Effectiveness of aldosterone antagonists for preventing atrial fibrillation after cardiac surgery in patients with systolic heart failure: a retrospective study.

Postoperative atrial fibrillation (POAF) is the most common arrhythmia after cardiac surgery. There exist consistent experimental and clinical data suggesting that aldosterone antagonists (AAs) may exert beneficial effects regarding electrical and structural remodeling in failing myocardium. Recently, eplerenone (EPL) has been found to reduce the incidence of nonsurgical AF when added to guideline-recommended therapy in patients with systolic heart failure. Based on these findings, we primarily aimed to evaluate by retrospective analysis the impact of the two AAs, EPL and spironolactone (SPL), given at standard therapeutic doses in preventing new-onset POAF in patients the majority of which had a preoperative ejection fraction (EF) below 40%. A total of 332 patients (298 men/34 women, mean age 64.3 ± 9 years) without history of AF were included in this analysis; 132 of these patients received long-term EPL or SPL in addition to beta-blockade/statins therapy and 200 patients received neither EPL nor SPL. All patients underwent on-pump coronary artery bypass graft (80%) and/or valvular surgery (20%). In the nonAA group (EF = 35.8 ± 6%) 90/200 patients (45%) had POAF, while in the AA group (EF = 36.2 ± 5%) only 40/132 patients (30.3%) developed POAF (P < 0.01, χ (2) test). Multivariate logistic regression analysis revealed that only AAs and left atrial diameter significantly affected the development of POAF even when adjusted for other clinical variables (P < 0.05). In conclusion, AAs significantly reduced the incidence of POAF when added to standard heart failure therapy in patients undergoing on-pump cardiac surgery.

Monitoring serum chondroitin sulfate levels in patients submitted to coronary artery bypass surgery.

Glycosaminoglycans (GAGs) are functionally important molecules of the arterial wall and play a crucial role in atherogenesis. Chondroitin sulfate/dermatan sulfate proteoglycans (CS/DSPGs) participate in several biological events through their GAG chains, and are also involved in the development of atherosclerosis. The aim of this study was to compare the pre- and post-operative levels of CS in serum of patients after coronary artery bypass graft surgery using a highly sensitive reversed-polarity capillary electrophoresis method and to investigate the correlation of CS with common biochemical lipid markers. It was found that CS values were significantly higher for all patients post-operatively and, furthermore, CS levels were statistically correlated to apolipoprotein A and B levels. Notably, the pre-operational lipid profile of the patient may be indicative of the values of 4-sulfated CS post-operationally. Furthermore, the obtained results highlight the clinical significance of CS levels in serum, since they may provide complementary information for the latent inflammatory state of the patient.

Effect of histamine on the electrophysiology of the human parietal pleura.

INTRODUCTION: Histamine is involved in the pathogenesis of numerous diseases and regulates the permeability of different tissues. The aim of this study is to investigate the effects of histamine on the electrophysiology of human parietal pleura and the underlying mechanisms involved. MATERIALS AND METHODS: Pleural specimens were obtained from patients subjected to thoracic surgery and were mounted in Ussing chambers. Histamine solutions (1µM to 1mM) were applied in native and pretreated specimens with dimetindene maleate, cetirizine, ranitidine, amiloride and ouabain. Trans-mesothelial resistance was determined (R(TM)). RESULTS: Histamine induced a rapid R(TM) increase on the mesothelial (p = 0.008) and a decrease on the interstitial surface (p = 0.029). This effect was dose-dependent and was totally abolished by dimetindene maleate, cetirizine and amiloride and partially by ranitidine and ouabain. CONCLUSIONS: Histamine induces acute electrochemical changes in human pleura mainly via interaction with the H(1) and partially with the H(2) histamine receptors. It also interferes with trans-cellular permeability and therefore may participate in pleural fluid recycling.

Glycosaminoglycans as key molecules in atherosclerosis: the role of versican and hyaluronan.

Cardiovascular disease is the largest cause of death in Western societies and it primarily results from atherosclerosis of large and medium-sized vessels. Atherosclerosis leads to myocardial infarction, when it occurs in the coronary arteries, or stroke, when it occurs in the cerebral arteries. Pathological processes involved in macrovascular disease include the accumulation of lipids which are retained by extracellular matrix (ECM) molecules, especially by the chondroitin sulfate/dermatan sulfate (CS/DS) proteoglycans (CS/DSPGs), such as versican, biglycan and decorin. The sulfation pattern of CS is a key player in protein interactions causing atherosclerosis. Several studies have shown that lipoproteins bind CSPGs via their glycosaminoglycan chains. Galactosaminoglycans, such as CS and DS, bind low density lipoproteins (LDL), affecting the role of these molecules in the arterial wall. In this article, the role of CS and versican in atherosclerosis and hyaluronan in atherogenesis as well as the up to date known mechanisms that provoke this pathological condition are presented and discussed.

