[Cardiac rehabilitation, a proven intervention underutilized in the French-speaking part of Switzerland]. / Réadaptation cardiovasculaire, un- bien sous-utilisé.

Cardiac rehabilitation is associated with a reduced risk of recurrence and mortality after an acute coronary syndrome. Cardiac rehabilitation is a multidisciplinary approach which starts during the acute hospital phase, then followed by a four to six weeks home-based or stationary program, in order to maintain long-term lifestyle changes. Despite the important health benefits of cardiac rehabilitation and its cost-effectiveness, only half of the patients in Europe will achieve a cardiovascular prevention program after an acute coronary syndrome. In the French part of Switzerland, one explanation for this low adherence might be the lack of both stationary and home-based program facilities.

Percutaneous closure of atrial septal defect type ostium secundum using the new Intrasept occluder: initial experience.

We report the first experience obtained with the new Intrasept device. We attempted to treat 35 patients with a mean age of 43 +/- 21 years. The mean size of the defect was 17/15 mm. It was successfully closed in 31 patients. In the remaining four the device could not be stabilized because of excessive defect size. A small residual shunt was present immediately following implantation in three patients. No complications occurred during the procedure and at 6 months, 31 patients had an uneventful outcome. Only one patient had a small residual shunt. No thrombus, embolization, or device fracture was documented during a mean follow-up of 17 +/- 11 months. Percutaneous closure of ASD ostium secundum is feasible with the Intrasept device with a high success rate and very good medium-term outcome. Our initial experience and results were excellent with small to medium size defects, however, large defects (>20 mm) remain challenging.

[Percutaneous closure of patent foramen ovale: preliminary experience with the PFO Star]. / Fermeture percutanée de foramen ovale perméable: expérience préliminaire avec le PFO Star.

This article reports the experience of percutaneous closure of patent foramen ovale with the PFO Star device. Between January 2000 and December 2002, 44 consecutive patients with a mean age of 53 years were included in this registry. The implantation of the prosthesis was successful in 43 patients (98%): in 1 patient the atrial septum could not be crossed at operation. An early complication was observed in 3 patients (7%): one had transient amnesia and two patients had temporary ST elevation in the inferior ECG leads. Four patients (7%) had late complications: there was one case of spontaneously regressive atrial fibrillation, two recurrences of stroke (one in the patient without an implanted prosthesis and the other in a patient in whom the patent foramen ovale had been closed). Finally, one patient developed a fistula between the aorta and right atrium which occluded spontaneously when the anticoagulants were stopped. Complete closure of the patent foramen ovale was confirmed at 1 year in 92% of patients. The authors conclude that this preliminary experience shows that closure of patent foramen ovale with this device is effective and safe.

Clopidogrel loading dose regimens: kinetic profile of pharmacodynamic response in healthy subjects.

Clopidogrel, a potent novel platelet ADP-receptor antagonist, induces a significant inhibition of ADP-induced platelet aggregation. Maximum inhibition of 40 to 50% is observed 2 to 5 hours after a single 400 mg dose. The same level of inhibition is achieved with 75 mg once daily at steady state, i.e., after 3 to 7 days of repeated dosing. Based on these data, two studies were undertaken to investigate whether a treatment regimen comprising a large initial dose (loading dose) of clopidogrel, followed by daily doses of 75 mg, might provide a sustained steady-state level of inhibition of platelet aggregation induced by 5 microM of ADP within hours after first dosing. In one study, 10 healthy male subjects received a 375 mg loading dose of clopidogrel on day 1, then daily doses of 75 mg from day 2 to day 10. Mean inhibition of platelet aggregation, already significant at 30 minutes, reached 55+/-8.2% (+/-SEM) at 60 minutes, and a maximum of 80+/-3.6% at 5 hours. No further significant change was observed between 5 hours and 24 hours, and from day 2 through day 10 with subsequent daily doses of 75 mg. In the second study, conducted according to a randomized, single-blind design, four parallel treatment groups of nine healthy male subjects received a loading dose of 75 mg, 150 mg, 225 mg, or 300 mg of clopidogrel on day 1, respectively, and 75 mg once daily from day 2 to day 5. Mean (+/-SD) inhibition of platelet aggregation over the 2 to 24 hours post-loading dose period was 22+/-14.5%, 21+/-13.4%, 35+/-20.6% and 31+/-13.3%, respectively. On day 5, it was 48+/-14.7%, 33 +/-14.1%, 51+/-15.7% and 40+/-10.9% for the 75, 150, 225 and 300 mg loading dose groups, respectively. The smallest day 1 to day 5 difference was observed for the 300 mg group and the largest for the 75 mg group, indicating that the development of the full inhibitory effect of clopidogrel was faster with the loading doses higher than with 75 mg, and fastest with the 300 mg loading dose. These data and those of previous studies indicate that a dose of 300 to 400 mg produces a rapid onset of the pharmacodynamic action of clopidogrel, with levels of inhibition close to steady-state reached within 2 hours.

