Muscular counterpulsation: preliminary results of a non-invasive alternative to intra-aortic balloon pump

Objectives: IABP is the most widely used form of temporary cardiac assist and its benefits are well established. We designed an animal study to evaluate a device based on muscular counterpulsation (MCP) that should reproduce the same hemodynamic effects as IABP in a completely non-invasive way. Methods: Six calves, 60±4 kg, divided into 2 groups, in general anaesthesia, equipped with EKG, Swan-Ganz, pressure probe in the femoral artery and flow probe in the left carotid artery, received either IABP through right femoral artery, or muscle counterpulsation (MCP). MCP consists of electrically induced skeletal muscle contraction during early diastole, triggered by EKG and microprocessor controlled by a portable device. For each animal the following parameters were also considered: mean aortic pressure (mAoP), CO, CI, left ventricular stroke work index (LVSWI), systemic vascular resistance (SVR) and mean femoral artery flow (Faf). We did 3 sets of measurements: baseline (BL), after 20 (M20) and 40 (M40) min of cardiac assistance. These measurements have been repeated after 40 min of rest for 3 times. Results are expressed as mean±SD. Results: Baseline values: mAoP, 76.51±12 mmHg; mCVP, 11.5±3 mmHg; CO, 5±1 l/min per m2; LVSWI, 0.77±0.2KJ/m2; SVR, 1040±15dyns/cm−5; Faf, 75.5±10 ml/min. IABP group: mAoP, 81.1±6 mmHg; mCVP, 1±0.1 mmHg; CO, 4.5±0.7 l/min per m2; LVSWI, 0.69±0.2KJ/m2; SVR, 1424±8dyns/cm−5; Faf, 64.3±3 ml/min. MCP group: mAoP, 60.1±7 mmHg; mCVP, 23.6±2 mmHg; CO, 4.8±0.4 l/min per m2; LVSWI, 0.69±0.2KJ/m2; SVR, 608±25dyns/cm−5; Faf, 92.3±12 ml/min. Conclusions: MCP and IABP had the same effects on CO and LVSWI. Moreover, MCP reduced SVR and increased the peripheral circulation without requiring any vascular access nor anticoagulation therap

Insuffisance cardiaque résistant au traitement médicamenteux : greffe et alternatives

La greffe cardiaque reste actuellement la méthode de référence pour le traitement des patients en Insuffisance cardiaque terminale avec de meilleurs résultats globaux que le traitement médicamenteux seul, tant au niveau qualité de vie quotidienne que survie à moyen terme. Cette activité va cependant rester stable dans le proche futur vu le manque généralisé de donneurs. Ces patients seront dès lors pris en charge par une association de nouveaux traitements médicamenteux et interventionnels, des interventions chirurgicales combinées, de la thérapie génique et une technologie d'assistance ventriculaire à visée définitive, approches multidisciplinaires dont on espère un résultat comparable à la greffe cardiaque, à savoir 50% de survie après quinze ans

Myocardial damage induced by uncontrolled reoxygenation

To evaluate myocardial impairment induced by uncontrolled reoxygenation, the effects of hypoxia-reoxygenation were compared with ischemia-reperfusion in isolated rat hearts. After stabilization, 2 groups (n = 8) of Langendorff-perfused rat hearts were exposed to 40 minutes of ischemia (10% of baseline flow) or hypoxia (10% of baseline oxygen content) followed by a sudden return to baseline conditions (reperfusion or reoxygenation). The O2 content was identical for the two groups during baseline conditions, O2 shortage, and O2 readmission. Metabolic (lactate production) and functional parameters (heart rate, peak systolic pressure, left ventricular developed pressure, maximal contraction and relaxation rates, end-diastolic pressure, coronary perfusion pressure) were recorded at the end of stabilization, after O2 deficiency, and after 2 minutes of reoxygenation. Systolic function was significantly depressed after ischemia (p < 0.0001) but completely recovered to baseline values after 2 minutes of reperfusion. In contrast, systolic function was less severely depressed after hypoxia but failed to return to baseline after 2 minutes of reoxygenation. Diastolic function, unchanged during ischemia-reperfusion, remained significantly impaired during hypoxia-reoxygenation