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Objectives: We investigated whether maintenance therapy with clopidogrel 150 mg/day produces greater platelet inhibition than the standard 75-mg/day dose and whether the higher maintenance dose increases platelet inhibition in low responders to clopidogrel 75 mg/day., Background: Patients show interindividual variability in their platelet response to clopidogrel. Low responders could potentially obtain greater clinical benefit from greater doses of clopidogrel., Methods: One hundred fifty-three elective percutaneous coronary intervention patients were randomized to clopidogrel 150 mg/day (n = 58) or 75 mg/day (n = 95) for 4 weeks, with vasodilator-stimulated phosphoprotein assay-guided switching to clopidogrel 150 mg/day after 2 weeks in low responders (platelet reactivity index >or=69%). All patients received aspirin 75 mg/day., Results: After 2 weeks, clopidogrel 150 mg/day produced a significantly lower platelet reactivity index than clopidogrel 75 mg/day (43.9 +/- 17.3% vs. 58.6 +/- 17.7%; p < 0.0001). The proportion of low responders was significantly lower in patients randomized to clopidogrel 150 mg/day than in those randomized to clopidogrel 75 mg/day (8.6% vs. 33.7%; p = 0.0004). In the clopidogrel 75 mg/day group, 64.5% (20 of 31) of low responders became responders after switching to clopidogrel 150 mg/day for 2 weeks. No major bleeds occurred during the study; the incidence of minor bleeds was similar in each treatment group., Conclusions: In elective percutaneous coronary intervention patients, a 150-mg/day clopidogrel maintenance dose produces greater inhibition of platelet function than clopidogrel 75 mg/day. In low responders to clopidogrel 75 mg/day, switching to clopidogrel 150 mg/day overcomes low responsiveness in a majority of patients. These findings warrant further clinical evaluation. (VASP-02; EudraCT number: 2004-005230-40).

Spontaneous idiopathic pneumopericardium (SIPP) in young subjects is a rare disorder since, apart from the case described here, only 28 cases have been reported in the literature. It occurs mainly in young adults. The physiopathology of the disorder involves alveolar rupture, as described by Macklin. The symptoms of SIPP are dominated by chest pain, which usually develops suddenly and is combined with dyspnea. Clinical examination is not very helpful, cardiac auscultation detects either pericardial rubbing or a more suggestive metallic sound. Recovery usually occurs without treatment, but there is a risk of long-term recurrence. An unusual complication to be feared is aerial tamponade, which may be life-threatening and calls for emergency draining. The treatment of SIPP involves strict bed-rest, symptomatic treatment of the pain and clinical monitoring.

Pneumopericardium is defined as the presence of air in the pericardial cavity. It is a rare condition in adults, usually due to trauma; it is commoner in the more exposed neonate and usually iatrogenic. The clinical presentation of chest pain and shortness of breath is associated with the pathognomonic auscultatory sign described by Bricheteau: a water-mill bruit. The diagnosis is confirmed by chest X-ray which shows the air-gap sign surrounding the cardiac silhouette. The principal differential diagnosis is a pneumomediastinum. The prognosis of pneumopericardium depends on the cause and complications of which tamponade and infection are the most serious and potentially life-threatening. The treatment of pneumopericardium is bed rest and surveillance when uncomplicated: evacuation of the air becomes necessary when complications set in.

It is still very difficult to study the mechanisms of action of anti-arrhythmic drugs in human clinical studies. The use of continuous electrocardiographic monitoring offers a number of advantages in this field. In this study, the authors evaluate the mechanisms of action of fenoxedil hydrochloride on atrial fibrillation. Holter monitoring suggests that there is a probable synergy between fenoxedil and the autonomic nervous system.

The introduction of data processing techniques into the interpretation of electrocardiograms and the rapid progress towards automatization require a multiplication of the criteria of decision and an exact evaluation of their performance. The ECG diagnosis of left ventricular hypertrophy depends on a large number of parameters. Only the aVR lead has not been fully exploited to date. This study proposes a corrected measurement of S in aVR, with an amplitude of S aVRc greater than or equal to 11 mm being the parameter with the best performance and the best predictability.