[Bicycle exercise echocardiography in the supine position: a simple and effective study method for the detection and localization of myocardial ischemia by the first consulted cardiologist]. / Echocardiographie à l'effort sur cyclo-ergomètre en position couchée: une méthode d'investigation simple et efficace, à la portée du cardiologue de premier recours pour la détection et la localisation de l'ischémie du myocarde.

Exercise echocardiography is increasingly used as an investigative technique, now that dynamic images can be captured digitally. Its equivalent reliability compared to scintigraphic methods has been demonstrated in a hospital setting. This study is an attempt to analyse its impact in daily practise. Standardized progressive stress was provided by bicycle ergometry in a supine position. Echocardiographic images of complete cardiac cycles were obtained in standard apical and parasternal short axial views before, during and after maximum effort and digitized for simultaneous analysis of synchronized images at rest and during exercise. 279 patients were studied (231 men, 48 women, mean age 61 +/- 10 years). Image quality was suboptimal in four cases. In the remaining 275 cases, ischemia was detected in 125 cases, the test was negative in 141 cases and doubtful in nine cases. Control by selective coronary angiography, as motivated by the clinical situation, was performed in 72 cases. In this particular group, exercise echocardiography showed 89% sensitivity, which is significantly higher than the figure of 63% recorded for conventional exercise testing (p < 0.0001). Exercise echocardiography by bicycle ergometer in a supine position is a valid, noninvasive investigative technique which can be used in an outpatient situation (feasibility 95%), since it is available on the spot. Its value appears greatest in cases where exercise ECG was not conclusive. A negative result enables the first consulted cardiologist to reassure the patient immediately, the favourable prognostic value of such a result having been demonstrated in the literature.

Inhaled nitric oxide for high-altitude pulmonary edema.

BACKGROUND: Pulmonary hypertension is a hallmark of high-altitude pulmonary edema and may contribute to its pathogenesis. When administered by inhalation, nitric oxide, an endothelium-derived relaxing factor, attenuates the pulmonary vasoconstriction produced by short-term hypoxia. METHODS: We studied the effects of inhaled nitric oxide on pulmonary-artery pressure and arterial oxygenation in 18 mountaineers prone to high-altitude pulmonary edema and 18 mountaineers resistant to this condition in a high altitude laboratory (altitude, 4559 m). We also obtained lung-perfusion scans before and during nitric oxide inhalation to gain further insight into the mechanism of action of nitric oxide. RESULTS: In the high-altitude laboratory, subjects prone to high-altitude pulmonary edema had more pronounced pulmonary hypertension and hypoxemia than subjects resistant to high-altitude pulmonary edema. Arterial oxygen saturation was inversely related to the severity of pulmonary hypertension (r=-0.50, P=0.002). In subjects prone to high-altitude pulmonary edema, the inhalation of nitric oxide (40 ppm for 15 minutes) produced a decrease in mean (+/-SD) systolic pulmonary-artery pressure that was three times larger than the decrease in subjects resistant to such edema (25.9+/-8.9 vs. 8.7+/-4.8 mm Hg, P<0.001). Inhaled nitric oxide improved arterial oxygenation in the 10 subjects who had radiographic evidence of pulmonary edema (arterial oxygen saturation increased from 67+/-10 to 73+/-12 percent, P=0.047), whereas it worsened oxygenation in subjects resistant to high-altitude pulmonary edema. The nitric oxide-induced improvement in arterial oxygenation in subjects with high-altitude pulmonary edema was accompanied by a shift in blood flow in the lung away from edematous segments and toward nonedematous segments. CONCLUSIONS: The inhalation of nitric oxide improves arterial oxygenation in high-altitude pulmonary edema, and this beneficial effect may be related to its favorable action on the distribution of blood flow in the lungs. A defect in nitric nitric oxide synthesis may contribute to high-altitude pulmonary edema.