Kinetics of oxygen consumption during and after exercise in patients with dilated cardiomyopathy. New markers of exercise intolerance with clinical implications.

OBJECTIVES: This study analyzed the kinetics of oxygen consumption during and after a maximal cardiopulmonary exercise test in patients with dilated cardiomyopathy. The prognostic information derived from indexes of recovery was also studied. BACKGROUND: Previous studies have examined the kinetics of oxygen consumption during a short recovery period in a limited number of patients. To our knowledge, no study has examined the prognostic information derived from indexes of recovery. METHODS: We studied 153 patients and 55 control subjects. We calculated the ratio between total oxygen consumption during exercise and recovery, the half-recovery time of peak oxygen consumption, the time constant of recovery, the recovery time and the ratio between duration of exercise and recovery time. RESULTS: Recovery of oxygen consumption was significantly delayed in patients, and this delay was related to the degree of exercise intolerance. After a median follow-up period of 439 days, for the total study group, percent of predicted peak oxygen consumption (p = 0.003) and ejection fraction (p = 0.03) were independent predictors of survival. In a subgroup of patients with moderate exercise intolerance (percent peak oxygen consumption > 40%), the ratio between total oxygen consumption during exercise and recovery (p = 0.013) and the ejection fraction (p = 0.013) were independent predictors of survival. CONCLUSIONS: The kinetics of oxygen consumption during recovery was delayed in patients with dilated cardiomyopathy. Although indexes of recovery were not prognostic markers in the total study group, the ratio between total oxygen consumption during exercise and recovery was an independent prognostic marker in patients with moderate exercise intolerance.

Right ventricular ejection fraction is an independent predictor of survival in patients with moderate heart failure.

OBJECTIVES: We sought to study the relationship between survival and right ventricular ejection fraction (RVEF) in a subgroup of patients with moderate congestive heart failure (CHF). BACKGROUND: It has been demonstrated that RVEF is an independent predictor of survival in patients with advanced CHF. METHODS: Cardiopulmonary exercise testing and radionuclide angiography (to determine right and left ventricular ejection fraction) were prospectively performed in 205 consecutive patients with moderate CHF (140 patients in New York Heart Association [NYHA] class II, 65 in class III). RESULTS: Left ventricular ejection fraction was 29.3%+/-10.1%, RVEF was 37.5%+/-14.6% and peak oxygen consumption (VO2) was 16.2+/-5.4 ml/min/kg (60.2%+/-19% of maximal predicted VO2). After a median follow-up period of 755 days, there were 44 cardiac-related deaths, 3 deaths from noncardiac causes and 15 transplantations of whom 2 were urgent; 1 patient was lost to follow-up. Multivariate analysis showed that three variables-NYHA classification, percent of maximal predicted VO2 and RVEF-were independent predictors of both survival and event-free cardiac survival. Left ventricular ejection fraction and peak VO2 normalized to body weight had no predictive value. The event-free survival rates from cardiovascular mortality and urgent transplantation at 1 year were 80%, 90% and 95% in patients with an RVEF <25%, with a RVEF > or =25% and <35% and with a RVEF > or =35%, respectively. At 2 years, survival rates were 59%, 77% and 93% in the same subgroups, respectively. CONCLUSIONS: In addition to the NYHA classification and to the percent of maximal predicted VO2, RVEF is an independent predictor of survival in patients with moderate CHF.

Plasma levels of atrial natriuretic peptide at peak exercise: a prognostic marker of cardiovascular-related death and heart transplantation in patients with moderate congestive heart failure.

BACKGROUND: Conflicting data have been published concerning exercise performance and hormonal activation. Previous studies have demonstrated the prognostic information of plasma levels of neurohormones at rest in patients with congestive heart failure. No study has examined the prognostic information of plasma levels of hormones at peak exercise. METHODS: Fifty-five consecutive ambulatory patients with stable moderate congestive heart failure (New York Heart Association class II to III) performed a maximal symptom limited cardiopulmonary exercise test with the determination of peak oxygen consumption. Blood samples were drawn at rest and at peak exercise for the determination of plasma levels of atrial natriuretic peptide, aldosterone, and plasma renin activity. RESULTS: Hormonal activation was present at rest, and exercise significantly increased hormonal values. There was no correlation between exercise parameters and hormonal values either at rest or at peak exercise. After a median follow-up period of 724 days, in univariate and multivariate Cox analysis, the most significant independent prognostic marker was the plasma level of atrial natriuretic peptide at peak exercise. Patients with a plasma level of atrial natriuretic peptide > 38 pmol/L had an event rate of 48% compared with an event rate of 14.8% in the other subgroup (p < 0.01). CONCLUSIONS: In patients with stable moderate congestive heart failure, exercise increased hormonal values, but there was no relationship between hormonal activation and exercise performance. Plasma level of atrial natriuretic peptide at peak exercise was the most significant independent marker of cardiovascular-related death and of cardiovascular-related death and heart transplantation.

[Coronary-left ventricular fistula in post-infarction of the myocardium. Apropos of a new case. Review of the literature]. / Fistule coronaro-ventriculaire gauche post-infarctus du myocarde. A propos d'un nouveau cas. Revue de la littérature.

The authors report a new case of acquired corono-left ventricular fistula found in a 46-year-old man four months after a first myocardial infarction treated by fibrinolysis then conventional angioplasty. This is one of the rare cases of post-infarction corono-ventricular fistula, only five of which have been reported in the literature. While their described features seem relatively constant, enabling their distinction from post-angioplasty corono-ventricular fistulas (also rarely described: four cases), certain doubts persist as to their treatment, and above all their mechanism. Monitoring for four years by coronary angiography, which is the special feature of the case reported here, leads us to include this entity within the wider context of post-infarction ventricular remodelling, of which it would then be a very rare complication.

Pericardioscopy in the etiologic diagnosis of pericardial effusion in 141 consecutive patients.

BACKGROUND: Although previous small series have documented the utility of pericardioscopy for accurate etiologic diagnosis of pericardial effusion, this technique remains underused. The aim of our study was to assess the benefits and risks of surgical pericardioscopy in a large prospective series. METHODS AND RESULTS: One hundred forty-one consecutive patients with unexplained pericardial effusion underwent 142 pericardioscopies with a rigid mediastinoscope. For each patient, the etiologic data obtained by pericardioscopy (visualization of pericardium, guided biopsies, subxiphoid window biopsy, and fluid analysis) were compared with the results that would have been obtained with only conventional surgical drainage and biopsy (subxiphoid window biopsy and fluid analysis). After complete workup, a specific cause was found in 69 cases (48.6%); the other 73 cases were considered idiopathic effusions (51.4%). Procedural and in-hospital mortality was 8 of 141 patients (5.6%). No death was directly attributable to pericardioscopy. During long-term follow-up (median duration, 24 months; range, 6 to 96), a previously unrecognized cause was discovered in 6 patients (4%). By comparing the areas under the receiver-operating characteristic curves, the diagnostic advantage of pericardioscopy was significant for the whole series (pericardioscopy, 0.98 +/- 0.011; conventional surgical drainage, 0.89 +/- 0.029; P < .001). The increase in sensitivity was more marked for some types such as neoplastic (21%), radiation-induced (100%), or purulent (83%) effusions. CONCLUSIONS: Our data demonstrate that pericardioscopy increases the diagnostic sensitivity of surgical pericardial drainage and biopsy without specific risk.