Surgical complications of hyperglycaemia.

We review the mechanisms leading to hyperglycaemic damage and draw functional extrapolations aiming to an improved management of surgical complications, which are common among diabetic patients.

The impact of fluid restriction policy in reducing the use of red blood cells in cardiac surgery.

Hemodilution contributes significantly to transfusion requirements in patients undergoing CABG under CPB. We hypothesised that restriction of parenteral fluids in comparison to a liberal fluid administration policy leads to less use of packed red cells in CABG operations supported by cell salvage. After consent and approval, 130 patients operated under equal conditions were assigned prospectively and randomly either for a restrictive protocol for intravenous fluid administration (group A, 65 pts) or not (group B, 65 pts). Transfusion guidelines were common for the two groups. The volumes of intravenous fluids, priming, "extra" volume on pump and cardioplegic solution and the volume of urine were recorded. Net erythrocyte volume loss was calculated. The number of the transfused PRC was analyzed as a continuous variable. "Transfusion" was analyzed as a categorical characteristic. Significant difference existed between groups for the fluids administered intravenously until the initiation of CPB and for fluid balance after CPB. Intraoperatively transfused units were significantly lower in A (0.32 +/- 0.77 vs 1.26 +/- 1.05 u/per pt; p<0.0001). Transfused patients were also significantly lower in A (11/65 vs 44/65; p<0.0001). In both groups, the values of hematocrit were statistically decreased. The greatest difference compared to the preoperative values was observed after CPB (from 40.8 +/- 4.2 to 21.9 +/- 3.6 for A, and from 40.2 +/- 3.7 to 19.7 +/- 3.3 for B ; p<0.0001 for both). For these lowest values, significant difference existed between groups (p<0,001) while the difference in the hematocrit values to the end of operation was insignificant. Transfusion in ICU showed no significant difference among groups. Hours of mechanical ventilation in ICU were ranging from 5 to 29 (mean = 10.0, median = 9) for A and from 5 to 42 (mean = 14.8, median = 10) for B. Length of stay in ICU in nights for group A was ranging from 1 to 10 (mean = 2.7, median = 2) and for group B was ranging from 1 to 6 (mean = 3.5, median = 2). In conclusion, reduction of transfusions in CABG operations is feasible when a restrictive protocol for intravenous fluids is applied.

Hydralazine is a powerful inhibitor of peroxynitrite formation as a possible explanation for its beneficial effects on prognosis in patients with congestive heart failure.

The hemodynamic and anti-ischemic effects of nitroglycerin (GTN) are rapidly blunted as a result of the development of nitrate tolerance. Hydralazine has been shown to prevent tolerance in experimental and clinical studies, all of which may be at least in part secondary to antioxidant properties of this compound. The antioxidant effects of hydralazine were tested in cell free systems, cultured smooth muscle cells, isolated mitochondria, and isolated vessels. Inhibitory effects on the formation of superoxide and/or peroxynitrite formation were tested using lucigenin and L-012 enhanced chemiluminescence as well as DHE-fluorescence. The peroxynitrite scavenging properties were also assessed by inhibition of nitration of phenol. Prevention of impairment of NO downstream signaling and GTN bioactivation was determined by measurement of P-VASP (surrogate parameter for the activity of the cGMP-dependent kinase-I, cGK-I) and mitochondrial aldehyde dehydrogenase (ALDH-2) activity. Hydralazine dose-dependently decreased the chemiluminescence signal induced by peroxynitrite from SIN-1 and by superoxide from HX/XO in a cell free system, by superoxide in smooth muscle cells and mitochondria acutely challenged with GTN. Moreover, hydralazine inhibited the peroxynitrite-mediated nitration of phenols as well as proteins in smooth muscle cells in a dose-dependent fashion. Finally, hydralazine normalized impaired cGK-I activity as well as impaired vascular ALDH-2 activity. Our results indicate that hydralazine is a highly potent radical scavenger. Thus, the combination with isosorbide dinitrate (ISDN) will favorably influence the nitroso-redox balance in the cardiovascular system in patients with congestive heart failure and may explain at least in part the improvement of prognosis in patients with chronic congestive heart failure.

[Results of immediate and delayed bypass operation in PTCA emergencies]. / Ergebnisse der sofortigen und der verzögerten Bypass-Operation beim PTCA-Notfall.

