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Study Objectives: To characterize carotid intima-media thickness (IMT) and plaque occurrence in patients with newly diagnosed obstructive sleep apnea (OSA) without known cardiovascular disease., Design: Prospective study., Setting: Sleep Laboratory and Department of Cardiology of Grenoble University Hospital., Patients and Intervention: OSA syndrome is associated with an increased cardiovascular risk. Carotid IMT is recognized as a marker of preclinic atheroma. A small number of studies have analyzed large-artery wall modifications in OSA syndrome. Eighty-three patients (74 men; mean age +/- SD, 48 +/- 11 years; mean body mass index, 27.4 +/- 4.2 kg/m(2)) were included. Mean respiratory disturbance index was 40.7 +/- 19.2/h, mean nocturnal arterial oxygen saturation (Sao(2)) was 93.1 +/- 2.0%, and mean percentage of recording time spent at Sao(2) < 90% was 8.6 +/- 16.8%. Clinical BP was measured following European Society of Hypertension/European Society of Cardiology recommendations, and 24-h ambulatory BP monitoring was assessed. Ultrasonography was used to determine the carotid IMT and atheromatous plaque occurrence., Measurements and Results: Twenty-five of 83 patients (30%) had carotid wall hypertrophy (IMT > 0.8 mm). In a logistic regression model, mean nocturnal Sao(2) < 92% (odds ratio [OR], 3.9; 95% confidence interval [CI], 1.1 to 12.7) was associated with carotid wall hypertrophy. ORs were even higher after adjustment for BP status (OR, 10.6; 95% CI, 1.6 to 50.9 in normotensive patients) and glucose levels (OR, 4.5; 95% CI, 1.0 to 20.9). Mean nocturnal Sao(2) < 92% and minimal nocturnal Sao(2) < 80% (ORs, 3.1 and 3.1; 95% CIs, 1.0 to 9.4 and 1.0 to 8.5, respectively) were associated with the presence of carotid plaque formation independently of the BP status (hypertensive or normotensive)., Conclusions: The severity of oxygen desaturation appears to be one of the best predictors for carotid IMT and plaque occurrence in OSA patients without known cardiovascular disease. Thus, carotid IMT and plaque formation appeared as early cardiovascular consequences in OSA patients.

Purpose: This article is an update of past and current data on the relationship between obstructive sleep apnea syndrome and cardiovascular diseases., Current Knowledge and Key Points: Obstructive sleep apnea syndrome is a common, but under-recognised, condition and should not be considered simplistically as the association of snoring and obesity. It may be suspected by the clinical history but a definite diagnosis requires the practice of polysomnography. Numerous studies have found a significant relationship between the presence of obstructive sleep apnea syndrome and the occurrence of cardiovascular events. Nonetheless, a definite causal relationship has only been established for the occurrence of hypertension. There are multiple immediate and delayed cardiovascular responses to the apneic events and thus there are many possible physiopathological mechanisms to explain the association of obstructive sleep apnea and cardiac and vascular events, the primary one being sympathetic hyperactivity. The prognosis of obstructive sleep apnea syndrome is closely related to the incidence of cardiovascular events. FUTURE PROSPECTS AND PROJECS: The existence of an independent relationship between obstructive sleep apnea syndrome and atherosclerosis is not yet demonstrated. The beneficial effects of continuous positive airway pressure, the treatment of choice for this condition, on the incidence of cardiovascular diseases remains to be confirmed although recent studies suggest that correct treatment of obstructive sleep apnea syndrome by continuous positive airway pressure may reduce the cardiovascular risk and in particular that of hypertension.

Background: Dobutamine (a beta-receptor agonist), enoximone (a type III selective phosphodiesterase inhibitor), and epinephrine (an alpha- and beta-mimetic) frequently are used in the perioperative management of patients undergoing coronary artery bypass grafting., Methods: We performed a double-blind clinical study to compare the effects on internal mammary artery free flow of low doses of these three positive inotropic drugs. Thirty patients in whom the left internal mammary artery was used for coronary artery bypass grafting were randomized into three groups. Internal mammary artery free flow and hemodynamic measurements were evaluated before and 10 minutes after the intravenous infusion of dobutamine (3 microg x kg(-1) x min(-1)), enoximone (200 microg/kg), or epinephrine (0.05 microg x kg(-1) x min(-1))., Results: A significant increase in free flow occurred only in the dobutamine group (33 +/- 7.5 and 42.2 +/- 7.9 mL/min before and after drug infusion, respectively; p = 0.013). Comparison of the increase in flow between the groups, however, showed no difference. These drugs, at doses designed to produce a positive inotropic effect, caused little increase in the free flow of the internal mammary artery., Conclusions: The use of dobutamine, enoximone, and epinephrine as low-dose positive inotropic treatments in the perioperative and postoperative periods of coronary artery bypass grafting should depend on their positive inotropic effects rather than their vasodilative effects on the arterial grafts.