The diagnostic value of thallium 201 (201Tl) myocardial imaging was studied in 57 patients with chronic respiratory diseases, most with COPD (n = 46), by comparing the results to hemodynamic findings. In healthy subjects, the right ventricle (RV) is not visualized; therefore, any recorded activity of the RV was considered as indicating RV hypertrophy due to RV pressure overloading (RVPO). RV activity was graded from 0 (no activity) to 3 (activity greater than or equal to that of the left ventricle). Patients were divided into three groups according to the level of the pulmonary artery mean pressure (PPA): PPA less than or equal to 20 mm Hg (no pulmonary arterial hypertension [PAH] ) = group 1, n = 20; PPA ranging from 21 to 30 mm Hg (mild to moderate PAH) = group 2, n = 20; PPA greater than 30 mm Hg (marked PAH) = group 3, n = 17. RV was visualized in 14 patients in group 3 (82 percent) and in 13 patients in group 2 (65 percent). For all patients with PAH (2 + 3) the sensitivity of 201Tl imaging for the diagnosis of RVPO was of 73 percent, higher than that of ECG and echocardiography (both 51 percent). The sensitivity of 201Tl, even if moderate (65 percent) was better than that of ECG (30 percent) or echo (40 percent) in patients with mild-to-moderate PAH (group 2). A high RV activity (grade 3) was observed in only three patients. The specificity of this method (obtained from results in group 1) was of 80 percent vs 89 percent for echo and 100 percent for ECG. These results suggest that 201Tl myocardial imaging is a rather sensitive method and could be of interest for the noninvasive diagnosis of RVPO in COPD patients.

Right heart catheterisation (reference method) and M-mode echocardiography were performed in 90 patients with chronic respiratory failure (73 BPCO-chronic airflow obstruction and 17 non-BPCO). The aim of this study was to assess the place of echo-cardiography in the diagnosis and assessment of pulmonary arterial hypertension (HTAP) and/or right ventricular hypertrophy (HVD). The results are somewhat deceptive; first as reliable measurements were impossible in 20% of cases (due to airways distension), then because the sensibility of the method is only 75% (only 62.2% in the group with moderate HTAP with a mean pulmonary artery pressure (PAP) between 21 and 30 mmHg, where as the specificity was satisfactory (87.5%). The best coefficient of linear correlation was observed between the PAP and the end-diastolic diameter of the right ventricle (DTDVD) (r = 0.52; p less than 0.001). Such a correlation does not allow for a prediction of an exact level of PAP in individual cases. The combination of 3 non-invasive methods (ECG, Echo-cardiography and myocardial scintigraphy) allows for an excellent overall sensibility (91.7%) but to the detriment of the specificity (66.6% only).

The respective value of four non-invasive methods for the diagnosis of pulmonary arterial hypertension (PAH) was investigated in 63 COPD patients, using right heart catheterization as the reference method: 22 patients had no resting PAH (pulmonary artery mean pressure (PAP) less than or equal to 20 mmHg); 26 patients had mild PAH (PAP = 21-30 mmHg); and 15 patients had moderate to severe PAH (PAP greater than 30 mmHg). The specificity of ECG was 86% and the sensitivity 51% (only 38% in mild PAH). The specificity of radiological measurements was 63% and the sensitivity 46% (38% in mild PAH). Echocardiography (echo) had the best results with a specificity of 75% and a sensitivity of 78% (73% in mild PAH), but reliable echo measurements were available in only 52 out of 63 patients. Myocardial scintigraphy had a specificity of 68% and a sensitivity of 66% (58% in mild PAH). A stepwise regression analysis (including one echo, one ECG, one radiological and one functional variable) explained only 43% of the variance of PAP (multiple r = 0.66). These results suggest that no individual method is sufficiently reliable for predicting the presence of PAH, and particularly mild PAH, but the combination of echo + myocardial scintigraphy allows the prediction of PAH with a good probability. The precise level of PAH cannot be estimated, even when using multiple regression equations.

In a series of 12 patients, the right atrial effective and functional refractory periods (ERP and FRP) were determined at 3 different sites and at 3 different intensities (threshold intensity and double and triple the threshold intensity). The mean of the range of the ERP in the same atrium was 43.4 ms and that of the FRP was 53.5 ms. These ranges appear to be independent of the intensity of stimulation. However, the values of the refractory periods were strictly correlated with the intensity of the stimulation current used. This correlation appeared to be much more marked for the ERP than for the FRP.