UNLABELLED: The therapeutic strategy for irreversible coronary occlusion as a complication of PTCA is influenced by the rate of myocardial infarctions and mortality after emergency bypass surgery. If immediate bypass operation cannot prevent myocardial infarction, medication will be the treatment of choice. Since the duration of ischemia is of critical importance for the preservation of myocardium, we analyzed our results with respect to the time interval from the onset of ischemia to surgery. From 12/84 to 12/93 there were 49 emergency operations for 4,478 PTCAs. In 38 patients acute closure occurred in the cath lab; because of very strict standby arrangements these patients could be brought to the operating rooms without delay (group A). In 11 patients acute closure occurred during the following 24 hours in the intermediate care unit (group B); attempts of catheter recanalisation and/or preparation for surgery accounted for an additional time delay until surgery of 79 minutes. RESULTS: In the 38 patients of group A there were only one small transmural (CKmax 533/U/l) and four non-Q wave (CK-max 322 U/l) myocardial infarctions. Of the 11 patients in group B only two did not suffer any loss of myocardium. In seven cases there were transmural (CKmax 1,296 U/l) and in two cases non-Q wave (CKmax 721 U/l) myocardial infarctions. Two patients of group B died on the second and third postoperative day. Thus the results of emergency bypass operations were excellent if surgery could be performed immediately after failure of catheter interventions (all survived, no transmural M.I. in 97%).(ABSTRACT TRUNCATED AT 250 WORDS)

A new sternal retraction device for the dissection of the internal mammary artery.

For the dissection of the internal mammary artery (IMA), we use a new sternal retraction technique. The retractor is an angled stainless steel device with a slotted face and two sternal arresting hooks. The method is simple and the device acts as a unit with a standard sternal spreader. The time period between mounting and the exposure of the IMA is only a few seconds. The entire procedure takes place in the sterile operative field. By utilizing this method, we dissected nearly 300 IMAs without any complications or serious sternal injuries.

[Acute pulmonary embolism--are vena cava interruption procedures and extracorporeal circulation always necessary?]. / Die akute Lungenarterienembolie--sind Cavasperroperationen und extrakorporale Zirkulation immer notwendig?

Between 1983 und 1991, emergency pulmonary embolectomy with the aid of extracorporeal circulation was performed in 13 patients. Ten patients were in class IV according to Greenfield, seven came into the operating theater with external cardiac massage. The 30-day mortality was 46%. In the same period, 15 venous interruption procedures were performed (three Adams de Weese Clip, ten Greenfield-Filter, and two femoral vein ligations). Eight times the venous interruption procedure was done prophylactically. The acute pulmonary embolism of class III and IV according to Greenfield is an indication for lytic therapy. We operate only if there is a contraindication to lytic therapy or if there is deterioration of the clinical state.

[Accidental drowning with extreme hypothermia--rewarming with extracorporeal circulation]. / Unfall durch Ertrinken mit extremer Unterkühlung--Wiedererwärmung mittels extracorporaler Zirkulation.

A 3 1/2 year old boy had fallen into a fishpond. After about one hour the boy was brought to our hospital. He was cyanotic and bloated, the rectal temperature was 18.4 degrees C. There was no heart beat, the pupils were wide without reaction to light. Via a sternotomy the heart lung machine was connected and core rewarming was achieved. After 7 days of artificial respiration the boy could be extubated, after 16 days the boy left our hospital without neurological consequences.

[Coronary spasm immediately following coronary revascularization]. / Koronarspasmus unmittelbar nach Koronarrevaskularisation.

Of 2,600 coronary operations performed from August 1983, to December 1988, two ischemic reactions of the inferior wall immediately after operation were observed. In both patients the right coronary artery was either dissected or revascularized intraoperatively. Under the diagnosis of postoperative spasm both patients had reangiography three hours after surgery. Right coronary artery spasm was demonstrated in both patients. After intracoronary injection of calcium channelblockers the spasm resolved completely. Patient 1 demonstrated a small inferior infarction during control angiography, patient 2 remained free of a myocardial infarction. The possible causes of coronary spasm during or after surgery are discussed. The diagnosis and an approach to therapy are outlined.

[Use of the mammary artery in coronary revascularization]. / Verwendung der Arteria mammaria zur Coronarrevascularisation.

From August 1983 through December 1985 1088 patients underwent coronary surgery. 406 (37%) received a single or bilateral internal mammary artery (IMA) graft with single or sequential anastomoses. The youngest patient was 6 years old, the oldest 75, with a mean age of 55.7 years. A total of 672 IMA anastomoses was constructed. In addition 348 patients received 610 saphenous vein grafts. 83% of the IMA were anastomosed to the LAD and its branches, 12% to the circumflex and 5% to the right coronary artery. 4 patients (0.98%) died postoperatively, 402 survived and are free of angina. In our experience the IMA can be used routinely with low operative risk and good results.