The objective of the MACH1 study (MEMS for the Assessment of Compliance of Hypertensives) was to evaluate the real behaviour of patients in relation to antihypertensive treatment administered as a single daily dose. After a 2-week period during which no other antihypertensive was allowed to be administered, 590 patients with mild-to-moderate hypertension received 2 mg of trandolapril as a single daily dose in the morning between 7:00 a.m. and 9:00 a.m. for 4 weeks. Treatment was packaged in electronic pillboxes recording the date and time of each opening. Various profiles were distinguished on the basis of the individual chronograms for the 501 patients able to be analysed in terms of compliance, and as a function of the deviations observed in relation to the treatment regimen prescribed. One hundred and two patients (20%) omitted more than 20% of the prescribed doses, either consecutive doses or scattered throughout the month of treatment; these patients were referred to as "omitters". The other patients were classified according to the scatter of openings in relation to the mean time of the dose: 10 "metronome" patients (2%), 126 "regular" patients (25%), 221 "irregular" patients (44%) and 42 "anarchic" patients (8%). Irregularities of dose times were more frequent on public holidays than on week days and in patients living in Paris or the Paris region. "Metronome" patients were older than the overall patient population. The use of an electronic pillbox could allow the attending physician to more adequately adapt his therapeutic approach and management of specific problems of compliance observed in hypertensive patients.

Clinical and 24-hour ambulatory measurements were made in 46 patients with mild to moderate essential hypertension in order to confirm that the efficacy and safety of sustained-release diltiazem LP 300 mg were the same regardless of the time of day at which it was taken. After two weeks of placebo, patients were randomly assigned double-blind to take diltiazem LP 300 mg either morning or evening for four weeks. Diltiazem LP 300 mg significantly lowered diastolic and systolic blood pressure in both groups by clinical or 24-hour ambulatory measurement, and without any difference according to whether diltiazem LP 300 mg was administered morning or evening. A lesser fall in blood pressure during the night in both groups led to study of the effect of diltiazem LP 300 mg according to initial ambulatory diastolic blood pressure level. Diltiazem brought about a greater fall in blood pressure when patients had an ambulatory diastolic pressure of 90 mmHg or more. Clinical, laboratory and electrocardiographic parameters were all satisfactory, regardless of the time at which the drug was taken.

Blood pressure (BP) is not a constant parameter, but exhibits variations, which involve a change in its value with time, and variability, which corresponds to the extent of this variation. A circadian pattern of BP, with higher values during the day than at night, is one expression of this variation in BP. This variation corresponding to the circadian pattern is dependent on both physical constraints and psychosensory factors. Investigation of variability implies consideration of both long-term and shorter term changes in BP. Long-term variability can be assessed by ambulatory determinations of BP, which can be carried out at intervals of 1/4 hour. This variability can be used to define the daytime/nighttime alteration of the circadian cycle, with the possible absence of the nocturnal reduction in BP or even a reversal of this circadian pattern. An abnormality of this type would be of prognostic importance, particularly in terms of impact on the left ventricle. Medium- or above all short-term variability can be assessed only from the change in beat/beat difference in BP and heart rate (HR) which depends on vagal tone and the orthosympathetic system. This variability can be detected by invasive methods and, more recently, using non-invasive methods (Finapres). It would seem that changes in this variability may reveal a defect in baroreceptor control which it is useful to identify for both diagnostic and therapeutic purposes.

Three french specialist centers have included 19 hypertensive patients in an open cooperative study of the effect of labetalol (L = 200 to 400 mg b.i.d.) on the 24 hour blood pressure (24 h - B.P.) recording by a non invasive method (Spacelabs - Squibb Medical Systems), with a particular assessment of the early morning rise of BP. Each patient was subjected to 2 assessments at the end of a 14 days' placebo period and of a 28 days' treatment period. At the end of the study, the systolic (SBP) and diastolic (DBP). B.P. were significantly decreased at rest (p less than 0.001) and on the 24 hours recording (p less than 0.001). The reduction of B.P. was also significant on day period from 7 a.m. to 22 p.m. (p less than 0.001) and night period from 22 a.m. to 7 a.m. (p less than 0.05) as well as on the early morning period, 3 hours before and after waking (p less than 0.001). The heart rate was significantly reduced during the day (p less than 0.05) and was not on the night. The slope of the early morning rise of B.P. was marked after placebo and significantly decreased after labetalol with a reduction of 52% for SBP and 49% for DBP (p less than 0.001). These results show that labetalol has an antihypertensive effect over 24 hours with a marked effect on the early morning rise of B.P.

Stress tests have been performed for a long time in patients with coronary disease. The study of blood pressure variations, under these circumstances, is also interesting in hypertension. Several types of stress tests, dynamic and static, may be performed. Dynamic tests on ergometric bicycles are the most frequently performed. The evolution of the BP during stress increases regularly and there is a linear correlation between the BP values and the level of work as well as the heart rate (HR). It is therefore possible to individualize a reference blood pressure profile, according to age and sex. The stress may find applications from a diagnostic, prognostic and therapeutic standpoint. First of all, in borderline HT, the stress test enables to confirm the HT and better differentiate between hyperemotional and hyperkinetic patients. In severe hypertension, the stress test permits to better define the magnitude of the haemodynamic disorder. In true hypertensive patients, undergoing major physical stress (work, sports...) the stress test permits to evaluate the tolerance to stress and the faculties of myocardial adaptation. From a prognostic standpoint, the incidence of permanent hypertension is 2 to 3 times higher in patients presenting an abnormal blood pressure profile. There is a significant correlation between the BP at maximum stress and the left ventricular mass index at all stages of the HT. The stress test makes it possible to better define the mode of action of antihypertensive medications, prescribe a personalized treatment according to these patients reactivity to stress and guarantee the correction of blood pressure abnormalities, since normalisation at rest does not necessarily imply a normalisation during stress.