change from the supine to the lateral posture increases venous return (and cardiac output) by removing the compression which the pregnant uterus causes to the inferior vena cava. This is achieved without increasing the mean pulmonary pressure (PPM) and total pulmonary resistances (RPT); women with mitral and aortic stenosis have little or no increase of cardiac output but always a marked increase of PPM and RPT; the response in patients with aortic and mitral incompetence is closer to normal; an intermediate response was observed in patients with a mitral stenosis and insufficiency. The valvular heart diseases with stenosis badly tolerate the increased cardiovascular burden of pregnancy and are unable to accommodate the increased venous return induced by postural changes, which induces marked elevation of pulmonary pressure and resistances.

Alterations of systolic time intervals in the assessment of myocardial function during hypertensive pregnancy.

The alterations in the systolic time intervals caused by hypertension during pregnancy have been investigated. A group of 20 women who developed hypertension only during pregnancy (HP), and a group of 16 women who began pregnancy with established hypertension (EHP) were matched with 25 normal pregnant women (N). the study was performed (1) during the third trimester, (2) five days after delivery and (3) five weeks after delivery, both in supine and in lateral postures. In the third trimester the two hypertensive groups, when compared with the normal group, were characterized by a shorter left ventricular ejection time (LVETi: 407 +/- 3 ms for the normal group v. 390 +/- 2 ms for the HPO group, P less than 0.001; v. 398 +/- 2 ms for the EHP group, P less than 0.02), and a longer pre-ejection period (PEPi: 138 +/- 2 ms for the normal group v. 154 +/- 2 ms for the HP group P less than 0.001; v. 145 +/- 1 ms for the EHP group, P less than 0.05). When the two hypertensive groups were compared with each other the HP group showed a shortened LVET and a prolonged PEP (P less than 0.01), and also a slower heart rate (HP 74 +/- 3 b min-1. EHP 83 +/- 3 b min-1 P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

[Systolic times adjustment during pregnancy and puerperium (author's transl)]. / Modificazione dei tempi sistolici durante la gravidanza e il puerperio.

During pregnancy and the post partum period important cardiovascular adjustments take place, which for ethical views need a non invasive approach. In the present work we studied the alterations of the Systolic Time Intervals in both supine and lateral decubitus during each trimester and at the fifth day and fifth week after delivery. In the first part of pregnancy a significant reduction of the preejection time (PE) and PE/EVS with an increase of the left ventricular ejection time (EVS) become evident. In the second part the picture reverses to a significantly reduced EVS and increased PE and PE/EVS. This picture even if decreasing, is present in the post partum period. The first part of pregnancy is characterized by a hyperkinetic condition; in the second one the position of the woman becomes important, and the reduction of the EVS is at least partially due to an impaired venous return (compression of the vena cava by the gravid uterus). The persistence of altered systolic time intervals in the post partum (increased PE/EVS) suggest an impaired myocardial performance.

Haemodynamic effects of isometric handgrip exercise in patients convalescent from myocardial infarction.

1. Cardiac performance in response to 30% maximal isometric handgrip exercise was studied in fourteen patients convalescing uneventfully from a first myocardial infarction. In each patient, heart rate, mean arterial blood pressure and cardiac index were measured, and total peripheral resistance was calculated. The covariance of changes in the mean arterial blood pressure and cardiac index in these patients was matched against tolerance limits calculated from published data for normal subjects. 2. All patients had normal haemodynamic values at rest, and showed the usual rise of heart rate and mean arterial pressure during handgrip exercise. However, in six patients (group 1) the rise in mean arterial pressure was, as in normal subjects, accounted for mainly by a rise in cardiac index, with no consistent change in peripheral resistance. In eight patients (group 2), the mean arterial pressure rose to the same level as in group 1, but with a consistent increase in peripheral resistance and a smaller rise in the cardiac index. 3. It is suggested that in a substantial proportion of patients who are making a seemingly uncomplicated recovery from myocardial infarction, it may be possible to unmask an impairment of left ventricular function by means of isometric handgrip exercise.