Levosimendan in the treatment of cardiogenic shock

Patients with cardiogenic shock (CS) are currently treated with acute coronary revascularization, mechanical support (i.e., IABP), and in addition with vasopressor and inotropic support. Among medical treatment dobutamine and norepinephrine are drugs of first choice. Nowadays, intravenous levosimendan, a new calcium sensitizer and K-ATP channel opener, has emerged as an alternative option of pharmacologic inotropic support in patients with cardiogenic shock. Recent reports on levosimendan's use in cardiogenic shock demonstrated more favorable effects when compared with conventional inotropic agents. Clearly, levosimendan is able to archieve profound increase of cardiac index and cardiac power index in combination with reduced systemic and pulmonary resistance reduction compared to conventional therapy. Further, levosimendan is able to improve hemodynamic parameters more rapidly compared to intraaortic ballon counter pulsation. Similar, in patients with low cardiac output syndrome upon cardiovascular surgery, levosimendan is able to improve cardiac performance when administered prior or after cardiac surgery. In the light of cardiogenic shock, the myocardial protective effects of levosimendan might be important to reduce reperfusion injury and myocardial stunning following ischemia and reperfusion. This review summarizes the evidence from current scientific literature including our recent trials regarding the mechanism of action, efficiency and the use of levosimendan in CS patients.

Anti-inflammatory actions of aprotinin provide dose-dependent cardioprotection from reperfusion injury

BACKGROUND AND PURPOSE

Myocardial injury following ischaemia and reperfusion has been attributed to activation and transmigration of polymorphonuclear leukocytes (PMNs) with release of mediators including oxygen-derived radicals and proteases causing damage.

EXPERIMENTAL APPROACH

We studied the serine protease inhibitor aprotinin in an in vivo rabbit model of 1 h of myocardial ischaemia followed by 3 h of reperfusion (MI+R). Aprotinin (10,000 Ukg(-1)) or its vehicle were injected 5 min prior to the start of reperfusion.

KEY RESULTS

Myocardial injury was significantly reduced with aprotinin treatment as indicated by a reduced necrotic area (11+/-2.7% necrosis as percentage of area at risk after aprotinin; 24+/-3.1% after vehicle; P<0.05) and plasma creatine kinase activity (12.2+/-1.5 and 17.3+/-2.3 IU g(-1) protein in aprotinin and vehicle groups, respectively, P<0.05). PMN infiltration (assessed by myeloperoxidase activity) was significantly decreased in aprotinin-treated animals compared to vehicle (P<0.01). Histological analysis also revealed a substantial increase in PMN infiltration following MI+R and this was significantly reduced by aprotinin therapy (44+/-15 vs 102+/-2 PMN mm2 in aprotinin vs vehicle-treated animals, P<0.05). In parallel in vitro experiments, aprotinin inhibited neutrophil-endothelium interaction by reducing PMN adhesion on isolated, activated aortic endothelium. Finally, immunohistochemical analysis illustrated aprotinin significantly reduced myocardial apoptosis following MI+R.

CONCLUSIONS AND IMPLICATIONS

Inhibition of serine proteases by aprotinin inhibits an inflammatory cascade initiated by MI+R. The cardioprotective effect appears to be at least partly due to reduced PMN adhesion and infiltration with subsequently reduced myocardial necrosis and apoptosis.

[Interstitial pulmonary siderofibrosis: requirements for acceptance as new occupational disease]

BACKGROUND

Pulmonary siderosis is a well established disorder in welders. Internationally more than 150 cases of interstitial pulmonary siderofibrosis are associated with long-standing and heavy exposure to welding fumes at poorly ventilated working places.

PATIENTS

Characteristic job histories, lung function analyses and histological examinations as well as elemental microanalysis by energy dispersive X-ray analysis (EDX) are demonstrated from 3 welders with pulmonary siderofibrosis.

RESULTS

Histological examinations show a patchy interstitial fibrosis with accumulations of particulate material typical for welding fumes. EDX disclose an increase of iron-load in activated macrophages as well as in lung tissue and a close topographical relationship of welding fume particles and interstitial fibrotic reactions. Lung function analysis showed predominantly loss of pulmonary performance during spiroergometry.

CONCLUSIONS

Regarding the actual knowledge about the pathomechanisms of ultrafine particles on lung tissue, the evidence from animal experiments, the histological and electron microscopical results, our own clinical examinations of welders and some epidemiological evidence, we assume a causal relationship of interstitial pulmonary siderofibrosis in welders with long-standing exposure to high concentrations of welding fumes under poor working conditions.

Interstitial pulmonary fibrosis after severe exposure to welding fumes

BACKGROUND

Interstitial pulmonary fibrosis (IPF) is reported after long term, severe exposure to welding fumes in poorly ventilated workplaces.

METHODS

Fifteen welders with IPF were examined--13 in our outpatient clinic--from 1990 to 1997. Occupational histories and examinations, lung function analyses, symptoms and clinical findings, histological analyses in 13 patients partly including SEM/EDX-analyses, chest X-rays, chest computed tomographies were conducted.

RESULTS

Duration of work as welders was 28 years and the cumulative dose of welding fumes 221 mg/m(3) x years (median). Lung function studies found pattern of restriction or combined restriction-obstruction, lower diffusion capacity, and reduced blood oxygen tension at exercise. Histologically, patchy interstitial fibrosis was noted. Accumulations of particulate matter typically for welding fume were detected. EDX showed increase of iron load and close topographical relationship to welding fume particles embedded in areas of scattered fibrosis.

CONCLUSION

While epidemiological data are limited, it is reasonable to conclude that a causal relationship exists between IPF in welders with long term exposure to high concentrations of welding fumes.